A rare case of a non-traumatic neck of femur fracture in a 17-year-old boy associated with vitamin D deficiency.

Hip fractures in the young, healthy population are rare and often the result of high-energy trauma. A previously healthy 17-year-old patient presented to our institution with a 5-week history of left hip and knee pain in the absence of any trauma. Pelvic radiograph revealed a subacute left femoral neck fracture. He subsequently underwent surgical fixation and made an uneventful recovery. Further endocrine evaluation revealed isolated vitamin D deficiency to be the likely underlying cause for this fracture. Multiple previous opportunities were missed to identify the cause for this patient's symptoms. An intracapsular fracture in a young adult requires early recognition and prompt anatomical reduction. This case emphasises the need to maintain a high index of suspicion for atraumatic fractures in healthy adolescents with unexplained joint pain. Further endocrine and metabolic investigations are warranted, and isolated vitamin D deficiency must be considered as a potential causative factor.