Associations between Muscle Strength Asymmetry and Impairments in Gait and Posture in Young Brain-Injured Patients

Abstract

Traumatic brain injury (TBI) can lead to deficits in gait and posture, which are often asymmetric. A possible factor mediating these deficits may be asymmetry in strength of the leg muscles. However, muscle strength in the lower extremities has rarely been investigated in (young) TBI patients. Here, we investigated associations between lower-extremity muscle weakness, strength asymmetry, and impairments in gait and posture in young TBI patients. A group of young patients with moderate-to-severe TBI (n=19; age, 14 years 11 months ±2 years) and a group of typically developing subjects (n=31; age, 14 years 1 month±3 years) participated in this study. A force platform was used to measure postural sway to quantify balance control during normal standing and during conditions of compromised visual and/or somatosensory feedback. Spatiotemporal gait parameters were assessed during comfortable and fast-speed walking, using an electronic walkway. Muscle strength in four lower-extremity muscle groups was measured bilaterally using a handheld dynamometer. Findings revealed that TBI patients had poorer postural balance scores across all sensory conditions, as compared to typically developing subjects. During comfortable and fast gait, TBI patients demonstrated a lower gait velocity, longer double-support phase, and increased step-length asymmetry. Further, TBI patients had a reduced strength of leg muscles and an increased strength asymmetry. Correlation analyses revealed that asymmetry in muscle strength was predictive of a poorer balance control and a more variable and asymmetric gait. To the best of our knowledge, this is the first study to measure strength asymmetry in leg muscles of a sample of TBI patients and illustrate the importance of muscular asymmetry as a potential marker and possible risk factor of impairments in control of posture and gait.

A Preliminary Exploration of Concussion and Strength Performance in Youth Ice Hockey Players

“…Furthermore, grip strength also requires far less neural recruitment being a more isolated movement that requires less coordination for a smaller body region and therefore decreased performance may resolve more quickly following concussion. Previous research on youth with a moderate to severe TBI revealed a decrease in strength and an increase in strength asymmetry compared to healthy controls [6], which supports the observation that muscle weakness may occur as a result of impairment in neurological function following a brain injury.…”

Knee extension and flexion strength asymmetry in Human Immunodeficiency Virus positive subjects: a cross-sectional study

“…According to our knowledge, this is the first study that assessed lower limb strength asymmetry in HIV-positive subjects, although these differences have also been observed in other populations, such as older adults 10 and subjects with multiple sclerosis 12 and traumatic brain injury. 11 …”

“…Previous studies with other populations demonstrated an association between muscle strength asymmetry and impaired balance or gait. Drijkoningen et al 11 demonstrated that increased asymmetry in muscle strength between D and ND limbs was associated with poorer balance control and a more variable and asymmetric gait. It is believed that, over time, an impaired balance and gait could lead to muscle imbalance, probably because the subject exerts more strength in one of the limbs.…”

“…Muscle weakness, neurological dysfunction, and frailty index have been associated with muscle strength asymmetry 10 , 11 , 12 , 13 , 14 in several populations including Parkinson's disease, 14 aging 10 , multiple sclerosis, 12 and traumatic brain injury. 11 It has been established that force asymmetry in joints or extremities can lead to improper control of body movement and postural instability, being predictive of poorer balance and a more asymmetric gait 11 , 15 and related to occurrence of injuries. 16 , 17 , 18 When detected early, muscle strength asymmetry may predict locomotor impairment and frailty 10 ; however, to the best of our knowledge, there are no studies that evaluated the occurrence of muscle strength asymmetry in HIV-positive subjects.…”

Influence of Isokinetic Knee Muscle Torque at Different Angular Velocities on Standing Posture Stability in Healthy Adults

“…It has been suggested that a decrease in the ability to generate force in the lower extremity muscles contributes to standing balance impairment [3]. A deficit in lower extremity muscle strength symmetry (knee flexor/extensor) has been identified as one of the most important intrinsic factors associated with lower extremity injuries and a risk factor for impairment in control of standing posture and gait [4]. Due to its importance, PS and/or lower extremity strength were considered to be significant components required to facilitate age-related deficits related to fall prevention or rehabilitative intervention programs in individuals [5].…”