title: Injury patterns to the posteromedial corner of the knee in high-grade multiligament knee injuries: a MRI study.
abstract: Injury patterns to the posteromedial corner of the knee have not been previously studied in the context of multiligament knee injuries. We performed a retrospective magnetic resonance imaging and clinical review of a consecutive series of 27 dislocatable knees presenting to a single level-one trauma center from 2005 to 2008. Post-injury magnetic resonance imaging studies were reviewed by two fellowship-trained musculoskeletal radiologists to assess injury patterns to the posteromedial corner. In our series, injury to at least one structure within the posteromedial corner was observed in 81% (22/27) of cases while injury to the superficial medial collateral ligament alone was seen in 63% (17/27) of cases. Furthermore, injuries to the posterior horn of the medial meniscus were associated with a tear of the meniscotibial ligaments in all cases and with a tear of the posterior oblique ligament in 67% of cases. All patients with grade III laxity (>10 mm medial opening) under an examination under anesthesia had a complete tear of the posterior oblique ligament and meniscotibial ligament in addition to a medial collateral ligament injury. Injury to the semimembranosus attachment alone was not associated with clinically significant laxity under an examination under anesthesia. Our findings demonstrate that injuries to the posteromedial corner are common in the setting of traumatic knee dislocations. Interestingly, high-grade medial instability during an examination under anesthesia and injury to the posterior horn of the medial meniscus may be important indicators for further posteromedial corner injury.
authors.affiliation: University of Toronto, 4410-763 Bay Street, Toronto, ON, M5G 2R3, Canada. jaschahal@hotmail.com
authors.forename: Jaskarndip
authors.initials: J
authors.lastname: Chahal
authors.forename: Muhyeddine
authors.initials: M
authors.lastname: Al-Taki
authors.forename: Dawn
authors.initials: D
authors.lastname: Pearce
authors.forename: Anthea
authors.initials: A
authors.lastname: Leibenberg
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Whelan
mesh_terms: D000293:Adolescent; D000328:Adult; D004487:Edema / Q000209:etiology; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D007593:Joint Instability / Q000145:classification / Q000209:etiology / Q000628:therapy; D031221:Knee Dislocation / Q000209:etiology; D007718:Knee Injuries / Q000473:pathology* / Q000628:therapy; D008023:Ligaments, Articular / Q000293:injuries* / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult