Mehmet CETİNKAYAA, Muhammet Baybars ATAOGLUB, Mustafa OZERC, Tacettin AYANOGLUD, Ali Yusuf ONERE, Ulunay KANATLI

Do subscapularis tears really result in superior humeral migration?

Objectives: The aim of this study was to analyse the effect of subscapularis tear on superior humeralexcursion (SHE) and acromiohumeral distance (AHD). The hypothesis was that subscapularis tears do notresult in superior humeral excursion.Methods: Patients who underwent shoulder arthroscopy between August of 2011 and 2015 werereevaluated. Those with isolated Bankart lesion were used as control group and included in the Group 1,isolated full-thickness supraspinatus tear in the Group 2, isolated subscapularis tear in the Group 3, andcombined subscapularis and supraspinatus tear in the Group 4. The mean SHE and AHD measurementson magnetic resonance imaging of these groups were compared to reveal any difference in superiorhumeral migration (SHM).Results: There were 30 patients in each group. The mean age of Group 1 (26.44± 8.34) was younger thanthe other 3 groups. The mean AHD and SHE were higher in Group 1 and 3 (Mean AHD: 12.89± 2.24 and12.28± 1.9, respectively. Mean SHE: 3.2 ± 0.99 and 2.78 ± 0.64, respectively) than Group 2 and 4(Mean AHD: 6.2± 1.78 and 6.16 ± 1.52, respectively. Mean SHE: 0.72 ± 0.65 and 1.24 ± 0.63, respectively).The AHD and SHE were strongly correlated with each other (Pearson correlation coefŞcient ¼ 0.184). Theinter-observer and intra-observer correlation of the measurements of SHE on MRI were excellent withintraclass correlation coefŞcient of 0.95 and 0.94, respectively.Conclusion: Subscapularis tears do not lead to SHM and subacromial impingement. However, superior rotator cuff tears can still lead to SHM and subacromial impingement even when subscapularis tendon is intact.Level of evidence: Level III, diagnostic study.

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1. Golding FC. The shoulderethe forgotten joint. Br J Radiol. 1962;35:149e158.

2. Weiner DS, Macnab I. Superior migration of the humeral head. A radiological aid in the diagnosis of tears of the rotator cuff. J Bone Joint Surg Br. 1970;52: 524e527.

3. Burkhart SS. Arthroscopic treatment of massive rotator cuff tears. Clinical results and biomechanical rationale. Clin Orthop Relat Res. 1991;267:45e56.

4. Lippitt S, Matsen F. Mechanisms of glenohumeral joint stability. Clin Orthop Relat Res. 1993;291:20e28.

5. Inman VT, Saunders JB, Abbott LC. Observations of the function of the shoulder joint. Clin Orthop Relat Res. 1996;330:3e12.

6. Sharkey NA, Marder RA. The rotator cuff opposes superior translation of the humeral head. Am J Sports Med. 1995;23:270e275.

7. Halder AM, Zhao KD, Odriscoll SW, Morrey BF, An KN. Dynamic contributions to superior shoulder stability. J Orthop Res. 2001;19:206e212.

8. Bezer M, Yildirim Y, Akgun U, Erol B, Guven O. Superior excursion of the humeral head: a diagnostic tool in rotator cuff tear surgery. J Shoulder Elbow Surg. 2005;14:375e379.

9. Lafosse L, Jost B, Reiland Y, Audebert S, Toussaint B, Gobezie R. Structural integrity and clinical outcomes after arthroscopic repair of isolated subscapularis tears. J Bone Joint Surg Am. 2007;89:1184e1193.

10. Sharma G, Bhandary S, Khandige G, Kabra U. MR imaging of rotator cuff tears: correlation with arthroscopy. J Clin Diagn Res. 2017;11:TC24eTC27.

11. Gyftopoulos S, OD J, Shah NP, Goss J, Babb J, Recht MP. Correlation of MRI with arthroscopy for the evaluation of the subscapularis tendon: a musculoskeletal division's experience. Skeletal Radiol. 2013;42:1269e1275.

12. Poppen NK, Walker PS. Normal and abnormal motion of the shoulder. J Bone Joint Surg Am. 1976;58:195e201.

13. Keener JD, Wei AS, Kim HM, Steger-May K, Yamaguchi K. Proximal humeral migration in shoulders with symptomatic and asymptomatic rotator cuff tears. J Bone Joint Surg Am. 2009;91:1405e1413.

