A randomized clinical trial to compare the effectiveness of rotator cuff repair with or without augmentation using porcine small intestine submucosa for patients with moderate to large rotator cuff tears: a pilot study

BACKGROUND: The rate of rotator cuff repair failure is between 13% and 67%. Porcine small intestine submucosa (SIS) may be suitable to augment the repair. METHODS: There were 62 patients with moderate and large cuff tears randomized to repair alone (control) or augmentation with SIS (Restore Orthobiologic Implant; DePuy, Warsaw, IN, USA). Primary outcome was repair failure using magnetic resonance arthrography. Randomization occurred on completion of the repair. Patients and assessors were blind to group. Assessments occurred preoperatively and postoperatively at 2 and 6 weeks and 3, 6, 12, and 24 months. RESULTS: There were 62 patients randomized (34 SIS, 28 control). Patient demographics, rotator cuff tear characteristics, and repair details were similar between groups. At 1 year, risk of failure was 52.9% (18/34) in the SIS group and 65.4% (17/26) in the control group for a risk difference of 12% (80% confidence interval, -7% to 32%) or relative risk of 0.81 (95% confidence interval, 0.53-1.24, P = .33) in favor of SIS. At 1 and 2 years, the mean difference between groups for patient-reported outcomes was small and consistent with chance but did not exclude the possibility of a clinically important difference. There was no statistically significant difference (P = .50) between the SIS group (59.6 ± 38.9; range, 3-112) and the control group (52.7 ± 38.6; range, 5-112) in number of days to being narcotic and pain free (<20 mm on a 100-mm visual analog scale). CONCLUSION: We found no evidence that SIS-augmented rotator cuff repair provides superior outcomes in patients with moderate rotator cuff tears.