How Crouch Gait Can Dynamically Induce Stiff-Knee Gait

Title

Author

Van der Krogt, M.M.
Bregman, D.J.J.
Wisse, M.
Doorenbosch, C.A.M.
Harlaar, J.
Collins, S.H.

Faculty

Mechanical, Maritime and Materials Engineering

Department

Biomechanical Engineering

Abstract

Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on excessive knee muscle activity during (pre)swing, but the passive dynamics of the limbs may also have an important effect. To examine the effects of a crouched posture on swing knee flexion, we developed a forwarddynamic model of human walking with a passive swing knee, capable of stable cyclic walking for a range of stance knee crouch angles. As crouch angle during stance was increased, the knee naturally flexed much less during swing, resulting in a ‘stiff-knee’ gait pattern and reduced foot clearance. Reduced swing knee flexion was primarily due to altered gravitational moments around the joints during initial swing. We also considered the effects of increased push-off strength and swing hip flexion torque, which both increased swing knee flexion, but the effect of crouch angle was dominant. These findings demonstrate that decreased knee flexion during swing can occur purely as the dynamical result of crouch, rather than from altered muscle function or pathoneurological control alone.

Subject

Human
Walking
Biomechanics
Rehabilitation
Orthopedics, Cerebral palsy
Passive dynamics, Mathematical model
Simulation

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http://resolver.tudelft.nl/uuid:d9d6078f-690b-4a69-88c1-8b8d0e205d2c

DOI

https://doi.org/10.1007/s10439-010-9952-2

Publisher

Springer

ISSN

0090-6964

Source

Annals of Biomedical Engineering, 38 (4), 2010