Invertor vs. evertor peak torque and power deficiencies associated with lateral ankle ligament injury

Effect of strength training with additional acupuncture on balance, ankle sensation, and isokinetic muscle strength in chronic ankle instability among college students

Purpose: The effects of the combination of strength training and acupuncture on chronic ankle instability have not been studied. This study examined effects of strength training combined with acupuncture on balance ability, ankle motion perception, and muscle strength in chronic ankle instability among college students. Methods: Forty-six chronic ankle instability college students were randomly categorized into the experimental group (n = 24, strength training + acupuncture) and the control group (n = 22, strength training) for an 8-week intervention. Results: For the results at 8 weeks, compared with the baseline, in the experimental group, the chronic Ankle Instability Tool (CAIT) score, ankle dorsiflexion, plantar flex, eversion peak torque (60°/s), and plantar flex peak torque (180°/s) increased by 13.7%, 39.4%, 13.7%, 14.2%, and 12.3%, respectively. Dorsiflexion, plantar flexion, inversion, and eversion kinesthetic sensation test angles decreased by 17.4%, 20.6%, 15.0%, and 17.2%, respectively. Anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral velocity decreased by 28.9%, 31.6%, 33.3%, and 12.4%, respectively. Anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral mean velocity decreased by 28.9%, 31.6%, 33.3%, and 12.4%, respectively. In the control group, the Cumberland Ankle Instability Tool score and the ankle dorsiflexion peak torque (60°/s) increased by 13.8% and 17.9%, respectively. The inversion kinesthetic sensation test angle decreased by 15.2%, whereas anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral mean velocity decreased by 17.1%, 29.4%, 12.3%, and 16.8%, respectively. 2) For the comparison between the groups after 8 weeks, the values of ankle dorsiflexion and plantar flex peak torque (60°/s) in the experimental group were greater than those in the control group. The values of ankle plantar flex kinesthetic sensation test angle, the anterior-posterior displacement, and anterior-posterior mean velocity in the experimental group were lower than those in the control group. Conclusion: Acupuncture treatment in conjunction with muscle strength training can further improve the balance ability of anterior-posterior, ankle dorsiflexion, and plantar flex strength and plantar flex motion perception in chronic ankle instability participants.

Decreased rate of torque development in ankle evertors for individuals with chronic ankle instability

BACKGROUND

Individuals with chronic ankle instability have decreased peak torque during maximum voluntary contraction in ankle evertors/invertors, and hip abductors. However, it is unclear whether individuals with chronic ankle instability and/or copers demonstrate decreased rate of torque development in ankle evertors/invertors, and hip abductors.

METHODS

54 university-aged participants (18 chronic ankle instability, 18 copers, and 18 controls) performed three maximal isometric contractions for ankle evertors and invertors, and hip abductors. Rate of torque development was defined as the linear slope of the torque-time curve during the first 200 ms of each contraction and compared between the three groups using a one-way analysis of variance (α = 0.05).

FINDINGS

The chronic ankle instability group showed 38.1% less rate of torque development than the coper (P = 0.03 and d = 0.84) and 37.1% than the control groups (P = 0.03 and d = 1.03) in the ankle evertors. For the hip abductors, there were moderate effects between the chronic ankle instability group and the copers (P = 0.06 and d = 0.70), and control groups (P = 0.06 and d = 0.75).

INTERPRETATIONS

The observed between-groups differences in rate of torque development indicate that restoring rate of torque development after lateral ankle sprain may be important to reduce risk of reinjury and development of chronic ankle instability. Clinicians should consider the rate of torque development in the ankle evertors and hip abductors during rehabilitation chronic ankle instability patients.

The effectiveness and sustainability of supervised balance training in chronic ankle instability with grade III ligament injury: a one-year prospective study

Background

To determine the effectiveness and sustainability of supervised balance training in people with chronic ankle instability (CAI) with grade III ligament injury.

Methods

Twenty young adults (12 males and 8 females) diagnosed with CAI with grade III ligament injury underwent 3 months of supervised balance training. The self-reported functional questionnaire, plantar pressure (walking and single leg standing), and isokinetic ankle strength were consecutively evaluated at pre-training, 3 months, 6 months and one year. Paired T tests were used to explore changes in muscle strength and plantar pressures following the supervised balance training. According to whether the patient had sprain recurrence, the patients were divided into sprain recurrence group and control group. The risk factors of sprain recurrence were explored with univariate analysis and multivariable logistic regression.

Results

The self-reported functional scores, the plantar pressure distribution and the muscle strength showed significant immediate improvements after 3 months of supervised balance training. At 6 months post-training, peak force under 2nd metatarsal, time to peak force under the medial hindfoot, time to boundary measurements and dorsiflexion, and eversion strength were partly declined to the pre-training level. 16 patients (80%) resumed the daily life and sports without sprain recurrence during the follow-up. Four patients (20%) reported ankle sprain during the follow-up, and the sprain recurrence group showed significantly higher Beighton scores (p = 0.012) and weaker initial inversion strength (p = 0.022) than the control group.

Conclusions

Three months’ of supervised balance training could effectively improve postural control and muscle strength of CAI cases with grade III ligament injury, although these improvements would partially deceased over time. Additional strength exercises for dorsiflexion and eversion should be supplemented from 6 months. Higher Beighton score and initial inversion muscle strength weakness might increase the risk of sprain recurrence.

Trial registration

ChiCTR, ChiCTR1900023999, Registered 21 June 2019, https://www.chictr.org.cn/edit.aspx?pid=39984&htm=4

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-022-00514-x.

IS VOLAR PLATING IN DISTAL RADIUS FRACTURES SAFE REGARDING PRONATOR QUADRATUS?

ABSTRACT Objective: This study aimed to investigate whether isokinetic strength decrease significantly after using volar plating for distal radius fractures and evaluate the pronator quadratus muscle regarding atrophy. Methods: This study took place between 2011 and 2015 and included 18 distal radius fracture patients (group 1) who were treated via volar plating at least one year prior and 14 healthy controls (group 2). All participants were tested isokinetically. Grip strength, radiological evaluation, wrist range of motion, disabilities of the arm, shoulder, and hand and visual analog scale scores were assessed for clinical and functional outcomes. Ultrasonography evaluated the pronator quadratus muscle thicknesses. Results: The peak supination torque (PT) and supination work per repetition (WPT) strength values significantly decreased (p:0.039, p:0.025, respectively). Although we determined an 11% pronation PT deficit and a 19% pronation WPT deficit, neither were significant. In group 1, the pronator quadratus muscle thickness decreased 5.9% ± 13.3 in the radial area and 9.7% ± 10.5 in the interosseous area according with ultrasonography; these results were not statistically significant compared to group 2. All clinical and functional outcomes were not statistically significant between the groups. Conclusion: The use of volar plating after distal radius fractures is a safe method regarding isokinetic strength and pronator quadratus muscle atrophy. Level of evidence III; Retrospective case-control study .

Electromiographic activity during single leg jump in adolescent athletes with chronic ankle instability: A pilot study

Chronic ankle instability (CAI) is a common condition in athletes, which can alter the muscular activity of lower limb during jump. The objective of the study was to verify the magnitude of activation, onset timing and order of recruitment of the proximal and local muscles to the ankle of young athletes with CAI during a single leg vertical jump. Thirty-seven athletes were selected and divided into: 1) CAI group and 2) control group. An electromyographic evaluation was performed during the jump on force plate. The muscles evaluated were the proximal muscles - gluteus medius (GMed), rectus femoris (RF) and local ankle muscles - tibialis anterior (TA), peroneus longus (PL) and lateral gastrocnemius (LG). In propulsion, the CAI group showed early activation of all evaluated muscles, when compared to control group (p = 0.05). No diferences were found between groups concerning magnitude of electromyographic signal and order of muscle recruitment. During landing, an increase in magnitude of the electromyographic signal of TA in the CAI group was observed and no diferences were found between groups for onset activation and order of muscle recruitment. The results can be applied to athletes' rehabilitation through specific neuromuscular control exercises, such as reaction time and local and proximal joint stabilization to optimize muscle performance and injury incidence. Therefore, in the single leg vertical jump athletes with CAI presented higher activation of the TA in the landing and an early activation of the GMed, RF, TA, PL and LG in propulsion in relation to control group.

