Deep Brain Stimulation Effects on Gait Pattern in Advanced Parkinson's Disease Patients.

BACKGROUND: Gait disturbance accompanies many neurodegenerative diseases; it is characteristic for Parkinson's disease (PD). Treatment of advanced PD often includes deep brain stimulation (DBS) of the subthalamic nucleus. Regarding gait, previous studies have reported non-significant or conflicting results, possibly related to methodological limitations. OBJECTIVE: The objective of this prospective study was to assess the effects of DBS on biomechanical parameters of gait in patients with PD. METHODS: Twenty-one patients with advanced PD participated in this prospective study. Gait was examined in all patients using the Zebris FDM-T pressure-sensitive treadmill (Isny, Germany) before DBS implantation and after surgery immediately, further immediately after the start of neurostimulation, and 3 months after neurostimulator activation. We assessed spontaneous gait on a moving treadmill at different speeds. Step length, stance phase of both lower limbs, double-stance phase, and cadence were evaluated. RESULTS: In this study, step length increased, allowing the cadence to decrease. Double-stance phase duration, that is, the most sensitive parameter of gait quality and unsteadiness, was reduced, in gait at a speed of 4.5 km/h and in the narrow-based gaits at 1 km/h (tandem gait), which demonstrates improvement. CONCLUSION: This study suggests positive effects of DBS treatment on gait in PD patients. Improvement was observed in several biomechanical parameters of gait.

Botulinum Toxin Modulates Posterior Parietal Cortex Activation in Post-stroke Spasticity of the Upper Limb.

Post-stroke spasticity (PSS) is effectively treated with intramuscular botulinum toxin type A (BoNT-A), although the clinical improvement is likely mediated by changes at the central nervous system level. Using functional magnetic resonance imaging (fMRI) of the brain, this study aims to confirm and locate BoNT-A-related changes during motor imagery with the impaired hand in severe PSS. Temporary alterations in primary and secondary sensorimotor representation of the impaired upper limb were expected. Thirty chronic stroke patients with upper limb PSS undergoing comprehensive treatment including physiotherapy and indicated for BoNT treatment were investigated. A change in PSS of the upper limb was assessed with the modified Ashworth scale (MAS). fMRI and clinical assessments were performed before (W0) and 4 weeks (W4) and 11 weeks (W11) after BoNT-A application. fMRI data were acquired using 1.5-Tesla scanners during imagery of finger-thumb opposition sequences with the impaired hand. At the group level, we separately modeled (1) average activation at each time point with the MAS score and age at W0 as covariates; and (2) within-subject effect of BoNT-A and the effect of time since W0 as independent variables. Comprehensive treatment of PSS with BoNT-A significantly decreased PSS of the upper limb with a maximal effect at W4. Task-related fMRI prior to treatment (W0) showed extensive activation of bilateral frontoparietal sensorimotor cortical areas, bilateral cerebellum, and contralesional basal ganglia and thalamus. After BoNT-A application (W4), the activation extent decreased globally, mostly in the bilateral parietal cortices and cerebellum, but returned close to baseline at W11. The intra-subject contrast revealed a significant BoNT-A effect, manifesting as a transient decrease in the activation of the ipsilesional intraparietal sulcus and superior parietal lobule. We demonstrate that BoNT-A treatment of PSS of the upper limb is associated with transient changes in the ipsilesional posterior parietal cortex, possibly resulting from temporarily altered sensorimotor upper limb representations.

Effect of Gait Imagery Tasks on Lower Limb Muscle Activity With Respect to Body Posture.

The objective of this study was to evaluate the effect of gait imagery tasks on lower limb muscle activity with respect to body posture. The sitting and standing position and lower limb muscle activity were evaluated in 27 healthy female students (24.4 ± 1.3 years, 167.2 ± 5.2 cm, 60.10 ± 6.4 kg). Surface electromyography was assessed during rest and in three different experimental conditions using mental imagery. These included a rhythmic gait, rhythmic gait simultaneously with observation of a model, and rhythmic gait after performing rhythmic gait. The normalized root mean square EMG values with respect to corresponding rest position were compared using non-parametric statistics. Standing gait imagery tasks had facilitatory effect on proximal lower limb muscle activity. However, electromyography activity of distal leg muscles decreased for all gait imagery tasks in the sitting position, when the proprioceptive feedback was less appropriate. For subsequent gait motor imagery tasks, the muscle activity decreased, probably as result of habituation. In conclusion, the effect of motor imagery on muscle activity appears to depend on relative strength of facilitatory and inhibitory inputs.

Sensorimotor modulation by botulinum toxin A in post-stroke arm spasticity: Passive hand movement.

