Difference in postural control between patients with functional and mechanical ankle instability

Effects of isokinetic and proprioceptive training after lateral ankle ligament reconstruction: A case report

INTRODUCTION

Lateral ankle ligament reconstruction (LALR) is fundamental to avoid instability and the risk of osteoarthritis. After surgery, deficits in muscular strength and the proprioceptive system lead to functional changes. This study aimed to investigate if proprioceptive and isokinetic training can be incorporated to manage a professional soccer player after LALR.

METHOD

A 25-year-old professional soccer player, who injured his right ankle while playing, participated in the study. An MRI revealed partial rupture of the anterior talofibular ligament and associated fracture of the posterolateral distal fibular. Three months after the reconstruction surgery, the participant performed 20 sessions of isokinetic training along with 10 proprioceptive exercises. Outcomes were isokinetic inversion and eversion variables in concentric mode at 60, 120, and 240°/s (during the isokinetic phase - sustained velocity), postural sway (assessed in single-limb stance, using a force platform), and physical function (Foot and Ankle Ability Measure (FAAM) and the Lower Extremity Functional Scale (LEFS)).

RESULTS

Post-treatment, the sustained velocity increased by ∼6% and decreased by 3% in the other isokinetic phases in inversion and eversion. At 60°/s, the Peak Torque/Body Mass for the evertor muscle was 30% higher post-treatment. Center of Pressure (CoP) data with eyes open showed a decrease for anteroposterior dispersions and displacement. The FAAM (sports sub-section) and LEFS increased by 15.6 and 9 points, respectively.

CONCLUSION

Isokinetic and proprioceptive training improved postural control parameters, physical function, and inversion and eversion isokinetic variables in a professional soccer player after lateral ligament reconstruction.

A modified "outside-in" Broström-Gould procedure yielding favorable outcomes for the management of chronic lateral ankle instability-a retrospective study with mid-term follow-up

Purpose: There are various surgical interventions available for the management of Chronic lateral ankle instability (CLAI). The Broström-Gould procedure has gained widespread recognition among foot and ankle specialists for its favorable surgical outcomes. However, with advancements in anatomical understanding and medical technology, further enhancements to the effectiveness of the Gould procedure are warranted. This study introduces a all-inside modified "outside-in" Broström -Gould procedure as an alternative approach for addressing lateral ankle instability. Methods: From August 2020 to October 2022, 40 patients with lateral ankle instability who underwent arthroscopic repair of the modified "outside-in" Broström-Gould procedure were retrospectively analyzed. All patients received standard non-surgical treatment before surgery for more than 6 months without symptom relief. Visual Analogue Scale (VAS) and American Orthopaedic Foot and Ankle Society (AOFAS) and Karlsson-Peterson score were used to evaluate the postoperative effect. Results: All patients were followed up for (14.62 ± 2.04) months. One year after operation, all patients could walk normally, ankle instability sensation disappeared, varus stress test and anterior drawer test were negative. The VAS , AOFAS and Karlsson-Peterson scores of all patients were significantly better compared with those before operation, and the difference between before and after operation was statistically significant. Conclusions: The modified "outside-in" Broström-Gould procedure can effectively treat CLAI, which can obtain satisfactory results. The procedure is straightforward, the impact is minimal, and the aesthetics are pleasing.

Bilateral Sensorimotor Impairments in Individuals with Unilateral Chronic Ankle Instability: A Systematic Review and Meta-Analysis

BACKGROUND

Chronic ankle instability (CAI) is manifested by sensorimotor impairments in the sprained ankle, including deficits in sensation, motor function, and central integration or processing. These impairments have a significant impact on physical activities and daily life. Recently, some studies have suggested that bilateral deficits were observed in unilateral CAI, but contradictory evidence disputes this finding. Therefore, the objective of this study was to investigate whether bilateral sensorimotor deficits presented in individuals with unilateral CAI.

METHODS

Without language restriction, the following databases were retrieved from database inception up until 3 November 2023, including PubMed, WOS, EMBASE, Cochrane, SPORTDiscus and CINAHL. Case-control and cross-sectional studies that investigated bilateral sensorimotor functions in individuals with unilateral CAI were included. Sensorimotor functions contained static and dynamic balance, functional performance, muscle strength and activation, as well as sensation. Outcome measures contained centre-of-pressure parameters, normalised reach distance, activation time and magnitude of muscle, sensory errors and threshold. The risk of bias and quality assessment of included studies were evaluated using a standardised tool recommended by the Cochrane Collaboration and the Epidemiological Appraisal Instrument, respectively. To explore the potential bilateral deficits associated with unilateral CAI, a comprehensive meta-analysis was conducted using Review Manager version 5.4. The analysis compared the injured limb of unilateral CAI with healthy controls and the uninjured limb with healthy controls. The main focus of this study was to investigate the differences between the uninjured limb and healthy controls. A random-effects model was employed and effect sizes were estimated using the standardised mean difference (SMD) with 95% confidence intervals (CIs). Effect sizes were deemed as weak (0.2-0.5), moderate (0.5-0.8), or large (> 0.8).

