Background: Among the uncommon and frequently missed orthopedics injuries is the posterior shoulder dislocation, accounting for about 2-4 % of all shoulder dislocations. Commonly, it is associated with the well-known reverse Hill-Sachs lesion. Several surgical treatment modalities such as transfer of subscapularis tendon or lesser tuberosity, humeral rotational osteotomy, osteochondral grafts were used to repair this defect. Hemiarthroplasty or total shoulder arthroplasty was used as salvage procedure in non-constructable defect or neglected old dislocation.
Patients and methods: This study included 11 patients with locked chronic posterior shoulder dislocation and reverse Hill-Sachs defects falling in the target range (25-50 % of the head size). The mean age of the patients was 39 (range 31-49) years. Mean time from injury to surgery was 9 (range 3-18) weeks. Open reduction in the dislocated head with the transfer of subscapularis tendon and the attached lesser tuberosity was done to reconstruct the reverse Hill-Sachs defect. The transferred tuberosity was fixed with size 5 Ethibond sutures.
Results: The mean follow-up period was 29 (range 24-39) months. The median of the scores was much improved, reaching 30 (range 20-34) (satisfactory) compared with preoperative median of 24 (range 20-25) (unsatisfactory). This was statistically highly significant (P = 0.002). Postoperatively, 9 patients had no pain or restricted daily living activities. No patient had symptoms of shoulder instability. According to the modified UCLA shoulder rating scale, there were 4 patients rated excellent, 5 patients rated good, one patient rated fair and one patient rated poor.
Conclusion: Reconstructing the reverse Hill-Sachs defect provides adequate stability, pain relief and function in patients with locked chronic posterior shoulder dislocation and a defect involving 25-50 % of the humeral head. The used technique is simple and cost effective with no need for subsequent hardware removal.
Level of evidence: II.
Keywords: Locked chronic posterior shoulder dislocation; Reconstruction; Reverse Hill–Sachs lesion.