Posts

Intraoperative Graft Contamination – What Options Do We Have?

Parag Sancheti, Sachin R Jain, Ashok Shyam

Volume 1 | Issue 1 | April – Jun 2016 | Page 35-37


Author: Parag Sancheti [1], Sachin R Jain [1], Ashok Shyam [1],[2]

[1] Sancheti Institute for Orthopaedics & Rehabilitation, Pune, India
[2] Indian Orthopaedic Research Group, Thane, India

Address of Correspondence

Dr Parag Sancheti
Sancheti Institute for Orthopaedics & Rehabilitation, Pune, India
Email: parag@sanchetihospital.com


Abstract

Background: Accidental graft contamination is not uncommon in a high volume centers practicing ligament reconstruction surgeries. There are several techniques of disinfecting the graft to prevent septic arthritis postoperatively. Aim of this review is to identify the different options of appropriate disinfectant and also the time interval for immersing the graft in the disinfectant solution for contaminated ACL graft.
Material and methods: MEDLINE, Pubmed and extensive searches of major arthroscopy journals identified several studies regarding graft contamination and its disinfection protocol which was used in this study.
Conclusion: 4% chlorhexidine or 10 % povidone iodine seem to be most effective in disinfecting contaminated graft after immersion for 3 min and 15 min respectively. All sutures should be removed prior to disinfection and proper antibiotic cover and follow up should be done to prevent any residual infection.
Keywords: Anterior cruciate ligament reconstruction, graft contamination, antiseptics


Introduction

Anterior Cruciate Ligament (ACL) reconstruction is the most common ligament reconstruction surgery done in the world(1). There is always a possibility of inadvertent graft contamination by dropping it accidentally on floor(2). 25% of fellows in sports medicine report at least one such event(3). Various treatment modalities exist to prevent postoperative infection due to contaminated graft such as cleansing alone with normal saline, immersion in 4 % chlorhexidine and bacitracin solution, 10% povidone – iodine solution, sodium hypochlorite solution or antibiotic solution wash (2,3,4,5). Other option is to discard the graft and harvest another graft or use an allograft, but this causes donor site morbidity or increased cost associated with use of allograft(3). Floor cultures can be simultaneously obtained to find out the organism grown during contamination.

Methods

MEDLINE, Pubmed and extensive searches of major arthroscopy journals identified several studies regarding graft contamination and its disinfection protocol which was used in this study. Aim of this review was to find out the epidemiology of graft contamination, different agents used for decontaminating the graft and its efficacy, organism grown in floor or contaminated graft culture, cleaning protocol for hamstring graft and for bone patellar bone tendon graft, preventing measures for graft contamination and finally treatment with antibiotic protocol postoperatively.

Discussion

Around 25% surgeons have reported to have a contaminated graft at least once with 35% of these surgeons performing at least 100 ACL surgeries annually (1). Sterilization by autoclaving destroys the material properties of collagenous tissue, so other sources of nondestructive disinfection must be considered (9).

Barbier et al(2) compared 4 groups after dropping graft on the floor with cultures taken after immersion in antiseptic solution for 15 min – 4 % chlorhexidine gluconate solution (group 1),  10% povidone–iodine solution (group 2), sodium hypochlorite solution (group 3) and (group 0) was cultured without being exposed to any solution. They found that floor swab cultures were positive in 96% of cases and rate of contamination was 40% in group 0, 8% in group 1, 4% in group 2, and 16% in group 3. There was a significant difference between groups 1 and 2 and group 0 (p < 0.05) but not between groups 3 and 0. They concluded both 4% chlorhexidine as well as povidone iodine solutions are effective in treatment of contaminated graft. Sodium hypochlorite is not so effective with this respect. Molina et al.(8) found that 58% of the dropped grafts had positive cultures and also, 4 % chlorhexidine and double antibiotic solution (neomycin and polymyxin B) successfully decontaminated dropped native ACLs at a rate of 98 and 94 %, respectively. The time duration used by different surgeon varies for different surgeons which ranges from 90 seconds to 30 minutes(1). The most common antiseptic solution chosen by the high volume surgeons was chlorhexidine(1). However, when povidone– iodine solution was used, 24 % of the ACL graft had resulted in positive cultures. Graft can be washed for a period 3 min to reduce undue delay of the surgery(3). Their limitation was that the graft was kept in the sterilizing agent for 90sec and then sent for culture. Pasque et al(10) suggested getting the graft off of the floor immediately, removing any suture material in the graft, cleansing the graft for 15 to 30 minutes each in chlorhexidine and triple antibiotic solution, followed by a normal saline rinse is associated with very less chance of infection. Casalonga et al. (11) followed the outcome of four patients in whom the B-T-B graft dropped onto the floor was re-implanted after decontamination with topic antibiotics. The grafts were soaked in rifamycin and then gentamycin for 10 min each along with postoperative antibiotics for 15 days. There were no complications or postoperative infections, and all patients were able to return to previous sport level. Cooper et al (12) after soaking contaminated grafts in antibiotic solution for 15 min suggested it may reduce the incidence of positive cultures but it may still result in a 30% incidence of nonsterile grafts. Floor cultures most commonly grow coagulase-negative Staphylococcus, bacillus species and diphtheroids(13, 3). The limitation of this study that it was done in cadavers. Plante et al (3) suggested that immediate graft retrieval (<5 sec) did not affect the rate of contamination when compared to fifteen-second exposure (33 vs. 23 %). Sobel et al(14) suggested that structural properties of human patellar tendon allografts are not significantly affected by soaking in 4% chlorhexidine gluconate for 30 minutes. Stanwood et al(1) stated that 71% of surgeons who experienced graft contamination cleansed the graft, and 75% contaminated grafts were cleansed and the ACL reconstruction proceeded as planned. In 18% an alternative autologous graft of contralateral patellar tendon or ipsilateral hamstrings was used to replace the contaminated graft and in 7% of cases, an allograft was used.

In general, the rate of contamination of graft if dropped on floor is between 63 to 96 % and the contaminant grown in culture is staphylococcus(12,8,10, 2). Also, the time interval of dropping the graft and its retrieval doesn’t influence the culture as the different studies have compared the different time interval i.e. 15 sec,  3 min which found similar growth(2). This suggests a definite need of treatment of graft after contamination irrespective of the time duration. Chlorhexidine and povidone iodine solutions both are broad spectrum antiseptics and chlorhexidine is activated in less than 1 min and 10% povidone-iodine takes a longer time to activate with increased activity after 5 min(2). This suggested the need of different immersion time required to disinfect the graft in different solution, in 4 % chlorhexidine solution 3 min may be adequate(8) whereas it may require upto 15min  immersion in 10% povidone-iodine solution(2). Soaking of grafts in antibiotic solutions might increase the risk of multiresistant organism being selected(2) also there is 30% risk of getting non sterile graft(12). If a sutured hamstring graft is contaminated then all the sutures are to be removed before immersion in a disinfectant solution(2).

Jones et al(15) studied the mechanical properties patellar tendon allograft subjected to chemical sterilization(BioCleanse) and found that preimplantation mechanical properties of BPTB allografts treated with BioCleanse are not significantly different from those of untreated controls.

Other than dropping of graft on floor, graft contamination during surgery may occur at various steps of surgery before implantation. Hantes et al (6) studied various sources of contamination of hamstring and patellar tendon autograft. Three tissue samples were obtained for culture from each graft at different time-intervals during graft preparation process, during graft preparation completion and during graft implantation. In addition, the erythrocyte sedimentation rate and the C-reactive protein level were evaluated preoperatively and on the third, seventh, and twentieth postoperative days. Authors concluded that a high rate (12%) of autograft contamination can be expected during autograft preparation for anterior cruciate ligament reconstruction. The contamination rate is almost equal for both bone-patellar tendon-bone and hamstring tendon autografts which was confirmed with normal ESR and CRP reports. However, there was no evidence of postoperative infection with intraoperative contamination results in their series. They further suggested that no excessive antibiotic is required for positive cultures and no evidence of clinical signs of infection. Postimplantation of the contaminated graft after disinfection, it is advised to treat the patient with IV antibiotics and/or oral antibiotics for 1 or 2 weeks. Also, a close watch to be kept until 6 weeks of surgery ifany signs of infection develops(10).

There is a very high chance of contamination of graft when a new staff is given the responsibility of holding graft or surgeon goes to a new setup(10). To prevent this, surgeon should personally get the graft from the time of harvest till getting it on the preparation table. Similarly, new staff or resident who is preparing the graft should be adequately trained and strictly monitored to prevent dropping of graft. Finally all the OR personnel should realize the importance of surgery and be careful at all times especially while transfer of graft from preparation table to implantation site and vice versa.


Conclusion

4% Chlorhexidine with or without bacitracin is the best solution for disinfection of contaminated graft. Graft has to be minimum kept for 3 min immersed in the solution for proper disinfection. If 10% povidone-iodine is to be used graft has to be immersed at least 15 minutes. Earlier the retrieval of graft, better the disinfection as shown comparison between less than 5 second retrieval and 15 sec graft retrieval from floor. All suture material must be removed while disinfecting the graft. Post implantation, antibiotics have to be given for a period of 1 or 2 weeks and have to be followed for at least 6 weeks


References

  1. Stanwood W, Levine WN, Ahmad CS. A Survey of Sports Medicine Specialists Investigating the Ligament Grafts. 2005;21(11):1348–53.
  1. Barbier O, Danis J, Versier G, Ollat D. The Knee When the tendon autograft is dropped accidently on the fl oor : A study about bacterial contamination and antiseptic ef fi cacy. Knee [Internet]. Elsevier B.V.; 2016;22(5):380–3. Available from: http://dx.doi.org/10.1016/j.knee.2014.07.027
  1. Plante MJ, Li X, Brown MA, Busconi D, Deangelis NA. Evaluation of sterilization methods following contamination of hamstring autograft during anterior cruciate ligament reconstruction. 2013;21(3):696–701.
  1. McAllister DR, Parker RD, Cooper AE, Recht MP AJ. Outcomes of post-operative septic arthritis after anterior cruciate ligament reconstruction. Am J Sport Med. 1999;27:562–70.
  1. Schollin-Borg M M elsson, Micha¨ elsson K RH. Presentation, outcome, and cause of septic arthritis after anterior cruciate ligament reconstruction: a case control study. Arthroscopy. 2003;19:941–7.
  1. Me H, Gk B, Se V, Giotikas D, Petinaki E, Kn M. Autograft Contamination During Preparation for. 2008;760–4.
  1. Stanford R, Solomon M, Levick M, Kohan L, Bell S. Sterilization of Contaminated Bone-Tendon Autografts Using 10% Povidone-Iodine Solution. Orthopedics. 1999;22:601–4.
  1. Molina ME, Nonweiller DE, Evans JA, Delee JC. Contaminated anterior cruciate ligament grafts: the efficacy of 3 sterilization agents. Arthroscopy. 2000 May-Jun;16(4):373-8.
  1. Davis KW, Stauderman WE, Mayfield J WJ. Gamma radiation dose setting and auditing strategies for sterilization of medical devices. In: Gaughran ERL, Morri-of medical products. Montreal. Steriliz Multiscience Publ Ltd. 1981; Vol 2:34-102
  1. Pasque C, Geib T. Intraoperative Anterior Cruciate Ligament Graft Contamination. 2016;23(3):329–31.
  1. Casalonga D, Ait Si Selmi T RA et al. Peroperative accidental contamination of bone-tendon-bone graft for the reconstruction of the anterior cruciate ligament. Report of 4 cases. Rev Chir Orthop Reparatrice Appar Mot. 1999;85(7):740–3.
  1. Cooper DE, Arnoczky SP, Warren RF. Contaminated Patellar Tendon Grafts : Incidence of Positive Cultures and Efficacy of an Antibiotic Solution Soak-An In Vitro Study. 1991;272–4.
  1. Richard D. Parker, Evan J. Bachner, Michael J. Dul, Dirk Treleven, Matthew E. Levy and PP. The Scientific Basis for the Management of Contam- inated Bone-Tendon Grafts: The Serial Dilution/ Mechanical Agitation Technique. Arthroscopy. 1993;9(3):354.
  1. Sobel AD, Hohman D, Jones J, Bisson LJ. Structural Properties of Human Patellar Tendon Allografts. YJARS [Internet]. Elsevier Inc.; 2016;28(12):1862–6.
  1. Jones DB, Huddleston PM, Zobitz ME, Stuart MJ. Mechanical Properties of Patellar Tendon Allografts Subjected. 2007;23(4):400–4.

