Allograft reconstruction for humeral head defects in the setting of shoulder instability: a systematic review

BACKGROUND: Glenohumeral joint instability and dislocation are common orthopedic pathologies that can produce osseous humeral head defects such as Hill-Sachs (HS) or Reverse Hill-Sachs (RHS) lesions. Numerous reconstruction techniques have been reported in the literature, including remplissage, disimpaction, and allograft reconstruction. No group has previously assessed the outcomes of allograft reconstruction for RHS lesions, nor compared the outcomes of allograft reconstruction for HS and RHS lesions. In this study, we aim to provide a comprehensive assessment of osteochondral allograft reconstruction for the distinct pathologies of RHS lesions and HS lesions by comparing postreconstruction patient-reported outcomes, complications, and radiographic assessments for each lesion. METHODS: Using Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a systematic review was performed to identify and include studies that reported patient outcomes after the use of osteochondral allografts in the reconstruction of HS or RHS lesions of the humeral head. A comprehensive search of the Google Scholar, PubMed, and Embase databases was conducted with the key terms “allograft,” “Hill-Sachs,” and “reverse Hill-Sachs.” RESULTS: Eight studies, with a total of 84 patients, were included for review. Of the 84 allograft-treated patients, there were 44 patients with HS lesions and 40 patients with RHS lesions. The average patient age was 27.3 years for HS lesions and 43.0 years for RHS lesions. Postoperative range of motion and average Constant-Murley score (87.9 for HS and 80.1 for RHS) appeared to be greater for those with HS lesions. In addition, 20.5% of HS patients experienced postoperative complications, whereas 42.5% of RHS patients had postoperative complications (P = .03). HS and RHS patients experienced similar proportions of graft resorption or collapse rate (22.7% for HS and 12.5% for RHS; P = .2). CONCLUSION: Patient-reported outcomes indicate that osteochondral allograft reconstruction for large RHS and HS lesions is an acceptable intervention. RHS patients had lower rates of graft resorption and collapse but worse postoperative range of motion and functional outcomes, although these differences were not statistically significant. HS patients experienced significantly fewer complications than those with RHS lesions.