E1049. A Chip Off the Old Block: Head-to-Toe Radiographic Review of Avulsion Fractures and Associated Soft Tissue Injuries
  1. Robert Dionisio; Santa Barbara Cottage Hospital
  2. Bernard Chow; Santa Barbara Cottage Hospital
Review common traumatic avulsion fractures seen on radiographs and their associated pathophysiology. Discuss associated soft tissue injuries usually not readily visible on initial x-ray examinations.

Educational Goals / Teaching Points
Avulsion fractures typically result from trauma of varying chronicity. In the acute setting, extreme activity and/or range of motion results in an abnormal and unequal opposing tension from tendinous/ligamentous/capsular forces overpowering the tensile strength of bone. Subacute-chronic injuries result from repetitive overuse. Symptoms vary largely on the type of injury, severity, and associated structural involvement, and include pain, instability, and irregular biomechanics. Treatment is determined similarly and ranges from conservative (casting/splinting, immobilization, etc) to surgical measures. Treatment goals include anatomic reduction, early return to function, prevention of irreversible sequelae, and improved cosmetics. In this exhibit, we will discuss avulsion fractures of the extremities commonly encountered on radiographs and often associated underlying stabilizer soft tissue injuries.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Shoulder/elbow including tuberosity, epicondyle, triceps/biceps; hand/wrist including UCL, triquetral, trapeziometacarpal, phalange, ECR; pelvis including ASIS, AIIS, trochanteric, ischial tuberosity; knee including Segond, Stieda, cruciate ligaments, IT band, arcuate complex, patellar sleeve, tibial tubercle; and ankle/foot including 5th metacarpal, calcaneum.

Avulsion fractures due to trauma may be indicative of underlying, hidden soft tissue injury. If seen on initial radiographs, it is important to understand common involved structures and when to recommend further imaging that may necessitate intervention to prevent significant long-term morbidity.