How to Cite this article:. Sancheti P, Jain SR, Shyam AK. Intraoperative Graft Contamination – What Options Do We Have? Asian Journal of Arthroscopy  Apr- June 2016;1(1):35-37 .

Dr. Parag Sancheti

Dr. Parag Sancheti

Dr. Sachin Jain

Dr. Sachin Jain

Dr. Ashok Shyam

Dr. Ashok Shyam

 


(Abstract)      (Full Text HTML)      (Download PDF)


Future Trends In Grafts Used In ACL Reconstruction

S R Sundararajan, Balaji Sambandam, S Rajasekaran

Volume 1 | Issue 1 | April – Jun 2016 | Page 29-34|


Author: S R Sundararajan [1], Balaji Sambandam [1], S Rajasekaran [1]

[1] Ganga Hospital, 313, MTP road, Coimbatore , Tamilnadu, India Pin code – 641043

Address of Correspondence

Dr Sundararajan S R
Ganga hospital,313, MTP road, Coimbatore , Tamilnadu, India, Pin code – 641043
Email id – sundarbone70@hotmail.com


Abstract

Anterior cruciate ligament injury is the commonest sports injury in day to day orthopaedic practice and arthroscopic reconstruction of anterior cruciate ligament is the standard of care. This gold standard procedure has evolved continuously since the time of its inception in terms of technique, implant used for fixation and most importantly the graft used. Each period of time was dominated and fascinated by a particular graft option. Though numerous came into the picture only few stood the test of time. Search for the perfect graft for ACL reconstruction still continues. Ideally it should have adequate biomechanical strength, should be easily available and doesn’t cause any harm during harvest or implantation. Today we have the option of autografts, allografts and even synthetic grafts. In the future tissue engineering and gene therapy might play a major role in graft production.
Keywords: Anterior cruciate ligament reconstruction, allograft, synthetic graft


Introduction

History of using tendon grafts for ACL reconstruction started in the early sixties. Kenneth Jones(1) was one of the early surgeons who started using tendon for ACL reconstruction. From then on grafts for ACL reconstruction surgery continued to evolve. Every new source of graft had its own advantages and disadvantages. An ideal graft should be one which is easily available, have the properties similar to the native ACL, get incorporated to the bone easily and don’t cause any donor site morbidity. As of now, there is no such graft which can completely reproduce the structural and biological characteristics of native ACL without causing an untoward effect. Today we have the option of autografts, allografts and few synthetic grafts. The failures are not only because of the characteristics of the graft but also due to graft healing in the bone tunnel. The future trend of grafts for ACL reconstruction might not be same as we see today because of on going research like tissue engineering. In this article we reviewed the commonly used grafts at present and the future evolving concepts.

1. Tendon grafts
The usage of tendon grafts as a substitute to ligament is due to the fact that they are anatomically and histologically similar. These connective tissues are made up of bundles of collagenous fibers arranged in parallel, slightly wavy or curved arrays. Twenty percent of their mass is made up of cellular component and the remaining 80% is the extracellular components. Fibrocytes and fibroblast comprise the cellular component. 80% of their mass is water. Collagen fibers make 65 to 80% of the dry mass. Type 1 collagen is the one which is abundant in both with some type 3 collagen. Amount of collagen and the ratio between type 1 and type 3 are the differences between the two. The amount of collagen is more in tendons than the ligaments and the ratio between type 1 and 3 is 99:1 in tendons where as it is 90:10 in case of ligaments. Apart from anatomical and histological similarity the strength and other biomechanical properties should be similar between the tendon and the ligament to be replaced. Noyes et al[2] did a biomechanical testing to test the strength between natural ACL and various grafts after excluding age and disuse related factors. They found that semitendinosus and gracillis had 70 and 49 % of the strength of natural ACL while patellar tendon has 159 to 168 % strength compared with natural ACL.
The bone tendon interface is composed of a tissue called enthesis which is a transitional zone transmitting the stress from bone to tendon and vice versa. Enthesis is of two types(3). The first type is the direct insertion type which is typically seen in ACL, patellar tendon, rotator cuff, Achilles tendon and femoral attachment of MCL. Here there is a gradual transition from tendon to bone. Microscopically the attachment point shows interdigitation of collagen fibers with transition from tendon, unmineralized fibrocartilage, mineralized fibrocartilage and bone. The superficial fibers are inserted into the periosteum and the deep fibers are attached at right angles or tangentially to the bone in the transition zone. The second type is the indirect type observed in tibial attachment of MCL and deltoid insertion in humerus. Here there is no fibrocartlaginous transition and the tendon fibers pass obliquely along the bony surface and inserts at an acute angle into the periosteum. They are connected by Sharpey’s fibers(4,5). The healing between tendon and bone in case of ligament reconstruction surgery is slightly different. Here there forms a vascularised granulation tissue in the junction which gets replaced by Sharpey’s collagen fibers gradually. The attachment gets further strength when bone grows between the interfaces.
Patellar tendon, hamstring tendon and quadriceps tendon are the three most commonly used autografts. Even among them there is no single outstandingly performing graft. Each one has its own advantage and disadvantage. In a meta analysis done by Li et all (6) patellar tendon graft had favorable outcome in terms of KT-1000 arthrometer values, negative rates of Lachman test and pivot shift while hamstring tendon graft was better in avoiding anterior knee pain, kneeling pain and extension loss. There was no difference in postoperative graft failure rate.

Bone Patellar tendon bone grafts.
BPTB grafts since the time of Jones evolved into a gold standard for ACL reconstruction in last few decades. Jones(1) made a medial parapatellar incision one inch distal to the patella extending just distal to the tibial tubercle. Then a femoral tunnel was made. The central third of the patellar tendon was incised along with a bloc of bone from the patella. The tibial attachment was left intact and the bone block is fixed to the femoral tunnel. Because the graft was attached to the natural insertion site in tibia the length was small making the femoral tunnel to be more anterior than anatomical. Franke was the first to describe the free patellar tendon graft as we use it today(7). By the nineties free bone patellar tendon bone graft became the standard graft for ACL reconstruction and was commonly used. Advantages of this graft are the mechanical strength and the bone to bone healing which occurs with this graft. Anterior knee pain is the major limiting factor for BPTB graft with a reported incidence of 4 to 60 percent(8, 9). The reason for anterior knee pain can be injury to the infrapatellar branch of saphenous nerve, the inflammatory response that occurs during healing of the donor site and even the shortening of the tendon which occurs after graft harvest. To prevent these complications there were many attempts to modify the graft harvesting technique. Berg and Liu sutured the peritenon and filled the bone harvesting site[10, 11]. But these modifications were not entirely satisfactory as seen in further studies[12, 13]. In order to reduce the injury to infrapatellar branch of saphenous nerve, newer minimally invasive two incision techniques were devised. Other more important aspect of concern in this graft is regaining the original strength in the donor site. There are many MRI and ultrasound based studies which showed near complete regain of cross-section area after harvest(14-16). But still rupture of patellar tendon does exist. The risk of rupture is high when closing the defect in the middle with undue tension. Also a tight closure can cause necrosis, fibrosis and shortening of the tendon.When excessive patellar bone is harvested or the intraosseous midpatellar and polar vascular channels are damaged patella fracture can occur(17). There are further modifications in the graft harvesting technique to reduce these complications where instead of the middle third medial third was used(18). Proponents of this technique advocate many advantage of this technique over the classic middle third. Graft can be harvested by a single cut, there is no need to approximate the peritenon and the risk of patellar tendon rupture, shortening, patellar fracture and maltracking are reduced. Today patellar tendon grafts are less frequently used when compared to hamstring tendon grafts. But still it is the graft choice when early bone to bone healing is needed; particularly in sports personnel and athletes who need faster recovery. It is also commonly used in revision surgeries and multiligamenous injuries.

Hamstring tendon graft
Hamstring tendon graft is the commonly preferred graft at present because it can be easily harvested, more cosmetic with few donor site complications with same functional outcome when compared to bone patellar bone graft. Though the use of hamstring tendon as graft became popular in recent time its usage started very early. Galeazzi(19) was the first to use them in 1934. He used semitendinosus tendon to reconstruct ACL. The usage was further made popular by many surgeons like Macey, Lindemann, Agustine(20-22). The reason behind the success of this tendon graft is good clinical outcome and lesser donor site morbidities. Hamstring tendon regenerates after harvest but the time it takes to regenerate and the strength of the newly formed tendon is not clear yet. Careful repair of the facial layer is needed so that the space between layer 1 and 2 in the knee provides a tubular compartment for the tendon to regenerate from the tip of the muscle. This is akin to the nerve regeneration within the endoneurium. Injury to infrapatellar branch of saphenous nerve is a commonly reported complication after the harvest of hamstring tendon graft. Sgaglione(23) et al has reported this complication in up to 70% of the cases. Making an oblique incision instead of the usual vertical incision reduced its incidence(24). De Padua et al (25) had shown that harvesting semitendinosis alone reduces the incidence of nerve injury
Since bone to tendon healing takes longer time rehabilitation after its usage is prolonged. To enhance the incorporation of hamstring tendon people are injecting platelet rich plasma into the tunnels before fixing the hamstring grafts(26). Platelet rich plasma which is supposed to contain numerous growth factors will enhance the bone to tendon healing. But there is no clear cut evidence for this till now. Weakness of knee flexion is also a concern after hamstring tendon graft harvest. However Lipscomb et al(27) had shown that harvesting the both tendons does not affect the knee flexors strength
When compared to patellar tendon graft which has a bone plug, hamstring tendon grafts are known to cause more tunnel widening. L’Insalta et al(28) in their study of 60 patients who underwent ACL reconstruction observed a significantly increased tunnel widening in the group of patients with hamstring tendon graft compared with the other group of patellar tendon grafts. But it doesn’t seem to affect the clinical outcome; although it might cause problems during a revision procedure. In a study done by Clatworthy et al(29) comparing the hamstring tendon graft with the patellar tendon graft there was no significant difference in outcome even though tunnel widening was significantly more in the hamstring tendon group.

