Question
A 6 year old boy has a 2 month limp and intermittent knee pain. Radiographs show sclerosis and fragmentation of the left femoral head.
- What is the diagnosis and how is it classified?
- What are the prognostic factors?
- What are the treatment principles?
Answer
Diagnosis and classification
- Legg-Calvé-Perthes disease, idiopathic avascular necrosis of the femoral epiphysis
- Boys aged 4 to 8, small stature and delayed bone age
- Waldenström stages are initial, fragmentation, reossification and healed
- Lateral pillar (Herring) groups A, B, B/C border and C by height of the lateral pillar in fragmentation
- Stulberg classification describes final head shape and congruency
Prognostic factors
- Age at onset, with better outcomes under 6 years
- Lateral pillar group
- Head at risk signs (Catterall), including lateral subluxation, Gage sign, lateral calcification, metaphyseal cysts and a horizontal physis
- Loss of hip motion, especially abduction
Treatment principles
- Maintain range of motion and containment of the femoral head in the acetabulum
- Observation and physiotherapy for children under 6 and lateral pillar A
- Surgical containment with femoral varus or pelvic osteotomy for older children with lateral pillar B or B/C
- Lateral pillar C has a poor prognosis whatever treatment
- Late salvage with shelf, Chiari or valgus osteotomy for hinge abduction
Related pages
Author Contributions
Orthofracs team
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.