Hip and knee muscle torque and its relationship with dynamic balance in chronic ankle instability, copers and controls

Blood flow restriction training improves the efficacy of routine intervention in patients with chronic ankle instability

As a new means of rehabilitation, blood flow restriction training (BFRT) is widely used in the field of musculoskeletal rehabilitation. To observe whether BFRT can improve the efficacy of routine rehabilitation intervention in patients with chronic ankle instability (CAI). Twenty-three patients with CAI were randomly divided into a routine rehabilitation group (RR Group) and a routine rehabilitation ​+ ​blood flow restriction training group (RR ​+ ​BFRT Group) according to the Cumberland Ankle Instability Tool (CAIT) score. The RR Group was treated with routine rehabilitation means for intervention, and the RR ​+ ​BFRT Group was treated with a tourniquet to restrict lower limb blood flow for rehabilitation training based on routine training. Before and after the intervention, the CAIT score on the affected side, standing time on one leg with eyes closed, comprehensive scores of the Y-balance test, and surface electromyography data of tibialis anterior (TA) and peroneus longus (PL) were collected to evaluate the recovery of the subjects. Patients were followed up 1 year after the intervention. After 4 weeks of intervention, the RR ​+ ​BFRT Group CAIT score was significantly higher than the RR Group (19.33 VS 16.73, p ​< ​0.05), the time of standing on one leg with eyes closed and the comprehensive score of Y-balance were improved, but there was no statistical difference between groups (p ​> ​0.05). RR ​+ ​BFRT Group increased the muscle activation of the TA with maximum exertion of the ankle dorsal extensor (p ​< ​0.05) and had no significant change in the muscle activation of the PL with maximum exertion of the ankle valgus (p ​> ​0.05). There was no significant difference in the incidence of resprains within 1 year between the groups (36.36% VS 16.67%, p ​> ​0.05). The incidence of ankle pain in the RR ​+ ​BFRT Group was lower than that in the RR Group (63.64% VS 9.09%, p ​< ​0.01). Therefore, four-weeks BFRT improves the effect of the routine intervention, and BFRT-related interventions are recommended for CAI patients with severe ankle muscle mass impairment or severe pain.

What is the influence of biomechanical variables on the Y balance test performance in recreational runners?

BACKGROUND

Asymmetries and poor Y balance test (YBT) performance are associated with an increased risk of injuries in athletes. The aim of this study was to investigate the association between YBT performance with biomechanical variables in runners.

METHODS

The runners underwent the YBT, followed by the assessment of center of pressure, plank position, muscle strength (MS) of hip flexors, extensors, abductors, and external rotators, knee extensors, ankle dorsiflexion range of motion (ROM), Q angle, forefoot alignment, and passive hip internal rotation. Associations between variables were examined using multiple linear regression models with the Bayesian Information Criterion.

RESULTS

122 cases were analyzed. The R2 values were 0.38; 0.05; 0.06; and 0.15 for the anterior, posteromedial, posterolateral and composite directions models, respectively. The anterior reach in the YBT was associated with ankle dorsiflexion ROM [Sβ 95%IC: 0.43 (0.32-0.55)], passive hip internal rotation [Sβ 95%IC: 0.35 (0.24-0.47)], MS of the hip extensors [Sβ 95%IC: 0.19 (0.07-0.31)] and forefoot alignment [Sβ 95%IC: 0.14 (-0.25-0.02)]. The posteromedial and posterolateral reach were associated with MS of the hip flexors [Sβ 95%IC: 0.23 (0.09-0.37) and 0.24 (0.11-0.38)], respectively. The composite score was associated with MS of the hip flexors [Sβ 95%IC: 0.31 (0.18-0.45)], ankle dorsiflexion ROM [Sβ 95%IC: 0.24 (0.10-0.37)] and Q angle [Sβ 95%IC: 0.18 (0.04-0.31)].

CONCLUSION

YBT performance in different directions demonstrated specific associations with key biomechanical factors.