RESULTS

A total of 11,442 studies were found; 30 studies were contained in the systematic review and 20 studies were included in the meta-analysis. Compared with healthy controls, those with unilateral CAI presented weak to moderate impairments in their uninjured limbs in static balance with eyes open (SMD = 0.32, 95% CI: 0.08 to 0.56), functional performance (SMD = 0.37; 95% CI: 0.08 to 0.67), kinesthesia (SMD = 0.52; 95% CI: 0.09 to 0.95) and tibialis anterior activation (SMD = 0.60, 95% CI: 0.19 to 1.01). There were no significant differences in other comparisons between the uninjured limb and healthy controls.

CONCLUSIONS

Patients with unilateral CAI may present bilateral deficits in static balance with eyes open, functional performance and kinaesthesia. However, further evidence is required to confirm this point due to limited studies included in some analyses and small effect size.

REGISTRATION

The protocol was registered in the International Prospective Register of Systematic Reviews platform (CRD: 42,022,375,855).

A novel method of assessing balance and postural sway in patients with hypermobile Ehlers-Danlos syndrome

Patients with hypermobile Ehlers-Danlos syndrome (hEDS) frequently suffer from poor balance and proprioception and are at an increased risk for falls. Here we present a means of assessing a variety of balance and postural conditions in a fast and non-invasive manner. The equipment required is commercially available and requires limited personnel. Patients can be repeatedly tested to determine balance and postural differences as a result of disease progression and aging, or a reversal following balance/exercise interventions.

Posturography measures in specific ballet stance position discriminate ballet dancers with different occurrences of musculoskeletal injuries

BACKGROUND

This study aimed to identify the postural sway variables that can distinguish between ballet dancers with high and low occurrences of musculoskeletal injuries.

METHODS

Fourteen professional ballet dancers were assigned to a high-occurrence group (N = 5, reports >2 injuries in the previous 6-months) or a low-occurrence group (N = 9, reports ≤1 injury). Center-of-pressure (COP) data were acquired using a force platform during the following tasks: single-leg stance with eyes open, single-leg stance with eyes closed, and demi-pointe stance with eyes open. The COP standard deviation (SD) and range (RA) in both the medial-lateral (ML) and anterior-posterior (AP) directions were estimated. Between-group comparisons were made through Welch's t-tests for unequal sample size along the effect size measure (Cohen's d). Spearman's rho was used to estimate the association between the number of injuries and the COP variables. The statistical threshold was set at 1%.

RESULTS

A between-group effect was found only for the demi-pointe stance, with large effects for SDML (P = 0.006, d = 1.7), RAAP (P = 0.006, d = 1.7), and RAML (P = 0.005, d = 1.7). An inverse relationship was found between the number of injuries and the demi-pointe's COP range in both directions (Spearman's rho from -0.681 to -0.726, P = 0.007).

CONCLUSIONS

COP measures taken in ballet-specific positions can distinguish between dancers with a high and low occurrence of musculoskeletal injuries. Suggestions are made to include ballet-specific tasks in the functional assessments of professional dancers.

Inertial Sensor-Based Assessment of Static Balance in Athletes with Chronic Ankle Instability

The Balance Error Scoring System (BESS), a subjective examiner-based assessment, is often employed to assess postural balance in individuals with chronic ankle instability (CAI); however, inertial sensors may enhance the detection of balance deficits. This study aimed to compare the BESS results between the CAI and healthy groups using conventional BESS scores and inertial sensor data. The BESS test (six conditions: double-leg, single-leg, and tandem stances on firm and foam surfaces, respectively) was performed for the CAI (n = 16) and healthy control (n = 16) groups with inertial sensors mounted on the sacrum and anterior shank. The BESS score was calculated visually by the examiner by counting postural sway as an error based on the recorded video. The root mean square for resultant acceleration (RMS_acc) in the anteroposterior, mediolateral, and vertical directions was calculated from each inertial sensor affixed to the sacral and shank surfaces during the BESS test. The mixed-effects analysis of variance and unpaired t-test were used to assess the effects of group and condition on the BESS scores and RMS_acc. No significant between-group differences were found in the RMS_acc of the sacral and shank surfaces, and the BESS scores (P > 0.05), except for the total BESS score in the foam condition (CAI: 14.4 ± 3.7, control: 11.7 ± 3.4; P = 0.039). Significant main effects of the conditions were found with respect to the BESS scores and RMS_acc for the sacral and anterior shank (P < 0.05). The BESS test with inertial sensors can detect differences in the BESS conditions for athletes with CAI. However, our method could not detect any differences between the CAI and healthy groups.

Functional effects of arthroscopic modified Broström procedure on lateral ankle instability: A pilot study

BACKGROUND

This study aims to assess the mechanical and functional effects of the arthroscopic modified Broström procedure (AMBP) on patients with lateral ankle instability.

METHODS

Eight patients with unilateral ankle instability treated with AMBP and eight healthy subjects were recruited. Healthy subjects, preoperative and one-year postoperative patients were assessed using outcome scales and the Star Excursion Balance Test (SEBT) for dynamic postural control. One-dimensional statistical parametric mapping was performed to compare ankle angle and muscle activation curve during stair descent.

RESULTS

The patients with lateral ankle instability showed good clinical outcomes and increased posterior lateral reach during the SEBT after the AMBP (p = 0.046). The medial gastrocnemius activation after initial contact was reduced (p = 0.049), and the peroneal longus activation after initial contact was promoted (p = 0.014).

