METHODS: A comprehensive systematic search was conducted across PubMed, EMBASE, Web of Science, Cochrane Library, and Chinese biomedical databases (China National Knowledge Infrastructure [CNKI], Wanfang, VIP) to identify eligible case-control studies published through October 2025 examining the association between the MTHFR C677T polymorphism and LCPD. This evidence concerns the gene MTHFR and Legg-Calve-Perthes disease.