Chronic Lateral Collateral Ligament Complex Insufficiency with Varus Instability

Clinical Presentation

A positive varus stress test indicates lateral collateral ligament complex disruption, which progresses through sequential stages, according to the American College of Radiology, with a strength of evidence not specified 1, 2
Increased gap between radial head and lateral condyle on radiographs demonstrates lateral joint space widening under stress, a hallmark of lateral ligamentous insufficiency, as reported by the American College of Radiology 1
Healed coronoid fracture with 5mm displacement is significant because coronoid fractures are sequelae of prior elbow dislocation and are commonly associated with soft tissue ligamentous injuries that may have been undertreated, as noted by the American College of Radiology 3

MRI without contrast is indicated to assess the current state of the lateral collateral ligament complex, medial collateral ligament, capsule, and any associated tendinous injuries, recommended by the American College of Radiology 4
Stress fluoroscopy can quantify the degree of instability, with <10° widening indicating slight instability, >10° widening indicating moderate instability, and frank redislocation indicating gross instability, which directly impacts surgical planning, as suggested by the American College of Radiology 1, 2

The severe motion restriction combined with instability portends a challenging reconstruction with guarded prognosis, as patients with moderate instability and prolonged immobilization demonstrate significantly worse Mayo Elbow Performance Scores, according to the American College of Radiology 1, 2