CONTEXT:Chronic ankle instability (CAI) patients exhibit altered movement patterns during jump landing/cutting movements. Persistent pain is one of the residual symptoms that may affect movements. Calculating joint energetics affected by chronic pain offers a novel method to understand how chronic pain influences energetics of lower extremity joints in CAI patients. OBJECTIVE:To identify the effects of chronic pain on lower extremity energy dissipation and generation during jump landing and cutting in patients with CAI. DESIGN:Cross-sectional study. SETTING:Laboratory. PATIENTS OR OTHER PARTICIPANTS:Fifteen CAI patients with higher pain (6 men and 9 women; age = 22.1 ± 2.1 years, height = 1.74 ± 0.09 m, mass = 71.3 ± 10.6 kg, pain = 66.9 ± 9.4), 15 patients with CAI and lower pain (6 men and 9 women; age = 22.3 ± 2.1 years, height = 1.74 ± 0.08 m, mass = 70.1 ± 10.7 kg, pain = 89.3 ± 2.6), and 15 healthy control individuals (6 men and 9 women; age = 21.3 ± 1.7 years, height = 1.73 ± 0.08 m, mass = 70 ± 10.3 kg, pain = 100 ± 0). MAIN OUTCOME MEASURE(S):Ground reaction force data were collected during 5 trials of maximal jump landing/cutting tasks. Joint power was defined as the product of angular velocity and joint moment. Energy dissipation and generation by the ankle, knee, and hip joints were calculated by integrating regions of the joint power curve. RESULTS:CAI patients with higher pain displayed less ankle energy dissipation (P = .013 and P = .018) and generation in the ankle (P = .002 and P = .028) than CAI patients with lower pain and healthy control individuals during the jump landing/cutting phase. CAI patients with higher pain showed more hip energy generation than CAI patients with lower pain (P = .038) and healthy control individuals (P = .013) during the cutting phase. CONCLUSIONS:CAI patients with higher pain changed both energy dissipation and generation in the lower extremities, reducing the burden of the ankle joint during jump landing/cutting and having a hip-dominant compensatory strategy during the cutting phase. Our results suggest that chronic pain could be one of the factors that affect motor strategies in the CAI population.

Binders are essential electrode materials used to bond active and conductive materials together and fix them to the current collector. Therefore, binders are essential in ensuring mechanical stability and maintaining the microstructure to ensure a smooth flow of ions and electrons. In flexible electrodes, binders have the additional role of enhancing flexibility. Ultraflexible electrodes can be fabricated by exploiting the thermoplastic properties of the poly(vinylidene fluoride) (PVDF) binder using thermally induced phase separation (TIPS). Because binders are insulating materials, excess amounts can affect the specific capacity; therefore, their amount should be determined by considering the interplay between flexibility and capacity. In this study, four TIPS-based electrodes having 10, 20, 30, and 40 wt % PVDF were investigated to understand the effect of binder amount on the electrode properties. The electrodes with 10 and 20 wt % PVDF attained a high capacity (180 mAh g-1), significantly outperforming those containing 30 and 40 wt %. Notably, the electrodes containing less PVDF (<= 20 wt %) had considerably higher porosity than those containing larger amounts, suggesting that the outstanding capacity is attributed to high porosity, which enhances ionic conductivity. The poor capacity of the higher PVDF electrodes (>= 30 wt %) is associated with high ionic and electronic resistances resulting from low porosity and polymer adsorption that blocks the electron conductive network. Conversely, the electrodes containing larger amounts of PVDF achieved a higher tensile strain and greater flexibility. Considering the trade-off between electrochemical and mechanical properties, the preparation of electrodes with smaller quantities of PVDF is suggested. This study provides a systematic approach to understanding the effect of binder on flexible electrodes and can be extended to other devices where binder is applied, including energy storage and biomedical devices.

