OUTCOMES OF SLIPPED UPPER FEMORAL EPIPHYSIS AT MIDDLEMORE HOSPITAL FROM 2004 TO 2024

Introduction Slipped Upper Femoral (or Capital) Epiphysis (SUFE or SCFE) is the most common hip pathology in preadolescents. It has a higher incidence in Pacific Island and Māori patients. Left untreated it can cause life-long morbidity. Middlemore Hospital serves a high proportion of Pacific Island and Māori patients lending to its high-volume experience in treating SUFE. This experience has yet to be reviewed or published in peer-reviewed literature. Objectives To assess outcomes of patients from the past 20 years presenting with SUFE to Middlemore Hospital – focusing on rates of contralateral failure/slippage in patients who did not undergo prophylactic fixation/contralateral pinning, rates of avascular necrosis (AVN), and rates of osteotomy/subcapital realignment procedures. Methods A retrospective review of prospectively collected data. Inclusion criteria being patients who underwent treatment for SUFE at Middlemore in the past 20 years identified from electronic records. Comparative and matched cohort analysis using SPSS. Results 662 patients were identified with SUFE and 579 patients were included in the final analysis after excluding duplicates and patients with insufficient data – yielding a total of 644 hips that received operations. 6.5% were unstable. 82% were pinned in situ. 17.7% had osteotomies. Rate of AVN after osteotomy was 12.9%. 12.8% had prophylactic contralateral pinning. 12.5% of patients who did not have contralateral prophylactic pinning had subsequent contralateral slippage. Mean follow-up was 32 months. Statistically significant factors associated with contralateral slippage were lower age (mean 10.8) and open triradiates (all contralateral slips in our group). Total rate of AVN was 3.3% and chondrolysis rate was 5.4%. Conclusions and Discussion Rates of AVN, chondrolysis and contralateral slippage at Middlemore are comparable to other centres worldwide. Statistically significant factors associated with contralateral slippage were lower age and open triradiate cartilage.