Postural Control and Functional Ankle Stability in Professional and Amateur Skateboarders

Basic maneuvers in skateboarding, such as the ollie, put the player at high risk for ankle injuries because of the position of the feet required to perform the maneuvers. This study investigated ankle stability and reaction time for the tibialis anterior, fibularis longus, and fibularis brevis in professional and amateur skateboarders. In total, 16 professional and 16 amateur skateboarders were recruited as participants and underwent range of motion assessments, balance testing, and muscle reaction time measurements. The results revealed that professional skateboarders had a significantly smaller inversion angle compared to amateur players, which suggested better joint control and hence greater safety in the former. Balance testing results indicated better balance in professional skateboarders, and healthy skateboarders had better balance than did injured professional and amateur skateboarders. No significant difference in muscle reaction time was observed between amateur and professional skateboarders.

Hip Abductor Muscle Strength Deficit as a Risk Factor for Inversion Ankle Sprain in Male College Soccer Players: A Prospective Cohort Study

Background:

Previous studies have attempted to determine whether certain risk factors can predict the occurrence of inversion ankle sprains in male collegiate soccer players. However, no consensus has been reached on the predictive risk factors of inversion ankle sprain in this population.

Purpose:

To identify risk factors for inversion ankle sprains among male collegiate soccer players.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

Included were 145 male collegiate soccer players in Japan who were assessed during a preseason medical checkup for potential risk factors of inversion ankle sprain. The preseason assessment included anthropometric measurements, joint laxity and flexibility, muscle flexibility, muscle strength, and balance ability, with a total of 33 variables. The participants were monitored during the 2019 season for inversion ankle sprains as diagnosed by physicians.

Results:

A total of 31 inversion ankle sprains in 31 players (21.4%) occurred during the season. Only the measured isometric hip abductor strength was significantly lower in injured players as compared with uninjured players. Logistic regression analysis revealed measured hip abductor muscle strength deficit as a significant risk factor for inversion ankle sprain (odds ratio, 0.978 [95% CI, 0.976-0.999]; P = .05).

Conclusion:

Hip abductor strength deficit was a risk factor for inversion ankle sprain in the study population. This finding could be useful for the prevention of inversion ankle sprains in male collegiate soccer players.

Does Strength Training for Chronic Ankle Instability Improve Balance and Patient-Reported Outcomes and by Clinically Detectable Amounts? A Systematic Review and Meta-Analysis

OBJECTIVE

Strength training as a form of exercise therapy has long been used to maintain or promote strength, but its effectiveness as a treatment intervention in chronic ankle instability (CAI) is not fully understood. The purpose of this study was to evaluate the effects of strength training compared with no exercise and neuromuscular control training on balance and self-reported function in people with CAI.

METHODS

Eight databases (PubMed, Embase, Cochrane Library, Web of Science, EBSCO, PEDro, CNKI, and WanFang) were searched in June 2020. Randomized controlled trials (RCTs) involving strength training conducted on individuals with CAI were included. Data were extracted by 2 independent reviewers using a standardized form. Methodological quality and risk of bias were assessed by using the PEDro Scale. In addition, the GRADE evaluation system (Grading of Recommendations Assessment, Development and Evaluation) was used to determine the strength of evidence. A total of 554 studies were initially screened, resulting in a final selection of 11 RCTs involving 428 participants, and 8 RCTs were included in the final meta-analysis. Compared with no exercise, strength training demonstrated some benefits in the Star Excursion Balance Test (anterior: weighted mean difference [WMD] = 2.39, 95% CI = 0.60-4.18; posteromedial: WMD = 3.30, 95% CI = 0.24-6.35; posterolateral: WMD = 2.97, 95% CI = 0.37-5.57), but these intervention results did not reach the minimal detectable change values.

CONCLUSION

Available evidence showed that, compared with controls, strength training did not produce any minimal detectable changes on Star Excursion Balance Test or Foot and Ankle Ability Measure scores in individuals with CAI. Clinicians should use strength training cautiously for improving balance and symptoms in CAI.

IMPACT

The results of this study may have an impact on selecting effective physical therapy interventions for managing symptoms associated with CAI.

EFFECTS OF WEARING AN ANKLE BRACE ON GROUND REACTION FORCES DURING JUMPS IN BASKETBALL GAME SIMULATION

ABSTRACT Introduction: The use of ankle braces reduces the risk of ankle injuries in basketball players. However, the mechanisms of injury protection provided by the ankle braces in the basketball game are still unknown. Objectives: To analyze the effects of wearing a lace-up ankle brace, and to conduct an exercise protocol that simulated the intensity of the basketball game on ground reaction force (GRF) during basketball-specific vertical jumps. Methods: Eleven male younger basketball players aged under 18 completed 48 vertical jumps, with and without ankle braces, during an exercise protocol composed of four 10-minute periods, simulating the activity profile and intensity of the basketball game as well as the typical intervals between periods. Mediolateral (variables: the greatest medial and lateral peaks) and vertical (variables: vertical peak, impulse peak, impulse at 50 ms of landing, loading rate and jump height) GRF were measured during takeoff and landing for all the jumps performed in the exercise protocol. Results: The use of the ankle brace reduced mediolateral GRF in all periods of the exercise protocol during takeoff and landing ( P < 0.05), without affecting the vertical GRF ( P > 0.05). Mediolateral and vertical GRF (takeoff mediolateral vertical peaks, landing mediolateral peaks, landing impulse peak, takeoff and landing loading rate) increased significantly during four subsequent 10-minute periods ( P < 0.05). However, for mediolateral GRF, the increase overtime was higher without braces. Conclusions: The use of the ankle brace reduced the mediolateral GRF on the lower limb, while there was a progressive increase in the external load applied to the body during the vertical jumps in the subsequent periods of the exercise protocol performed at the same intensity of the basketball game. Level of evidence I; Randomized clinical trial .

Effects of Whole-Body Vibration and Balance Training on Female Athletes with Chronic Ankle Instability

We explored the effects of 6-week whole-body vibration (WBV) and balance training programs on female athletes with chronic ankle instability (CAI). This randomized controlled study involved female athletes with dominant-leg CAI. The participants were randomly divided into three groups: WBV training (Group A), balance training (Group B), and nontraining (control group; Group C). Groups A and B performed three exercise movements (double-leg stance, one-legged stance, and tandem stance) in 6-week training programs by using a vibration platform and balance ball, respectively. The Star Excursion Balance Test (SEBT), a joint position sense test, and an isokinetic strength test were conducted. In total, 63 female athletes with dominant-leg CAI were divided into three study groups (all n = 21). All of them completed the study. We observed time-by-group interactions in the SEBT (p = 0.001) and isokinetic strength test at 30°/s of concentric contraction (CON) of ankle inversion (p = 0.04). Compared with the control group, participants of the two exercise training programs improved in dynamic balance, active repositioning, and 30°/s of CON and eccentric contraction of the ankle invertor in the SEBT, joint position sense test, and isokinetic strength test, respectively. Furthermore, the effect sizes for the assessed outcomes in Groups A and B ranged from very small to small. Female athletes who participated in 6-week training programs incorporating a vibration platform or balance ball exhibited very small or small effect sizes for CAI in the SEBT, joint position sense test, and isokinetic strength test. No differences were observed in the variables between the two exercise training programs.

Submaximal Force Steadiness and Accuracy in Patients With Chronic Ankle Instability

CONTEXT

Patients with chronic ankle instability (CAI) have demonstrated sensorimotor impairments. Submaximal force steadiness and accuracy measure sensory, motor, and visual function via a feedback mechanism, which helps researchers and clinicians comprehend the sensorimotor deficits associated with CAI.

OBJECTIVE

To determine if participants with CAI experienced deficits in hip and ankle submaximal force steadiness and accuracy compared with healthy control participants.

DESIGN

Case-control study.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Twenty-one patients with CAI and 21 uninjured individuals.

MAIN OUTCOME MEASURE(S)

Maximal voluntary isometric contraction (MVIC) and force steadiness and accuracy (10% and 30% of MVIC) of the ankle evertors and invertors and hip abductors were assessed using the central 10 seconds (20%-87% of the total time) of the 3 trials.

