Glenoid resurfacing in shoulder arthroplasty: indications and contraindications.

The indications for glenoid resurfacing are controversial. Advantages of glenoid resurfacing include decreased glenoid pain from metal-on-bone articulation, increased stability provided by the conforming glenoid component in the presence of asymmetric glenoid wear, and lateralization of the joint line providing for improved range of motion and strength. Proponents of hemiarthroplasty claim that function and pain relief are equivalent to glenoid resurfacing without the concomitant risk of glenoid loosening and loss of glenoid bone stock. In addition, hemiarthroplasty requires less surgical time and is less expensive than total shoulder arthroplasty. Total shoulder arthroplasty has been shown to be superior to hemiarthroplasty with regard to pain relief, range of motion, and function. Resurfacing of the glenoid has been indicated in older patients with primary osteoarthritis. In addition, patients with rheumatoid arthritis generally have better improvement in pain and function when treated with total shoulder arthroplasty than with hemiarthroplasty. Patients with severe rotator cuff disease, persistent instability, and lack of glenoid bone stock should be treated with hemiarthroplasty alone because glenoid resurfacing is associated with early loosening and failure. Patients with osteonecrosis isolated to the humeral head should be treated with hemiarthroplasty to preserve the native, congruent glenoid.