CONCLUSION

The AMBP has functional effects of promoting dynamic postural control and peroneal longus activation within one year of follow-up, which can benefit patients with functional ankle instability. However, the medial gastrocnemius activation was unexpectedly reduced post operation.

Open Evaluation of the Peroneal Tendons Should Be Considered in Patients With Chronic Lateral Ankle Instability Undergoing Ankle Arthroscopy With Lateral Ankle Stabilization

Peroneal tendon pathology is commonly associated with chronic lateral ankle instability. Foot and ankle surgeons often rely on preoperative magnetic resonance imaging (MRI) for identification of related pathology and surgical planning in these patients. The purpose of this study was to assess the ability of preoperative MRI to accurately detect peroneal tendon pathology in patients with chronic lateral ankle instability. Consecutive surgical cases involving arthroscopic evaluation and management of lateral ankle instability sequelae were evaluated retrospectively. Preoperative MRI were compared to intraoperative findings in order to determine the sensitivity, specificity, positive and negative predictive values. Eighty-two patients met inclusion criteria, 58 females and 24 males. The average age at the time of surgery was 46 years (range 13-75). Peroneal tendon pathology was identified intraoperatively in 76 (92.7%) patients and on MRI in 40 (48.8%) patients. The most commonly identified pathologies were tenosynovitis, tendinopathy and longitudinal split/tear, with the peroneus brevis tendon being most commonly involved. MRI was 38.7% specific, 50.0% sensitive, had a positive predictive value of 92.5%, and a negative predictive value of 7.1%. While MRI is a helpful study for evaluation of co-pathologies and surgical planning in patients with lateral ankle instability, procedural selection should not be solely based on MRI results, and the peroneal tendons should be evaluated intraoperatively in patients undergoing arthroscopic procedures for lateral ankle instability.

Kinetic Effects of 6 Weeks' Pilates or Balance Training in College Soccer Players with Chronic Ankle Instability

Lateral ankle sprain (LAS) is a common sports injury that frequently occurs in active individuals. LAS is characterized by a high recurrence rate, with a large proportion of patients progressing to chronic ankle instability (CAI). Pilates exercises have provided positive results in health care and in rehabilitation. This study compared Pilates training (PT) with traditional balance training (BT) in patients with CAI. Fifty-one college football players with CAI, divided into PT (n = 26) and BT (n = 25) groups, were included in the study. The groups performed PT or BT training as assigned, three times per week for 6 weeks. Isokinetic ankle strength, one-leg hop tests, Y-balance test (YBT), and foot and ankle outcome score (FAOS) were evaluated before and after training. There were considerable improvements in both the PT and BT groups after training. Group and time comparisons revealed that the PT group achieved better triple hop test results than the BT group, whereas the BT group exhibited a greater improvement in YBT posteromedial and posterolateral reach distances. In athletes with CAI, both PT and BT effectively improved symptoms and function. These findings suggest that ankle strength, balance, and core stability should be comprehensively evaluated and targeted in CAI rehabilitation programs.

Epidemiology and Outcomes of Ankle Injuries in the National Football League

Background:

Traumatic ankle injuries are commonly complicated by persistent symptoms and the development of chronic ankle instability.

Purpose:

To describe the epidemiology of ankle injuries in the National Football League (NFL) and investigate the effects that ankle injuries have on performance metrics in the years after injury.

Study Design:

Descriptive epidemiologic study.

Methods:

Ankle injuries sustained by NFL players during the 2015-2016, 2016-2017, and 2017-2018 seasons were identified using the Pro Football Reference database. Cumulative incidence was calculated, and demographic identifiers were collected for each injury. The return-to-play (RTP) rate was also recorded. For each player who met inclusion for the performance analysis, power rating (PR) was calculated for the preinjury season (Y–1) and 2 postinjury seasons (Y+1 and Y+2) as follows: PR = ( offensive yards/10) + ( total touchdowns × 6) + ( combined tackles) + ( sacks × 2) + ( interceptions × 2). Mean PRs were calculated for each season as well as the percentage change and mean difference in PR between Y–1 and Y+1 (ΔPR1%, ΔPR1) and between Y–1 and Y+2 (ΔPR2%, ΔPR2). Subgroup analyses of PR were performed by player position, injury type, and years of experience.

Results:

Overall, 668 ankle injuries were identified, with an average cumulative incidence across the 3 seasons of 11.2% and RTP rate of 91%. Of those injuries, 159 met inclusion criteria for the PR analysis. The mean overall PR (96.95 in Y–1) declined 22% in Y+1 to 76.10 (–20.85 [95% CI, –13.82 to –27.89]; P < .001) and 27% in Y+2 to 70.93 (–26.02 [95% CI, –18.04 to –34.00]; P < .001). The mean PR per game played (6.70 in Y–1) decreased 14% in Y+1 to 5.75 (–0.95 [95% CI, –0.56 to –1.34]; P < .001) and 17% in Y+2 to 5.54 (–1.16 [95% CI, –0.63 to –1.62]; P < .001).

Conclusion:

It was found that ankle injuries hampered the performance of NFL players, even multiple years after the injury occurred, despite a relatively high RTP rate. There was a decrease in total games played after ankle injuries as well as a decreased performance output per game played.

