Active Ankle Movements Research Articles

Avaliação do volume de fluxo venoso da bomba sural por ultra-sonografia Doppler durante cinesioterapia ativa e passiva: um estudo piloto

CONTEXTO: O fisioterapeuta na unidade hospitalar atua sobre os efeitos da hipoatividade ou inatividade do paciente acamado. Na prática diária, a contração do músculo da panturrilha é difundida entre os profissionais de saúde no ambiente hospitalar, principalmente nos períodos de pré e pós-operatório, como forma de diminuir a estase venosa e os riscos de trombose venosa profunda nos membros inferiores. OBJETIVO: Avaliar o volume de fluxo venoso na bomba sural, através de ultra-sonografia doppler, durante cinesioterapia ativa e passiva (flexão plantar do tornozelo). MÉTODOS: A amostra foi constituída por 30 indivíduos escolhidos aleatoriamente e submetidos a ultra-sonografia doppler da veia poplítea direita, visando mensurar o volume de fluxo sanguíneo em quatro momentos: repouso, compressão manual da panturrilha, movimentação passiva e ativa do tornozelo em flexão plantar. Na análise dos resultados, utilizou-se o teste t, sendo utilizado um valor de p < 0,05 como índice de significância estatística. RESULTADOS: Na amostra constituída, 16 eram do sexo feminino e 14 do sexo masculino, apresentando as seguintes médias: idade (31,57 anos), altura (1,68 m), peso (68,25 kg) e índice de massa corporal (24,16). Na análise estatística, a flexão plantar do tornozelo realizada de forma passiva, quando comparada ao valor basal, é significante (p < 0,000056) em relação à ativação da bomba sural, embora não tanto quanto o exercício ativo (p < 0,0000016). Também mostrou significância a compressão manual do músculo tríceps sural em relação ao exercício passivo (p < 0,000000081). CONCLUSÃO: Neste estudo, a flexão plantar do tornozelo de forma ativa mostrou-se estatisticamente mais eficaz do que a passiva na ativação da bomba sural, aumentando o volume do fluxo de sangue na veia poplítea e diminuindo a estase venosa nos membros inferiores.

Functional response to active and passive ankle movements with clinical correlations in patients with primary progressive multiple sclerosis

Patients with multiple sclerosis (MS) activate a more diffuse cortical network than do healthy subjects when they perform motor tasks. This brain functional reorganisation might contribute to the limiting of disability, but it is unclear whether there is a loss of regional activation in more advanced disease. The aim of this study was to assess whether functional reorganisation diminishes in more disabled patients with primary progressive (PP) MS. The differences in the fMRI response to active and passive movements of the dominant ankle of 13 patients and 16 controls were assessed. The relationships between functional activation and disability and brain lesion load and atrophy were investigated.Patients showed greater fMRI activation than controls with passive movements in the superior temporal gyrus, rolandic operculum, and putamen. The fMRI response to active and passive movements in the ipsilateral inferior frontal gyrus was lower in patients with greater disability and greater brain T2 lesion load, respectively. Furthermore, the fMRI activation with active movements in the contralateral cerebellum was lower in patients with worse mobility. The increased activity with passive movements in regions that participate in sensori-motor integration, such as the putamen, reflects true functional reorganisation, since passive movements induce brain activation through sensory afferents only. The inverse correlation between the fMRI response in regions that are associated with motor control, and clinical or MRI measures of disease progression, suggests that there is a loss of distributed activation in more disabled patients. This may inform future treatment strategies.

FMRI of the lumbar spinal cord during a lower limb motor task.

This study applied spinal fMRI to the lumbar spinal cord during lower limb motor activity. During active ankle movement, activity was detected in the lumbar spinal cord motor areas and sensory areas bilaterally. During passive ankle movement, activity was detected in the motor and sensory areas in lower lumbar spinal cord segments and motor activity in higher lumbar spinal cord segments. Spinal fMRI detects patterns of activity consistent with known physiology and can be used to reliably assess activity in the lumbar spinal cord during lower limb motor stimulation. This study affirms spinal fMRI as an effective tool for assessing spinal cord function and increases its potential as a clinical tool.

Textured insole effects on ankle movement discrimination while wearing athletic shoes

Aspects of athletic footwear were examined for their relationship to subjects' discrimination between different extents of inversion at the ankle. Testing was conducted separately on both feet with elite netballers who made discrete, active ankle movements while standing on an apparatus in an upright, non-restrained and weightbearing posture. Wearing conventional athletic socks only did not enhance discrimination over that achieved when barefoot. Movement discrimination scores were significantly worse when subjects wore their athletic shoes and socks, as compared to barefoot data collected at the same time. On the final occasion of testing, the addition of textured insoles to the shoes was found to restore movement discrimination back to barefoot levels. This outcome was interpreted in terms of enhanced cutaneous feedback, applying at the surface of the sole of the foot and the raised surface of the insole, serving to enhance feedback from movement. Across the 36 weeks of the study, movement discrimination scores for the barefoot condition showed significant improvement, a finding which is consistent with previous data gathered from athletes also engaged in wobbleboard training.

