Context: Concussions are consequence of sports participation. Recent reports indicate there is an increased risk of lower-extremity musculoskeletal injury when returning to sport after concussion suggesting that achieving “normal” balance may not fully indicate the athlete is ready for competition. The increased risk of injury may indicate the need to refine a screening tool for clearance. Objective: Assess the between-session reliability and the effects of adding a cognitive task to static and dynamic postural stability testing in a healthy population. Setting: Clinical laboratory. Participants: Twelve healthy subjects (6 women; age 22.3 [2.9] y, height 174.4 [7.5] cm, weight 70.1 [12.7] kg) participated in this study. Design: Subjects underwent static and dynamic postural stability testing with and without the addition of a cognitive task (Stroop test). Test battery was repeated 10 days later. Dynamic postural stability testing consisted of a forward jump over a hurdle with a 1-legged landing. A stability index was calculated. Static postural stability was also assessed with and without the cognitive task during single-leg balance. Variability of each ground reaction force component was averaged. Main Outcome Measures: Interclass correlation coefficients (ICC2,1) were computed to determine the reliability. Standard error of measure, mean standard error, mean detectable change, and 95% confidence interval were all calculated. Results: Mean differences between sessions were low, with the majority of variables having moderate to excellent reliability (static .583–.877, dynamic .581–.939). The addition of the dual task did not have any significant effect on reliability of the task; however, generally, the ICC values improved (eyes open .583–.770, dual task .741–.808). Conclusions: The addition of a cognitive load to postural stability assessments had moderate to excellent reliability in a healthy population. These results provide initial evidence on the feasibility of dual-task postural stability testing when examining risk of lower-extremity musculoskeletal injury following return to sport in a concussed population.
Caroline Westwood, Carolyn Killelea, Mallory Faherty and Timothy Sell
Ryan Morrison, Kyle M. Petit, Chris Kuenze, Ryan N. Moran and Tracey Covassin
Context: Balance testing is a vital component in the evaluation and management of sport-related concussion. Few studies have examined the use of objective, low-cost, force-plate balance systems and changes in balance after a competitive season. Objective: To examine the extent of preseason versus postseason static balance changes using the Balance Tracking System (BTrackS) force plate in college athletes. Design: Pretest, posttest design. Setting: Athletic training facility. Participants: A total of 47 healthy, Division-I student-athletes (33 males and 14 females; age 18.4 [0.5] y, height 71.8 [10.8] cm, weight 85.6 [21.7] kg) participated in this study. Main Outcome Measures: Total center of pressure path length was measured preseason and postseason using the BTrackS force plate. A Wilcoxon signed-rank test was conducted to examine preseason and postseason changes. SEM and minimal detectable change were also calculated. Results: There was a significant difference in center of pressure path length differed between preseason (24.6 [6.8] cm) and postseason (22.7 [5.4] cm) intervals (P = .03), with an SEM of 3.8 cm and minimal detectable change of 10.5 cm. Conclusions: Significant improvements occurred for center of pressure path length after a competitive season, when assessed using the BTrackS in a sample of college athletes. Further research is warranted to determine the effectiveness of the BTrackS as a reliable, low-cost alternative to force-plate balance systems. In addition, clinicians may need to update baseline balance assessments more frequently to account for improvements.
Janelle Prince, Eric Schussler and Ryan McCann
Clinical Scenario: A sport-related concussion is a common injury to the brain that may cause a variety of symptoms ranging in duration and severity. The mainstay of treatment for concussion has been rest, followed by a stepwise return to activity. This recovery process may be lengthy when symptoms persist. Aerobic exercise conducted at subsymptom and submaximal intensities has been proposed as a potential intervention for symptoms following a concussion. Therefore, the purpose of this critically appraised topic is to examine the safety of varying aerobic exercise intensities in patients with a concussion. Focused Clinical Question: Are subsymptom and submaximal exercise programs safe when implemented in a population with a symptomatic sports-related concussion when compared with traditional rest? Summary of Key Findings: Four randomized controlled trials were included for critical appraisal. The 4 studies investigated supervised and controlled aerobic exercise as early as within 1 week of with a concussion; all studies conclude that exercise is safe and may be of benefit to individuals with a concussion. Two studies support the use of submaximal exercise as a therapeutic intervention for adolescents with persistent concussion symptoms. Clinical Bottom Line: The authors conclude that controlled exercise performed within the symptom or exertion threshold of patients with concussion is safe compared with rest. It was noted that symptom changes may occur; however, the changes did not have a negative impact on long-term recovery. This research should ease concerns about prescribing physical activity when an athlete with concussion is still experiencing lingering symptoms. While specific parameters of the activity performed have not been described in detail, the individualization of each exercise program was stressed. Strength of Recommendation: Grade A.
Yuko Kuramatsu, Yuji Yamamoto and Shin-Ichi Izumi
This study investigated the sensorimotor strategies for dynamic balance control in individuals with stroke by restricting sensory input that might influence task accomplishment. Sit-to-stand movements were performed with restricted vision by participants with hemiparesis and healthy controls. The authors evaluated the variability in the position of participants’ center of mass and velocity, and the center-of-pressure position, in each orthogonal direction at the lift-off point. When vision was restricted, the variability in the mediolateral center-of-pressure position decreased significantly in individuals with hemiparesis, but not in healthy controls. Participants with hemiparesis adopted strategies that explicitly differed from those used by healthy individuals. Variability may be decreased in the direction that most requires accuracy. Individuals with hemiparesis have been reported to have asymmetrical balance deficits, and that meant they had to prioritize mediolateral motion control to prevent falling. This study suggests that individuals with hemiparesis adopt strategies appropriate to their characteristics.
