Abstract
Introduction & Background
Clinical outcome after reverse total shoulder arthroplasty (RTSA) can be influenced by technical and implant-related factors, so the purpose of this study was to investigate whether individualizing humeral retroversion and subscapularis repair affect the clinical outcomes after RTSA.
Material & Method
Authors retrospectively analyzed the prospectively collected data from 80 patients who underwent RTSA from January 2007 to January 2015 using same implant (Biomet Comprehensive® Reverse Shoulder System, Warsaw, Indiana). The mean follow up was 23.3 ± 1.7 (range, 12 ∼ 70) months. The retroversion of humeral component was decided according to native version estimated using shoulder CT in Group I (n=52), and fixed in 20° retroversion in Group II (n=28). Group I was subdivided into Group Ia (n=21, mean 19.3°), less than 20° of retroversion, and Group Ib (n=31, mean 31.9°), more than 20°. Intraoperative tenotomized subscapularis was repaired in 40 patients in Group I, and could not be repaired due to massive tear including subscapularis in remaining 12 patients. Clinical outcomes were evaluated with range of motion (ROM) and several clinical outcome scores.
Results
Group I showed significantly better ROM and clinical scores compared to Group II at the final follow up (all p < 0.05). There were no significant differences in ROM and clinical scores between Group Ia and Ib. Group Ia showed better ROM and pain VAS than Group II (all p < 0.05), and Group Ib also demonstrated significantly better ROM and clinical outcome scores than Group II (all p < 0.05). With respect to subscapularis repair, there were no differences in ROM and clinical scores between two groups. No complications such as infection or dislocation were detected according to subscapularis repair.
Conclusion
Individualizing humeral retroversion can obtain superior clinical outcomes than fixed 20° retroversion. Subscapularis repair would not be essential for the better clinical outcome in patients with the lateralized RTSA.
