Juvenile osteochondrosis of head of femur, unspecified leg

This code signifies Legg-Calve-Perthes disease, a childhood hip disorder characterized by avascular necrosis of the femoral head. It involves the temporary loss of blood supply to the growth plate of the femoral head, leading to bone death and subsequent collapse. This specific code indicates the condition is present but the affected leg (left or right) is not documented.

Apply this code when documentation confirms a diagnosis of Legg-Calve-Perthes disease without specifying laterality. This is appropriate for initial diagnoses where the affected side is not yet determined or if the medical record simply states "Legg-Calve-Perthes" without further detail. Avoid using this code if the laterality is known.

• Always strive for greater specificity; if laterality is documented (e.g., M91.11 for right, M91.12 for left), use the more precise code.
• This code is for an unspecified leg; if bilateral involvement is documented, use M91.13.
• Ensure the documentation clearly states "Legg-Calve-Perthes" or "juvenile osteochondrosis of head of femur" to support this diagnosis.