Functional assessments of foot strength: a comparative and repeatability study.

BACKGROUND: Evaluating the strength of the small muscles of the foot may be useful in a variety of clinical applications but is challenging from a methodology standpoint. Previous efforts have focused primarily on the functional movement of toe flexion, but clear methodology guidelines are lacking. A novel foot doming test has also been proposed, but not fully evaluated. The purposes of the present study were to assess the repeatability and comparability of several functional foot strength assessment techniques. METHODS: Forty healthy volunteers were evaluated across two testing days, with a two-week doming motion practice period between them. Seven different measurements were taken using a custom toe flexion dynamometer (seated), custom doming dynamometer (standing), and a pressure mat (standing). Measurements from the doming dynamometer were evaluated for reliability (ICCs) and a learning effect (paired t-tests), while measurements from the toe flexion dynamometer and pressure mat were evaluated for reliability and comparability (correlations). Electromyography was also used to descriptively assess the extent of muscle isolation in all measurements. RESULTS: Doming showed excellent within-session reliability (ICCs > 0.944), but a clear learning effect was present, with strength (p < 0.001) and muscle activity increasing between sessions. Both intrinsic and extrinsic muscles were engaged during this test. All toe flexion tests also showed excellent reliability (ICCs > 0.945). Seated toe flexion tests using the dynamometer were moderately correlated to standing toe flexion tests on a pressure mat (r > 0.54); however, there were some differences in muscle activity. The former may better isolate the toe flexors, while the latter appeared to be more functional for many pathologies. On the pressure mat, reciprocal motion appeared to display slightly greater forces and reliability than isolated toe flexion. CONCLUSIONS: This study further refines potential methodology for foot strength testing. These devices and protocols can be duplicated in the clinic to evaluate and monitor rehabilitation progress in clinical populations associated with foot muscle weakness.

Academic Difficulty and Vision Symptoms in Children with Concussion.

PURPOSE: Academic difficulty is reported in children with prolonged post-concussive symptoms. Despite growing evidence that vestibular-ocular and vision-specific dysfunction are common in children after concussion, vision is rarely mentioned in return-to-learn protocols. The purpose of this project was to evaluate a cohort of children with prolonged post-concussive symptoms to determine if vision symptoms are associated with those reporting academic difficulty. METHODS: Data were obtained from the Children's of Alabama Concussion Clinic REDCap dataset from the period January 2007 to October 2013. From this dataset of 1033 concussion events, a cohort of 276 children aged 5 to 18 years with three or more concussion-related symptoms present for 10 days or more was identified. A cross-sectional cohort study was undertaken to evaluate the association of concussion symptoms, SCAT2 scores, and demographic and concussion severity markers to reported educational difficulty among children with prolonged post-concussive symptoms. Univariate and multivariate logistic regression techniques were used to model the association of reported educational difficulty to self-reported vision abnormalities. RESULTS: Mean age was 13.8 years. Median time since the concussive event was 21 days, with 33% (95/276) reporting their concussion more than 30 days before data collection. Academic difficulty was reported by 29% (79/270) and vision abnormalities in 46% (128/274). After model reduction, vision symptoms (OR 2.17, 95% CI 1.02, 4.62), hearing disturbance (OR 2.39, 95% CI 1.06, 5.36), and concentration difficulty (OR 21.62, 95% CI 9.50, 44.47) remained associated with academic difficulty. For those with symptoms 30 days or more after concussion, only vision (OR 3.15, 95% CI 1.06, 9.38) and concentration difficulty (OR 15.33, 95% CI 4.99, 47.05) remained statistically significant. CONCLUSIONS: Vision problems were commonly reported in children with concussions and were independently associated with those reporting academic difficulty. Comprehensive vision assessment should be considered in children reporting academic difficulty and in the development of return-to-learn protocols.

King-Devick and Pre-season Visual Function in Adolescent Athletes.

PURPOSE: The King-Devick test (KD) has been studied as a remove-from-play sideline test in college-age athletes and older; however, studies in younger athletes are limited. A cross-sectional study of the KD and other vision correlates was completed on school-aged athletes during pre-season physicals for a variety of sports to determine the repeatability of the KD. The study also evaluated how convergence, alignment, or pupil function contributed to a slower King-Devick baseline reading. METHODS: Seven hundred eighty-five athletes underwent vision screenings in a hospital or school setting by trained/certified staff as part of pre-season physicals. Six hundred nineteen had KD testing completed per the manufacturer's suggested protocol and repeated. Other baseline vision testing included visual acuity, Modified Thorington testing for alignment, convergence testing, and pupil function using the NeurOptics (NPI-200) NPi. RESULTS: The mean fastest, error-minimized KD time for all participants was 43.9 seconds(s) (SD ± 11.6, range 24-120). Median KD time got faster (+) with age (p < 0.0001). The inter-class correlation coefficient for all scores was 0.92. The absolute mean time difference for any two tests was 3.5 s (SD ± 2.5, range 0-23). There was no association between the best KD time and reduced NPC (p = 0.63), Modified Thorington measure of alignment (p = 0.55), or NPi pupil function (p = 0.79). The Bland Altman repeated measure limits of agreement was ±6.5 seconds for those in the 10th to12th grades, and ±10.2 seconds for those in the 6th to 9th grades. CONCLUSIONS: King-Devick score in junior high and high school athletes is variable but gets faster and more repeatable with increasing age. The KD does not correlate significantly with reduced convergence, alignment, or pupil function. Based on grouped data, a slowing of 10 seconds for younger athletes and 6 seconds for older athletes on a second administration represents a true difference in testing speed. Within-player variability should be considered when removal-from-play decisions are influenced by KD results.