Individuals With Chronic Ankle Instability Show Abnormalities in Maximal and Submaximal Isometric Strength of the Knee Extensor and Flexor Muscles

BACKGROUND

It has been shown that chronic ankle instability (CAI) leads to abnormalities in neuromuscular control of more proximal joints than the ankle. Although strength of the hip and the ankle muscles has been largely investigated providing concordant results, limited evidence with contrasting results has been reported regarding knee extensor and flexor muscles.

PURPOSE

To investigate maximal and submaximal isometric muscle strength in individuals with CAI.

STUDY DESIGN

Controlled laboratory study.

METHODS

Fifteen participants with unilateral CAI and 15 healthy matched controls were recruited. To quantify maximal strength, peak forces were recorded during a maximal isometric voluntary contraction of knee extensor and flexor muscles at 30° and 90° of knee flexion and normalized by the body weight of each participant. At both angles, submaximal isometric contractions at 20%, 50%, and 80% of the maximal voluntary isometric contraction were performed to analyze strength steadiness, in terms of coefficient of variation, and strength accuracy, in terms of absolute error. During all the assessments, knee extensor and flexor muscle activation was recorded by means of surface electromyography.

RESULTS

Knee flexor maximal isometric strength was significantly lower in the injured limb of individuals with CAI in comparison with healthy controls at both 30° (0.15 ± 0.05 vs 0.20 ± 0.05; P < .05) and 90° (0.14 ± 0.04 vs 0.18 ± 0.05; P < .05). Knee extensor and flexor steadiness was significantly lower (higher coefficient of variation) in both the injured and the noninjured limbs of individuals with CAI in comparison with healthy individuals at 90° and at 30° for knee flexor steadiness of the injured limb. Knee extensor and flexor accuracy was lower (higher absolute error) in both the injured and noninjured limbs of individuals with CAI in comparison with healthy individuals, mainly at 30°, while at 90° it was lower only in the injured limb. No differences between the 2 groups were found for maximal isometric strength of knee extensor muscles, as well as for muscle activations.

CONCLUSION

Individuals with CAI show abnormalities in maximal and submaximal isometric strength of knee flexor muscles, and submaximal strength of the knee extensor muscles. Further studies should deeply investigate mechanisms leading to these abnormalities.

CLINICAL RELEVANCE

Rehabilitation interventions should consider abnormalities of neuromuscular control affecting joints more proximal than the ankle in individuals with CAI.

REGISTRATION

NCT05273177 (ClinicalTrials.gov identifier).

Deficits in proprioception and strength may contribute to the impaired postural stability among individuals with functional ankle instability

Purpose: The correlations of postural stability with proprioception and strength may explain the recurrent sprains among individuals with functional ankle instability (FAI). This study aimed to compare anterior-posterior (AP) and medial-lateral (ML) postural stability, along with ankle proprioception and strength between individuals with and without FAI and investigated their correlations. Methods: Forty participants with FAI and another 40 without FAI were recruited. Their postural stability, represented by time to stabilization (TTS) in the AP (TTSAP) and ML (TTSML) directions, was calculated by the ground reaction force during jumping onto a force plate. Their ankle proprioception and strength during plantarflexion/dorsiflexion and inversion/eversion were measured using a proprioception device and a strength testing system, separately. Results: Individuals with FAI had longer TTSAP (p = 0.015) and TTSML (p = 0.006), larger ankle proprioception thresholds (p = 0.000-0.001), and less strength (p = 0.001-0.017) than those without FAI. Correlations between strength and TTSAP were detected among individuals with (ankle plantarflexion, r = -0.409, p = 0.009) and without FAI (ankle plantarflexion, r = -0.348, p = 0.028; ankle dorsiflexion, r = -0.473, p = 0.002). Correlations of proprioception (ankle inversion, r = 0.327, p = 0.040; ankle eversion, r = 0.354, p = 0.025) and strength (ankle eversion, r = -0.479, p = 0.002) with TTSML were detected among individuals without FAI but not among those with FAI. Conclusion: Individuals with FAI have worse postural stability and proprioception and less strength. Their proprioception and strength decreased to a point where they could not provide sufficient functional assistance to the ML postural stability. Improvements in proprioception and strength may be keys to prevent recurrent ankle sprains among individuals with FAI.

