Editorial Commentary: Can Passive Muscle Stiffness in a Cadaveric Study Be Clinically Related to Using Knotted Versus Knotless Rotator Cuff Repair?

Is a biomechanical cadaveric study to assess the effect of rotator cuff tear size and repair technique on supraspinatus muscle stiffness clinically relevant? A study in this issue compared double-row and knotless transosseous-equivalent repairs, but notably, muscle loading was not simulated. Results showed that the knotless transosseous-equivalent repair for larger tears demonstrated a more uniform stiffness distribution across the supraspinatus muscle compared with the double-row repair. However, given the inherently asymmetrical functional anatomy and morphology of the supraspinatus tendon-muscle unit, when muscle tone exists, the effect of the repair technique on muscle stiffness in vivo may not be determined based on the findings of this study.