Empirical assessment of dynamic hamstring function during human walking. J Biomech 2013 Apr 26;46(7):1255-61
Date
04/02/2013Pubmed ID
23540723Pubmed Central ID
PMC3645289DOI
10.1016/j.jbiomech.2013.02.019Scopus ID
2-s2.0-84876342914 (requires institutional sign-in at Scopus site) 9 CitationsAbstract
The hamstrings are often associated with the development of crouch gait, a fatiguing form of walking characterized by excessive hip flexion, knee flexion and ankle dorsiflexion during stance. However, recent studies have called into question whether abnormally active hamstrings induce the limb to move into a crouch posture. The purpose of this study was to directly measure the influence of the hamstrings on limb posture during stance. Nineteen healthy young adults walked on an instrumented treadmill at their preferred speed. A 90 ms pulse train was used to stimulate the medial hamstrings during either terminal swing or loading response of random gait cycles. Induced motion was defined as the difference in joint angle trajectories between stimulated and non-stimulated strides. A dynamic musculoskeletal simulation of normal gait was generated and similarly perturbed by increasing hamstring excitation. The experiments show that hamstring stimulation induced a significant increase in posterior pelvic tilt, knee flexion and ankle dorsiflexion during stance, while having relatively less influence on the hip angular trajectory. The induced motion patterns were similar whether the hamstrings were stimulated during late swing or early stance, and were generally consistent with the direction of induced motion predicted by gait simulation models. Hence, we conclude that overactive hamstrings have the potential to induce the limb to move toward a crouch gait posture.
Author List
Thelen DG, Lenz AL, Francis C, Lenhart RL, Hernández AAuthor
Rachel L. Lenhart MD Assistant Professor in the Orthopaedic Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultComputer Simulation
Female
Gait
Humans
Lower Extremity
Male
Models, Biological
Walking
