Comparing the Use of Axillary Radiographs and Axial Computed Tomography Scans to Predict Concentric Glenoid Wear.

BACKGROUND: Axillary radiographs traditionally have been considered sufficient to identify concentric glenoid wear in osteoarthritic shoulders; however, with variable glenoid wear patterns, assessment with use of computed tomography (CT) has been recommended. The purpose of the present study was to compare the use of axillary radiographs and mid-glenoid axial CT scans to identify glenoid wear. METHODS: Preoperative axillary radiographs and mid-glenoid axial CT scans for 330 patients who underwent anatomic total shoulder arthroplasty were reviewed. Five independent examiners with differing levels of experience characterized the glenoid morphology as either concentric or eccentric. The morphologies determined with use of axillary radiographs and CT scans were assessed for correlation, and both intraobserver and interobserver consistency were calculated. RESULTS: Concentric wear identified with use of radiographs was confirmed with use of CT scans in an average of 61% of cases (range, 53% to 76%). Intraobserver consistency averaged 75% for radiographs and 73% for CT scans. There was significant interobserver consistency, as higher levels of training corresponded with greater consistency between imaging analyses (p < 0.001). The most senior observer identified the highest proportion of concentric wear on radiographs (p < 0.001), showed the greatest consistency between attempts when using CT (p < 0.001), and had the greatest agreement of radiographs and CT evaluating glenoid morphology (p < 0.001). CONCLUSIONS: For the experienced shoulder surgeon, concentric glenoid wear identified on axillary radiographs will appear concentric on 2-dimensional CT in approximately 75% of cases. Obtaining a CT scan to confirm glenoid wear patterns most greatly benefits less-experienced surgeons. Across all levels of experience, axillary radiographs and single-slice, mid-glenoid CT scans appear insufficient for consistently predicting wear patterns. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Outcomes of anatomic total shoulder arthroplasty in patients with excessive glenoid retroversion: a case-control study.

BACKGROUND: Ideal management of severe glenoid retroversion during anatomic total shoulder arthroplasty (TSA) remains controversial, as previous reports have suggested that severe retroversion may negatively impact clinical outcomes. The purpose of this study was to evaluate the impact of severe glenoid retroversion on clinical and radiographic TSA outcomes using a standard glenoid component, as well as to compare outcomes among patients with less severe retroversion. METHODS: A case-control study was performed comparing 40 patients treated with TSA with more than 20° of glenoid retroversion preoperatively (average follow-up, 53 months) vs. a matched cohort of 80 patients with less than 20° of retroversion (average follow-up, 49 months). In all patients, the surgical technique, implant design, and postoperative rehabilitation protocol were identical. Patients were matched based on sex, age, indication, and prosthetic size. Comparisons were made regarding patient-reported outcome measures (PROMs), motion, postoperative radiographic loosening, and the presence of medial calcar resorption. RESULTS: Preoperatively, both groups demonstrated similar PROMs and measured motion, except for preoperative Single Assessment Numeric Evaluation scores and American Shoulder and Elbow Surgeons total scores, which were higher for the severe retroversion group (44.4 vs. 31.3 [P = .012] and 34.9 vs. 29.4 [P = .048], respectively). Postoperative PROMs and motion were also similar between the 2 cohorts. No significant differences were observed for postoperative radiographic findings. Medial calcar resorption was identified in 74 patients (61.7%). Calcar resorption and individual resorption grades were not found to differ significantly. CONCLUSION: At midterm follow-up, preoperative severe glenoid retroversion does not appear to influence clinical or radiographic outcomes of TSA using a standard glenoid component.

Does radial head implant fixation affect functional outcomes? A systematic review and meta-analysis.

BACKGROUND: Radial head arthroplasty is used in the treatment of nonreconstructible radial head fractures. Although traditional implants have been loosely fixed, smooth stemmed implants functioning more as spacers, modern designs have introduced press-fit, tapered implants that articulate at the capitellum with more rigidly maintained congruity. Cemented implants also use rigid initial fixation. This study was conducted to help determine which fixation method results in better functional outcomes: "fixed" or "unfixed." METHODS: A systematic review and meta-analysis was used. We identified 63 articles via 3 databases. Ten non-English or articles with insufficient text were excluded, and 17 others did not contain sufficient data or follow-up. The remaining 36 articles were qualitatively and quantitatively reviewed. RESULTS: We identified 36 populations, with 878 unduplicated patients: 522 fixed and 356 unfixed. Respectively, mean follow-up in months was 46.2 and 37.4. Average Mayo Elbow Performance Scores were 85.9 and 88.2 (P = .08). Average Disabilities of the Arm, Shoulder and Hand scores were 17.1 and 18.7 (P = .47). Average final flexion/extension arcs were 119.1° and 115.8° (P = .08). Revision rates were 7.9% and 3.1%, and complication rates were 25.5% and 13.2%. Relative risks of revision and complications for the fixed cohort were 2.48 (P = .006) and 1.88 (P < 0.0001), respectively. CONCLUSIONS: Implant fixation type does not appear to affect functional outcomes of radial head arthroplasty. However, rigidly fixing the implant may increase the risks of revision and complications.