Aim
To determine the effect on the healing rate in MRI at 12-month follow-up of the addition of a Regeneten Bioinductive Implant (RBI) over a transossseous equivalent (TOE) repair of mid-sized supraspinatus tears.
Background
There is a clear need for biologic enhancement of rotator cuff techniques. The RBI has been proposed as a biological alternative that could increase the healing chances and the quality of the repair.
Methods
Multicentric, triple-blinded, RCT with 12 months follow-up (ClinicalTrials.gov: NCT04444076). Subjects with isolated symptomatic reparable supraspinatus tears smaller than 4cm, without fatty infiltration, were randomized to two groups: In the Control group (CG) an arthroscopic supraspinatus TOE repair was performed; in the Regeneten group (RGT) a RBI was additionally placed over the repair. The primary outcome was the retear rate (defined as Sugaya 4 or 5) in MRI at 12 months follow-up. Secondary outcomes were: characteristics of the healed tendon (thickness at the medial part of the footprint, 10 mm medial and 20mm medial to it) and clinical outcomes.
Results
124 subjects were randomized. Of these, 122 (60 in the RGT group and 62 in the Control group) were available for MRI evaluation one year after the intervention. There were no differences in preoperative characteristics (age, comorbidities, size and retraction of the tear, fatty infiltration) or in complications during the first year of follow-up. One year after the intervention, the re-rupture rate was 8.3% in the RGT group (5/60) versus 25.8% in the Control group (16/62) (significant differences, p=0.010, reduction in risk of rupture of 0.32 [CI-95%: 0.13 to 0.83]). In the 101 healed tendons, the tendon thickness was greater in the RGT group In the 101 healed tendons, the tendon thickness was greater in the RGT group (in the footprint: 4.52±1.83mm vs 3.89±1.82mm ,p=0.023; 1cm medial to it: 4.85±1.74mm vs 4.32±1.84mm, p=0.049).
Conclusion
Adding a Regeneten bioinductive collagen implant to a TOE repair of a medium-sized supraspinatus tear improves the tendon healing rate and increases tendon thickness at one-year follow-up.