Ankle Stability and Movement Coordination Impairments: Lateral Ankle Ligament Sprains Revision 2021

Predicting the success of multimodal rehabilitation in chronic ankle instability based on patient-reported outcomes

Background

The aim of this study was to identify potential indicators to predict the success of multimodal rehabilitation in chronic ankle instability (CAI) patients based on patient-reported outcomes.

Methods

Sixty patients with self-reported CAI participated. Their demographic information, injury history, and symptoms were recorded. Physical examinations and dynamic posture control tests were performed. The participants underwent sixteen 30-min treatment sessions of multimodal rehabilitation over 8 weeks. Fifty-one patients (85.0%) were available for follow-up after 8 weeks of the intervention. Treatment success was defined based on the participants’ perceived recovery using the global rating of change (GRC). Potential predictor variables were entered into a stepwise logistic regression model to identify variables for the prediction of treatment success.

Results

Forty of 51 participants (78.4%) were considered to have a successful outcome. Of the variables assessed, time since last sprain ≤ 8 months was a predictor of treatment success (p < 0.05). If a patient met the criteria, there was an 88.03% probability of successful multimodal rehabilitation.

Conclusion

A time since the last sprain ≤ 8 months may predict successful patient-reported outcomes after multimodal rehabilitation in CAI patients.

Level of evidence

Prospective study, Level 2.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05676-0.

Comparative Effects of Neuromuscular- and Strength-Training Protocols on Pathomechanical, Sensory-Perceptual, and Motor-Behavioral Impairments in Patients with Chronic Ankle Instability: Randomized Controlled Trial

(1) Background: Chronic ankle instability (CAI) is a complex condition that includes limited mobility, perceived instability, and recurrent ankle sprains are common characteristics that reduce the quality of life in subjects who suffer from CAI. Neuromuscular training and strength training have been recommended in CAI management interventions. However, there are contradictory findings on results when comparing neuromuscular training, strength training, and the control group. The objective of this study was to compare the effectiveness of 8 weeks of neuromuscular intervention training, strength training, and no intervention in a sporting population with reported CAI. (2) Methods: Sixty-seven athletes with CAI were randomly assigned to a neuromuscular training group (NG), strength training group (SG), or control group (CG). Participants completed 8 weeks of neuromuscular training (a combination of static and dynamic exercises), strength training (resistance band exercises), or no training. Outcome measures were assessed at baseline and after 8 weeks and included selfs-reported instability feeling (CAIT), dynamic balance (SEBT), ankle dorsiflexion range of motion (WBLT), and functional status (FAAM and FAAM-SPORT). (3) Results: There were significant differences between strength and control groups in the posteromedial direction of SEBT, FAAM, and FAAM-SPORT after 8 weeks of intervention. (4) Conclusions: Neuromuscular training and strength training based on resistance bands exercises showed significant improvements in ankle dorsiflexion, subjective feeling of instability, functional status, and dynamic balance in patients with CAI.

What do patients referred to physical therapy for a musculoskeletal condition expect? A qualitative assessment

BACKGROUND

Patient expectations related to physical therapy outcomes are commonly collected through surveys and close-ended questionnaires. These methods may not optimally capture patients' expectations for physical therapy, especially in the patients' own words. Louis Gifford identified four questions attempting to guide clinicians' understanding of patients' expectations for physical therapy. However, a qualitative assessment mapping the expectations that patients have prior to starting physical therapy appears to be undocumented.

OBJECTIVES

The aim of this study was to determine patient expectations prior to beginning physical therapy for individuals with musculoskeletal conditions.

DESIGN

Qualitative analysis with structured interviews and open-ended participant responses.

METHODS

Twenty-five people (18 female, 7 male; mean age: 47.04 years) were interviewed prior to their initial physical therapy evaluation using a pragmatic approach rooted in phenomenology. Data were transcribed, coded, and thematized using qualitative data analysis software.

RESULTS

Outcome, education, exercise, evaluation, and cause of pain were key themes expressed by participants. Participants appear to want to better understand their symptoms, how they can improve symptoms, what the clinician will do, and how long they will attend physical therapy. Many participants were not certain where physical therapy fit within their overall healthcare plan, and perceptions of manual therapy were vague.

CONCLUSIONS

These identified themes highlight what patients may expect from a physical therapy experience and clinicians should work to identify and satisfy each patient's individual expectations to optimize outcomes.