Using clinician-oriented and laboratory-oriented assessments to study dynamic stability of individuals with chronic ankle instability

To compare the dynamic stability of lower extremities between Copers and individuals with chronic ankle instability (CAI) using clinician-oriented assessments (Y-balance test, YBT) and laboratory-oriented assessments (time to stabilization, TTS). 90 participants (Copers, 45; CAIs, 45) were recruited and measured by YBT and TTS to evaluate dynamic stability. The difference of dynamic stability between Copers and CAIs was examined using a two-factor MANOVA. Only for females in anterior direction, YBT scores for the AS side of Copers were significantly higher than that of CAIs. For males, the TTS of CAIs was significantly shorter than that of Copers in the anterior, lateral, and medial direction separately. For females, the TTS of CAIs is also significantly shorter than that of Copers in the anterior, lateral, and medial direction separately. There are opposite results when evaluating the dynamic stability difference between Copers and CAIs using YBT and TTS.

Balance, strength and physical activity after ankle sprain: Comparison between children with chronic ankle instability and copers

OBJECTIVE

The aim of this study was to compare muscle strength, balance, and physical activity between children with chronic ankle instability and copers.

DESIGN

Cross-sectional study.

SETTING

Pediatric Physical Therapy laboratory.

PARTICIPANTS

Children aged between 7 and 12 years old from regular schools who had a history of unilateral ankle sprain.

MAIN OUTCOME MEASURES

Lower extremity strength, Static and dynamic standing balance, and Level of physical activity.

RESULTS

Fifteen children with chronic ankle instability and 15 copers were recruited. Demographic data showed no differences between group except for sex and the Cumberland Ankle Instability Tool-Youth (CAITY) score. Children with CAI had a significantly lower score during the standing long jump test (p < 0.05), poorer performance of single leg stance test (p < 0.001) and Y-Balance test in the anterior, posteromedial, and posterolateral directions (p < 0.05) when compared to copers. Total METs per week was significantly higher in the copers (p < 0.05).

CONCLUSION

Children with chronic ankle instability exhibited weaker lower limb strength, poorer static and dynamic standing balance, and participate in less physical activity compared to those in a coper group which may have future negative health consequences. Knowledge about the differences between the two groups may provide guidance for physical educators and physical therapists. (200 words).

Protocol for a randomised feasibility trial comparing a combined program of education and exercise versus general advice for ankle osteoarthritis

BACKGROUND

Ankle osteoarthritis (OA) is a serious problem with high associated pain and disability. While education and exercise are recommended for the initial management of OA, this has not been investigated in ankle OA. The primary aim of this study is to establish the feasibility of running a full-scale randomised controlled trial (RCT) investigating a combined education and exercise program compared to a general advice program for people with ankle OA. The secondary aims are to collect preliminary data which will inform sample size calculations, and understand the perspectives of people with ankle OA on their participation in the trial.

METHODS

Thirty individuals aged 35 years or older with symptomatic radiographic ankle OA will be recruited from the community and randomised to receive either a combined education and exercise program or a general advice program, both of which will be delivered by a physiotherapist in a group setting. Primary outcomes of feasibility include responses to study advertisements, number of eligible participants, recruitment rate, adherence with the intervention, fidelity of the intervention, adverse events, drop-out rate, and credibility and expectancy of the intervention. Secondary participant-reported outcomes will include global rating of change, patient acceptable symptom state, severity of ankle pain and stiffness, self-reported function, quality of life, satisfaction with treatment, and use of co-interventions. Follow up will be at 8 weeks and 3 months. Physical measures of 40 m walking speed, timed stairs descent, heel raise endurance and ankle dorsiflexion range of motion will be collected at baseline and 8 weeks. Primary feasibility outcomes will be reported descriptively, and estimates of the variability of secondary participant-reported and physical outcomes will be calculated. Semi-structured interviews will be conducted with participants to understand perspectives about the intervention and participation in the trial, with data analyzed thematically.

