Predictors of chronic ankle instability: Analysis of peroneal reaction time, dynamic balance and isokinetic strength

Effects of Peroneus Brevis versus Peroneus Longus Muscle Training on Muscle Function in Chronic Ankle Instability: A Randomized Controlled Trial

Chronic ankle instability (CAI) is a common injury that can occur in daily life or sporting events. Injuries to the anterior talofibular, posterior talofibular, and calcaneofibular ligaments are common, and the core of rehabilitation training involves strengthening the peroneus muscle. Many studies on rehabilitation training have focused on strengthening the peroneus brevis muscle, and few studies have focused on specific training to strengthen the peroneus longus muscle. Therefore, this study aims to investigate changes in the symptoms and functions of patients by applying training to strengthen the peroneus longus and peroneus brevis muscles. Home-based training and mobile monitoring were utilized for 12 weeks, divided into peroneus brevis training (PBT) and peroneus longus training (PLT), in 52 adult males with CAI. Participation was voluntary, with enrollment done through a bulletin board, and intervention training allocation was randomly assigned and conducted in a double-blind manner. This study was registered as a trial protocol (KCT 0008478). Foot and ankle outcome scores (FAOS), isokinetic ankle strength tests, and Y-balance tests were performed before and after the intervention. Both PLT and PBT significantly improved in FAOS, inversion, and eversion at angular velocities of 30°/s and 120°/s and in the anterior and posterolateral directions of the Y-balance test (p < 0.05). Interaction effects by time and group were not significant for the FAOS (p > 0.05). However, PLT improved eversion muscle strength and muscle power to a greater degree, compared with PBT, in the anterior and posterolateral directions of the Y-balance test (p < 0.05). In conclusion, both PLT and PBT were effective for CAI patients; in addition, PLT had greater potential for improving strength and balance.

Insufficient recovery of proprioception in chronic ankle instability after surgical restabilization: A systematic review

Surgical repair or reconstruction of the lateral ligaments for patients with chronic ankle instability (CAI) could, logically, restore the proprioception of ankle through retensing receptors. To validate this hypothesis, seven databases were systematically searched, and thirteen studies comprising a total of 347 patients with CAI were included. Although five studies reported improved proprioceptive outcomes after surgeries, the other five studies with between-limb/group comparisons reported residual deficits at final follow-up, which does not consistently support proprioceptive recovery after existing surgical restabilization for CAI. More controlled studies are needed to provide evidence-based protocols to improve proprioceptive recovery after ankle restabilization for CAI.

Investigating the value of balance and proprioception scores to predict lower limb injuries in professional judokas

We investigated the ability of balance and proprioception screening tests to predict lower limb injuries in professional male judokas. Fifty-three male judokas of the national teams (Mean ± SD, age 18.68 ± 3.08 years, weight 75.34 ± 11.62 kg, height 175.28 ± 7.24 cm) participated in this study. Limits of stability (LOS), single leg stability (SLS), and knee joint position sense (JPS) was recorded as the screening tests before starting the 10 month follow up. Lower limb injury was recorded all through the follow up. Fifteen lower limb sport injuries were recorded for 53 judokas during the follow-up recordings. Significant accuracy of SLS, overall bilateral ratio (AUC 0.646, 95% CI 0.452-0.839, p = 0.046), as well as JPS 60° bilateral ratio (AUC 0.657, 95% CI 0.480-0.834, p = 0.044), and LOS overall (AUC 0.696, 95% CI 0.551-0.840, p = 0.031) were revealed discriminating between injured and uninjured judokas. The optimum cut-off of SLS, overall bilateral ratio, JPS 60° bilateral ratio, and LOS overall associated with belonging to uninjured judokas group was ≤ 1.15%, ≤ 1.09%, and ≤ 1.09 respectively (sensitivity, 0.763, 0.711, 0.789 respectively; specificity, 0.600). Although the absolute unilateral balance and proprioception scores were almost the same between injured and non-injured judokas, the bilateral ratio of both these indices were different between the two groups. Lower limbs bilateral balance and proprioception asymmetries is a more important risk factor than the absolute unilateral balance and proprioception scores for sustaining lower limb injuries in professional male judokas. Medical professionals and coaches are suggested to use these findings as pre-participation screening tools identify injury-prone athletes.

