Mid-term outcomes of bony increased offset-reverse total shoulder arthroplasty in the Asian population

ABSTRACT

Background@#To evaluate clinical and radiological outcomes of bony increased offset-reverse total shoulder arthroplasty (BIO-RSA) in theAsian 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 minimum 2 years follow-up were enrolled. We evaluated the clinical and radiological outcomes, and complications at the last follow-up. In addition, we dividedthese patients into notching and no-notching groups and compared the demographics, preoperative, and postoperative characteristics ofpatients. @*Results@#Visual analogue scale, American Shoulder and Elbow Surgeons, University of California-Los Angeles Shoulder Scale, and SimpleShoulder Test scores improved significantly from preoperative (5.00, 3.93, 1.72, 3.94) to postoperative (1.72, 78.91, 28.34, 7.66) (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 waswell-incorporated with the native glenoid in all patients (100%). However, scapular notching was observed in 20 of 38 patients (53%). In thecomparison between notching and no-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 included three metaphyseal fractures and one inferior screw malposition. Postoperative complications included ectopic ossification, scapular neckstress fracture, humeral stem relaxation, and late infection in one case each. @*Conclusions@#BIO-RSA showed improved clinical outcomes at mid-term follow-up in Asian population. However, we observed higherscapular notching compared to the previous studies. In addition, adequate glenoid lateralization with appropriate humeral lengthening (ATdistance) might reduce scapular notching.