RESULTS

Relative to the control group, the CAI group demonstrated less accuracy of the invertors (P < .001). Across all motions, the CAI group showed less steadiness (P < .001) and less accuracy (P < .01) than the control group at 10% of MVIC. For MVIC, the CAI group displayed less force output in hip abduction than the uninjured group (P < .0001).

CONCLUSIONS

Patients with CAI were unable to control ongoing fine force (10% and 30% of MVIC) through a feedback mechanism during an active test. These findings suggested that deficits in sensorimotor control predisposed patients with CAI to injury positions because they had difficulty integrating the peripheral information and correcting their movements in relation to visual information.

Effects of proprioceptive training on ankle muscle strength in fencers: A clinical trial

BACKGROUND

Fencing is a combat sport, which depends of lower limbs muscular strength and neuromuscular function. Because of that, approximately half of all injuries occur in lower limbs, especially in ankle. Thus, the objective of this study was to verify the influence of a twelve-week proprioceptive training program on ankle muscular strength and muscular balance in fencers.

METHODS

The study was a clinical trial, with 19 fencing athletes from 14 to 35-year-old. The main outcome was ankle invertors, evertors, plantiflexors and dorsiflexors muscular strength and ankle muscle balance. The study was performed in six stages: familiarization of muscular strength test in isokinetic dynamometer; pre-intervention; intervention; post-intervention; three- and six-months follow-up. At pre-intervention stage, the muscular strength was evaluated. At intervention stage, the athletes performed 12-week proprioceptive training program, three times a week. At post-intervention, three- and the six-months follow-ups, same pre-intervention test was performed.

RESULTS

The proprioceptive training improved front leg ankle dorsiflexor strength at three- and six-months follow-ups compared to pre-intervention. Furthermore, training increased the front leg dorsiflexors/plantiflexors conventional ratio at three- and six-months follow-ups compared to pre-intervention; and evertors/invertors conventional ratio at three-months follow-up compared to pre-intervention; and evertors/invertors functional ratio at post-intervention and three- and six-months follow-ups compared to pre-intervention.

CONCLUSIONS

The improvement and/or maintenance of ankle muscle strength occurred in intervention group seems to be due to stimulus provided by proprioceptive training, with ankle dorsiflexors being the most stimulated group.

Effects of lateral ankle sprain on range of motion, strength and postural balance in competitive basketball players: a cross-sectional study

BACKGROUND

Lateral ankle sprain is the most common injury in basketball, and many of these sprains resulted in residual functional deficits. This study aimed to compare ankle strength and range of motion, and postural balance between competitive basketball players with and without lateral ankle sprain.

METHODS

This was a cross-sectional study involving 42 male competitive basketball players. Subjects were divided into the injured and uninjured groups based on self-reported questionnaires. Ankle range of motion (ROM) was measured using a goniometer, ankle isokinetic strength testing performed using Biodex System 4 PRO, and single-leg stability tests performed using Biodex Balance System SD.

RESULTS

Between the injured and uninjured ankles, there was a decrease in plantarflexion ROM (44.89±6.85 vs. 50.75±9.31, P<0.05) and an increase in eversion ROM (14.50±5.63 vs. 11.74±4.53, P<0.05). There was a reduction in inversion and plantarflexion strength at 30°/s peak torque and 120 °/s peak torque (P<0.05). However, no significant difference observed in the postural stability indexes between the two groups.

CONCLUSIONS

This study proves that there are residual ROM and strength deficits after an ankle sprain, however, these deficits do not affect their balance ability.

Ankle strength is not strongly associated with postural stability in patients awaiting surgery for chronic lateral ankle instability

PURPOSE

(1) To describe ankle strength and postural stability in patients with chronic lateral ankle instability and (2) to analyse the correlation between deficits in ankle strength and postural stability.

METHODS

Results of preoperative isokinetic and balance tests in 203 patients whose contralateral ankle was normal were retrospectively reviewed. Isokinetic peak torque values of eversion and inversion at 2 angular velocities (30°/s and 120°/s) were measured in the injured and normal ankles. In the balance test, the percent differences of 3 actual scores (overall, anterior-posterior, and medial-lateral) between the injured and normal ankles were calculated. Additional statistical analyses were performed to evaluate weakness of ankle strength, postural stability deficits, and their correlation.

RESULTS

Significant differences in 4 peak torque values and 4 relative peak torque values (peak torque/body weight) were found between the injured and normal ankles. All 8 values were significantly lower in the injured ankles. Weakness was severe during inversion and at 30°/s. In the balance test, 49 subjects (24.1%) had significant deficits in postural stability and 109 (53.7%) had favourable results. No strong association was found between weakness of ankle strength and deficits in postural stability.

CONCLUSIONS

Strength measurement alone is insufficient to evaluate preoperative functional deficits, and other functional tests are required to measure postural stability. The results of this study provide further evidence for a rehabilitation programme consisting of proprioceptive training as well as strengthening. The proprioceptive training must be an integral part of the rehabilitation programme in addition to strengthening exercise.

LEVEL OF EVIDENCE

Case series, Level IV.

Relationship Between Isokinetic Muscle Strength and Functional Tests in Chronic Ankle Instability

Isokinetic muscle strength measurements and functional tests are usually performed to evaluate ankle condition in chronic ankle instability (CAI), yet there is no clear demonstration of the relationship between isokinetic muscle strength and functional tests. The objective of this study was to evaluate the relationship between isokinetic muscle strength and functional tests in CAI. Between April 2014 and August 2016, 103 patients with unilateral CAI were studied. Single-leg balance, single-heel raise, and single-leg squat tests were performed for static balancing assessment. Single-leg hop, double-leg jump, and sidestep tests were performed for dynamic balancing assessment. The isokinetic muscle strength of both ankles was measured using a dynamometer. The involved ankle showed lower muscle strength in inversion than the uninvolved ankle, while eversion, dorsiflexion, and plantarflexion muscle strength had no significant differences between ankles. There were significant correlations between the isokinetic muscle strength of inversion and the single-leg balance test, single-heel raise test, and sidestep test (Pearson's r; 0.246, 0.514, and 0.229 at 30°/second; 0.288, 0.473, and 0.239 at 180°/second, respectively). The single leg balance, single heel raise, and sidestep tests are useful to assess not only ankle functional performance but also isokinetic muscle strength. Among these tests, the single heel raise test was the most reliable test to reflect muscle strength deficiency in CAI.

Ability of Functional Performance Tests to Identify Individuals With Chronic Ankle Instability: A Systematic Review With Meta-Analysis

OBJECTIVE

The purpose of this systematic review with meta-analysis was to determine the effectiveness of functional performance tests (FPTs) in differentiating between individuals with chronic ankle instability (CAI) and healthy controls.

DATA SOURCES

The National Library of Medicine Catalog (PubMed), the Cumulative Index for Nursing and Allied Health Literature (CINAHL), and the SPORTDiscus, from inception to June 2017 were searched. Search terms consisted of: "Functional Performance Test*" OR "Dynamic Balance Test*" OR "Postural Stability Test*" OR "Star Excursion Balance Test*" OR "Hop Test*" AND "Ankle Instability" OR "Ankle Sprain." Included articles assessed differences in FPTs in patients with CAI compared with a control group.

MAIN RESULTS

Included studies were assessed for methodological quality and level of evidence. Individual and mean effect sizes were also calculated for FPTs from the included articles. Twenty-nine studies met the criteria and were analyzed. The most common FPTs were timed-hop tests, side-hop, multiple-hop test, single-hop for distance, foot-lift test, and the Star Excursion Balance Tests (SEBTs). The side-hop (g = -1.056, P = 0.009, n = 7), timed-hop tests (g = -0.958, P = 0.002, n = 9), multiple-hop test (g = 1.399, P < 0.001, n = 3), and foot-lift tests (g = -0.761, P = 0.020, n = 3) demonstrated the best utility with large mean effect sizes, whereas the SEBT anteromedial (g = 0.326, P = 0.022, n = 7), medial (g = 0.369, P = 0.006, n = 7), and posteromedial (g = 0.374, P < 0.001, n = 13) directions had moderate effects.

CONCLUSIONS

The side-hop, timed-hopping, multiple-hop, and foot-lift seem the best FPTs to evaluate individuals with CAI. There was a large degree of heterogeneity and inconsistent reporting, potentially limiting the clinical implementation of these FPTs. These tests are cheap, effective, alternatives compared with instrumented measures.