Acute short term effects of endurance and resistance training on balance control in patients with diabetic peripheral neuropathy

PURPOSE

Exercise training have numerous beneficial effects on the complications of diabetic peripheral neuropathy. Exercise training may cause immediate effects on balance control in DPN patients. This study aims to assess the Acute Short Term effects of endurance and resistance exercise training on balance control in DPN patients.

METHODS

In this study, 11 patients with DPN and 11 healthy subjects participated. Patients and healthy subjects did endurance and resistance training in two separate exercise sessions. Dynamic balance and functional balance test were assessed before and after the interventions. Independent t-test was used to compare balance indices before and after training, the intervention effects were examined using ANOVA repeated measure test. The statistical significance level was set at p < 0.05.

RESULTS

The results showed that dynamic and functional balance in DPN patients were significantly lower than in healthy subjects. Anterior-posterior stability and total stability indices and functional balance test deteriorated significantly after training.

CONCLUSION

Endurance or resistance training may lead to acute disturbance of dynamic and functional balance in DPN patients. Hence, immediately after exercise, patients with diabetes are at an increased risk of falling, therefore, preventive considerations are necessary.

Biomechanical improvement of anterior talofibular ligament by augmentation repair of ligament advance reinforcement system: a cadaver study

BACKGROUND

Ankle sprain are one of the most frequent sports injuries. Some individuals will develop chronic lateral ankle instability (CLAI) after ankle sprain and suffer from recurrent ankle sprain. Current surgical treatment of CAI with anterior talofibular ligament (ATFL) rupture fails to restore the stability of the native ATFL. Ligament Advance Reinforcement System (LARS) augmentation repair of ATFL was developed to improve its primary stability after repaired.

METHODS

This study was performed to evaluate whether LARS augmentation repair of ATFL had similar stability as the modified Broström repair and the intact ATFL to maintain ankle construct stability. Standardized surgical techniques were performed on eighteen fresh frozen cadaver ankle specimens. The intact ATFL group has just undergone an ATFL exploratory surgery. The modified Broström procedure is based on anatomical repair of the ATFL with a 2.9 mm suture anchor, and the LARS procedure is an augmentation procedure of the ATFL using LARS ligaments based on the modified Broström procedure. A dynamic tensile test machine was used to assess load-to-failure testing in the three groups. The ultimate failure load and stiffness were calculated and reported from the load-displacement curve. A one-way analysis of variance was used to detect significant differences (p < 0.05) between the LARS augmentation repair, the modified Broström repair and the intact ATFL, followed by least significant difference (LSD) post-hoc tests.

RESULTS

The LARS augmentation repair group showed an increased in ultimate failure to load and stiffness compared to the other two groups. There were no significant differences in ultimate failure to load and stiffness between the modified Broström and the intact ATFL, the LARS ligament for ATFL augmentation allows for improved primary stability after repair and reduced stress on the repaired ATFL, which facilitates healing of the remnant ligament.

CONCLUSIONS

The LARS augmentation repair of ATFL represents a stable technique that may allow for the ankle stability to be restored in patients with CAI after surgery.

