Brain Injury Research
The Brain Injury program led by Dr Andrew Gardner studies sport-related concussions. The program spans research across the full spectrum of concussion, from the acute diagnosis, assessment, and management as well as examining the longer-term issues of repeated concussion in older or retired athletes.
Our research program has collaborated with a former dual international rugby league and rugby union representative, biomechanics colleagues, and Harvard Medical School to evaluate brain movement during various tackling techniques to identify which techniques may be less of a risk for sustaining a concussion for the tackler. We have been working to:
(i) Identify the risk for tacklers in professional rugby league match play. We conducted a case–control study of tackle-based risk factors in the National Rugby League, to: (i) identify at-risk game play characteristics to reduce head contact for the ball carrier and the tackler; and (ii) tackling techniques that reduce head contact for the ball carrier and the tackler.
(ii) Determine Coaching Efficacy. We have evaluated the knowledge and skill transfer of within-session coaching and execution of the various tackle techniques of participants through biomechanical analysis.
(iii) Validate the various tackling techniques’ safety. We quantified the tackler’s brain movement when executing various tackling techniques, and determine whether one technique reduces the risk for concussive injury.
i. Match Play Video Review and Analysis
This research program has reviewed match play video of head impact events, head injury assessments, and medically diagnosed concussions in professional rugby league and rugby union. This ongoing research program aims to review and refine the video signs of concussion as an adjunct tool for the medical professional to assist in the management of game day incidents.
i. Gardner AJ, Kohler R, McDonald W, Tucker R, Fuller GW, & Makdissi M. (2018). The use of sideline video review to facilitate management decisions following head trauma in Super Rugby. Sports Medicine – Open, in press.
ii. Gardner AJ, Howell DR, Iverson GL. (2018). A video review of multiple concussion signs in National Rugby League match play. Sports Med Open, 4, 5.
iii. Gardner AJ, Howell DR, Levi CR, & Iverson GL. (2017). Evidence of Concussion Signs in National Rugby League Match Play: A Video Review and Validation Study. Sports Medicine – Open, 3(1):26.
iv. Gardner AJ, Levi CR, & Iverson GL. (2017). Observational Review and Analysis of Concussion: A Method for Conducting a Standardised Video Analysis of Concussion in Rugby League. Sports Medicine – Open, 3:26.
v. Gardner AJ, Kohler RMN, Levi CR, & Iverson GL. (2017). Usefulness of Video Review of Possible Concussions in National Youth Rugby League. International Journal of Sports Medicine, 38(1):71-75.
vi. Gardner AJ, Iverson GL, Stanwell P, Moore T, Ellis J, & Levi CR. (2016). A Video Analysis of Use of the New 'Concussion Interchange Rule' in the National Rugby League. International Journal of Sports Medicine, 37(4):267-273.
vii. Gardner AJ, Iverson GL, Quinn T, Makdissi M, Levi CL, Shultz SR, Wright D, & Stanwell P. (2015). A preliminary video analysis of concussion in the National Rugby League. Brain Injury, 29(10): 1182–1185.
ii. Impact Sensor Validation
This research program is examining the use of impact sensors to quantify the extent and quantity of impacts that occur during match play, and validate the tool as a possible adjunct tool for the identification of possible concussion in match play. This research program will conduct:
- Video verification research examining direct head impacts
- Peak accelerations associated with medically diagnosed concussions
- Associations between peak acceleration thresholds and cumulative exposure and visible signs of concussion on video
- Comparison of acceleration thresholds associated with direct head impacts and indirect head impacts
i. Carey L, Stanwell P, Terry DP, McIntosh AS, Caswell SV, Iverson GL, & Gardner AJ. (2019). Verifying head impacts recorded by a wearable sensor using video footage in rugby league: A preliminary study. Sports Medicine – Open, 5(1):9.
iii. Sports Concussion Assessment Tool (SCAT) Research
The SCAT is a tool that has been universally adopted as a clinical support tool for day of game and subsequent assessment, of an athlete suspected of having sustained a concussion. Our research program has evaluated the performance of fatigued athletes on the SCAT, and evaluated video signs, day of game SCAT performance and subsequent medical diagnosis of concussion. We are continuing to be involved in collaborative work on the SCAT and conduct our own research looking at day of game performance, baseline performance, and serial use of the SCAT.
i. Chung Pin Yong JP, Howell DR, Meehan WP, Iverson GL, & Gardner AJ.(2018). Effects of Exercise on Sports Concussion Assessment Tool-Third Edition Performance in Amateur Female Athletes. Clinical Journal of Sports Medicine, in press.
ii. Gardner AJ, Wojtowicz M, Terry D, Levi CR, Zafonte R, & Iverson GL. (2017). Video and Clinical Screening of Australian National Rugby League Players Suspected of Sustaining Concussion, Brain Injury, in press.
iii. Lee JH, Howell DR, Meehan WP, Iverson GL, & Gardner AJ.(2017). Effects of Exercise on Sports Concussion Assessment Tool-Third Edition Performance in Professional Athletes. The Orthopaedic Journal of Sports Medicine, 5(9):2325967117727261.
iv. Cognitive Assessment Validation Research
The clinical validation program is focused on creating a normative database, while also examining construct validity (convergent and divergent validity), and test retest reliability (sensitivity, specificity, positive predictive value, and negative predictive value) of a number of unique tools in an attempt to advance the sensitivity of detecting subtle cognitive deficits in concussed athletes, and to track their cognitive recovery over time.
