THE ASSOCIATION BETWEEN IMPLANT DESIGN, AGE, SEX, AND THE RATE OF MAJOR REOPERATION IN PATIENTS UNDERGOING PRIMARY TOTAL HIP ARTHROPLASTY: AN ANALYSIS OF UK NATIONAL JOINT REGISTRY AND HOSPITAL EPISODE STATISTICS DATA

Major reoperation (hereafter referred to as ‘reoperation’) without revision of implants can leads to significant patient morbidity and mortality, and most commonly occurs when the femur fractures around an implant (postoperative periprosthetic femoral fractures; POPFF) and is treated with fixation and the implant is left in place. Reliance on revision metrics that do not capture these reoperation s has led to large-scale under reporting of failures in THR, and is likely to have affected implant performance estimates, which have guided national policy and implant selection. We aimed to estimate the incidence of reoperation following primary. We analysed a mandatory, prospective database, the National Joint Registry (NJR), linked to Hospital Episode Statistics (HES). All linkable primary THRs using recently available implants, with highest safety rating between 01/01/2010 to 31/12/2020 were included. Reoperation was defined as the first revision for any cause or fixation of POPFF and was identified using a combination of procedural and diagnosis codes. We identified 452,901 THRs representing 2,558,325 prosthesis years at risk. A total of 9,407 reoperations were identified that had been surgically treated by revision for any cause or fixation of POPFF. The incidence of reoperation was 3.68 (95% CI 3.60, 3.75) per 1000 prostheses years in comparison to 3.03 (95% CI 2.96 to 3.10%) per 1000 prostheses years when using conventional revision only outcomes. Cumulative incidence of major reoperation at ten years was 3.0% (95% CI 2.9 to 3.0%). In older men collared cementless stems performed better than cemented stems and in older women the trend was reversed. Rates in older men were lowest with cementless collared stems, and in older women reoperation rates were lowest with cemented polished taper stems made of stainless steel. These results prompt a review of the current implant guidance for hip replacements in older patients.