Lateral wedge insoles and their use in ankle instability

The aim of the present study is to assess the immediate effects of applying lateral wedge insoles of different heights (0.00, 0.3, 0.4, and 0.6 cm) in patients with chronic ankle instability (CAI) in normal and supinated feet during a Star Excursion Balance Test (SEBT) and in the reflex response of Peroneus Longus (PL), Peroneus Brevis (PB), and Tibialis Anterior (TA) over a 30° inversion of the feet. The effects of the height of the wedges were assessed using a double-blind, crossover design. In total, 25 participants were allocated into two groups, depending on the foot posture (Normal = 12, Supinated = 13) and performed the tests in a random fashion. Reaction time (RT) of stabilizing muscles of the ankle was measured using superficial electromyography (EMG) and postural balance with the SEBT. Foot posture did not show any significant effects on the analyzed variables. Nonetheless, the use of a 0.3 cm external rearfoot wedge (PB p = 0.002; PL p = 0.066 and TA p = 0.006) and 0.6 cm (PB p = 0.043; PL p = 0.058 and TA p = 0.071) reduces RT in stabilizing muscles of the ankle and improves results in SEBT, except for the anterolateral direction, in subjects with CAI. Therefore, our results suggest that the use of lateral wedge insoles could reduce RT and improve dynamic balance in chronic ankle instability.

Current Challenges in Chronic Ankle Instability: Review and Perspective

Chronic ankle instability (CAI) is common, disabling, and represents a significant socioeconomic burden. Current treatment options are not adequately efficacious. CAI is multifaceted, yet it is commonly addressed in terms of either mechanical instability or functional impairment. Both are inherently linked. Basic research must be conducted to foster reliable translational research encompassing both mechanical and functional aspects. A review was conducted to identify CAI risk factors for inclusion in future studies, and we offer here opinions and perspectives for future research.

Dynamic postural control in individuals with and without chronic ankle instability-do the modified star-excursion balance test and jump-landing stabilization have the same control mechanism?

OBJECTIVE

To examine the relationship between two dynamic postural tasks in subjects with and without chronic ankle instability (CAI).

DESIGN

Cross-sectional study.

SETTING

Biomechanics lab.

PARTICIPANTS

Thirty subjects with CAI and 30 healthy controls.

MAIN OUTCOME MEASURE

Performance of two dynamic postural control tests: the modified Star-Excursion Balance Test (mSEBT) and an assessment of a single limb jump-landing on a force plate that yielded two outcomes: time to stabilization (TTS) and the absolute average force in the mediolateral plane during the first 0.4 s after landing (AAF_ML).

RESULTS

In the CAI group, a significant correlation was found between the mSEBT score and the AAF_ML (ρ = -0.54, p < 0.01), but not between the mSEBT or TTS or between the AAF_ML and the TTS. However, in the control group, a significant correlation was found between AAF_ML and the TTS (ρ = 0.43, p < 0.05), but not between the mSEBT and TTS or between the mSEBT and AAF_ML.

CONCLUSION

These results suggest that there is no association between the different dynamic balance tasks. The different pattern of association in individuals with CAI may indicate altered central neural control. Clinicians and researchers should therefore not use a single task to assess dynamic postural control.

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.

A randomized controlled trial comparing rehabilitation with isokinetic exercises and Thera-Band strength training in patients with functional ankle instability

BACKGROUND

Although muscle strength training is a prevalent treatment for patients with functional ankle instability (FAI), previous investigations on the efficacy have yielded conflicting results.

OBJECTIVE

This study aims to compare the efficacy of 6-week isokinetic strength training and Thera-Band strength training on improving ankle strength, dynamic balance ability, and function in individuals with FAI.

METHODS

Fifty-two FAI patients were randomized into two treatment groups: an isokinetic strength training (IST, n = 26) group and a Thera-Band resistance training (TBT, n = 26) group. The IST group engaged in isokinetic concentric strength training with inversion, eversion, dorsiflexion, and plantar flexion, whereas the TBT group engaged in progressive resistance training with Thera-Band three times per week for six weeks. Before and after the training, an isokinetic concentric strength test of the involved ankle joint, Star Excursion Balance Test (SEBT), and Cumberland Ankle Instability Tool (CAIT) function assessment were performed.

