Ryan S. McCann

Prediction of Lateral Ankle Sprains in Football Players Based on Clinical Tests and Body Mass Index

Background: The lateral ankle sprain (LAS) is the most common injury suffered in sports, especially in football. While suggested in some studies, a predictive role of clinical tests for LAS has not been established. Purpose: To determine which clinical tests, focused on potentially modifiable factors of movement patterns and body mass index (BMI), could best demonstrate risk of LAS among high school and collegiate football players. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 539 high school and collegiate football players were evaluated during the preseason with the Star Excursion Balance Test (SEBT) and Functional Movement Screen as well as BMI. Results were compared between players who did and did not suffer an LAS during the season. Logistic regression analyses and calculated odds ratios were used to determine which measures predicted risk of LAS. Results: The LAS group performed worse on the SEBT–anterior reaching direction (SEBT-ANT) and had higher BMI as compared with the noninjured group (P < .001). The strongest prediction models corresponded with the SEBT-ANT. Conclusion: Low performance on the SEBT-ANT predicted a risk of LAS in football players. BMI was also significantly higher in football players who sustained an LAS. Identifying clinical tools for successful LAS injury risk prediction will be a critical step toward the creation of effective prevention programs to reduce risk of sustaining an LAS during participation in football.

Therapeutic interventions for improving self-reported function in patients with chronic ankle instability: a systematic review

Objective To identify which therapeutic intervention may be most effective for improving self-reported function in patients with chronic ankle instability (CAI). Design Systematic literature review. Articles were appraised using the Downs and Black Checklist by 3 reviewers. Data sources PubMed along with CINAHL, MEDLINE and SPORTDiscus within EBSCOhost for pertinent articles from their inception through August 2016. Eligibility criteria for selected studies Articles included were required to (1) be written in English, (2) report adequate data to calculate effect sizes, (3) identify patients with CAI, (4) use some form of therapeutic intervention and (5) use a self-reported questionnaire as a main outcome measurement. Results A broad spectrum of therapeutic interventions were identified related to balance training, multimodal rehabilitation, joint mobilisation, resistive training, soft-tissue mobilisation, passive calf stretching and orthotics. All of the articles included in the balance training category had moderate-to-strong Hedges g with none of the 95% CIs crossing 0. Hedges g effect sizes ranged from −0.67 to −2.31 and −0.51 to −1.43 for activities of daily living and physical activity, respectively. The multimodal rehabilitation category also produced moderate-to-strong Hedges g effect sizes but with large CIs crossing 0. Hedges g effect sizes ranged from −0.47 to −9.29 and −0.62 to −24.29 for activities of daily living and physical activity, respectively. Conclusions The main findings from this systematic review were balance training provided the most consistent improvements in self-reported function for patients with CAI.

Potential Corticomotor Plasticity in Those with and without Chronic Ankle Instability

Introduction Quantifying corticomotor alterations is important to understand the neurophysiological mechanisms that likely contribute to the neuromuscular control deficits observed in patients with chronic ankle instability (CAI). Corticomotor output mapping provides further insight into the changes within the motor cortex and identifies potential changes in the area of the motor cortex associated with selected muscles. Therefore, this investigation compared the corticomotor map output for the fibularis longus (FL) muscle in patients with and without CAI. Methods Eighteen CAI patients and 16 healthy controls (HC) volunteered. Transcranial magnetic stimulation was used to map the motor cortex’s representation of the FL. The normalized average of three motor evoked potentials at 100% of active motor threshold intensity was recorded for each scalp site on a 6 × 6 cm grid. Corticomotor output map was compared between groups through 1) the size of the corticomotor map area, 2) the volume of the corticomotor map, and 3) the location of cortical representation. Independent t-tests were used to assess group differences in each mapping outcome variable. Cohen’s d effect sizes along with 95% confidence intervals were calculated using the pooled SD values. Results CAI patients exhibited less map volume (P = 0.018, CAI = 8.2 ± 3.2 cm2 mV vs HC = 11.3 ± 3.9 cm2 mV) and map area (P = 0.046, CAI = 12.8 ± 6.0 cm2 vs HC: 17.4 ± 6.9 cm2) compared with HC. Conclusions The smaller map area and volume suggest a more concentrated area of neurons communicating with the FL muscle in patients with CAI. Consequently, motor cortical cells on the border of the FL excitation area are less committed to the proper function of the FL muscle and may be recruited by other surrounding areas. This may explain altered movement strategies that lead to ankle reinjury.

