Avascular necrosis in antiphospholipid syndrome: pathophysiology, risk factors, and management

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thrombosis and pregnancy morbidity in the presence of antiphospholipid antibodies, which include lupus anticoagulant, anticardiolipin, and anti-β2 glycoprotein I. The updated 2023 ACR/EULAR classification criteria recognize microvascular features of APS but not orthopedic complications. Among these, avascular necrosis (AVN) is an uncommon and underrecognized manifestation, characterized by ischemic death of bone tissue, most often affecting the femoral head, knee, talus, and humeral head. The link between APS and AVN remains unclear and warrants further review.

To explore the association between APS and AVN, focusing on its pathophysiology, prevalence, risk factors, clinical presentation, and management strategies.

A comprehensive search was performed across medical databases, including PubMed, Medline, and Google Scholar, using relevant keywords.

AVN is a rare but significant complication of APS, with prevalence ranging from 0.9 to 20%, depending on the study design and population analyzed. The pathogenesis is primarily attributed to microvascular thrombosis and hypercoagulability caused by antiphospholipid antibodies. Identified risk factors include prolonged glucocorticoid use, thrombocytopenia, pregnancy, and underlying microvascular abnormalities. Early detection via MRI and timely interventions, such as anticoagulation therapy, lifestyle modifications, and surgical procedures, improve patient outcomes and prevent disease progression.

Understanding the multifaceted nature of AVN in APS is crucial for timely diagnosis and effective management. Further research is needed to establish clear preventative strategies and optimize long-term treatment protocols, ultimately improving patient care and clinical outcomes.