Discriminating Between Copers and those with Chronic Ankle Instability with Clinical Outcomes

Introduction: Chronic ankle instability (CAI) is a common consequence of lateral ankle sprains and a leading cause of post-traumatic ankle osteoarthritis. Despite a history of a lateral ankle sprain, there are some individuals (copers) who appear to have a mechanism that allows them to avoid recurrent lateral ankle sprains and giving way episodes. To date, research has identified differences in perceptual (e.g. self-assessed disability), mechanical (e.g. ligament laxity), and sensorimotor (e.g. balance) outcomes between copers and those with CAI. However, the vast majority of these outcomes are considered research and/or laboratory based and thus impractical for most clinicians to use on a daily basis. The identification of clinical tools, capable of discriminating between copers and those with CAI is the first step in developing an accurate clinical battery of tests that can be used to predict patients more likely to develop CAI after an initial lateral ankle sprain. Therefore, the purpose of this investigation was to establish the ability of clinical outcome measures to discriminate between copers and those with CAI. Methods: Participants- A total of 46 participants (21 copers and 25 with CAI) were enrolled and completed the investigation. All participants read and signed the university approved informed consent document prior to participation. All subjects were between the ages of 18-30 and participated in recreational activity for at least 90 minutes each week. Copers and those with CAI had a history of at least one moderate to severe ankle sprain that required acute care. Copers resumed all pre-injury activity without limitation and without recurrent episodes of injury/giving way for at least 12 months prior to testing and scored \u3e24 on the ankle joint functional assessment tool (AJFAT). In comparison, those with CAI had at least one recurrent sprain within 6 months of testing and scored \u3c20 on the AJFAT. Protocol: Perceptual outcomes, the Foot Ankle Ability Measure (FAAM) and FAAM Sport (FAAM-S) were completed first. These questionnaires determine a subject’s self-assessed limitations during daily and physical activities and lower scores represent greater disability. Next, mechanical adaptations were assessed via the the weight bearing lunge test (WBLT) and talar glide test. The WBLT measured ankle dorsiflexion range of motion using a modified lunge technique. Maximum dorsiflexion was defined as the furthest distance the subject’s foot could be from a wall while the subject’s knee was in contact with the wall and the subject’s heel was flat on the ground. The talar glide test measures the magnitude of the talus’ posterior glide by measuring the change in passive knee flexion, from 90°, while an examiner simultaneously pushes the talus posteriorly and pulls the foot into dorsiflexion until the point of capsular restriction. Finally, sensorimotor dysfunction was assessed with the Star Excursion Balance Test (SEBT) and isometric strength testing. The SEBT is a measure of dynamic postural control and measures the distance a subject can reach with their contralateral leg without losing their balance. Reach distance was defined as the farthest point that an individual could touch without accepting weight on their reach leg and maintaining balance through the return to a bilateral stance. Reach distance was normalized to each subject’s leg length. Using a handheld dynamometer, ankle dorsiflexion, plantar flexion, eversion, and inversion strength was assessed during 3-second maximal contractions. Strength was normalized to a subject’s body weight. Statistical Analysis: Group differences in perceptual, mechanical, and sensorimotor outcomes were assessed with independent sample t-tests. If significance was achieved, the ability of an outcome to accurately discriminate between the groups was then assessed using the area under the curve (AUC) for receiver operating characteristic (ROC) curves. A ROC curve illustrates the “trade-off” between sensitivity and specificity throughout a measure’s entire range of values. Finally, clinical meaningfulness was established by the calculation of cut-off scores and likelihood ratios for outcomes that successfully discriminated between copers and those with CAI. A traditional level of significance (=0.05) was used for all analyses. RESULTS: The CAI group had significant perceptual and sensorimotor deficits relative to the coper group. Specifically, FAAM (Coper: 99.0±2.5%, CAI: 89.2±9.5%), FAAM-S (Coper: 96.6±4.1%, CAI: 79.3±16.2%), normalized posteriomedial SEBT reach distance (Coper: 91.2±8.1%, CAI: 83.5±6.5%), and normalized dorsiflexion strength (Coper: 74.5±19.9%, CAI: 62.9±12.8%) were lower in those with CAI relative to copers. The secondary analysis revealed that the FAAM (P\u3c0.01), FAAM-S (p\u3c0.01), and posteriomedial SEBT reach distance (p\u3c0.01) accurately discriminated between copers and those with CAI. The AUC scores, cut-off scores, and likelihood ratios can be seen in the table below. No differences existed with regards to talar glide, range of motion, anterior SEBT reach, posteriolateral SEBT reach, and normalized eversion, inversion, or plantar flexion strength. Outcome Measure Category AUC Cut-off Score Likelihood Ratios (95% Confidence Intervals) Positive Negative FAAM 0.93 99% 5.05 (2.92 to 10.36) 0.05 (0.01 to 0.21) FAAM-S 0.90 88% 31.00 (4.42 to 217.67) 0.33 (0.22 to 0.51) Posteriomedial SEBT Reach 0.79 89% 2.53 (1.77 to 3.79) 0.06 (0.02 to 0.27) DISCUSSION: The results of this investigation indicate that perceptual (FAAM, FAAM-S) and some sensorimotor outcomes (posteriomedial SEBT reach distance) can discriminate between copers and those with CAI. We hypothesize that these outcome measures represent part of the mechanism that 1) allows copers to function as if uninjured and 2) is absent in individuals who develop CAI. The current results, using clinical outcome measures, support previous findings that have illustrated perceptual and sensorimotor deficits using research and/or laboratory based outcomes. Further, because a variety of the current outcomes (perceptual and sensorimotor) successfully discriminated between copers and those with CAI, groups, the current findings support the theory that the causal mechanism of CAI is multi-factorial in nature. However, the most important finding of the current investigation is that the perceptual outcomes demonstrated the greatest ability to discriminate between copers and those with CAI with accuracy point estimates ranging from 0.90-0.93. Indeed, the perceptual outcomes (as a whole) demonstrated higher AUC estimates and positive likelihood ratios, as well as lower negative likelihood ratios compared with the sensorimotor outcomes (as a whole). This finding, which supports previous results, indicates that perceptual outcomes have the greatest ability to accurately predict those who became copers after initial lateral ankle sprain. Given the magnitude of the positive and negative likelihood ratios, we believe that perception based outcomes, such as the FAAM and FAAM-S, should be used in future longitudinal research investigations designed to determine if and when, post-injury, these outcomes can predict who will develop CAI after an initial lateral ankle sprain