Associations between Functional and Isolated Performance Measures in Collegiate Women’s Soccer Players

CONTEXT The Star Excursion Balance Test (SEBT) and Functional Movement Screen (FMS) are functional performance measures capable of predicting lower-extremity injury risk. While suboptimal SEBT and FMS performances are influenced by multiple factors, the contribution of hip strength and flexibility to these tests is mostly unknown. Examination of hip strength and flexibility influences on the SEBT and FMS may direct clinicians to better methods of correcting functional deficits. OBJECTIVE Determine the relationships of isometric hip strength and hip passive range of motion (PROM) with functional performance measures. DESIGN Cross-sectional. SETTING Athletic training facility. PARTICIPANTS 43 NCAA Division I womens soccer players (19.65 ± 1.12 y; 166.93 ± 3.84 cm; 60.99 ± 4.31 kg) volunteered. DATA COLLECTION AND ANALYSIS All participants were tested bilaterally in the SEBT; the deep squat, in-line lunge, hurdle step, and straight leg raise, comprising a lower-extremity FMS (FMS-LE); hip internal and external rotation PROM; and isometric hip extension strength (HEXT). The mean of the 3 averaged, normalized SEBT scores was used as a composite score. Pearson product moment correlations assessed relationships of SEBT and FMS-LE scores with PROM and HEXT. Significance was set a priori at P < .05. RESULTS Pearson correlations revealed anterior (ANT) SEBT scores had a low negative association with HEXT (r = -0.33,P = .004) and a low positive association with hip internal rotation PROM (PROM-IR) (r = .43,P = .003). All other correlations were negligible. CONCLUSIONS Flexibility training aimed at PROM-IR may contribute to improved ANT scores. Targeting HEXT and hip external rotation PROM are likely not preferred means of correcting deficits in SEBT and FMS-LE performance.

Variations in Star Excursion Balance Test Performance Between High School and Collegiate Football Players.

Abstract McCann, RS, Kosik, KB, Beard, MQ, Terada, M, Pietrosimone, BG, and Gribble, PA. Variations in Star Excursion Balance Test performance between high school and collegiate football players. J Strength Cond Res 29(10): 2765–2770, 2015—The Star Excursion Balance Test (SEBT) is a reliable inexpensive tool used to assess dynamic postural control deficits and efficacy in the prediction of musculoskeletal injuries, but with little previous consideration for performance differences across age and skill levels. The purpose of this study was to examine differences in SEBT scores between high school and collegiate football players. Three-hundred eighteen high school football players and 180 National Collegiate Athletic Association Division I collegiate football players volunteered to participate. Star Excursion Balance Test scores were obtained bilaterally for anterior (ANT), posterolateral (PL), and posteromedial (PM) directions, and for an overall composite (COMP) score. The mean of 3 trials from each leg was normalized to stance leg length and presented as a percentage score. Bilaterally averaged scores were compared between high school and collegiate football players using separate independent t-tests. A multiple linear backward regression determined the amount of variance in SEBT scores explained by age, mass, and height. Compared with collegiate athletes, high school athletes had lower PL (72.8 ± 11.4% vs. 77.1 ± 10.2%; p < 0.001), PM (83.5 ± 10.2% vs. 86.7 ± 10.7%; p = 0.001), and COMP (75.4 ± 8.5% vs. 78.0 ± 7.4%; p = 0.001) scores. Anterior scores did not differ between high school (69.9 ± 7.9%) and collegiate (70.3 ± 7.1%) athletes (p = 0.545). Age, mass, and height were not meaningful contributors to ANT (R 2 = 0.089; p < 0.001), PL (R 2 = 0.032; p < 0.001), PM (R 2 = 0.030; p = 0.002), and COMP (R 2 = 0.048; p < 0.001) variances. Disparity between high school and collegiate athletes should be considered when using the SEBT to identify risk of or deficits related to lower extremity injury in football players.

