Arthroscopic-assisted lower trapezius transfer vs. superior capsular reconstruction for treatment of massive irreparable rotator cuff tears.

BACKGROUND

Superior capsular reconstruction (SCR) and arthroscopic-assisted lower trapezius transfer (aLTT) are utilized to augment partial rotator cuff repairs (RCRs) in the treatment of massive irreparable rotator cuff tears (MIRCTs), but indications are poorly characterized. SCR restores coronal glenohumeral stability through static reconstruction of the native superior capsule, while aLTT provides dynamic restoration of the posterosuperior aspect of the axial force couple by replicating infraspinatus function. This study compares outcomes between patients undergoing SCR and aLTT with partial RCR for MIRCT to better elucidate indications for each.

METHODS

A retrospective review of our institution's electronic medical record from 2015 to 2022 was conducted. Patients who underwent SCR or aLTT in conjunction with partial RCR for MIRCT and had at least 12 months of follow-up were included. Failure rates, reoperation rates, final range of motion (ROM), and patient-reported outcomes were compared between groups. Outcomes were further stratified by Goutallier classification of supraspinatus and infraspinatus fatty infiltration.

RESULTS

Eighty-one patients were included: 45 underwent aLTT, and 36 underwent SCR. The average follow-up was 33 months after SCR and 28 months after aLTT. Failure rates were significantly higher in the SCR group than the aLTT group (38.9% vs. 8.9%). Active ROM including forward flexion (161° vs. 131°), abduction (139.3° vs. 100.9°), and external rotation (60.8° vs. 43.8°) was greater among the aLTT group. Patients with Goutallier scores ≥2 who underwent SCR had significantly worse subjective outcomes, ROM, and failure and revision rates than those who underwent aLTT. Outcomes were comparable between SCR patients with Goutallier scores 0-1 and aLTT patients with Goutallier scores ≥2.

CONCLUSIONS

Patients with minimal fatty infiltration of the supraspinatus or infraspinatus are good candidates for SCR augmentation to partial RCR for MIRCT, while patients with high-grade fatty infiltration may benefit from aLTT augmentation. We suggest that a muscle deficit in the form of advanced fatty infiltration is a relative indication for aLTT. If the deficit is more tendinous, however, SCR may be appropriate.