A direct method for quantitative measurement of ankle proprioception

This study describes a direct method for the quantitative measurement of ankle proprioception, by measuring the ability of subjects to match reference ankle joint positions using the ‘Polhemus Isotrak’ 3-Dimensional Goniometry System. Five normal adult males (10 ankles) were studied, i.e. no history of ankle problems. Ankle proprioception was measured with a difference mean proprioception difference of 0.01–1.14°. No variation in the ankle proprioception was found with demographic variables of age, height and weight. In addition, no significant differences in ankle proprioception were present about any of the three anatomic axes of ankle motion: between passive and active ankle movements and with extended and flexed positions of knee.

Early Postoperative Ankle Exercise A Study of Postoperative Lateral Malleolar Fractures

Fifty-three patients with dislocated lateral malleolar fractures were randomly selected after operation for either active ankle movement and weight bearing in an orthosis or no ankle movement but weight bearing in a walking cast. At follow-up examinations after three, six, and 18 months, no differences were found between the groups except for a better linear analogue scale result at three months for the orthosis group. Active ankle movements do not improve the rehabilitation of surgically treated lateral malleolar fractures.

Identifying the afferents involved in movement-induced pain alleviation in man.

It has been clearly established that the perception of nociceptive stimulus decreases in intensity when movement is initiated in the part of the body to which the stimulus is applied. The pain alleviation is probably at least partly due to the activation of afferents which occurs during the movement. The present experiments were carried out with a view to investigating which groups of afferent fibres is mainly responsible for the gating of the nociceptive messages which occurs during movements. In eight volunteers we investigated the changes in the amplitude of the nociceptive leg flexion reflex (RIII) when the subjects were at rest, when they were performing active or passive ankle movements and when the spindle proprioceptive pathway was mobilized by applying vibratory stimulation to the Achilles tendon. Similar experiments were also carried out with eight other volunteers after anaesthetizing the ankle skin mechanoreceptors. This method was chosen because a clear-cut correlation is known to exist between the amplitude of the nociceptive motor reflex and the intensity of the pain perceived by the subject. The data obtained clearly show that anaesthesia of cutaneous mechanoreceptors connected to the large diameter afferent fibres prevented the decrease in the motor response which otherwise accompanied both active and passive movements. Activation of the Ia fibre group by tendon vibration resulted on the contrary in an increase in the amplitude of the motor response. Movement-induced pain alleviation therefore does not mainly involve the activation of the Ia group of fibres.

Kinaesthetic role of muscle afferents in man, studied by tendon vibration and microneurography.

The characteristics of vibration-induced illusory joint movements were studied in healthy human subjects. Unseen by the subject, constant frequency vibration trains applied to the distal tendon of the Triceps or Biceps induced an almost constant velocity illusory movement of the elbow whose direction corresponded to that of a joint rotation stretching the vibrated muscle. Vibration trains of the same duration and frequency applied alternatively to the Biceps and Triceps evoked alternating flexion-extension illusory movements. During successive application of vibration trains at frequencies from 10 to 120 Hz, the perceived velocity of the illustory movements increased progressively from 10 to 70-80 Hz, then decreased from 80 to 120 Hz. The maximal perceived velocity was three times higher during alternating vibration of the Biceps and Triceps than during single muscle stimulation. Unit activity from 15 muscle spindle primary endings and five secondary endings located in Tibialis anterior and Extensor digitorum longus muscles were recorded using microneurography in order to study their responses to tendon vibration and passive and active movements of the ankle. Primary endings were all activated by low amplitude tendon vibration (0.2-0.5 mm) previously used to induce illusory movements of the elbow. The discharge of some was phase-locked with the vibration cycle up to 120 Hz, while others responded one-to-one to the vibration cycle up to 30-50 Hz, then fired in a sub-harmonic manner at higher frequencies. Secondary endings were much less sensitive to low amplitude tendon vibration. Primary and secondary ending responses to ramp and sinusoidal movements of the ankle joint were compared. During the movement, the primary ending discharge frequency was almost constant, while the secondary ending activity progressively increased. During ankle movements the primary ending discharge appeared mainly related to velocity, while some secondary activities seemed related to both movement velocity and joint angle position. Muscle spindle sensory ending responses to active and passive ankle movements stretching the receptor-bearing muscle (plantar flexion) were qualitatively and quantitatively similar. During passive reverse movements (dorsiflexion) most of the sensory endings stopped firing when their muscle shortened. Active muscle shortening (isotonic contraction) modulated differently the muscle spindle sensory ending discharge, which could stop completely, decrease or some times increase during active ankle dorsiflexion. During isometric contraction most of the muscle spindle sensory endings were activated. The characteristics of the vibration-induced illusory movements and the muscle spindle responses to tendon vibration and to active and passive joint movements strengthened the possibility of the contribution of primary endings to kinesthesia, as suggested by several previous works...