Patrick O. McKeon and Jennifer M. Medina McKeon
Marcie Fyock, Nelson Cortes, Alex Hulse and Joel Martin
Clinical Scenario: Patellofemoral pain (PFP) is a common knee injury in recreational adult runners, possibly caused by faulty mechanics. One possible approach to reduce this pain is to retrain the runner’s gait. Current research suggests that no definitive gold standard treatment for PFP exists. Gait retraining utilizing visual feedback may reduce PFP in both the short and long term. Clinical Question: In adult runners diagnosed with PFP, does gait retraining with real-time visual feedback lead to a decrease in pain? Summary of Key Findings: A literature search was performed; 3 relevant studies utilizing gait retraining with visual feedback, pain level as an outcome measure, and follow-up measures of at least 1 month after the intervention were included. All the included studies reported a decrease in short- and long-term pain for participants following visual feedback gait retraining. In addition, biomechanical measures related to PFP, including peak hip adduction angle and the angle of contralateral pelvic drop, improved after the completion of the intervention. Clinical Bottom Line: There is level 2 evidence supporting the implementation of 8 sessions over 2 weeks of visual feedback gait retraining as a means of treating patients diagnosed with PFP. Based on current available evidence, clinicians should identify faulty mechanics of patients and implement a protocol of increasing real-time visual feedback over the first 4 sessions and decreasing visual feedback over the final 4 sessions. Strength of Recommendation: Level 2.
Lauren Anne Lipker, Caitlyn Rae Persinger, Bradley Steven Michalko and Christopher J. Durall
Clinical Scenario: Quadriceps atrophy and weakness are common after anterior cruciate ligament reconstruction (ACLR). Blood flow restriction (BFR) therapy, alone or in combination with exercise, has shown some promise in promoting muscular hypertrophy. This review was conducted to ascertain the extent to which current evidence supports the use of BFR for reducing quadriceps atrophy following ACLR in comparison with standard care. Clinical Question: Is BFR more effective than standard care for reducing quadriceps atrophy after ACLR? Summary of Key Findings: The literature was searched for studies that directly compared BFR treatment to standard care in patients with ACLR. Three level I randomized control trial studies retrieved from the literature search met the inclusion criteria. Clinical Bottom Line: Reviewed data suggest that a short duration (13 d) of moderate-pressure BFR combined with low-resistance muscular training does not appear to measurably affect quadriceps cross-sectional area. However, a relatively long duration (15 wk) of moderate-pressure BFR combined with low-resistance muscular training may increase quadriceps cross-sectional area to a greater extent than low-resistance muscular training alone. The results of the third randomized control trial suggest that employing BFR while immobilized in the early postoperative period may reduce quadriceps atrophy following ACLR. Additional data are needed to establish if the benefits of BFR on quadriceps atrophy after ACLR outweigh the inherent risks and costs. Strength of Recommendation: All evidence for this review was level 1 (randomized control trial) based on the Centre for Evidence-Based Medicine criteria. However, the findings were inconsistent across the 3 studies regarding the effects of BFR on quadriceps atrophy resulting in a grade “B” strength of recommendation.
Matt Hausmann, Jacob Ober and Adam S. Lepley
Clinical Scenario: Ankle sprains are the most prevalent athletic-related musculoskeletal injury treated by athletic trainers, often affecting activities of daily living and delaying return to play. Most of these cases present with pain and swelling in the ankle, resulting in decreased range of motion and strength deficits. Due to these impairments, proper treatment is necessary to avoid additional loss of play and prevent future injuries. Recently, there has been an increased use of deep oscillation therapy by clinicians to manage pain and swelling following a variety of injuries, including ankle sprains. However, very little evidence has been produced regarding the clinical effectiveness of deep oscillation therapy, limiting its application in therapeutic rehabilitation of acute lateral ankle sprains. Clinical Question: Is deep oscillation therapy effective in reducing pain and swelling in patients with acute lateral ankle sprains compared with the current standard of care protection, rest, ice, compression, and elevation? Summary of Key Findings: The literature was searched for studies of level 2 evidence or higher that investigated deep oscillation therapy on pain and inflammation in patients with lateral ankle sprains. Three randomized control trials were located and appraised. One of the 3 studies demonstrate a reduction in pain following 6 weeks of deep oscillation therapy compared with the standard of care or placebo interventions. The 2 other studies, 1 utilizing a 5-day treatment and the other a 1 time immediate application, found no differences in deep oscillation therapy compared with the standard of care. Clinical Bottom Line: There is inconclusive evidence to support the therapeutic use of deep oscillation therapy in reducing pain and swelling in patients with acute lateral ankle sprains above and beyond the current standard of care. In addition, the method of treatment application and parameters used may influence the effectiveness of deep oscillation therapy. Strength of Recommendation: Level B.
Heidi A. Wayment, Ann H. Huffman, Monica Lininger and Patrick C. Doyle
Social network analysis (SNA) is a uniquely situated methodology to examine the social connections between players on a team, and how team structure may be related to self-reported team cohesion and perceived support for reporting concussion symptoms. Team belonging was positively associated with number of friendship ties (degree; r = .23, p < .05), intermediate ties between teammates (betweenness; r = .21, p < .05), and support from both teammates (r = .21, p < .05) and important others (r = .21, p < .05) for reporting concussion symptoms. Additionally, an SNA-derived measure of social influence, eigenvector centrality, was associated with football identity (r = .34, p < .01), and less support from important others (r = –.24, p < .05) regarding symptom reporting. Discussion focuses on why consideration of social influence dynamics may help improve concussion-related education efforts.