No description available.

Dissertation submitted in partial compliance with the requirements for the Masters Degree in Technology: Chiropractic, Durban University of Technology, 2010. / The aim of this study was to determine the inter-examiner reliability of motion palpation to detect joint dysfunction in hindfoot and midfoot joints of asymptomatic feet and feet with chronic ankle instability syndrome. The rationale for this study was that motion palpation is a commonly used assessment tool that is used by the chiropractic profession to detect the need for manipulation of the spine and extremities. Also until the reliability of motion palpation is known, other studies using motion palpation as an assessment tool to detect the need for manipulation in the hindfoot and midfoot are questionable. The study was conducted at Durban University of Technology (DUT). Patients that responded to the adverts were then screened via telephonic interview. The researcher performed a case history, physical examination and a foot and ankle regional examination on each patient. Three masters chiropractic students then independently assessed both the symptomatic and asymptomatic feet of each patient and recorded their results. The data was then statistically analysed using SPSS version 15. It was found that the inter-examiner reliability of motion palpation for detecting restrictions in feet with chronic ankle instability syndrome was fair and for detecting instability, there was moderate reliability. In the asymptomatic group the examiners showed to have poor reliability in detecting restrictions and moderate reliability in detecting instability. Inter-examiner reliability was better in the symptomatic group and in this group examiners had more agreement on detecting instability as opposed to restrictions. This study has showed that inter-examiner reliability ranged from poor to moderate in the symptomatic and asymptomatic group with the reliability ranging from poor to moderate. Therefore, one can conclude that motion palpation can be used as an assessment tool to detect joint dysfunction in hindfoot and midfoot joints. However, further studies are warranted to address other subjective and objective measurements such as tenderness and range of motion together with motion palpation.

BACKGROUND: Whole body vibration (WBV) platforms are currently used as adjunctive training devices for exercise programs, and have been shown to facilitate flexibility. One of the biggest contributing factors to chronic ankle instability (CAI) is the lack of dorsiflexion after lateral ankle sprains and WBV may be an effective way to increase range of motion in this population. PURPOSE: Determine if WBV done concurrently with static stretching (SS) is more effective then SS alone in improving dorsiflexion ROM in subjects with CAI. METHODS: Subjects were divided into 3 groups (control, static stretch, and static stretch and vibrate). Subjects stretched 4 days/wk for 3 wks for 4 sets of 30 seconds alternating 2 different positions to stretch both the soleus and the gastrocnemius. Imposed vibration at 34 Hz 2mm during the stretches for the stretch group. ANALYSIS: Repeated measures ANOVA was performed using SPSS (version 19), with post-hoc Tukey tests as needed (p<.05). RESULTS: In both the straight and bent leg position, a significant group x time interaction was found for dorsiflexion range of motion. Post hoc tests revealed significance in the SV group between pre-tx and post-tx 1 and pre-tx and post-tx 2. No statistical significance was found between post-tx 1 and post-tx 2 in the SV group or at any time in the N or SS group. DISCUSSION: Static Stretching with vibration increases dorsiflexion ROM in subjects with CAI better than static stretching alone.

Patients with a history of lateral ankle sprain (LAS) may experience different levels of mechanical and/or sensorimotor deficits following their injuries. Although various factors, such as structural damage, sensorimotor adaptation, perceived instability, swelling and/or pain, can develop and perpetuate the condition of chronic ankle instability (CAI), most previous CAI research on biomechanics has considered all patients with CAI as a homogeneous group. Recent research has clustered patients with CAI into six distinct movement patterns during a maximal jump-landing/cutting task. This approach could motivate clinicians to develop appropriate rehabilitation programs for each patient with CAI depending on their movement patterns. However, evaluating patients with CAI for the quality of movement and sensorimotor deficits using a 3D motion capture system and a force plate is not easily accessible in clinical settings. PURPOSE: (i) to identify subgroups within the CAI population based on their movement patterns using inertial measurement unit (IMU) devices and (ii) to characterize each subgroup's functional movement patterns during maximal jump-landing/cutting relative to the uninjured controls. METHODS: A total of 100 patients with CAI (height = 1.76 ± 0.1 m, mass = 74.0 ± 14.9 kg) were assessed according to the Foot and Ankle Ability Measure (FAAM) (ADL: 84.3 ± 7.6%, Sport: 63.6 ± 8.6%) and the Ankle Instability Instrument (AII) (6.7 ± 1.2) and were fit into clusters based on their movement strategy during the maximal jump-landing/cutting task. A total of 21 uninjured controls (height = 1.74 ± 0.1 m, mass = 70.7 ± 13.4 kg) were compared with each cluster. Seven IMU sensors were placed on the base of the lumbar spine, lower and upper legs, and feet and participants performed 5 trials of the maximal jump-landing/cutting test. Joint kinematics in the lower extremity were collected during the task using IMU sensors. Data were reduced to functional curves; kinematic data from the sagittal and frontal planes were reduced to a single representative curve for each plane. Then, representative curves were clustered using a Bayesian clustering technique. Functional analyses of variance were used to identify between-group differences for outcome measures and describe specific movement characteristics of each subgroup. Pairwise comparison functions as well as 95% confidence interval (CI) bands were plotted to determine specific differences. If 95% CI bands did not cross the zero line, we considered the difference significant. RESULTS: Four distinct clusters were identified from the sagittal- and frontal-plane kinematic data. Specific movement patterns in each cluster compared to either uninjured controls or rest of patients with CAI were also identified. CONCLUSION: The IMUs were able to distinguish 4 clusters within the CAI population based on distinct movement patterns during a maximal jump-landing/cutting task. Thus, IMUs can be effective measuring devices to distinguish and characterize multiple distinct movement patterns without relying on a traditional 3D motion capture system. Clinicians should consider utilizing IMU devices to measure and evaluate specific movement patterns in the CAI population during multiplanar demanding tests before developing appropriate treatment interventions in clinical settings.