INTRODUCTION: In post-stroke spasticity, functional imaging may uncover modulation in the central sensorimotor networks associated with botulinum toxin type A (BoNT) therapy. Investigations were performed to localize brain activation changes in stroke patients treated with BoNT for upper limb spasticity using functional magnetic resonance imaging (fMRI). METHODS: Seven ischemic stroke patients (4 females; mean age 58.86) with severe hand paralysis and notable spasticity were studied. Spasticity was scored according to the modified Ashworth scale (MAS). fMRI examination was performed 3 times: before (W0) and 4 (W4) and 11weeks (W11) after BoNT. The whole-brain fMRI data were acquired during paced repetitive passive movements of the plegic hand (flexion/extension at the wrist) alternating with rest. Voxel-by-voxel statistical analysis using the General Linear Model (GLM) implemented in FSL (v6.00)/FEAT yielded group session-wise statistical maps and paired between-session contrasts, thresholded at the corrected cluster-wise significance level of p<0.05. RESULTS: As expected, BoNT transiently lowered MAS scores at W4. Across all the sessions, fMRI activation of the ipsilesional sensorimotor cortex (M1, S1, and SMA) dominated. At W4, additional clusters transiently emerged bilaterally in the cerebellum, in the contralesional sensorimotor cortex, and in the contralesional occipital cortex. Paired contrasts demonstrated significant differences W4>W0 (bilateral cerebellum and contralesional occipital cortex) and W4>W11 (ipsilesional cerebellum and SMA). The remaining paired contrast (W0>W11) showed activation decreases mainly in the ipsilesional sensorimotor cortex (M1, S1, and SMA). CONCLUSIONS: The present study confirms the feasibility of using passive hand movements to map the cerebral sensorimotor networks in patients with post-stroke arm spasticity and demonstrates that BoNT-induced spasticity relief is associated with changes in task-induced central sensorimotor activation, likely mediated by an altered afferent drive from the spasticity-affected muscles.

Cortical activity modulation by botulinum toxin type A in patients with post-stroke arm spasticity: real and imagined hand movement.

BACKGROUND: Our aim was to use functional magnetic resonance imaging (fMRI) to compare brain activation changes due to botulinum toxin A (BoNT) application between two chronic stroke patient groups with different degree of weakness treated for upper limb spasticity. METHODS: Fourteen ischemic stroke patients with hand weakness and spasticity were studied. Spasticity was scored by modified Ashworth scale (MAS). FMRI was performed 3 times: before (W0) and 4 (W4) and 11 weeks (W11) after BoNT application. Group A: 7 patients (2 males, 5 females; mean age 59.14 years) with hand plegia, who imagined moving fingers. Group B: 7 age-matched patients (6 males, 1 female; mean age 59.57 years) able to perform sequential finger movement. RESULTS: BoNT transiently lowered MAS in W4 in both groups. In group A, activation of the frontal premotor cortex dominated and persisted for all three fMRI sessions whereas the ipsilesional cerebellum and cortex bordering bilateral intraparietal sulcus activation changed over time. Between-session contrasts showed treatment-related activation decreases in the mesial occipitoparietal and lateral occipital cortex. In group B, brain activation was markedly reduced after BoNT (W4). Whereas some of these areas manifested only transient reduction and expanded again at W11, in others the reduction persisted. CONCLUSION: Study of two age-matched groups with mild and severe weakness demonstrated different effects of BoNT-lowered spasticity on sensorimotor networks. Group A performing movement imagery manifested BoNT-induced reduction of activation in structures associated with visual imagery. Group B performing movement manifested reduced activation extent and reduced activation of structures outside classical motor system, suggestive of motor network normalization.

Central facial paresis and its impact on mimicry, psyche and quality of life in patients after stroke.

AIM: Using functional scales and face video analysis, changes in central facial paresis are monitored in patients with stroke after orofacial therapy and correlations between changes in mimicry, mental function and overall quality of life of patients after stroke are made. MATERIALS AND METHODS: A prospective randomized study of patients after stroke with facial paresis. The functional status of the experimental group of 50 cases with orofacial regulation therapy and 49 control cases without mimicry therapy is observed after four weeks of rehabilitation. RESULTS: Changes in mimicry functions evaluated by the House-Brackmann Grading System (HBGS) clinical range and using 2D video analysis of the distance between the paretic corner of the mouth and earlobe at rest and during smiling were statistically better in the experimental group than in controls. Changes in mental function - depression using Beck Depression Inventory and changes in the quality of life using Bartle index and modified Rankin score (scale) were significantly greater in the experimental group. There was a very close relationship between the changes in mimicry, mental state and overall quality of life according to the Spearman correlative coefficient. CONCLUSION: Orofacial rehabilitation therapy for patients with paresis after stroke has a significant influence on the adjustment of mimicry, mental functions and overall quality of life after 4 weeks of treatment.

Cortical activation changes in patients suffering from post-stroke arm spasticity and treated with botulinum toxin a.

