Revision to reverse shoulder arthroplasty with retention of the humeral component: Good outcome in 14 patients followed for a mean of 2.5 years

BACKGROUND: Revision in failed shoulder arthroplasty often requires removal of the humeral component with a significant risk of fracture and bone loss. Newer modular systems allow conversion from anatomic to reverse shoulder arthroplasty with retention of a well-fixed humeral stem. We report on a prospectively evaluated series of conversions from hemiarthroplasty to reverse shoulder arthroplasty. METHODS: In 14 cases of failed hemiarthroplasty due to rotator cuff deficiency and painful pseudoparalysis (in 13 women), revision to reverse shoulder arthroplasty was performed between October 2006 and 2010, with retention of the humeral component using modular systems. Mean age at the time of operation was 70 (56–80) years. Pre- and postoperative evaluation followed a standardized protocol including Constant score, range of motion, and radiographic analysis. Mean follow-up time was 2.5 (2–5.5) years. RESULTS: Mean Constant score improved from 9 (2–16) to 41 (17–74) points. Mean lengthening of the arm was 2.6 (0.9–4.7) cm without any neurological complications. One patient required revision due to infection. INTERPRETATION: Modular systems allow retainment of a well-fixed humeral stem with good outcome. There is a risk of excessive humeral lengthening.