A quantitative evaluation of the individual components contributing to the functional ankle instability in patients with modified Broström procedure

Residual functional ankle instability regardless of the restoration of mechanical stability after the lateral ligament repair or reconstruction can cause recurrent sprain. The purpose of this study was to identify the sequential changes of joint-position sense, peroneal strength, postural control, and functional performance ability after the modified Broström procedure (MBP) for chronic ankle instability. A total of 46 patients (46 ankles) underwent the MBP for chronic ankle instability were eligible for this study and were followed for 1 year postoperatively. The changes of joint-position sense and peroneal strength were periodically evaluated with an isokinetic dynamometer. Postural control ability was evaluated using a one-leg stance test with eyes closed. The functional performance ability examination comprised a one-leg hop test, a 6-meter hop test, and a cross 3-meter hop test. The error in joint-position sense significantly improved from a mean 4.3º to 2.8º (p < .001). Peak torque for eversion significantly improved from a mean 18.2 Nm to 21.2 Nm (p = .024). Balance retention time significantly improved from a mean 4.7 seconds to 6.4 seconds (p < .001). Among the functional performance tests, only the one-leg hop test showed a significant improvement postoperatively (p = .031). At 1 year postoperatively, the recovery ratios compared to the unaffected ankle were 67.9% in joint-position sense (p < .001), 86.9% in peroneal strength (p = .012), and 74.4% in postural control (p < .001) with significant side-to-side differences. Although joint-position sense, peroneal strength, postural control, and functional performance ability were significantly improved after the MBP, recovery ratios compared to the unaffected ankle were insufficient up to 1 year postoperatively.

An association between excessive valgus hindfoot alignment and postural stability during single-leg standing in adolescent athletes

BACKGROUND

Diminished balance is associated with the incidence of ankle and lower extremity injuries in adolescents. Although flexible flatfoot is a common foot condition in pediatric and adolescent populations, the association between balance control and foot morphology remain unclear in adolescent athletes.

METHODS

Rearfoot angle in the double-limb standing position, body mass index (BMI), and isometric muscle strength related to the knee joint were retrospectively reviewed in 101 adolescent athletes (75 boys and 26 girls) with a mean age of 14.0 years (range 12-17). Postural stability during single-leg standing on static and dynamic platforms was investigated using Balance System SD in 119 feet without functional ankle instability. The participants were divided according to their rearfoot angle into control (less than 7°) and valgus (greater than or equal to 7°) groups. The measured parameters were compared between the control and valgus groups using Welch's t-test, and P values < 0.05 were considered statistically significant. Multiple regression analysis was conducted to identify the factors that significantly influenced postural control.

RESULTS

The average rearfoot angle was 4.6° in all participants. An excessive valgus rearfoot angle was detected in 53 feet (26.2%). No significant difference was found between the groups in terms of BMI and isometric knee muscle strength. Although no statistical differences were observed in postural stability on the static platform between the control and valgus groups, the valgus group demonstrated poorer postural stability for single-leg standing on the dynamic platform. Multiple regression analysis revealed that BMI and rearfoot angle were significantly associated with a poor postural control on the dynamic platform.

CONCLUSIONS

Our findings suggest that excessive rearfoot valgus specifically contributes to the deterioration of postural stability in adolescent athletes, and that rearfoot alignment should be evaluated for the adolescent population to prevent sports-related lower extremity injury.

Proprioception and neuromuscular control at return to sport after ankle surgery with the modified Broström procedure

The modified Broström procedure (MBP) is an initial treatment for symptomatic chronic ankle instability (CAI) patients. This study aimed to compare the proprioception and neuromuscular control ability of both affected and unaffected ankles at the time of return to sports after MBP for patients with scores of normal controls. 75 individuals (40 who underwent MBP, 35 normal controls) participated. The dynamic balance test scores were significantly higher in the affected ankle of the patients than in the controls (1.5 ± 0.6° vs. 1.1 ± 0.4°, p < 0.003). The time to peak torque for dorsiflexion (60.8 ± 13.9 ms vs. 52.2 ± 17.5 ms, p < 0.022) and eversion (68.9 ± 19.1 ms vs. 59.3 ± 21.1 ms, p < 0.043) was significantly delayed in the affected ankle of the patients than in the controls. The dynamic balance test and time to peak torque in CAI patients remained significantly reduced at the time of return-to-sport after MBP. Clinicians and therapists should be aware of potential deficits in proprioception and neuromuscular control when determining the timing of return to sports after MBP.

The changes of joint-position sense, peroneal strength, postural control, and functional performance ability after the modified Broström procedure for chronic ankle instability

Purpose: Residual functional ankle instability regardless of the restoration of mechanical stability after the lateral ligament repair or reconstruction can cause recurrent sprain. The purpose of this study was to identify the sequential changes of joint-position sense, peroneal strength, postural control, and functional performance ability after the modified Broström procedure (MBP) for chronic ankle instability. Methods: A total of 46 patients (46 ankles) who underwent the MBP for chronic ankle instability were eligible for this study and were followed up for 1 year postoperatively. The changes of joint-position sense and peroneal strength were periodically evaluated with an isokinetic dynamometer. Postural control ability was evaluated using a one-leg stance test with eyes closed. The functional performance ability examination comprised a one-leg hop test, a six-meter hop test, and a cross three-meter hop test. Results: The error in joint-position sense significantly improved from a mean 4.3° to 2.8° (p < 0.001). Peak torque for eversion significantly improved from a mean 18.2 Nm to 21.2 Nm (p = 0.024). Balance retention time significantly improved from a mean 4.7 s to 6.4 s (p < 0.001). Among the functional performance tests, only the one-leg hop test showed a significant improvement postoperatively (p = 0.031). At 1 year postoperatively, the recovery ratios compared to the unaffected ankle were 67.9% in joint-position sense (p < 0.001), 86.9% in peroneal strength (p = 0.012), and 74.4% in postural control (p < 0.001), with significant side-to-side differences. Conclusion: Although joint-position sense, peroneal strength, postural control, and functional performance ability were significantly improved after the MBP, recovery ratios compared to the unaffected ankle were insufficient up to 1 year postoperatively. Level of Evidence: Level IV (prospective case series).

