The persistent effect of concussion history on gait outcomes and lower extremity biomechanics associated with anterior cruciate ligament injury risk
Date
2024
Authors
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Publisher
University of Delaware
Abstract
Concussion has emerged as a major health concern in sports medicine, with an incidence rate of 4.47 per 10,000 athletic exposures among college students in the US. Recent evidence indicates that individuals with a history of concussion exhibit altered gait and jump-landing biomechanics, which are associated with an increased risk of lower extremity musculoskeletal injury (LEMI). Studies suggest that incorporating cognitive tasks into motor tasks can create a more sport-like performance scenario, potentially enhancing the sensitivity for detecting movement alterations post-concussion. These findings suggest that concussions have long-term effects beyond clinical recovery and underscore the need to incorporate cognitive tasks into motor assessments to better understand movement alterations in individuals with a prior concussion. Additionally, conventional biomechanical approaches may not be practical for healthcare providers to integrate into clinical practice. The Landing Error Scoring System (LESS) offers a simple, field-based screening tool designed to evaluate biomechanical movement patterns linked to non-contact ACL injuries. Therefore, this dissertation aims to: (1) determine the effect of motor and cognitive demands during walking and jump-landing tasks between individuals with and without a concussion history, and (2) compare the scores of a clinical measure for jump-landing mechanics between these groups. This dissertation project has three aims. ☐ Aim 1: To compare gait speed during single- and dual-task conditions between individuals with and without a concussion history within the past year. Hypothesis 1.1: Individuals with a concussion history will have slower gait speed during single and dual-task conditions than those without. Hypothesis 1.2: Individuals with a concussion history will have a greater dual-task cost on gait speed than those without. Results: Both groups demonstrated comparable gait performance during single- and dual-task conditions, with gait speed in the concussion history group similar to normative values. ☐ Aim 2: To compare unilateral lower extremity biomechanics and their symmetry during jump-landing tasks with different levels of motor and cognitive demand between individuals with and without a concussion history in the past year. Hypothesis 2.1: Individuals with a concussion history will exhibit unfavorable sagittal plane landing biomechanics and greater asymmetry in sagittal plane landing biomechanics compared to those without in all jump-landing tasks. Hypothesis 2.2: The effect of task difficulty on sagittal plane landing mechanics and asymmetry will be greater among individuals with a concussion history than those without. Results: Individuals with a recent concussion demonstrated similar lower extremity biomechanics in most of measured outcomes during jump-landing compared to the healthy reference group; however, they displayed lower posterior ground reaction force on their non-dominant legs. ☐ Aim 3: To compare LESS scores and symmetry between individuals with and without a concussion history. Hypothesis 3.1: Individuals with a concussion history will have greater and more asymmetrical LESS scores than those without. Hypothesis 3.2: Individuals with a concussion history are more likely to exhibit hazardous landing strategies (LESS≥5) than those without. Results: The LESS effectively identified high-risk movement patterns in individuals with a recent concussion. Additionally, these individuals displayed multiple unfavorable jump-landing mechanics, leading to overall high-risk movement patterns associated with LEMI. ☐ Conclusions: Our findings indicate that individuals with a recent concussion (< 1 yr.) demonstrated gait performance similar to the established normative values. During jump-landing, those with a recent concussion history displayed comparable lower extremity biomechanics in most of measured outcomes; however, the concussion history group displayed smaller posterior ground force on their non-dominant legs compared to individuals without a concussion history. Although the underlying mechanism remains unclear, we found that the number of previous concussions was negatively associated with the posterior ground force. Future research should consider the number of prior concussions to better understand jump-landing biomechanics in individuals with a concussion history. Additionally, the LESS can effectively identify high-risk movement patterns in individuals with a recent concussion. Healthcare providers may utilize LESS to identify these high-risk patterns in individuals post-concussion and develop customized exercise interventions, rather than using it for predicting LEMI.
Description
Keywords
Concussion, Gait, Jump landing, Landing Error Scoring System, Lower extremity musculoskeletal injury