Resilience and Self-Efficacy: A Theory-Based Model of Chronic Ankle Instability

Chronic ankle instability (CAI) commonly develops after a lateral ankle sprain (LAS). Widespread residual complaints suggest that rehabilitation provided for many LAS is insufficient. We propose a theoretical model for CAI development impacted by patient resilience and self-efficacy, social constructs, and rehabilitation adherence. An exclusive social structure within team sports often acts as an important support system to those within it, but may allow individuals to rationalise placing oneself at elevated risk of injury for the team’s benefit. Social attitudes may lower perceived control of patients (decreased resilience), making them feel less capable of carrying out a course of action (decreased self-efficacy), such as rehabilitation. Highly resilient student-athletes may communicate a need or desire for extensive care. Greater self-efficacy can facilitate patients’ insistence for thorough care, which may further boost resilience and self-efficacy, improving rehabilitation adherence, and decreasing the prevalence of CAI. Due to the perceived benign nature of LAS in the general population, many rely on self-treatment or emergency department recommendations involving rudimentary treatment methods that may not address all underlying deficits, nor prevent recurrent LAS. Although deficiencies in postural control, gait, and other functional tasks are commonly reported in CAI populations, these deficits often do not receive adequate attention during rehabilitation. However, the supervision of a clinician specialising in the management of sport-related musculoskeletal injuries will improve the quality and breadth of rehabilitation needed to address the host of potential deficits that arise from a LAS. Resilience, self-efficacy, and social constructs, in addition to clinician expertise, can affect injury outcomes, and should be considered and promoted in each patient through goal setting, buddy systems, and flexible scheduling. Legislation outlining rights of student-athletes may further affect psychosocial influences. Ultimately, elevated patient resilience and self-efficacy in LAS patients may facilitate rehabilitation adherence, reducing CAI development.

O12 Prediction of recurrent injury following return-to-play from an ankle sprain

Study Design Prospective cohort study. Objectives Determine the ability of clinical outcomes and anthropometrics to predict recurrent injuries in athletes during the same competitive season following return-to-play (RTP) from an ankle sprain. Background Prediction of recurrent injury may be a valuable step towards minimising long-term consequences of ankle sprains. Limited investigation has predicted single-season recurrent ankle sprains in competitive athletes. Methods and Measures We evaluated 60 high school and collegiate athletes at RTP following an ankle sprain (F:17, M:43; 17.9±3.3 years; 178.6±10.8 cm; 85.0±24.8 kg). Clinical outcomes included pain (100 mm visual analogue scale), swelling (figure-of-eight girth measurement), dorsiflexion ROM (weight-bearing lunge test), ligamentous laxity (anterior drawer and talar tilt tests), and the Foot and Ankle Ability Measure activity of daily living (FAAM-ADL) and sport (FAAM-S) subscales. Anthropometric outcomes included height, mass, and body mass index (BMI). After RTP, athletic trainers documented recurrent ankle sprains during the same competitive season. Results Patients with (n=8) and without (n=52) recurrent ankle sprains did not differ in involved-limb pain (12.8±16.1 vs 9.8±13.7, p=0.58), swelling (56.7±4.1 vs 54.4±5.1 cm, p=0.23), dorsiflexion ROM (7.6±4.1 vs 6.9±3.6 cm, p=0.58), FAAM-ADL (85.1±9.1 vs 86.4%±10.8%, p=0.73), and FAAM-S (70.3±10.0 vs 64.8%±19.8%, p=0.44) at RTP. Anterior drawer (p=0.64) and talar tilt (p=0.25) laxity (+/-) was not associated with recurrent injury status. Patients with recurrent ankle sprains had greater height (185.7±9.9 vs 177.5±10.6 cm, p=0.04), mass (104.7±29.7 vs 81.9±22.8 kg, p=0.01), and BMI (30.1±6.7 vs 25.7±5.5 kg/m2, p=0.05) than patients without recurrent ankle sprains. Area under receiver operating characteristic curves (AUROC) and diagnostic odds ratios (DOR) exhibited predictive value for height (AUROC=0.71, DOR=4.93), mass (AUROC=0.75, DOR=12.21) and BMI (AUROC=0.71, DOR=9.48). Conclusions Athletic patients with greater height, mass, and BMI demonstrated greater odds of recurrent ankle sprains in the same competitive season following RTP. Taller and heavier patients may benefit from weight-management education before RTP to prevent recurrent ankle sprains.

P19 Re-examining self-reported instability and injury history to differentiate chronic ankle instability and coper patients

Study Design Case-control study. Objectives To explore self-reported responses for differentiating CAI(chronic ankle instability) and lateral ankle sprain(LAS)-Coper status. Background Self-reported instability and disability in conjunction with patient history have been used to differentiate CAI and LAS-Copers, but certain self-reported evaluation tools, such as the Identification of Functional Ankle Instability (IdFAI), may contain some redundancy. It remains unknown if other potential patient history items in concert with selected items from the IdFAI could create more efficient identification of CAI and LAS-Copers. Methods and Measures Data were extracted from 241 participants enrolled in previous laboratory studies that compared CAI(n=128) and LAS-Coper(n=113) groups classified by the guidelines of the International Ankle Consortium. Responses on each item of the IdFAI were examined, and patients responded if they had received formalised rehabilitation for their previous LAS(Y/N). Chi-square analyses were used to explore response distributions. Results Many of the items on the IdFAI resulted in statistically significant response distributions. Of note, 84% of CAI patients responded their ankle gives way(item#6) at least monthly, while 98.8% of LAS-Copers answered yearly or never(p<0.001). Similarly, 85.8% of CAI patients felt their ankle was unstable at least monthly during sport activity(item#10), while 96.4% of LAS-Copers responded yearly or never(p<0.001). More CAI patients reported using crutches than LAS-Copers (item#4)(p=0.006), but distribution of performing rehabilitation was not significantly different between the cohorts(p=0.06). Conclusions The frequency of giving-way and feeling unstable seems to differentiate CAI versus LAS-Copers effectively, which could be used to focus the categorization of patients with a history of LAS with the deficits that need addressing, while utilisation of crutches and initial rehabilitation was less definitive. Additional exploration on the severity of the previous LAS, and the interactions with utilisation of crutches and participation in rehabilitation is needed to shape future interventions for those with LAS history.

