Atraumatic elbow avascular necrosis in the adult is rare, multifocal, and associated with systemic corticosteroid use.

Background: Atraumatic avascular necrosis (AVN) of the elbow is a rare diagnosis with little literature describing features of this pathology. The purpose of this study is to investigate atraumatic elbow AVN in adults, with a focus on the anatomic distribution of AVN within skeletally mature elbows. Methods: A retrospective chart review was conducted on six patients who were identified via term searches of elbow magnetic resonance imaging (MRI) done at the authors' institution that also had appropriate diagnoses. Terms included "necrosis", "AVN", and "avascular". Demographic data were collected, including age of diagnosis, sex, associated comorbidities, use of steroids, use of chemotherapeutic agents, alcohol consumption, smoking status, and associated joint involvement. Clinical information regarding presentation and treatment course were also gathered. Both plain film and MRI were evaluated for identification of anatomic involvement of disease and staging. Results: Six patients were included in the study: three men and three women with a mean age of 26.5 years (17-46) at time of diagnosis. All patients presented with elbow pain and one patient presented additionally with loss of full range of motion. Four of the six patients had a prior cancer diagnosis (T-cell acute lymphoblastic leukemia x2, follicular lymphoma, acute myeloblastic leukemia) that led to chemotherapy exposure, and two of them had additional steroid therapy. Another two had autoimmune diseases (systemic lupus erythematous and dermatomyositis) that required high dose steroid therapy. At time of initial imaging, the capitellum was involved in 8 of 9 elbows, the trochlea in 8 of 9 elbows, the radial head in 4 of 9 elbows, the proximal ulna in 2 of 9 elbows, and the olecranon in 1 of 9 elbows. Only one elbow had additional sites of the elbow affected at future follow-ups. One patient presented with AVN of the capitellum, trochlea, and ulnar neck, and two years later had signs of olecranon osteonecrosis on MRI. Two patients underwent operative treatment with resolution of symptoms. Conclusion: This study describes the anatomic incidence of AVN of the elbow. Most involved are the capitellum and trochlea, with involvement in the radial head, proximal ulna, and olecranon also being observed. This information can be used to help orthopedic surgeons in their diagnosis and clinical decision making for affected patients.