Sensory-Targeted Ankle Rehabilitation Strategies for Chronic Ankle Instability

Deficient sensory input from damaged ankle ligament receptors is thought to contribute to sensorimotor deficits in those with chronic ankle instability (CAI). Targeting other viable sensory receptors may then enhance sensorimotor control in these patients. The purpose of this randomized controlled trial was to evaluate the effects of 2 weeks of sensory-targeted rehabilitation strategies (STARS) on patient- and clinician-oriented outcomes in those with CAI

Predicting Manual Therapy Treatment Success in Patients With Chronic Ankle Instability: Improving Self-Reported Function

CONTEXT: Therapeutic modalities that stimulate sensory receptors around the foot-ankle complex improve chronic ankle instability (CAI)-associated impairments. However, not all patients have equal responses to these modalities. Identifying predictors of treatment success could improve clinician efficiency when treating patients with CAI. OBJECTIVE: To conduct a response analysis on existing data to identify predictors of improved self-reported function in patients with CAI. DESIGN: Secondary analysis of a randomized controlled clinical trial. SETTING: Sports medicine research laboratories. PATIENTS OR OTHER PARTICIPANTS: Fifty-nine patients with CAI, which was defined in accordance with the International Ankle Consortium recommendations. INTERVENTION(S): Participants were randomized into 3 treatment groups (plantar massage [PM], ankle-joint mobilization [AJM], or calf stretching [CS]) that received six 5-minute treatments over 2 weeks. MAIN OUTCOME MEASURE(S): Treatment success, defined as a patient exceeding the minimally clinically important difference of the Foot and Ankle Ability Measure-Sport (FAAM-S). RESULTS: Patients with ≤5 recurrent sprains and ≤82.73% on the Foot and Ankle Ability Measure had a 98% probability of having a meaningful FAAM-S improvement after AJM. As well, ≥5 balance errors demonstrated 98% probability of meaningful FAAM-S improvements from AJM. Patients <22 years old and with ≤9.9 cm of dorsiflexion had a 99% probability of a meaningful FAAM-S improvement after PM. Also, those who made ≥2 single-limb-stance errors had a 98% probability of a meaningful FAAM-S improvement from PM. Patients with ≤53.1% on the FAAM-S had an 83% probability of a meaningful FAAM-S improvement after CS. CONCLUSIONS: Each sensory-targeted ankle-rehabilitation strategy resulted in a unique combination of predictors of success for patients with CAI. Specific indicators of success with AJM were deficits in self-reported function, single-limb balance, and <5 previous sprains. Age, weight-bearing-dorsiflexion restrictions, and single-limb balance deficits identified patients with CAI who will respond well to PM. Assessing self-reported sport-related function can identify CAI patients who will respond positively to CS

