Dataset Information

'Whip from the hip': thigh angular motion, ground contact mechanics, and running speed.

ABSTRACT: During high-speed running, lower limb vertical velocity at touchdown has been cited as a critical factor needed to generate large vertical forces. Additionally, greater leg angular velocity has also been correlated with increased running speeds. However, the association between these factors has not been comprehensively investigated across faster running speeds. Therefore, this investigation aimed to evaluate the relationship between running speed, thigh angular motion and vertical force determinants. It was hypothesized that thigh angular velocity would demonstrate a positive linear relationship with both running speed and lower limb vertical velocity at touchdown. A total of 40 subjects (20 males, 20 females) from various athletic backgrounds volunteered and completed 40?m running trials across a range of sub-maximal and maximal running speeds during one test session. Linear and angular kinematic data were collected from 31-39?m. The results supported the hypotheses, as across all subjects and trials (range of speeds: 3.1-10.0?m?s-1), measures of thigh angular velocity demonstrated a strong positive linear correlation to speed (all R 2>0.70, P<0.0001) and lower limb vertical velocity at touchdown (all R 2=0.75, P<0.001). These findings suggest thigh angular velocity is strongly related to running speed and lower limb impact kinematics associated with vertical force application.

SUBMITTER: Clark KP

PROVIDER: S-EPMC7595692 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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'Whip from the hip': thigh angular motion, ground contact mechanics, and running speed.

Clark Kenneth P KP Meng Christopher R CR Stearne David J DJ

Biology open 20201021 10

During high-speed running, lower limb vertical velocity at touchdown has been cited as a critical factor needed to generate large vertical forces. Additionally, greater leg angular velocity has also been correlated with increased running speeds. However, the association between these factors has not been comprehensively investigated across faster running speeds. Therefore, this investigation aimed to evaluate the relationship between running speed, thigh angular motion and vertical force determi ...[more]

PMID: 32917763

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Project description:PurposeTo determine whether inclusion of the acetabular labrum affects the maximum range of motion (ROM) during simulation of the flexion-adduction-internal rotation impingement examination.MethodsThree-dimensional surface reconstructions of the femur, hemi-pelvis, and labrum from computed tomography arthrography images of 19 participants were used to simulate maximum ROM during the flexion-adduction-internal rotation examination. Simulations were conducted for positions between 70° and 110° flexion and 0° and 20° adduction at 10° increments to measure maximum internal rotation and the position of contact between the femur and acetabular rim (bone-to-bone) or the femur and labrum (bone-to-labrum). Internal rotation angles and clock-face position values were compared between the 2 contact scenarios for each position.ResultsThe ROM in the bone-to-labrum contact model was significantly less than that of the bone-to-bone contact model for all evaluated positions (P ≤ .001, except at 110° flexion and 20° adduction, P = .114). The inclusion of the labrum reduced internal rotation by a median [interquartile range] of 18 [15, 25]° while altering the position of contact on the acetabular clock-face by -0:01 [-0:27, 0:16]. The variability in contact location for the bone-to-labrum contact scenario was nearly double that of the bone-to-bone contact scenario, as indicated by the interquartile range.ConclusionsInclusion of the anatomy of the acetabular labrum in collision models used to simulate impingement examinations reduced the internal rotation ROM by approximately 20° and increased variability in the location of contact relative to the acetabular rim.Clinical relevanceWhile standard bone-to-bone contact ROM simulations may be informative with respect to the relative change in ROM based on a surgical intervention (e.g., pre- and post-osteochondroplasty for cam-type femoroacetabular impingement), they may not accurately represent the clinical ROM of the joint or the kinematic position at which damage may occur due to shape mismatch between the femur and acetabulum.

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Dataset Information

'Whip from the hip': thigh angular motion, ground contact mechanics, and running speed.

Publications

'Whip from the hip': thigh angular motion, ground contact mechanics, and running speed.

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