Volume 6 | Issue 1 | January-June 2021 | Page 08-10 | Sharat Balemane, Kaushik Eswaran, Nishanth Shetty
Author: Sharat Balemane , Kaushik Eswaran , Nishanth Shetty 
 Department of Orthopaedics, Yenepoya Medical College,
Address of Correspondence:
Dr. Kaushik Eswaran,
Yenepoya Medical College, Mangalore, India.
Background: The etiopathogenesis of rotator cuff tears remains debatable. Among the many causes, abnormal scapular morphology has been found to accelerate the degenerative process of rotator cuff tears. The morphology and lateral extension of the acromion process were assessed indetail by Nyffeler et al. and the Acromion Index (AI) was introduced, which measures the lateral extension of the acromion. It was theorized that a large lateral extension of the acromion increased the chances of the supraspinatus tendon to degenerate because of impingement between the acromion and the deltoid muscle. The AI was compared between patients with rotator cuff tears and patients with an intact rotator cuff.
Methods: 21 Indian patients presenting to the orthopaedics OPD, Yenepoya Medical College, with rotator cuff tears were taken up for this study between August 2020 and February 2021. Another 21 patients with intact rotator cuff and other shoulder diseases such as frozen shoulder were included in this study. Patients with rotator cuff tears were included in group A, and patients with intact rotator cuff were included in group B. Both groups had the AI measured on radiographs, and their values were compared.
Results: The mean Acromial Index (AI) in the rotator cuff tear group was 0.74 and in the intact rotator cuff group it was 0.59, which was statistically significant. There was no statistical difference in AI between male and female patients. The mean age of the patients in the rotator cuff group was 50.8 years, and in non rotator cuff tear group, it was 50.2 years.
Conclusion: Acromial Index is a useful predictive tool for detecting rotator cuff tears in the Indian population. Further studies are required to assess its usefulness in predicting the progression of a rotator cuff tear.
Keywords: Rotator cuff tear; Acromial Index; Shoulder.
1. Neer CS., 2nd Impingement lesions. Clin Orthop Relat Res. 1983;(173):70–77.
2. Codman EA. The shoulder: rupture of the supraspinatus tendon and other lesions in or about the subacromial bursa. Boston, MA: Thomas Todd; 1934.
3. Bigliani LU, Morrison DS, April EW. The morphology of the acromion and its relationship to rotator cuff tears. Orthop Trans. 1986;10:228.
4. Aoki M, Ishii S, Usui M. The slope of the acromion and rotator cuff impingement. Orthop Trans. 1986;10:228.
5. Banas MP, Miller RJ, Totterman S. Relationship between the lateral acromion angle and rotator cuff disease. J Should Elbow Surg. 1995;4(6):454–461. doi: 10.1016/S1058-2746(05)80038-2.
6. Nyffeler RW, Werner CM, Sukthankar A, Schmid MR, Gerber C. Association of a large lateral extension of the acromion with rotator cuff tears. J Bone Joint Surg Am. 2006;88(4):800–805. doi: 10.2106/JBJS.D.03042.
7. Miyazaki AN, Itoi E, Sano H, et al. Comparison between the acromion index and rotator cuff tears in the Brazilian and Japanese populations. J Shoulder Elbow Surg. 2011;20(7):1082–1086.
8. Kim JR, Ryu KJ, Hong IT, Kim BK, Kim JH. Can a high acromion index predict rotator cuff tears? Int Orthop. 2012;36(5):1019–1024.
9. Moor BK, Wieser K, Slankamenac K, Gerber C, Bouaicha S. Relationship of individual scapular anatomy and degenerative rotator cuff tears. J Shoulder Elbow Surg. 2014;23(4):536–541.
10. Torrens C, Lopez JM, Puente I, Caceres E. The influence of the acromial coverage index in rotator cuff tears. J Shoulder Elbow Surg. 2007;16(3):347–351.
11. Zumstein MA, Jost B, Hempel J, Hodler J, Gerber C. The clinical and structural long-term results of open repair of massive tears of the rotator cuff. J Bone Joint Surg Am. 2008;90(11):2423–2431.
12. Moor BK, Wieser K, Slankamenac K, Gerber C, Bouaicha S. Relationship of individual scapular anatomy and degenerative rotator cuff tears. J Shoulder Elbow Surg. 2014;23(4):536–541.
13. Balke M, Liem D, Greshake O, Hoeher J, Bouillon B, Banerjee M. Differences in acromial morphology of shoulders in patients with degenerative and traumatic supraspinatus tendon tears. Knee Surg Sports Traumatol Arthrosc. 2016;24(7):2200–2205.
|How to Cite this article: Balemane S, Eswaran K, Shetty N | Acromial Index in Indian Population and its
Significance on Rotator Cuff Tears | Asian Journal of Arthroscopy | January- June
2021; 6(1): 08-10.