Which Factors Influence Clinical Outcomes After Superior Capsular Reconstruction Surgery?

BACKGROUND: Arthroscopic superior capsular reconstruction (ASCR) has recently been introduced as an alternative treatment for patients with massive irreparable rotator cuff tears. However, the results of ASCR are still limited, and little information about retear after ASCR or subsequent treatment has been reported. PURPOSE: To investigate the retear rate of patients who underwent ASCR and to analyze the clinical outcomes of treatments performed for a retear. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: This was a retrospective analysis of prospectively collected data from 42 patients (46 shoulders) who underwent ASCR between March 2015 and April 2018. All patients were divided into 2 groups: those with no retear (30 shoulders) and those with retear (16 shoulders). Pre- and postoperative clinical and radiological results were compared between the 2 groups. The retear pattern and treatment outcomes of the retear group were analyzed. RESULTS: The overall incidence of retear was 35% (16/46). No difference was found in preoperative demographic or clinical data between the 2 groups. Preoperative magnetic resonance imaging data showed a significant between-group difference in the preoperative Goutallier grade of the subscapularis (1.5 ± 1.1 in the no-retear group vs 2.5 ± 1.3 in the retear group; P = .016). In the retear group, there were 10 cases of lateral side tears, 3 cases of midsubstance tears, 2 cases of medial side tears, and 1 case of medial and lateral tears. Reoperation was performed in 8 patients who had lateral insertion tear. CONCLUSION: Overall, clinical scores improved after ASCR in patients with massive irreparable rotator cuff tears. However, 35% (16/46) of the patients showed retear, and lateral side retear occurred in 68% (11/16). The clinical outcome of the patients with preoperative subscapularis atrophy or postoperative lateral side retears was worse, and reoperation was often required. Therefore, it is important that the lateral side be firmly fixed during the ASCR procedure.