Idiopathic avascular necrosis of the femoral head in young rhythmic gymnasts: a clinical and radiological assessment

BACKGROUND: Osteonecrosis of the femoral head is a severe and rapidly progressive degenerative-dystrophic disorder and is commonly detected in children professionally engaged in rhythmic gymnastics. It is characterized by destructive changes in the femoral head, resulting in hip joint function impairment and, consequently, poor clinical outcomes. The radiographic anatomy of the hip joints is insufficiently studied, especially considering the impact of intense and specific physical loads, course and progression of the disease, and reasons behind its delayed diagnosis and late initiation of treatment. AIM: To provide a clinical and radiological characterization of the hip joints in young rhythmic gymnasts diagnosed with idiopathic avascular necrosis of the femoral head and identify factors contributing to delayed diagnosis and late treatment initiation. METHODS: Medical histories and imaging findings of 45 young rhythmic gymnasts aged 12–17 years diagnosed with idiopathic avascular necrosis of the femoral head were analyzed. RESULTS: Most patients exhibited a severe clinical course due to total or subtotal involvement of the femoral head. Distinctive anatomical features of the hip joint in young rhythmic gymnasts included dysplastic morphology with impaired stability indices, valgus epiphyseal formation resembling a Kalamchi type II deformity, and a tendency toward acetabular retroversion. These characteristics contributed to the development of pathological changes, such as femoral head extrusion and deformation. Delayed diagnosis and initiation of treatment was due to insufficient awareness of this pathology among parents, coaches, and physicians; gradual development of clinical symptoms without a history of overt trauma; and diagnostic errors during the early stages of the disease. CONCLUSION: In adolescents, their congenital anatomical features of the hip joint contribute to a more severe course of avascular necrosis of the femoral head. Early differential diagnosis of hip pain in gymnasts, including the use of magnetic resonance imaging, is crucial to exclude femoral head osteonecrosis.