Abstract
Background: Superior capsule reconstruction (SCR) was developed to restore superior glenohumeral stability and function to shoulder joints with irreparable rotator cuff tears. Previous biomechanical studies have investigated the effects of SCR using dermal graft or freeze-dried fascia lata allograft. The objective of the current study was to investigate the effect of SCR using fresh-frozen fascia lata graft, which closely resembles the fresh fascia lata autograft used clinically, on shoulder biomechanics in irreparable rotator cuff tendon tear. Methods: Eight fresh-frozen cadaveric shoulders were tested by using a custom testing device. Subacromial peak contact pressure (pressure sensor), superior glenohumeral translation (three-dimensional digitizing system), and glenohumeral range of motion (goniometer) were compared under three conditions: (1) intact shoulder; (2) simulated irreparable rotator cuff (supraspinatus and infraspinatus) tear; and (3) SCR using fresh-frozen fascia lata graft. SCR was performed according to the technique for SCR using fascia lata autograft. The average graft thickness was 8.6 mm at the medial edge and 8.9 mm at the lateral edge. Results: Compared with the intact condition, creation of the irreparable rotator cuff tear increased superior translation and subacromial peak contact pressure at 0° (P < 0.01) and 30° (P < 0.001) of glenohumeral abduction. SCR using fresh-frozen fascia lata graft decreased superior translation and subacromial peak contact pressure to the intact level (P < 0.01 for both). SCR using fresh-frozen fascia lata graft did not decrease internal (P = 0.15 to 0.99), external (P = 0.90 to 0.99), or total (P = 0.35 to 0.98) rotation at 0°, 30°, or 60° of glenohumeral abduction, compared with the irreparable supraspinatus and infraspinatus tendon tear condition. Conclusion: For irreparable supraspinatus and infraspinatus tendon tear, SCR using 8 mm-thick fresh-frozen fascia lata graft restored superior glenohumeral stability to the intact level without any restriction of glenohumeral range of motion after surgery. © 2025 The Japanese Orthopaedic Association