Biomechanical assessment with electromyography of post-stroke ankle plantar flexor spasticity

Spasticity has been defined as a motor disorder characterized by a velocity-dependent increase in tonic stretch reflex (muscle tone). Muscle tone consists of mechanical-elastic characteristics, reflex muscle contraction and other elements. The aims of this study were to determine whether to assess spasticity quantitatively, and to characterize biomechanical and electromyographic spasticity assessment parameters. These assessment parameters were described by investigating the correlation between clinical measures and the response to passive sinusoidal movement with consecutive velocity increments. Twenty post-stroke hemiplegic patients and twenty normal healthy volunteers were included in the study. Five consecutive sinusoidal passive movements of the ankle were performed at specific velocities (60, 120, 180, and 240 degrees/ sec). We recorded the peak torque, work, and threshold angle using a computerized isokinetic dynamometer, and simultaneously measured the rectified integrated electromyographic activity. We compared these parameters both between groups and between different velocities. The peak torque, threshold angle, work, and rectified integrated electromyographic activity were significantly higher in the post-stroke spastic group at all angular velocities than in the normal control group. The threshold angle and integrated electromyographic activity increased significantly and linearly as angular velocity increased, but the peak torque and work were not increased in the post-stroke spastic group. Peak torque, work, and threshold angle were significantly correlated to the Modified Ashworth scale, but the integrated electromyographic activity was not. The biomechanical and electromyographic approach may be useful to quantitatively assess spasticity. However, it may also be very important to consider the different characteristics of each biomechanical parameter.     

The predictive value of lesion and disconnectome loads for upper limb motor impairment after stroke

Neurological Sciences - The putative effect of lesion-induced brain damage on post-stroke upper limb motor impairment can be estimated by overlaying a patient's lesion or its surrogate with key...     

Analysis of high-voltage electrical spinal cord injury using diffusion tensor imaging

The aim of this study was to investigate spinal cord injury (SCI) on the basis of diffusion tensor imaging (DTI) in patients with high-voltage electrical injury. We recruited eight high-voltage electrical injury patients and eight healthy subjects matched for age and sex. DTI and central motor conduction time were acquired in both the patient and control groups. We obtained DTI indices according to the spinal cord levels (from C2 to C7) and cross-section locations (anterior, lateral, and posterior). Fractional anisotrophy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were compared between the two groups; additionally, they were compared in relation to spinal cord level and cross-section location. In the patient group relative to the control group, the FA value decreased and the MD and RD values increased in all of the regions of interest (ROI) with statistical significance (p < 0.05). In the patient group, particularly in the ROIs of the anterior spinal cord compared with the lateral and posterior spinal cords, the FA value decreased with statistical significance (p < 0.05). The DTI indices did not differ by level. DTI revealed the change of diffusion in the spinal cords of patients with high-voltage electrical injury, and corroborated the pathophysiology, myelinopathy and typical anterior spinal cord location of high-voltage electrical SCI already reported in the literature.     

Surgical management of lipomas: Proposal of the Z‐incision design and surgical algorithm based on tumor size

Surgical excision is the treatment of choice for lipomas. However, linear incision methods or minimal extraction techniques often do not provide a sufficient surgical view. Therefore, removing large lipomas is often difficult. To present the Z‐incision and half Z‐incision designs for lipoma extraction, this retrospective study analyzed lipomas surgically excised at our institution between September 2015 and December 2018. The area of surgical field exposed by the Z‐incision versus that exposed by the linear incision was calculated using a schematic model. Cure rate, complications, and surgical field area were investigated. A total of 84 lipomas were included. A Z‐ or half Z‐incision was used to treat 30 lipomas, while a linear incision was used to treat 54 lipomas. The mean diameter of the mass in the Z‐ or half Z‐incision group was 47.7 mm (range, 15–160 mm), larger than that in the linear incision group (25.5 mm; range, 7–59 mm) (p < .001). The Z‐incision involved making rectangular windows by lifting 2 triangular flaps. According to our mathematical model, the Z‐incision provided a larger surgical field area than that provided by the linear incision based on stretched angles (1.81 times larger at 30° and 3.14 times larger at 15°). The Z‐ and half Z‐incisions were successfully performed in all but 1 lipoma (29 lipomas, 96.7%). There was 1 lipoma that resulted in postoperative complications (seroma, 3.3%). The Z‐incision design can be a useful alternative technique for the extirpation of lipomas, especially large lipomas. Here, we proposed a surgical algorithm for lipoma surgery based on tumor size.     

Neural correlates of donepezil-induced cognitive improvement in patients with right hemisphere stroke: A pilot study

Donepezil has been proven effective in the treatment of Alzheimer's disease and vascular dementia. However, its effects on the cognitive neural network have not been fully investigated. The purpose of this study was to evaluate the effect of donepezil on reorganisation of the cognitive neural network in patients with post-stroke cognitive impairment using functional MRI (fMRI). Fourteen patients with stroke in the right hemisphere were enrolled. Participants were randomly assigned to the experimental or the control group. Donepezil (5 mg) or placebo was administered daily for four weeks. Cognitive function assessment was performed before and immediately after treatment, and repeated one month after cessation of treatment. fMRI was performed before and after treatment. Ten out of 14 patients (six in the experimental group, four in the control group) successfully completed all experimental processes. The experimental group showed significant improvements in the Mini-Mental Status Examination during the post-treatment evaluation and one-month follow-up compared to the pre-treatment evaluation (p?<?.05). No improvement was observed in the control group. In the experimental group fMRI showed increased activation in both prefrontal areas, both inferior frontal lobes, and in the left inferior parietal lobe. Increased recruitment of the parieto-frontal networks in the selected patients was considered to be a neural correlate of cognitive improvement induced by donepezil.     

Antihypertensive therapy in patients above age 60. Third interim report of the European Working Party on High blood pressure in Elderly (EWPHE).

Three hundred forty nine hypertensive patients above the age of 60 have entered the double-blind multicentre trial of the European Working Party on High blood pressure in the Elderly (EWPHE). After stratification and randomisation half were treated with one or two capsules containing 25 mg hydrochlorothiazide and 50 mg triamterene and if blood pressure control was insufficient methyldopa was added up to 2 g daily; the other half received matching placebo. No significant differences between the groups were present prior to randomisation. A significant blood pressure difference of 25/10 mm Hg was obtained between the groups and maintained during two years of follow-up. No major disturbances in serum potassium or serum sodium were noted with the present drug combination. However, during the initial phase an increase in serum creatinine and serum uric acid was noted in the actively treated group, which was maintained for two years. Also glucose tolerance was impaired after 2 years in the actively treated group. A favourable influence on prognosis by active treatment can be expected on the basis of the blood pressure reduction and in the absence of major electrolytes disturbances. But this benefit must be proven by observed statistical differences in terminating events between the groups. Therefore the patients are being followed for a longer period of time and more patients are admitted into the trial.