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Published on: January 17, 2013
The effect of trunk flexion on able-bodied gait
Devjani Saha1, Steven Gard, Stefania Fatone
1Northwestern University Prosthetics Research Laboratory & Rehabilitation Engineering Research Program, Chicago, IL 60611, United States. d-saha@northwestern.edu
Gait & Posture
|October 9, 2007
Summary
Altered trunk posture significantly impacts gait by causing lower limb kinematic changes to maintain balance. These adaptations affect the body's center of mass trajectory and vertical ground reaction forces during walking.
Area of Science:
- Biomechanics
- Human Movement Science
- Clinical Biomechanics
Background:
- Trunk posture alterations are common with aging and spinal conditions like lumbar flatback.
- Understanding gait changes associated with trunk posture is clinically relevant for patient management.
Purpose of the Study:
- To investigate the effects of sagittal trunk flexion on gait kinematics and kinetics in able-bodied adults.
- To analyze compensatory mechanisms during trunk-flexed walking.
Main Methods:
- Gait analysis of 14 adults at various speeds (slow, normal, fast).
- Subjects maintained three trunk postures: upright, 25° flexion, and 50° flexion.
- Kinematic data of lower limb joints and body center of mass (BCOM) were recorded.
Main Results:
- Trunk flexion induced a crouch posture with sustained knee flexion and increased hip/ankle flexion.
- Kinematic adaptations shifted the trunk and pelvis posteriorly to counterbalance trunk mass.
- Altered joint kinematics resulted in a phase lag in BCOM position, velocity, and acceleration, affecting vertical ground reaction forces (GRF(v)).
Conclusions:
- Kinematic adaptations during trunk-flexed gait help maintain dynamic balance by modifying BCOM trajectory.
- Changes in BCOM dynamics are reflected in altered GRF(v).
- Findings offer insights into compensatory strategies in individuals with trunk-flexed postures.