Which Functional Tests and Self-Reported Questionnaires Can Help Clinicians Make Valid Return to Sport Decisions in Patients With Chronic Ankle Instability? A Narrative Review and Expert Opinion

Lateral ankle sprain is the most common injury in sports, with up to 40% of patients developing chronic ankle instability (CAI). One possible cause underlying this high rate of recurrence or feeling of giving way may be a premature return to sport (RTS). Indeed, except for time-based parameters, there are no specific criteria to guide clinicians in their RTS decisions in patients with CAI. A recent international consensus highlighted the relevance and importance of including patient-reported ankle function questionnaires combined with functional tests targeting ankle impairments in this population. Thus, the aim of this narrative review and expert opinion was to identify the most relevant functional performance tests and self-reported questionnaires to help clinicians in their RTS decision-making process following recurrent ankle sprains or surgical ankle stabilization. The PubMed (MEDLINE), PEDro, Cochrane Library and ScienceDirect databases were searched to identify published articles. Results showed that the single leg stance test on firm surfaces, the modified version of the star excursion balance test, the side hop test and the figure-of-8 test appeared to be the most relevant functional performance tests to target ankle impairments in patients with CAI. A combination of the Foot and Ankle Ability Measure (FAAM) and the Ankle Ligament Reconstruction-Return to Sport after Injury (ALR-RSI) questionnaires were the most relevant self-reported questionnaires to assess patient function in the context of CAI. Although these functional tests and questionnaires provide a solid foundation for clinicians to validate their RTS decisions in patient with CAI, objective scientific criteria with cut-off scores are still lacking. In addition to the proposed test cluster, an analysis of the context, in particular characteristics related to sports (e.g., fatigue, cognitive constraints), to obtain more information about the patient's risk of recurrent injury could be of added value when making a RTS decision in patients with CAI. In order to evaluate the strength of evertors under ecological conditions, it would also be interesting to assess the ability to control weight-bearing ankle inversion in a unipodal stance. Further studies are needed to assess the relevance of this proposed test cluster in RTS decision-making following lateral ankle sprain injury and CAI.

It Would Take Combat Relevance to Put a Chiropractor in Khakis— This Is Why That Has Not Happened

The purpose of this article is to challenge the premise of a recent commentary suggesting that chiropractors should become commissioned officers. An overview of the early practice guidelines and current scientific evidence for the use of spine and peripheral manipulation is provided. The Military Health System is designed to support military operations and currently includes a large contingent of active duty musculoskeletal healthcare experts to include sports medicine–trained family physicians, orthopedic surgeons, physician assistants/associates, doctors of physical therapy/physical therapists, occupational therapists, and podiatrists. The evidence is clear that it is not in the best interest of our military services to commission alternative practitioners whose practices are out of step with the rest of medicine.

Uneven treadmill training for rehabilitation of lateral ankle sprains and chronic ankle instability: a pragmatic randomized controlled trial (Preprint)

Background

Lateral ankle sprains (LASs) are common injuries among military service members. Approximately 40% of individuals with an LAS progress to develop chronic ankle instability (CAI), a condition that results in substantial mechanical and neurophysiological impairment and activity limitation. Since proprioceptive and balance training improve functional outcomes and prevent secondary injury following LAS, they are recommended in clinical practice. Uneven treadmills are an innovative modality that challenge the sensorimotor system while performing an ecologically valid task simulating environments frequently encountered by service members with LAS and CAI.

Objective

The aim of this study is to evaluate whether the inclusion of uneven treadmill training in standard rehabilitation can improve clinical, functional, biomechanical, and patient-reported outcomes compared with the standard of care alone in service members with LAS and CAI. The prophylactic effects of treatment on secondary injury and identification of any contributing or mediating factors that influence outcomes following treatment will also be evaluated. We hypothesize that service members receiving uneven treadmill training will demonstrate greater improvements in clinical and instrumented measures of impairment, patient-reported function, and lower risk of injury recurrence than the control group immediately post and 18 months following treatment.

Methods

A multisite, parallel randomized clinical trial will be performed among service members aged 18-49 years being treated for LAS and CAI in military treatment facilities in the United States. Participants randomly assigned and allocated to receive the experimental intervention will be provided up to 12 sessions of training on an uneven terrain treadmill over a 6-week treatment course to supplement standard rehabilitation care. Treatment intensity of the rehabilitation exercises and treadmill training will be progressed on the basis of patient-perceived intensity and treatment responses. Outcome measures will include patient-reported outcomes, functional assessments, performance measures, and biomechanical measures. Investigators collecting outcome measures will be blinded to treatment allocation. Reinjury rates and patient-reported outcomes of function will be tracked over 18 months following treatment.