Reliability and usefulness of the single leg heel raise balance test in patients with chronic ankle instability

We aimed to analyze the differences in static (including conventional and modified [single-leg heel-raise balance]) and dynamic postural stability and muscle endurance between patients with chronic ankle instability (CAI) and healthy controls, and to determine the reliability and usefulness of the single-leg heel-raise balance test in patients with CAI. In total, 26 patients with CAI and 26 healthy controls were enrolled. Postural stability was assessed using a postural stabilometry system. Muscle endurance was measured in dorsiflexion and plantarflexion using an isokinetic device. Modified static postural stability (P < 0.001) and dynamic postural stability (P < 0.001) were significantly poorer in the affected ankles of patients with CAI than in the controls. Plantarflexion endurance was significantly lower in the affected ankles of the patients with CAI than in the controls (P = 0.023). Modified static postural stability significantly correlated with plantarflexion endurance in both groups (CAI group: r = - 0.470, P = 0.015; healthy controls group: r = - 0.413, P = 0.036). Plantarflexion endurance was a significant risk factor for modified static postural stability in both the CAI group (R² = 0.221, P = 0.015) and healthy controls (R² = 0.170, P = 0.036). Given the reliability of the modified static postural stability test, clinicians and therapists should consider using it to assess improvements in postural stability and muscle endurance in patients with CAI before and after rehabilitation.

The fibula and talus position difference in functional and mechanical ankle instability: MRI findings

PURPOSE

This study aimed to use MRI to evaluate the fibula and talus position difference in functional and mechanical ankle stability patients.

METHODS

61 and 68 patients with functional and mechanical instability, and 60 healthy volunteers were involved. Based on the axial MRI images, the rotation of the talus was identified through the Malleolar Talus Index (MTI). The position relative to the talus (Axial Malleolar Index, AMI) and medial malleolus (Intermalleolar Index, IMI) were used to evaluated the displacement of the fibula.

RESULTS

Post hoc analysis showed that the values of malleolar talus index was significantly larger among mechanical instability (89.18° ± 2.31°) than that in functional instability patients (86.55° ±61.65°, P < 0.001) and healthy volunteers (85.59° ± 2.42°, P < 0.001). The axial malleolar index of the mechanical instability patients (11.39° ± 1.41°) were significantly larger than healthy volunteers (7.91° ± 0.83°) (P < 0.0001). There were no statistically significant differences in the above three indexes between the functional instability patients and healthy volunteers.

CONCLUSION

The functional instability patients didn't have a posteriorly positioned fibula and an internally rotated talus. The malleolar talus index was significantly larger among mechanical instability patients than that in functional instability patients. Increased malleolar talus index may become a new indirect MRI sign for identifying functional and mechanical instability patients.

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

This revised clinical practice guideline (CPG) addresses the distinct but related lower extremity impairments of those with a first-time lateral ankle sprain (LAS) and those with chronic ankle instability (CAI). Depending on many factors, impairments may continue following injury. While most individuals experience resolution of symptoms, complaints of instability may continue and are defined as CAI. The aims of the revision were to provide a concise summary of the contemporary evidence since publication of the original guideline and to develop new recommendations or revise previously published recommendations to support evidence-based practice. J Orthop Sports Phys Ther 2021;51(4):CPG1-CPG80. doi:10.2519/jospt.2021.0302.

Chronic ankle instability is associated with proprioception deficits: A systematic review and meta-analysis

BACKGROUND

Acute ankle injury causes damage to joint mechanoreceptors and deafferentation and contributes to proprioception deficits in patients with chronic ankle instability (CAI). We aimed to explore whether deficits of proprioception, including kinesthesia and joint position sense (JPS), exist in patients with CAI when compared with the uninjured contralateral side and healthy people. We hypothesized that proprioception deficits did exist in patients with CAI and that the deficits varied by test methodologies.

METHODS

The study was a systematic review and meta-analysis. We identified studies that compared kinesthesia or JPS in patients with CAI with the uninjured contralateral side or with healthy controls. Meta-analyses were conducted for the studies with similar test procedures, and narrative syntheses were undertaken for the rest.

RESULTS

A total of 7731 studies were identified, of which 30 were included for review. A total of 21 studies were eligible for meta-analysis. Compared with the contralateral side, patients with CAI had ankle kinesthesia deficits in inversion and plantarflexion, with a standardized mean difference (SMD) of 0.41 and 0.92, respectively, and active and passive JPS deficits in inversion (SMD = 0.92 and 0.72, respectively). Compared with healthy people, patients with CAI had ankle kinesthesia deficits in inversion and eversion (SMD = 0.64 and 0.76, respectively), and active JPS deficits in inversion and eversion (SMD = 1.00 and 4.82, respectively). Proprioception deficits in the knee and shoulder of patients with CAI were not statistically significant.