RESULTS

After six weeks of intervention, the strength of inversion and eversion was significantly improved in both the IST and TBT groups (p < 0.05), with the IST group exhibiting a significant (p < 0.05) improvement when compared to the TBT group. The SEBT and CAIT results were significantly (p < 0.05) improved in the IST group compared to the TBT group.

CONCLUSIONS

The six-week of isokinetic strength training is more effective than the Thera-Band progressive resistance training in improving the physical function of FAI patients.

CLINICAL TRIAL REGISTRATION NUMBER

This randomized controlled clinical trial has been registered in the China Clinical Trial Registry (ChiCTR2100044444) https://www.google.com/search?client=firefox-b-d&q=ChiCTR2100044444.

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.

Acute lateral ankle sprain alters muscle and tendon properties: Case series

BACKGROUND

Acute lateral ankle sprain (LAS) is the most prevalent acute sports trauma. Ankle muscle atrophy and tendon volume decrease have not been analyzed concomitantly with functional impairment and pain following LAS. The objective of the present study was to investigate muscle cross-section area (CSA), tendon CSA and volume, ankle function, and pain in individuals who suffered an acute LAS.

METHODS

A series of cases, cross-sectional study with 20 participants who suffered moderate (grade II) and severe (grade III) acute LAS was undertaken. CSA for muscles (Tibialis Posterior, Fibularis, and Soleus) and tendons (Tibialis Anterior, Tibialis posterior, Fibularis, and Achilles), and volume were measured by magnetic resonance imaging (MRI) less than 48 h (baseline) and 6-weeks after the acute LAS. Ankle function (Cumberland Ankle Instability Tool [CAIT] and Foot and Ankle Outcome Score [FAOS]), ankle mechanical instability (Anterior Drawer Test [ADT]), and pain were also assessed.

RESULTS

All tendons and muscles showed a significant reduction in CSA and volume between baseline and 6-weeks (P < .001). A significant decrease in ankle function was observed 6 weeks after the LAS, along with a reduction in pain and mechanical instability (P = .001). Regarding sprain magnitude, the only difference observed was greater atrophy in muscle CSA in participants with grade III ankle sprain.

CONCLUSION

Patients with acute LAS showed atrophy of ankle muscles and decreased tendon volume and CSA, followed by function impairments at 6-week follow-up.

LEVEL OF EVIDENCE

IV, Case series study.

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.

Dynamic reach deficits in those with chronic ankle instability: A systematic review and meta-analysis

OBJECTIVE

The purpose of this review with meta-analyses was to determine the dynamic reach differences 1) between chronic ankle instability (CAI) and uninjured individuals, 2) between the limbs of an individual with CAI, and 3) between the uninvolved CAI limb and the healthy control limb across all possible reach directions of the Star Excursion Balance Test (SEBT).

METHODS

PubMed, CINAHL, SPORTDiscus, and Scopus databases were searched up to October 2021. Data were extracted from the retained studies and underwent methodological quality assessment and meta-analysis using random-effect models.

RESULTS

After screening, 33 articles were included for the analyses. In all possible SEBT reach directions, the CAI group demonstrated significantly decreased normalized dynamic reach distances relative to the uninjured control group (SMDs: -0.66 to -0.48, p ≤ 0.05). Similarly, the involved CAI limb demonstrated significantly decreased normalized dynamic reach distances relative to the uninvolved CAI limb (SMDs: -0.61 to -0.33, p ≤ 0.05). However, no differences were noted between the uninvolved CAI limb and the healthy control limb (SMDs: -0.22 to 0.09, p ≥ 0.13).

CONCLUSIONS

Our findings were that the involved limb of those with CAI has dynamic postural deficits relative to (i) an uninjured control group and (ii) relative to their uninvolved limb. However, the uninvolved limb of the CAI group does not differ from an uninjured control group in any reach direction.