P32 Contributing factors to the identification of functional ankle instability questionnaire in individuals with chronic ankle instability

Study Design Case-Control Study. Objectives To determine the extent that strength, dorsiflexion range of motion (DFROM), self-selected gait velocity and star excursion balance test (SEBT) performance contribute to Identification of Functional Ankle Instability (IdFAI) score variance in individuals with chronic ankle instability (CAI). Background Mechanical and sensorimotor impairments have been well documented and associated with the decreased self-reported instability among individuals with CAI. Yet, little information exists for which mechanical and sensorimotor impairments contribute most to the self-reported instability associated with CAI. Identifying the impairments that contribute to self-reported instability will help direct effective evidence-based rehabilitation strategies. Methods and Measures Based on the International Ankle Consortium guidelines, 30 participants with CAI (24.9±4.7 years; 165.9±9.3 cm; 73.6±15.5 kg) and 29 healthy-controls (HC) (25.4±5.7 ys; 168.8±9.4; 68.5±16.5 kg) volunteered. Primary outcomes included weight-bearing DFROM (cm); dorsiflexion, plantar flexion, knee and hip extension, and hip abduction peak isometric torque (Nm/Kg); self-selected gait velocity (cm/sec); and the average normalised reach distance for the SEBT- anterior (SEBT-A), posteromedial (SEBT-PM), and posterolateral (SEBT-PL) reach directions. Separate Independent T-tests were used to identify group differences. Explanatory variables that significantly correlated with the criterion variable were then entered into a backwards multiple linear regression to predict the variance in self-reported instability. Significance was set a priori at p<0.05. Results Participants with CAI scored higher on the IdFAI and had decreased dorsiflexion, plantar flexion, knee and hip extension torque, self-selected gait velocity, weight-bearing DFROM and normalised SEBT-A and SEBT-PM reach distances compared to HC (p<0.05). The backwards multiple linear regression indicated that lower knee extension torque, SEBT-A and self-selected gait velocity were significantly associated with a higher IdFAI (R2=0.534, p<0.001) score in individuals with CAI. Conclusion Therapeutic interventions that target knee strength, the SEBT-A reach direction, and optimisation of gait performance may be beneficial to treating self-reported instability in those with CAI.

Diaphragm Contractility in Individuals with Chronic Ankle Instability.

INTRODUCTION/PURPOSE Previous investigations have identified impaired trunk and postural stability in individuals with chronic ankle instability (CAI). The diaphragm muscle contributes to trunk and postural stability by modulating the intra-abdominal pressure. A potential mechanism that could help to explain trunk and postural stability deficits may be related to altered diaphragm function due to supraspinal sensorimotor changes with CAI. The purpose of this study was to examine the diaphragm contractility in individuals with CAI and healthy controls. METHODS Twenty-seven participants with self-reported CAI and 28 healthy control participants volunteered. A portable ultrasound unit was used to visualize and measure the right and left hemidiaphragm thickness at the end of resting inspiration and expiration in supine while breathing quietly. The diaphragm movement was imaged and recorded on B-mode ultrasonography. The degree of diaphragm contractility was calculated from the mean of three images from the end of resting inspiration and expiration. Independent t-tests were used to compare the degree of diaphragm thickness of right and left sides between the CAI and the control groups. RESULTS The CAI group had a smaller degree of left hemidiaphragm contractility compared with the control group (P = 0.03). There was no between-group difference in other diaphragm variables. CONCLUSION Individuals with CAI appear to have altered diaphragm contractility, which may be an illustration of diaphragm dysfunction and central nervous system changes in CAI population. The association between CAI and altered diaphragm contractility provides clinicians a more comprehensive awareness of proximal impairments associated with CAI. Future investigation is needed to determine whether altered contractility of the diaphragm contributes to functional impairments, activity limitations, and participant restrictions commonly observed in patients with CAI.