The Brain Injury research program also conducts a number of studies in conjunction with the clinic service operated by the Local Health District’s sports concussion clinic. Clinic Co-Director’s Professor Levi and Dr Gardner are accumulating a large clinical research database to answer a number of sports concussion-related research questions regarding clinical care of community level athletes. The rich clinical database enables the research program to interrogate the data of sub-acute concussion and clinical recovery among a number of other clinically-derived research questions.
We are working on collecting sub-acute and chronic neuroimaging on current and former collision and contact sports athletes who are suffering from or have had a history of concussion.
i. Conley AC, Cooper P, Karayanidis F, Gardner AJ, Levi CR, Stanwell P, Gaetz M, & Iverson GL. (2019). Resting state electroencephalography and sport-related concussion: A systematic review. Journal of Neurotrauma, online first.
ii. Gardner AJ, Tan CO, Ainslie PN, van Donkelaar P, Stanwell P, Levi CR, & Iverson GL. (2015). Cerebrovascular reactivity assessed by transcranial Doppler ultrasound in sport-related concussion: a systematic review. British Journal of Sports Medicine, 49(16):517-526.
iii.Gardner AJ, Iverson GL, Stanwell P. (2014). A systematic review of proton magnetic resonance spectroscopy findings in sport-related concussion. Journal of Neurotrauma. 31(1): 1-18.
iv. Gardner A, Kay-Lambkin F, Stanwell P, Donnelly J, Williams WH, Hiles A, Schofield P, Levi C, Jones DK. (2012). A systematic review of diffusion tensor imaging findings in sports-related concussion. Journal of Neurotrauma. 29(16): 2521-2538.
The Retired Professional Rugby Players Brain Health Study commenced in 2012 and has become a large, multidisciplinary, multinational, and multi-year program of research that is working towards advancing our understanding of later-in-life brain health in former professional rugby league and rugby union players. The objectives of this program include:
Aim 1: The Retired Rugby Players Health Survey. A health survey study is available to all former rugby players. Developed over two years in collaboration with colleagues at Harvard Medical School the survey will help our understanding of the health, well-being, and quality of life of former professional rugby players. From this data, we will attempt to determine the extent to which former players might benefit from specific types of health care services.
Aim 2: Examine the Brain Health of Retired Professional Rugby Players (In-person Clinical Evaluation and Multimodal Neuroimaging). We are conducting an in-person comprehensive study of the brain health of retired professional rugby players. This study involves extensive psychological testing, cognitive testing, and multimodal experimental brain imaging, with the purpose of comprehensively evaluating the brain health of former professional rugby players.
As at the end of August 2019 there are 108 retired rugby players who have completed the in-person clinical evaluation and a sub-set who have completed both the in-person clinical evaluation and multimodal neuroimaging. Many of the recruited participants are now returning for a second (i.e., repeat/serial) assessment.
i. Gardner AJ, Iverson GL, Wojtowicz M., Levi C.R., Kay-Lambkin F., Schofield P.W., Shultz S.R., Zafonte R.D., Lin A.P., & Stanwell P. (2017). MR Spectroscopy Findings in Retired Professional Rugby League Players. International Journal of Sports Medicine, 38(3):241-252.
ii. Wojtowicz M, Gardner AJ, Stanwell P, Zafonte RD, Dickerson B, & Iverson GL. (2018). Cortical and subcortical brain volumes in retired professional rugby league players. NeuroImage: Clinical, 18:377-381.
iii. Iverson GL, Terry DP, Luz M, Zafonte R, McCrory P, Solomon GS, & Gardner AJ. (2019). Anger and depression in middle-aged men: Implications for a clinical diagnosis of Chronic Traumatic Encephalopathy. Journal of Neuropsychiatry and Clinical Neurosciences, in press.
iv. Iverson GL, Gardner AJ, Shultz SR, Solomon G, McCrory PE, Zafonte RD, Perry G, Hazrati L, Keene CD, & Castellani R. (2019). Chronic Traumatic Encephalopathy Neuropathology Might Not Be Inexorably Progressive or Unique to Repetitive Neurotrauma. Brain, in press.
v. Iverson GL, & Gardner AJ. (2019). Risk for Misdiagnosing Chronic Traumatic Encephalopathy in Men with Depression. Journal of Neuropsychiatry and Clinical Neurosciences, in press.
vi. Manley GT, Gardner AJ, Schneider KJ, Guskiewicz KM, Bailes J, Cantu RC, Castellani RJ, Turner M, Jordan B, Randolph C, Dvořák J, Tator CH, McCrory P, & Iverson GL. (2017). A Systematic Review of Potential Long-Term Effects of Sport-Related Concussion. British Journal of Sports Medicine, 51(12):969-977.
vii. Iverson GL, Gardner AJ, McCrory P, Zafonte R, & Castellani R. (2015). A critical review of Chronic Traumatic Encephalopathy. Neuroscience & Biobehavioral Reviews, 56: 276-293.
viii. Gardner AJ, Iverson GL, McCrory P. (2014). Chronic traumatic encephalopathy in sport: as systematic review. British Journal of Sports Medicine. 48(2): 84-90.
ix. McCrory P, Meeuwisse WH, Kutcher JS, Jordan BD, Gardner AJ. (2013). What is the evidence for chronic concussion-related changes in retired athletes: behavioural, pathological and clinical outcomes? British Journal of Sports Medicine. 47(5): 327-330.