Plausible mechanisms of and techniques to assess ankle joint degeneration following lateral ankle sprains: a narrative review

Lateral ankle sprain (LAS) is the most common lower extremity musculoskeletal injury sustained during daily life and sport. The cascade of events that starts with ligamentous trauma leads to clinical manifestations such as recurrent sprains and giving way episodes, hallmark characteristics of chronic ankle instability (CAI). The sequelae of lateral ankle sprains and CAI appear to contribute to aberrant biomechanics. Combined, joint trauma and aberrant biomechanics appear to directly and/or indirectly play a role in talar cartilage degeneration. Up to 80% of all cases of ankle osteoarthritis (OA) are post-traumatic in nature and common etiologies for ankle post-traumatic osteoarthritis (PTOA) are histories of a single and recurrent ankle sprains. Despite known links between LAS, CAI, and PTOA and evidence demonstrating the burden of LAS and its sequelae, early pathoetiological changes of ankle PTOA and how they can be assessed are poorly understood. Therefore, the purpose of this paper is to review the plausible mechanistic links among LAS and its sequelae of CAI and PTOA as well as review non-surgical techniques that can quantify talar cartilage health. Understanding the pathway from ligamentous ankle injury to ankle PTOA is vital to developing theoretically sound therapeutic interventions aimed at slowing ankle PTOA progression. Further, directly assessing talar cartilage health non-surgically provides opportunities to quantify if current and novel intervention strategies are able to slow the progression of ankle PTOA.

An Updated Model of Chronic Ankle Instability

Lateral ankle sprains (LASs) are among the most common injuries incurred during participation in sport and physical activity, and it is estimated that up to 40% of individuals who experience a first-time LAS will develop chronic ankle instability (CAI). Chronic ankle instability is characterized by a patient's being more than 12 months removed from the initial LAS and exhibiting a propensity for recurrent ankle sprains, frequent episodes or perceptions of the ankle giving way, and persistent symptoms such as pain, swelling, limited motion, weakness, and diminished self-reported function. We present an updated model of CAI that aims to synthesize the current understanding of its causes and serves as a framework for the clinical assessment and rehabilitation of patients with LASs or CAI. Our goal was to describe how primary injury to the lateral ankle ligaments from an acute LAS may lead to a collection of interrelated pathomechanical, sensory-perceptual, and motor-behavioral impairments that influence a patient's clinical outcome. With an underpinning of the biopsychosocial model, the concepts of self-organization and perception-action cycles derived from dynamic systems theory and a patient-specific neurosignature, stemming from the Melzack neuromatrix of pain theory, are used to describe these interrelationships.

Bilateral Strength Asymmetries and Unilateral Strength Imbalance: Predicting Ankle Injury When Considered With Higher Body Mass in US Special Forcesa

CONTEXT

Ankle injury is one of the most common conditions in athletics and military activities. Strength asymmetry (SA) and imbalance may represent a risk factor for injury, but past investigations have produced ambiguous conclusions. Perhaps one explanation for this ambiguity is the fact that these authors used univariate models to predict injury.

OBJECTIVE

To evaluate the predictive utility of SA and imbalance calculations for ankle injury in univariate and multivariate prediction models.

DESIGN

Prospective cohort study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 140 male US Air Force Special Forces.

MAIN OUTCOME MEASURE(S)

Baseline testing consisted of body composition, isometric strength, and aerobic and anaerobic capacity. A clinician conducted medical chart reviews 365 days posttesting to document the incidence of ankle injury. Strength asymmetries were calculated based on the equations most prevalent in the literature along with known physiological predictors of injury in the military: age, height, weight, body composition, and aerobic capacity. Simple logistic regression was conducted using each predictor, and backward stepwise logistic regression was conducted with each equation method and the physiological predictors entered initially into the model.

RESULTS

Strength asymmetry or imbalance or both, as a univariate predictor, was not able to predict ankle injury 365 days posttesting. Body mass (P = .01) and body mass index (P = .01) significantly predicted ankle injury. Strength asymmetry or imbalance or both significantly predicted ankle injury when considered with body mass (P = .002-.008).

CONCLUSIONS

As a univariate predictor, SA did not predict ankle injury. However, SA contributed significantly to predicting ankle injury in a multivariate model using body mass. Interpreting SA and imbalance in the presence of other physiological variables can help elucidate the risk of ankle injury.

The peroneal strength deficits in patients with chronic ankle instability compared to ankle sprain copers and normal individuals

BACKGROUND

Despite a consensus regarding the correlation of peroneal strength deficit with chronic ankle instability (CAI), there are conflicting reports in regards to peroneal strength as assessed by isokinetic dynamometer in patients with CAI. The purpose of this study was to evaluate the changes of isokinetic strength in patients with CAI compared to ankle sprain copers and normal individuals.

METHODS

Forty-two patients (CAI group) with chronic ankle instability who were scheduled for the modified Broström procedure met inclusion criteria. Thirty-one ankle sprain copers (ASC group) who were eligible at 6 months after acute injury and 30 controls were recruited. The muscle strength associated with four motions of the ankle were evaluated using isokinetic dynamometer.

RESULTS

Peak torque for inversion and eversion at 60°/s angular velocity were significantly lower in the CAI group compared to the ASC and control group (P=.004, P<.001, respectively). Deficit ratio of peak torque for eversion at 60°/s and 120°/s in the CAI group were 33.8% and 19.8%, respectively, which indicated significant side to side differences (both P<.001). The evertor/invertor strength ratio (0.59) for eversion at 60°/s was significantly lower in the CAI group (P<.001).

CONCLUSION

As compared to the ankle sprain copers and normal individuals, patients with chronic ankle instability who were scheduled for modified Broström procedure demonstrated a significant weakness of isokinetic peroneal strength. Isokinetic muscular assessment can provide the useful preoperative informations regarding functional ankle instability focusing on peroneal weakness.

Does the cleat model interfere with ankle sprain risk factors in artificial grass?

BACKGROUND

The cleats-surface interaction has been described as a possible risk factor for lateral ankle sprain. However, their interaction is still unknown in individuals with chronic ankle instability. The purpose of this study was to determine the influence of different soccer cleats on kinematic, kinetic and neuromuscular ankle variables on artificial grass in soccer players with and without chronic ankle instability.

METHODS

Eighty-two amateur athletes divided in two groups: 40 with chronic ankle instability and 42 without chronic ankle instability. All subjects performed 2 series of 6 consecutive crossover jumps with dominant foot, each one with one of the four models of cleats (Turf, Artificial grass, Hard and Firm ground). Cleat and group main effect and interactions of kinematic, kinetic and neuromuscular variables were analyzed according to factorial repeated measures ANOVA.

FINDINGS

No statistically significant cleat and group main effect and interactions were identified in kinematic, kinetic and electromyographic magnitude of the peroneal muscles. A main effect of the group was observed for peroneus longus activation time for TF model (p = 0.010).

INTERPRETATION

In soccer players, the contributor variables for ankle sprain were not influenced by the kind of soccer cleat used in a functional jump test on artificial grass. However, players with chronic ankle instability present delayed postural adjustments in peroneus longus with the TF model compared to players without chronic ankle instability.

Mild-to-Moderate Hallux Valgus Does Not Decrease Ankle Muscle Strength in Middle-Aged Japanese Women: A Comparative Study

Extreme hallux valgus has been documented to be related to lower functional ability and health-related quality of life. It also has a negative effect on foot structure and biomechanical characteristics, which in turn may affect muscle strength in the foot and ankle. Thus, the purposes of this study were to determine whether there is a difference of ankle muscle strength in varied hallux valgus deformities and to investigate correlations between hallux valgus angles and ankle muscle strength. Hallux valgus angles and ankle muscle strength data were collected from 31 middle-aged Japanese women. The hallux valgus angle was measured with a 3-dimensional foot scanner; ankle muscle strength was measured with a dynamometer. Results showed no differences in ankle muscle strength between normal and mild-to-moderate hallux valgus at both 60º/second and 120º/second (p > .05). Unexpectedly, women with mild-to-moderate hallux valgus had a greater value for inversion peak torque per body weight and eversion-to-inversion ratio than those with normal hallux valgus (p = .019 and p = .022) at 120º/second. Furthermore, hallux valgus was correlated with inversion peak torque and peak torque per body weight (r = 0.47; p = .012 and r = 0.50; p = .007) and associated with eversion-to-inversion strength ratio (r = -0.47; p = .012). The findings indicated that mild-to-moderate hallux valgus did not result in a decrease in ankle muscle strength. Conversely, mild-to-moderate hallux valgus had greater ankle inversion strength in middle-aged Japanese women. Further studies are needed to investigate ankle muscle strength in severe hallux valgus deformities.

