1/25. Interfacing the body's own sensing receptors into neural prosthesis devices.Functional electric stimulation (FES) is today available as a tool in muscle activation used in picking up objects, in standing and walking, in controlling bladder emptying, and for breathing. Despite substantial progress over nearly three decades of development, many challenges remain to provide a more efficient functionality of FES systems. The most important of these is an improved control of the activated muscles. Instead of artificial sensors for feedback, new developments in electrodes to do long-term and reliable recordings from peripheral nerves emphasize the use of the body's own sensors. These are already installed and optimised through millions of years of natural evolution. This paper presents recent results on a system using electrical stimulation of motor nerves to produce movement and using the natural sensors as feedback signals to control the stimulation that can replicate some of the functions of the spinal cord and its communication with the brain. We have used the nerve signal recorded from cutaneous nerves in two different human applications: (1) to replace the external heel switch of a system for correction of spastic drop foot by peroneal stimulation, and (2) to provide an FES system for restoration of hand grasp with sensory feedback from the fingertip. For the bladder function, the sacral root stimulator is a useful control tool in emptying the bladder. To decide when to stimulate, we are at present carrying out experiments on pigs and cats using cuff electrodes on the pelvic nerve and sacral roots to record the neural information from bladder afferents. This information can potentially be used to inhibit unwanted bladder contractions and to trigger the FES system and thereby bladder emptying. Future research will show whether cuffs and other types of electrodes can be used to reliably extract signals from the large number of other receptors in the body to improve and expand on the use of natural sensors in clinical FES systems.- - - - - - - - - - ranking = 1keywords = body (Clic here for more details about this article) |
2/25. Intermittent falls and fecal incontinence as a manifestation of epileptic negative myoclonus in idiopathic partial epilepsy of childhood.We report two children, suffering from idiopathic partial epilepsy, who started to present, in the same period of time, with epileptic negative myoclonus (ENM) in one lower limb and fecal incontinence (FI). Polygraphic recordings showed that ENM was associated with paroxysmal activities distributed over the vertex region. Both ENM and FI disappeared when ethosuximide treatment was started. We hypothesize that, in our patients, ENM in one lower limb and FI depended on a transitory impairment, caused by epileptic activity that altered the functionality of nearby cortical areas, located in fronto-mesial regions, involved in the control of the muscular tone of the lower limbs and of the pelvic floor muscles.- - - - - - - - - - ranking = 5.0940590453297keywords = idiopathic (Clic here for more details about this article) |
3/25. Phenotypic characterisation of autosomal recessive PARK6-linked parkinsonism in three unrelated Italian families.The clinical features of nine patients (three women and six men) affected by PARK6-linked parkinsonism, belonging to three unrelated Italian families, are reported. The occurrence of affected men and women within one generation suggested an autosomal recessive mode of inheritance in all three families. Mean age at disease onset was 36 /- 4.6 years; all cases except one presented with asymmetrical signs, consisting of tremor and akinesia of one upper limb or unilateral short step gait. Affected individuals had a mean age of 57 /- 8.5 years, and average disease duration was 21 /- 7.8 years. Parkinsonian features included benign course, early onset of drug-induced dyskinesias, and a good and persistent response to levodopa. There were no other associated features (i.e., pyramidal or cerebellar signs, dysautonomia, or diurnal fluctuations unrelated to drug treatment). cognition was unaffected. The clinical picture was remarkably similar in all patients; no relevant family-related differences were found. PARK6 disease is a new form of early-onset parkinsonism without other atypical clinical features.- - - - - - - - - - ranking = 35896.040737354keywords = parkinson, parkinsonism (Clic here for more details about this article) |