CONCLUSION

Proprioception, including both kinesthesia and JPS, of the injured ankle of patients with CAI was impaired, compared with the uninjured contralateral limbs and healthy people. Proprioception varied depending on different movement directions and test methodologies. The use of more detailed measurements of proprioception and interventions for restoring the deficits are recommended in the clinical management of CAI.

Demographic Predictors of Concomitant Osteochondral Lesion of the Talus in Patients With Chronic Lateral Ankle Instability

Background:

Osteochondral lesion of the talus (OLT) is commonly found as a concomitant pathologic lesion in a large proportion of patients with chronic lateral ankle instability (CLAI). This study investigated which characteristics in a patient with CLAI increase the risk for OLT.

Methods:

Three hundred sixty-four patients who underwent a modified Broström operation for their CLAI were reviewed retrospectively. The characteristics of each patient and variables associated with OLTs were investigated. Statistical analyses were performed to determine the effect of each potential predictor on the incidence of OLT, and to evaluate the associations between the patient characteristics and variables associated with OLTs.

Results:

Patients with OLTs were more frequently female (female vs male: 63.1% vs 43.9%, P = .003). In addition, the lesion sizes were larger in female patients (female vs male: 113.9 ± 24.9 mm² vs 100.7 ± 18.0 mm², P = .002), and medial lesions were more common in female patients (female vs male; 93.3% vs 81.8%, P = .036). The lesion sizes were larger in patients with a wider talar tilt angle (P < .001), and patients with a medial OLT showed a wider talar tilt angle (12.0 ± 2.0 degrees vs 10.3 ± 2.2 degrees, P = .002).

Conclusion:

In this CLAI patient cohort, we found female patients to be at greater risk for OLTs than male patients. Furthermore, CLAI female patients with concomitant OLT had on average a larger lesion size, more frequent OLT medial position, and were associated with wider talar tilt angles, suggesting that females had more intrinsic ankle instability than males.

Level of Evidence:

Level IV, retrospective case series.

Open Brostrom for Lateral Ligament Stabilization

PURPOSE OF REVIEW

Lateral ankle ligament sprains are one of the most commonly reported injuries in high-level athletes and the general population. Unfortunately, up to 40% of these can go on to develop chronic lateral ankle instability which in the right circumstances requires surgical intervention. The purpose of this review is to present the gold standard surgical treatment for chronic lateral instability with anatomic ligament repair and to highlight the techniques, outcomes, and importance of anatomy when considering surgical treatment.

RECENT FINDINGS

Recent and remote literature agrees that the initial treatment for chronic ankle instability is non-operative rehabilitation. In the cases where this fails, the gold standard of surgical treatment is open anatomic repair using the Brostrom-Gould technique which stands out as having very good results over the course of time. Recent studies have shown equally good outcomes with arthroscopy as well as with internal brace devices, and both techniques show potential for earlier rehabilitation. In those with contraindications for anatomic repair including innate soft tissue laxity, high BMI, and in the revision setting, anatomic ligament reconstruction is an appropriate surgical option. Open modified Brostrom lateral ligament repair continues to be the preferred method of surgical treatment for chronic lateral ligament instability. In the setting of new modifications and techniques, long-term outcome studies are necessary to identify both their usefulness in long term and to compare them to the open surgery outcomes. It would be useful to standardize rehabilitation protocols as well as return to sport metrics in order to better evaluate outcomes moving forward.

Functional deficits in chronic mechanical ankle instability

BACKGROUND

The interaction of functional and mechanical deficits in chronic ankle instability remains a major issue in current research. After an index sprain, some patients develop sufficient coping strategies, while others require mechanical support. This study aimed to analyze persisting functional deficits in mechanically unstable ankles requiring operative stabilization.

METHODS

We retrospectively analyzed the functional testing of 43 patients suffering from chronic, unilateral mechanical ankle instability (MAI) and in which long-term conservative treatment had failed. Manual testing and arthroscopy confirmed mechanical instability. The functional testing included balance test, gait analysis, and concentric-concentric, isokinetic strength measurements and was compared between the non-affected and the MAI ankles.

RESULTS

Plantarflexion, supination, and pronation strength was significantly reduced in MAI ankles. A sub-analysis of the strength measurement revealed that in non-MAI ankles, the peak pronation torque was reached earlier during pronation (maximum peak torque angle at 20° vs. 14° of supination, p < 0.001). Furthermore, active range of motion was reduced in dorsiflexion and supination. In balance testing, patients exhibited a significant increased perimeter for the injured ankle (p < 0.02). During gait analysis, we observed an increased external rotation in MAI (8.7 vs. 6.8°, p<0.02).

CONCLUSIONS

This study assesses functional deficits existent in a well-defined population of patients suffering from chronic MAI. Impairments of postural sway, gait asymmetries, and asymmetric isokinetic strength can be observed despite long-term functional treatment. The finding that pronation strength is particularly reduced with the foot in a close-to-accident position indicates potential muscular dysfunction in MAI. Possibly, these deficits alongside the underlying mechanical instability characterize patients requiring mechanical stabilization.