Quadriceps tendon graft
Quadriceps tendon graft usage was first reported by Fulkerson and Langeland(30) in 1995. Gradually its usage started to increase. But still today it is the least commonly used tendon autograft for ACL reconstruction. The ultimate tensile strength of this graft is more than the native ACL and that of patellar tendon graft(31). It has been shown in a MRI study that a 10mm central strip of quadriceps tendon has 88 percent more volume than a 10mm central strip of patellar tendon(32). There are evidences that volume of the graft directly correlates with the structural properties of the incorporated graft, and also an increased failure rate with decreased graft size(33-34). Similar to patellar tendon graft the major problem with this type of graft is the donor site morbidities like pain and patella fracture. Patella fracture remains a possibility after this graft harvest. In order to reduce this complication people have modified the graft harvesting technique. Quadriceps tendon graft without the bone plug was tried and found to give comparable results(35). But the bone to bone healing which this grafts provide will be lost and the length of the graft will be reduced. The natural insertion of this tendon into the patella is not in the middle but slightly lateralized. So if we go by the centre of the patellar tendon then the bone plug in the patella will be more lateral. According to Scully et al(36) harvesting this bone plug from a slightly lateral portion of patella will predispose to fractures. So they devised a technique to medialize the graft harvest centering over to patella to obtain a bone plug from the middle of the patella. Despite improved harvesting techniques quadriceps graft is less commonly used because of the donor site morbidities. But it provides a valuable option when the other two more commonly used tendons are not available for some reason

2. Allograft
Rise of the allograft occurred in order to reduce the donor site morbidity, reduce postoperative pain and operative time. Eugene Bircher(37) was the first to use this in 1929. He used tendons harvested from kangaroo as an augment or a sole graft. Following this there were few others who used xenografts after which it became unpopular. Then was the time of allografts from human cadavers. Achilles tendon, tibialis anterior, tibialis posterior, hamstrings and patellar tendon were the major allografts harvested from cadavers for ligament reconstruction. But the increase in parenteral viral infection led to its unpopularity in the nineties. The sterilization processes like high dose radiation and ethylene glycol available during those periods affected the mechanical properties of the graft. Many studies have been published which demonstrated the deleterious effect of irradiation and ethelene oxide on allograft(38-39). Improved sterilization techniques and screening techniques revived the allograft in recent times. Data suggests that in 2002 an approximate one million musculoskeletal allografts were used in United States alone as against only 350,000 were used in 1990(40). The Bio Cleanse tissue sterilization system(41) is a recently available system which doesn’t affect the mechanical properties of the allograft. It is combination of mechanical and chemical techniques. The graft is subjected to an oscillating positive and negative pressure and treated with chemical agents like detergents and sterilants. This process removes the blood and lipids and destroys the microorganisms. The graft is repeatedly rinsed when the debris and the residual chemicals were removed. Non irradiated grafts are being favored over irradiated grafts in recent times. Prodromoset al(42) did a meta analysis and found that irradiated grafts have an abnormal stability rate in comparison to non irradiated grafts. Apart from transmission of infection from donor to the reciepient, bacterial contamination while processing and preserving these allografts was also a concern. But Greenberg et al[43] showed there was no increased risk of infection with the use of allograft compared with autograft in primary anterior cruciate ligament reconstruction. Most important problem with allograft is slow incorporation of the allograft tissue to bone and decreased failure load till it gets incorporated into the host. Many animal studies and MRI studies in humans have demonstrated this(44-46). Immunogenic reaction of the host to the graft tissue is one more possible complication. Literature evidence regarding the outcome and revision rates of allograft was not always uniform. In a meta-analysis done by Yao et al(47) there was no significant difference in patient reported outcomes scores, range of motion or the tests for laxity between BPTB autograft and allograft. But the revision rates were significantly higher in the allograft groups. Mariscalco et al(48) did a meta-analysis and compared non irradiated allografts with autografts and found no difference between the two in terms of graft failure rates, postoperative laxity and patient reported outcome scores. However allografts are not routinely used because of the cost and availability. Allograft could be the answer when the donor site morbidities and operative time have to be reduced. Improved harvest and storage techniques will increase the availability of the allografts in future

3. Synthetic grafts
Further in line are the synthetic grafts. Synthetic graft is an artificial graft prepared for two purposes. They can either act as the sole graft scaffold over which fibrous tissues develop to provide the stability as that of the native ACL. Or it can be used as a load sharer until the autograft tissue heals and take over the role. To perform this synthetic graft should be chemically stable, biocompatible, should not contain harmful additives, should not be hygroscopic and should contain pores for fibroblasts ingrowths. Above all they should have the physical characters of plasticity, stiffness, strength and traction resistance similar to the original ligament. The drawbacks associated with today’s synthetics are adverse immunological reaction, debris dispersion, failure of ligamentization process, breakage, synovitis and chronic effusion. Synthetics made of carbon were the first to enter the market. Jenkins et al(49) developed a carbon made synthetic ligament in 1977. It was initially employed for tendon suturing and later extended to knee ligament reconstruction surgeries. Dandy et al(50) were the first to introduce synthetic grafts in ACL reconstruction. His graft was also made of carbon fibers. Initially these carbon made synthetic grafts were received well, but later they went into disrepute because of early failure due to incompetency to resist torsion forces, inflammatory synovitis and carbon deposition in liver. Came next was the graft made of single strand of polytetraflouroethelene wounded into multiple loops(PTFE/ Gore-tex). Initially this was approved by the US government to be used in cases with failed autografts. It was perceived as the complete graft because of its tensile strength of 5300N, greatest of all synthetic grafts manufactured till date(51). But soon later studies found its deficiencies. After some initial encouraging results Woods et al(52) observed worsening knee stability in long term. Similarly Ferkel et al(53) performed a second look arthroscopy 11 months after 21 ACL reconstructions and found partial damage in 6 cases and complete damage in 4 cases. Soon Gore-tex was withdrawn from the market due to higher failure rate and complications like tunnel osteolysis and deposition of the PFTE particles in lymph nodes.Dacron graft made of polyester was one more product of this breed. It was made up of polyester and had an 8mm sleeve of loosely woven velour and a central core of four tightly woven tapes with a mean strength of 3631N(54). It was first used in acromio-clavicular injuries and later in ACL reconstruction. But this too failed in the long run due to high failure rates.The augmentation concept of synthetics was first given by John Kennedy in 1975 when he introduced a polypropylene ribbon for augmenting the autograft.51 This concept tried providing a support for the autografts until the healing becomes complete. The Leeds-Keio ligament(55) or the LK ligament developed in 1982 with the collaboration of Leeds university of UK and Keio university of Japan met with little success. It was made up of woven polyester fibers in tubular bundle and measured 10 mm in diameter. It acted as a scaffold and induced tissue growth. Porous coating over it allowed the tissue to grow in and form a new ligament. This too failed after it made an early impact. Murray and Macnicol(56) made a long term follow up of 10 to 16 years following ACL reconstruction with LK ligament and found a high failure rate of 28 percent and increased degenerative changes compared with the opposite side.
However the most successful of all the synthetic grafts was the Ligament Advanced Reinforcement system (LARS ligament) made up of polyethylene terephthalate(57). This also acted as a scaffold over which tissue in growth occurs. Its short term follow up showed encouraging results but the long term results are still awaited. Liu et al(58) retrospectively made a comparison between LARS and four strands hamstring tendon autografts and observed excellent functional outcomes and higher knee stability in LARS. Polyethylene teraphthalate materials were most commonly used to augment the tissue grafts. Despite repeated failures synthetic grafts continues to evolve over time and manufacturers kept pulling out a new product out of their sleeve every now and then. Confidence over the synthetics is still maintained because of the few studies which showed promising results(55, 57-58).
4. Tissue engineered grafts
This could be the future of ligament reconstruction surgeries. This technology was originally devised to repair skin, cartilage and bones but could be extended to ligaments in the near future. Tissue engineering is basically a combination of engineering, molecular biology and medical knowledge to create biological tissues or organ in vitro. Here organ or tissue growth is done in vitro over a scaffold(59). It is made by nanotechnology which produces a biomimetic structure to replicate the native architecture of the tendon extracellular matrix. Extracellular matrix of the tendon is made up of interconnected porous microstructure composed of collagen fibers. This scaffold provides the structural support over which cells grows due to chemical and mechanical stimulus. The scaffold used will be biodegradable and biocompatible along with the desired biomechanical properties. Both natural and synthetic scaffolds are being used. Collagen, silk, hyaluronic acid are examples of naturally available scaffolds while Dacron polyester, polyglycolic acid and polylactic acid are examples of synthetic scaffolds. Once the engineered graft is taken up the scaffold will gradually degrade and the cells should take over their place. Cells employed here can be mesenchymal stem cells or a tenocyte. In a study done by Kryger et al(60) tenocytes, bone marrow derived mesenchymal stem cells, adipose tissue derived mesenchymal stem cells and tendon sheath fibroblast were seeded into acellularised tendon tissue and implanted in vivo into a flexor tendon defect. After 6 weeks histological analysis revealed viable cells in all four types. But the mechanical property of each type was not analyzed.Best cells to be employed for engineering a tendon is still not clear. Currently no case of ACL was operated with a tissue engineered graft as this is a newly developing technology. Gene therapy will come to play a role in tissue engineered ACL grafts. Currently gene therapy is being researched in repairing tendon injuries(61) and the same can be applicable in ligament injuries. There are two different strategies in gene therapy(62). One is in vivo transfer of the gene within a vector which is then directly applied to the target tissues. Lou et al(63) used BMP-12 gene to treat complete tendon laceration in chicken model and found a two fold increase in tensile strength and stiffness of the repaired tendon. The disadvantage of this strategy is that there is always a possibility of transfecting the cells adjacent to the target tissue. Another disadvantage is the development of immune response to the vector. The second strategy involves harvesting the target tissues from the body, trasfecting them with the vector and then allow them to grow in a culture in vitro. Once the tissue gets matured they can be transferred to the target area. This approach seems very promising for ligament reconstruction surgeries. The idea of using stem cells in ligament injuries can become feasible in the near future. Stem cells could be harvested and induced to grow a particular mesenchymal lineage to repair the injured ligament.


conclusions

Tendon grafts continue to be the commonly used material for ACL reconstruction surgeries. Both autografts and allografts have its own pros and cons. Each surgical case should be individualized and the choice of the graft should be made. Allografts usage continues to grow. In the future with appropriate precautions this might become a major source for ACL reconstruction. Synthetic grafts and tissue engineered grafts are still in the developing phase. The usage of these grafts has a long way to go. Till then autografts and allografts are the choices of graft for ACL reconstruction.


