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

Abstract

Background: Severe glenoid bone loss remains a surgical challenge. This condition is known to be associated with high rates of glenoid component failure. Purpose: 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. Materials and methods: 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 two years (mean, 33 months; range, 24–60 months). The mean age of the patients was 76 years (range, 55–93 years). Outcome measures included pain, range of motion, Constant Score, and complications. Results: 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. Conclusion: 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.