Benefits of a metallic lateralized baseplate prolonged by a long metallic post in reverse shoulder arthroplasty to address glenoid bone loss.

Abstract

Severe glenoid bone loss remains a surgical challenge. This condition is known to be associated with high rates of glenoid component failure. The objective of this study was to evaluate clinical and radiological outcomes of a lateralized metal-backed 15.2-mm keeled baseplate prolonged by a thin 24.8-mm metallic post fixed directly in the subscapularis fossa in primary cases of reverse shoulder arthroplasty (RSA) for severe glenoid bone loss and in revision cases. Between January 2011 and December 2014, 51 shoulders (50 patients) underwent primary or revision RSA using this baseplate. Forty-five shoulders in 44 patients were followed for a minimum of twoyears (mean, 33months; range, 24-60months). The mean age of the patients was 76years (range, 55-93years). Outcome measures included pain, range of motion, Constant Score, and complications. The complication rate was 12% in primary cases and 25% in revision cases. One glenoid implant (4%) failed in primary cases and one glenoid implant (5%) failed in revision cases. Pain and range of motion were significantly improved in both groups. The mean Constant Score improved from 24 (± 7) to 62 (± 9) in primary cases and from 24 (± 10) to 58 (± 12) in revision cases. A lateralized metal-backed 15.2-mm keeled baseplate prolonged by a thin 24.8-mm metallic post fixed directly in the subscapularis fossa may provide satisfactory mid-term outcomes in patients with large glenoid bone defects where initial press-fit of a regular baseplate is impossible to obtain.