Perception of stability correlates with objective performance of dynamic stability for people with chronic ankle instability

Purpose

Lateral ankle sprains are one of the most prevalent musculoskeletal injuries, with one of the highest recurrence rates. One in five people develops chronic ankle instability (CAI) after a lateral ankle sprain. CAI is mainly described as a subjective phenomenon, but is associated with recurrent symptoms, reduced dynamic stability, and reduced physical activity and quality of life. Understanding the relationship between perception of stability and effect on performance for people with CAI could inform rehabilitative strategies in clinical practice. This study aimed to investigate the relationship between the perception of stability and objective performance of dynamic stability this population.

Methods

This study is a sub-analysis of data from four separate studies in Australia and the United Kingdom. Participants were screened and categorised as a CAI, coper, or healthy participant. Each participant completed the Star Excursion Balance Test (SEBT) and Cumberland ankle instability tool (CAIT). Distances reached in the anterior, posterior-medial, and posterior-lateral directions, and average, of the SEBT were analysed.

Results

Data from 95 participants with CAI, 45 copers, and 101 healthy participants was analysed. There was a significant moderate correlation between CAIT score and SEBT reach distance in all directions for the CAI group (p < 0.001). For copers, there was small significant correlation in the posterior-lateral direction (p < 0.05).

Conclusion

This study highlights the discrepancies between the perception of stability and objective dynamic stability, and reinforces the importance of using both types of measures for continual assessment in practice to optimise selecting rehabilitative strategies.

Muscle activations during functional tasks in individuals with chronic ankle instability: a systematic review of electromyographical studies

BACKGROUND

It has been reported that individuals with chronic ankle instability (CAI) show motor control abnormalities. The study of muscle activations by means of surface electromyography (sEMG) plays a key role in understanding some of the features of movement abnormalities.

RESEARCH QUESTION

Do common sEMG activation abnormalities and strategies exists across different functional movements?

METHODS

Literature review was conducted on PubMed, Web-of-Science and Cochrane databases. Studies published between 2000 and 2020 that assessed muscle activations by means of sEMG during any type of functional task in individuals with CAI, and used healthy individuals as controls, were included. Methodological quality was assessed using the modified Downs&Black checklist. Since the methodologies of different studies were heterogeneous, no meta-analysis was conducted.

RESULTS

A total of 63 articles investigating muscle activations during gait, running, responses to perturbations, landing and hopping, cutting and turning; single-limb stance, star excursion balance task, forward lunges, ball-kicking, y-balance test and single-limb squatting were considered. Individuals with CAI showed a delayed activation of the peroneus longus in response to sudden inversion perturbations, in transitions between double- and single-limb stance, and in landing on unstable surfaces. Apparently, while walking on ground there are no differences between CAI and controls, walking on a treadmill increases the variability of muscles activations, probably as a "safety strategy" to avoid ankle inversion. An abnormal activation of the tibialis anterior was observed during a number of tasks. Finally, hip/spine muscles were activated before ankle muscles in CAI compared to controls.

CONCLUSION

Though the methodology of the studies herein considered is heterogeneous, this review shows that the peroneal and tibialis anterior muscles have an abnormal activation in CAI individuals. These individuals also show a proximal muscle activation strategy during the performance of balance challenging tasks. Future studies should investigate whole-body muscle activation abnormalities in CAI individuals.

Comparison of EMG signal of the flexor hallucis longus recorded using surface and intramuscular electrodes during walking

The purpose of this study was to compare the use of intramuscular (iEMG) and surface (sEMG) electromyography electrodes to record flexor hallucis longus (FHL) muscle activity during walking, and describe the role of the FHL. Muscle activity was recorded in 12 participants using sEMG and iEMG during treadmill and overground walking. Inter-tester reliability for visual detection of onset and offset of muscle activity was high (ICC = 1.00). During the loading period, the number of bursts of muscle activity was statistically significantly greater using iEMG compared to sEMG when treadmill walking (p = 0.016), and the duration of muscle activity was significantly greater for iEMG (p = 0.01) on both walking surfaces. There were no differences for peak and mean root mean squared (p ≥ 0.07). The FHL activity observed during the loading period (heel strike to forefoot strike) supports the function of the FHL to act as a dynamic ankle stabiliser of the rearfoot, as well as contributing to propulsion during the latter part of stance. The choice of electrodes to detect FHL activity should be dependent on whether the loading and propulsive periods are of interest, and whether treadmill or overground walking will be examined.

