Now showing 1 - 10 of 21
  • 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.
      434Scopus© Citations 9
  • Publication
    Validation of temporal gait metrics from three IMU locations to the gold standard force plate
    The purpose of this work is to compare temporal gait parameters from three different IMU locations to the gold standard force platform. 33 subjects (12 F, 21 M) performed twenty gait trials each while wearing inertial measurement units (IMUs) on the trunk, both shanks and both feet. Data was simultaneously collected from a laboratory embedded force plate. Step times were derived from the raw IMU data at the three IMU locations using methods that have been shown to be accurate. Step times from all locations were valid compared to the force plate. Foot IMU step time was the most accurate (Pearson = .991, CI width = 3.00e2), the trunk IMU was the next most accurate (Pearson = .974, CI width = 4.85e2) and shank step time was the least accurate (Pearson = .958, CI width = 6.80e2). All three sensing locations result in valid estimations of step time compared to the gold standard force plate. These results suggest that the foot location would be most appropriate for clinical applications where very precise temporal parameter detection is required.
      784Scopus© Citations 12
  • Publication
    Quantifying Y Balance Test performance with multiple and single inertial sensors
    A growing body of evidence has highlighted that inertial sensor data can increase the sensitivity and clinical utility of the Y Balance Test, a commonly used clinical dynamic balance assessment. While early work has demonstrated the value of a single lumbar worn inertial sensor in quantifying dynamic balance control, no research has investigated if alternative (shank) or combined (lumbar and shank) sensor mounting locations may improve the assessments discriminant capabilities. Determining the optimal sensor set-up is crucial to ensuring minimal cost and maximal utility for clinical users The aim of this cross-sectional study was to investigate if single or multiple inertial sensors, mounted on the lumbar spine and/or shank could differentiate young (18-40 years [n = 41]) and middle-aged (40-65 years [n = 42]) adults, based on dynamic balance performance. Random-forest classification highlighted that a single lumbar sensor could classify age-related differences in performance with an accuracy of 79% (sensitivity = 81%; specificity = 78%). The amalgamation of shank and lumbar data did not significantly improve the classification performance (accuracy = 73-77%; sensitivity = 71-76%; specificity = 73-78%). Jerk magnitude root-mean-square consistently demonstrated predictor importance across the three reach directions: posteromedial (rank 1), anterior (rank 3) and posterolateral (rank 6).
      20
  • Publication
    Association of dynamic balance with sports related concussion: a prospective cohort study
    Background: Concussion is one of the most common sports-related injuries, with little understood about the modifiable and non-modifiable risk factors. Researchers have yet to evaluate the association between modifiable sensorimotor function variables and concussive injury. Purpose: To investigate the association between dynamic balance performance, a discrete measure of sensorimotor function, and concussive injuries. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A total of 109 elite male rugby union players were baseline tested in dynamic balance performance while wearing an inertial sensor and prospectively followed during the 2016-2017 rugby union season. The sample entropy of the inertial sensor gyroscope magnitude signal was derived to provide a discrete measure of dynamic balance performance. Logistic regression modeling was then used to investigate the association among the novel digital biomarker of balance performance, known risk factors of concussion (concussion history, age, and playing position), and subsequent concussive injury. Results: Participant demographic data (mean 6 SD) were as follows: age, 22.6 6 3.6 years; height, 185 6 6.5 cm; weight, 98.9 612.5 kg; body mass index, 28.9 6 2.9 kg/m2; and leg length, 98.8 6 5.5 cm. Of the 109 players, 44 (40.3%) had a history of concussion, while 21 (19.3%) sustained a concussion during the follow-up period. The receiver operating characteristic analysis for the anterior sample entropy demonstrated a statistically significant area under the curve (0.64; 95% CI, 0.52-0.76; P \ .05), with the cutoff score of anterior sample entropy 1.2, which maximized the sensitivity (76.2%) and specificity (53.4%) for identifying individuals who subsequently sustained a concussion. Players with suboptimal balance performance at baseline were at a 2.81-greater odds (95% CI, 1.02-7.74) of sustaining a concussion during the rugby union season than were those with optimal balance performance, even when controlling for concussion history. Conclusion: Rugby union players who possess poorer dynamic balance performance, as measured by a wearable inertial sensor during the Y balance test, have a 3-times-higher relative risk of sustaining a sports-related concussion, even when controlling for history of concussion. These findings have important implications for research and clinical practice, as it identifies a potential modifiable risk factor. Further research is required to investigate this association in a large cohort consisting of males and females across a range of sports.
      635Scopus© Citations 25
  • 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.
      601Scopus© Citations 11
  • Publication
    Wearable sensing and mobile devices: the future of post-concussion monitoring?
