Segond fracture: involvement of the iliotibial band, anterolateral ligament, and anterior arm of the biceps femoris in knee trauma

To evaluate the involvement of the iliotibial band (ITB), the anterolateral ligament (ALL), and the anterior arm of the biceps femoris in MRI-diagnosed Segond fracture and to evaluate other associated findings of Segond fracture. We retrospectively reviewed the MRI of 13 cases of Segond fracture. The studies included proton density-weighted, T2-weighted, and proton density-weighted with fat saturation images in the three planes. We studied 2 cadaveric specimens with emphasis on the ALL. One cadaveric specimen was dissected while the other was sectioned in the sagittal plane. The mean age of the patients was 36 years (range, 17-52). There were 7 men and 6 women. The mean size of the Segond bone fragment was 8 x 10 x 2 mm. The distance from the tibia varied from 2 to 6 mm. Associated findings included anterior cruciate ligament (ACL) tear (n = 13), medial collateral ligament (MCL) tear (n = 8), meniscocapsular tear of the posterior horn of the medial meniscus (n = 5), and posterolateral corner involvement (n = 4). Bone marrow edema involved the mid-lateral femoral condyle and the posterior tibial plateau on both the medial and the lateral side. Edema at the Segond area was seen, but was limited. Fibular head edema was also seen. The ITB (11 out of 13) and ALL (10 out of 13) inserted on the Segond bone fragment. The anterior arm of the biceps tendon did not insert on the Segond fracture. Associated findings of Segond fracture include ACL tear, MCL tear, medial meniscus tear, and posterolateral corner injury. Both the ITB and the ALL may be involved in the Segond avulsion. The anterior arm of the biceps femoris tendon is not involved.