The Role of the Podiatrist in Assessing and Reducing Fall Risk: An Updated Review

Falls present a tremendous challenge to health care systems. This article reviews the literature from the previous 5 years (2014-2019) in terms of methods to assess fall risk and potential steps that can be taken to reduce fall risk for patients visiting podiatric clinics. With regard to assessing fall risk, we discuss the role of a thorough medical history and podiatric assessments of foot problems and deformities that can be performed in the clinic. With regard to fall prevention we consider the role of shoe modification, exercise, pain relief, surgical interventions, and referrals.

Leg stiffness control during drop landing movement in individuals with mechanical and functional ankle disabilities

Purpose: Individuals with mechanical ankle instability (MAI) and functional ankle instability (FAI) present with residual movement dysfunctions after an initial lateral ankle sprain. This study investigated leg stiffness control to determine how behavioural characteristics between MAI and FAI differ during single-leg drop landing movement. Methods: Thirty individuals (10 with MAI, 10 with FAI, and 10 healthy controls) participated in this study. During single-leg drop landing movement, we estimated dimensionless leg stiffness, peak vertical force (PVF), change in the displacement of leg movement, loading rate, angular joint movement, and internal joint moment for impaired and unimpaired legs, respectively. Univariate one-way analysis of variance was used for each dependent variable across leg conditions. Results: The MAI group had lower dimensionless leg stiffness with greater change in the displacement of leg movement for the impaired leg than the FAI and control groups. Moreover, reduced leg stiffness was associated with greater hip joint flexion movement in the MAI group, whereas ankle dorsiflexion movement increased to decrease the leg stiffness in the FAI and control groups. Conclusion: These findings indicate that lower leg stiffness in the MAI group than in the FAI group may be attributed to compensatory actions to minimise reliance on their ankle movement after landing.

Individuals with recurrent ankle sprain demonstrate postural instability and neuromuscular control deficits in unaffected side

PURPOSE

To compare proprioception, postural stability, and neuromuscular control between patients with mechanical laxity and recurrent ankle sprain.

METHODS

Among 86 patients with ankle instability, 45 patients had mechanical laxity (mean age 27.2 ± 7.0 years) and 41 had recurrent ankle sprain (mean age 25.1 ± 9.2 years). Both the affected and unaffected ankles of each patient were evaluated. Proprioception and neuromuscular control tests were conducted using an isokinetic machine, and postural stability was tested using a postural stabilometry system.

RESULTS

Proprioception was not significantly different between the unaffected or affected ankles of the mechanical laxity group compared with those of the recurrent ankle sprain group (n.s). Static and dynamic postural stability and neuromuscular control were similar in the affected ankles between the two groups (n.s). However, postural stability (static, overall: p = 0.009, anterior-posterior: p = 0.028, medial-lateral: p = 0.022; dynamic, overall: p = 0.012, anterior-posterior: p = 0.004, medial-lateral: p = 0.001) and neuromuscular control (inversion: p = 0.031, eversion: p = 0.039, dorsiflexion: p = 0.029, plantarflexion: p = 0.035) were significantly decreased in the unaffected ankles of the recurrent ankle sprain group compared with those of the mechanical laxity group.

CONCLUSION

The unaffected ankles of the recurrent ankle sprain group showed significant decreases in both postural stability and neuromuscular control compared with the mechanical laxity group. Clinicians and therapists should consider unaffected ankle rehabilitation in patients with recurrent ankle sprain to prevent future sprain events.

LEVEL OF EVIDENCE

Case-control study, III.

Correlation Between Joint-Position Sense, Peroneal Strength, Postural Control, and Functional Performance Ability in Patients With Chronic Lateral Ankle Instability

BACKGROUND

The first aim of this study was to evaluate the side-to-side difference of joint-position sense, peroneal strength, postural control, and functional performance ability in patients with chronic lateral ankle instability. The second aim was to identify the correlation between various components contributing to the functional ankle instability (FAI).

METHODS

Thirty-five patients to be scheduled for the modified Broström procedure for chronic ankle instability were analyzed. Joint-position sense and peroneal strength were measured with an isokinetic dynamometer. Postural control ability was evaluated using the modified Romberg test. The functional performance test consisted of the 1-leg hop test, 6-meter hop test, and cross 3-m hop test. Spearman's correlation coefficient (r) was calculated to determine the linear association between the individual components of the FAI.

RESULTS

Except for the 6-m and cross 3-m hop tests, most examination tools for the FAI demonstrated significant side-to-side differences compared with the unaffected ankle. Spearman's correlation analysis revealed that individual components (joint-position sense, peroneal strength, postural control, and functional performance ability) of the FAI were significantly associated with one another, except between peroneal strength and postural control ability (r = 0.21, P = .195).

CONCLUSION

Joint-position sense, peroneal strength, postural control ability, and 1-leg hop test demonstrated significant side-to-side differences in patients with chronic lateral ankle instability. Individual components contributing to the FAI were significantly correlated with one another, except between peroneal strength and postural control ability. Postural control evaluation using the modified Romberg test could substitute for dynamometer testing, with convenience and economic advantage.

LEVEL OF EVIDENCE

Level IV, prospective case series.

