Morphologic Changes of Synthetic (ePTFE) Interpositional Patch Repair for Massive Irreparable Rotator Cuff Tear

Abstract

Background: Massive, irreparable rotator cuff tears are difficult to manage. One option is to replace the lost tissue with a synthetic patch, for example, expanded polytetrafluoroethylene (ePTFE). There is, however, no information regarding ePTFE patch healing in humans. The aim of this study, therefore, was to evaluate healing of an irreparable rotator cuff tear treated with an interpositional ePTFE patch. Methods: The shoulders of consecutive patients undergoing interpositional ePTFE (Gore-Tex) patch repair for reconstruction of an irreparable rotator cuff tear by a single surgeon were evaluated by an experienced ultrasonographer using a standardized protocol, and by validated patient and examiner outcome measures preoperatively, and at 1, 6, 12 weeks, and 6 months postarthroscopic rotator cuff reconstruction. Results: Ten patients with an average age of 64 years (range, 42 to 85 y) and mean±SEM rotator cuff defects of 20±3.3 cm2 repaired with an ePTFE interpositional graft completed the study. Signs of healing on ultrasound were present at the patch to bone interface in 60% (6/10) of shoulders in a week, whereas 30% (3/10) showed signs of healing at the patch to tendon interface at 12 weeks after surgery. ePTFE patch to tendon thickness was 3.1±0.3 mm a week after surgery, decreasing to 1.9±0.2 mm at 6 months (P=0.05). The patch landing site dimensions (7.3±0.9 mm), thickness at the patch to bone interface (3.7±0.3 mm), and vascularity at the patch to bone and patch to tendon interfaces were unchanged over 6 months. The subacromial bursa was thickened at 1 week postoperatively (2.1±0.2 mm), thinned at 6 weeks (1.7±0.2 mm, P=0.04), thicker at 12 weeks (2.2±0.6 mm), and was within normal thickness after 6 months at 1.2±0.1 mm (P<0.0003). Healing at the patch to bone interface was noted in 10/10 patients, and 9/10 patients at the patch to tendon interface, 6 months after surgery. There were no retears. Frequency and level of pain improved (P<0.05), whereas the shoulders were less stiff (P=0.002). The overall rating of patients on their shoulders improved from very bad to poor before surgery to fair to good 6 months after surgery (P=0.002). Internal rotation, external rotation, and adduction strengths improved 1.6-fold (P<0.05), whereas the supraspinatus strength doubled (P=0.0006). Impingement signs were less at 6 months (P=0.001). Conclusions: This study showed excellent healing of massive, irreparable rotator cuff tears after reconstruction using ePTFE interpositional patch. Signs of healing on ultrasound were present at the patch to bone and patch to tendon interfaces at 1 and 12 weeks, respectively. Patch to tendon interface thickness increased after surgery and gradually decreased in thickness after 6 months, whereas the thickening of the subacromial bursa at 1 week after surgery normalized over 6 months. There were no retears. These morphologic changes were accompanied by improvements in pain, strength, and impingement signs.