4/25. spinal cord stimulation facilitates functional walking in a chronic, incomplete spinal cord injured.DESIGN: This paper describes a treatment paradigm to facilitate functional gait in a quadriplegic, asia C spinal cord injured (SCI), wheelchair-dependent subject who presented with some large fiber sensation, sub-functional motor strength in all lower limb muscles, and moderate spasticity. The study utilizes partial weight bearing therapy (PWBT) followed by epidural spinal cord stimulation (ESCS) with the assumption that both treatments would be necessary to elicit a well organized, near effortless functional gait with a walker. Function is defined in terms of accomplishing task-specific activities in the home and community. OBJECTIVES: To demonstrate the feasibility and benefits of combined PWBT and ESCS therapies aimed at promoting functional gait in a wheelchair-dependent asia C SCI subject. SETTING: The Clinical neurobiology and bioengineering research laboratories at Good Samaritan Regional Medical Center, Phoenix, arizona, USA, and the Department of bioengineering, arizona State University, Tempe, arizona, USA. methods: The study began with the application of PWBT. The subject walked on the treadmill until a plateau in gait rhythm generation was reached. Subsequently, ESCS, applied to the lumbar enlargement, was utilized to facilitate PWBT and, later, over-ground walking for a standard distance of 15 m. gait performance was analyzed by measuring average speed, stepping symmetry, sense of effort, physical work capacity, and whole body metabolic activity. RESULTS: PWBT led to improved stereotypic stepping patterns associated with markedly reduced spasticity, but was insufficient for over-ground walking in terms of safety, energy cost, and fatigue. ESCS with PWBT generated immediate improvement in the subject's gait rhythm when appropriate stimulation parameters were used. When compared to the non-stimulated condition, over-ground walking with ESCS across a 15 m distance was featured by a reduction in time and energy cost of walking, sense of effort, and a feeling of 'lightness' in the legs. After a few months of training, performance in speed, endurance, and metabolic responses gradually converged with/without ESCS at this short distance, suggesting a learned response to these conditions. However, at longer distances (eg, 50-250 m), performance with ESCS was considerably superior. The subject was able to perform multiple functional tasks within the home and community with ESCS. CONCLUSION: We propose that ESCS augments the use-dependent plasticity created by PWBT and may be a valuable adjunct to post-SCI treadmill training in asia C subjects. We also conclude that ESCS elicits greater activation of an oxidative motor unit pool, thereby reducing the subject's sense of effort and energetic cost of walking.- - - - - - - - - - ranking = 0.16666666666667keywords = body (Clic here for more details about this article) |
5/25. Quantification of circulating anti-Hu antibody in serial samples from patients with paraneoplastic neurological syndromes: possible correlation of antibody concentration and course of neurological symptoms.Serial samples, spanning an observation period of 4 to 10 years, from five patients with anti-Hu associated paraneoplastic neurological syndromes (PNS) were investigated with an enzyme linked immunosorbent assay (ELISA) employing recombinant HuD protein as antigen. In one patient the anti-Hu antibody concentration converted from negative to highly positive levels after the onset of neurological symptoms. These findings argue in favour of the idea that an autoimmune process, which is generated at the beginning of the neurological disease, causes the anti-Hu associated PNS. serum samples obtained shortly after the beginning of the PNS were available from two other patients. The anti-Hu antibody levels in these latter patients increased from modest to highly positive anti-Hu antibody in follow up samples. In two patients a clear decrease of the anti-HuD antibody concentration together with an improvement of paraneoplastic neurological symptoms after successful tumour treatment were seen. overall these data suggest that there might be a correlation between the anti-HuD antibody level and the clinical course of paraneoplastic neurological symptoms which supports further the hypothesis that an autoimmune process is responsible for the anti-Hu associated paraneoplastic neurological symptoms.- - - - - - - - - - ranking = 2.1666666666667keywords = body (Clic here for more details about this article) |
