Magnetic resonance imaging of the failed superior capsular reconstruction.

BACKGROUND

Superior capsular reconstruction (SCR) of the shoulder is an increasingly common procedure in the treatment of patients with massive, irreparable rotator cuff tears lacking significant osteoarthritis. Post-operatively, the appearance of failed grafts has only been described in isolated case reports and review articles.

METHODS

From January 2016 through December 2017, surgical records at a single tertiary-care facility were queried to identify all patients undergoing SCR. Patient records were reviewed for patient demographic information, reason for post-operative MRI, and post-operative surgeon assessment. 74 patients underwent SCR, of whom 12 received a follow-up MRI post-operatively. One patient was excluded due to missing records; the remaining 11 patients comprise the study cohort. Post-operative MRIs were obtained at mean six months after surgery.

RESULTS

On review of post-operative MRIs, three distinct locations of failure were identified. Four patients (40%) had midsubstance failure of the allograft with all glenoid and humeral head fixation remaining intact. One patient (10%) had complete detachment of the allograft from both glenoid and humeral head fixation. Five patients (50%) had detachment of the allograft from the glenoid.

CONCLUSION

In this series of ten failed SCRs, the most common mode of failure was loss of fixation on the glenoid, followed closely by midsubstance rupture. We found no instances of isolated fixation failure on the humeral head. This series illustrates the need for careful imaging in patients whose post-operative course suggests clinical failure. These findings suggest that strengthening glenoid fixation may provide better clinical outcomes as this procedure becomes more common.

LEVEL OF EVIDENCE: III - Retrospective study.