BackgroundAlthough individuals with anterior cruciate ligament reconstruction (ACLR) are at high risk for posttraumatic osteoarthritis, mechanisms underlying the relationship between running and knee cartilage health remain unclear.ObjectiveWe aimed to investigate how 30 min of running influences femoral cartilage thickness and composition and their relationships with running biomechanics in patients with ACLR and controls.MethodsTwenty patients with ACLR (time post-ACLR: 14.6 +/- 6.1 months) and 20 matched controls participated in the study. A running session required both groups to run for 30 min at a self-selected speed. Before and after running, we measured femoral cartilage thickness via ultrasound imaging. A MRI session consisted of T2 mapping.ResultsThe ACLR group showed longer T2 relaxation times in the medial femoral condyle at resting compared with the control group (central: 51.2 +/- 16.6 vs. 34.9 +/- 13.2 ms, p = 0.006; posterior: 50.2 +/- 10.1 vs. 39.8 +/- 7.4 ms, p = 0.006). Following the run, the ACLR group showed greater deformation in the medial femoral cartilage than the control group (0.03 +/- 0.01 vs. 0.01 +/- 0.01 cm, p = 0.001). Additionally, the ACLR group showed significant negative correlations between resting T2 relaxation time in the medial femoral condyle and vertical impulse (standardized regression coefficients = -0.99 and p = 0.004) during running.ConclusionsOur findings suggest that those who are between 6 and 24 months post-ACLR have degraded cartilage composition and their cartilage deforms more due to running vGRF.

Patients with chronic ankle instability (CAI) consistently display postural control alterations, which may result from sensorimotor dysfunction. This study aimed to compare muscle activity in the lower extremity and postural control among individuals with CAI, copers and uninjured controls during a static balance test. A total of 57 physically active participants were categorized into three groups (CAI, copers and controls) and performed a single-leg balance test with two visual conditions: eyes open and eyes closed. Muscle activity in six lower extremity muscles and center of pressure (CoP) variables were recorded and analyzed. Patients with CAI exhibited greater muscle activity in the medial gastrocnemius and gluteus maximus compared to controls or copers, regardless of the visual condition. Copers displayed increased gluteus medius activity compared to controls. Additionally, all groups demonstrated increased muscle activity and CoP variables when visual feedback was disrupted. These findings suggest that patients with CAI may have less effective recruitment of motor units during static balance. On the other hand, greater muscle activity in the gluteus medius in copers may represent a coping mechanism to avoid further ankle injuries. Further research on muscle activity during dynamic postural control is warranted to explore sensorimotor alterations in patients with CAI.

In recent years, technology of soft robotics has emerged as an important issue for the robot industry. Compared to conventional industrial metallic robots in controlled environments, soft robots are highly expandable in responding to non-standardized environments. Due to these characteristics, it is expected to be used not only in daily life, but also in specific applications such as treatment of disease and disaster relief. The development of a structure that is free to deformation with energy source is also essential to improve the technology. Among several energy sources, Lithium ion batteries (LIBs) are the prime choices for these applications due to light weight, high energy density and long cycle life. The integration of flexible structure and LIBs is very important to reduce the waste of space and weight of soft robots for versatility and portability. However, there are many difficulties due to the absence of batteries with high reliability under deformation. LIBs usually have little flexibility due to the high stack cells and stiff nature of cell components. It is required to have a new design of LIBs. Geometrically designed structures incorporating bioinspiration are promising solutions for integrating components of soft robots. In this study, we propose a novel geometric structure for stretchable devices, created by folding well-defined two-dimensional patterns with cutouts to produce an extremely stretchable structure with superior reliability and bi-axial deformability. The structure is designed to mimic the hinge of a snakeskin so that its unit cells do not interfere with each mutual movement enabling stable deformations without mechanical damage. In addition, to maximize areal density and stretchability, the optimal shape of unit is determined. The unit-based geometric structure is applied to a stretchable Li-ion battery and constructed of hexagonal pouch cells and parallelogram interconnections. In situ electrochemical characterization confirms that the performance of the battery is maintained under dynamic deformation with a stretching ratio of 90% and a 10-mm-radius bending curvature, guaranteeing a long-lasting cycle life. To confirm the mechanical reliability of the scale battery, the strain distribution at the flexible hinge is obtained by FEA(Finite element analysis). The strain is mainly localized in the folding parts of the interconnection, and it is found that the unit cell experiences on deformation during the unfolding process. This is the main reason that the electrochemical performance is maintained during the mechanical deformation of the scale battery. Finally, the geometrically designed structure-based battery is applied to movable robots, crawling and slithering, with dynamic bi-axial deformations and can be pivotal role in the development of flexible electronics including human-friendly wearable electronics and soft robots.

