The assessment and treatment of postural disorders in cerebellar ataxia: a systematic review.

Gait and balance disorders are often major causes of handicap in patients with cerebellar ataxia. Although it was thought that postural and balance disorders in cerebellar ataxia were not treatable, recent studies have demonstrated the beneficial effects of rehabilitation programs. This article is the first systematic review on the treatment of postural disorders in cerebellar ataxia. Nineteen articles were selected, of which three were randomized, controlled trials. Various aetiologies of cerebellar ataxia were studied: five studies assessed patients with multiple sclerosis, four assessed patients with degenerative ataxia, two assessed stroke patients and eight assessed patients with various aetiologies. Accurate assessment of postural disorders in cerebellar ataxia is very important in both clinical trials and clinical practice. The Scale for the Assessment and Rating of Ataxia (SARA) is a simple, validated measurement tool, for which 18 of the 40 points are related to postural disorders. This scale is useful for monitoring ataxic patients with postural disorders. There is now moderate level evidence that rehabilitation is efficient to improve postural capacities of patients with cerebellar ataxia - particularly in patients with degenerative ataxia or multiple sclerosis. Intensive rehabilitation programs with balance and coordination exercises are necessary. Although techniques such as virtual reality, biofeedback, treadmill exercises with supported bodyweight and torso weighting appear to be of value, their specific efficacy has to be further investigated. Drugs have only been studied in degenerative ataxia, and the level of evidence is low. There is now a need for large, randomized, controlled trials testing rehabilitation programs suited to postural and gait disorders of patients with cerebellar ataxia.

Measuring verticality perception after stroke: why and how?

About 80 papers dealing with verticality after stroke have been published in the last 20years. Here we reviewed the reasons and findings that explain why measuring verticality perception after stroke is interesting. Research on verticality perception after stroke has contributed to improve the knowledge on brain mechanisms, which build up and update a sense of verticality. Preliminary research using modern techniques of brain imaging has shown that the posterior lateral thalamus and the parietal insular cortex are areas of interest for this internal model of verticality. How they interact and are critical remains to be investigated. From a clinical standpoint, it has now been clearly established that biases in verticality perception are frequent after a stroke, causing postural disorders. Measuring the postural vertical with the wheel paradigm has allowed elucidating the mechanisms of lateropulsion, leading or not to a pushing. Schematically, patients with a hemispheric stroke align their erect posture with an erroneous reference of verticality, tilted to the side opposite the lesion. In patients with a brainstem stroke lateropulsion is usually ipsilesional, and results rather from a pathological asymmetry of tone, through vestibulo-spinal mechanisms. These evolutions of concepts and measurement standards of verticality representation should guide the emergence of rehabilitation programs specifically dedicated to the sense of verticality after stroke. Indeed, several pilot studies using appropriate somatosensory stimulation suggest the possibility to recalibrate the internal model of verticality biased by the stroke, and to improve uprightness. Vestibular stimulations seem to be less relevant and efficient.

Sensory reweighting in controls and stroke patients.

OBJECTIVE: To test sensitivity to proprioceptive, vestibular and visual stimulations of stroke patients with regard to balance. METHOD: The postural control of 20 hemiparetic patients after a single hemispheric stroke that had occurred at least 6 months before the study along with 20 controls was probed with vibration, optokinetic, and vestibular galvanic stimulations. Balance was assessed using a force platform (PF) with two miniature inertial sensors placed on the head (C1) and the trunk (C2) under each sensory condition and measured by three composite scores as the mean displacement of the body (PF, C1, C2) during the stimulation. A subject with a composite score greater than the 75th percentile of the composite scores found in the control subjects was arbitrarily considered to be sensitive to that stimulation. RESULTS: Both control and stroke patients showed large inter-individual variations in response to the three types of sensory stimulation. Among the hemiparetic patients, nearly 65% were sensitive to the optokinetic stimulation, 60% to the galvanic stimulation and 65% to the vibration stimulation. In contrast to the control group, all the hemiparetic subjects were sensitive to at least one type of stimulation. CONCLUSION: Stroke patients are highly dependent on visual, proprioceptive and vestibular information in order to control their standing posture and individually differ in their relative sensitivity to each type of sensory stimulation. SIGNIFICANCE: Contrarily to what one might suppose, the increased visual dependence manifested by stroke patients does not necessarily entail any neglect of proprioceptive and vestibular information.

[Early rehabilitation for neurologic patients]. / Intérêt d'une rééducation précoce pour les patients neurologiques.

Rehabilitation improves the functional prognosis of patients after a neurologic lesion, and tendency is to begin rehabilitation as soon as possible. This review focuses on the interest and the feasibility of very early rehabilitation, initiated from critical care units. It is necessary to precisely assess patients' impairments and disabilities in order to define rehabilitation objectives. Valid and simple tools must support this evaluation. Rehabilitation will be directed to preventing decubitus complications and active rehabilitation. The sooner rehabilitation is started; the better functional prognosis seems to be.

New rehabilitation program for intermittent claudication: Interval training with active recovery: pilot study.

BACKGROUND: Peripheral arterial disease (PAD) is one of the complications of atherosclerosis. Intermittent claudication is the second stage of PAD. In controlled studies on patients with Stage II PAD, intensive rehabilitation training has proved effective for improving the walking distance in this population. The objective of this prospective study was to determine the effects of treadmill interval training followed by active recovery (low-intensity exercise). METHODS AND RESULTS: Eleven patients with Stage II peripheral arterial disease were included in a rehabilitation program (mean age 68.3±10.3 years) for five days a week during two weeks including global exercises, exercises below and above the level of injury. The interval training program consisted of treadmill training for 30minutes twice a day (morning and evening) with a progressively increased intensity: the first week speed was increased and the second week slope was increased. Each session included five six-minute cycles. Each cycle was made of three minutes of active workout followed by three minutes of active recovery. RESULTS: All patients improved their walking distance, from a mean of 610 m (120-1930) at the beginning of the program to a mean of 1252 m (320-2870) at the end (P=0.003). All patients were very motivated by the rehabilitation training program No adverse event was reported. CONCLUSION: This study showed that an interval training program with active recovery was effective and safe for patients with Stage II peripheral arterial disease, the patients' motivation was high. This study must now be validated by a clinical trial.

Somaesthetic perception of the vertical in spinal cord injured patients: a clinical study.

PURPOSE: The perception of verticality results from the integration of vestibular, visual and somatosensory information. Spinal cord injured patients with complete paraplegia have total somatosensory deafferentation below a certain metameric segment. In our study, we were interested in the implication of somatosensory signal in the construction of verticality and in the possible effect of somatosensory loss on spatial representation. METHOD: We analysed haptic and postural aspects of perceived verticality in 14 spinal cord injured patients with complete paraplegia and in an age- and gender-matched group of 13 controls. We also conducted a structured interview on the existence of vertigo or postural instability in daily life. RESULTS: The spinal cord injured patients perceived verticality without any significant directional bias in the orientation of the vertical but with a greater uncertainty than control subjects, both in haptic and postural modalities. If paraplegic did not report vertigo, half described an altered spatial perception without vision. CONCLUSION: The present results confirm the importance of sensory input from the trunk and the lower limbs in the perception of the vertical. However, visual and vestibular information appear to compensate for somatosensory deafferentation.