References

1.Jones KG. Reconstruction of the anterior cruciate ligament using the central one-third of the patellar ligament. Journal of Bone and Joint Surgery Am. 1970;52(4):838–9.
2.Noyes FR, Butler DL, Grood ES, et al. Biomechanical analysis of human ligament grafts used in knee-ligament repairs and reconstructions. J Bone Joint Surg Am. 1984; 66:344-52.
3.Benjamin M, Ralphs JR. Fibrocartilage in tendons and ligaments. An adaption to compressive load. J Anat. 1998; 193:481-94.
4.Petersen W, Laprell H. Insertion of autologous tendon grafts to the bone: a histological and immunohistochemical study of hamstring and patellar tendon grafts. Knee Surg Sports Traumato Arthrosc. 2000;8:26-31.
5.Sharpey W, Ellis GV. Elements of anatomy by Jones Quain. 6.vol1. London: Walton and Moberly;1856.
6.Li SZ, Su W, Zhao J et al. A meta-analysis of hamstring autografts versus bone–patellar tendon–bone autografts for reconstruction of the anterior cruciate ligament. The Knee. 2011;18:287–93.
7.Franke K. Clinical experience in 130 cruciate ligament reconstructions. Orthopedic Clinics of North America. 1976; 7(1):191–3.
8.Plancher KD, Steadman JR, Briggs KK, Hutton KS. Reconstruction of the anterior cruciate ligament in patients who are at least forty years old.A long-term follow-up and outcome study. J Bone Joint Surg Am. 1998;80:184–97.
9.Shaieb MD, Kan DM, Chang SK, Marumoto JM, Richardson AB. A prospective randomized comparison of patellar tendon versus semitendinosus and gracilis tendon autografts for anterior cruciate ligament reconstruction. Am J Sports Med. 2002;30:214–20.
10.Berg P, Mjoberg B. A lateral skin incision reduces peripatellar dysaesthesia after knee surgery. J Bone Joint Surg Br. 1991;73:374–6.
11.Liu SH, Hang DW, Gentili A, Finerman GA. MRI and morphology of the insertion of the patellar tendon after graft harvesting. J Bone Joint Surg Br. 1996;78:823–6.
12.Kartus J, Movin T, Karlsson J. Donor-site morbidity and anterior knee problems after anterior cruciate ligament reconstruction using autografts. Arthroscopy. 2001;17:971–80.
13.Brandsson S, Faxen E, Eriksson BI et al. Closing patellar tendon defects after anterior cruciate ligament reconstruction: absence of any benefit. Knee Surg Sports Traumatol Arthrosc. 1998;6:82–7.
14.Coupens SD, Yates CK, Sheldon C, Ward C. Magnetic resonance imaging evaluation of the patellar tendon after use of its central one-third for anterior cruciate ligament reconstruction. Am J Sports Med. 1992;20:332–5.
15.Meisterling RC, Wadsworth T, Ardill R, Griffiths H, Lane-Larsen CL. Morphologic changes in the human patellar tendon after bone-tendon-bone anterior cruciate ligament reconstruction. Clin Orthop Relat Res 1993;289:208–12.
16.Nixon RG, SeGall GK, Sa SL, Cain TE, Tullos HS. Reconstruction of the patellar tendon donor site after graft harvest. Clin Orthop Relat Res. 1995;317:162–71.
17.Hulstyn M, Fadale PD, Abate J, Walsh WR. Biomechanical evaluation of interference screw fixation in a bovine patellar bone-tendon-bone autograft complex for anterior cruciate ligament reconstruction. Arthroscopy. 1993;9(4):417–24.
18.K Marimuthu, N Joshi, M Sharma. Anterior cruciate ligament reconstruction using the medial third of the patellar tendon. Journal of Orthopaedic Surgery. 2011;19(2):221-5.
19.Strickland SM, MacGillivray JM, Warren RF. Anterior cruciate ligament reconstruction with allograft tendons. Orthopedic Clinics of North America. 2003;34(1):41–47.
20.Macey H. A new operative procedure for the repair of ruptured cruciate ligaments of the knee joint. Surgery, Gynecology &Obstetrics. 1939;69:108–9.
21.Lindemann K. Plastic surgery in substitution of the cruciate ligaments of the knee-joint by means of pedunculated tendon transplants. Zeitschriftf¨urOrthop¨adie und ihreGrenzgebiete. 1950;79(2):316–34.
22.Augustine RW. The unstable knee. The American Journal of Surgery. 1956;92(3):380–8.
23.Sgaglione NA, Warren RF, Wickiewicz TL, Gold DA, Panariello RA. Primary repair with semitendinosus tendonaugmentation of acute anterior cruciate ligament injuries. Am J Sports Med. 1990;18(1):64–73.
24.Luo H, Yu JK, Ao YF et al. Relationship between different skin incisions and the injury of the infrapatellar branch of the saphenous nerve during anterior cruciate ligament reconstruction. Chin Med J (Engl).2007;120(13):1127–30.
25. De Padua VBC, Nascimento PED, Silva SC et al. Saphenous nerve injury during harvesting of one or two hamstring tendons for anterior cruciate ligament reconstruction. Rev Bras Ortop. 2015 Sep-Oct; 50(5): 546–9.
26.Figueroa D, Melean P, Calvo R et al. Magnetic Resonance Imaging Evaluation of the Integration and Maturation of Semitendinosus-Gracilis Graft in Anterior Cruciate Ligament Reconstruction Using Autologous Platelet Concentrate. Arthroscopy: The Journal of Arthroscopic and Related Surgery. 2010;26(10):1318-25.
27. Lipscomb AB, Johnston RK, Snyder RB, Warburton MJ, Gilbert PP. Evaluation of hamstring strength following use of semitendinosus and gracilis tendons to reconstruct the anterior cruciate ligament. Am J Sports Med. 1982 Nov-Dec;10(6):340-2.
28. L’Insalata JC, Klatt B, Fu FH, Harner CD. Tunnel expansion following anterior cruciate ligament reconstruction: A comparison of hamstring and patellar tendon autografts. Knee Surg Sports Traumatol Arthrosc. 1997;5:234-8.
29. Clatworthy MG, Annear P, Bulow JU, Bartlett RJ. Tunnel widening in anterior cruciate ligament reconstruction: A prospective evaluation of hamstring and patella tendon grafts. Knee Surg Sports Traumatol Arthrosc. 1999;7:138-145.
30.Fulkerson JP, Langeland R. An alternative cruciate reconstruction graft: The central quadriceps tendon. Arthroscopy. 1995;11:252-4.
31.West RV, Harner CD. Graft selection in anterior cruciate ligament reconstruction. J Am Acad Orthop Surg. 2005;13:197-207.
32.Xerogeanes JW, Mitchell PM, Karasev PA, Kolesov IA, Romine SE. Anatomic and morphological evaluation of the quadriceps tendon using 3-dimensional magnetic resonance imaging reconstruction: Applications for anterior cruciate ligament autograft choice and procurement. Am J Sports Med. 2013;41:2392-9.
33. Magnussen RA, Lawrence JT, West RL et al. Graft size and patient age are predictors of early revision after anterior cruciate ligament reconstruction with hamstring autograft. Arthroscopy. 2012;28:526-31.
34. Teli M, Chiodini F, Sottocasa R, Villa T. Influence of the diameters of tendon graft and bone tunnel in hamstring ACL reconstruction. A bovine model. Chir Organi Mov. 2005;90:281-5.
35.Fulkerson J, McKeon B, Donahue B. The central quadriceps tendon as a versatile graft alternative in anterior cruciate ligament reconstruction: Techniques and recent observations. Tech Orthop. 1998;13:367-74.
36.Scully WF, Wilson DJ and Arrington ED. Central Quadriceps Tendon Harvest With Patellar Bone Plug: Surgical Technique Revisited. Arthroscopy Techniques. 2013;2(4)Nov:e427-32.
37. Bircher E. ÜberKreuzbandverletzungen [On cruciate ligament injuries]. Zentralbl Chir. 1930; 57: 220-7.
38. Roberts TS, Drez D Jr, McCarthy W, Paine R. Anterior cruciate ligament reconstruction using freeze-dried, ethylene oxide-sterilized, bone-patellar tendon-bone allografts. Two year results in thirty-six patients. Am J Sports Med. 1991;19:35-41.
39. Fideler BM, Vangsness CT Jr, Lu B, Orlando C, Moore T. Gamma irradiation: effects on biomechanical properties of human bone-patellar tendon-bone allografts. Am J Sports Med. 1995;23:643-6.
40. Organ transplants and grafts, 1990-2000. No. 161. In: Statistical abstracts of the United States: 2003. Washington, DC: Census Bureau; 2002. p 113.
41.Vangsness CT Jr, Garcia IA, Mills CR et al. Allograft transplantation in the knee: tissue regulation, procurement, processing, and sterilization. Am J Sports Med.2003;31(3):474–81.
42.Prodromos C, Joyce B, Shi K. A meta-analysis of stability of auto-grafts compared to allografts after anterior cruciate ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2007; 15(7):851–6.
43.Greenberg DD, Robertson M, Vallurupalli S, White RA and Allen WC. Allograft Compared with Autograft Infection Rates in Primary Anterior Cruciate Ligament Reconstruction. J Bone Joint Surg Am. 2010;92:2402-8.
44.Jackson DW, Grood ES, Goldstein JD et al. A comparison of patellar tendon autograft and allograft used for anterior cruciate ligament reconstruction in the goat model. Am J Sports Med. 1993;21(2):176–85.
45.Nagano J, Shino K, Maeda A, Nakata K, Horibe S. The remodelling process of allogeneic and autogenous patellar tendon grafts in rats: a radiochemical study. Arch Orthop Trauma Surg. 1996;115(1):10–6.
46.Muramatsu K, Hachiya Y, Izawa H. Serial evaluation of human anterior cruciate ligament grafts by contrast-enhanced magnetic resonance imaging: comparison of allografts and autografts. Arthroscopy. 2008;24(9):1038–44.
47. Yao LW, Wang Q, Zhang L et al. Patellar tendon autograft versus patellar tendon allograft in anterior cruciate ligament reconstruction: a systematic review and meta-analysis. Eur J Orthop Surg Traumatol. 2015 Feb;25(2):355-65.
48.Mariscalco WN, Magnussen RA, Mehta D et al. Autograft Versus Nonirradiated Allograft Tissue for Anterior Cruciate Ligament Reconstruction: A Systematic Review. Am J Sports Med. 2014 Feb; 42(2): 492–9.
49.Jenkins DHR, Forster IW, McKibbin B, and Ralis ZA. Induction of tendon and ligament formation by carbon implants. Journal of Bone and Joint Surgery Br. 1977;59(1):53–7.
50. Dandy DJ, Flanagan JP, Steenmeyer V. Arthroscopy and the management of the ruptured anterior cruciate ligament. Clin Orthop. 1982;167:43–9.
51.McCarthy DM, Tolin BS, Schwenderman L, Friedman MJ, Woo SL-Y. (1993)Prosthetic replacement for the anterior cruciate ligament. In: Jackson DW (ed) The anterior cruciate ligament: current and future concepts. Raven Press Ltd, New York, pp 343–356.
52. Woods GA, Indelicato PA, Prevot TJ. The Gore-Tex anterior cruciate ligament prosthesis: two vs. three years results. Am J Sports Med. 1991; 19:48–55.
53. Ferkel RD, Fox JM, Wood D et al. Arthroscopic “second look” at the Gore-Tex ligament. Am J Sports Med. 1989;17:147–53
54. Lukianov AV, Richmond JC, Barrett GR, Gillquist J. A multicenter study on the results of anterior cruciate ligament reconstruction using a Dacron ligament prosthesis in “salvage” cases. Am J Sports Med. 1998;17:380–6.
55.Fujikawa K (1988) Clinical study of anterior cruciate ligament reconstruction with the Leeds-Keio artificial ligament. In: Friedman MJ (ed) Prosthetic ligament reconstruction of the knee. WB Saunders, Philadelphia, PA.
56.Murray AW, Macnicol MF. 10–16 year results of Leeds-Keio anterior cruciate ligament reconstruction. Knee. 2004;11:9–14.
57.Lavoie P, Fletcher J, Duval N. Patients satisfaction needs as related to knee stability and objective findings after ACL reconstruction using the LARS artificial ligament. Knee. 2000; 7:157–63.
58.Liu ZT, Zhang XL, Jiang Y, Zeng BF. Four-strand hamstring tendon autograft versus LARS artificial ligament for anterior cruciate ligament reconstruction. Int Orthop. 2009; doi:10.1007/s00264-009-0768-3.
59.Yang, S., et al. The Design of Scaffolds for Use in Tissue Engineering. Part I. Traditional Factors. Tissue Engineering. 2001;7(6):679-89.
60.Kryger G et al. A Comparison of Tenocytes and Mesenchymal Stem Cells for Use in Flexor Tendon Tissue Engineering. The Journal of Hand Surgery. 2007;32(5): 597-605.
61. Bolt P et al. BMP-14 Gene Therapy Increases Tendon Tensile Strength in a Rat Model of Achilles Tendon Injury. Journal of Bone and Joint Surgery Am. 2007;89(6):1315-20.
62. Huang D, Balian G, and Chhabra A. Tendon Tissue Engineering and Gene Transfer: The Future of Surgical Treatment. The Journal of Hand Surgery. 2006;31(5): 693-704.
63.Lou J. and Y.T.M.B.M.J.S.P. Manske. BMP-12 gene transfer augmentation of lacerated tendon repair. Journal of Orthopaedic Research. 2001;19(6):1199-202.


