RESUMO
BACKGROUND: Most anatomic total shoulder arthroplasty (ATSA) techniques release and reattach the subscapularis tendon. The risk of failed healing is a widely recognized complication. The purpose of this study was to radiographically compare a traditional deltopectoral (DP) approach and a superolateral subscapularis sparing (SSS) technique through the rotator interval. METHODS: A single, independent, blinded, reviewer analyzed preoperative and postoperative radiographs of patients undergoing ATSA performed by a single surgeon. The reviewer assessed humeral head height, humeral head medial offset, humeral head diameter, head-neck angle, humeral head centering, and coracohumeral offset, and used the anatomic reconstruction index (ARI) to evaluate overall reconstruction quality. RESULTS: There were 70 SSS and 20 DP patients included. When comparing preoperative with postoperative differences, we found that there was no difference between groups in humeral head height (P = .19), humeral head medial offset (P = .38), and coracohumeral offset (P = .07). The DP group had a mean humeral head diameter oversizing of 1.4 mm, whereas the superolateral group had an undersizing of 2.8 mm (P < .001). The head-neck angle difference of the SSS approach was 2° greater than that found with the DP group (P < .001). The humeral head centering in the DP group was 7% displaced vs. 12% with the SSS group (P = .001) relative to the glenoid size. The ARI was 7.35 for the DP group and 6.93 for the SSS group (P = .50). DISCUSSION AND CONCLUSIONS: Radiographic comparison of these 2 ATSA techniques identified no statistical significant difference in 4 of 7 radiographic measurements and ARI. The SSS ATSA is a reasonable approach that yields similar radiographic measurements as a traditional DP total shoulder arthroplasty approach.
