Results from this study indicated patients with non-traumatic knee osteoarthritis were different from patients with post-traumatic knee osteoarthritis in regard to knee adduction angles and kinematics during ambulation.
by Monica Jaramillo, Healio Rheumatology, August 26, 2016
Researchers classified patients with medial knee osteoarthritis (OA) as either non-traumatic (n=122) or post-traumatic (n=93) based on arthroscopic confirmation for evidence of a previous ACL tear. Researchers also conducted a post hoc analysis with patients who had an ACL tear, but no knee OA. Investigators used radiographs to determine Kellgren/Lawrence severity scores and the mechanical axis angle (MAA).
Gait analysis was used to calculate the knee flexion, adduction angles and external moments. Waveform characteristics were determined with principal component (PC) analysis, and peak values were identified. The OA groups were examined on whether they predicted peak values and PC scores after investigators controlled for age, gait speed and severity with linear regression models. Investigators then repeated the models with and without controlling for the MAA.
Results showed a significant predictor for peak knee adduction angles and moments was the knee OA group. Investigators noted the knee OA group was also a significant predictor for some knee adduction angle and moment PC scores. The non-traumatic OA group compared with the post-traumatic group had higher adduction angles and moments. According to researchers, the only significant association was between the knee adduction moment shape characteristics and the OA group after results were controlled for MAA.
Source Healio Rheumatology
Comparison of Gait Characteristics Between Patients With Nontraumatic and Posttraumatic Medial Knee Osteoarthritis, Robbins SM, Birmingham TB, Jones IC, Sischek EL, Dietzsch M, Giffin JR. Arthritis Care Res (Hoboken). 2016 Sep;68(9):1215-23. doi: 10.1002/acr.22822. Epub 2016 Jul 27.