Thick, flexible electrodes are essential to simultaneously achieving flexibility and high energy density; however, mechanical failure and the sluggish movement of ions and electrons both restrict their application. Here, a thick electrode reinforced by a stainless-steel (SS) fiber three-dimensional (3D) current collector is proposed that simultaneously attains unprecedented flexibility and a high energy density. This ultra-flexible electrode is prepared by a thermally induced phase separation process. Its meso/macroporosity enhances ionic conductivity, and the 3D fiber reinforcement enhances interfacial adhesion, flexural durability, and electrical conductivity. Owing to these advantages, the fiber-reinforced electrode has a minimum bending radius of 3 mm owing to its high yield strain (13

OBJECTIVE:To identify the effects of chronic pain levels on static and dynamic postural (DP) control in individuals with chronic ankle instability (CAI). DESIGN:Cross-sectional study. SETTING:Controlled laboratory. PARTICIPANTS:Sixty participants were divided into the following 3 groups: 20 high pain individuals with CAI (high pain), 20 low pain individuals with CAI (low pain), and 20 healthy controls (control). INDEPENDENT VARIABLES:Groups (CAI with high pain, CAI with low pain, and control) and visual conditions (eyes open and closed) for single-leg stance. MAIN OUTCOME MEASURES:Participants performed single-leg stance with eyes open and closed, the star excursion balance test, and single-leg hop to stabilization. RESULTS:The high pain group experienced worse self-reported outcomes, including Foot and Ankle Ability Measure activities of daily living and sports, than the low pain and control groups. Regardless of visual condition, both the high and low pain groups exhibited decreased static postural control in mediolateral (ML) compared with the control group. Specifically, the high pain group showed decreased static postural control in ML under closed eyes compared with the low pain and the control groups. The high pain group showed less reach distance than the control group and increased DP control in vertical and overall DP stability index compared with the low and control groups. CONCLUSIONS:Chronic pain can significantly affect both static and DP control in individuals with CAI. Therefore, clinicians should consider chronic pain as one of the factors affecting postural control in individuals with CAI.

It remains unclear how unexpected perturbations during single-leg landings affect lower extremity kinematics and muscle activations in patients with chronic ankle instability (CAI). The purpose of this study was to identify the differences in lower extremity movement patterns among CAI subjects, copers, and healthy controls. Sixty-six people including 22 CAI subjects, 22 copers, and 22 healthy controls volunteered to participate in the study. Lower extremity joint kinematics and EMG activations from 200-ms pre to 200-ms post the initial contact during unexpected tilted landings were measured. Functional data analysis was used to evaluate between-group differences for outcome measures. Relative to copers and healthy controls, CAI subjects showed more inversion from 40-ms to 200-ms after initial contact. Relative to healthy controls, CAI subjects and copers showed more dorsiflexion. Relative to healthy controls, CAI subjects and copers showed more muscle activation in tibialis anterior and peroneus longus, respectively. In conclusion, CAI subjects demonstrated greater inversion angles and muscle activation before initial contact compared to LAS copers and healthy controls. This suggests that CAI subjects and copers prepare for their landing with protective movements, but the prepared movements shown by CAI subjects may be insufficient to reduce risk of recurrent injury.

BACKGROUND:Postural control measured during single-leg stance and single-leg hop stabilization has been used to estimate sensorimotor function in CAI individuals and copers. To date, studies have not used postural control tasks as a way of measuring responses to sudden changes in sensory information after simulated ankle inversion landings. RESEARCH QUESTION:A cross-sectional study was performed to identify any differences in static and dynamic postural control before and after simulated ankle inversion landings among individuals with chronic ankle instability (CAI), copers, and healthy controls. METHODS:Nineteen CAI individuals, 19 copers, and 19 controls participated in this study. Participants performed 3 static and dynamic balance tasks before and after simulated ankle inversion landings onto a 25° tilted platform from a height of 30 cm. The main outcome measures were the center of pressure (COP) velocity and range from the single-leg stance, as well as the dynamic postural stability index from the single-leg hop stabilization. The Wilcoxon signed-rank test was used to compare posttest and pretest differences in static and dynamic postural control between groups. RESULTS:In the static postural control measures, the CAI group had a higher difference in COP velocity and COP range in the frontal plane (p < 0.05 and p < 0.05, respectively) than the coper group. In the dynamic postural control measures, the CAI group demonstrated a higher difference in the vertical stability index (p < 0.05) than the healthy control group. SIGNIFICANCE:CAI individuals have persistent worse postural control after somatosensory modulation due to their inability to adapt to sudden somatosensory modulation. Relative to CAI individuals, copers may have different abilities not only the integration of somatosensory input about ankle inversion modulation, but also the adaptation of the entire motor control system, preventing recurrent ankle sprains after an initial LAS. Therefore, somatosensory modulation may be the indicator of understanding CAI and coper.

