Background Children with severe cerebral palsy are vulnerable to hip subluxation/dislocation. A proportion will have pathological fractures associated with low bone density.

Management of subluxation may involve orthopaedic surgery with the aim to keep the head of femur in the acetabulum. During a derotation varus osteotomy (DVRO), the proximal femur is surgically divided, a small wedge of bone removed and femoral neck shaft angle tilted to a varus position so that the femoral head lies in the acetabulum. The position of the femur is secured with metal plates and screws.

Case History We present a 10 year old girl with severe cerebral palsy (GMFCS 5). She was known to have a vulnerable left hip and her migration percentage had increased to 50%. By report and clinical assessment there was no evidence of pain from the hip. She was listed for orthopaedic surgery (left hip reconstruction and bilateral DVRO) to take place after insertion of gastrostomy tube.

At review a year later with improved nutrition, the child remained pain free, however a repeat XRay revealed a healed fracture of the left proximal femur resulting in a coxa vara of approximately 90°. This had contained the hip and effectively, achieving the objective of a surgical DVRO. Orthopaedic intervention was postponed.

On close questioning of the family and team around the child – no episodes of pain or traumatic episodes could be elicited. Prior to the gastrostomy the child had required nasogastric tube supplements for suboptimal nutrition. Subsequent bone mineral density scans (DEXA) confirmed Z score 3 lumbar spine and this is being addressed.

She continues under orthopaedic surveillance.

Discussion This is a highly unusual event. Literature search review reveals no other cases of spontaneous fracture of the femur causing a positive effect in a child with cerebral palsy.