Biomechanics of an interlinked suture anchor rotator cuff repair in a human cadaveric model

BACKGROUND: The purpose of this study was to evaluate the initial fixation of a transosseous-equivalent rotator cuff repair and an interlinked medial repair, quantifying the cyclic and failure loading properties of each construct. METHODS: Twenty-four human cadaveric shoulders from 12 matched pairs were dissected, and full-thickness supraspinatus tears were created. In each pair, 1 side was repaired with a transosseous-equivalent repair (control) and the other, with an interlinked repair. All specimens were cycled to 1 MPa of effective stress at 1 Hz for 500 cycles, and gap formation was recorded with a digital video system. All samples were then loaded to failure, and the ultimate load and displacement and modes of failure were recorded. RESULTS: The interlinked repair showed a decrease in the amount of construct gapping after cycle 50 and in peak construct gapping compared with the control group (control, 3.4 ± 0.9 mm; interlinked, 2.5 ± 0.8 mm; P = .048). The interlinked repair also showed a higher ultimate load to failure (control, 318.7 ± 77.9 N; interlinked, 420.6 ± 93.7 N; P = .007). No other significant differences were detected between constructs for preparation or testing metrics. CONCLUSIONS: The interlinked repair, in which 1 continuous suture linked the medial anchors, showed decreased construct gapping and increased ultimate load to failure compared with the control construct. This study establishes the biomechanical validity of the new interlinked repair construct compared with a previously validated construct.