    In the past decade, concussion has received large amounts of attention in public, medical and research circles. While our understanding of the nature and management of concussion has greatly improved, there are still major limitations which need to be addressed surrounding the identification of the injury, determining when an individual is safe to return to normal activity, and what factors may contribute to the development of post-concussion syndrome (PCS).The current model of concussion management involves a triage evaluation in the acute stage of injury, focusing on the classic signs and symptoms of concussion. Next, the clinician attempts to evaluate key components of cerebral function through clinical symptom evaluation, and traditional assessments of motor and neurocognitive function [1]. The development of the sports concussion assessment tool (SCAT) saw a massive leap forward in the strategies employed in the management of concussion, as it acknowledged the multifactorial nature of concussion, and provided a standardised means for clinicians to assess the many domains of cerebral function [2]. While these methods have demonstrated some promise in the acute stage, they are not designed for serial monitoring (particularly in instances where PCS develops) [3], and provide us with very little clinically relevant information that can assist clinicians in the return to learn/ sport/ performance process.
      415
  • Publication
    Inter-session test-retest reliability of the quantified Y balance test
    The Y Balance test is the most common dynamic balance assessment used in clinical practice and research. However, the traditional measure of performance, the reach distance, fails to provide detailed information pertaining to the control of balance during the reach task. Recent research has demonstrated that a single wearable inertial sensor can capture detailed information pertaining to balance performance during the Y balance test, not captured by the traditional reach distances. To date, no research has been conducted investigating the inter-session test-retest reliability of the inertial sensor instrumented YBT. Thirty -two young healthy adults, aged between 18-40 were recruited as part of this study. Participants completed the quantified YBT protocol during two testing sessions, separated by 7-10 days. The findings from this study demonstrated that 26/36 (anterior), 31/36 (posteromedial) and 33/36 (posterolateral) quantified variables demonstrated good-excellent intra-session test-retest reliability. These findings suggest that the inertial sensor quantified YBT can provide a reliable measure of dynamic balance performance. Further research is required to investigate the capability of the quantified YBT to identify individuals at risk of injury/ disease and track recovery/ response to intervention.
      633Scopus© Citations 7
  • Publication
    Challenging Concussed Athletes: The Future of Balance Assessment in Concussion
    The assessment and management of sports-related concussion has become a contentious issue in the field of sports medicine. The current consensus in concussion evaluation involves the use of a subjective examination, supported by multifactorial assessment batteries designed to target the various components of cerebral function. Balance assessment forms an important component of this multifactorial assessment, as it can provide an insight into the function of the sensorimotor subsystems post-concussion. In recent times, there has been a call to develop objective clinical assessments that can aid in the assessment and monitoring of concussion. However, traditional static balance assessments are derived from neurologically impaired populations, are subjective in nature, do not adequately challenge high functioning athletes and may not be capable of detecting subtle balance disturbances following a concussive event. In this review, we provide an overview of the importance of assessing motor function following a concussion, and the challenges facing clinicians in its assessment and monitoring. Additionally, we discuss the limitations of the current clinical methods employed in balance assessment, the role of technology in improving the objectivity of traditional assessments, and the potential role inexpensive portable technology may play in providing objective measures of more challenging dynamic tasks.
      281Scopus© Citations 22
  • Publication
    Objective quantification of a clinical dynamic balance assessment
    Objective: To investigate whether addition of inertial sensor data can provide additional insight into the nature of postural stability deficits during a clinical dynamic balance assessment, with a view to enhancing accuracy of post-concussion monitoring protocols. Design: Descriptive laboratory study. Setting: University performance laboratory. Participants: Fifteen physically active adults (age 234 years, height 1758 cm, weight 67.58 kg). Interventions: An inertial measurement unit (IMU) was mounted at the level of the 4th lumbar vertebra. Subjects completed repeated Y-Balance tests (YBT) 10 minutes and immediately prior to a modified 60 second Wingate anaerobic fatiguing test. Post-fatigue YBTs were completed immediately following the test, and at 10 and 20 minutes.Outcome measures: Normalised YBT reach distances, and IMU derived RMS acceleration, velocity and angular velocity. Main results: Prior to the fatiguing intervention, participants demonstrated excellent stability/reliability for all reach directions (Intra-class correlation coefficient 0.872-0.994). Significantly lower reach distances (P<0.05) were observed immediately post-fatigue for the postero-medial and postero-lateral, but not anterior reach direction. Observed deficits returned to pre-fatigue levels by 10 minutes. However, IMU derived measures of postural stability remained significantly reduced (P<0.05) for up to 20 minute post-fatigue. Conclusions: These results demonstrate the ability of both traditional YBT reach distances and inertial sensor data to detect centrally driven postural stability deficits. However, the inertial sensor provided a greater degree of granularity in characterising the nature of these postural stability deficits. This suggests that addition of IMUs to clinical balance measurement tests/protocols may better detect deficits associated with concussion.
      356
  • Publication
    Investigating normal day to day variations in postural control in a healthy young population (age 18-40) using wii balance boards
    Objective me asurements of postural control are frequently used to examine the causes of, features associated with, and therapeutic interventions for ankle instability. However, researchers have typically used single-session measures to represent postural control at one point in time. Recent studies in a healthy elderly population demonstrate significant variations in day-to-day postural control and suggest that single-session measurement may not truly reflect postural control capabilities. An investigation into patterns of day-to-day variation in postural control in a younger population are warranted.
      319