Slipped upper femoral epiphysis (SUFE) is a multifactorial condition usually affecting adolescents. Obesity is one risk factor, and as this is increasing the incidence of SUFE is likely to rise. Diagnosis and treatment are usually straightforward and carried out by orthopaedic surgeons. However, the recognition of post-treatment complications poses a much greater challenge. This article focuses on possible complications of surgical treatment of SUFE particularly. Chondrolysis, avascular necrosis, as well as other complications of treatment and conditions leading to premature osteoarthritis are discussed. Checklists for a systematic approach to post-treatment imaging are provided.