1031 - Avascular Necrosis: A Pain in the Hip

Friday, February 20, 2026

5:00 PM - 6:30 PM AST

Presenting Author(s)

SC

Samantha T. Cohen, MD

Resident
Mount Sinai Hospital
New York, New York, United States

Co-Author(s)

AS

Adam T. Schulman, MD

Resident Physician
Mount Sinai Hospital
NYC, New York, United States
AR

Ana Rozman, DO

Attending
Mount Sinai Hospital
New York, New York, United States

Submitter(s)

SC

Samantha T. Cohen, MD

Mount Sinai Hospital
New York, New York, United States

Case Diagnosis: Avascular Necrosis of the Hip

Case Description: The patient is a 35 year old female with a history of glaucoma, neuropathy and alcohol use disorder presenting with right hip pain that began acutely upon descending stairs. The pain was exacerbated with stairs and walking, and radiated to the proximal lateral thigh and distal anterior thigh. She required a cane to ambulate due to pain. On exam, the patient had tenderness to palpation of the proximal quadriceps, pain with resisted hip flexion, and a positive FADIR. Plain hip films were concerning for avascular necrosis (AVN), and MRI demonstrated Stage IIIB AVN. She was referred to orthopedics and underwent intra-articular corticosteroid injection with short-lived relief of pain for 5 weeks. She was then recommended for total hip arthroplasty (THA) with complete relief of pain.

Discussions:
This case will be used as a framework to review AVN staging and interventions. Two classification systems will be reviewed. First, the Association Research Circulation Osseous (ARCO) guidelines are based on imaging and range from I through IV. Stages IIIA and IIIB delineate the threshold of minimal and advanced femoral head (FH) collapse. Next, the Kerboul angle is a composite of the arc of necrotic bone in anteroposterior and lateral images. The angle is then classified as small, medium, or large. Large angles have demonstrated correlation with eventual FH collapse. AVN treatment is aimed at preventing this outcome. Small lesions rarely collapse, thus no intervention is indicated. Patients without, or with minimal, FH collaspe can undergo joint-preserving procedures: core decompression, bone grafting, or osteotomy. Stage IIIB and large Kerboul lesions are indicated for THA given FH collapse has occurred, or will likely occur.

Conclusions: Understanding AVN management guidelines helps guide management and optimize efficient outcomes for patients.