This is a small retrospective radiographic study quantifying glenoid cartilage wear after shoulder hemiarthroplasty in young, active patients. All had an intact rotator cuff and a normal glenoid at the time of surgery. The question: how much glenoid erosion occurs, and does it track with function?
When you counsel a young, active patient about hemiarthroplasty for a proximal humerus fracture or osteonecrosis, warn them that glenoid wear is not a rare complication but an expected one. In this cohort it happened in every patient, averaging roughly 0.9 mm/year, and painful glenoid arthrosis is the leading reason hemiarthroplasty gets converted to total shoulder arthroplasty.
Follow these patients with serial axillary lateral radiographs, which profile the joint space better than AP views. Watch the residual joint space: once it drops below 1 mm, function falls off (mean Constant-Murley 50% vs 71%) and conversion becomes likely.
The mechanism the authors propose is worth remembering for boards: a prosthetic head that shifts the center of rotation alters cuff and deltoid moment arms, loading the glenoid cartilage abnormally. The major caveat is n=8 with no statistically significant Spearman correlation, so treat the thresholds as a warning signal, not a proven cutoff.
This is a small retrospective radiographic study quantifying glenoid cartilage wear after shoulder hemiarthroplasty in young, active patients. All had an intact rotator cuff and a normal glenoid at the time of surgery. The question: how much glenoid erosion occurs, and does it track with function?
When you counsel a young, active patient about hemiarthroplasty for a proximal humerus fracture or osteonecrosis, warn them that glenoid wear is not a rare complication but an expected one. In this cohort it happened in every patient, averaging roughly 0.9 mm/year, and painful glenoid arthrosis is the leading reason hemiarthroplasty gets converted to total shoulder arthroplasty.
Follow these patients with serial axillary lateral radiographs, which profile the joint space better than AP views. Watch the residual joint space: once it drops below 1 mm, function falls off (mean Constant-Murley 50% vs 71%) and conversion becomes likely.
The mechanism the authors propose is worth remembering for boards: a prosthetic head that shifts the center of rotation alters cuff and deltoid moment arms, loading the glenoid cartilage abnormally. The major caveat is n=8 with no statistically significant Spearman correlation, so treat the thresholds as a warning signal, not a proven cutoff.