DISCUSSION

Study findings will establish the feasibility of running a full-scale RCT to investigate a combined education and exercise program compared to a general advice program for people with ankle OA. This study is a necessary first step to advance the international research agenda of evaluating the efficacy of exercise in the management of ankle OA.

TRIAL REGISTRATION

ACTRN12623000017628. Registered 10 January 2023, https://www.anzctr.org.au/ACTRN12623000017628.aspx .

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

BACKGROUND

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

METHODS

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

FINDINGS

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

INTERPRETATIONS

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

Analysis of technical characteristics of typical lower limb balance movements in Tai Chi: a cross-sectional study based on AnyBody bone muscle modeling

BACKGROUND

Tai Chi is an excellent traditional Chinese physical fitness exercise, and its unique balancing movements are very important for improving human balance. In this study, the two most representative Tai Chi balance movements, "knee lift balance" and "leg stirrup balance", were selected to establish the lower limb bone muscle model of Tai Chi balance movements by using computer simulation modeling technology, aiming to analyze the characteristics of the lower limb movement mechanisms of typical balance movements, to provide a quantitative theoretical basis for improving the scientific level of Tai Chi.

METHOD

A total of 16 subjects were recruited for this study. the BTS three-dimensional motion capture system and three-dimensional force platform were used for motion data acquisition, the physiological electromyographic signals were collected using BTS surface electromyography, and the lower limb bone muscle model of Tai Chi balance movements was established by AnyBody human simulation.

RESULT

In the knee lift balancing movement, the balance leg hip abduction/adduction angle, hip flexion/extension moment, and the strength of the rectus femoris muscle, biceps femoris short capitis, and iliacus muscle of the amateur group was significantly smaller than that of the professional group (P < 0.01). In the leg stirrup balance movement, the knee flexion/extension angle of the balancing leg in the amateur group was significantly greater than that in the professional group (P < 0.01), and the hip flexion/extension angle, hip inversion/abduction angle, knee flexion/extension moment, hip flexion/extension moment, the strength iliacus, gluteus maximus, and obturator internus were significantly smaller than those in the professional group (P < 0.01). The integral EMG of the biceps femoris of the support leg in the amateur group was significantly smaller than that of the professional group (P < 0.01). The integral EMG of the lateral femoral muscle of the balance leg was significantly smaller than that of the professional group (P < 0.01).

CONCLUSION

In this study, we found that the balancing leg of the balancing movement has a larger hip joint angle, the stirrup balancing knee joint angle is smaller, and the hip and knee joint moments are larger. This is related to joint activity and muscle activation, and amateurs should pay attention to increasing the range of motion of the hip joint and decreasing the range of motion of the knee joint when practicing to better stimulate exercise of the lower limb joints. In addition, the practice of balancing movements should strengthen the iliacus muscle, which plays an important role in maintaining the stable balance of the lower limbs, and strengthen the knee flexor and extensor muscles and hip adductor/abductor muscles of the balancing leg, thus promoting the stability of the balancing leg movements.

Acute effects of kinesiology tape on dynamic balance control in chronic ankle instability: An exploratory study

OBJECTIVE

To investigate the acute effect of the four-strip kinesiology taping (KT) technique on dynamic balance control in the Y Balance Test (YBT), and to explore the relationship between the YBT and Cumberland Ankle Instability Tool (CAIT) scores in individuals with and without chronic ankle instability (CAI).

METHODS

16 CAI and 16 non-CAI participants were involved. Two groups completed the YBT in the no-tape barefoot and the KT condition at random. The CAIT was completed on the first day. Bonferroni test was used to analyze YBT scores in three directions for post hoc analysis. Spearman's correlation was used to analyze the relationship between YBT scores in the no-tape barefoot condition and CAIT scores.