Effects of the standard physiotherapy programme on pain and isokinetic ankle strength in individuals with grade I ankle sprain

Objectives

The isokinetic evaluation of the ankle joint is important in determining the effectiveness of the rehabilitation programme for the management of ankle sprains. This study aimed to determine the effects of physiotherapy programme on isokinetic variables in individuals with grade I ankle sprains.

Methods

Seven patients with acute grade 1 ankle sprain (15 days of ankle sprain) were recruited. They were provided with 7 days of protection, optimal loading, ice, compression, and elevation (POLICE) treatment, and the standard physiotherapy programme consisted of towel stretching and balancing exercises on one leg. Pain scale score was recorded daily during the physiotherapy programme. The isokinetic ankle strengths of the patient's injured and uninjured legs were compared before and after the physiotherapy programme. Isokinetic tests were conducted in painless range of motion for the injured leg.

Results

Pain was significantly reduced after the patients underwent the standard physiotherapy programme. No significant differences were observed in terms of the ankle peak torque, time to peak torque, and ankle plantar flexion-to-dorsiflexion ratio of the injured and uninjured legs. The injured leg showed significant improvement in terms of ankle eversion-to-inversion ratio (E:I) after 7 days of performing the standard physiotherapy programme.

Conclusion

Performing the standard physiotherapy programme for 1 week reduces pain and improves the ankle E:I in patients with grade 1 ankle sprain.

Bilateral compensatory postural adjustments to a unilateral perturbation in subjects with chronic ankle instability

BACKGROUND

To evaluate the magnitude of bilateral compensatory postural adjustments in response to a unilateral sudden inversion perturbation in subjects with chronic ankle instability.

METHODS

24 athletes with chronic ankle instability (14 with functional ankle instability, 10 with mechanical ankle instability) and twenty controls participated in this study. The bilateral electromyography of ankle muscles was collected during a unilateral sudden ankle inversion to assess the magnitude of subcortical and voluntary compensatory postural adjustments in both the perturbed and the contralateral limb (support limb).

FINDINGS

In the support position, compared to the control group, the group with functional ankle instability presented decreased compensatory postural adjustments of the tibialis anterior in both the injured and the uninjured limbs in the support position and of the soleus in the uninjured limb. In the side of the perturbation, participants with functional ankle instability presented decreased soleus compensatory postural adjustments in the uninjured limb when compared to the control group. Increased values of soleus and peroneal brevis compensatory postural adjustments were observed in the group with mechanical instability when compared to the control group and to the group with functional ankle instability.

INTERPRETATION

Subjects with functional ankle instability present bilateral impairment of compensatory postural adjustments of the tibialis anterior in a support position and of the soleus of the uninjured limb regardless of the position. Subjects with mechanical instability present bilateral increase of these adjustments in the peroneal brevis regardless of the position and in the soleus muscle in the side of the perturbation.

Diagnosis, treatment and prevention of ankle sprains: update of an evidence-based clinical guideline

This guideline aimed to advance current understandings regarding the diagnosis, prevention and therapeutic interventions for ankle sprains by updating the existing guideline and incorporate new research. A secondary objective was to provide an update related to the cost-effectiveness of diagnostic procedures, therapeutic interventions and prevention strategies. It was posited that subsequent interaction of clinicians with this guideline could help reduce health impairments and patient burden associated with this prevalent musculoskeletal injury. The previous guideline provided evidence that the severity of ligament damage can be assessed most reliably by delayed physical examination (4-5 days post trauma). After correct diagnosis, it can be stated that even though a short time of immobilisation may be helpful in relieving pain and swelling, the patient with an acute lateral ankle ligament rupture benefits most from use of tape or a brace in combination with an exercise programme.New in this update: Participation in certain sports is associated with a heightened risk of sustaining a lateral ankle sprain. Care should be taken with non-steroidal anti-inflammatory drugs (NSAIDs) usage after an ankle sprain. They may be used to reduce pain and swelling, but usage is not without complications and NSAIDs may suppress the natural healing process. Concerning treatment, supervised exercise-based programmes preferred over passive modalities as it stimulates the recovery of functional joint stability. Surgery should be reserved for cases that do not respond to thorough and comprehensive exercise-based treatment. For the prevention of recurrent lateral ankle sprains, ankle braces should be considered as an efficacious option.

Acute lateral ankle sprain to chronic ankle instability: a pathway of dysfunction

Lateral ankle sprains (LAS) have been reported as one of the most common musculoskeletal injuries observed in sports and in individuals who are recreationally active. Approximately 40% of individuals who sustain a LAS develop a condition known as chronic ankle instability (CAI). Years of research has identified numerous impairments associated with CAI such as decreases in range of motion (ROM), strength, postural control, and altered movement patterns during functional activities when compared to individuals with no LAS history. As a result, an impairment-based rehabilitation model was developed to treat the common impairments associated with CAI. The impairment-based rehabilitation model has been shown to be an effective rehabilitation strategy at improving both clinical and patient-oriented outcomes in patients with CAI. To date, the efficacy of an impairment-based rehabilitation model has not been evaluated in patients with an acute LAS. Prior to implementing an impairment-based model for the treatment of an acute LAS, similarities between impairments associated with acute LAS and CAI across the spectrum of the healing process is warranted. Therefore, the purpose of this review paper is to compare and contrast impairments and treatment techniques in individuals with an acute LAS, sub-acute LAS, and CAI. A secondary purpose of this review is to provide clinical commentary on the management of acute LAS and speculate how the implementation of an impairment-based rehabilitation strategy for the treatment of acute LAS could minimize the development of CAI. The main findings of this review were that similar impairments (decreased ROM, strength, postural control, and functional activities) are observed in patients with acute LAS, sub-acute LAS, and CAI, suggesting that the impairments associated with CAI are a continuation from the original impairments developed during the initial LAS. Therefore, the use of an impairment-based model may be advantageous when treating patients with an acute LAS.

The Effect of Peroneal Muscle Strength on Functional Outcomes After the Modified Broström Procedure for Chronic Ankle Instability

BACKGROUND

Although the peroneal muscles are known to be the major dynamic lateral stabilizers of the ankle, little information is available regarding the change in muscle strength and relation with the outcomes after lateral ligament repair surgery. The purpose of this study was to identify the effects of peroneal strength on the validated functional outcome measures after the modified Broström procedure (MBP) for chronic ankle instability.

METHODS

Forty-one patients (41 ankles) who underwent MBP using suture anchors were eligible and followed up to 2 years postoperatively. Functional evaluation consisted of the Foot and Ankle Outcome Score (FAOS), and Foot and Ankle Ability Measure (FAAM). The changes of peroneal strength were evaluated using an isokinetic dynamometer. Differences in the functional outcomes between the 3 groups divided according to the recovery rate of peroneal strength were analyzed.

RESULTS

Peak torque and total work for eversion in 60 degrees/s angular velocity significantly improved from a mean 8.1 and 5.2 Nm preoperatively to 11.4 and 6.9 Nm at postoperative 2 years, respectively ( P < .001, P = .038). The deficit ratio of peak torque for eversion significantly improved from a mean 38.6% to 17.4%, and a significant side-to-side difference was found ( P = .011). There were no significant differences in FAOS, FAAM, and measurements of stress radiograph between the 3 groups.

CONCLUSIONS

Although restoration of peroneal strength postoperatively was about 82.6% of the unaffected ankle, patient-reported function in daily and sport activities were satisfactorily improved. Postoperative isokinetic strength of the peroneals demonstrated no statistically significant effects on the functional outcomes after MBP.

LEVEL OF EVIDENCE

Level III, prospective comparative case series.

