Postcode osteoarthritis: geographic inequities in hip and knee arthroplasty

It is suspected that there are differences in access to orthopaedic care within New Zealand (NZ), due to inter-hospital differences in scoring thresholds for surgical eligibility. We aimed to evaluate those patients who meet the threshold for publicly funded surgery with regard to both functional disability and severity of radiographic arthritis across three different public hospitals to assess any discrepancies.

A retrospective review of prospectively collected data over a 12 month period (2018-2019) across three public hospitals (Auckland City, North Shore and Whangārei hospitals) in NZ was performed. Patients undergoing primary hip and knee arthroplasty for OA were eligible for the study. Preoperative Oxford Score and the Tonnis and Kellgren-Lawrence classification systems for hip and knees, respectively, were compared.

A total of 274 scheduled total arthroplasties (161 hips and 113 knees) in 273 patients were included for analysis. The mean Preoperative Oxford scores for individuals with hip OA in Auckland, North Shore and Whangārei were 15.9 (SD 10.5), 14.5 (SD 6.9) and 11.9 (SD 5.7), respectively. The mean Preoperative Oxford scores for individuals with knee OA in Auckland, North Shore and Whangārei were 17.4 (SD 11.9), 18.2 (SD 6.2) and 12.7 (SD 6.9), respectively.

Patients undergoing hip and knee joint replacement surgery in Whangārei hospital are, on average, more functionally impaired and have more severe radiographic arthritis than those having the same proposed surgery in Auckland and North Shore hospitals.