BACKGROUND AND PURPOSE: Botulinum toxin (BoNT) treatment relieves focal arm spasticity after stroke, likely acting at several hierarchical levels of the motor system. The central correlate of BoNT-induced spasticity relief may be detected using repeated functional MRI (fMRI) during motor task. METHODS: Five patients (4 males, 1 female, mean age 67 years) with hemiparesis and distal arm spasticity after chronic ischemic stroke were studied. FMRI was performed while moving the paretic hand in three sessions: before and 4 and 11 weeks after BoNT treatment. RESULTS: Arm spasticity significantly decreased following BoNT treatment across the group (mean modified Ashworth scale change .6). FMRI prior to BoNT treatment showed extensive bilateral active networks, whereas post-BoNT activation was limited to midline and contralateral sensorimotor cortices, and the third examination, when the toxin effect has worn off, again showed extensive activation similar to pre-BoNT examination. Post-BoNT session 2 compared to sessions 1 and 3 demonstrated a significantly less activation in contralateral frontoparietal areas including inferior frontal, postcentral, and middle frontal gyri as well as transient crossed cerebellar activation. CONCLUSION: Relief of post-stroke arm spasticity may be associated with changes at several hierarchical levels of the cortical sensorimotor system, including the prefrontal cortex.

BoNT-A related changes of cortical activity in patients suffering from severe hand paralysis with arm spasticity following ischemic stroke.

BACKGROUND: Investigations were performed to localize and analyze the botulinum toxin (BoNT-A) related changes of cerebral cortex activation in chronic stroke patients suffering from severe hand paralysis with arm spasticity. Effects on task- related cerebral activation were evaluated by functional magnetic resonance imaging (fMRI). METHODS: 14 patients (5 males, 9 females, mean age 55.3 years) suffering from upper limb post-stroke spasticity were investigated. The change of arm spasticity was assessed by using the modified Ashworth scale (MAS). FMRI sessions were performed before (W0), four weeks (W4) and 11 weeks (W11) after BoNT-A application. Patients were scanned while performing imaginary movement with the impaired hand. Group fMRI analysis included patient age as a covariate. RESULTS: BoNT-A treatment was effective in alleviation of arm spasticity. Mean MAS was at Week 0: 2.5 (SD 0.53), at Week 4: 1.45 (SD 0.38), at Week 11: 2.32 (SD 0.44). Task-related fMRI prior to the treatment showed extensive activation of bilateral frontoparietal sensorimotor cortical areas, anterior cingulate gyrus, pallidum, thalamus and cerebellum. Effective BoNT-A treatment (W4) resulted in partial reduction of active network volume in most of the observed areas, whereas BoNT-free data (W11) revealed further volume reduction in the sensorimotor network. On direct comparison, significant activation decreases associated with BoNT-A treatment were located in areas outside the classical sensorimotor system, namely, ipsilesional lateral occipital cortex, supramarginal gyrus and precuneus cortex. On comparison of W4 and W11, no activation increases were found, instead, activation further decreased in ipsilesional insular cortex, contralesional superior frontal gyrus and bilateral frontal pole. CONCLUSIONS: Whole brain activation patterns during BoNT-A treatment of post-stroke arm spasticity and further follow up document predominantly gradual changes both within and outside the classical sensorimotor system.

Musculoskeletal problems as an initial manifestation of Parkinson's disease: a retrospective study.

OBJECTIVE: The purpose of this study was to review the prevalence of musculoskeletal pain in the prodromal phase of PD, before the PD diagnosis is made. METHODS: A retrospective review of 82 PD patients was performed. Hospital inpatient notes and outpatient clinic admission notes were reviewed. The initial complaints prompting patients to seek medical attention were noted, as were the initial diagnoses. The symptoms were considered retrospectively to be associated with PD. RESULTS: Musculoskeletal pain was present as a prodromal PD symptom in 27 (33%) cases initially diagnosed with osteoarthritis, degenerative spinal disease, and frozen shoulder. The mean time from the initial symptom appearance to dopaminergic treatment was 6.6 years in the musculoskeletal pain group and 2.3 years in the group with typical PD signs. Significant improvement of musculoskeletal pain after the initiation of dopaminergic treatment was present in 23 (85%) cases. CONCLUSIONS: Of the PD patients who went on to develop motor features of PD, one third manifested musculoskeletal pain as the initial symptom. A good response to L-DOPA therapy was seen in 85% of cases presenting with musculoskeletal pain. Our findings suggest that musculoskeletal pain may be a significant feature in earlier PD stages.

Functional categorization of the individual morphology of the scapula.

The morphologic variations of the shoulder blade have not yet been evaluated in clinical medicine. We observed that subjects with less standard shapes of the shoulder blade often suffer from musculo-skeletal shoulder syndromes with concurrent intrinsic impingement syndromes or, more precisely, partial-thickness rotator cuff tears. This experience became a basis for an experiment, in which we categorized individual phenotypes of the shoulder blade. A clinically useful finding of the presented study is a tool for predicting patients at risk for manifestations of impingement syndrome and also for prediction of easy or complicated restoration of neuromuscular stabilization of the shoulder. Lower functional potential of the external rotator muscles of the shoulder is in close relation to the individual shape of the shoulder blade, for the most part with the cranio-caudal dimension of the infraspinous fossa.