Submit Manuscript | http://medcraveonline.com Abbreviations: ALL, anterolateral ligament; ITB, iliotibial band; MRI, magnetic resonance image; ACL, anterior cruciate ligament; PCL, posterior cruciate ligament; MCL, medial collateral ligament; PLC, postero-lateral corner Introduction The Segond fracture is defned as an avulsion of the proximal anterolateral tibial plateau region originally described by the French surgeon Paul Ferdinand Segond in 1879. 1,2 This injury is widely accepted as a pathognomonic radiographic marker of anterior cruciate ligament (ACL) injury. 1‒3 However, some reports describe this injury in the presence of an intact ACL in skeletally immature patients. 4‒5 Recent anatomical and histological studies had described the anterolateral knee ligament (ALL). 6‒9 This structure defned by Dr. Segond initially in the nineteenth century has been receiving different nomenclatures until recently be assigned as ALL. 10 Proximally, the ALL originates near the lateral femoral epicondyle and inserts distally on the lateral meniscus and the anterolateral tibial edge, halfway between Gerdy’s tubercle and the fbular head. This is the exact site of the Segond fracture according to a study by Claes et al. 12 describing ACL injuries associated with this type of avulsion. 6‒11 A retrospective MRI analysis of ACL injuries indicated changes in the ALL images in 78.8%. 12 The purpose of this case report is to demonstrate an isolated Segond fracture coursing with anterolateral knee instability without ACL neither other knee ligament injuries in an adult patient. The lesion was surgically treated presenting good results at two years follow-up. Case report A 24-year-old female suffered a knee sprain after being hit by a motorcycle at low speed. She complained of lateral proximal pain in her right leg at her frst medical visit. After performing X-rays, the informed diagnosis at her frst evaluation at other service was contusion of the proximal leg. The leg was immobilized for two weeks followed by rehabilitation. Three months after the accident, she came to our outpatient clinic complaining of pain and instability of the right knee presenting frequent giving away episodes. During the clinical examination, she presented normal gait and normal range of motion. The Lachman test showed slight anterior translation with a frm endpoint as well as the anterior drawer test when compared to the normal side, being both classifed as grade B (nearly normal). The pivot-shift test was positive and classifed as grade C (abnormal). 13 The Lysholm scale 14 applied questionnaire score was rated as poor (43 scores). Knee radiographs revealed the Segond fracture (Figure 1A) (Figure 1B). The patient underwent an MRI and a computed tomography (CT). Both CT and MRI showed the Segond fracture. The MRI showed integrity of the ACL, posterior cruciate ligament (PCL), medial collateral ligament (MCL), posterolateral corner (PLC) structures and menisci (Figure 2A-2E). Figure 1 (A) Anteroposterior radiography demonstrating the Segond fracture. (B) Lateral radiograph The authors opted for surgical treatment due to frequent instability complaints and the presence of the Segond fracture. In addition, the patient had not improved after three months of conservative MOJ Sports Med. 2017;1(6):142‒144 142 © 2017 Ferreira et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Absolute isolated avulsion of the anterolateral complex of the knee: a segond fracture Volume 1 Issue 6 - 2017 Marcio de Castro Ferreira, Flavio Ferreira Zidan, Francini Belluci Miduati, Caio Cesar Fortuna, Carlos Eduardo da Silveira Franciozi, Rene Jorge Abdalla Department of Ortopedics, Hospital do Coração-Hcor, Brazil Correspondence: Marcio de Castro Ferreira, Department of Ortopedics, Hospital do Coração-Hcor, Brazil, Tel 30536611, Email marciojoelho@gmail.com Received: October 11, 2017 | Published: December 20, 2017 Abstract The authors report a case of knee trauma in a 24-year-old woman. The X-ray showed a Segond’s fracture: an avulsed bone fragment, lying immediately below the joint line of the lateral tibial plateau, dislocated a few millimeters from the lateral tibial cortex. The fracture site was related to the site of anterolateral ligament (ALL) and iliotibial band (ITB) tibial attachment. Clinical examination revealed anterolateral instability of the knee. Magnetic resonance image (MRI) and subsequent arthroscopy revealed an isolated ALL lesion. All other strictures were intact: anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), postero-lateral corner (PLC) and meniscus. The author reports an isolated Segond fracture in adult. Keywords: segond fracture, anterolateral ligament, knee, avulsion fracture MOJ Sports Medicine Case Report Open Access