How to Cite this article:. Sundararajan SR,  Sambandam B, Rajasekaran S. Future Trends In Grafts Used In ACL Reconstruction. Asian Journal of Arthroscopy  Apr- June 2016;1(1):29-34 .

Dr. Sundararajan S R

Dr. Sundararajan S R

Dr. Balaji Sambandam

Dr. Balaji Sambandam

Dr. S Rajasekaran

Dr. S Rajasekaran


(Abstract)      (Full Text HTML)      (Download PDF)


Biologics in Primary Anterior Cruciate Ligament Reconstruction

Vijay D Shetty, Karan Alva, Varun Gupta

Volume 1 | Issue 1 | April – Jun 2016 | Page 25-28


Author: Vijay D Shetty [1], Karan Alva [1], Varun Gupta [1]

[1] LH Hiranandani Hospital, Hiranandani Orthopaedic Medical Education (HOME), Mumbai 400 076,India.

Address of Correspondence

Dr Vijay D Shetty
Dr LH Hiranandani Hospital
Hiranandani Orthopaedic Medical Education (HOME)
Mumbai 400 076 India
Email id – vijaydshetty@gmail.com


Abstract

The success of anterior cruciate ligament reconstruction depends on the healing and integration of the graft in the bony tunnels. Recently there has been lot of interest in biological augmentation techniques to improve the biological milieu in the knee joint so as to enhance this healing process. These techniques include use of platelet rich plasma, periosteum and bone morphogenetic proteins (BMPs). The present article is a review of current literature exploring the effectiveness of these techniques and the future scope
Keywords: anterior cruciate ligament reconstruction, platelet rich plasma, bone morphogenetic proteins


Introduction

The anterior cruciate ligament (ACL) is the most commonly injured knee ligament, frequently requiring surgery and extensive rehabilitation(1). Primary repair of the ACL has a high failure rate of 40% to 100% mandating the need for ACL reconstruction (ACLR)(2). However, success of ACLR depends mainly on the healing and integration of graft into the femoral and tibial tunnels(3,4,5). Various factors such as graft selection, graft incorporation and pre-injury activity level influence the clinical outcome of ACLR(6,7). Studies have shown that younger the age of the patient and, more athletic the demand, higher is the expectation from the surgery(8,9).
Graft-bone healing has been always an issue with ACLR. Recent years have seen a number of publications indicating the use of biological augmentation techniques to enhance graft-bone healing(10,11). These include the use of platelet rich plasma, periosteum and bone morphogenetic proteins (BMPs). This article attempts to explore the current thinking in the use of biologics in enhancing bone-graft healing in ACLR.

Graft healing
Natural healing of torn ACL is one of the challenging problems encountered by surgeons. The hypo-vascular and hypo-cellular nature of ACL retards its self regeneration capacity and results in poor healing. Further, following ACL injury, the thin synovial sheath surrounding the ACL gets disrupted resulting in mixing of blood with the native synovial fluid. As a result, haematoma formation is delayed and this prevents the aggregation of factors (cytokines, growth factors and reparative cells) responsible for natural healing(12). This forms the basis of non-healing of injured ACL. Therefore, the best option to address this issue would be a reconstruction rather than repair.
Normally, ACL inserts directly into the bone, thus forming a transition zone from the tendon-to-bone consisting of the tendon, non-mineralized fibrocartilage, mineralized fibrocartilage and bone (Figure 1). The fibrocartilage at the insertion site contains cartilage-specific collagens, type II, IX, X and XI, with the interface between mineralized and demineralized bone maintained by collagen X(13). Besides, obliquely running Sharpey fibres are present at insertion sites which anchors the ligament to bone, providing the fundamental mechanical strength. ACLR with tendon grafts fails to reproduce the same arrangement. It has been shown by various studies that graft healing in ACLR occurs by an interposed layer of fibro-vascular scar tissue at the graft tunnel site(14). This fibro-vascular scar tissue becomes mineralized and incorporates the tendon graft into the surrounding bone. The tendon bone junction is restored by the re-growth of collagen fibres between the tendon and bone(15,16,17,18,19). The formation of collagens and Sharpey fibres occurs after 6 weeks of surgery and bone tunnel healing of graft is completed by 6-10 months after surgery(20). However poor osteo-integration of the graft in ACLR is common and is associated with anterior –posterior laxity postoperatively (21). Thus, to achieve earlier return to functional activities and better clinical outcomes, acceleration of healing between tendon graft and bone is the most enduring challenge. In order to improve graft bone healing, various biologically engineered strategies are being studied. These biological strategies aim to enhance intra-articular and intra-osseous healing.

Figure 1: Organised transition from tendon (T) to demineralised fibrocartilage (UFC) to mineralized fibrocartilage (MFC) and bone (B). Courtesy: Muller et al, 2013.

Figure 1: Organised transition from tendon (T) to demineralised fibrocartilage (UFC) to mineralized fibrocartilage (MFC) and bone (B). Courtesy: Muller et al, 2013.

Figure 2: The periosteum is wrapped with the cambium layer facing the tunnel wall and then sutured on the tendon at both sides with a No. 3-0 Vicryl suture where the tendon graft approached the tunnel opening. Courtesy: Chen at al, 2010.

Figure 2: The periosteum is wrapped with the cambium layer facing the tunnel wall and then sutured on the tendon at both sides with a No. 3-0 Vicryl suture where the tendon graft approached the tunnel opening. Courtesy: Chen at al, 2010.

Biological strategies to enhance tendon graft healing in ACLR
Platelet-rich plasma
Platelet-rich plasma (PRP) is an autologous concentration of platelets. The concentration of these platelets, in a given formulation, is much above the normal physiological levels. Platelets are the precursors of the megakaryocytes having an irregular shape with non-nucleated cytoplasmic bodies. The glycoprotein’s expressed on their cell membranes play an important role in haemostasis and wound healing by formatting fibrin clots(22). Platelets are the source of various growth factors including platelet-derived growth factor (PDGF), epidermal growth factor (EGF), transforming growth factor-beta 1 (TGF-β1), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF), hepatocyte growth factor (HGF), and insulin-like growth factor (IGF-I) which are involved in different stages of cell proliferation(23,24,25).
Versatility of PRP lies in the fact that it can be easily prepared and can be applied directly in the operation theatre. Various methods of its application are intra- articular injection or in the form of a membrane that can be applied directly to target site. Several studies have shown that the healing potential of PRP in articular tissues, cartilage, ligaments, tendons and synovium(26,27,28). Infiltration of PRP causes increase in the extracellular matrix deposition, anabolic reaction towards cells, reduction of pro apoptotic signals and also has anti–inflammatory effect in the joint environment(26). Studies have shown that application of PRP in ACL reconstruction procedure not only causes better and faster ligamentization of the graft, but also contributes to a better integration of the graft within the bone tunnels. Enlargement of bone tunnels can thus be prevented and faster healing can be promoted.

Periosteum
Periosteum is a bilayered tissue between the bone and soft tissue. It had an outer fibrous layer which is rich in fibroblasts while the inner cambium layer is rich in multipotent mesodermal cells. It also consists of chondro-progenitor and osteo-progenitor cells, which can differentiate into both cartilage and bone(29,30). It can be easily harvested at the proximal tibia from a routine incision for hamstring tendon harvesting (Figure 2). The tendon reconstruction is said to be successful if there is bony in-growth into the tendon.8 The periosteum may be used to enhance the healing between the bone and graft by forming fibrocartilage and calcified fibrocartilage(31,32). Besides, it can also help to seal the intra-articular tunnel opening in the early postoperative period, thus avoiding synovial fluid reflux into the tunnel(33,34). Studies have shown favourable outcome with the use of periosteum to enhance tendon-bone healing post ACLR. In a study by Chen et al, (31) knees were followed up for a mean of 4.6 years post ACLR which showed statistically significant results with periosteum-enveloping hamstring tendon single bundle ACLR when compared to other studies with comparable fixation(35).

Bone morphogenetic protein
Bone morphogenetic proteins (BMPs) are signalling proteins which interact with tissue structures in the body to enhance the skeletal development. Animals studies have shown that both BMP-2 and BMP-7 have the ability to increase the graft fixation strength in bone tunnels(36,37,38). A study by Sunder S et al in bovine models showed that demineralised bone matrix (DBM) is a source of BMPs which enhances tendon-bone healing and tendon-bone fixation strength(39). Further, Chen CH et al concluded that BMP-2 and periosteal progenitor cells induce rapid tendon-bone integration(21). However, there is much debate about the use of BMPs in ACLR surgeries in human being despite the theoretical advantages(21).

