Trethowan's sign

Trethowan's sign is a clinical sign used in the diagnosis of slipped capital femoral epiphysis (SCFE), a common hip disorder in adolescents. The sign is named after British orthopedic surgeon, Sir Harry Platt, who first described it in 1957.

Definition

Trethowan's sign is positive when there is limited internal rotation and pain on forced internal rotation of the hip. This is often associated with an outward turning (external rotation) of the leg. The sign is indicative of a slipped capital femoral epiphysis, a condition where the growth plate (epiphysis) at the top end of the thigh bone (femur) slips backwards and downwards.

Clinical Significance

The presence of Trethowan's sign is a significant finding in the clinical examination of a child or adolescent presenting with hip or knee pain. It aids in the early detection of SCFE, which is crucial as delayed diagnosis and treatment can lead to complications such as avascular necrosis of the femoral head, chondrolysis, and early onset osteoarthritis.

Diagnosis

The diagnosis of SCFE is confirmed by radiographic imaging, typically an anteroposterior and frog-leg lateral view of the hip. However, the presence of Trethowan's sign in the clinical examination can raise the suspicion of SCFE and prompt further investigation.

Treatment

The treatment of SCFE is primarily surgical, aiming to stabilize the slipped epiphysis and prevent further slippage. The choice of surgical procedure depends on the severity of the slip and the skeletal maturity of the patient.

See Also

• Kocher's sign
• Drehmann's sign
• Hip disorders
• Pediatric orthopedics

References

• Platt, H., & Trethowan, W. (1957). Slipped upper femoral epiphysis. Journal of Bone and Joint Surgery, 39(4), 802-825.