Results

The project was funded in September 2020. Patient recruitment began in November 2021, with 3 participants enrolled as of February 2022. Dissemination of the main study findings is anticipated in 2024.

Conclusions

This study will assess the impact of an innovative uneven-terrain treadmill on treatment outcomes in the rehabilitation of service members with LAS and CAI. The results of this study will be used to inform rehabilitation practices and to potentially improve functional outcomes and secondary prevention in this patient population.

Trial Registration

ClinicalTrials.gov NCT04999904; https://clinicaltrials.gov/ct2/show/NCT04999904?term=NCT04999904

International Registered Report Identifier (IRRID)

DERR1-10.2196/38442

Effects of Midfoot Joint Mobilization on Perceived Ankle–Foot Function in Chronic Ankle Instability: A Crossover Clinical Trial

Context: To investigate the effects of midfoot joint mobilization and a 1-week home exercise program, compared with a sham intervention, and home exercise program on pain, patient-reported outcomes, ankle–foot joint mobility, and neuromotor function in young adults with chronic ankle instability. Design: Crossover clinical trial. Methods: Twenty participants with chronic ankle instability were instructed in a stretching, strengthening, and balance home exercise program and were randomized a priori to receive either midfoot joint mobilizations (forefoot supination, cuboid glide, and plantar first tarsometatarsal) or a sham laying of hands on the initial visit. Changes in foot morphology, joint mobility, strength, dynamic balance, and patient-reported outcomes assessing pain, physical, and psychological function were assessed pre to post treatment and 1 week following post treatment. Participants crossed over to receive the alternate treatment and were assessed pre to post treatment and 1 week following. Linear modeling was used to assess changes in outcomes. Results: Participants demonstrated significantly greater perceived improvement immediately following midfoot mobilization in the single assessment numeric evaluation (sham: 5.0% [10.2%]; mobilization: 43.9% [26.2%]; β: 6.8; P < .001; adj R2: .17; Hedge g: 2.09), and global rating of change (sham: −0.1 [1.1]; mobilization: 1.1 [3.0]; β: 1.8; P = .01; adj R2: .12; Hedge g: 0.54), and greater improved 1-week outcomes in rearfoot inversion mobility (sham: 4.4° [8.4°]; mobilization: −1.6° [6.1°]; β: −6.37; P = .01; adj R2: .19; Hedge g: 0.81), plantar flexion mobility (sham: 2.7° [6.4°]; mobilization: −1.7° [4.3°]; β: −4.36; P = .02; adj R2: .07; Hedge g: 0.80), and posteromedial dynamic balance (sham: 2.4% [5.9%]; mobilization: 6.0% [5.4%]; β: 3.88; P = .04; adj R2: .10; Hedge g: 0.59) compared to the sham intervention. Conclusion: Greater perceived improvement and physical signs were observed following midfoot joint mobilization.

Sensitivity of a Subject-specific Ankle Sprain Simulation to Extrinsic Versus Intrinsic Biomechanical Factors

Ankle sprains are the most common musculoskeletal injury in sport and military activity, despite existing prophylactic strategies. The purpose of this report was to develop a probabilistic simulation of lateral ankle sprains during single-limb drop landing, towards accelerating innovation in ankle sprain prevention. A deterministic, subject-specific musculoskeletal model was extended with automation and probabilistic distributions on sprain-related biomechanical factors. Probabilistic simulations were generated using traditional Monte Carlo techniques and the advanced mean value method, a more computationally-efficient approach. Predicted distributions of peak ankle joint rotations, velocities, and moments borne by supporting passive structures agreed favorably with the deterministic model and with reports of real sprain biomechanics. Parameter sensitivities identified that predictions were most strongly influenced by drop height, subtalar joint posture at contact, invertor/evertor co-activation, and passive ankle stiffness. The advanced mean value method predicted confidence bounds comparable to a 1000-trial Monte Carlo simulation, and required only 14 model evaluations and 4-min processing time. The extended probabilistic simulation may be useful to virtually test new prophylactic strategies for ankle sprains, and is made available for open-source use (https://simtk.org/projects/sprain-sim).