No description available.

Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2016. / Purpose: Ankle sprains are amongst the most common injury sustained by athletes and the general public. When an ankle is repeatedly sprained it results in chronic ankle instability syndrome (CAIS). This repeated trauma results in disruption of the afferent nerve supply from the injured joint, which affects the motor neuron pool excitability of the peroneal and soleus muscles resulting in arthogenic muscle inhibition (AMI). Traditional treatment for CAIS focuses on rehabilitation of the affected muscles via strength and proprioceptive training. Recent literature has shown that the addition of ankle joint manipulation resulted in improved clinical outcomes in the treatment of CAIS. The mechanism on how joint manipulation affects AMI is under-investigated especially in extremity joints. Thus this study aimed to determine the immediate effect of ankle joint manipulation on peroneal and soleus muscle activity, by assessing surface electromyography (sEMG) H/M ratio to detect a change in the proportion of the total motor neuron pool being recruited, in participants with CAIS. Methods: The study utilised a quantitative, experimental, pre-test post-test study design. Forty two participants with grade I and II CAIS, aged 18-45 years, were randomly allocated into one of three groups. Group one received a single talocrural joint long axis distraction manipulation, group two received a sham manipulation and group three was the control receiving no intervention. sEMG H/M ratio measurements were taken before and immediately after the intervention using a Biopac wireless emg system. Results: The groups were comparable at baseline for age, gender, body mass index and H/M ratio measurements for the soleus and peroneal muscles (p < 0.050). Intra-group analysis of the soleus muscle H/M ratio showed no statistically significant change over time for the manipulation (p = 0.975) and sham (p = 0.056) groups, with the control group showing a statistically significant (p = 0.019) decrease in the H/M ratio. For the peroneal muscle no statistically significant (p > 0.050) differences were observed in any of the three groups. Inter-group analysis of the soleus muscle H/M ratio measurements showed no statistically significant differences between the three groups (p = 0.470; F = 1.010) over time, with Tukey’s HSD post-hoc test revealing a statistically significant (p = 0.028) difference being observed between the sham and control groups in terms of post soleus muscle H/M ratio measurements. Conclusion: This study failed to show that ankle joint manipulation affects the soleus and peroneal muscles in terms of H/M ratio measurements in participants with CAIS. There may have been a trend of an effect of the sham and manipulation interventions counteracting the muscle fatigue experienced in the control group, however further investigation is required. / M

