This review addresses how to manage glenoid bone deficiency and eccentric posterior wear in shoulder arthroplasty. It covers the full menu of options: hemiarthroplasty with reaming, asymmetric reaming, bone grafting, augmented components, and reverse arthroplasty. The central question is how much retroversion to correct, and by which technique, without wrecking bone stock.
Get a 3-D CT before any case with suspected posterior wear so you can quantify retroversion and bone loss instead of guessing intraoperatively, where soft tissue hides the landmarks.
Use a version-based algorithm. Retroversion under 15 degrees is usually reamable. From 15 to 20 degrees, reaming alone tends to violate the vault, so reach for an augmented component or bone graft. Above 25 degrees (dysplastic, Walch C), bone graft is usually required.
Remember why this matters mechanically: leaving the component too retroverted causes edge loading, shear, and osteolysis, and you cannot fix glenoid retroversion by anteverting the humerus. The key limits to memorize are the 15-degree reaming ceiling and the 1-cm bone-loss threshold separating reaming from grafting.
For an elderly, sedentary patient with a biconcave glenoid and fixed posterior subluxation, reverse arthroplasty sidesteps the soft-tissue balancing problem and gives reliable function.
This review addresses how to manage glenoid bone deficiency and eccentric posterior wear in shoulder arthroplasty. It covers the full menu of options: hemiarthroplasty with reaming, asymmetric reaming, bone grafting, augmented components, and reverse arthroplasty. The central question is how much retroversion to correct, and by which technique, without wrecking bone stock.
Get a 3-D CT before any case with suspected posterior wear so you can quantify retroversion and bone loss instead of guessing intraoperatively, where soft tissue hides the landmarks.
Use a version-based algorithm. Retroversion under 15 degrees is usually reamable. From 15 to 20 degrees, reaming alone tends to violate the vault, so reach for an augmented component or bone graft. Above 25 degrees (dysplastic, Walch C), bone graft is usually required.
Remember why this matters mechanically: leaving the component too retroverted causes edge loading, shear, and osteolysis, and you cannot fix glenoid retroversion by anteverting the humerus. The key limits to memorize are the 15-degree reaming ceiling and the 1-cm bone-loss threshold separating reaming from grafting.
For an elderly, sedentary patient with a biconcave glenoid and fixed posterior subluxation, reverse arthroplasty sidesteps the soft-tissue balancing problem and gives reliable function.