Delayed Rehabilitation Is Associated With Recurrence and Higher Medical Care Use After Ankle Sprain Injuries in the United States Military Health System

OBJECTIVE

To investigate the influence of time taken to begin musculoskeletal rehabilitation on injury recurrence and ankle-related medical care use at 1 year after ankle sprain.

DESIGN

Retrospective cohort study of all beneficiaries of the US Military Health System seeking care for an ankle sprain over a 4-year period.

METHODS

Individuals were classified according to whether they did or did not receive physical rehabilitation. For those who received rehabilitation (n = 6150), linear relationships (with appropriate covariate controls) were analyzed with generalized linear models and generalized additive models to measure the effects of rehabilitation timing on injury recurrence and injury-related medical care use (costs and visits) at 1 year after injury. The nonlinear effect of rehabilitation timing on the probability of recurrence was assessed.

RESULTS

Approximately 1 in 4 people received rehabilitation. The probability of ankle sprain recurrence increased for each day that rehabilitation was not provided during the first week. The probability of ankle sprain recurrence plateaued until about 2 months after initial injury, then increased again, with 2 times greater odds of recurrence compared to those who received physical rehabilitation within the first month. When rehabilitation care was delayed, recurrence (odds ratio [OR] = 1.28), number of foot/ankle-related visits (OR = 1.22), and foot/ankle-related costs increased (OR = 1.13; up to $1400 per episode).

CONCLUSION

The earlier musculoskeletal rehabilitation care started after an ankle sprain, the lower the likelihood of recurrence and the downstream ankle-related medical costs incurred. J Orthop Sports Phys Ther 2021;51(12):619-627. doi:10.2519/jospt.2021.10730.

Celebrating the Achievements of Yet Another Challenging Year

Editor-in-Chief Clare Ardern and JOSPT's editors thank all of those who contributed to JOSPT in 2021. J Orthop Sports Phys Ther 2021;51(12):552-555. doi:10.2519/jospt.2021.0111.

Chronic ankle instability has no correlation with the number of ruptured ligaments in severe anterolateral sprain: a systematic review and meta-analysis

PURPOSE

Despite being a significant public health problem, ankle sprains' prognostic factors are largely unknown. This review aimed to systematically analyze the literature on acute ankle sprains to compare the prognosis of a combined anterior talofibular (ATFL) and calcaneofibular (CFL) ligaments rupture with an isolated ATFL rupture in terms of progression to chronic ankle instability and other clinical outcomes.

METHODS

The databases for Pubmed, CENTRAL and Web of Science were searched. Clinical studies reporting the prognostic effect of combined ATFL-CFL rupture versus an isolated ATFL rupture in conservatively treated ankle sprains, with a minimum follow-up of 12 months, were eligible for inclusion. Only studies with a reliable diagnostic method for anterolateral ankle ligaments evaluation, namely ultrasonography, magnetic resonance imaging, arthrography or stress tenography, were included. The relative risk (RR), along with the 95% confidence interval (CI), was used to quantitatively analyze the main outcomes.

RESULTS

Nine papers were selected for inclusion, of which five were suitable for quantitative analysis. None of them found a statistically significant correlation between ligament injury severity and progression to chronic instability. Concerning other clinical outcomes, three studies found a statistically significant correlation between a combined ligament injury and a worse clinical prognosis. From the quantitative analysis, the relative risk (RR) of chronic ankle instability in a single versus a combined ligament rupture showed no significant difference.

CONCLUSION

A significant statistical correlation between a combined ATFL-CFL rupture and chronic ankle instability, compared to an isolated ATFL rupture, was not found. There is, however, fair evidence showing a worse clinical outcome score in the combined ruptures, as well as a decreased return to full sports activities. The use of reliable and accessible diagnostic methods to determine the number of ruptured ligaments might have a role in managing severe ankle sprains.

LEVEL OF EVIDENCE

Level III.

Responsiveness of the Brazilian IdFAI questionnaire in patients with chronic ankle instability

PURPOSE

This study aimed to determine the responsiveness of the Brazilian version of the Identification of Functional Ankle Instability (IdFAI) questionnaire in students who received an eight-week treatment for chronic ankle instability (CAI).