Immediate effects of shoes inducing ankle-destabilization around Henke's axis during challenging walking gaits: Gait kinematics and peroneal muscles activities

Due to its high frequency of occurrence, as well as possible residual symptoms, proper treatment of lateral ankle sprains (LAS) is important. From a physiological point of view, increasing the quantity of electromyographic (EMG) activity in the peroneal muscles will mechanically improve the functional stability of the ankle joint. The present study investigated the immediate effects of an ankle destabilization device (ADD) specifically designed to induce imbalances along the Henke's axis during 3 challenging walking tasks. As the effects of such a device have to be tested on healthy participants before being implemented in rehabilitation programs, 12 healthy participants performed 3 different types of walking (normal, aligned, and jumping walking) while the EMG activities in four peroneal muscles and the main gait kinematics parameters were recorded. Our results clearly demonstrated that wearing the ADD during these different walking tasks significantly increased EMG activities in the four peroneal muscles (increases from 9 to 33% on average depending on the muscle and the walking condition) while maintaining previous gait kinematic patterns. Our study shows that an ADD coupled with walking or jumping tasks is able to improve neuromuscular activity. It should therefore be useful for ankle rehabilitation therapy and the prevention of LAS.

Acute ankle sprain: conservative or surgical approach?

Ankle sprains fall into two main categories: acute ankle sprains and chronic ankle instability, which are among the most common recurrent injuries during occupational activities, athletic events, training and army service.

Acute ankle sprain is usually managed conservatively and functional rehabilitation failure by conservative treatment leads to development of chronic ankle instability, which most often requires surgical intervention.

Enhancing the in-depth knowledge of the ankle anatomy, biomechanics and pathology helps greatly in deciding the management options.

Cite this article: Al-Mohrej OA, Al-Kenani NS. Acute ankle sprain: conservative or surgical approach? EFORT Open Rev 2016;1:34-44. DOI: 10.1302/2058-5241.1.000010.

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.

Using Ankle Bracing and Taping to Decrease Range of Motion and Velocity During Inversion Perturbation While Walking

CONTEXT

Prophylactic ankle supports are commonly used. However, the effectiveness of external supports in preventing an inversion stress has been debated.

OBJECTIVE

To evaluate how ankle bracing and taping affect inversion range of motion, time to maximum inversion, inversion velocity, and perceived ankle stability compared with a control condition during a dynamic inversion perturbation while walking.

DESIGN

Crossover study.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 42 physically active participants (16 men, 26 women; age = 21.2 ± 3.3 years, height = 168.9 ± 8.9 cm, mass = 66.1 ± 11.4 kg) volunteered.

INTERVENTION(S)

Participants walked on a custom-built walkway that suddenly inverted their ankles to 30° in 3 conditions: brace, tape, and control (no external support). We used an ASO ankle brace for the brace condition and a closed basketweave technique for the tape condition. Three trials were completed for each condition. Main Outcome Measure(s) Maximum inversion (degrees), time to maximum inversion (milliseconds), and inversion velocity (degrees per second) were measured using an electrogoniometer, and perceived stability (centimeters) was measured using a visual analog scale.

RESULTS

Maximum inversion decreased more in the brace condition (20.1°) than in the control (25.3°) or tape (22.3°) conditions (both P values = .001), and the tape condition restricted inversion more than the control condition (P = .001). Time to maximum inversion was greater in the brace condition (143.5 milliseconds) than in the control (123.7 milliseconds; P = .001) or tape (130.7 milliseconds; P = .009) conditions and greater in the tape than in the control condition (P = .02). Inversion velocity was slower in the brace condition (142.6°/s) than in the control (209.1°/s) or tape (174.3°/s) conditions (both P values = .001) and slower in the tape than in the control condition (P = .001). Both the brace and tape conditions provided more perceived stability (0.98 cm and 0.94 cm, respectively) than the control condition (2.38 cm; both P values = .001).

CONCLUSIONS

Both prophylactic conditions affected inversion range of motion, time to maximum inversion, inversion velocity, and perceived ankle stability. However, bracing provided more restriction at a slower rate than taping.

Using Balance Tests to Discriminate Between Participants With a Recent Index Lateral Ankle Sprain and Healthy Control Participants: A Cross-Sectional Study

CONTEXT

The first step to identifying factors that increase the risk of recurrent ankle sprains is to identify impairments after a first sprain and compare performance with individuals who have never sustained a sprain. Few researchers have restricted recruitment to a homogeneous group of patients with first sprains, thereby introducing the potential for confounding.

OBJECTIVE

To identify impairments that differ in participants with a recent index lateral ankle sprain versus participants with no history of ankle sprain.

DESIGN

Cross-sectional study.

PATIENTS OR OTHER PARTICIPANTS

We recruited a sample of convenience from May 2010 to April 2013 that included 70 volunteers (age = 27.4 ± 8.3 years, height = 168.7 ± 9.5 cm, mass = 65.0 ± 12.5 kg) serving as controls and 30 volunteers (age = 31.1 ± 13.3 years, height = 168.3 ± 9.1 cm, mass = 67.3 ± 13.7 kg) with index ankle sprains.

MAIN OUTCOME MEASURE(S)

We collected demographic and physical performance variables, including ankle-joint range of motion, balance (time to balance after perturbation, Star Excursion Balance Test, foot lifts during single-legged stance, demi-pointe balance test), proprioception, motor planning, inversion-eversion peak power, and timed stair tests. Discriminant analysis was conducted to determine the relationship between explanatory variables and sprain status. Sequential discriminant analysis was performed to identify the most relevant variables that explained the greatest variance.

RESULTS

The average time since the sprain was 3.5 ± 1.5 months. The model, including all variables, correctly predicted a sprain status of 77% (n = 23) of the sprain group and 80% (n = 56) of the control group and explained 40% of the variance between groups ([Formula: see text] = 42.16, P = .03). Backward stepwise discriminant analysis revealed associations between sprain status and only 2 tests: Star Excursion Balance Test in the anterior direction and foot lifts during single-legged stance ([Formula: see text] = 15.2, P = .001). These 2 tests explained 15% of the between-groups variance and correctly predicted group membership of 63% (n = 19) of the sprain group and 69% (n = 48) of the control group.

CONCLUSIONS

Balance impairments were associated with a recent first ankle sprain, but proprioception, motor control, power, and function were not.

Postural control systems in two different functional movements: a comparison of subjects with and without chronic ankle instability

[Purpose] The aim of this study was to evaluate postural control during two different movements of the Functional Movement Screen in patients with chronic ankle instability compared with healthy subjects. [Subjects] This study was a cross-sectional survey of 50 participants comprised of 25 chronic ankle instability patients and 25 healthy subjects. [Methods] All subjects were subjected to measurement of the Foot and Ankle Disability Index and center of pressure and Functional Movement Screen testing. The deep squat and hurdle step were performed for the lower extremities in Functional Movement Screen testing. Then, the center of pressure was measured with balance assessment software using a Nintendo Wii Balance Board. The center of pressure path length, velocity, and area of the 95% confidence ellipse and Functional Movement Screen scores were evaluated for all subjects. [Results] The results showed significant differences in center of pressure path length, velocity, and area of the 95% confidence ellipse between the groups for the hurdle step with the non-affected limb. However, there were no significant differences between groups for the deep squat and hurdle step with the affected limb. [Conclusion] The results of this study showed that there was a difference in the hurdle step with the non-affected limb in chronic ankle instability patients compared with normal subjects.

Angle-torque relationship of the subtalar pronators and supinators in younger and elderly males and females

BACKGROUND

The angle-dependent torque capacity of the subtalar pronators and supinators is important to maintain dynamic ankle stabilisation. Based on the peak torques during maximum voluntary isometric pronation and supination across the subtalar range of motion, the strength curves of younger and elderly males and females were investigated.

METHODS

Maximum voluntary isometric subtalar pronator and supinator strength tests were administered to 30 younger and 30 elderly volunteers (each 15 male and 15 female subjects). Total active subtalar range of motion and peak pronator and supinator torques were measured in five anatomical subtalar joint angles using a custom-built apparatus with two force transducers. Furthermore, relative torques (normalised to the individual peak torque) and pronator-to-supinator strength-ratios were also calculated.

