Background: To evaluate clinical and radiological outcomes of bony increased offset-reverse total shoulder arthroplasty (BIO-RSA) in the Asian population at mid-term follow-up.Methods: From June 2012 to August 2017 at a single center, 43 patients underwent BIO-RSA, and 38 patients with a minimum of 2 years of follow-up were enrolled. We evaluated the preoperative and postoperative clinical outcomes, radiological outcomes (notching and loosening), and complications of BIO-RSA at the last follow-up. In addition, we divided these patients into notching and not-notching groups and compared the demographics, preoperative, and postoperative characteristics of patients between the two groups.Results: Visual analog scale, American Shoulder and Elbow Surgeons, University of California-Los Angeles, and Simple Shoulder Test scores improved significantly from preoperative (average: 5, 39.43, 16.22, 3.94) to postoperative (average: 1.71, 78.91, 28.34, 7.8; p<0.05) outcomes. All range of motion except internal rotation improved significantly at the final follow-up (p<0.05), and the bone graft was well-incorporated with the native glenoid in all patients (100%). However, scapular notching was observed in 20/38 patients (53%). In the comparison between notching and not-notching groups (18 vs. 20 patients), there were no significant differences in demographics, radiological parameters, and clinical outcomes except acromion-greater tuberosity (AT) distance (p=0.003). Intraoperative complications were three metaphyseal fractures and one inferior screw malposition. Postoperative complications included one heterotopic ossification, one scapula neck stress fracture, one humeral stem loosening, and one late infection.Conclusions: BIO-RSA resulted in improved clinical outcomes at mid-term follow-up in the Asian population. Although better cosmesis and advantages of glenoid lateralization were observed, we observed higher rates of scapular notching compared to previously reported rates in BIO-RSA studies. In addition, adequate glenoid lateralization with appropriate humeral lengthening (AT distance) might reduce scapular notching.
Mid-term outcomes of bony increased offset-reverse total shoulder arthroplasty in the Asian population
