Effect of lateral radiograph on interobserver agreement in Garden classification of intracapsular femoral neck fractures

Abstract

Background: Garden classification is widely used to guide treatment of intracapsular femoral neck fractures, but interobserver reliability remains variable. This prospective observational study assessed agreement in Garden classification and management planning using anteroposterior radiographs alone versus combined anteroposterior and lateral radiographs. Methods: Thirty-five anonymized radiographic sets from adults with intracapsular femoral neck fractures were independently reviewed by 10 orthopaedic observers. Fleiss kappa was used to quantify interobserver agreement. Results: Agreement for Garden classification improved from kappa 0.64 on anteroposterior view alone to 0.76 after adding the lateral view. Agreement for management planning improved from kappa 0.56 to 0.74. Addition of the lateral view changed fracture classification in 61 of 350 observer-case assessments (17.43%) and changed proposed management in 111 of 350 assessments (31.71%). Observers with less than 5 years of experience showed more changes than those with 5-10 years of experience. Conclusions: Addition of the lateral radiograph improved consistency of both Garden classification and treatment planning for intracapsular femoral neck fractures.