When Bone Loses Blood: Understanding Avascular Necrosis

What happens when a bone loses its blood supply? In this episode, we explore avascular necrosis (AVN)—also called osteonecrosis—a condition where part of a bone begins to die because it no longer receives enough blood flow. Although AVN is uncommon, it can lead to severe pain, joint damage, and even collapse of the affected bone if left untreated.

Using clear and easy-to-understand explanations, we discuss how AVN develops, why certain bones are especially vulnerable, and what causes this condition. You’ll learn how injuries like fractures and dislocations can disrupt blood supply, and why conditions such as steroid use, alcoholism, sickle cell disease, and blood clotting disorders may increase the risk. We also explain why the hip, ankle, knee, and wrist are among the most commonly affected joints.

The episode also explores how AVN progresses over time. Surprisingly, many people initially have no symptoms. However, as the weakened bone begins to collapse, painful arthritis and loss of joint function can develop. We review how doctors diagnose AVN using imaging studies such as X-rays and MRI scans, and explain the different treatment options—from activity modification and protective bracing to surgical procedures designed to restore blood flow, stabilize the bone, or replace a damaged joint.

This podcast is based on trusted, patient-friendly information from the free, peer-reviewed website of the non-profit OrthoEducation, available at OrthoEducation.com, dedicated to helping patients better understand musculoskeletal conditions.