Submitted by KARINA APARECIDA RODRIGUES null (kaarodrigues@gmail.com) on 2016-02-12T17:41:35Z No. of bitstreams: 1 A INFLUÊNCIA DA FADIGA NOS MÚSCULOS EVERSORES.pdf: 2242940 bytes, checksum: 172937512799242c5f55d9082f295349 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-02-15T11:30:53Z (GMT) No. of bitstreams: 1 rodrigues_ka_me_guara.pdf: 2242940 bytes, checksum: 172937512799242c5f55d9082f295349 (MD5) / Made available in DSpace on 2016-02-15T11:30:53Z (GMT). No. of bitstreams: 1 rodrigues_ka_me_guara.pdf: 2242940 bytes, checksum: 172937512799242c5f55d9082f295349 (MD5) Previous issue date: 2016-01-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A entorse do tornozelo em inversão e flexão plantar é uma das lesões mais comuns que ocorrem nas atividades de vida diária e no esporte. Embora os sintomas agudos possam se resolver rapidamente, muitos indivíduos relatam persistência de dor e instabilidade. Este tipo de lesão frequentemente acontece na fase final de um treino ou competição, e mesmo sabendo que a entorse é multifatorial, tal particularidade propicia estabelecer uma relação entre o evento da entorse e a fadiga. Diante disto, o presente estudo propõe analisar a latência e a intensidade de ativação dos músculos fibulares curto e longo em condições de fadiga, e ainda comparar indivíduos com estabilidade e instabilidade do tornozelo. Para esse fim, inicialmente foi desenvolvida uma plataforma simuladora da entorse em inversão e flexão plantar, na qual ambos os pés das voluntárias foram fixados e abaixo de onde se apoiava os pés foram acoplados transdutores de força, um de cada lado. Participaram do estudo 23 voluntárias do sexo feminino, fisicamente ativas, separadas em dois grupos: 11 fizeram parte do grupo estabilidade, não apresentavam histórico de lesão no complexo articular do tornozelo nos últimos 12 meses e outras 12 no grupo instabilidade funcional, classificadas pelo Questionário Cumberland Ankle Instability Tool. Para indução da fadiga, inicialmente foi registrada a Contração Isométrica Voluntária Máxima (CIVM) em eversão e flexão plantar. Durante a indução as voluntárias foram orientadas a manter 70% da CIVM. No momento em que a força aplicada fosse menor que 60% da CIVM o protocolo era interrompido e as voluntárias posicionadas em ortostatismo sobre a plataforma simuladora. Antes e após a fadiga foram realizadas dez simulações da entorse bilateralmente de forma randomizada e simultaneamente com o registro do sinal eletromiográfico. Assim, foi possível observar que após a fadiga não houve alteração da latência, no entanto ocorreu uma redução do nível de contração muscular, constatada pela diminuição da amplitude do sinal eletromiográfico. Ainda, não foram notadas diferenças entre os grupos estabilidade e instabilidade e verificouse maior atividade do músculo fibular curto quando comparado ao longo. Portanto, pôde-se concluir que o controle neuromuscular local ficou comprometido em situações de fadiga, devido à redução do nível de atividade dos músculos fibular longo e curto. Além disso, não foi possível observar diferença no comportamento muscular entre tornozelos estáveis e funcionalmente instáveis. / The inversion and plantar flexion ankle sprain is one of the most common injuries that occur in daily life activities and sports. Although acute symptoms can be resolved quickly, many people report persistent pain and instability. This type of injury often occurs in the final phase of a training or competition, and even though the sprain is multifactorial, such particularity provides the establishment of a relationship between the event sprain and fatigue. In this view, the present study aims to analyze the latency and activation intensity of the brevis and longus peroneus muscles in conditions of fatigue and also compare individuals with stability and instability of the ankle. For this purpose it was initially developed a simulated platform sprains in inversion and plantar flexion, in which both feet of the volunteers were fixed and below where rested his feet were coupled force transducers, one on each side. The study included 23 female volunteers, physically active, separated into two groups: 11 were part of the group stability, had no injury history in the joint complex of the ankle in the last 12 months and another 12 in functional instability group, classified by Cumberland Questionnaire Ankle Instability Tool. To induce fatigue, it was initially recorded a Contraction Isometric Maximal Voluntary (MVIC) in eversion and plantar flexion. During the induction, the participants were instructed to maintain 70% of the MVIC. At the time the force applied was below 60% of the MVIC the protocol was interrupted and the volunteers placed in standing position on the simulator platform. Before and after fatigue were held ten simulations sprain bilaterally randomly and simultaneously to record the electromyographic signal. Thus, it was observed that after the fatigue did not change the latency, but there was a reduction of muscle contraction level, evidenced by the reduction in amplitude of the electromyographic signal. Still, there were no noticeable differences between the groups stability and instability and there was a higher activity of the peroneus brevis compared to longus. Therefore, it was concluded that the local neuromuscular control was compromised in fatigue situations, due to reduced activity level of the peroneus longus and brevis muscles. Moreover, it was not possible to observe difference in muscle behavior between stable and unstable functionally ankles.