METHODS

Twenty-five college students (aged 23.12 ± 2.80 years) with CAI, as identified by the IdFAI questionnaire, were recruited. We used distribution and anchor-based methods to assess the responsiveness of the questionnaire, and its ability to determine clinical changes in participants. Eleven anchors were used: Visual Analog Scale for instability (VAS-i); Cumberland Ankle Instability Tool (CAIT); Isometric dorsiflexion, plantar flexion, inversion, and eversion muscle strength measured using a manual dynamometer; Dynamic balance as assessed through the Star Excursion Balance Test (SEBT-Y); Active ankle dorsiflexion range of motion as measured using the weight-bearing lunge test; and Functional performance assessment using three hop tests: single hop, triple crossover hop, and side hop. The distribution-based method used effect size (ES) and standardized response mean (SRM), whereas the anchor-based method used paired t-tests. Both methods allowed the calculation of the minimal important difference (MID).

RESULTS

The Brazilian IdFAI showed high responsiveness, with a large magnitude of change (ES = 1.34) and a high responsiveness index (SRM = 1.28) when assessed after a treatment for CAI. The IdFAI total score (p < .001) and all the 11 anchors [VAS-i (p < .001); CAIT (p < .001); Isometric dorsiflexion (p < .001), plantar flexion (p < .001), inversion (p < .001), and eversion (p < .001) muscle strength; SEBT-Y (p < .001); Lunge test (p = .002); Single hop (p < .001); triple crossover hop (p < .001); and side hop tests (p < .001)] showed significant differences. The anchor and distribution-based methods demonstrated MID values of 3.72 and 1.49-2.27, respectively.

CONCLUSION

The Brazilian IdFAI questionnaire is a patient-reported outcome measure sensitive to clinical changes in individuals with CAI. It can be used as an identification of patients with CAI, and as a parameter to verify clinical changes of clinical trials or therapeutic interventions in the population with CAI.

Fractures and Chronic Recurrence are Commonly Associated with Ankle Sprains: a 5-year Population-level Cohort of Patients Seen in the U.S. Military Health System

BACKGROUND

Whereas ankle-foot injuries are ubiquitous and affect ~16% of military service-members, granularity of information pertaining to ankle sprain subgroups and associated variables is lacking. The purpose of this study was to characterize and contextualize the burden of ankle sprain injuries in the U.S. Military Health System.

METHODS

This was a retrospective cohort study of beneficiaries seeking care for ankle sprains, utilizing data from the Military Health System Data Repository from 2009 to 2013. Diagnosis and procedural codes were used to identify and categorize ankle sprains as isolated lateral, isolated medial, concomitant medial/lateral, unspecified, or concomitant ankle sprain with a malleolar or fibular fracture. Patient characteristics, frequency of recurrence, operative cases, and injury-related healthcare costs were analyzed.

RESULTS

Of 30,910 patients included, 68.4% were diagnosed with unspecified ankle sprains, 22.8% with concomitant fractures, (6.9%) with isolated lateral sprains, (1.7%) with isolated medial sprains and 0.3% with combined medial/lateral sprains. Pertaining to recurrence, 44.2% had at least one recurrence. Sprains with fractures were ~2-4 times more likely to have surgery within one year following injury (36.2% with fractures; 9.7% with unspecified sprains) and had the highest ankle-related downstream costs.

CONCLUSION

Fractures were a common comorbidity of ankle sprain (one in five injuries), and operative care occurred in 16.4% of cases. Recurrence in this cohort approximates the 40% previously reported in individuals with first-time ankle sprain who progress to chronic ankle instability. Future epidemiological studies should consider reporting on subcategories of ankle sprain injuries to provide a more granular assessment of the distribution of severity.

LEVEL OF EVIDENCE

3b.

Short-Term Effect of Manual Therapy &amp; Taping on Subacute Ankle Sprains with Potential Syndesmotic Sprain: A Case Series

STUDY DESIGN

Case Series.

BACKGROUND

Syndesmotic ankle sprains can occur in up to 17% of ankle trauma and can lead to long-term disability. This study describes the management of seven patients with subacute, high-grade ankle sprains with concerns of concurrent syndesmotic strain utilizing manual therapy and rigid sports taping.

METHODS

Seven active duty military members with clinically diagnosed, high-grade ankle sprains and concern for syndesmotic sprain participated in this case series. All patients received multi-modal treatment consisting of manual therapy, rigid sports taping, progressive exercises, and proprioceptive training. Decrease in Numeric Pain Rating Scale (NPRS) following manual therapy and taping treatment, number of sessions before discharge, and the Global Rating of Change (GROC) at discharge were retrospectively reviewed.