Nickel (Ni) is an essential resource in many industries. However, as the industrial use of Ni increases, its impact as an environmental pollutant has also increased. Accordingly, effective Ni treatment processes are required. In this study, hybrid capacitive deionization (HCDI) with an Ag-coated activated carbon (AC) electrode was proposed as a Ni treatment. The deionization capacity of the HCDI system with Ag coating was 66% higher than that of the membrane capacitive deionization system. In addition, as the applied potential increased from 0.5 V to 1.1 V, the deionization capacity also increased from 10 mg/g to 18 mg/g, although the charge efficiency decreased from 84.6% to 77.2%. However, when the applied potential was 0.9 V or more, the pH of the effluent exceeded the drinking water range, which appeared to be caused by the electron transfer reaction of Ni ions under a high applied potential (0.9 V or more). In terms of energy consumption, HCDI with Ag-coated electrodes achieved 0.24 Wh/g-NiCl2 as a minimum value. The results of this study demonstrate the potential of capacitive deionization (CDI) for Ni treatment.

CONTEXT:Participants with chronic ankle instability (CAI) frequently display altered movement patterns during functional movements. However, it remains unclear how these altered joint kinematics during jump landing negatively affect ankle joint health in the CAI population. Calculating joint energetics may offer an important method to estimate the magnitude of lower extremity joint loading during functional movements in participants with CAI. OBJECTIVE:To determine differences in energy dissipation and generation by the lower extremity during maximal jump landing and cutting among groups with CAI, copers, and controls. DESIGN:Cross-sectional study. SETTING:Laboratory. PATIENTS OR OTHER PARTICIPANTS:Forty-four participants with CAI, 44 copers, and 44 controls. MAIN OUTCOME MEASURES(S):Kinematics and kinetics of the lower extremity and ground reaction force data were collected during a maximal jump-landing and cutting task. The product of angular velocity in the sagittal plane and joint moment data represented joint power. Energy dissipation and generation by the ankle, knee, and hip joints were calculated by integrating regions of the joint power curve. RESULTS:Participants with CAI displayed reduced ankle energy dissipation (35.9% ± 10.1%) and generation (31.6% ± 12.8%; P < .01) compared with copers (dissipation = 43.6% ± 11.1%; generation = 40.4% ± 12.0%) and controls (dissipation = 41.3% ± 11.1%; generation = 39.6% ± 12.0%) during maximal jump landing and cutting. Participants with CAI also displayed greater energy dissipation at the knee (45.1% ± 9.1%) than copers (39.7% ± 9.5%) during the loading phase and greater energy generation at the hip than controls (36.6% ± 16.8% versus 28.3% ± 12.8%) during the cutting phase. However, copers displayed no differences in joint energetics compared with controls. CONCLUSIONS:Participants with CAI displayed differences in both energy dissipation and generation by the lower extremity during maximal jump landing and cutting. However, copers did not show altered joint energetics, which may represent a coping mechanism to avoid further injuries.

