The iliotibial band in acute knee trauma: patterns of injury on MR imaging.

Abstract

To delineate the spectrum of knee injuries associated with sprains and tears of the distal iliotibial band (ITB). A retrospective review of 200 random MRI scans undertaken for acute knee trauma was performed. Scans were excluded if there was a history of injury over 4 weeks from the time of the scan, septic arthritis, inflammatory arthropathy, previous knee surgery, or significant artefact. In each scan, the ITB was scored as normal, minor sprain (grade 1), severe sprain (grade 2), and torn (grade 3). The menisci, ligaments, and tendons of each knee were also assessed. The mean age was 27.4 years (range, 9-69 years) and 71.5% (n = 143) of the patients were male. The ITB was injured in 115 cases (57.5%). The next most common soft tissue structure injured was the anterior cruciate ligament (ACL) in 53.5% of cases (n = 107). Grade 1 ITB injury was seen in 90 of these 115 cases (45%), grade 2 injury in 20 cases, and grade 3 injury in only five cases. There is a significant association between ITB injury and ACL rupture (p < 0.05), as well as acute patellar dislocation (p < 0.05). There were ten cases of significant posterolateral corner injury, and all were associated with ITB injury, including four ITB tears. Only two cases of isolated ITB injury were seen (1%). ITB injury is common in acute knee trauma and is associated with significant internal derangement of the knee, especially cruciate ligament rupture, posterolateral corner injury, and patellar dislocation.