Discussion
The main goal of ACLR is to make the patient return to pre-injury level, and therefore return to sports, as soon as possible. In this direction, there have been a number of technological advances, in recent years, with respect to ACLR. Last few years have seen an increase in the number of publications on best surgical techniques, anatomical tunnel placements, use of scaffolds and augmentation with various biological products. Enhancing the tendon-to-bone healing has been the centre of research in ACLR(28,40,41).
It has been established that the tendon-bone healing occurs by collagen fibre scarring tissue which then reorganises to form a dense matrix. This is then followed by the appearance of Sharpey’s fibres. This collagen fiber continuity between the tendon and bone establishes the tendo-osseous junction and has been described as the earliest sign of osteo-integration(42,43).
Periosteum is rich in multipotent mesodermal cells and has osteogenic capacity. It has the ability to promote cartilage formation and also initiate enchondral ossification by inducing differentiation of mesenchymal cells into chondroblasts and subsequently into osteoblasts. It can also augment bone ingrowth into collagenous tissue and help induce ossification. When we incorporate periosteum in our graft by suturing on the surface of the tendon and then transplanting into the bony tunnel, the cambium layer of the periosteum serves as a fibrous layer between the tendon and bone interface. Studies have shown that by around 4 weeks, there is inter-digitation between the periosteum tissue and tendon resulting in progressive incorporation over time. Because of the effect of periosteum on promoting bony ingrowth and increasing the strength of the fixation, enveloping the tendon with it may be an effective way to enhance graft incorporation. Tunnel widening following ACLR is significantly greater with hamstring tendon. This is attributed to the greater distance from the normal insertion site and biomechanical point of action of the ACL, creating a larger force moment during graft cycling leading to greater expansion of the tunnels (44)
Platelet-rich plasma is another biological product that is frequently used to enhance tendon bone healing in ACLR. A prospective study by Radice et al compared the MRI findings between ACLR with biological augmentation and without biological augmentation(45). Post-operative MRIs showed that a 48% of time shortening, in healing, was achieved in augmentation group. Another study by Magnussen et al (46) compared 50 patients of allograft ACLR supplemented with platelet rich plasma, intra-operatively, with 50 patients of allograft ACLR without the use of platelet rich plasma using similar operative techniques. The results showed minor short-term clinical benefits, with biological augmentation, at two year post surgery. This, perhaps, indicates that biological augmentation is not that promising when allografts are used for ACLR. Further, a study by Mirzatolooei et al (47) evaluated tunnel diameters, in augmentation group and non-augmentation group, using CT scans on the day of surgery and at three months after surgery. Their results did not show a statistically significant change in the tunnel diameter between the augmentation group and non-augmentation group.


Conclusions

It appears, from the available literature, that biological augmentation in ACLR is an attractive option. However, at the moment, there is no concrete evidence to suggest that biologics work well with allografts. Besides, the tunnel widening issue still remains a major concern in ACLR and, there is conflicting evidence to support the idea of using biologics to address tunnel widening in ACLR.   Although the jury is still out on specific advantages, it appears that there is no harm in using biologics in ACLR. It remains to be seen whether future level I studies will throw more light into the use of biological augmentation in ACLR procedures.


References

1. Kaplan N, Wickiewicz T, Warren R. Primary surgical treatment of anterior cruciate ligament ruptures: A long-term follow-up study. The American Journal of Sports Medicine. 1990;18(4):354-358.
2. Strand T, Molster A, Hordvik M, Krukhaug Y. Long-term follow-up after primary repair of the anterior cruciate ligament: clinical and radiological evaluation 15 – 23 years postoperatively. Arch Orthop Trauma Surg. 2004;125(4):217-221.
3. Spindler K, Huston L, Wright R, Kaeding C, Marx R, Amendola A et al. The Prognosis and Predictors of Sports Function and Activity at Minimum 6 Years After Anterior Cruciate Ligament Reconstruction: A Population Cohort Study. The American Journal of Sports Medicine. 2010;39(2):348-359.
4. Murray MM, Martin SD, Martin TL, Spector M. Histological changes in the human anterior cruciate ligament after rupture. J Bone Joint Surg Am. 2000 Oct;82-A(10):1387-97.
5. Visconti C, Kavalkovich K, Wu J, Niyibizi C. Biochemical Analysis of Collagens at the Ligament–Bone Interface Reveals Presence of Cartilage-Specific Collagens. Archives of Biochemistry and Biophysics. 1996;328(1):135-142.
6. Niyibizi C, Sagarrigo Visconti C, Gibson G, Kavalkovich K. Identification and immunolocalization of type X collagen at the ligament-bone interface. Biochem Biophys Res Commun. 1996;222:584-589.
7. Oguma H, Murakami G, Takahashi-Iwanaga H, Aoki M, Ishii S. Early anchoring collagen fibers at the bone—tendon interface are conducted by woven bone formation: light microscope and scanning electron microscope observation using a canine model. Journal of Orthopaedic Research. 2001;19(5):873-880.
8. Rodeo SA, Arnoczky SP, Torzilli PA, Hidaka C, Warren RF. Tendon-healing in a bone tunnel. A biomechanical and histological study in the dog. J Bone Joint Surg Am. 1993 Dec;75(12):1795-803.
9. Grana WA, Egle DM, Mahnken R, Goodhart CW. An analysis of autograft fixation after anterior cruciate ligament reconstruction in a rabbit model. Am J Sports Med. 1994;22:344e351.
10. Lui P, Zhang P, Chan K, Qin L. Biology and augmentation of tendon-bone insertion repair. Journal of Orthopaedic Surgery and Research. 2010;5(1):59.
11. Ekdahl M, Wang J, Ronga M, Fu F. Graft healing in anterior cruciate ligament reconstruction. Knee Surgery, Sports Traumatology, Arthroscopy. 2008;16(10):935-947.
12. Goradia VK, Rochat MC, Grana WA, Rohrer MD, Prasad HS. Tendon-to-bone healing of a semitendinosus tendon autograft used for ACL reconstruction in a sheep model. Am J Knee Surg. 2000 Summer;13(3):143-51.
13. Eriksson E. Vascular ingrowth into ACL-grafts. Knee Surgery, Sports Traumatology, Arthroscopy. 2008;16(4):341-341.
14. Chen C, Lee C. Biological fixation in anterior cruciate ligament surgery. Asia-Pacific Journal of Sports Medicine, Arthroscopy, Rehabilitation and Technology. 2014;1(2):48-53.
15. Gulotta L, Rodeo S. Biology of Autograft and Allograft Healing in Anterior Cruciate Ligament Reconstruction. Clinics in Sports Medicine. 2007;26(4):509-524.
16. Nebelung W, Becker R, Urbach D, Röpke M, Roessner A. Histological findings of tendon-bone healing following anterior cruciate ligament reconstruction with hamstring grafts. Arch Orthop Trauma Surg. 2003 May;123(4):158-63.
17. Weiler A, Hoffmann R, Bail H, Rehm O, Südkamp N. Tendon healing in a bone tunnel. Part II. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2002;18(2):124-135.
18. Wen C, Qin L, Lee K, Wan-Nar Wong M, Chan K. Influence of bone adaptation on tendon-to-bone healing in bone tunnel after anterior cruciate ligament reconstruction in a rabbit model. Journal of Orthopaedic Research. 2009;27(11):1447-1456.
19. Hays P. The Role of Macrophages in Early Healing of a Tendon Graft in a Bone Tunnel. The Journal of Bone and Joint Surgery (American). 2008;90(3):565.
20. Duthon V, Barea C, Abrassart S, Fasel J, Fritschy D. Anatomy of the anterior cruciate ligament. Knee Surgery, Sports Traumatology, Arthroscopy. 2006;14(3):204–213.
21. Chen C, Liu H, Tsai C, Yu C, Lin I, Hsiue G. Photoencapsulation of Bone Morphogenetic Protein-2 and Periosteal Progenitor Cells Improve Tendon Graft Healing in a Bone Tunnel. The American Journal of Sports Medicine. 2007;36(3):461-473.
22. Midwood K, Williams L, Schwarzbauer J. Tissue repair and the dynamics of the extracellular matrix. The International Journal of Biochemistry & Cell Biology. 2004;36(6):1031-1037.
23. Zhang J, Wang J. Platelet-Rich Plasma Releasate Promotes Differentiation of Tendon Stem Cells Into Active Tenocytes. The American Journal of Sports Medicine. 2010;38(12):2477-2486.
24. Bielecki T, Gazdzik T, Arendt J, Szczepanski T, Krol W, Wielkoszynski T. Antibacterial effect of autologous platelet gel enriched with growth factors and other active substances: AN IN VITRO STUDY. Journal of Bone and Joint Surgery – British Volume. 2007;89-B(3):417-420.
25. Mishra A, Harmon K, Woodall J, Vieira A. Sports medicine applications of platelet rich plasma. Curr Pharm Biotechnol. 2012 Jun;13(7):1185-95.
26. Filardo G, Kon E, Roffi A, Di Matteo B, Merli M, Marcacci M. Platelet-rich plasma: why intra-articular? A systematic review of preclinical studies and clinical evidence on PRP for joint degeneration. Knee Surgery, Sports Traumatology, Arthroscopy. 2013;23(9):2459-2474.
27. Baksh N, Hannon C, Murawski C, Smyth N, Kennedy J. Platelet-Rich Plasma in Tendon Models: A Systematic Review of Basic Science Literature. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2013;29(3):596-607.
28. Boswell S, Cole B, Sundman E, Karas V, Fortier L. Platelet-Rich Plasma: A Milieu of Bioactive Factors. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2012;28(3):429-439.
29. Ritsila VA, Santavirta S, Alhopuro S, Poussa M, Jaroma H, Rubak JM, et al. Periosteal and perichondral grafting in reconstructive surgery. Clin Orthop Relat Res 1994;302:259‑65
30. Rubak J. Osteochondrogenesis of Free Periosteal Grafts in the Rabbit Iliac Crest. Acta Orthopaedica Scandinavica. 1983;54(6):826-831.
31. Chen C, Chen W, Shih C, Yang C, Liu S, Lin P. Enveloping the tendon graft with periosteum to enhance tendon-bone healing in a bone tunnel: A biomechanical and histologic study in rabbits. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2003;19(3):290-296.
32. Youn I, Jones D, Andrews P, Cook M, Suh J. Periosteal Augmentation of a Tendon Graft Improves Tendon Healing in the Bone Tunnel. Clinical Orthopaedics and Related Research. 2004;419:223-231.
33. Chen C, Chen W, Shih C. Enveloping of Periosteum on the Hamstring Tendon Graft in Anterior Cruciate Ligament Reconstruction (SS-69). Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2002;18(5):53-54.
34. Chen C, Chen W, Shih C, Chou S. Arthroscopic anterior cruciate ligament reconstruction with periosteum-enveloping hamstring tendon graft. Knee Surgery, Sports Traumatology, Arthroscopy. 2004;12(5).
35. Chen C, Chang C, Su C, Wang K, Liu H, Yu C et al. Arthroscopic Single-Bundle Anterior Cruciate Ligament Reconstruction With Periosteum-Enveloping Hamstring Tendon Graft: Clinical Outcome at 2 to 7 Years. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2010;26(7):907-917.
36. Martinek V, Latterman C, Usas A, Abramowitch S, Woo SL, Fu FH, Huard J.Enhancement of tendon-bone integration of anterior cruciate ligament grafts with bone morphogenetic protein-2 gene transfer: a histological and biomechanical study. J Bone Joint Surg Am. 2002 Jul;84-A(7):1123-31.
37. Axelrad T, Einhorn T. Bone morphogenetic proteins in orthopaedic surgery. Cytokine & Growth Factor Reviews. 2009;20(5-6):481-488.
38. Mihelic R. Bone Morphogenetic Protein-7 (Osteogenic Protein-1) Promotes Tendon Graft Integration in Anterior Cruciate Ligament Reconstruction in Sheep. American Journal of Sports Medicine. 2004;32(7):1619-1625.
39. Sundar S, Pendegrass C, Blunn G. Tendon bone healing can be enhanced by demineralized bone matrix: A functional and histological study. Journal of Biomedical Materials Research Part B: Applied Biomaterials. 2009;88B(1):115-122.
40. Gulotta L, Wiznia D, Cunningham M, Fortier L, Maher S, Rodeo S. What’s New in Orthopaedic Research. The Journal of Bone and Joint Surgery (American). 2011;93(22).
41. Chang CH, Chen CH, Liu HW, Whu SW, Chen SH, Tsai CL, Hsiue GH. Bioengineered periosteal progenitor cell sheets to enhance tendon-bone healing in a bone tunnel. Biomed J. 2012 Nov-Dec;35(6):473-80.
42. Liu S, Panossian V, Al-Shaikh R, Tomin E, Shepherd E, Finerman G et al. Morphology and Matrix Composition During Early Tendon to Bone Healing. Clinical Orthopaedics and Related Research. 1997;339:253-260.
43. Tomita F, Yasuda K, Mikami S, Sakai T, Yamazaki S, Tohyama H. Comparisons of intraosseous graft healing between the doubled flexor tendon graft and the bone–Patellar tendon–Bone graft in anterior cruciate ligament reconstruction. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2001;17(5):461-476.
44. Fahey M, Indelicato P. Bone Tunnel Enlargement After Anterior Cruciate Ligament Replacement. The American Journal of Sports Medicine. 1994;22(3):410-414.
45. Radice F, Yánez R, Gutiérrez V, Rosales J, Pinedo M, Coda S. Comparison of Magnetic Resonance Imaging Findings in Anterior Cruciate Ligament Grafts With and Without Autologous Platelet-Derived Growth Factors. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2010;26(1):50-57.
46. Magnussen R, Flanigan D, Pedroza A, Heinlein K, Kaeding C. Platelet rich plasma use in allograft ACL reconstructions: Two-year clinical results of a MOON cohort study. The Knee. 2013;20(4):277-280.
47. Mirzatolooei F, Alamdari M, Khalkhali H. The impact of platelet-rich plasma on the prevention of tunnel widening in anterior cruciate ligament reconstruction using quadrupled autologous hamstring tendon: A randomised clinical trial. The Bone & Joint Journal. 2013;95-B(1):65-69