Tensiomyographic Neuromuscular Response of the Peroneus Longus and Tibialis Anterior with Chronic Ankle Instability

This study aimed to investigate the muscle contractile response of the peroneus longus (PL) and tibialis anterior (TA) in groups with and without chronic ankle instability (CAI) using tensiomyography. Twenty-three adults, 12 with CAI and 11 healthy participants, participated in this study. All subjects underwent a tensiomyographic assessment of the PL and TA to measure delay time, contraction time and maximal displacement. The ankle evertor and invertor normalized peak torques, maximum work done and muscle thickness of the PL and TA were calculated. The delay time and contraction time of the PL in the CAI side were significantly higher than those in the healthy group (p < 0.05); however, no significant difference could be detected in the TA between groups. Furthermore, there was no significant difference in the normalized peak torques, maximum work done and muscle thickness of the PL and TA between groups. The CAI side demonstrated a delayed muscle contractile response of the PL when compared with the healthy group although there was no difference in muscle strength and muscle size. Clinicians should consider the muscle contractile response of the PL for rehabilitation of the ankle evertor with CAI.

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.

Functional Electrical Stimulation of Peroneal Muscles on Balance in Healthy Females

Balance improvement could contribute to ankle stability for the prevention of ankle sprains. Functional electrical stimulation (FES) is an effective way of augmenting muscle activity and improving balance. This study investigated the effect of FES of peroneal muscles on single-and double-leg balance. Fifteen healthy females (age = 23.1 ± 1.6 years, height = 1.63 ± 0.07 m, and weight = 63.7 ± 9.9 kg) performed single- and double-leg standing balance tests with eyes open and closed before and after 15-minute FES intervention during treadmill running at a comfortable, self-selected pace. FES of peroneal muscles was provided bilaterally, using an Odstock Dropped Foot Stimulator. The total excursion of the centre of pressure (COP) was calculated to assess the standing balance control ability. The total excursion of COP in single- and double-leg stance with eyes open reduced significantly after FES intervention by 14.7% (p < 0.001) and 5.9% (p = 0.031), respectively. The eyes-closed condition exhibited a 12.7% (p = 0.002) reduction in single-leg stance but did not significantly change in double-leg stance (p > 0.05). Limb preference did not account for balance postintervention. No significant difference in total excursion of COP was found between preferred and less preferred limbs with both visual conditions (p > 0.05). FES of peroneal muscles improved standing balance control with eyes open in double-leg and single-leg stance and with eyes closed in double-leg stance. The improvements in balance control with FES treatment did not vary concerning limb preference.

A review of the role of lower-leg strength measurements in ankle sprain and chronic ankle instability populations

Lower-leg strength training has been a cornerstone of ankle sprain and chronic ankle instability (CAI) rehabilitation and an important consideration for return-to-play in athletes with ankle injuries. The purpose of this literature review is to offer a contemporary, evidence-based overview of the role of ankle strength measurements as they relate to acute ankle sprain rehabilitation and those who have developed CAI. A comprehensive 20-year scan of the relevant research was conducted to assist us in providing this important update for clinicians and biomechanists working with patients and subjects with acute and chronic ankle sprains. While variability exists with measurement devices and methodology, strength assessment remains a critical component of ankle sprain and CAI treatment schemes. Helpful tips on obtaining and processing the most accurate strength assessments for lower-leg musculature are presented.

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.

