From the Research
The best way to diagnose Legg-Calvé-Perthes disease is through a combination of clinical evaluation and imaging studies, with MRI being the most recommended imaging modality due to its ability to detect early changes in blood supply to the femoral head. Initially, a thorough physical examination should be performed, looking for limited hip range of motion, pain with movement, and a limp. X-rays are the first-line imaging test and can show flattening of the femoral head, increased density, and later fragmentation and collapse. However, in early stages, X-rays may appear normal, so MRI is recommended as it can detect early changes in blood supply to the femoral head before they're visible on X-rays 1.
Key Points to Consider
- The diagnosis should be made by an orthopedic specialist, preferably one with experience in pediatric hip disorders, as this condition primarily affects children between 4-10 years old.
- Early diagnosis is crucial because prompt treatment can significantly improve outcomes and prevent permanent hip deformity.
- The diagnostic process should rule out other conditions with similar presentations, such as transient synovitis, juvenile idiopathic arthritis, or hip infections.
- MRI has been shown to be superior to other diagnostic modalities in evaluating the structures of the hip joint components and determining the extent of physeal involvement, which is a strong predictor of prognosis 2.
- The use of MRI in the diagnosis and management of Legg-Calvé-Perthes disease is rapidly evolving, with new techniques and refinements being developed to improve the assessment of hinge abduction and other key factors 3.
Imaging Modalities
- X-rays: first-line imaging test, can show flattening of the femoral head, increased density, and later fragmentation and collapse.
- MRI: recommended for early detection of changes in blood supply to the femoral head, evaluation of physeal involvement, and assessment of hinge abduction.
- Bone scans: may be used to assess blood flow to the femoral head.
- Ultrasound: may be used to evaluate joint effusion and synovitis.
Treatment and Prognosis
- Treatment should be guided by age at disease onset, current best evidence, and prognostic factors, with patients aged <6 years at onset being best managed nonsurgically, and older patients potentially benefiting from surgical treatment 4.
- The Aachen-Dortmund treatment algorithm provides a structured approach to diagnosis, classification, and treatment of Legg-Calvé-Perthes disease, focusing on the preservation or recovery of the arthrogenic containment of the femoral head 5.