Segond Fracture Revealed by Ultrasonography

Abstract

Segond fracture is an eponym that refers to an avulsion fracture of the anterolateral margin of the proximal tibia, just below the lateral plateau. This fracture was described originally in 1879 by French surgeon Paul Ferdinand Segond (1851-1912) in cadaveric experiments. 1 On the anteroposterior view of the knee, the Segond fracture characteristically appears as a small elliptical bone fragment with its long axis oriented vertically, parallel to the proximal tibia. 2 Recognition of this fracture is important because it has a high association with other knee injuries, including anterior cruciate ligament (ACL) tears (75%-100% of cases) and meniscal tears (53%-75% of cases). 2 - 7 The Segond fracture results from excessive internal rotation and varus stress, which cause abnormal tension on the middle portion of the lateral joint capsule (ie, the lateral capsular ligament [LCL] of the knee) and therefore produce an avulsion fracture of the lateral tibial plateau. 1 - 4 The Segond fracture is usually diagnosed on anteroposterior radiographs of the knee; however, some fractures have subtle findings, and the avulsed cortical fragment may be difficult to detect on routine views. 8 At magnetic resonance (MR) imaging, focal bone marrow edema may be seen at the lateral tibial rim, but the bony fragment itself may be overlooked.4 To our knowledge, there is no report of ultrasonographic findings in Segond fracture. We present a case of Segond fracture diagnosed ultrasonographically and confirmed by radiographs and MR imaging.