Altered dynamic postural control during gait termination following concussion

Impaired postural control is a cardinal symptom following concussion. Planned gait termination (GT) is a non-novel, dynamic task that challenges postural control in individuals with neurological deficits, and it could be an impactful measure for identifying dynamic postural control impairments following concussion. Therefore, the purpose of this study was to assess acute post-concussion dynamic postural control utilizing a planned GT task. The concussion participants (n= 19, age: 19.0 ± 0.8 years, height: 177.0 ± 10.1 cm, weight: 83.3 ± 20.0 kg) completed five planned GT trials during preseason baseline testing (Baseline) and on Day 1 post-concussion (Day-1). Healthy control participants (n=19, age: 20.4 ± 1.2 years, height: 173.8 ± 8.9 cm, weight: 80.2 ± 17.6 kg) completed the same trials a week apart. The dependent variables of interest included COP displacement and velocity in the mediolateral (ML) and anteroposterior (AP) axes during the three phases (braking, transitional, stabilization) of planned GT. There were significant interactions observed in both the braking ML and transitional AP displacement (p= 0.042, p= 0.030) and velocity (p= 0.027, p= 0.030). These results suggest a conservative post-concussion motor control strategy during planned GT. Further, these results support the use of dynamic postural control tasks as measures of post-concussion impairments

Incidence and Cost of Ankle Sprains in United States Emergency Departments

Ankle sprains represent a common injury in emergency departments, but little is known about common complications, procedures, and charges associated with ankle sprains in emergency departments

Selection criteria for patients with chronic ankle instability in controlled research: a position statement of the International Ankle Consortium

While research on chronic ankle instability (CAI) and awareness of its impact on society and health care systems has grown substantially in the last 2 decades, the inconsistency in participant or patient selection criteria across studies presents a potential obstacle to addressing the problem properly. This major gap within the literature limits the ability to generalize this evidence to the target patient population. Therefore, there is a need to provide standards for patient or participant selection criteria in research focused on CAI with justifications using the best available evidence. The International Ankle Consortium provides this position paper to present and discuss an endorsed set of selection criteria for patients with CAI based on the best available evidence to be used in future research and study designs. These recommendations will enhance the validity of research conducted in this clinical population with the end goal of bringing the research evidence to the clinician and patient

Sensory-targeted ankle rehabilitation strategies for chronic ankle instability

Introduction Deficient sensory input from damaged ankle ligament receptors is thought to contribute to sensorimotor deficits in those with chronic ankle instability (CAI). Targeting other viable sensory receptors may then enhance sensorimotor control in these patients. The purpose of this randomized controlled trial was to evaluate the effects of 2 wk of sensory-targeted ankle rehabilitation strategies (STARS) on patient- and clinician-oriented outcomes in those with CAI. Methods Eighty patients with self-reported CAI participated. All patients completed patient-oriented questionnaires capturing self-reported function as well as the weight-bearing lunge test and an eyes-closed single-limb balance test. After baseline testing, patients were randomly allocated to four STARS groups: joint mobilization, plantar massage, triceps surae stretching, or control. Each patient in the intervention groups received six 5-min treatments of their respective STARS over 2 wk. All subjects were reassessed on patient- and clinician-oriented measures immediately after the intervention and completed a 1-month follow-up that consisted of patient-oriented measures. Change scores of the three STARS groups were compared with the control using independent t-tests and Hedges\u27 g effect sizes with 95% confidence intervals. Results The joint mobilization group had the greatest weight-bearing lunge test improvement. Plantar massage had the most meaningful single-limb balance improvement. All STARS groups improved patient-oriented outcomes with joint mobilization having the most meaningful effect immediately after the intervention and plantar massage at the 1-month follow-up. Conclusion Each STARS treatment offers unique contributions to the patient- and clinician-oriented rehabilitation outcomes of those with CAI. Both joint mobilization and plantar massage appear to demonstrate the greatest potential to improve sensorimotor function in those with CAI

The effect of sensory-targeted ankle rehabilitation strategies on single-leg center of pressure elements in those with chronic ankle instability: A randomized clinical trial

© 2018 Sports Medicine Australia Objectives: To determine the effects of sensory-targeted ankle rehabilitation strategies on laboratory-oriented measures of single-leg balance in those with chronic ankle instability. Design: Non-inferiority randomized controlled trial. Methods: Seventy-seven participants with self-reported chronic ankle instability were randomized into 4 treatment groups: Ankle joint mobilization, plantar massage, triceps surae stretching, and a control group. All participants performed 3 trials of single-leg balance on a force plate with eyes open and closed at 3 time points (baseline, immediately after the first treatment, and following 6 treatments over 2 weeks). The spatial (standard deviation), temporal (velocity), and spatiotemporal (time-to-boundary) elements of center of pressure excursions in single-leg balance were evaluated with eyes open and eyes closed at each time point. Immediate and final change scores were calculated for each group from the baseline values on these variables. Results: Joint mobilization produced immediate improvements in the temporal elements with eyes open and closed that exceeded the minimum detectable changes for these measures. Plantar massage and triceps surae stretching also enhanced the temporal element after a single treatment, but only with eyes closed. No substantial benefit of any of the interventions were found after 2-weeks of treatment, regardless of treatment group. Conclusions: Sensory-targeted ankle rehabilitation strategies substantially improve single-leg postural control after one treatment, but these changes are short-lived. Future research is needed to determine whether combinations of sensory-targeted ankle rehabilitation strategies with other therapeutic interventions potentially improve single-leg balance stability in those with CAI compared to use in isolation. Clinical trial registration number: NCT01541657