This retrospective cohort compared clinical outcomes, radiographic loosening, and cost/value after anatomic total shoulder arthroplasty in patients with concentric versus eccentric glenoid wear. Wear was graded on preoperative CT using a modified binary Levine classification. The question: does preoperative glenoid wear pattern change how patients do after TSA?
When you read a preoperative shoulder CT for TSA, characterize the glenoid wear as concentric or eccentric, not just by version number. Eccentric (biconcave, posteriorly worn, statically subluxed) glenoids behave like Walch B2 morphology and carry roughly double the gross loosening rate, even when early function looks identical.
The teaching point: similar ASES scores at midterm do not mean equivalent durability. Loosening is a radiographic warning that precedes clinical failure, and loosened patients already show worse ASES and pain.
A key nuance for boards: retroversion alone is not the enemy. A retroverted but concentric glenoid can succeed if a stable component is seated, whereas asymmetric wear is the driver of the rocking-horse failure.
This supports escalating preoperative planning for eccentric glenoids, considering augmented glenoids, patient-specific instrumentation, or reverse shoulder arthroplasty rather than routine anatomic TSA.
This retrospective cohort compared clinical outcomes, radiographic loosening, and cost/value after anatomic total shoulder arthroplasty in patients with concentric versus eccentric glenoid wear. Wear was graded on preoperative CT using a modified binary Levine classification. The question: does preoperative glenoid wear pattern change how patients do after TSA?
When you read a preoperative shoulder CT for TSA, characterize the glenoid wear as concentric or eccentric, not just by version number. Eccentric (biconcave, posteriorly worn, statically subluxed) glenoids behave like Walch B2 morphology and carry roughly double the gross loosening rate, even when early function looks identical.
The teaching point: similar ASES scores at midterm do not mean equivalent durability. Loosening is a radiographic warning that precedes clinical failure, and loosened patients already show worse ASES and pain.
A key nuance for boards: retroversion alone is not the enemy. A retroverted but concentric glenoid can succeed if a stable component is seated, whereas asymmetric wear is the driver of the rocking-horse failure.
This supports escalating preoperative planning for eccentric glenoids, considering augmented glenoids, patient-specific instrumentation, or reverse shoulder arthroplasty rather than routine anatomic TSA.