Hip

Hip pathology in children may present with pain in the groin, thigh or knee, as pain is often referred from the hip joint. It is important to consider extra-articular causes, including hernia, testicular pathology, spinal problems (particularly the sacroiliac joints), pelvic or abdominal disease.

Red flag features

Serious causes of hip pain include infection (septic arthritis or osteomyelitis) and, more rarely, malignancy. Any child who is acutely unwell, with fever, inability to weight bear or systemic features, should be urgently assessed.

Slipped upper (capital) femoral epiphysis (SUFE/SCFE)

SUFE is a displacement of the femoral head epiphysis and most commonly occurs during the adolescent growth spurt, typically between 10 and 15 years of age. Risk factors include obesity and endocrine disorders such as hypothyroidism.

Children may present acutely with severe pain and inability to weight bear, or more gradually with hip, groin or knee pain, limp and restricted movement. The condition is usually unilateral but may be bilateral.

SUFE may also occur in children with juvenile idiopathic arthritis, and should be suspected in any child with JIA who develops a sudden limp or restriction of hip movement.

Diagnosis is confirmed on hip radiographs, and urgent orthopaedic referral is required. Treatment is surgical, and delay in management increases the risk of avascular necrosis, early osteoarthritis and long-term disability.

Legg–Calvé–Perthes disease

Perthes disease is avascular necrosis of the femoral head due to interruption of its blood supply. It most commonly affects boys aged 4–8 years.

Children may present with an acute or gradual limp, sometimes with refusal to weight bear, and hip or groin pain.

Management requires urgent orthopaedic referral. Treatment usually involves rest and positioning in abduction, and delayed diagnosis can result in poor joint development and early osteoarthritis.

Developmental dysplasia of the hip (DDH)

Developmental dysplasia of the hip results from abnormal development and instability of the hip joint. It may be identified during the newborn or 6-week examination, and may be unilateral or bilateral.

Risk factors include family history and breech presentation, and these infants should undergo screening hip ultrasound.

Some children present later, as toddlers or older children, with a limp, hip pain or referred knee or thigh pain. Clinical signs may include leg length discrepancy, asymmetrical skin creases, external rotation of the affected limb or tip-toe walking.

Early diagnosis and prompt referral to orthopaedic services are essential to prevent long-term disability.