Contributions of Lower-Limb Muscle Power in Gait of People Without Impairments

Abstract

Background and Purpose. Although gait asymmetry in rehabilitation has been documented, little is known about propulsion and control tasks performed by each limb and how these tasks are managed between the lower limbs. The purpose of this study was to test the hypothesis that the leading limb contributes mainly to forward progression, whereas the trailing limb provides control and propels the lower limb to a lesser extent. Subjects. Nineteen men with an average age of 26.2 years (SDϭ3.2, rangeϭ21-34) and no history of orthopedic ailments participated in the study. Methods. Muscle power was determined using an 8-camera high-speed video system synchronized with 2 force plates. The principal-component analysis method was applied to reduce and classify 52 gait variables for each limb, and Pearson correlations were used to determine the interactions within the data sets for each limb. Results. Gait propulsion was initiated by the hip of the leading limb shortly after heel-strike and was maintained throughout the stance phase. Control was the main task of the trailing limb, as evidenced by the power absorption bursts at the hip and knee. Conclusion and Discussion. Within-limb interaction further emphasized the functional relationship between forward progression and control tasks and highlighted the importance of frontal-and transverse-plane actions during gait. [Sadeghi H, Allard P, Duhaime M. Contributions of lower-limb muscle power in gait of people without impairments. Phys Ther.

Vaulting quantification during level walking of transfemoral amputees

“…On the contrary, ankle flexion power appears to be a reliable parameter for vaulting quantification. This parameter is directly linked to the concentric work of muscles of the contralateral ankle (Sadeghi et al, 2000). Furthermore, all amputees presenting vaulting showed ankle flexion power values higher than 0.15 W•kg −1 whereas values below 0.1 W•kg − 1 were observed for other amputees (Fig.…”

Plantarflexion moment is a contributor to step length after-effect following walking on a split-belt treadmill in individuals with stroke and healthy individuals

“…for this subgroup, it is possible that paretic hip flexors were not able to compensate for the weak push-off (11). Other authors showed that hip extensors were also important in the control of step length in healthy individuals (12)(13). Consequently, analyzing joint moments following gait sessions on a split belt-treadmill might help to explain the reduction of step length asymmetry and confirm whether this approach could be used to train paretic lower limb muscles.…”

“…Characteristics of participants post-stroke with the level of significance set at 0.05, except for those corrected for the number of comparisons.The mean and standard deviation (SD) for age, height and body mass of healthy participants were 57.6 years (SD 17.2), 1.7 m (SD 0.1), and 70.7 kg (SD 14.6), respectively. healthy individuals scored in the normal range for all sensory assessments(13,23,(26)(27)(28) and all scored 56/56 on the berg balance Scale. Their mean comfortable and baseline gait speeds on the treadmill were 1.26 m/s (SD 0.15) and 0.88 m/s (SD 0.1).Table Ipresents the characteristics of participants post-stroke.…”

Peer Review #1 of "An investigation into the bilateral functional differences of the lower limb muscles in standing and walking (v0.1)"

“…The right limb is mainly used to provide propulsion while the key role of left limb is to maintain stability of the body and slightly contribute to the propulsion (Hirokawa, 1989;Sadeghi, 2001). Bilateral lower extremities would exhibit different patterns of the complex movement, and this will result into difference in each muscle between left limb and right limb.…”