Chronic ankle instability (CAI) patients experience repeated bouts of trauma to the ankle, resulting in a fear of movement called kinesiophobia. Little is known about the cumulative effect that kinesiophobia and CAI can have on neuromuscular control during demanding movements. PURPOSE: To examine the effect of kinesiophobia on lower extremity muscle activation patterns during jump landing/cutting in patients with CAI (CAI-Fear) relative to other CAI patients (CAI-No) and controls. METHODS: 50 CAI patients were separated into 2 subgroups based on their responses to the Tampa Scale of Kinesiophobia (TSK-11): CAI-Fear (N: 25, TSK-11: 42.0 ± 3.6, 71.8 ± 14.4 kg, 1.76 ± 0.10 m) and CAI-No (N: 25, TSK-11: 33.0 ± 3.2, 71.5 ± 12.1 kg, 1.74 ± 0.1 m) with a control group (N: 20, 75.7 ± 15.8 kg, 1.74 ± 0.07 m). Subjects performed 5 jump landing/cutting trials. EMG data of tibialis anterior (TA), peroneus longus (PL), medial gastrocnemius (MG), vastus lateralis (VL), gluteus medius (Gmed), and gluteus maximus (Gmax) were collected from initial contact to toe-off. EMG data were smoothed using a root mean square algorithm (125 ms window) and normalized to the smoothed reference EMG data. Functional analyses of variance and 95% confidence intervals were used to detect differences. RESULTS: Figure 1 shows decreased activation of TA, PL, VL, and Gmax as well as increased activation of Gmed and MG of the CAI-Fear group when compared to CAI-No. Compared to the control, the CAI-Fear group demonstrated decreased activation of the PL, MG, VL, and Gmax and increased activation of Gmed. CAI-No patients demonstrated decreased activation of TA, PL, MG, Gmed, and Gmax when compared to the control. CONCLUSIONS: Kinesiophobia leads to altered lower extremity muscle activation during a jump landing/cutting task. The CAI-No and control groups demonstrated the ability to dynamically stabilize the ankle through increased muscle activation of lower limb muscles, while CAI-Fear subjects did not.

OBJECTIVES The purpose of this study was to report changes in pain perception and the transcutaneous electrical nerve stimulation (TENS) pulse amplitude, and progressions in aerobic and resistance exercise at each session during a ten-session rehabilitation programme for patients with anterior knee pain.METHODS Eleven patients with anterior knee pain (4 females and 7 males: 20.8 ± 2.8 years, 169.7 ± 8.1 cm, 72.9 ± 25.0 kg, painful duration: 51.3 ± 42.0 months, Kujala anterior knee pain scale: 73.4 out of 100) participated in the rehabilitation programme. Each session of rehabilitation consisted of a 30-min simultaneous application of TENS and focal knee joint cooling, followed by a 30-min of therapeutic exercises (aerobic, flexibility, and strengthening exercise). Pain perception (using a 10-cm visual analogue scale) before and after each session, transcutaneous electrical nerve stimulation pulse amplitude (mA), treadmill jogging speed (km/h), and external load during resistance exercises (knee extensions, squats, and lunges in kg/kg) at each session were recorded.RESULTS Overall pain perception was reduced (49%, p=0.0008) and the TENS pulse amplitude was increased (20%, p=0.002) at the fourth session. The jogging speed increased at the third (9%, p=0.008), fifth (7%, p=0.03), and ninth (9%, p=0.0007) session. External loads in resistance exercises were increased every session that the total improvement was 98% in lunges (p<0.0001), 95% in knee extensions (p<0.007), 105% in squats (p<0.0001).CONCLUSIONS The observed changes and progressions could be used as general guidelines for the establishment and implementation of a short-term conservative treatment of anterior knee pain.

