RESUMO
Our purpose was to identify the rate of abnormal single-task and dual-task gait performance acutely post-concussion relative to uninjured controls using previously established normative reference values. We examined athletes with a concussion (n=54; mean age=20.3±1.1 years of age, 46% female, tested 2.9±1.5 days post-injury) and healthy controls tested during their preseason baseline examination (n=60; 18.9±0.7 years of age, 37% female). Participants completed an instrumented single/dual-task gait evaluation. Outcome variables included average walking speed, cadence, and step length. A significantly greater number of those with concussion walked with abnormal dual-task gait speed compared to the control group (56% vs. 30%; p= 0.008). After adjusting for potential confounding variables (age, concussion history, symptom severity, and sleep), concussion was associated with lower dual-task gait speed (ß=-0.150; 95% CI=-0.252,-0.047), cadence (ß= -8.179; 95% CI=-14.49,-1.871), and stride length (ß=-0.109; 95% CI=-0.204,-0.014). Although group analyses indicated that those with a concussion performed worse on single-task and dual-task gait compared to controls, a higher rate of abnormal gait was detected for the concussion group compared to the control group for dual-task gait speed only. Dual-task gait speed, therefore, may be considered as a measure to compare against normative values to detect post-concussion impairments.
Assuntos
Concussão Encefálica/fisiopatologia , Transtornos Neurológicos da Marcha/fisiopatologia , Atletas , Estudos Transversais , Feminino , Humanos , Masculino , Equilíbrio Postural , Estudos Prospectivos , Valores de Referência , Análise e Desempenho de Tarefas , Adulto JovemRESUMO
CONTEXT: Fatigue in overhead athletes reduces shoulder muscular contraction and proprioception. These deficits may lead to alterations in scapular upward rotation, which is associated with multiple chronic shoulder conditions prevalent in tennis players. OBJECTIVE: To identify the effect of a functional fatigue protocol on scapular upward rotation in collegiate male tennis players. DESIGN: Randomized controlled clinical trial. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: Twenty healthy male tennis players with no history of shoulder injury completed this study. Participants were divided into 2 groups, experimental (age = 19.4 ± 1.1 years, height = 180.1 ± 8.9 cm, weight = 72.7 ± 11.6 kg) and control (age = 19.6 ± 1.2 years, height = 181.1 ± 6.6 cm, weight = 81.6 ± 13.5 kg). INTERVENTION(S): Participants in the experimental group performed a tennis-serving protocol until the onset of fatigue. Fatigue was defined as a participant reporting a rating of 15 on the Borg Scale of Perceived Exertion and reaching a heart rate of 70% of maximum. Instead of completing the fatigue protocol, control participants rested for an interval time matched to the experimental group. MAIN OUTCOME MEASURE(S): Scapular upward rotation of the dominant arm was measured at rest and at 60°, 90°, and 120° of glenohumeral elevation in the scapular plane. Upward-rotation measurements were taken prefatigue, postfatigue, and at 24, 48, and 72 hours postexercise. Scapular upward-rotation values were calculated as change scores from baseline and analyzed using a 2 × 4 mixed-model analysis of variance. RESULTS: Significant group-by-time interaction effects were found in postfatigue change scores. The experimental group displayed scapular upward-rotation deficits at all testing positions postfatigue (rest: -2.1° ± 1.4°, 60°: -2.2° ± 2.2°, 90°: -3.2° ± 2.1°, 120°: -4.0° ± 1.3°). No differences were observed at 24, 48, or 72 hours after the fatigue protocol. CONCLUSIONS: Fatigue impaired scapular upward rotation in male tennis players, but values returned to baseline within 24 hours. Clinicians should monitor scapular upward rotation in tennis players returning to competition within a day after heavy serving activity.