Leg stiffness during running in adults with traumatic brain injury: A comparative study with healthy adults

Abstract

Background: While leg stiffness during running has been shown to be lower in children with cerebral palsy compared to their typically developing peers, no studies have examined leg stiffness during running in adults with traumatic brain injury. The aim of this study was to compare leg stiffness during running in adults with traumatic brain injury to healthy controls.

Methods: Sixty-one adults with traumatic brain injury and 20 healthy controls were included. Participants ran overground while three-dimensional kinematic and kinetic data were recorded. Leg stiffness was calculated during the stance phase of running. Statistical analyses to compare leg stiffness between limbs and between groups were conducted using t-tests.

Findings: There was a large range of leg stiffness in adults with traumatic brain injury during running (affected leg median = 21.56 [range 11.07 to 57.44] kN/m; less affected leg =20.87 [9.38 to 54.72] kN/m) compared to healthy controls (20.94 [13.40 to 31.50] kN/m). However, there were no statistically significant differences in leg stiffness during running between the affected and less affected limbs (p = 0.59, effect size [ES] =0.08) nor between both traumatic brain injury limbs and healthy controls (affected limb; p = 0.44, ES =0.12; less affected limb; p = 0.47, ES =0.11).

Interpretation: Although no statistical significance was found on a group level, the results demonstrated high variability in leg stiffness in traumatic brain injury compared to healthy controls. Further research is needed to determine which factors influence leg stiffness during running and how this measure relates to clinical outcomes in traumatic brain injury.

Keywords: Biomechanics; Gait analysis; Kinetics; Rehabilitation; Running; Traumatic brain injury.