Background: Rotator cuff repair aims to optimize stability and healing. While double-row (DR) techniques have shown biomechanical advantages, retear rates remain high, especially in the anterior supraspinatus (SSP). This region experiences greater gap formation and strain than the posterior SSP, making it more prone to retears. Purpose: To assess the biomechanical properties of a novel double–double-row (DDR) repair compared with a DR repair. Hypothesis: The DDR repair will exhibit superior biomechanical outcomes than the standard DR repair. Study Design: Controlled laboratory study. Methods: Twelve pairs of fresh-frozen human cadaveric shoulders were mounted to a 6-degree-of-freedom robot. With the humerus at 30° of abduction and external rotation, the SSP line of action was marked. The SSP muscle was dissected, and native tendon stiffness was measured. Each specimen was then repaired with either a DR or a DDR repair. The DR repair used a 6-strand, self-reinforcing construct with three medial and two lateral anchors. The DDR repair added an anterior row to the standard repair. A pressure sensor was placed beneath the repair. The tendon was then cyclically loaded from 25 to 100 N for 3000 cycles and pulled to failure. Repair footprint contacts and failure outcomes were compared. Results: The DDR repair group exhibited a 54% increase in overall contact area (DR, 172 ± 27 mm 2 ; DDR, 266 ± 42 mm 2 ; P < .001), a 92% increase in mean contact pressure (DR, 0.08 ± 0.03 MPa; DDR, 0.16 ± 0.4 MPa; P = .015), a 57% improvement in gapping (DR, 0.7 ± 0.2 mm; DDR, 0.4 ± 0.1 mm; P = .001), and a 57% increase in failure load (DR, 332 ± 119 N; DDR, 520 ± 184 N; P = .025) compared with the DR repair group. Conclusion: Addressing the anterior portion of the SSP in a DDR repair versus a DR rotator cuff repair yields significant increases in contact area and mean contact pressure at the tendon-bone interface, stronger fixation, and reduced gap formation under cyclic loading. Clinical Relevance: DDR repair may enhance healing potential and reduce retear risk, particularly in patients with anteriorly based tears or those at elevated risk due to tissue quality or tear morphology.
Teel et al. (Sun,) studied this question.