Augmentation of a Posterosuperior Cuff Repair With a Bovine Bioinductive Collagen Implant Shows a Lower Retear Rate but Similar Outcomes Compared With No Augmentation: 2-Year Results of a Randomized Controlled Trial

Abstract

Purpose: To assess the clinical and radiologic outcomes of the addition of a bioinductive collagen implant (BCI) to repair of medium to large posterosuperior rotator cuff tears at 24-month follow-up.

Methods: This study was an update of a randomized controlled trial that was extended from 1- to 2-year follow-up. A total of 124 subjects with symptomatic full-thickness posterosuperior rotator cuff tears with a fatty infiltration grade of 2 or less per the Goutallier classification were randomized into 2 groups in which a transosseous-equivalent repair was performed alone (control group) or with a BCI applied over the repair (BCI group). The outcomes reassessed at 2-year follow-up were as follows: Sugaya grade, retear rate and tendon thickness on magnetic resonance imaging (MRI), and clinical outcomes (pain level, EQ-5D-5L score, American Shoulder and Elbow Surgeons [ASES] score, and Constant-Murley score [CMS]).

Results: There were no relevant differences in preoperative characteristics between the groups. There were no additional complications or reinterventions in the second year of follow-up. Of 124 randomized patients (59 male and 55 female patients; mean age: 58.1 years [standard deviation (SD), 7.35 years]), 114 (91.9%) underwent MRI evaluation at 25.4 months (SD, 1.95 months) after surgery. There was a lower retear rate (12.3% [7 of 57]) in the BCI group compared with the control group (35.1% [20 of 57]) (P = .004; relative risk of retear, 0.35 [95% confidence interval, 0.16-0.76]). The Sugaya grade was also better in the BCI group (2.58 [SD, 1.07] vs 3.14 [SD, 1.19]; P = .020). Clinical follow-up was performed in 114 of 124 patients (91.9%) at 25.8 months (SD, 2.75 months) and showed improvements in both groups (P < .001), with 87% achieving the minimal clinically important difference for the CMS and 90% doing so for the ASES score; however, there were no differences between the groups. Among subjects who underwent both MRI and clinical assessment (n = 112), those with an intact tendon presented better CMS values (P = .035), ASES scores (P = .015), and pain scores (P = .006) than those with a failed repair.

Conclusions: Augmentation of a transosseous-equivalent repair with a BCI in posterosuperior rotator cuff tears clearly reduces the retear rate at 2-year follow-up without increased complication rates and with similar clinical outcomes. Subjects with failed repairs had poorer clinical outcomes.

Level of evidence: Level I, randomized controlled trial.