Chronic ankle instability (CAI) patients have altered force steadiness and accuracy and increased visual reliance. However, little is known about the effect of using stroboscopic glasses on force steadiness and accuracy during rehabilitation in CAI patients. PURPOSE: To identify the effects of stroboscopic glasses on submaximal force steadiness and accuracy of ankle evertors, invertors, and hip abductors and visual reliance following 4 weeks of rehabilitation in CAI patients. METHODS: 50 CAI patients were equally assigned to 2 groups. The strobe group wore stroboscopic glasses during rehabilitation, while the control group did not. Before and after rehabilitation, force steadiness and accuracy were measured in 10% and 20% of maximum voluntary isometric contraction (MVIC) with eyes open (EO) and strobe vision (SV) conditions. Romberg ratios were calculated as SV/EO to identify visual reliance. Two-way ANOVA was used to identify differences in force steadiness and accuracy between groups and visual conditions. A mixed model ANOVA was used to identify differences in the Romberg ratio between groups and times. RESULTS: For force accuracy, the strobe group showed a greater pre-post difference in 10% of evertor MVIC than the control group when in the SV (0.36vs.0.23, p = 0.03) and showed a greater pre-post difference in 10% of evertor MVIC in the EO than in the SV (0.18vs.0.36, p = 0.04). In the force accuracy, CAI patients showed a lower Romberg ratio in 10% of evertor MVIC regardless of group after rehabilitation (1.48vs.1.13, p = 0.006), and the strobe group showed a lower Romberg ratio in 10% of evertors after rehabilitation (1.56vs.1.00, p = 0.03). CONCLUSIONS: CAI patients who wore stroboscopic glasses demonstrated increased force accuracy and had reduced visual reliance following 4 weeks of rehabilitation. In conclusion, stroboscopic glasses may offer clinicians a new means to reduce visual reliance and reweight sensory function during rehabilitation in CAI patients. - Table 1. Force Accuracy Condition (mean ± SD) Romberg ratio(mean ± SD) Variables Time Group EO SV SV/EO Evertors 10%*,**,†,‡ Pre Strobe 0.41 ± 0.20 0.60 ± 0.19 1.56 ± 1.03 Control 0.41 ± 0.22 0.54 ± 0.40 1.39 ± 1.44 Post Strobe 0.23 ± 0.12 0.24 ± 0.39 1.00 ± 0.29 Control 0.28 ± 0.17 0.31 ± 0.14 1.26 ± 0.71 20% Pre Strobe 0.63 ± 0.42 0.72 ± 0.43 1.41 ± 0.78 Control 0.73 ± 0.55 0.80 ± 0.67 1.07 ± 0.48 Post Strobe 0.42 ± 0.30 0.55 ± 0.55 1.53 ± 1.47 Control 0.47 ± 0.43 0.50 ± 0.35 1.13 ± 0.43 Invertors 10% Pre Strobe 0.68 ± 0.56 0.69 ± 0.57 1.18 ± 0.62 Control 0.76 ± 0.85 0.81 ± 0.85 1.39 ± 1.74 Post Strobe 0.29 ± 0.22 0.30 ± 0.21 1.04 ± 0.25 Control 0.33 ± 0.39 0.40 ± 0.50 1.05 ± 0.50 20% Pre Strobe 0.84 ± 0.57 0.90 ± 0.60 1.10 ± 0.33 Control 1.01 ± 0.95 1.06 ± 0.91 1.20 ± 0.63 Post Strobe 0.40 ± 0.20 0.42 ± 0.20 1.15 ± 0.34 Control 0.55 ± 0.67 0.54 ± 0.72 0.99 ± 0.22 Hip Abductors 10% Pre Strobe 4.68 ± 1.60 4.73 ± 1.33 1.06 ± 0.30 Control 5.19 ± 2.63 5.26 ± 2.25 1.11 ± 0.50 Post Strobe 5.86 ± 2.58 5.36 ± 2.57 0.90 ± 0.11 Control 6.11 ± 1.83 5.42 ± 1.59 0.90 ± 0.15 20% Pre Strobe 9.87 ± 2.89 12.75 ± 2.83 0.96 ± 0.08 Control 11.00 ± 4.36 10.64 ± 4.32 0.97 ± 0.08 Post Strobe 11.48 ± 4.52 11.19 ± 4.42 0.98 ± 0.07 Control 12.91 ± 3.28 12.39 ± 3.20 0.96 ± 0.08

Poor postural control is linked with chronic ankle instability (CAI). Although intrinsic foot muscle strength likely has an influence on postural control, little is known about the relationship between intrinsic foot muscle strength and postural control in CAI patients. PURPOSE: To compare intrinsic foot muscle strength and static balance among CAI patients, copers, and controls. A secondary purpose was to examine the relationship between intrinsic foot muscle strength and static balance in CAI patients, copers, and controls. METHODS: Participants were categorized according to the Foot and Ankle Ability Measure (FAAM) and Ankle Instability Index (AII) questionnaires. Twenty CAI patients (10 M, 10 F,1.74 ± 0.1 m, 69.1 ± 10.2 kg), 20 copers (10 M, 10 F, 1.76 ± 0.1 m, 70.9 ± 11.1 kg), and 20 controls (10 M, 10 F, 1.74 ± 0.1 m, 66.0 ± 10.7 kg) participated. Participants performed three different intrinsic foot muscle strength tests: (1) Doming strength, (2) Great toe strength, and (3) Lateral toe strength. All strength measures were normalized to each participant's body mass. After, each participant performed 3 trials of a single-leg balance test for 10 seconds. One-way ANOVAs were used for group comparisons. Simple-linear regressions examined the relationship between intrinsic foot muscle strength and static balance variables. RESULTS: There were no differences in intrinsic foot muscle strength and static balance among the three groups. From the linear regression, in the CAI group, there were negative correlations between the great toe strength and static balance variables (e.g., Average center of pressure velocities of X and Y). In the control group, there were positive correlations between the doming strength and static balance variables (e.g., Average center of pressure velocities of X and Y). CONCLUSION: From the data collection it is important that reduced intrinsic foot muscle strength after lateral ankle sprains may negatively affect postural control in patients with CAI. In other words, great toe muscle strength may be an important aspect to restore postural control for the CAI population to prevent further injuries. Along with restoring peroneal muscle strength, clinicians should focus on restoring intrinsic foot muscle strength to restore or develop postural control in patients with CAI.

