Gait evaluation in hip osteoarthritic and normal dogs using a serial force plate system

Abstract

SummaryThe effect of canine hip osteoarthritis (OA) on vertical force distribution was studied using a serial force platform system. This system allows simultaneous measurement of vertical and horizontal force impulses from each limb of a trotting dog. Using these measurements and novel analysis techniques a complete and precise analysis of load distribution was performed. Load distribution was compared between a group of normal dogs and a group of dogs with radiographic evidence of hip OA. Results of this study indicate that trotting dogs with hip OA redistribute vertical force primarily by shifting force between trotting pairs (side-to-side compensation) rather than within trotting pairs (hind-to-fore compensation).

Intra-articular anaesthesia mitigates established pain in experimental osteoarthritis: a preliminary study of gait impulse redistribution as a biomarker of analgesia pharmacodynamics

“…Hence, alterations in gait and joint loading patterns have long been targeted by researchers as a means to noninvasively monitor the pathogenesis of OA (particularly in animal models) and as an index of chronic joint pain 23,24 . The present studies, though preliminary in nature due to the limited number of animals investigated and range of conditions analyzed, support the assertion of Bertram et al 8 and Kennedy et al 10 that the Impulse Ratio can be used as a relatively sensitive and timeeffective method of monitoring the relative load support of each limb to carry the body mass of trotting quadrupeds. Impulse Ratio is a measure of gait directly related to the functional capabilities of the animal and differs substantially from other kinetic analyses that utilize ground-reaction force derived from less than a full stride cycle.…”

“…Vertical ground-reaction force (and apparent applied impulse) is sensitive to small horizontal accelerations (positive or negative 9,13 ). The Impulse Ratio analysis of Lee et al 9 accounted for these accelerations by calculating the torque applied by the horizontal component of the force to the centre-of-mass of the animal over the stride cycle and normalized the impulse distribution to steadystate (constant speed 8,10 ). This provides a substantial increase in analysis precision 9 and facilitates the characterization of gait because acceleration over the force-platform array need not be controlled or restricted (indeed, runs involving horizontal acceleration actually improve the precision of impulse distribution characterization for steady-state locomotion 9 ).…”

Correlation of Surface Electromyography of the Vastus Lateralis Muscle in Dogs at a Walk with Joint Kinematics and Ground Reaction Forces

“…NUMEROUS METHODS have been used in canine motion analysis to describe normal and abnormal gait. Besides visual evaluation of lameness, measurement of ground reaction forces (GRF) and joint kinematics in physiologic 1–4 and pathologic 5–9 conditions demonstrate that orthopedic disorders cause complex biomechanical changes in limb function. To gain deeper understanding of canine locomotion, it is essential to have knowledge of dynamic skeletal muscle function.…”

Precision and Accuracy of Ground Reaction Force Normalization in a Heterogeneous Population of Dogs

“…Asymmetry between right and left outside of this range indicates a pathologic gait and return to symmetry indicates resolution of lameness . It has been established that the contralateral limb cannot be used as an internal control for evaluation of lameness when using pure GRF, because weight‐bearing is transferred to the contralateral limb . However, with established SI from a normal population of dogs, the effect of surgical treatment can be quantified by calculating the SI postoperatively, then monitoring improvement of the index and loss of asymmetry with time.…”

“…26 It has been established that the contralateral limb cannot be used as an internal control for evaluation of lameness when using pure GRF, because weight-bearing is transferred to the contralateral limb. 14,29 However, with established SI from a normal population of dogs, the effect of surgical treatment can be quantified by calculating the SI postoperatively, then monitoring improvement of the index and loss of asymmetry with time. If the treatment is successful, the patient should attain the SI of a normal population.…”