Does arthroscopic superior capsule reconstruction using porcine dermal xenograft represent a viable option in case of massive irreparable posterosuperior rotator cuff tear?

Introduction: The aim of the present study was to evaluate clinical and structural outcomes of patients with a massive irreparable rotator cuff tear treated with arthroscopic superior capsule reconstruction using an acellular porcine dermal xenograft. We hypothesized that this procedure would lead to improvement in clinical and functional results and that structural failure would not influence the final clinical results. Materials and methods: A retrospective analysis on arthroscopic superior capsule reconstruction performed from October 2016 to January 2019 was conducted. The procedure was performed in patients with a massive irreparable posterosuperior rotator cuff tear without a severe glenohumeral arthropathy (Hamada I and II) and complaining a painful pseudoparalysis. Clinical evaluation and MRI study were performed before surgery and after at least 14 months. Results: A comprehensive group of 21 patients with 11 females and 10 males and a mean age of 57 ± 8.5 years underwent arthroscopic superior capsule reconstruction. The graft had a thickness of 1.5 mm in the first 9 cases (43%) since it was used in a single layer. The graft was thereafter doubled for technique evolution in the following 12 cases (57%) achieving a graft thickness of 3 mm. Active ROM significantly improved with a mean increase of active forward flexion from 72.8° ± 7.5° to 120.6° ± 4.5°, active abduction from 68.3° ± 10.2° to 140.2° ± 8.8° and external rotation from 38.2° ± 11.2° to 56.7° ± 6.8° at the last follow-up. The mean Constant score significantly improved from 40.4 ± 6.7 to 73.3 ± 8.2. A graft tear revealed in 52% (11/21) of overall patients was significantly more frequent in single layer graft when compared to double layer (77% vs 33%, p < 0.05). Location and type of graft tear significantly influenced final outcomes. Patients with a healed (graft continuity with bone at medial and lateral insertion) or medial graft tear showed statistically significant better outcomes when compared with patients in which the graft was completely reabsorbed or torn on humeral side (p < 0.05). Conclusion: Arthroscopic superior capsule reconstruction using an acellular porcine dermal xenograft may be a viable alternative to treat massive posterosuperior rotator cuff tear in patients with a painful pseudoparalysis without anterosuperior escape. Structural failure may strongly influence final outcomes with significant role played by tear location.