Sports Medicine Research: In the Lab & In the Field (Sports Med Res)
Wednesday, July 29, 2015

Should You be Nervous about Neural Changes Following ACL Surgery?

Neural excitability alterations after anterior cruciate ligament reconstruction.

Pietrosimone BG, Lepley AS, Ericksen HM, Clements A, Sohn DH, and Gribble PA. J Athl Training. 2015; 50(6) 665-674.

Take Home Message: Following anterior cruciate ligament (ACL) surgery, patients have changes in the excitability of pathways that go from the brain (primary motor cortex) and down the spinal cord when compared with an uninjured limb as well as healthy control participants.

Many patients experience neuromuscular deficits after ACL reconstruction (ACLR). These deficits may be caused by changes in spinal-reflex excitability or corticomotor excitability, which is the excitability of the brain (primary motor cortex) and the related descending pathways in the spinal cord. By understanding the neural changes that occur in patients after an ACLR, clinicians may be able to improve ACLR rehabilitation to improve knee function, reduce the risk of reinjury, and potentially protect long-term joint health. Therefore, Pietrosimone and colleagues completed a case-control study to determine whether corticomotor and spinal-reflex excitability differed between individuals with an ACLR and healthy controls.
Monday, July 27, 2015

Accuracy, Affordability, and Portability! Use Your Tablet To Detect Postural Instability

Using accelerometer and gyroscopic measures to quantify postural stability

Alberts JL, Hirsch JR, Koop MM, Schindler DD, Kana DE, Linder SM, Campbell S, Thota AK. Journal of Athletic Training 2015;50(6):578–588.

Take Home Message: Tablet hardware provided accurate data to quantify postural stability within 2.9° of data generated from a force platform system.

Postural instability deficits are frequently reported following a concussion. The balance errors scoring system (BESS) is a commonly used postural stability assessment; however, there are some limitations to its clinical utility (for example, its consistency between clinicians is low). Force platforms and 3-dimensional motion capture systems (for example, NeuroCom) are a more accurate method to assess postural instability; but due to the high cost it is not readily available for most medical professionals. Therefore, the authors determined whether postural instability could be quantified accurately with data gathered by an accelerometer and gyroscope within a tablet.
Tuesday, July 21, 2015

Increased Risk of Acute Lower Extremity Injury For Up To a Year Following Concussion

Acute Lower Extremity Injury Rates Increase following Concussion in College Athletes

Lynall RC, Mauntel TC, Padua DA, Mihalik JP. Med Sci Sport Exerc. 2015; ahead of print

Take Home Message: College athletes are nearly 2 times more likely to sustain an acute lower extremity injury for up to 1-year post concussion compared with a year before the concussion.

Neuromuscular control deficits change functional movement patterns during simple gait activities (for example, increase sway area) following a concussion. These changes continue well beyond the athlete’s full return-to-play, which is worrisome because these lingering changes may put the athlete at risk for a lower extremity injury. However, there is limited research addressing the risk of lower extremity injury following a concussion. Therefore, the authors investigated the risk of lower extremity musculoskeletal injury pre and post concussion in a cohort of 44 Division I athletes within 3 time periods around a concussion injury (± 90, ± 180, and ± 360 days). The authors also compared concussed athletes with 58 healthy matched controls.
Wednesday, July 15, 2015

Does Sport Participation Give You a Longer Life?

All-cause and disease-specific mortality among male, former elite athletes: an average 50-year follow-up.

Kettunen JA, Kujala UM, Kaprio J, Backmand H, Peltonen M, Eriksson JG, and Sarna S. Br J Sports Med. 2015. 49:893-897.

Take Home Message: Former elite athletes have a longer life expectancy than demographically-matched control patients. Those athletes participating in soccer, basketball, ice hockey, jumping, short distance running, hurdling, cross-country skiing, middle and long distance runners suffer from heart disease less than control patients.

Observational studies can enhance a clinician’s understanding about the long-term outlook for a population including, quality of life, and mortality. For example, if clinicians better understand if participation in certain sports or level of competition compromised long-term health, then some type of early intervention program may be devised to limit the risk of chronic disease. Therefore, Kettunen and colleagues completed retrospective cohort study to investigate the life expectancy and mortality rates of former elite athletes.
Monday, July 13, 2015

Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015

Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015.

Hew-Butler T, Rosner MH, Fowkes-Godek S, Dugas JP, Hoffman MD, Lewis DP, Maughan RJ, Miller KC, Montain SJ, Rehrer NJ, Roberts WO, Rogers IR, Siegel AJ, Stuempfle KJ, Winger JM, Verbalis JG. Clin J Sport Med. 2015 Jul;25(4):303-20. doi: 10.1097/JSM.0000000000000221.
Full Text Freely Available (has an accompanying podcast)

The third International Exercise-Associated Hyponatremia (EAH) Consensus Development Conference (2015) has updated a 2008 consensus statement and hopes this new version will help “launch an educational campaign designed to address the morbidity and mortality associated with a preventable and treatable fluid imbalance.” After a brief discussion about the consensus methodology the authors define EAH and review the epidemiology, risk factors, etiology and pathophysiology of EAH. The authors also discuss the role of thirst, clinical classification and diagnosis of EAH, treatment, and prevention. The document concludes with a summary of 9 recommendations.  

Wednesday, July 8, 2015

Balancing Chronic Ankle Instability

Effects of 6 Weeks of Balance Training on Chronic Ankle Instability in Athletes: A Randomized Controlled Trial.

Cruz-Diaz D, Lomas-Vega R, Osuna-Perez MC, Contreras FH, and Martinez-Amat A. Int J Sports Med. 2015; E pub ahead of print. DOI: 10.1055/s-0034-1398645.

Take Home Message: A 6-week lower-extremity training program that incorporates progressive balance exercises is effective in reducing feelings of instability and improving dynamic balance in athletes with chronic ankle instability.

Ankle sprains are very common within the athletic and physically active populations and can lead to chronic issues such as chronic ankle instability (CAI).  CAI results in residual symptoms and “giving way”, which can leave someone susceptible to further injury, decreased quality of life, and potential degenerative joint changes.  Balance training may help mitigate some of these short- and long-term issues.  The authors of this randomized clinical trial investigated whether a 6-week balance training program helped improve feelings of instability, pain, and dynamic balance in athletes with CAI.
Monday, July 6, 2015

Structural Brain Changes Associated to Concussion History and Cognition

Imaging correlates of memory and concussion history in retired national football league athletes

Strain JF., Womack KB., Didehbani N., Spence JS., Conover H., Hart J. Kraut MA., Cullum CM. JAMA Neurology. 2015; ahead of print

Take Home Message: Prior concussion that resulted in loss of consciousness is a risk factor for decreased hippocampal regions and mild cognitive impairment later in life.

Long-term memory dysfunction (for example, Alzheimer’s disease, mild cognitive impairment) after a concussion injury remains poorly understood and it is still debated whether concussions cause these impairments. Changes in the brain (for example, hippocampal atrophy) may be related with a history of concussions and mild cognitive impairment and learning more about these relationships may help us understand the relationship between concussions and memory impairments. Therefore, the authors measured hippocampal volumes with Functional Magnetic Resonance Imaging, performed neuropsychological tests, and collected descriptive information to determine the relationship of memory performance with hippocampal volume coupled with the influence of concussion history in 28 retired National Football League (NFL) athletes (36-79 years of age, education ranged from 15-18 years, estimated IQ ranged 92-126, 2-15 years of NFL experience, and 8 had mild cognitive impairment with concussion history).