Early to midterm outcomes of anatomic shoulder arthroplasty performed on dysplastic glenoids

Treatment of primary osteoarthritis with glenoid dysplasia or Walch type C glenoids remains controversial. There is scant literature available on patient outcomes after anatomic shoulder arthroplasty in patients with Walch type C glenoids. The purpose of this study was to evaluate the outcomes of total shoulder arthroplasty (TSA) for Walch type C dysplastic glenoids with standard (nonaugmented) glenoid components compared with TSA for glenoids with concentric wear and minimal erosion (Walch type A1). We hypothesized that TSA performed for Walch type C dysplastic glenoids with standard glenoid components can reliably produce successful results at short- to midterm follow-up.

We identified all patients who had primary anatomic TSA performed for osteoarthritis in a prospective shoulder arthroplasty registry collected from 2004 to the present time. Twenty-nine patients met inclusion criteria of a preoperative Walch type C dysplastic glenoid, treatment with TSA using standard (nonaugmented) glenoid components, and a minimum of 2-year clinical follow-up. A matched cohort of 58 patients with a type A1 glenoid and minimum of 2-year clinical follow-up for anatomic shoulder arthroplasty served as the control group. The American Shoulder and Elbow Surgeons (ASES) score, the Single Assessment Numeric Evaluation (SANE), patient satisfaction, complications, and revisions were evaluated in both cohorts.

The mean follow-up for this study was 4.5 years (standard deviation, 2.6 years; range, 2-10 years). Baseline measures were not significantly different between the Walch type C dysplastic group and the matched type A1 cohort (all P > .05). Both groups showed significant improvements in ASES, ASES pain, and SANE scores from baseline to the final follow-up (all P < .001). The Walch type C group had no significant differences in ASES score (P = .118), ASES pain (P = .730), or SANE score (P = .168) compared with the matched type A1 cohort. The complication rate of patients with a type C glenoid was 14% (4 of 29) with a 7% (2 of 29) revision rate. Similarly, the complication rate for the A1 matched cohort was 17% (10 of 58) with a 12% (7 of 58) revision rate. Both groups had high patient satisfaction without statistical differences (P = .549). In addition, there were no differences in the rate of radiographic lucencies or Lazarus scores (P = .222).

Anatomic TSA reliably produced clinically significant improvements in pain and function and similar short- to midterm outcomes in patients with Walch type C dysplastic glenoids compared with patients with type A1 glenoids. Anatomic TSA with standard (nonaugmented) glenoid components should remain an option in patients with Walch type C dysplastic glenoids despite emerging treatment options including augmented glenoid components and reverse TSA.