Avascular necrosis of the femoral head: management remains controversial

Abstract

Management of pre-collapse atraumatic avascular necrosis of the femoral head remains a controversial topic. We conduct this scoping literature review to discuss current perspectives on management. Avascular necrosis of the femoral head (AVNFH) is a progressive pathology of the hip. If left untreated, 80% of cases progress to collapse of the femoral head and require total hip arthroplasty (THA). It is the third commonest reason for THA in the UK (and this proportion is even higher in other parts of the world) and, compared to other indications for THA, affects a disproportionately young population. Successful management demands early diagnosis and interventions to prolong native hip-joint preservation and delay femoral head collapse. Pathophysiology is poorly understood and aetiologies are varied. The ultimate cause of the disease is loss of blood supply to the proximal femur. AVNFH can be traumatic (fracture or dislocation) or atraumatic (80% due to corticosteroid use or alcohol excess). Traumatic causes of AVNFH require accurate and expedient management to prevent AVNFH post-injury. Fixation of fractures requires anatomical reduction to reduce the risk of AVNFH. Dislocation of the proximal femur requires reduction within 12 hours. Hips reduced after this time are much more likely (5.627 odds ratio) to suffer AVNFH. Atraumatic AVNFH can be managed conservatively, pharmacologically or surgically. Surgical interventions such as core decompression or osteotomy have a large body of evidence demonstrating that they can improve symptoms, delay progression and reduce the need for conversion to THA. There are many emerging augmentation procedures, and variations to established procedures, that utilize non-vascularized bone grafts, vascularized bone grafts and bone morphogenetic protein. There is a growing body of evidence to suggest that these augmentations improve outcomes.