Despite the good outcomes with shoulder resurfacing procedures reported by some authors, our team has documented several failures caused by glenoid erosion and rotator cuff rupture, likely due to implant overstuffing. The aim of this study was to evaluate the clinical and radiological outcomes of reverse shoulder arthroplasty (RSA) performed after failed humeral head resurfacing (HHR).
This was a retrospective, single-center study of 17 patients who underwent RSA after failed HHR between January 2011 and February 2016. The mean patient age was 69.4 years and the mean time between HHR and surgical revision was 41 months (14.7-73.5±18.8). Preoperative ultrasonography and CT were used to evaluate the condition of the rotator cuff, extent of glenoid erosion and to look for signs of humeral cup loosening. The clinical outcomes were evaluated pre- and postoperatively using the simple shoulder test (SST), DASH (Disabilities of the Arm, Shoulder and Hand) and the Constant-Murley score. Pain was estimated using a visual analog scale (VAS). The range of motion (ROM) was determined pre- and postoperatively. All patients had standard AP and lateral X-ray views of the shoulder taken as part of their postoperative follow-up protocol to look for implant loosening.
The mean follow-up was 35.9 months (24-59±10.7). There were no intraoperative or postoperative complications. All the functional scores were improved after RSA. The median weighted Constant score preoperatively was 46% (36; 62) while it was 92% postoperatively (78; 100) (p<0.0001). The active ROM improved by 65° in forward flexion (p=0.0003) and by 30° in external rotation (p=0.002). On X-rays, we identified one patient with Sirveaux stage 4 glenoid notching and one patient with a humeral periprosthetic radiolucent line less than 2mm thick in zone 6, with no clinical consequences.
The excellent outcomes after RSA for failed HHR in our study are similar to the ones reported when RSA is performed for cuff tear arthropathy.