How to Cite this article:. Shetty VD, Alva K, Gupta V. Biologics in Primary Anterior Cruciate Ligament Reconstruction.  Asian Journal of Arthroscopy  Apr- June 2016;1(1):25-28 .

Dr Vijay D Shetty

Dr Vijay D Shetty

Dr Karan Alva

Dr Karan Alva

Dr Varun Gupta

Dr Varun Gupta


(Abstract)      (Full Text HTML)      (Download PDF)


BTB Vs Hamsrtings – Is There a Winner Yet ?

Sachin Tapasvi, Sachin Jain, Ashok Shyam

Volume 1 | Issue 1 | April – Jun 2016 | Page 11-15


Author: Sachin Tapasvi [1 ], Sachin Jain [2], Ashok Shyam [2],[3]

[1] Orthopaedic Specialty Clinic, Pune, Maharashtra. India
[2] Sancheti Institute for Orthopaedics & Rehabilitation, Pune, India
[3] Indian Orthopaedic Research Group, Thane, India

Address of Correspondence

Dr Sachin Tapasvi
Orthopaedic Specialty Clinic, Pune Maharashtra. India.
Email: stapasvi@gmail.com


Abstract

Bone patella tendon bone (BPTB) graft versus Hamstring (HT) Graft is still an issue that is debated. Both the graft have stood the test of time with high patient satisfaction however each have their own advantages and disadvantages. BPTB has advantages of good stability and bone to bone healing and disadvantage of anterior knee pain, numbness and quadriceps weakness. HT graft have advantage of less donor site morbidity, less extension deficit and disadvantage of having a slightly higher failure rate and hamstring weakness. Irrespective of these named advantages and disadvantages the patient reported outcomes are similar with both graft and difference in choice of graft is poorly understood. In this review we simply try to bring our reader up-to-date with the current literature on this controversy
Keywords: Bone patella tendon bone graft, hamstring graft, anterior cruciate ligament reconstruction.


Introduction

Anterior cruciate ligament (ACL) is required for static and dynamic stabiliser of the knee joint and purpose of ACL reconstruction is to stabilize and to resume function to maximum extent (1, 2). The ideal graft for use in anterior cruciate ligament reconstruction should have structural and biomechanical properties similar to those of the native ligament, permit secure fixation and rapid biologic incorporation, and limit donor site morbidity (3). Moreover, these properties should be present at the time of graft implantation and persist throughout the incorporation period too (3).
Graft options available are broadly grouped into autograft such as bone patellar bone tendon graft (BPTB), hamstring graft, Quadriceps graft and allograft such quadriceps, patellar, Achilles, hamstring, and anterior and posterior tibialis tendon graft (3-6). Allografts are useful to minimize donor site morbidity but are associated with increased cost, slower incorporation time, increased risk of disease transmission, and a higher failure rate (2). The synthetic grafts are yet to prove themselves and currently the most commonly used graft used for ACL reconstruction are autografts namely hamstring or BPTB graft. With BPTB graft comes with advantages of excellent initial fixation, biomechanical properties, durability, success at long- term follow-up with reduced pivot shift test (7, 8) and disadvantage of few reports suggesting donor site morbidity of patellofemoral osteoarthritis, scar formation with shortening of the patellar tendon, loss of terminal knee extension, and patellofemoral pain(2,9,10).
Semitendinosus and gracilis tendons (quadrupled hamstring tendon [HT]) have found to minimize donor site morbidity causing less anterior pain(8) with disadvantage of numbness of the anterior knee caused by injury to the infrapatellar branch of the saphenous nerve during graft harvest(2), longer rehabilitation period(3,10) and persisting pivot shift test at long term follow up(7). There are multiple extrinsic and intrinsic confounding variables(11) while studying the results of ACL reconstruction out of which isolated effects of a single extrinsic variable of graft choice is to be made.

Method of Review
There are several review articles published in literature including Pubmed, Medline and Cochrane database to compare of graft superiority (hamstring versus BPTB) in ACL reconstruction. We primarily did a pubmed search with Bone-Patellar Tendon-Bone Grafting as the Mesh major keyword. Two hundred and eighty five article were found and reviewed. There were 51 articles that either compared the two grafts or were meta-analysis of such articles. These 51 articles were then further reviewed to construct this review. There were 9 metanalysis among these 51 articles and 3 additional systematic reviews (1,4,7, 11-20). The Cochrane review of 2011 and a systematic summary of systematic reviews was also added to this list (21,22). Results of all these reviews were compiled and presented in Table 1. Other relevant articles were added to the review depending on the significance of their findings. It was noted that in most article the main areas of comparison between the two grafts were stability, donor site morbidity, complications, rehabilitation status, functional outcomes and revision rates due to graft. The present review is also arranged in this format.

Functional outcome
Functional outcome was measured in most of the articles using scores like Lysholm knee score, Tegner activity level, International Knee Documentation Committee (IKDC) scores etc. None of the studies found any difference in functional outcome measured (1,4,7,11-19,23-25) and hence both the grafts are equally effective in terms of restoring the functional ability of the patients. Pinczewski et al noted that Level 1 and 2 sports activities were significantly reduced from 73 to 85% (short term) to 45-57% (long term results) in both HT and BTPB groups (11). Recent review mentions that patients with HT graft are almost twice more likely to return to sports but patient with BPTB Graft are more likely to return or exceed the preoperative sports level (22). Other also indicate that patients with BPTB graft return to activity earlier than the HT graft (12). This may be probably because BPTB graft provide more static and rotational stability (1,15). Poolman et al (17) commented that modern techniques of HT graft will further increase stability and improve return to activity. However this is not confirmed by recent articles and possibly better controlled trials will be needed to eventually answer the question.

Donor site morbidity and complication after graft harvesting
When overall incidence of morbidity was reviewed, HT graft patient have lower incidence of morbidity (12,15). Anterior knee pain and kneeling pain was significant in BTPB group as compared with HT group(1–3,11,23). Anterior knee pain is related to the secondary chondromalacia patella which happens after ACL reconstruction regardless of graft type but it is noted that it can be five times greater in BPTB group versus HT group(2). There was a significant extension loss of >5 degrees in BPTB group versus HT group(1). It is noted that there was a concentric and eccentric reduction in Quadriceps power which was related to poor satisfaction rates (23). The Cochrane review in 2011 noted that BPTB Graft resulted in loss of knee extension range and strength while HT graft showed trend toward loss of flexion range and strength (21). There was a slight risk of patellar fracture which was mainly related to the errors in the surgical technique or use of unnecessary deeper saw cuts or osteotomes(23). Other donor site problems noted are patellar tendinitis, rupture of patellar tendon, increased joint stiffness, late chondromalacia and injury to infrapatellar branch of saphenous nerve(2,3,23). Reduced ultimate range of motion may be related to the rigid construct used in fixing BPTB graft (2). Other disadvantage of hamstring graft are injury to the superficial branch saphenous nerve and weakness of the hamstring muscles after operation (23, 24).

Stability
Stability has shown varied results in different studies and possible is a function of surgical technique and rehabilitation [Table 1].

Table 1: Comparative analysis of meta-analysis comparing BPTB and HT autograft

Table 1: Comparative analysis of meta-analysis comparing BPTB and HT autograft

Stability was assessed by Lachman test, pivot shift test and KT -1000 arthrometer in most series. Some authors reported no significant difference between either HT or BPTB group at long term follow up (11, 2). However, in mid-term follow up the side-to-side instrumented laxity (>2 mm) was greater in HT group as compared to BPTB group (7). BTPB is also found to be more rotationally stable with respect to pivot shift test (1).
Stability in case of HT graft was based on the number of strands used during surgery when compared with BPTB graft (1). When a 2 strand HT graft was used a statistical difference was noted in case of KT – 1000 and pivot shift test in favour of BPTB graft whereas Lachman test was not significant in both groups. If a 4 strand HT graft with a suspensory fixation like endobutton was used then the statistical difference was not significant in both the groups and had near normal Lachman, pivot shift tests and KT – 1000 testing(1,10,26–28). There is a slightly higher degrees of laxity noted in quadrupled hamstring graft as compared with BPTB graft especially in females in long term studies(2,20). Cochrane review noted that BPTB reconstructions are more likely to result in statically stable knees but they are also associated with more anterior knee problems. However there is insufficient evidence to predict superiority of one graft over other in long results in respect to functional outcome(21). In a study, comparing double bundle reconstruction with HT graft and anatomical BPTB graft positioning equal results are found with respect to stability and laxity throughout the range of motion(29). The recent summary of meta-analysis however concluded that BPTB graft are more stable as per the current available evidence (22)

Rehabilitation
It is noted that integration of bone to bone healing with direct insertion is much faster in BPTB graft as compared to bone to soft tissue healing by means of indirect insertions with sharpey’s fibres in case of HT graft(23). So with rapid incorporation with graft healing to bone, there is potential for accelerated rehabilitation in BPTB graft and may be earlier return to play sports activities(3,23). It usually takes 6 weeks for a BPTB to incorporate in the host bone whereas around 8 to 12 weeks with HT graft(3). Short term studies showed mixed results of quadriceps strength with HT graft harvest whereas long term studies shows no difference in quadriceps strength with BPTB versus HT graft(8,20). Evaluation of functional capacities: power, strength, velocity and dynamic stability of knee extensor and flexor muscles after ACL reconstruction showed that use of a BPTB autograft achieved better muscular and functional capacities than the HT autograft(6). During rehabilitation with hamstring graft requires less supervision with less risk of complications such as the infrapatellar contracture syndrome, arthrofibrosis or persisting pain(23).