Effect of Lateral Ligament Augmentation Using Suture-Tape on Functional Ankle Instability

BACKGROUND:

Although lateral ligament augmentation using suture-tape has been effective for restoration of mechanical ankle stability, few data are available regarding changes of peroneal strength, proprioception, and postural control. The aim of this study was to determine effects of suture-tape augmentation on functional ankle instability (FAI).

METHODS:

Twenty-four patients who underwent suture-tape augmentation were eligible and were followed more than 2 years postoperatively. Functional outcomes were evaluated with the Cumberland Ankle Instability Tool (CAIT), Foot and Ankle Ability Measure (FAAM). Changes of peroneal strength, proprioception and postural control were analyzed with an isokinetic dynamometer and a modified Romberg test.

RESULTS:

CAIT and FAAM (average of daily and sports activity scores) significantly improved to average 27.2 points and 86.7 points, respectively, at final follow-up. Peak torque for eversion in 60 degrees/s angular velocity significantly improved to 10.6 Nm at final follow-up. Deficit ratio of peak torque for eversion significantly improved from mean 39.5% to 20.9%, and significant side-to-side difference was revealed ( P < .001). There were no significant differences in joint position sense. A significant improvement in balance retention time was revealed at final follow-up, and the relative deficit ratio compared to the unaffected side was 30.9%.

CONCLUSIONS:

Patient-reported functional outcomes significantly improved after lateral ligament augmentation using suture-tape. Although this procedure demonstrated significant effects on FAI based on improvement of isokinetic peroneal strength and postural control, recovery rates compared to the unaffected side were not significant at the intermediate-term follow-up. In addition, there was no positive effect on proprioception of the ankle.

LEVEL OF EVIDENCE:

Level IV, prospective case series.

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.

Nonlinear Dynamic Measures for Evaluating Postural Control in Individuals With and Without Chronic Ankle Instability

This study aimed to compare time-to-boundary and sample entropy during a single-leg balance task between individuals with chronic ankle instability (CAI), lateral ankle sprain copers, and healthy controls. Twenty-two participants with CAI, 20 lateral ankle sprain copers, and 24 healthy controls performed a single-leg balance task during an eyes-closed condition. Participants with CAI exhibited lower time-to-boundary values compared with lateral ankle sprain copers and healthy controls. However, we did not find differences in sample entropy variables between cohorts. A decrease in time-to-boundary values in participants with CAI indicated that CAI may constrain the ability of the sensorimotor system to maintain the center of pressure within the boundaries of the base of support. However, the regularity of the center of pressure velocity time series appears not to be altered in the CAI cohort in this study.

Factors contributing to chronic ankle instability: a protocol for a systematic review of systematic reviews

BACKGROUND

Ankle sprains are a significant clinical problem. Researchers have identified a multitude of factors contributing to the presence of recurrent ankle sprains including deficits in balance, postural control, kinematics, muscle activity, strength, range of motion, ligament laxity and bone/joint characteristics. Unfortunately, the literature examining the presence of these factors in chronic ankle instability (CAI) is conflicting. As a result, researchers have attempted to integrate this evidence using systematic reviews to reach conclusions; however, readers are now faced with an increasing number of systematic review findings that are also conflicting. The overall aim of this review is to critically appraise the methodological quality of previous systematic reviews and pool this evidence to identify contributing factors to CAI.

METHODS

A systematic review will be conducted on systematic reviews that investigate the presence of various deficits identified in CAI. Databases will be searched using pre-determined search terms. Reviews will then be assessed for inclusion based on the set eligibility criteria. Two independent reviewers will assess the articles for inclusion before evaluating the methodological quality and presence of bias of the included studies; any disagreements will be resolved by discussion between reviewers to reach consensus or by a third reviewer. Data concerning the specific research question, search strategy, inclusion/exclusion criteria, population, method and outcomes will be extracted. Findings will be analysed with respect to the methodological quality of the included reviews.

DISCUSSION

It is expected that this review will clarify the cause of contradicting findings in the literature and facilitate future research directions.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016032592 .

The improvement of postural control in patients with mechanical ankle instability after lateral ankle ligaments reconstruction

PURPOSE

Lateral ankle sprain is the most common injury. A previous study demonstrated that patients with mechanical ankle instability suffered deficits in postural control, indicating that structural damage of the lateral ankle ligaments may produce a balance deficit. The purpose of this study was to confirm that lateral ligaments reconstruction could improve postural control in patients with mechanical ankle instability.

METHODS

A total of 15 patients were included in the study. Each patient had a history of an ankle sprain with persistent symptoms of ankle instability and a positive anterior drawer test and had been treated nonoperatively for at least 3 months. All patients were diagnosed with lateral ankle ligaments tear by ultrasonography and magnetic resonance imaging. They underwent arthroscopic debridement and open lateral ankle ligaments reconstruction with a modified Broström procedure. One day before and 6 months after the operation, all of the participants underwent single-limb postural sway tests. The anterior drawer test and the American Orthopedic Foot and Ankle Society scale score were used to evaluate the clinical results in these patients.

RESULTS

At 6 months after the operation, with the patients' eyes closed, there was significantly decreased postural sway in the anteroposterior direction, the circumferential area, and the total path length on the operated ankles compared with those measurements before the operation. With eyes open, however, no difference was found in postural sway before and after the operation.

CONCLUSIONS

Postural control was improved by reconstructing the lateral ligaments.

LEVEL OF EVIDENCE

IV.