Clinical case: Avascular necrosis of the femoral head and acetabular fossa with a massive bone defect

Abstract

Avascular necrosis (AVN) is a progressive disorder caused by an insufficient blood supply to the bone, which, if left untreated, can lead to infarction — most commonly affecting the femoral head. The femoral head is particularly vulnerable due to its limited vascular supply, and disease progression in this region can be debilitating, often culminating in the need for total hip arthroplasty (THA).
AVN can result from both traumatic and non-traumatic causes of ischemia. Diagnosis is typically based on clinical symptoms, patient history, and characteristic radiographic findings.

The patient presents with a complex medical history, including dysplastic coxarthrosis, avascular necrosis (AVN) of the femoral head and congenital dislocation of the femoral head. In infancy, the patient underwent conservative treatment, including plaster casts. The patient also has a history of Legg-Calvé-Perthes disease.

Physical Examination: Upon examination, the patient’s lower limb is shortened by 5 cm. Over the past 5 years, the patient has reported progressively increasing pain in hip area, significantly limiting mobility and daily functioning.

Diagnosis: The diagnosis of avascular necrosis and acetabular necrosis was confirmed through radiographic imaging, which revealed significant damage to both the femoral head and the anterior and superior walls of the acetabular fossa. The imaging also showed extensive bone loss, necessitating a more complex surgical intervention.

Surgical Intervention: This case presents a rare and complex scenario of simultaneous AVN of the femoral head and necrosis of the acetabular fossa, resulting in a large bone defect. Given the extent of acetabular destruction, bone grafting was required, along with fixation using a double-mobility implant—a technique typically reserved for revision surgeries or patients at high risk of instability.

Outcome: Intraoperatively, complete restoration of the acetabular fossa walls was achieved, and stable fixation of the implant was confirmed. After a 4-year follow-up, the patient demonstrated full functional recovery, with radiographic evidence of successful adaptation and integration of the transplanted bone graft.

AVN, especially with concurrent acetabular necrosis, poses significant challenges. The use of double-mobility implants, typically reserved for high-risk cases, provided enhanced stability and long-term success in this patient. The severity and distribution of necrosis, combined with the complexity of the required surgery, make this case a valuable contribution to orthopedic literature.

This case demonstrates the successful management of simultaneous avascular necrosis (AVN) of the femoral head and acetabular necrosis, treated with bone grafting and double-mobility implant fixation. The patient achieved full functional recovery with stable radiographic outcomes after 4 years of follow-up, highlighting the effectiveness of these techniques in addressing complex hip joint destruction.