Osteoarthritis Risk
Radiographic assessment showed no significant differences between the two groups in terms of osteoarthritic findings classified according to the Fairbank and Ahlback rating systems in short term studies(26) and mild osteoarthritic changes in BPTB group at mid and long term follow up as compared with HT group(11). Overall, osteoarthritis was identified in 16% (BPTB 19%; ST 13%.) according to the Ahlback rating system and 68% (BPTB 67%; ST 70%; ) according to the Fairbank rating system(26). Xie et al found the risk of development of OA was around 61% greater in BPTB graft as compared to HT Graft (14). Early osteoarthritic changes are also function of primary injury and associated injuries like meniscal injuries and cartilage injuries (30). However late onset osteoarthritis will require much longer follow up and none of the current studies offer much insight into development of OA in long term (22)

Failure rates
There is no obvious difference in the occurrence of ligament failure between HT group and the BPTB group after ACL reconstruction in long term studies but a few studies demonstrate reduced failure rates with BPTB graft(1). Hamstring graft harvest weakens the knee flexor strength leading to slightly higher degrees of graft failure (2,4). However, these studies had a selection bias which had included studies using double or triple strand graft which gave slightly higher failure rates. Long term studies have shown to have equal success rates with quadrupled hamstring graft or BPTB graft(8,20). Moreover, it is also noted that the fixation modality and anatomical placement of ACL is responsible for low failure rates(20) It has been noted that contralateral ACL tear with BPTB graft is statistically significant as compared to HT graft in short term studies whereas in long term studies there is no increase in contralateral ACL tear(8). A risk factor for contralateral ACL rupture was a return to sports that involved sidestepping, pivoting, and jumping (8). In a registry study based on 45,998 primary ACL Reconstructions in Scandinavi it was found that patients receiving patellar tendon autografts have a statistically significantly lower risk of revision compared with patients receiving hamstring autografts(5).


Conclusions

As per current reviews and evidence, both graft achieve good functional outcome in patients. BPTB graft may offer a more stable knee and possible achieve rapid and effective return to preinjury activity level. HT graft have less donor site morbidity and with new effective fixation modalities, they may also match the stability achieved by BPTB grafts. However there is insufficient evidence to clearly establish a winner and probably more robust future studies will be better able to define the role of each of these autograft options


References

1. Li S, Su W, Zhao J, Xu Y, Bo Z, Ding X, et al. Review A meta-analysis of hamstring autografts versus bone – patellar tendon – bone autografts for reconstruction of the anterior cruciate ligament. Knee 2011;18(5):287–93.
2. Shelton WR, Fagan BC. Autografts Commonly Used in Anterior Cruciate Ligament. J Am Acad Orthop Surg. 2011;19(5):259–64.
3. West R V, Harner CD. Graft Selection in Anterior Cruciate Ligament Reconstruction. J Am Acad Orthop Surg. 2005;13(3):197–207.
4. Reinhardt KR, Hetsroni I. Graft Selection for Anterior Cruciate Ligament Reconstruction : A Level I Systematic Review Comparing Failure Rates and Functional Outcomes. Orthop Clin NA [Internet]. Elsevier Ltd; 2010;41(2):249–62.
5. Gifstad T, Foss OA, Engebretsen L, Lind M, Forssblad M, Albrektsen G. Lower Risk of Revision With Patellar Tendon Autografts Compared With Hamstring Autografts A Registry Study Based on 45 , 998 Primary ACL Reconstructions in Scandinavia. Am J Sports Med. 2014;42(10):2319–28.
6. Baur C, Mathieu N, Delamorclaz S, Hilfiker R, Blatter S, Siegrist O, et al. Anterior cruciate ligament reconstruction : Hamstring Tendon autograft versus Bone Patellar Tendon Bone autograft : what about muscular and functional capacities ? Schweizerische Zeitschrift für Sport und Sport. 2015;63(2):18–22.
7. Biau DJ, Katsahian S, Kartus J, Harilainen A, Feller JA, Sajovic M, et al. Patellar Tendon Versus Hamstring Tendon Autografts for Reconstructing the Anterior Cruciate Ligament : A Meta-Analysis Based on Individual Patient Data. Am J Sports Med. 2009;37(12):2470–8.
8. Macaulay AA, Perfetti DC, Levine WN, Macaulay AA, Perfetti DC, Levine WN. Anterior Cruciate Ligament Graft Choices. Sport Heal A Multidiscip Approach. 2012;4(1).
9. Dahm DL. A Meta-analysis of Patellar Tendon Autograft Versus Patellar Tendon Allograft in Anterior Cruciate Ligament Reconstruction. Arthrosc J Arthrosc Relat Surg. 2008;24(3):292–8.
10. Siebold R, Webster ÆKE, Feller ÆJA, Sutherland AG, Elliott ÆJ. Anterior cruciate ligament reconstruction in females : a comparison of hamstring tendon and patellar tendon autografts. Knee. 2006;14:1070–6.
11. Pinczewski LA, Lyman J, Salmon LJ, Russell VJ, Roe J, Linklater J. A 10-Year Comparison of Anterior Cruciate Ligament Reconstructions With Hamstring Tendon and Patellar Tendon Autograft A Controlled , Prospective Trial. Am J Sports Med. 2007;10(10):1–11.
12. Xie X, Liu X, Chen Z, Yu Y, Peng S, Li Q. A meta-analysis of bone-patellar tendon-bone autograft versus four-strand hamstring tendon autograft for anterior cruciate ligament reconstruction. Knee. 2015 Mar;22(2):100-10
13: Yao LW, Wang Q, Zhang L, Zhang C, Zhang B, Zhang YJ, Feng SQ. Patellar tendon autograft versus patellar tendon allograft in anterior cruciate ligament reconstruction: a systematic review and meta-analysis. Eur J Orthop Surg Traumatol. 2015 Feb;25(2):355-65.
14. Xie X, Xiao Z, Li Q, Zhu B, Chen J, Chen H, Yang F, Chen Y, Lai Q, Liu X. Increased incidence of osteoarthritis of knee joint after ACL reconstruction with bone-patellar tendon-bone autografts than hamstring autografts: a meta-analysis of 1,443 patients at a minimum of 5 years. Eur J Orthop Surg Traumatol. 2015 Jan;25(1):149-59.
15. Li S, Chen Y, Lin Z, Cui W, Zhao J, Su W. A systematic review of randomized controlled clinical trials comparing hamstring autografts versus bone-patellar tendon-bone autografts for the reconstruction of the anterior cruciate ligament. Arch Orthop Trauma Surg. 2012 Sep;132(9):1287-97
16. Biau DJ, Katsahian S, Nizard R. Hamstring tendon autograft better than bone-patellar tendon-bone autograft in ACL reconstruction – a cumulative meta-analysis and clinically relevant sensitivity analysis applied to a previously published analysis. Acta Orthop. 2007 Oct;78(5):705-7
17. Poolman RW, Farrokhyar F, Bhandari M. Hamstring tendon autograft better than bone patellar-tendon bone autograft in ACL reconstruction: a cumulative meta-analysis and clinically relevant sensitivity analysis applied to a previously published analysis. Acta Orthop. 2007 Jun;78(3):350-4.
18. Biau DJ, Tournoux C, Katsahian S, Schranz PJ, Nizard RS. Bone-patellar tendon-bone autografts versus hamstring autografts for reconstruction of anterior cruciate ligament: meta-analysis. BMJ. 2006 Apr 29;332(7548):995-1001.
19. Harilainen A, Linko E, Sandelin J. Randomized prospective study of ACL reconstruction with interference screw fixation in patellar tendon autografts versus femoral metal plate suspension and tibial post fixation in hamstring tendon autografts: 5-year clinical and radiological follow-up results. Knee Surg Sports Traumatol Arthrosc. 2006 Jun;14(6):517-28.
20. Spindler KP, Kuhn JE, Freedman KB, Matthews CE, Dittus RS, Harrell FE Jr. Anterior cruciate ligament reconstruction autograft choice: bone-tendon-bone versus hamstring: does it really matter? A systematic review. Am J Sports Med. 2004 Dec;32(8):1986-95.
21. Mohtadi NG, Chan DS, Dainty KN, Whelan DB. Patellar tendon versus hamstring tendon autograft for anterior cruciate ligament rupture in adults. Cochrane Database Syst Rev. 2011 Sep 7;(9):CD005960.
22. Anderson MJ, Browning WM 3rd, Urband CE, Kluczynski MA, Bisson LJ. A Systematic Summary of Systematic Reviews on the Topic of the Anterior Cruciate Ligament. Orthop J Sports Med. 2016 Mar 15;4(3):2325967116634074.
23. Bartlett RJ, Clatworthy MG, Nguyen TN V. Review article GRAFT SELECTION IN RECONSTRUCTION OF THE ANTERIOR CRUCIATE LIGAMENT. J Bone Joint Surg Br. 2001;83(July):625–34.
24. Matjaz S, Andrej S, Radko K, Mojca D. The effect of graft choice on functional outcome in anterior cruciate ligament reconstruction. Int Orthop. 2008;32:473–8.
25. Martin NJ, Shishir SM, Kanagasabai R, Najimudeen S, Gnanadoss JJ. “ Quadruple hamstring tendon graft versus Bone-Patellar- Tendon-Graft for arthroscopic Anterior Cruciate Ligament reconstruction- comparison study with follow up of 2 years .” IOSR J Dent Med Sci. 2014;13(11):6–13.

26. Ahlde M. Knee laxity measurements after anterior cruciate ligament reconstruction , using either bone – patellar – tendon – bone or hamstring tendon autografts , with special emphasis on comparison over time. Knee. 2009;17:1117–24.
27. Svensson M, Ejerhed L, Kartus T. A prospective comparison of bone-patellar tendon-bone and hamstring grafts for anterior cruciate ligament reconstruction in female patients. Knee Surgery, Sport Traumatol Arthrosc. 2006;14:278–86.
28. Gauti L, Ninni S, Lars E, Jon K, Juri K. A prospective comparison of bone-patellar tendon-bone and hamstring tendon grafts for anterior cruciate ligament reconstruction in male patients. Knee. 2007;15:115–25.
29. Ishibashi Y, Tsuda E, Fukuda A, Tsukada H. Intraoperative Biomechanical Evaluation of Anatomic Anterior Cruciate Ligament Reconstruction Using a Navigation System Comparison of Hamstring Tendon and Bone – Patellar Tendon – Bone Graft. Am J Sports Med. 2008;36(10):1903–12.
30. Andersson D, Samuelsson K, Karlsson J. Treatment of anterior cruciate ligament injuries with special reference to surgical technique and rehabilitation: an assessment of randomized controlled trials. Arthroscopy. 2009 Jun;25(6):653-85


How to Cite this article:. Tapasvi S, Jain S, Shyam AK. BTB Vs Hamsrtings – Is There a Winner Yet ?. Asian Journal of Arthroscopy  Apr-June 2016;1(1):11-15 .

 

Dr. Sachin Tapasvi

Dr. Sachin Tapasvi

Dr. Sachin Jain

Dr. Sachin Jain

Dr. Ashok Shyam

Dr. Ashok Shyam


(Abstract)      (Full Text HTML)      (Download PDF)