Stemless anatomic total shoulder arthroplasty: a systematic review and meta-analysis
These authors conducted a review of 22 studies on stemless anatomic total shoulder arthroplasty (TSA) is used in the treatment of osteoarthritis
Meta-analysis of comparative studies between stemless and stemmed TSA identified no significant differences in postoperative Constant scores or complication rates. Stemless TSA had shorter operative time and decreased intraoperative blood loss.
Eleven of the studies reported intraoperative revisions to stemmed implants because of insufficient fixation. They point out that there is currently no objective way to asses at the time of surgery whether the metapyseal bone quality is adequate to support a stemless implant.
Of the patients, 7.8% had glenoid radiolucent lines (RLLs), 18.4% had humeral RLLs, and 8.3% had periprosthetic RLLs not further specified. Furthermore, 1.8% had humeral head displacement and/or migration, and 2.1% had humeral osteolysis. No cases of postoperative humeral loosening were reported.
Comment: In this analysis, the clinical outomes and revision rates were not better for the stemless implants in comparison to standard stemmed implants. In contrast to the use of stemmed implants, the use of stemless implants requires the surgeon to assess metaphyseal bone quality and to accept the risk of needing to convert to a stemmed implant intraoperatively if fixation is inadequate.
The retention of the metaphysis may compromise glenoid exposure 
Use of a stemless implant requires attention to avoid errors in positioning