Predictors of delayed recovery following pediatric sports-related concussion: a case-control study.

OBJECT Pediatric sports-related concussions are a growing public health concern. The factors that determine injury severity and time to recovery following these concussions are poorly understood. Previous studies suggest that initial symptom severity and diagnosis of attention deficit hyperactivity disorder (ADHD) are predictors of prolonged recovery (> 28 days) after pediatric sports-related concussions. Further analysis of baseline patient characteristics may allow for a more accurate prediction of which patients are at risk for delayed recovery after a sports-related concussion. METHODS The authors performed a single-center retrospective case-control study involving patients cared for at the multidisciplinary Concussion Clinic at Children's of Alabama between August 2011 and January 2013. Patient demographic data, medical history, sport concussion assessment tool 2 (SCAT2) and symptom severity scores, injury characteristics, and patient balance assessments were analyzed for each outcome group. The control group consisted of patients whose symptoms resolved within 28 days. The case group included patients whose symptoms persisted for more than 28 days. The presence or absence of the SCAT2 assessment had a modifying effect on the risk for delayed recovery; therefore, stratum-specific analyses were conducted for patients with recorded SCAT2 scores and for patients without SCAT2 scores. Unadjusted ORs and adjusted ORs (aORs) for an association of delayed recovery outcome with specific risk factors were calculated with logistic regression analysis. RESULTS A total of 294 patients met the inclusion criteria of the study. The case and control groups did not statistically significantly differ in age (p = 0.7). For the patients who had received SCAT2 assessments, a previous history of concussion (aOR 3.67, 95% CI 1.51-8.95), presenting SCAT2 score < 80 (aOR 5.58, 95% CI 2.61-11.93), and female sex (aOR 3.48, 95% CI 1.43-8.49) were all associated with a higher risk for postconcussive symptoms lasting more than 28 days. For patients without SCAT2 scores, female sex and reporting a history of ADHD significantly increased the odds of prolonged recovery (aOR 4.41, 95% CI 1.93-10.07 and aOR 3.87, 95% CI 1.13-13.24, respectively). Concussions resulting from playing a nonhelmet sport were also associated with a higher risk for prolonged symptoms in patients with and without SCAT2 scores (OR 2.59, 95% CI 1.28-5.26 and OR 2.17, 95% CI 0.99-7.73, respectively). Amnesia, balance abnormalities, and a history of migraines were not associated with symptoms lasting longer than 28 days. CONCLUSIONS This case-control study suggests candidate risk factors for predicting prolonged recovery following sports-related concussion. Large prospective cohort studies of youth athletes examined and treated with standardized protocols will be needed to definitively establish these associations and confirm which children are at highest risk for delayed recovery.

Establishment of a multidisciplinary concussion program: impact of standardization on patient care and resource utilization.

OBJECT: Recent legislation and media coverage have heightened awareness of concussion in youth sports. Previous work by the authors' group defined significant variation of care in management of children with concussion. To address this variation, a multidisciplinary concussion program was established based on a uniform management protocol, with emphasis on community outreach via traditional media sources and the Internet. This retrospective study evaluates the impact of standardization of concussion care and resource utilization before and after standardization in a large regional pediatric hospital center. METHODS: This retrospective study included all patients younger than 18 years of age evaluated for sports-related concussion between January 1, 2007, and December 31, 2011. Emergency department, sports medicine, and neurosurgery records were reviewed. Data collected included demographics, injury details, clinical course, Sports Concussion Assessment Tool-2 (SCAT2) scores, imaging, discharge instructions, and referral for specialty care. The cohort was analyzed comparing patients evaluated before and after standardization of care. RESULTS: Five hundred eighty-nine patients were identified, including 270 before standardization (2007-2011) and 319 after standardization (2011-2012). Statistically significant differences (p < 0.0001) were observed between the 2 groups for multiple variables: there were more girls, more first-time concussions, fewer initial presentations to the emergency department, more consistent administration of the SCAT2, and more consistent supervision of return to play and return to think after adoption of the protocol. CONCLUSIONS: A combination of increased public awareness and legislation has led to a 5-fold increase in the number of youth athletes presenting for concussion evaluation at the authors' center. Establishment of a multidisciplinary clinic with a standardized protocol resulted in significantly decreased institutional resource utilization and more consistent concussion care for this growing patient population.