RESULTS

Pronator-to-supinator strength ratio, and peak pronator and supinator torques are affected by age and by joint angle x age interactions. All supinator strength curves show a steadily descending characteristic from the pronated to the supinated positions. The pronator strength curve had an inverted U-shaped characteristic, except for younger women of whom 47 % exert highest peak values in the end-range pronation angle. Both relative pronator and supinator strength are dependent on sex (P < 0.05). Relative pronator strength is also affected by joint angle x sex (P < 0.0001) and joint angle x sex x age (P < 0.05) interactions. Beside age effects on all range of motion parameters, pronation range of motion is influenced by a sex x age interaction (P < 0.05).

CONCLUSIONS

Age- and sex-related differences in both subtalar strength profile and range of motion have to be considered when testing strength across subtalar range of motion. Younger females have higher pronator strength capacity in the most pronated joint angle, which may be due in part to their greater subtalar joint range of motion compared to the other groups. In the most supinated position both pronator and supinator strength capacity is reduced in younger females compared to younger males.

Reliability of isometric subtalar pronator and supinator strength testing

BACKGROUND

Due to the specific anatomy of the subtalar joint with its oblique axis, isometric pronator and supinator strength is not well documented. The purpose of this study was to determine intra- and between-session reliability of pronator and supinator strength and lower leg muscle activity measurements during maximum voluntary isometric contractions (MVIC).

METHODS

Pronator and supinator peak torques (PT), with and without supplementary visual muscle strength biofeedback (FB), and muscular activities of peroneus longus (PL) and tibialis anterior (TA) were assessed twice 3 days apart by the same examiner in 21 healthy young male adults (mean age: 27.6 years; SD = 3.9). Limits of agreement (LoA) and minimum detectable change (MDC) were evaluated.

RESULTS

By applying FB, reliability of both pronator and supinator PT was improved: LoA were reduced from 32% to 26% and from 20% to 18% and MDC from 20% to 15% and from 16% to 12% in supinator and pronator PT, respectively. Learning effects in pronator and supinator PT (p < 0.05), which were present without FB, were eliminated using FB. Except for TA during pronation, muscle activities showed low reliability indicated by LoA of 51% to 79%.

CONCLUSIONS

Using supplementary biofeedback, isometric subtalar pronator and supinator strength testing is reliable in healthy subjects. LoA of 18% and 26% have to be exceeded for pronator and supinator PT, respectively, to detect relevant effects in repeated measures.

Return to play after an ankle sprain: guidelines for the podiatric physician

The ankle sprain is the most common injury in sport and has a high incidence of long-term disability. This disability may be partly due to early return to sport before ligament healing has been completed. The podiatric physician can follow sound guidelines for making a return-to-play decision for athletes suffering from an ankle sprain. The decision-making process requires the podiatric physician to monitor the rehabilitation process and then administer patient self-reported questionnaires as well as functional performance tests to assess the status of ankle function after injury.

Biomechanical symmetry in elite rugby union players during dynamic tasks: an investigation using discrete and continuous data analysis techniques

Background

While measures of asymmetry may provide a means of identifying individuals predisposed to injury, normative asymmetry values for challenging sport specific movements in elite athletes are currently lacking in the literature. In addition, previous studies have typically investigated symmetry using discrete point analyses alone. This study examined biomechanical symmetry in elite rugby union players using both discrete point and continuous data analysis techniques.

Methods

Twenty elite injury free international rugby union players (mean ± SD: age 20.4 ± 1.0 years; height 1.86 ± 0.08 m; mass 98.4 ± 9.9 kg) underwent biomechanical assessment. A single leg drop landing, a single leg hurdle hop, and a running cut were analysed. Peak joint angles and moments were examined in the discrete point analysis while analysis of characterising phases (ACP) techniques were used to examine the continuous data. Dominant side was compared to non-dominant side using dependent t-tests for normally distributed data or Wilcoxon signed-rank test for non-normally distributed data. The significance level was set at α = 0.05.

Results

The majority of variables were found to be symmetrical with a total of 57/60 variables displaying symmetry in the discrete point analysis and 55/60 in the ACP. The five variables that were found to be asymmetrical were hip abductor moment in the drop landing (p = 0.02), pelvis lift/drop in the drop landing (p = 0.04) and hurdle hop (p = 0.02), ankle internal rotation moment in the cut (p = 0.04) and ankle dorsiflexion angle also in the cut (p = 0.01). The ACP identified two additional asymmetries not identified in the discrete point analysis.

Conclusions

Elite injury free rugby union players tended to exhibit bi-lateral symmetry across a range of biomechanical variables in a drop landing, hurdle hop and cut. This study provides useful normative values for inter-limb symmetry in these movement tests. When examining symmetry it is recommended to incorporate continuous data analysis techniques rather than a discrete point analysis alone; a discrete point analysis was unable to detect two of the five asymmetries identified.

Electronic supplementary material

The online version of this article (doi:10.1186/s13102-015-0006-9) contains supplementary material, which is available to authorized users.

Persistence of long term isokinetic strength deficits in subjects with lateral ankle sprain as measured with a protocol including maximal preloading

BACKGROUND

The assessment of muscle function is a cornerstone in the management of subjects who have sustained a lateral ankle sprain. The ankle range of motion being relatively small, the use of preloading allows to measure maximal strength throughout the whole amplitude and therefore to better characterize ankle muscles weaknesses. This study aimed to assess muscle strength of the injured and uninjured ankles in subjects with a lateral ankle sprain, to document the timeline of strength recovery, and to determine the influence of sprain grade on strength loss.

METHODS

Maximal torque of the periarticular muscles of the ankle in a concentric mode using a protocol with maximal preloading was tested in 32 male soldiers at 8 weeks and 6 months post-injury.

FINDINGS

The evertor muscles of the injured ankles were weaker than the uninjured ones at 8 weeks and 6 months post-injury (P<0.0001, effect size=0.31-0.42). Muscle weaknesses also persisted in the plantarflexors of the injured ankles at 8 weeks (P=0.0014, effect size=0.52-0.58) while at 6 months, only the subjects with a grade II sprain displayed such weaknesses (P<0.0001, effect size 0.27-0.31). The strength of the invertor and dorsiflexor muscles did not differ between sides.

INTERPRETATION

The use of an isokinetic protocol with preloading demonstrates significant but small strength deficits in the evertor and plantarflexor muscles. These impairments may contribute to the high incidence of recurrence of lateral ankle sprain in very active individuals.

The effectiveness of strain counterstrain in the treatment of patients with chronic ankle instability: A randomized clinical trial

STUDY DESIGN

Randomized clinical trial.

OBJECTIVE

To determine the effect of strain counterstrain (SCS) on dynamic balance and subjective sense of instability in individuals with chronic ankle instability (CAI). Although many studies have been published on CAI, the cause for this common clinical dysfunction remains inconclusive. No studies have assessed the effectiveness of SCS on CAI.

METHODS

At baseline all participants completed a demographic questionnaire, the star excursion balance test (SEBT), and the foot and ankle ability measure (FAAM). Following the baseline evaluation, participants were randomized into the SCS experimental group (EG) (n = 13) or the sham SCS group (SG) (n = 14). All participants received the assigned treatment once a week for 4 weeks and participated in a prescribed exercise program. At week 4, all participants repeated the outcome measures and completed a global rating of change (GROC) form. The primary aim was examined with a two-way analysis of variance (ANOVA).

RESULTS

A significant group-by-time interaction was found for seven directions in the SEBT (P<0.031). For subjective measures, no significant group-by-time interaction was found for the FAAM (P>0.548), but the GROC revealed a significant difference (P = 0.014) in the mean score for the EG (3.92±1.66) when compared to the SG (2.43±1.66).

DISCUSSION

Although SCS may not have an effect on subjective ankle function in individuals with CAI, preliminary evidence suggests that SCS may lead to an improvement in dynamic ankle stability and the subjective sense of ankle instability.

LEVEL OF EVIDENCE

Therapy, Level 1b.

Lateral Ankle Sprain and Chronic Ankle Instability: A Critical Review

Many studies investigated the contributing factors of chronic ankle instability, but a consensus has not yet been obtained. The objective of this critical review is to provide recent scientific evidence on chronic ankle instability, including the epidemiology and pathology of lateral ankle sprain as well as the causative factors of chronic ankle instability. We searched MEDLINE from 1964 to December 2013 using the terms ankle, sprain, ligament, injury, chronic, functional, mechanical, and instability. Lateral ankle sprain shows a very high recurrence rate and causes considerable economic loss due to medical care, prevention, and secondary disability. During the acute phase, patients with ankle sprain demonstrate symptoms such as pain, range of motion deficit, postural control deficit, and muscle weakness, and these symptoms may persist, leading to chronic ankle instability. Although some agreement regarding the effects of chronic ankle instability with deficits in postural control and/or concentric eversion strength exists, the cause of chronic ankle instability remains controversial.

