Varus thrust and knee frontal plane dynamic motion in persons with knee osteoarthritis

Abstract

Objective Varus thrust visualized during walking is associated with a greater medial knee and an increased risk of medial knee osteoarthritis (OA) progression. Little is known about varus thrust presence determined by visual observation relates to quantitative gait kinematic We hypothesized that varus thrust presence is associated with greater knee frontal plane dynamic movement during the stance phase of gait. Methods Participants had knee OA in at least one knee. Trained examiners assessed participants for varus thrust presence during ambulation. Frontal plane knee motion during ambulation captured using external passive reflective markers and an 8-camera motion analysis system. To examine the cross-sectional relationship between varus thrust and frontal plane knee motion, used multivariable regression models with the quantitative motion measures as dependent variables and varus thrust (present/absent) as predictor; models were adjusted for age, gender, BMI, gait speed, and knee static alignment. Results 236 persons [mean BMI: 28.5 kg/m2 (SD 5.5), mean age: 64.9 years (SD 10.4), 75.8% women] contributing 440 knees comprised the study sample. 82 knees (18.6%) had definite varus thrust. Knees with varus thrust had greater peak varus angle and greater peak varus angular velocity during stance than knees without varus thrust (mean differences 0.90° and 6.65°/sec, respectively). These patterns remained significant after adjusting for age, gender, BMI, gait speed, and knee static alignment. Conclusion Visualized varus thrust during walking was associated with a greater peak knee varus angular velocity and a greater peak knee varus angle during stance phase of gait.

Gait knee kinematic alterations in medial osteoarthritis: three dimensional assessment

“…Results of this study revealed that knee OA patients showed a significantly increased knee adduction angle throughout the gait cycle. These data are consistent with the findings of previous studies [4,10,12]. This frontal instability associated with increased adduction angle may increase further degradation of the cartilage.…”

“…Quantitative kinematic analysis is an important tool for a thorough understanding of joint function [1]. Kinematics of osteoarthritic (OA) knees has been evaluated using surgical navigation systems, magnetic resonance imaging (MRI) and computed tomography (CT) [2][3][4], but these techniques cannot be used to study weight-bearing activities, and their results may be therefore be affected. With advances in sophisticated motion-capture technology, 3D knee motion during weightbearing is now available.…”

Frontal plane knee mechanics and medial cartilage MR relaxation times in individuals with ACL reconstruction: A pilot study

“…4–6 It has been hypothesized that abnormal gait mechanics may contribute to altered cartilage loading and subsequent PTOA following an ACL-R. 7 Specifically, higher external knee adduction moment (KAM) and dynamic knee varus during walking have been implicated in the pathogenesis of knee OA. 8–11 These metrics, along with static varus deformity, 12 are associated with an increase in frontal plane knee loading predisposing the medial knee cartilage to greater loading and subsequent degeneration. 8, 13, 14 Furthermore, abnormal movement patterns for the reconstructed knee have also been demonstrated for other activities including running, 4 stair climbing, 5, 7 and drop landing.…”

Varus Thrust and Incident and Progressive Knee Osteoarthritis

“…19 Notably, the difference in angular velocity (which captures both movement direction and speed) between knees with and without varus thrust was unaffected by adjustment for alignment, while the difference in peak knee varus angle was in part explained by alignment. 19 In another study, in women with medial knee OA, the knee adduction angle during gait and shank mean angular velocity were greater from heel strike to 30% stance in the OA group vs. controls, and were associated with maximum KAM. 20 Mahmoudian et al found that varus thrust (measured as knee varus angle increase during the weight-bearing phase of gait) was greater in both early and established OA groups vs. controls suggesting problems with stabilization in early knee OA.…”