Now showing 1 - 3 of 3
  • Publication
    Concussion recovery evaluation using the inertial sensor instrumented Y Balance Test
    The current sports concussion assessment paradigm lacks reliability, has learning effects and is not sufficiently challenging for athletes. As a result, subtle deficits in sensorimotor function may be unidentified, increasing the risk of future injury. This study examined if the inertial-sensor instrumented Y Balance test could capture concussion induced alterations in dynamic movement control. A cohort of 226 elite Rugby Union, American Football and Ice Hockey athletes were evaluated using the inertial-sensor instrumented Y balance test. Dynamic balance performance was quantified using normalised reach distance, jerk magnitude root-Mean-Squared (Jerk Mag RMS) and gyroscope magnitude sample entropy (Gyro Mag SEn). Concussed athletes who consented to follow-up were evaluated 24 to 48-hours post-injury, and at the point of return to full contact training (RTP). Seventeen athletes sustained a concussion and consented to both the 24 to 48-hour and RTP follow-up testing. Twenty uninjured control athletes were re-tested 6-months following initial screening. Concussed athletes had reductions in normalised reach distance (Cohens D=0.66-1.16) and Jerk Mag (Cohens D=0.57-1.14) 24 to 48-hours post-injury, which returned to pre-injury levels by the point of RTP. There was no significant difference in performance between the baseline and 6-month follow-up in the 20 un-injured athletes (Cohens D=0.06-0.51). There was a statistically significant linear association between Jerk Mag RMS 24 to 48-hours post-injury and the natural log of RTP duration (R2= 0.27 to 0.33). These results indicate that concussed athletes possessed alterations in dynamic movement control 24 to 48-hours post-concussion, which typically returns to pre-injury levels by the point of RTP. Furthermore, evaluation of dynamic movement control 24 to 48 hours post injury may aid in the evaluation of recovery prognosis.
    Scopus© Citations 11  598
  • Publication
    Foot Angle and Loading Rate during Running Demonstrate a Nonlinear Relationship
    Vertical loading rates are typically found to be lower in forefoot compared to rearfoot strikers, promoting the idea that forefoot striking is desirable and may reduce running injury risk. However, prior work using linear models has shown that foot inclination angle (FIA) at initial contact is a poor predictor of vertical loading rate, suggesting a more complex association exists. Purpose: To determine if a nonlinear model superiorly describes the relationship between FIA and average vertical loading rate (AVLR). Secondary analyses assessed the influence of sex and sport on the association between FIA and AVLR.Methods: Whole body kinematics and vertical ground reaction forces were collected for 170 healthy National Collegiate Athletic Association Division I athletes (97 males; 81 cross-country runners) during treadmill running at 2.68, 3.35, and 4.47 m·s−1. Foot inclination angle and AVLR were calculated for 15 strides and averaged across strides for each limb. Polynomial mixed effects models assessed linear and nonlinear trends in the relationship between FIA and AVLR across the entire sample and accounting for sex and sport participation. Results: Average vertical loading rate was lowest at the extremes of FIA (i.e., −15°, 20°), whereas greater AVLR were observed between 5° and 10°. The cubic model resulted in a significantly better fit than the linear model (P < 0.001). Average vertical loading rate was also more variable among FIA associated with rearfoot and midfoot strike than forefoot strike. Adding sex to the model did not influence model fit; though, controlling for sport minimally improved model fit. Conclusions: The relationship between FIA and AVLR is best represented by a cubic model. Consequently, FIA should be treated as a continuous variable. Reducing FIA into categories may misrepresent the relationship between FIA and other gait variables.
    Scopus© Citations 28  553
  • Publication
    Athletes with a concussion history in the last two years have impairments in dynamic balance performance
    The purpose of this study was to determine if National Collegiate Athletics Association Division 1 American Football and Ice Hockey athletes with a history of concussion have impaired dynamic balance control when compared to healthy control athletes. This cross‐sectional observational study recruited 146 athletes; 90 control athletes and 56 athletes with a history of concussion. Athletes were tested during a pre‐season evaluation using the inertial‐sensor instrumented Y Balance Test. Independent variables were normalized reach distance, gyroscope magnitude sample entropy, and jerk magnitude root mean square. Kruskal‐Wallis H test and Dunn‐Bonferroni analysis demonstrated that individuals with a concussion history within the last 2 years have statistically significantly lower jerk magnitude root mean square in the posteromedial (Z = 23.22, P = .015) and posterolateral (Z = 24.64, P = .010) reach directions, when compared to the control group. There was no significant difference between those who sustained a concussion longer than two years ago and the control group for the posteromedial (Z = −1.25; P = .889) and posterolateral (Z = 6.44; P = .469) directions. These findings show that athletes with a concussion history within the last two years possess dynamic balance deficits, when compared to healthy control athletes. Conversely, athletes whose injury occurred greater than 2 years ago possessed comparable performance to the healthy controls. This suggests that sensorimotor control deficits may persist beyond clinical recovery, for up to 2 years. Therefore, clinicians should integrate balance training interventions into the return‐to‐play process to accelerate sensorimotor recovery and mitigate the risk of future injury.
    Scopus© Citations 9  431