PATIENT CHARACTERISTICS AND OTHER FACTORS INFLUENCING FIXATION TYPE IN PRIMARY TOTAL HIP ARTHROPLASTY: NATIONAL SURVEY AMONG UK ORTHOPAEDIC SURGEONS TO INFORM HIPPY TRIAL

The HIPPY Programme aims to find out which method of fixation of hip implants are best for patients under 70 years and includes a randomised controlled trial of cemented, uncemented, and hybrid constructs. To inform the trial, we conducted a national survey of UK consultant hip surgeons to explore and understand how implant choices are made. The online survey was facilitated by the British Hip Society and launched in January 2024. The survey comprised structured questions on practice and a discrete choice experiment (DCE) to explore what patient characteristics influence surgeons’ choice of fixation methods. Surgeons were presented with 10 patient profiles described by age, sex, activity level, risk of medical problems, and fracture risk, and were asked to indicate whether they would choose a cemented, uncemented, or hybrid construct for each patient profile. 101 consultants performing hip replacement on average for 12.5 years (SD 8.5) completed the survey. Consultants performed a mean of 121 (SD 81) primary total hip replacements per year. For patients aged under 70 years, 60% would use hybrid, 31% uncemented and 9% cemented implants. For patients 70 years or older, 55% would use hybrid, 11% uncemented, 33% cemented and 1% reverse hybrid. In the DCE, the most influential patient characteristics were patient age and activity level. For a moderately active man, the probability of choosing a cemented implant was 10% at the age of 65 and 39% at the age of 85. These probabilities were 15% and 47% for a woman respectively. Perceived fracture risk significantly decreased the probability of choosing an uncemented implant. 24 surgeons chose the same implant type for all 10 patient profiles. In a rating exercise using a scale from 1–4, the most influential factors were revision rate (3.7), personal practice audit (3.5), published evidence/NICE guidelines (3.5), patient's age (3.4) and anatomy (3.2). This survey provided information on how surgeons choose implants for their patients and helped us to identify surgeons willing to join the HIPPY RCT.