Selected Tools for Assessing the Risk of Falls in Older Women

Methods

Fifty-five females were examined (May 2018-June 2019). Stabilographic examinations were performed with eyes open (EO) and closed (EC). An analysis of variance (ANOVA) and Spearman rank correlation were performed to determine the relationships and differences between the above tests.

Results

The results of the TUG correlate with the overall stability index (OSI) EO (r = 0.314), medial-lateral stability index (MLSI) EO (r = 0.297), and fall risk index (FRI6-2; r = 0.435) in stabilographic examinations and the FRT (r = −0.399). The results of the modified Unterberger test correlate with MLSI EO (r = 0.276), OSI EC (r = 0.310), and MLSI EC (r = 0.378). There are statistically significant differences between faller and nonfaller groups in TUG (p = 0.0068), FRT (p = 0.001), and MLSI EO (p = 0.0118).

Conclusions

The modified Unterberger test and TUG can be considered effective in functional FR assessment in older women. Using at least two different functional tests may improve the assessment of FR.

Comparison of the Strength and Electromyography of the Evertor Muscles With and Without Toe Flexion in Patients With Chronic Ankle Instability

BACKGROUND

Weakness of evertor strength is controversial in chronic ankle instability (CAI). Ankle evertor muscles are attached to the toe joints as well as to the metatarsal bone. Therefore, it is necessary to consider toe joint position for the measurement of evertor strength. The purpose of this study was to compare ankle evertor strength and muscle activity during eversion with and without toe flexion (TF) in individuals with CAI and individuals in a healthy group.

METHODS

Fifteen subjects with CAI and 15 healthy subjects participated in this study. Isometric ankle evertor strength and muscle activity of the peroneus longus (PL), peroneus brevis (PB), and extensor digitorum longus (EDL) were measured during eversion with and without TF.

RESULTS

The results indicated a significant interaction effect in evertor strength (P = .03) and no significant interaction effect on EMG of the PL (P = .08), PB (P = .12), and EDL (P = .28). However, measurements of muscle activity of the PL and PB between eversion with and without TF revealed a significant difference in the CAI group (P < .01) and no significant difference in the healthy group (PL: P = .07; PB: P = .13).

CONCLUSION

The results indicated that subjects with CAI had increased EDL compensation and reduced selective activation of the PL and PB during eversion.

CLINICAL RELEVANCE

Our findings suggest that clinicians should consider the activation of EDL when training the evertor of patients with CAI.

A Possible Mobile Health Solution in Orthopedics and Trauma Surgery: Development Protocol and User Evaluation of the Ankle Joint App

Background

Ankle sprains are one of the most frequent sports injuries. With respect to the high prevalence of ankle ligament injuries and patients’ young age, optimizing treatment and rehabilitation is mandatory to prevent future complications such as chronic ankle instability or osteoarthritis.

Objective

In modern times, an increasing amount of smartphone usage in patient care is evident. Studies investigating mobile health (mHealth)–based rehabilitation programs after ankle sprains are rare. The aim of this study was to expose any issues present in the development process of a medical app as well as associated risks and chances.

Methods

The development process of the Ankle Joint App was defined in chronological order using a protocol. The app’s quality was evaluated using the (user) German Mobile App Rating Scale (MARS-G) by voluntary foot and ankle surgeons (n=20) and voluntary athletes (n=20).

Results

A multidisciplinary development team built a hybrid app with a corresponding backend structure. The app’s content provides actual medical literature, training videos, and a log function. Excellent interrater reliability (interrater reliability=0.92; 95% CI 0.86-0.96) was obtained. The mean overall score for the Ankle Joint App was 4.4 (SD 0.5). The mean subjective quality scores were 3.6 (surgeons: SD 0.7) and 3.8 (athletes: SD 0.5). Behavioral change had mean scores of 4.1 (surgeons: SD 0.7) and 4.3 (athletes: SD 0.7). The medical gain value, rated by the surgeons only, was 3.9 (SD 0.6).