LEVELS OF EVIDENCE

Therapeutic Level IV: Review of Level IV studies.

Shank-Rearfoot Joint Coupling with Chronic Ankle Instability

Chronic ankle instability (CAI) results in longstanding symptoms and subjective feelings of “giving way” following initial ankle sprain. Our purpose was to identify differences in joint coupling and variability between shank internal/external rotation and rearfoot inversion/eversion throughout the gait cycle of CAI subjects and healthy controls. Twenty-eight young adults participated (CAI, n = 15, control, n = 13). Kinematics were collected while walking and jogging on a treadmill. A vector coding method in which direction (θ) and magnitude of the angle-angle relationship and stride-to-stride variability (VCV) in shank-rearfoot coupling were calculated. In walking, the CAI group demonstrated lower θ, indicating a greater proportion of rearfoot-to-shank motion, compared with the control group in early and late swing. The CAI group had higher magnitude, indicating greater combined motion between the two segments, in early swing, but lower magnitude, indicating less combined motion, during late swing. The CAI group also had lower VCV measures, indicating less stride-to-stride variability during stance. In jogging, the CAI group had lower θ measures than the control group during stance and swing. Differences in shank-rearfoot coupling of the CAI group may be related to changes in sensorimotor control and lead to further instances of instability.

Individuals with diminished hip abductor muscle strength exhibit altered ankle biomechanics and neuromuscular activation during unipedal balance tasks

Coordinated control of the hip and ankle is important for maintaining postural stability. The purpose of the study was to compare postural stability between individuals with contrasting hip abductor strength during unipedal balance tasks and to determine whether diminished hip abductor strength results in greater utilization of the ankle strategy to maintain balance. Forty-five females (276±35 years) participated in the study. Participants were ranked based on their isometric hip abductor muscle strength. The top 33% of the participants were categorized as the strong group (n=15) and the lower 33% as the weak group (n=15). Each subject performed a static and a dynamic unipedal balance task, during which mean COP displacement, peak ankle invertor and evertor moments, and neuromuscular activation of the lower leg muscles were assessed. Two-way mixed analyses of variance tests with task as a repeated factor were performed to detect the effects of task and group on the variables of interest. When averaged across tasks, mean medial-lateral COP displacement was significantly greater in the weak group (136±117 vs. 98±60 mm, p=0.05). The weak group also exhibited greater peak ankle invertor and evertor moments (0.31±0.10 vs. 0.25±0.11 Nm/kg, p=0.03; 0.04±0.06 vs. -0.02±0.07 Nm/kg, p=0.01), and increased peroneus longus activation (46±12 vs. 36±15%, p<0.01). Our results demonstrate that individuals with diminished hip abductor muscle strength demonstrated decreased medial-lateral postural stability, and exhibited a shift toward utilizing an ankle strategy to maintain balance during unipedal tasks.

Differences in lateral drop jumps from an unknown height among individuals with functional ankle instability

CONTEXT

Functional ankle instability (FAI) is a debilitating condition that has been reported to occur after 20% to 50% of all ankle sprains. Landing from a jump is one common mechanism of ankle injury, yet few researchers have explored the role of visual cues and anticipatory muscle contractions, which may influence ankle stability, in lateral jumping maneuvers.

OBJECTIVE

To examine muscle-activation strategies between FAI and stable ankles under a lateral load and to evaluate the differences in muscle activation in participants with FAI and participants with stable ankles when they were unable to anticipate the onset of lateral loads during eyes-open versus eyes-closed conditions.

DESIGN

Case-control study.

SETTING

Controlled laboratory setting.

PATIENTS OR OTHER PARTICIPANTS

A total of 40 people participated: 20 with FAI and 20 healthy, uninjured, sex- and age-matched persons (control group).

INTERVENTION(S)

Participants performed a 2-legged lateral jump off a platform onto a force plate set to heights of 35 cm or 50 cm and then immediately jumped for maximal height. They performed jumps in 2 conditions (eyes open, eyes closed) and were unaware of the jump height when their eyes were closed.

MAIN OUTCOME MEASURE(S)

Amplitude normalized electromyographic (EMG) area (%), peak (%), and time to peak in the tibialis anterior (TA), peroneus longus (PL), and lateral gastrocnemius (LG) muscles were measured.

RESULTS

Regardless of the eyes-open or eyes-closed condition, participants with FAI had less preparatory TA (t158 = 2.22, P = .03) and PL (t158 = 2.09, P = .04) EMG area and TA (t158 = 2.45, P = .02) and PL (t158 = 2.17, P = .03) peak EMG than control-group participants.

CONCLUSIONS

By removing visual cues, unanticipated lateral joint loads occurred simultaneously with decreased muscle activity, which may reduce dynamic restraint capabilities in persons with FAI. Regardless of visual impairment and jump height, participants with FAI exhibited PL and TA inhibition, which may limit talonavicular stability and intensify lateral joint surface compression and pain.

National Athletic Trainers' Association position statement: conservative management and prevention of ankle sprains in athletes

OBJECTIVE

To present recommendations for athletic trainers and other allied health care professionals in the conservative management and prevention of ankle sprains in athletes.

BACKGROUND

Because ankle sprains are a common and often disabling injury in athletes, athletic trainers and other sports health care professionals must be able to implement the most current and evidence-supported treatment strategies to ensure safe and rapid return to play. Equally important is initiating preventive measures to mitigate both first-time sprains and the chance of reinjury. Therefore, considerations for appropriate preventive measures (including taping and bracing), initial assessment, both short- and long-term management strategies, return-to-play guidelines, and recommendations for syndesmotic ankle sprains and chronic ankle instability are presented.

RECOMMENDATIONS

The recommendations included in this position statement are intended to provide athletic trainers and other sports health care professionals with guidelines and criteria to deliver the best health care possible for the prevention and management of ankle sprains. An endorsement as to best practice is made whenever evidence supporting the recommendation is available.

Fatigue of the hip abductors results in increased medial-lateral center of pressure excursion and altered peroneus longus activation during a unipedal landing task

BACKGROUND

Previous studies have reported that diminished hip abductor muscle strength is associated with a loss of frontal plane postural stability and increased risk for ankle sprain. The purpose of this study was to determine whether hip abductor fatigue results in compensatory changes in neuromuscular activation of the peroneus longus (an important lateral stabilizer of the ankle) during a unipedal landing task.

METHODS

Thirty healthy females performed a unipedal landing task before and after completing a hip abductor fatigue protocol. Paired t-tests were used to assess changes in medial-lateral center of pressure displacement, and EMG (electromyographic) amplitude of the peroneus longus following hip abductor fatigue. Changes in peroneus longus onset timing also were assessed.

FINDINGS

Following the hip abductor fatigue protocol, participants exhibited increased mean center of pressure displacement (7.7 (1.5) vs. 9.2 (2.0) cm, P<0.01), and increased EMG amplitude of peroneus longus (0.75 (0.18) vs. 0.86 (0.21), P<0.01) during the deceleration phase of landing. Post-fatigue, significantly earlier peroneus longus onset timing prior to landing was observed (88.9 (24.9) vs. 121.9 (25.7) ms, P<0.01).

INTERPRETATION

The increased EMG amplitude and earlier onset of the peroneus longus appears to be a protective compensatory adaptation to stabilize the ankle in response to frontal plane postural instability induced by hip abductor fatigue.

The varus ankle and instability

Varus ankle associated with instability can be simple or complex. Multiple underlying diseases may contribute to this complex pathologic entity. These conditions should be recognized when attempting proper decision-making. Treatment options range from conservative measures to surgical reconstruction. Whereas conservative treatment might be a possible approach for patients with simple varus ankle instability, more complex instabilities require extensive surgical reconstructions. However, adequate diagnostic workup and accurate analysis of varus ankle instability provide a base for the successful treatment outcome.