Lower Limb Kinematics in Individuals with Hip Osteoarthritis during Gait: A Focus on Adaptative Strategies and Interlimb Symmetry

Abstract

Among the functional limitations associated with hip osteoarthritis (OA), the alteration of gait capabilities represents one of the most invalidating as it may seriously compromise the quality of life of the affected individual. The use of quantitative techniques for human movement analysis has been found valuable in providing accurate and objective measures of kinematics and kinetics of gait in individuals with hip OA, but few studies have reported in-depth analyses of lower limb joint kinematics during gait and, in particular, there is a scarcity of data on interlimb symmetry. Such aspects were investigated in the present study which tested 11 individuals with hip OA (mean age 68.3 years) and 11 healthy controls age- and sex-matched, using 3D computerized gait analysis to perform point-by-point comparisons of the joint angle trends of hip, knee, and ankle. Angle-angle diagrams (cyclograms) were also built to compute several parameters (i.e., cyclogram area and orientation and Trend Symmetry) from which to assess the degree of interlimb symmetry. The results show that individuals with hip OA exhibit peculiar gait patterns characterized by severe modifications of the physiologic trend at hip level even in the unaffected limb (especially during the stance phase), as well as minor (although significant) alterations at knee and ankle level. The symmetry analysis also revealed that the effect of the disease in terms of interlimb coordination is present at knee joint as well as hip, while the ankle joint appears relatively preserved from specific negative effects from this point of view. The availability of data on such kinematic adaptations may be useful in supporting the design of specific rehabilitative strategies during both preoperative and postoperative periods.

Keywords: gait; hip osteoarthritis (OA); kinematics; symmetry.

Figure 1

Experimental setup. The optoelectronic motion capture system is composed of 8 infrared cameras set at 120 Hz frequency, two RGB cameras for documentation purposes, and a workstation to collect, integrate and analyze data.

Figure 2

Graphic representation of markers placement according to the protocol proposed by Davis et al. [17].

Figure 3

Graphic representation of a cyclogram and its main features considered for the present study.

Figure 4

Box plot summarizing the values of GPS for each group considered. The green line represents the control group, the blue line represents the unaffected limb of individuals with OA, and the red line represents the affected limb of individuals with OA.

Figure 5

Box plots summarizing the dynamic ROM for hip, knee, and ankle joints. The green line represents the control group, the blue line represents the unaffected limb of individuals with OA, and the red line represents the affected limb of individuals with OA.

Figure 6

Gait kinematics in the sagittal plane. From top to bottom: hip flexion-extension, knee flexion-extension, and ankle dorsi-plantar-flexion angles during gait cycle. From left to right: comparison between the affected and unaffected limbs in people with OA, comparison between the affected limb of people with OA and healthy controls, comparison between the unaffected limb of people with OA and healthy controls. The grey-shaded areas denote the periods of the gait cycle in which a significant difference between the groups existed (p < 0.05).

Figure 7

Example of cyclograms for individuals with hip OA and healthy controls.

Figure 8

Box plots summarizing Area, Orientation, and Trend Symmetry for hip, knee, and ankle joints. The green line represents the control group and the red line individuals with OA.