Retrospective case-control study of 57 patients after arthroscopic double-row repair of an isolated full-thickness supraspinatus tear. It asks whether scapular morphology, measured by critical shoulder angle, acromion index, and glenoid inclination, predicts retear on 6-month MRI.
Measure the critical shoulder angle on a true AP radiograph before offering an isolated supraspinatus repair, and flag any patient above 38 degrees as high-risk for retear. The mechanism is biomechanical: a steep CSA increases the shear-to-compression ratio at the joint, overloading the supraspinatus and straining the repair.
Because acromion index tracked with failure but glenoid inclination did not, the authors reason the risk comes from a wide lateral acromion, not glenoid tilt. This matters because a standard anterior acromioplasty does not touch the lateral acromion and so does not reduce the CSA.
Interpret this cautiously: it is a Level III case-control study of only 57 patients, the confidence interval for the CSA difference was wide, and retear at 6 months did not worsen any functional score. Whether lateral acromioplasty to lower the CSA actually reduces retears is unproven and remains debated.
Retrospective case-control study of 57 patients after arthroscopic double-row repair of an isolated full-thickness supraspinatus tear. It asks whether scapular morphology, measured by critical shoulder angle, acromion index, and glenoid inclination, predicts retear on 6-month MRI.
Measure the critical shoulder angle on a true AP radiograph before offering an isolated supraspinatus repair, and flag any patient above 38 degrees as high-risk for retear. The mechanism is biomechanical: a steep CSA increases the shear-to-compression ratio at the joint, overloading the supraspinatus and straining the repair.
Because acromion index tracked with failure but glenoid inclination did not, the authors reason the risk comes from a wide lateral acromion, not glenoid tilt. This matters because a standard anterior acromioplasty does not touch the lateral acromion and so does not reduce the CSA.
Interpret this cautiously: it is a Level III case-control study of only 57 patients, the confidence interval for the CSA difference was wide, and retear at 6 months did not worsen any functional score. Whether lateral acromioplasty to lower the CSA actually reduces retears is unproven and remains debated.