RESULTS

All patients demonstrated an immediate decrease in NPRS following treatment on average of 5 points (range, 3-8 points) with a functional asterisk sign. The improvement in pain and function was maintained until the next treatment session with a mean GROC score of +3. The mean time until recovery was 5.4 weeks (range, 1-8 weeks).

DISCUSSION

A multimodal approach for patients diagnosed clinically with high-grade ankle sprains and concern for syndesmotic sprain was useful to immediately reduce pain and improve function, and improvements were maintained throughout the duration of care. This study is the first to assess a combination of manual therapy and rigid sports taping for the treatment of suspected syndesmotic ankle sprains, and more stringent research is needed to validate the findings.

LEVEL OF EVIDENCE

Therapy, 4.

Serial Within-Session Improvements in Ankle Dorsiflexion During Clinical Interventions Including Mobilization-With-Movement and A Novel Manipulation Intervention - A Case Series

BACKGROUND

Persisting reductions in ankle dorsiflexion range of motion are commonly encountered clinically and seen to be associated with adverse outcomes after ankle and other lower extremity injuries. Accordingly improving identified deficits is a common goal for rehabilitation; however, little data exists documenting any improvement related to interventions in these patients.

PURPOSE

To document the change in dorsiflexion range of motion after stretching and mobilization-with-movement and exercise and a novel manipulation intervention in a population of injured athletes.

DESIGN

Case series in 38 consecutive injured athletes with persisting reductions in ankle dorsiflexion range of motion (42 "stiff" ankles, 34 uninjured) in an outpatient sports physiotherapy clinic.

METHOD

During a single treatment session, two baseline measurements of weight-bearing dorsiflexion were taken at the start of the session to establish reliability and minimum detectable change, and then the same measures were performed after stretching and a mobilization-with-movement intervention, and again after clinical exercise and a novel manipulation which was applied on both ankles.

RESULTS

Excellent reliability was demonstrated (ICC2,1>0.93, MDC=3.5°) for the dorsiflexion measure. Statistically significant (p<0.01), but clinically meaningless improvements were seen after stretching and the mobilization-with-movement intervention on the injured and uninjured legs (1.9° and 1.4° respectively) with greater improvements seen after exercise and the subsequent manipulation (6.9° and 4.7°).

CONCLUSIONS

The relatively simple clinical exercise and manipulation intervention program was associated improvement in dorsiflexion range of motion in this cohort with persisting ankle stiffness. The interventions described largely restored range of motion consistent with baseline levels of the uninjured ankles. Improvements were also seen in the uninjured ankles following intervention.

Preseason weight-bearing ankle dorsiflexion in male professional football players with and without a history of severe ankle injury: A novel analysis in an English Premier League club

OBJECTIVES

Ankle injuries are common in professional football and have profound player/team/club consequences. The weight-bearing lunge-test (WBLT) assesses ankle dorsiflexion range-of-motion in football primary/secondary injury prevention and performance contexts. Data for uninjured and previously ankle-injured players in the English Premier League (EPL) is not available. This study analysed WBLT measurements (cm) within and between uninjured and previously severe ankle-injured players (injured-stiff group, injured-lax group) in one EPL club.

DESIGN

Cross-sectional.

SETTING

Preseason.

PARTICIPANTS

Forty-nine players (age 22.9 ± 4.6 yr; height 181.6 ± 5.2 cm; mass 77.7 ± 7.6 kg).

MAIN OUTCOME MEASURES

Prevalence (%) of previous unilateral severe ankle injury (USAI). Side-to-side (right/left, dominant/nondominant, injured/uninjured) WBLT comparisons at group-level (t-test [within-group]; Welch's ANOVA [between-group]; effect sizes [within-/between-group]) and individual-level (limb symmetry index [%]; absolute-asymmetry [%]).

RESULTS

Prevalence of USAI was 38.7%. There were no statistically-significant side-to-side differences for within-/between-group comparisons. Effect sizes: just-below-large (injured-stiff) and extremely-large (injured-lax) for within-group injured-side/uninjured-side comparisons; just-below-medium (injured-lax) to just-above-medium (injured-stiff) for injured-side comparisons to uninjured players. Absolute-asymmetries: uninjured players, 15.4±13.2%; injured-stiff, 21.8±33.6%; injured-lax 20.4±13.6%.

CONCLUSIONS

Over one-third of players had previous USAI. Effect sizes indicate substantial within-group side-to-side differences and less substantial between-group differences. Across groups, some players had absolute-asymmetries that may elicit concern in ankle primary/secondary injury prevention and performance contexts.