This case series reports outcomes of semiconstrained total shoulder arthroplasty using a hooded (Neer 600%) glenoid component for glenohumeral arthritis with massive rotator cuff tearing. It asks whether an oversized glenoid can contain the humeral head and restore function in cuff-deficient shoulders.
When you see cuff tear arthropathy, remember why a standard or hooded glenoid fails. Loss of the rotator cuff force couple lets the deltoid drive the head superiorly, shifting the center of rotation and eccentrically loading the glenoid.
That superior load is the 'rocking horse' mechanism that loosens any fixed glenoid. This paper shows a hooded component does not solve the problem. It merely adds a lever arm that blocks cuff repair and accelerates failure.
The practical lesson is to avoid semiconstrained hooded glenoids in these patients. Historically, hemiarthroplasty was the answer when the coracoacromial arch was intact, providing pain relief and a stable fulcrum without a glenoid to loosen.
This series sits in the evidence arc that discredited constrained and semiconstrained designs and set the stage for reverse shoulder arthroplasty, which reconstructs the fulcrum the deltoid needs.
This case series reports outcomes of semiconstrained total shoulder arthroplasty using a hooded (Neer 600%) glenoid component for glenohumeral arthritis with massive rotator cuff tearing. It asks whether an oversized glenoid can contain the humeral head and restore function in cuff-deficient shoulders.
When you see cuff tear arthropathy, remember why a standard or hooded glenoid fails. Loss of the rotator cuff force couple lets the deltoid drive the head superiorly, shifting the center of rotation and eccentrically loading the glenoid.
That superior load is the 'rocking horse' mechanism that loosens any fixed glenoid. This paper shows a hooded component does not solve the problem. It merely adds a lever arm that blocks cuff repair and accelerates failure.
The practical lesson is to avoid semiconstrained hooded glenoids in these patients. Historically, hemiarthroplasty was the answer when the coracoacromial arch was intact, providing pain relief and a stable fulcrum without a glenoid to loosen.
This series sits in the evidence arc that discredited constrained and semiconstrained designs and set the stage for reverse shoulder arthroplasty, which reconstructs the fulcrum the deltoid needs.