14. Leschinger T, Wallraff C, Muller D, Hackenbroch M, Bovenschulte H, Siewe J. In vivo analysis of coracoid and subacromial shoulder impingement mechanism during clinical examination. Eur J Orthop Surg Traumatol. 2017;27:367e372.

15. Saupe N, Pfirrmann CW, Schmid MR, Jost B, Werner CM, Zanetti M. Association between rotator cuff abnormalities and reduced acromiohumeral distance. AJR Am J Roentgenol. 2006;187:376e382.

16. Mura N, O'Driscoll SW, Zobitz ME, et al. The effect of infraspinatus disruption on glenohumeral torque and superior migration of the humeral head: a biomechanical study. J Shoulder Elbow Surg. 2003;12:179e184.

17. Royer PJ, Kane EJ, Parks KE, et al. Fluoroscopic assessment of rotator cuff fatigue on glenohumeral arthrokinematics in shoulder impingement syndrome. J Shoulder Elbow Surg. 2009;18:968e975.

18. Steenbrink F, de Groot JH, Veeger HE, van der Helm FC, Rozing PM. Glenohumeral stability in simulated rotator cuff tears. J Biomech. 2009;42:1740e1745.

19. Neer 2nd CS. Anterior acromioplasty for the chronic impingement syndrome in the shoulder: a preliminary report. J Bone Joint Surg Am. 1972;54:41e50.

20. Escamilla RF, Yamashiro K, Paulos L, Andrews JR. Shoulder muscle activity and function in common shoulder rehabilitation exercises. Sports Med. 2009;39: 663e685.

21. Graichen H, Stammberger T, Bonel H, Karl-Hans E, Reiser M, Eckstein F. Glenohumeral translation during active and passive elevation of the shoulder - a 3D open-MRI study. J Biomech. 2000;33:609e613.

22. Chopp JN, O'Neill JM, Hurley K, Dickerson CR. Superior humeral head migration occurs after a protocol designed to fatigue the rotator cuff: a radiographic analysis. J Shoulder Elbow Surg. 2010;19:1137e1144.

23. Teyhen DS, Christ TR, Ballas ER, et al. Digital fluoroscopic video assessment of glenohumeral migration: static vs. Dynamic conditions. J Biomech. 2010;43: 1380e1385.

24. Chopp JN, Dickerson CR. Resolving the contributions of fatigue-induced migration and scapular reorientation on the subacromial space: an orthopaedic geometric simulation analysis. Hum Mov Sci. 2012;31:448e460.

25. Millett PJ, Giphart JE, Wilson KJ, Kagnes K, Greenspoon JA. Alterations in glenohumeral kinematics in patients with rotator cuff tears measured with Biplane fluoroscopy. Arthroscopy. 2016;32:446e451.

26. Buss DD, Freehill MQ, Marra G. Typical and atypical shoulder impingement syndrome: diagnosis, treatment, and pitfalls. Instr Course Lect. 2009;58:447e457.

27. Deutsch A, Altchek DW, Schwartz E, Otis JC, Warren RF. Radiologic measurement of superior displacement of the humeral head in the impingement syndrome. J Shoulder Elbow Surg. 1996;5:186e193.

28. Nishinaka N, Tsutsui H, Mihara K, et al. Determination of in vivo glenohumeral translation using fluoroscopy and shape-matching techniques. J Shoulder Elbow Surg. 2008;17:319e322.

29. Flury MP, John M, Goldhahn J, Schwyzer HK, Simmen BR. Rupture of the subscapularis tendon (isolated or in combination with supraspinatus tear): when is a repair indicated? J Shoulder Elbow Surg. 2006;15:659e664.

30. Heikenfeld R, Gigis I, Chytas A, Listringhaus R, Godolias G. Arthroscopic reconstruction of isolated subscapularis tears: clinical results and structural integrity after 24 months. Arthroscopy. 2012;28:1805e1811.

31. van der Zwaal P, Schuller L, Urlings TA, Coerkamp EG, van Arkel ER, van der List MP. Clinical outcome and structural integrity of all-arthroscopic repair of degenerative subscapularis tendon tears. Knee Surg Sports Traumatol Arthrosc. 2013;21:1620e1625.

32. Maqdes A, Abarca J, Moraiti C, et al. Does preoperative subscapularis fatty muscle infiltration really matter in anterosuperior rotator cuff tears repair outcomes? A prospective multicentric study. Orthop Traumatol Surg Res. 2014;100:485e488.