Reliability assessment of new radiographic scales to evaluate radiolucency and bony in-between fin growth of partially cemented all-polyethylene glenoid components.

BACKGROUND: Current methods available for assessment of radiolucency and in-between fin (IBF) growth of a glenoid component have not undergone interobserver reliability testing for an all-polyethylene fluted central peg (FCP) glenoid. The purpose of this study was to evaluate anteroposterior radiographs of an FCP glenoid component at ≥48 months comparing commonly used scales to a new method adapted to the FCP. Our hypothesis was that the new method would result in acceptable intra- and interobserver agreement and a more accurate description of radiographic findings. METHODS: We reviewed ≥48-month follow-up radiographs of patients treated with a primary aTSA using an FCP glenoid. Eighty-three patients were included in the review. Radiographs were evaluated by 5 reviewers using novel IBF radiodensity and radiolucency assessments and the Wirth and Lazarus methods. To assess intraobserver reliability, a subset of 40 images was reviewed. Kappa statistics were calculated to determine intra- and interobserver reliability; correlations were assessed using Pearson correlation. RESULTS: Interobserver agreement (κ score) was as follows: IBF 0.71, radiolucency 0.68, Wirth 0.48, and Lazarus 0.22. Intraobserver agreement ranges were as follows: IBF radiodensity 0.36-0.67, radiolucency 0.55-0.62, Wirth 0.11-0.73, and Lazarus 0.04-0.46. Correlation analysis revealed the following: IBF to Wirth r = 0.93, radiolucency to Lazarus r = 0.92 (P value <.001 for all). CONCLUSION: This study introduces a radiographic assessment method developed specifically for an FCP glenoid component. Results show high interobserver and acceptable intraobserver reliability for the method presented in this study. The new scales provide a more accurate description of radiographic findings, helping to identify glenoid components that may be at risk for loosening.

Midterm clinical and radiologic survivorship of a stemless total shoulder arthroplasty.

AIM: The aim of this study was to evaluate the clinical and radiologic outcomes of stemless total shoulder arthroplasty (TSA) in patients with glenohumeral arthritis. PATIENTS AND METHODS: This is a retrospective case series of all patients who underwent a TSA with Affinis Short prosthesis during the period 2010-2017. Seventy-two TSAs were performed within our unit, in 62 patients (45 females and 17 males), with 10 patients having bilateral TSAs with this prosthesis. The mean follow-up was 3.9 years (2-8.7 years). Patients were evaluated clinically with the Oxford Shoulder Score, range of movement assessment, and a numerical patient satisfaction score. Follow-up radiographs were evaluated by 2 reviewers assessing for lucency and assigned a Lazarus grade. RESULTS: Six patients were lost to follow-up prior to their 2-year review. At last follow-up, the mean forward elevation was 157° (80°-180°), abduction was 150° (60°-180°), and external rotation was 39° (20°-60°). The mode internal rotation was to the lumbar spine, with 95% of patients achieving internal rotation to L5 or higher. The mean Oxford Shoulder Score was 45 (18-48). The mean patient satisfaction score was 4.93/5. No humeral lucencies were observed. Sixty-four percent (n=47) of the glenoids were Lazarus grade 0, showing no evidence of radiolucency. The remaining patients were Lazarus grade 1-3, although none were progressive and all patients were asymptomatic. No patients were revised for aseptic loosening. Four patients underwent revision: 1 for infection, 1 for heterotrophic ossification and stiffness, and 2 for rotator cuff failure. CONCLUSION: Midterm follow-up results indicate good clinical and radiologic survivorship for this stemless TSA. Our findings suggest good patient function and satisfaction, and no patients have required revision for aseptic loosening. Further follow-up is required to determine long-term survivorship.