Variation of hamstrings lengths and velocities with walking speed

Abstract

Crouch gait, one of the most prevalent movement abnormalities among children with cerebral palsy, is frequently treated with surgical lengthening of the hamstrings. To assist in surgical planning many clinical centers use musculoskeletal modeling to help determine if a patient's hamstrings are shorter or lengthen more slowly than during unimpaired gait. However, some subjects with crouch gait walk slowly, and gait speed may affect peak hamstring lengths and lengthening velocities. The purpose of this study was to evaluate the effects of walking speed on hamstrings lengths and velocities in a group of unimpaired subjects over a large range of speeds and to determine if evaluating subjects with crouch gait using speed matched controls alters subjects' characterization as having “short” or “slow” hamstrings. We examined 39 unimpaired subjects who walked at five different speeds. These subjects served as speed-matched controls for comparison to 74 subjects with cerebral palsy who walked in crouch gait. Our analysis revealed that peak hamstrings length and peak lengthening velocity in unimpaired subjects increased significantly with increasing walking speed. Fewer subjects with cerebral palsy were categorized as having hamstrings that were “short” (31/74) or “slow” (38/74) using a speed-matched control protocol compared to a non-speed-matched protocol (35/74 “short”, 47/74 “slow”). Evaluation of patients with cerebral palsy using speed-matched controls alters and may improve selection of patients for hamstrings lengthening procedures.

Hamstring and psoas length of crouch gait in cerebral palsy: a comparison with induced crouch gait in age- and sex-matched controls

“…Previous studies showed increases in peak hamstring length with increasing walking speed [25,26]. In this study, walking speed in mimicked crouch gait was significantly faster than that in patients with crouch gait (p<0.001).…”

Mid‐term development of hamstring tendon length and velocity after distal femoral extension osteotomy in children with bilateral cerebral palsy: a retrospective cohort study

“…4,5 Satisfying short-term results were complemented with reports of increased pelvic tilt and genu recurvatum as signs of overcorrection. 8,9 Furthermore, recurrent hamstring tightness during growth is one reason considered for the recurrence of flexed knee gait. 1 Musculoskeletal analysis revealed that only one-third of the hamstrings in children with flexed knee gait are short and slow.…”

Lower limb loading during knee up in step aerobics: a pilot study

“…Therefore, they have greater efficiency and are used for activities that need strength [2,33]. A review of the literature has shown that few studies [1,8,17,20,29] go beyond a description of muscle length changing during a crouching gait, and no references were found in sport application and above all in knee up move analysis.…”