Fix it or risk it? Revisiting contralateral hip prophylactic fixation in unilateral slipped capital femoral epiphysis: an updated review of the past decade's literature.

Slipped capital femoral epiphysis (SCFE) is a common hip pathology occurring in pediatrics and adolescents, and its management is well documented in the literature regardless of its severity. In patients presenting with unilateral SCFE, the incidence of subsequent contralateral slip (SCS) is variable among studies, and the issue of contralateral hip prophylactic fixation (CHPF) becomes a concern. The fundamental rationale behind performing CHPF is to avoid the subsequent contralateral slip, which consequently lowers the risk of femoral head avascular necrosis and chondrolysis. However, prophylactic fixation carries the risk of altering proximal femoral growth, peri-implant fractures, and requiring secondary surgery for hardware removal. The current review was formulated based on the literature published in the last decade and aimed to evaluate the incidence of SCS and indications for CHPF. Apart from institutions' protocol or individual surgeons' preferences, various variables were suggested to justify CHPF, including patient-related variables such as the presence of endocrinopathy, those younger than 13 years old (10-13), and patients with mOBAS ≤ 20. Radiological parameters, posterior slip angle ≥ 14.5°, positive crossover sign, posterior epiphyseal tilt of ≥ 10°, alpha angle of ≥ 49°, and a Probability analysis of sequential SCFE (PASS score) of ≥ 3. However, there is still a controversy in the literature regarding CHPF performance and which parameter is highly dependable for predicting the SCS. The controversy extends to the effect and efficacy of various fixation hardware and whether keeping patients under observation is less effective than CHPF. Furthermore, well-designed randomized controlled trials are lacking, and their performance is warranted to establish clear indications for performing CHPF and to clarify its safety, possible consequences, and cost-effectiveness.