Chronic ankle instability (CAI) patients consistently display altered movement patterns during functional movements, such as walking, running, and maximal jump-landing/cutting. Although these alterations could direct clinicians to develop appropriate rehabilitation programs for CAI patients, evaluating CAI patients for the quality of movement and sensorimotor alterations using a traditional 3D motion capture system is not easily accessible in clinical settings. PURPOSE: To examine altered movement patterns in CAI patients during maximal jump-landing/cutting using inertial measurement unit (IMUs) devices. METHODS: Twenty-one CAI patients (M = 11, F = 10; 174 ± 8 cm, 66.5 ± 8.9 kg 85.5 ± 6.1% FAAM-ADL, 68.7 ± 13.6% FAAM-Sports, 6.4 ± 1.4 AII) and 21 controls (M = 11, F = 10; 174 ± 8 cm, 66.3 ± 9.1 kg, 100% FAAM-ADL, 100% FAAM-Sports, 0 AII) participated. Participants completed 5 trials of a maximal jump-landing/cutting task. Lower-extremity kinematics of the ankle, knee and hip joints in the sagittal and frontal planes were collected from initial-contact (0%) to toe-off (100%) during a functional movement test. Functional ANOVAs were used to detect between-group differences (i.e., CAI and control). If 95% CIs did not cross zero, differences were significant. RESULTS: Figure 1 shows that CAI patients displayed less plantarflexion, dorsiflexion, inversion angles in the ankle joint relative to controls. In addition, CAI patients showed greater knee and hip flexion angles relative to controls. CONCLUSION: The IMUs were able to detect altered movement patterns in CAI patients during a maximal jump-landing/cutting task. Thus, IMUs can be effective assessment devices to examine altered movement patterns without relying on a traditional 3D motion capture system. Clinicians should consider utilizing IMUs to measure and evaluate movement patterns in the CAI population in clinical settings.

BACKGROUND:Patients with chronic ankle instability (CAI) often experience injury-related fear following ankle injuries, a condition known as kinesiophobia. Little research has investigated the impact of kinesiophobia in patients with CAI. RESEARCH QUESTION:How does kinesiophobia impact the static and dynamic balance of individuals with CAI? METHODS:Fifty patients with CAI were divided into 2 subgroups based on their responses to the Tampa Scale of Kinesiophobia: 25 with kinesiophobia (CAI-K) and 25 without kinesiophobia (CAI-N). These groups were compared to 20 control participants. All participants performed a single-leg balance test with eyes open (EO) and eyes closed (EC). They also performed the Y-balance test (YBT) with EO. Romberg ratios were calculated as EC/EO and used for statistical analysis. RESULTS:No differences in static balance with EO and EC were found among three groups. However, the CAI-K group displayed a higher Romberg ratio in the mediolateral direction during static balance than both CAI-N and control groups. Additionally, both CAI-K and CAI-N groups displayed higher Romberg ratio in the anterior-posterior than controls. During YBT, the CAI-K group showed reduced reach distance in the anterior direction than CAI-N and control groups. SIGNIFICANCE:The CAI-K group relies more on visual feedback during static balance in the mediolateral direction than CAI-N and control groups. Furthermore, the CAI-K group displayed less anterior reach distance during YBT compared to the CAI-N and control groups. Clinicians should consider both psychological and physical factors when designing rehabilitation programs.