Age-related differences in sagittal-plane knee function at heel-strike of walking are increased in osteoarthritic patients

Abstract

Objective. To compare age-related patterns of gait with patterns associated with knee osteoarthritis (OA), the following hypotheses were tested: H1) The sagittal-plane knee function during walking is different between younger and older asymptomatic subjects; H2) The age-related differences in H1 are increased in patients with knee OA. Design. Walking trials were collected for 110 participants (1.70 ± 0.09 m, 80 ± 14 kg). There were 29 younger asymptomatic subjects (29 ± 4 years) and 81 older participants (59 ± 9 years), that included 27 asymptomatic subjects and 28 and 26 patients with moderate and severe medial knee OA. Discrete variables characterizing sagittal-plane knee function were compared among the four groups using ANOVAs. Results. During the heel-strike portion of the gait the cycle at preferred walking speed, the knee was less extended and the shank less inclined in the three older groups compared to the younger asymptomatic group. There were similar differences between the severe OA group and the older asymptomatic and moderate OA groups. Both OA groups also had the femur less posterior relative to the tibia and smaller extension moment than the younger group. During terminal stance, the severe OA group had the knee less extended and smaller knee extension moment than the younger asymptomatic and older moderate OA groups. Conclusions. The differences in knee function, particularly those during heel-strike which were associated with both age and disease severity, could form a basis for looking at mechanical risk factors for initiation and progression of knee OA on a prospective basis.

Alterations in Knee Kinematics After Partial Medial Meniscectomy Are Activity Dependent

“…8,18 The kinematic differences seen in this study are consistent with other OA at-risk populations: Greater external rotation is seen in the operated limb after ACL reconstruction, 34 and increased flexion angle at initial contact is shown in the ACL-reconstructed population 35 and the aging population. 19 The greater kinematic limb differences seen during more demanding activities with greater knee loading illustrate the importance of investigating activities of daily living in addition to gait and suggest that the kinematic limb differences found here are likely present during more strenuous activities such as running or playing sports. Seeing that these gait alterations are present during dynamic but not static activities suggests both a structural and a possible muscular component to the changes seen after partial meniscectomy.…”

“…25 Alterations in initial contact flexion angle alter cartilage loading, potentially damaging the cartilage and initiating degenerative joint changes. 8 Similar sagittal plane kinematic differences close to initial contact (beginning of stance) have been documented in subjects who have had anterior cruciate ligament (ACL) reconstruction, 35 in older individuals, 19 and in subjects with tibiofemoral knee OA, 19 thus marking sagittal plane kinematics as important in the study of joint degeneration. Furthermore, alterations to sagittal plane kinematics could suggest strength and muscular differences as the knee is controlled by knee extensors and flexors in this plane.…”

“…The primary outcomes analyzed were average tibia external rotation angle with respect to the femur during the stance phase 33 and the knee flexion angle at initial contact 6,19,25 (when the foot first contacts the floor or stair).…”

A Systems View of Risk Factors for Knee Osteoarthritis Reveals Insights into the Pathogenesis of the Disease

“…A recent study 20 summarized several critical ambulatory changes that occur with aging and identified significant differences in sagittal plane knee kinematics between a healthy younger population (29±4 yrs) and a healthy older population (59±9 yrs). Kinematic differences were observed at heel strike with significantly less knee extension (Figure 5a), less posterior femoral displacement, and less backward shank inclination in the older healthy population as compared to the younger population.…”

Functional imaging in OA: role of imaging in the evaluation of tissue biomechanics

“…Gross differences in gait patterns due to OA severity are well documented [57, 72–74]. While the analysis of gait is not strictly a functional imaging method focused on a specific tissue, is reasonable to expect that imaging-assessed gait in patients with moderate or severe OA would differ from asymptomatic individuals due to the likely increase in pain or joint structural alterations that would manifest in macroscopic, whole-body changes.…”