Segond fracture is known as small avulsion fracture from proximal tibia just distal to tibial plateau. A 56-year-old female patient referred to our emergency department with the complaints of knee pain, restricted motion and difficulty on walking. According to her statement her right foot was caught in a gap on the street and she fell aside on her knee, twisting on her right foot. On her physical examination lateral and anterolateral laxity and Lachman test was positive. On her radiographs, an avulsion fracture on lateral tibial plateau and a fissure on fibular head were observed. Magnetic resonance imaging revealed separation of lateral capsular ligament and fibular collateral ligament from their insertions on femur. Arthroscopy was carried out to the patient initially. Intraarticular structures were found to be normal except for previous rupture of anterior cruciate ligament and minimal degenerative changes on cartilage tissue. Then fibular collateral ligament and lateral capsular ligament were repaired by a lateral approach. Avulsed fragment was found in the posterior fibers of iliotibial ligament and fixed by two screws. Fragment was seen to be united in the follow up visits and all signs of instability except for the Lachman test disappeared. In this article we aimed to emphasize that, in a patient with previous rupture of anterior cruciate ligament, which is a primary resistance to mechanical forces, Segond fracture predominantly causes injury to lateral ligamentous structures.
Keywords: Lateral avulsion, anterior cruciate ligament, Segond fracture