6/25. Exertional myelopathy in type 2 congenital kyphosis.STUDY DESIGN: A case of lower-extremity myelopathy induced by physical exertion in a patient with Type 2 (failure of segmentation) congenital kyphosis is reported. OBJECTIVE: To describe the uncommon presentation of neurologic sequelae in a patient with Type 2 congenital kyphosis. SUMMARY OF BACKGROUND DATA: Various reports have described neurologic sequelae in patients with Type 1 (failure of formation) congenital kyphosis. To the authors' knowledge, no case of Type 2 congenital kyphosis leading to neurologic symptoms has been reported. methods: A 17-year-old boy presented with a 3-year history of progressively worsening midthoracic back pain. During exertion, numbness developed along the posterior aspects of his legs, and he experienced a wobbly sensation in his lower extremities that prevented his participation in athletic activities. His static and dynamic neurologic examination was unremarkable. However, he developed a wide-based clumsy myelopathic gait when he was asked to run in the halls of the clinic. magnetic resonance imaging demonstrated that the spinal cord was draped over the posterior vertebral body of T10. Anterior thoracic spinal cord decompression and fusion were performed through a seventh rib thoracotomy using a structural rib graft to fill the defect. The anterior 1 cm of bone was left intact so as not to cause any additional instability. RESULTS: The patient tolerated the procedure well and had complete resolution of his exertionally dependent myelopathic symptoms. At this writing, 3 years after surgery, he is involved in the Navy ROTC program. CONCLUSIONS: Although Type 2 congenital kyphosis is a rare entity, it should be followed carefully and corrected surgically when appropriate. A history of exertional myelopathy may be an early sign of spinal cord impingement and is an indication for surgical decompression.- - - - - - - - - - ranking = 0.16666666666667keywords = body (Clic here for more details about this article) |
7/25. Spasticity, strength, and gait changes after surgery for cervical spondylotic myelopathy: a case report.STUDY DESIGN: A case report with repeated measures is presented. OBJECTIVE: To describe an objective method for evaluating changes in upper- and lower-extremity spasticity and strength, as well as temporal and kinematic gait variables, after surgical intervention for cervical spondylotic myelopathy. SUMMARY OF BACKGROUND DATA: Degenerative cervical spinal disease is a common disorder, with some form of spondylosis demonstrated radiographically in more than 80% of those older than 55 years. Normative pre- and postoperative objective data quantifying spasticity, strength, and gait do not exist. methods: A 65-year-old woman underwent C2-C3 anterior cervical discectomy and fusion for progressive myelopathy secondary to a spondylosis and disc herniation. The measure for spasticity and strength at the ankles and elbows and a gait analysis were collected before surgery and at 11 days, 3 and 6 months after surgery. Spasticity and strength were assessed using a dynamometer, and a six-camera video system was used to record the gait. RESULTS: Preoperative left elbow flexor spasticity was more than 10 times greater than the values for the able bodies. It was reduced to normal levels after surgery. Substantial presurgery weakness was present in the elbow flexors and extensors bilaterally. elbow extensor strength was at able-body levels after surgery. gait speed was 57% of the able-body level before surgery and 78% of the able-body level 6 months after surgery. CONCLUSIONS: This case study demonstrated the role of biomechanics in characterizing impairments associated with cervical spondylosis and its surgical intervention. Measures for spasticity, strength, and gait taken before and after surgery indicated a favorable outcome. This report provides a foundation for the continued use of biomechanical methods to measure changes in function and impairments associated with surgical intervention of cervical spine disorders.- - - - - - - - - - ranking = 0.5keywords = body (Clic here for more details about this article) |
8/25. Novel missense mutation and large deletion of GNE gene in autosomal-recessive inclusion-body myopathy.The UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) gene is the causative gene for autosomal-recessive hereditary inclusion-body myopathy (h-IBM). Two sisters affected with autosomal-recessive h-IBM were shown to be compound heterozygous for two novel GNE mutations: a large deletion involving exons 1-9, and a R162C amino acid change in the epimerase domain. This is the first deletion event observed in a GNE allele and expands the molecular pathogenesis of autosomal-recessive h-IBM.- - - - - - - - - - ranking = 0.83333333333333keywords = body (Clic here for more details about this article) |