Ankle sprains are among the most common injuries for participants in running and jumping sports. Following an initial sprain injury, many (30-40%) will develop chronic ankle instability (CAI), characterized by a perception of instability and repeated sprain injuries. Quasi-static test methods indicate poor postural stability and joint position sense (JPS) as associated motor control deficits. Little research, though, has investigated ankle motor control under dynamic (simulated sport) or fatigue conditions. To better understand factors contributing to the increased sprain rate in adults with CAI, three studies were completed investigating the roles of running speed, fatigue, and ankle bracing on motor control in adults with CAI. First, two groups with and without ankle instability performed dynamic athletic maneuvers at each of two running speeds. Joint kinematics and kinetics were measured to identify differences in motor control strategies. Participants also completed two quasi-static tests (JPS and single leg drop landings). The level of correspondence between quasi-static and dynamic test methods was of particular interest. A second study compared fatigue development and fatigue adaptations when executing single leg drop landings. Strength loss and ratings of perceived exertion measured fatigue development, and joint kinematics, kinetics, and muscle activation quantified drop landing performance. A final study examined whether ankle braces, a common treatment for ankle sprains, retained their effectiveness when an athlete was fatigued. JPS and ankle stiffness were measured before and after a fatigue protocol while using each of three brace conditions. Overall, results indicated that adults with CAI exhibit distinct adaptations to changes in speed and to fatigue that may increase their risk for ankle reinjury. Specific changes, however, depended on the particular activity being performed. Single leg drop landing kinematics may be a good representation of kinematics during dynamic athletic performance. Neither test brace improved JPS following fatigue, but each may be effective in providing mechanical stiffness compared to an unbraced condition. The effectiveness of a particular test brace, however, may be gender-specific. Future work should focus on identifying the benefits of different braces under broader conditions to help inform brace selection. / Ph. D.

Context: Individuals with chronic ankle instability (CAI) rely more on visual information during postural control due to impaired proprioceptive function. The increased reliance on visual information may increase the risk of injury when their vision is limited during complex sports activities. Stroboscopic glasses may help elicit sensory reweighting during postural control. Therefore, we assumed that the glasses would induce and train CAI patients to reweight sensory information for the somatosensory system during dynamic balance training. Purpose: (1) to identify the effects of the 4-week dynamic balance training on the reliance of visual information during postural control in patients with CAI and (2) to compare the effects of the 4-week dynamic balance with and without stroboscopic glasses on postural control in patients with CAI. Methods: This study was a randomized controlled trial. Twenty-eight CAI patients were equally assigned to one of 2 groups: a strobe group (6 males and 8 females) or a control group (8 males and 6 females). The 4-week dynamic balance training consisted of multiple single-legged exercises. The strobe group wore stroboscopic glasses during the training, but the control group did not. The main outcome measures included the following: self-reported function measures, static postural control (center of posture (COP)-based measures), and dynamic postural control including the Dynamic Postural Stability Index (DPSI), and the Star Excursion Balance Test (SEBT). There were 3 visual conditions in the static postural control (eyes-open (EO), strobe vision (SV), and eyes-closed (EC)), and 2 conditions in the dynamic postural control (EO and SV). Two-way randomized block ANOVAs were used to assess changes in postural control in each group and condition by using pretest-posttest mean differences. Results: The strobe group showed a higher difference in COP velocity in medial-lateral direction (VelML) and vertical stability index (VSI) under the SV condition compared with the control group (p = .005 and .004, respectively). In addition, the strobe group had significant decreases in VelML, DPSI, and VSI at the posttest compared with the pretest (p = .0001, .01, and .005, respectively). Conclusion: The 4-week dynamic balance training with stroboscopic glasses appeared to be effective in improving postural control and altering visual reliance in patients with CAI.

Purpose: To determine the effect of Strain Counterstrain (SCS) on strength, dynamic balance and subjective sense of instability in individuals with chronic ankle instability (CAI). Subjects: Twenty seven volunteers (17 females and 10 males) between the ages of 18 and 55 (mean ± SD age: 33.6 ± 8.8) with a history of CAI who met the inclusion/exclusion criteria were randomly assigned to the control group (n= 13) and the experimental group (n=14). Methods: All subjects signed an informed consent, completed a demographic questionnaire and the foot and ankle ability measure (FAAM), and underwent a standard evaluation, ankle isokinetic testing and the star excursion balance test (SEBT) at the onset of the study. All subjects participated in a home exercise program and received a SCS treatment or a sham treatment once a week. At four weeks all subjects repeated the initial testing and completed a global rating of change (GROC) form. The primary aim was examined with a 2-way analysis of variance (ANOVA) with the treatment group (SCS versus sham) as the between subjects independent variable and time (baseline and four weeks) as the within subjects independent variable. Results: A significant group-by-time interaction was found for seven directions in the SEBT (p< 0.031) while no significant interaction was found for ankle strength (p>0.76). For subjective measures, no significant group-by-time interaction was found for the FAAM (p>0.548), but the GROC revealed a significant difference (p=0.014) in the mean score for the experimental group (3.92 ± 1.66) when compared to the control group (2.43 ± 1.66). Conclusions: Although SCS does not appear to have an effect on strength and subjective ankle function in subjects with CAI, it appears that SCS can lead to an improvement in dynamic ankle stability and the subjective sense of ankle instability. Recommendations: Continued research on the effectiveness of SCS in CAI and other sprain injuries is needed to confirm the results of this study. Given the significant rate of ankle sprain recurrence in this population, long-term studies are necessary. Lastly, very little evidence exists on the effects of SCS and the theoretical framework of this technique.