A 12-year-old obese boy presents with groin pain and a limp. Examination shows the affected leg lies in external rotation at rest and internal rotation is markedly restricted. X-ray shows a 'line of Klein' that does not transect the femoral head. What is the diagnosis and appropriate management?

• A Legg-Calve-Perthes disease; conservative management with orthosis
• B Slipped capital femoral epiphysis (SCFE); urgent surgical stabilisation with in-situ cannulated screw fixation ✓
• C Septic arthritis of the hip; emergency arthrotomy and lavage
• D Developmental dysplasia of the hip; pelvic osteotomy

Explanation

SCFE presents in obese adolescents (typically 10–15 years) with groin/thigh pain and obligate external rotation. Klein's line (a line along the superior femoral neck) normally transects the lateral femoral epiphysis; failure to do so indicates posterior and inferior slip of the epiphysis. SCFE is an orthopaedic urgency — further displacement risks AVN. Treatment is urgent in-situ fixation with a single cannulated screw through the physis without attempting reduction (reduction increases AVN risk). Perthes affects younger children with no obligate external rotation finding.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.