What is the medical term for a disrupted contour of the femoral (thigh bone) head?

From the Guidelines

The medical term for a disrupted contour of the femoral head is femoral head deformity or, more specifically, femoral head irregularity, which can result from various pathologies including osteonecrosis, as defined by the American College of Radiology in 2022 1. This condition can lead to subchondral fracture and secondary osteoarthritis, especially in cases of epiphyseal osteonecrosis, as noted in the 2022 update of the ACR Appropriateness Criteria for Osteonecrosis 1. The disruption in the normal spherical contour of the femoral head affects its congruent articulation with the acetabulum, potentially leading to abnormal joint mechanics and premature osteoarthritis. Key factors to consider in the diagnosis and management of femoral head deformity include:

• The necrotic volume of epiphyseal osteonecrosis, which has been shown to be predictive of future articular collapse, with femoral heads having a necrotic volume of 30% or more progressing to collapse in 46% to 83% of cases 1
• The importance of early diagnosis to exclude other causes of patient’s pain and to allow for possible early surgical prevention to prevent articular collapse and the need for joint replacements, as emphasized in the 2022 ACR update 1
• The role of imaging, including plain X-rays, MRI, or CT scans, in the assessment of the deformity's extent and underlying cause, as well as in preoperative planning, as discussed in the ACR Appropriateness Criteria for Osteonecrosis 1. Treatment approaches vary based on etiology, severity, and patient factors, ranging from conservative management with activity modification and physical therapy to surgical interventions such as osteotomy, femoral head reshaping, or in advanced cases, joint replacement, with the goal of preserving joint function and delaying degenerative changes, as noted in the 2022 ACR update 1.

From the Research

Disrupted Contour of the Femoral Head

The medical term for a disrupted contour of the femoral (thigh bone) head is not explicitly stated in the provided studies. However, the studies discuss various conditions that can lead to a disrupted contour of the femoral head, including:

• Osteonecrosis of the femoral head, which can cause progressive destruction of the hip joint 2, 3, 4, 5
• Avascular necrosis (AVN) of the femoral head, which can result from disruption of the blood supply to the proximal femur 3
• Nontraumatic osteonecrosis, which can lead to a disrupted contour of the femoral head 4

Related Conditions

The studies also discuss various related conditions, including:

• Femoral neck fracture and hip dislocation, which can increase the risk of developing avascular necrosis 3
• Corticosteroid therapy and alcohol abuse, which can also increase the risk of developing osteonecrosis 2, 3, 4
• Trauma, which can cause disruption of the blood supply to the proximal femur and lead to osteonecrosis 3, 4

Diagnosis and Treatment

The studies discuss various methods for diagnosing and treating these conditions, including:

• Imaging studies such as MRI and plain radiography 2, 3, 4, 5
• Core decompression and vascularized bone grafts 2
• Total hip arthroplasty, which is considered the definitive treatment for osteonecrosis of the femoral head 5
• Multidisciplinary approach to diagnosis, which can enhance accuracy and reliability 6