Biomechanical and clinical evaluations of superior capsular reconstruction using autologous tendon for irreparable rotator cuff tear

To evaluate the biomechanical and clinical outcomes of superior capsular reconstruction (SCR) with autologous tendon (AT) for the irreparable rotator cuff tears (IRCTs).

Ten fresh-frozen human upper limb specimens were used to create three models (intact, rotator cuff-deficient, and reconstruction). Superior translation of the humeral head and subacromial pressure were measured at different abduction angles under standardized loading. Mechanical comparability between tendons was also evaluated by measuring cross-sectional area and basic tensile properties. For clinical evaluation, a prospective case series of nine patients with IRCTs tears who underwent SCR with AT was conducted. Shoulder joint range of motion, American Shoulder and Elbow Surgeons (ASES), and Constant-Murley (CM) were recorded before surgery, at 6 months and 12 months after surgery. Magnetic resonance imaging (MRI) was performed preoperatively, the day after surgery, and at 6 months.

The reconstruction reduced superior translation of the humeral head and subacromial pressure compared with the rotator cuff-deficient condition. No significant differences were observed in basic mechanical properties between the tested tendons. ASES scores improved significantly at both 6 and 12 months after surgery, whereas Constant score did not remain statistically significant in the 12-month pairwise comparison after adjustment for multiple comparisons. No significant differences were observed in shoulder joint range of motion. MRI showed 6/9 (67%) patients had reduced thickness of the implanted peroneus longus tendon (PLT) graft at 6 months postoperatively, while the PLT grafts of the other patients remained intact.

SCR with AT may help restore superior glenohumeral stability under controlled biomechanical conditions and shows promising preliminary clinical results in patients with IRCTs.