9/25. Restoration of locomotion in paraplegics with aid of autologous bypass grafts for direct neurotisation of muscles by upper motor neurons--the future: surgery of the spinal cord?OBJECTIVES: paraplegia means a lifelong sentence of sensory loss, paralysis and dependence. Complete spinal cord lesions cannot heal up to now despite intensive experimental research, remarkable efforts and recent achievements in bio-technology and re-engineering. Traumatic paraplegia due to spinal cord injury (SCI) is a quite frequent condition and related to the socio-economical situation of the population. It is experienced disproportionately by young people. The rise in gunshot wounds is dramatic. SCI has appeared refractory to treatment. patients AND methods: Since 1980 G.A.B. had tried surgical repair of the spinal cord (SC) after experimental bisection in rats, and since 1993 research was done on monkeys (macaca fascicularis) to be closer to human physiology. The sciatic nerve was removed and used as an autologous graft from the lateral bundle of the spinal cord (tractus corticospinalis ventro lateralis) to the three muscles of both legs being known to be most important for locomotion: M. gluteus maximus, M. gluteus medius and M. quadriceps femoris. The first fruitful transplantation in a human being was performed in July 2000. RESULTS: The results in rats were promising and fulfilled the requirements of the American Task Force of the National Institute of Neurological and Communicative Disorders and stroke of the US. The results in monkeys confirmed the paradigm so that we performed the first operation in a young lady suffering for four months from complete SC lesion T9 after approval by the ethical committee. First voluntary movements of the connected muscles after 17 months. 27 months after op she was able to walk up to 60 steps with the help of a walker and to climb steps in the water. Improvement is still continuing. DISCUSSION: SCI has appeared refractory to any kind of treatment. Compensatory strategies are still experimental in human beings. Autologous nerve grafts from the spinal cord tissue (the lateral spinal bundle) connected to peripheral muscle nerves seem promising in paraplegics. But the physiology is still unclear when the glutamatergic upper motor neuron connected to motor end-plates (cholinergic) does work like in our patient. CONCLUSION: Further studies in primates and paraplegic patients are necessary to clarify the bypass grafting of the SC to muscle groups distal to the complete SCI to restore locomotion.- - - - - - - - - - ranking = 0.7188072084299keywords = paralysis (Clic here for more details about this article) |
10/25. Real-time measurement of frozen gait in patient with parkinsonism using a sensor-controlled walker.patients with Parkinson's disease develop gait disturbances. Although the use of walkers is very effective for maintaining locomotive ability, patients who have symptoms such as frozen gait (FG) and festinating gait may fall even with a walker equipped with a brake as they cannot use the brake well in an emergency and fail to follow the accelerating walker. None of the studies on walking aids to date have addressed real-time detection of FG or the use of this information for the control of the walking aid, monitoring of the state of improvement in the ambulatory function, or evaluation of the effect of the use of a walker. In this study, we evaluated whether the state called FG, a characteristic symptom of Parkinson's disease, can be detected by the use of a sensor-controlled walker with heel-to-toe pressure sensors. The following two measurements were carried out in one male healthy and a one male patient with stage 3 Parkinson's disease by the Hoehn-Yahr scale showing mild muscle rigidity, hypokinesia, and FG. In the healthy subject, the heel-to-toe pressure showed smooth heel-to-toe shifts during the standing phase. In the patient with Parkinson's disease, the heel-to-toe response time was about 2.4 times longer than in the healthy subject at the beginning of walking, and FG could be recorded as the difficulty in lifting the foot by the toes. Also, when FG was observed during walking, the pressure waves recorded by the same sensors showed two peaks occurring at short interval, indicating double landings.- - - - - - - - - - ranking = 23930.693824903keywords = parkinson, parkinsonism (Clic here for more details about this article) |
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