Atraumatic lateral collateral ligament complex signal abnormalities by magnetic resonance imaging in patients with osteoarthrosis of the knee

OBJECTIVES:: To determine the prevalence of atraumatic lateral collateral ligament complex (LCLC) abnormalities by magnetic resonance imaging (MRI) in patients with osteoarthrosis (OA) of the knee. METHODS:: Magnetic resonance imaging scans in 96 subjects (25 with OA and 71 without OA) were retrospectively reviewed for the presence and severity of LCLC signal abnormalities. Abnormalities in the MRI scans of subjects with OA were compared with those of subjects without OA using X² test and the Mantel-Haenszel test for trend. RESULTS:: Lateral compartment OA (23 of 25) was associated with abnormalities of the LCLC in 96% (22 of 23 subjects had fibular collateral ligament abnormalities, P < 0.0001). Medial compartment OA (25 of 25) was associated with abnormalities of the LCLC in 88% (22 of 25 subjects had fibular collateral ligament abnormalities, P < 0.0001). There was a positive trend for severity of MRI abnormalities with severity of OA (P < 0.0001 to P ≤ 0.04). CONCLUSIONS:: Lateral collateral ligament complex MRI signal abnormalities are common in patients with OA, in the absence of trauma.