Conclusions

The data obtained demonstrate that mHealth-based rehabilitation programs might be a useful tool for patient education and collection of personal data. The achieved (user) MARS-G scores support a high quality of the tested app. Medical app development with an a priori defined target group and a precisely intended purpose, in a multidisciplinary team, is highly promising. Follow-up studies are required to obtain funded evidence for the ankle joints app’s effects on economical and medical aspects in comparison with established nondigital therapy paths.

Is chronic ankle instability associated with impaired muscle strength? Ankle, knee and hip muscle strength in individuals with chronic ankle instability: a systematic review with meta-analysis

OBJECTIVE

Determine whether impairments in lower limb muscle strength exist in individuals with chronic ankle instability (CAI) compared with uninjured controls.

DESIGN

Systematic review with meta-analysis.

DATA SOURCE

A comprehensive search of PubMed, Cochrane, CINAHL, Web of Science and EMBASE electronic databases from inception to 10 February 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Cross-sectional and case-control studies were included if they objectively measured lower limb muscle strength in individuals with CAI compared with controls. Risk of bias and quality of included studies were assessed. Data of included studies were extracted, and meta-analysis was conducted where appropriate.

RESULTS

12 397 unique studies were identified, of which 20 were included and 16 were eligible for meta-analysis. Reviewed studies clearly described the aim/hypothesis and main outcome measure, but most lacked sample size calculation and assessor blinding. Meta-analyses showed individuals with CAI had lower eccentric and concentric evertor strength (30 and 120°/s; Nm; standardised mean difference (SMD) between -0.73 and -0.95), eccentric invertor strength (60 and 120°/s; both Nm and Nm/kg; SMD between -0.61 and -1.37), concentric invertor strength (60 and 120°/s; Nm; SMD=-0.7) and concentric knee extensor strength (SMD=-0.64) compared with control participants. Ankle eccentric dorsiflexor strength was not different between groups. Although pooling was not possible, data from three separate studies indicated that hip flexor, abductor and external rotator strength, but not hip adductor and extensor strength, was lower in individuals with CAI than in control participants.

CONCLUSION

Individuals with CAI have ankle inversion and eversion strength deficits. Our data also point to differences between individuals with CAI and controls in hip and knee strength. These elements of the kinetic chain should be evaluated by clinicians who rehabilitate individuals with CAI.

PROSPERO REGISTRATION NUMBER

CRD42016037759.

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.

The Effect of Static Stretching of Peroneal and Tibialis Anterior Muscles on Reaction Time: A Randomized Controlled Study

OBJECTIVE

The aim of this study was to investigate the acute and chronic effects of static stretching on peroneal and tibialis anterior reaction characteristics.

DESIGN

All 23 participants who volunteered for this study were randomly divided into static (n = 12) and control (n = 11) groups. The subjects in the static stretching group performed stretching exercises for the ankle evertor and dorsiflexor muscles 5 days a week for 6 wks. Peroneal and tibialis anterior muscle reaction characteristics were evaluated at the beginning (2 times for acute effect) and end of this period. Electromyographic activity parameters of the muscles were measured using an ankle inversion tilting platform that simulated a sudden ankle inversion. The following were the four different ankle inversion conditions: (a) ankle-neutral, 15-degree inversion; (b) ankle-neutral, 30-degree inversion; (c) ankle-20-degree plantarflexion, 15-degree inversion; and (d) ankle-20-degree plantarflexion, 30-degree inversion.

RESULTS

Either in terms of acute or chronic effects, no significant differences were found after static stretching exercises for peroneal and tibialis anterior muscle reaction time, reaction duration, and muscle activity evaluated in four positions on the ankle inversion simulation platform (P > 0.05).

CONCLUSIONS

In light of these results, it is possible to state that the short duration of static stretching exercises can still be applied before sports activities.