@article{ref1,
title="Balance regularity among former high school football players with or without a history of concussion",
journal="Journal of athletic training",
year="2018",
author="Schmidt, Julianne D. and Terry, Douglas P. and Ko, Jihyun and Newell, Karl M. and Miller, L. Stephen",
volume="53",
number="2",
pages="109-114",
abstract="CONTEXT:   Subclinical postural-control changes may persist beyond the point when athletes are considered clinically recovered postconcussion. <br><br>OBJECTIVE:   To compare postural-control performance between former high school football players with or without a history of concussion using linear and nonlinear metrics. <br><br>DESIGN:   Case-control study. SETTING:   Clinical research laboratory. PATIENTS OR OTHER PARTICIPANTS:   A total of 11 former high school football players (age range, 45-60 years) with 2 or more concussions and 11 age- and height-matched former high school football players without a history of concussion. No participant had college or professional football experience. MAIN OUTCOME MEASURE(S):   Participants completed the Sensory Organization Test. We compared postural control (linear: equilibrium scores; nonlinear: sample and multiscale entropy) between groups using a 2 × 3 analysis of variance across conditions 4 to 6 (4: eyes open, sway-referenced platform; 5: eyes closed, sway-referenced platform; 6: eyes open, sway-referenced surround and platform). <br><br>RESULTS:   We observed a group-by-condition interaction effect for medial-lateral sample entropy ( F2,40 = 3.26, P =.049, ηp2 = 0.140). Participants with a history of concussion presented with lower medial-lateral sample entropy values (0.90 ± 0.41) for condition 5 than participants without a history of concussion (1.30 ± 0.35; mean difference = -0.40; 95% confidence interval [CI] = -0.74, -0.06; t20 = -2.48, P =.02), but conditions 4 (mean difference = -0.11; 95% CI: -0.37, 0.15; t20 = -0.86, P =.40) and 6 (mean difference = -0.25; 95% CI: -0.55, 0.06; t20 = -1.66, P =.11) did not differ between groups. <br><br>CONCLUSIONS:   Postconcussion deficits, detected using nonlinear metrics, may persist long after injury resolution. Subclinical concussion deficits may persist for years beyond clinical concussion recovery.<p /> <p>Language: en</p>",
language="en",
issn="1062-6050",
doi="10.4085/1062-6050-326-16",
url="http://dx.doi.org/10.4085/1062-6050-326-16"
}