Does reverse total shoulder arthroplasty with allograft-prosthesis composite (APC) have surgical benefits over hemiarthroplasty with APC in patients with tumors of the proximal humerus?

BACKGROUNDThe research on surgical outcomes of hemiarthroplasty and reverse total shoulder arthroplasty using allograft-prosthesis composites for the proximal humeral oncologic condition is still scarce. Therefore, this study aimed to compare surgical outcomes of shoulder joint reconstruction with hemiarthroplasty and reverse total shoulder arthroplasty using allograft-prosthesis composites for tumors of the proximal humerus. METHODSEleven patients underwent hemiarthroplasty or reverse total shoulder arthroplasty using allograft-prosthesis composites for tumors of the proximal humerus between July 2011 and April 2018 were reviewed. Radiographic analysis for bone union of allograft-host bone junction, implant loosening, stress shielding and shoulder dislocation or subluxation was performed. Functional outcomes were evaluated using visual analog scales for pain, range of motion, Simple Shoulder Test score and Musculoskeletal Tumor Society score. Furthermore, oncologic outcome and complications were also assessed, respectively. RESULTSThere were five patients with hemiarthroplasty (mean age, 23.2 years) and six patients with reverse total shoulder arthroplasty (mean age, 46.8 years, P = 0.05). Radiographically, there were no events associated with implant loosening, stress shielding and shoulder dislocation or subluxation in the two groups. There were no differences in functional outcomes between the two groups. There was no local recurrence in entire cohort. In the hemiarthroplasty group, one patient was required revision surgery to reverse total shoulder arthroplasty at postoperative 6 years due to rotator cuff dysfunction. In the reverse total shoulder arthroplasty group, one patient showed the fracture occurred at allograft-host bone junction at postoperative 6 months. CONCLUSIONSSurgical outcomes of hemiarthroplasty with allograft-prosthesis composites were not inferior to reverse total shoulder arthroplasty when applied in properly selected patients. The authors recommended that hemiarthroplasty with allograft-prosthesis composites could be used for young age patients without glenoid metastasis involvement, and reverse total shoulder arthroplasty with allograft-prosthesis composites could be used for patients with old age or metastatic bone tumors.