RESULTS

This KT application significantly improved YBT performance. The YBT scores in the anterior direction (YBT-A), posteromedial direction (YBT-PM), and posterolateral direction (YBT-PL) for the CAI group were significantly improved after taping. However, in the non-CAI group, only YBT-PM score was significantly improved after taping. Three YBT scores were all moderately correlated with the CAIT score.

CONCLUSION

This KT technique can immediately improve dynamic balance in CAI patients. Dynamic balance performance was moderately related to the degree of self-perceived instability in individuals with and without CAI.

Thirty Minutes Identified as the Threshold for Development of Pain in Low Back and Feet Regions, and Predictors of Intensity of Pain during 1-h Laboratory-Based Standing in Office Workers

This study with 40 office workers investigated (a) the effect of time spent standing on low- back and lower limb pain during a 1-h laboratory-based task; (b) the standing time after which a significant increase in pain is likely; and (c) the individual, physical and psychosocial factors that predict pain. The primary outcome was bodily location of pain and pain intensity on a 100-mm Visual Analogue Scale recorded at baseline and every 15 min. Physical measures included trunk and hip motor control and endurance. Self-report history of pain, physical activity, psychosocial job characteristics, pain catastrophizing and general health status were collected. Univariate analysis and regression models were included. The prevalence of low-back pain increased from 15% to 40% after 30 min while feet pain increased to 25% from 0 at baseline. The intensity of low-back and lower limb pain also increased over time. A thirty-minute interval was identified as the threshold for the development and increase in low-back and feet pain. Modifiable factors were associated with low-back pain intensity—lower hip abductor muscle endurance and poorer physical health, and with feet symptoms—greater body mass index and less core stability.

Hip Flexibility and Dynamic Balance Ability in Soccer Players with Functional Ankle Instability

The prevention of recurrent ankle sprain and functional ankle instability in soccer players is essential. This study clarified hip joint mobility and dynamic balance ability in soccer players with functional ankle instability. This case–control study included 17 male college soccer players. All participants were assessed using the Cumberland Ankle Instability Tool and were divided into chronic ankle instability (CAI) and non-CAI groups for each of their dominant and nondominant legs. Bilateral passive hip range of motion (ROM) was assessed and the modified Star Excursion Balance Test (mSEBT) was measured for each leg. In the dominant leg, the reach in the posterolateral direction in the CAI group was significantly less than that in the non-CAI group. Hip internal rotation angles in the dominant leg in the CAI group were greater than those in the non-CAI group; however, no significant correlations with the three directions of mSEBT were observed. In the nondominant leg, mSEBT and hip ROMs did not show any significant differences between groups. The dominant leg in soccer players with CAI had poor dynamic balance ability while reaching posterolaterally. However, acquiring hip flexibility may not be necessary to improve the dynamic balance ability. These findings may help develop future research.

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.

Hip and knee muscle torque is not impaired in the first three months of a first-time lateral ankle sprain

OBJECTIVES

The primary objective was to compare hip and knee isometric muscle strength between individuals with a first-time acute lateral ankle sprain and controls. A secondary objective was to investigate hip and knee isometric muscle strength three months post-injury.

DESIGN

Cross-sectional and prospective follow-up components.

SETTING

Laboratory environment.

PARTICIPANTS

Forty-two participants (21 acute lateral ankle sprain and 21 controls) matched for age, sex, physical activity and leg dominance participated.

MAIN OUTCOME MEASURES

Hip and knee isometric muscle torque was assessed using a rigidly fixated hand-held dynamometer. Testing in acute lateral ankle sprain participants was performed within four weeks of injury and three months post-injury. Controls were tested at one timepoint.

RESULTS

There were no differences in hip or knee isometric muscle torque between acute lateral ankle sprain and control participants (mean differences <0.08). Hip and knee isometric muscle torque in acute ankle sprain participants did not differ between baseline and three months post-injury testing (mean difference <0.06).

CONCLUSIONS

Proximal lower limb isometric strength is not impaired within the first three months of sustaining a first-time lateral ankle sprain injury. This implies that hip and knee isometric strength deficits in individuals with CAI may occur at some later stage.