Lower limb torsional malalignment is associated with pain in individuals with medial compartment knee osteoarthritis

Abstract

injury (i.e., knee injury occurred in the past 12 months that was severe enough to limit the ability to walk for at least two days). Since the temporal sequence between KEs and SBCs was unclear, we also performed additional analyses adjusting for each other in the multivariable regression model. Subjects who had a TKR or had missing values for variables of interest in either knee were excluded. Results: We included 888 subjects with knees discordant for pain at rest and 253 with knees discordant for pain exacerbation with walking measured by NRS. For pain in bed, pain with sitting/lying down and pain with walking assessed using WOMAC pain sub-scales, 688, 780 and 1239 subjects were identified as having discordant knees, respectively. Approximately 60% of participants included in the analyses were women, the mean age ranged between 62.1 and 63.4 years, and mean BMI was from 29.1 to 29.6 kg/m 2 . When knee pain at rest and pain exacerbation with walking were measured by NRS in the walking test, the adjusted odds ratios (OR) for the association of KEs with pain at rest and pain exacerbation with walking were 1.8 (95% confidence interval (CI): 1.3-2.5) and 3.7 (1.8-7.8), respectively. The corresponding ORs for SBCs were 1.1 (0.7-1.7) and 2.1 (1.1-4.3), respectively (Table 1). Similar differential associations of KEs and SBCs with pain at rest and pain with walking assessed by WOMAC pain sub-scales were also observed ( Table 2). When we further adjusted for SBCs in the multivariable regression model for KEs, or vice versa, the results did not change significantly. Conclusions: Both knee effusions and subchondral bone cysts contributed to pain with walking, whereas only knee effusions were associated with pain at rest.