THE TRAJECTORY OF PATIENT-REPORTED OUTCOMES AFTER HIP PRESERVATION SURGERY: A NATIONAL REGISTRY STUDY

Understanding the trajectory of postoperative patient-reported outcomes after hip preservation surgery is essential. This study is the first to analyse patient-reported outcome trajectories up to two years post-surgery using the UK's national hip preservation registry and to examine potential confounders’ influence. Patients who underwent hip arthroscopy or periacetabular osteotomy with preoperative iHOT-12 scores and at least two follow-up measurements at 6 months, 1 year, or 2 years were included from the UK Non-Arthroplasty Hip Registry. iHOT-12 score trajectories were analysed, and Latent Growth Curve Modelling was used to identify predictors of these trajectories. Overall, 9,845 patients were included in this study. 7,081 patients underwent a hip arthroscopy, and 1,327 patients underwent a periacetabular osteotomy. For hip arthroscopy, there were significant improvements in the iHOT-12 scores from baseline to 6 months [32.2 to 58.2], but no significant change from 6 months to 1 year [mean: 58.0]. However, there was a decrease in the minimal clinically important difference from 1 year to 2 years [mean: 51.7]. For periacetabular osteotomy, there were significant improvements in the iHOT-12 scores from baseline to 6 months [31.7 to 56.0], but no significant change from 6 months to 1 year [55.4], and from 1 year to 2 years [51.3]. Latent Growth Curve Modelling showed that BMI and sex had a significant impact on pre-operative iHOT-12 scores, while age and sex significantly influenced the recovery slope. Patients who underwent hip preservation surgery exhibited significant improvement in iHOT-12 scores, surpassing the minimal clinically important difference at six months postoperatively. This improvement plateaued by two years, with a slight decline in scores between one and two years following hip arthroscopy, though the decrease remained within the clinically meaningful range. BMI, age, and sex influenced score trajectories, highlighting clear preoperative communication with patients.