Survivorship, complications, and outcomes of custom glenoid implants in reverse total shoulder arthroplasty: a systematic review.

Background: Custom glenoid baseplates have emerged to manage severe glenoid bone loss in reverse total shoulder arthroplasty (rTSA). While early clinical and radiographic results are encouraging, complication and failure rates remain poorly characterized. This systematic review aimed to evaluate the survivorship, complications, and clinical outcomes of custom glenoid implants used in rTSA. Methods: A comprehensive literature search of Cochrane, Embase, and MEDLINE databases was performed to identify studies using custom glenoid baseplates in rTSA. Inclusion criteria encompassed clinical studies reporting complication rates, failure etiology, and functional outcomes. Data extraction included demographics, follow-up duration, failures, complication rates, patient-reported outcome measures (PROMs), and range of motion. Weighted means and standard deviations were calculated using pooled data. Results: Nine studies encompassing 168 shoulders (63 primary and 105 revision rTSAs) met inclusion criteria. The weighted mean age was 69.7 years with an average follow-up of 31.6 months. The overall failure rate was 3.3%, with glenoid loosening accounting for only 0.6% of cases. The most common failure mechanism was humeral component loosening. The overall complication rate was 30.9%, higher in revision cases (27.8%) than primary (12.9%). There were improvements in PROMs such as the Constant-Murley Score, American Shoulder and Elbow Surgeons score, Disability of the Arm, Shoulder, and Hand score, Simple Shoulder Test, Single Assessment Numeric Evaluatio, and Visual Analog Score scores. Similarly, patients experienced meaningful gains in active forward flexion (+48.3°-+61.4°), abduction (+33.6°-+34.5°), and external rotation (+11.0°-+24.1°), with superior improvements in primary compared to revision procedures. Discussion and Conclusion: At short term follow-up, custom glenoid components failure rate remained low, with improvements exceeding minimal clinical important differences in PROMs and marked improvement in range of motion. The glenoid loosening rate was 0.6% in patients undergoing rTSA with a custom glenoid component at a weighted average follow-up of 31.6 ± 6.7 months.