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Query: UMLS:C0026838 (spasticity)
 6,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A review is presented of current information about the structural and functional details of the muscle spindle, denervation supersensitivity, neurotrophism, regenerative capabilities of the peripheral and central nervous systems, CNS plasticity as revealed by recovery of function following brain lesions, and the secondary functional consequences of long-term spasticity. If this recent basic information is to have any practical impact, it must ultimately be incorporated into our concepts of spasticity and applied to our clinical evaluation and treatment procedures.
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PMID:Spasticity: its physiology and management. Part II. Neurophysiology of spasticity: current concepts. 13 21

Selected neurophysiologic studies can supplement clinical examination in assessing residual motor function after spinal cord or head injury. The ability of polyelectromyographic recording to detect subclinical suprasegmental control is illustrated in paraplegic patients after spinal cord injury. Excitatory or inhibitory modulation of segmental motor activity in a subpopulation of patients with clinically complete motor paralysis suggests residual connection across the lesion. This observation is consistent with the pathologic finding that complete transection of the spinal cord is rare after spinal cord injury. A preliminary study of motor-evoked potentials also indicates their potential value as an objective measure of the functional status of descending pathways. Neurophysiological assessment of subclinical residual motor function may be useful in understanding the role of suprasegmental input in the manifestation of spasticity, in objectively documenting recovery of function after injury, and may aid in the development of more specific restorative measures. Our limited experience in head-injured patients also suggests the potential usefulness of these tools in supplementing clinical evaluation.
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PMID:Neurophysiological assessment of spinal cord and head injury. 158 19

Twenty-five brain-injured adults who were treated for tardy ulnar neuropathy during a 5-year period were studied. Two patients had bilateral involvement. The incidence of late ulnar neuropathy in this population was determined to be 2.5%. The ulnar neuropathy was always on the neurologically impaired side and associated with significant spasticity. Diagnosis was made when intrinsic atrophy was noted in the hand. No patient initiated a subjective complaint. Nerve conduction velocity measurements confirmed impingement of the ulnar nerve in the cubital canal in 16 cases. Twenty-one of the 27 (78%) elbows had moderate to severe heterotopic ossification causing impingement of the ulnar nerve. All patients were treated by anterior transposition of the ulnar nerve. Follow-up averaged 22.7 months. Twenty-three (85%) extremities had complete recovery of ulnar nerve function. Four patients had improved but incomplete recovery of function. Prolonged compression of the nerve led to incomplete recovery.
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PMID:Late ulnar neuropathy in the brain-injured adult. 312 57

A 32-year-old woman experienced subacute onset of weakness in her left leg, urinary retention and difficulty in extending her right middle and third finger. She subsequently suffered episodes of myelopathy, optic neuritis and cerebellar ataxia over a period of several years. Brain MRI showed multiple areas of high signal intensity on T2-weighted images, consistent with multiple sclerosis (MS). However spinal MRI revealed no abnormal findings. In her most recent episode, at age 40 she developed paraparesis. Neurologic examination revealed down beat nystagmus on gazing to the right, horizontal jerk nystagmus gazing to the left, weakness of the right middle and third fingers and paraparesis associated with spasticity of the right leg. Sensory disturbance below C3 and diminished vibration and position sense in both legs were also observed. The patient could not stand or walk, and urinary disturbance was present. Spinal MRI revealed syrinx formation at the level of vertebral bodies C2 to C6. The syrinx within the cervical cord diminished in size after four months, but the patient was unable to walk unaided and had moderate sensory disturbance as before. This finding suggests that the prognosis of MS with syrinx formation following repeated episodes of myelopathy is not always favorable. We believe that functional recovery in MS with syringomyelia is affected by the severity of the demyelination and/or gliosis caused by MS rather than by the presence of the syrinx.
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PMID:[Multiple sclerosis with syringomyelia--case report]. 813 3

Sixty-seven patients were treated for Pott's paraplegia: 58 were adults and 9 were children. Sixty-four patients had active disease, and 3 had healed disease. All patients had triple chemotherapy with or without decompression surgery. Thirteen patients, including 9 children, were treated conservatively, whereas 54 patients who met the selection criteria for surgery were treated surgically. Fifty-two patients had anterior radical decompression surgery, and for 14 of them, anterior surgery was preceded by posterior instrumental stabilization surgery. Two patients with healed disease had posterior decompressive corpectomy. There was functional recovery in 60 (89.6%) patients, including 13 who had active disease that was treated conservatively. In 47 of the 54 surgically treated patients there was neurologic recovery, and 2 of these recovered incompletely with some residual spasticity. In the remaining 7 patients, there was no recovery. It took 2 to 6 months for recovery for the patients with conservative treatment, whereas it took <2 months for the patients with anterior decompression. The patients who had the combined 2-stage procedure could be mobilized earlier after neurologic recovery than could the patients having the anterior radical surgery and the conservatively treated patients. It was proven that paraplegia of active disease can be treated successfully by conservative or surgical means and that paraplegia caused by healing of fibrosis in the severely deformed spine was difficult to treat successfully, even with radical surgery.
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PMID:Pott's Paraplegia--67 cases. 862 69

The use of a functional neuromuscular stimulation (FNS) device can have therapeutic effects that persist when the device is not in use. Clinicians have reported changes in both voluntary and electrically assisted neuromuscular function and improvements in the condition of soft tissue. Motor recovery has been observed in people with incomplete spinal cord injury, stroke, or traumatic brain injury after the use of motor prostheses. Improvement in voluntary dorsiflexion and overall gait pattern has been reported both in the short term (several hours) and permanently. Electrical stimulation of skin over flexor muscles in the upper limb produced substantial reductions for up to 1 h in the severity of spasticity in brain-injured subjects, as measured by the change in torque generation during ramp-and-hold muscle stretch. There was typically an aggravation of the severity of spasticity when surface stimulation reached intensities sufficient to also excite muscle. Animals were trained to alter the size of the H-reflex to obtain a reward. The plasticity that underlies this operantly conditioned H-reflex change includes changes in the spinal cord itself. Comparable changes appear to occur with acquisition of certain motor skills. Current studies are exploring such changes in humans and animals with spinal cord injuries with the goal of using conditioning methods to assess function after injury and to promote and guide recovery of function. A better understanding of the mechanisms of neural plasticity, achieved through human and animal studies, may help us to design and implement FNS systems that have the potential to produce beneficial changes in the subject's central nervous systems.
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PMID:Therapeutic neural effects of electrical stimulation. 897 48

Functional restitution following spinal cord implantation of avulsed ventral roots was assessed electromyographically and correlated with the morphology of the regenerated neural structures in primates. The C5-C8 ventral roots were avulsed from the spinal cord in seven Macaca fascicularis monkeys. In three animals the roots were immediately reimplanted into the ventrolateral part of the spinal cord. In two monkeys the avulsed roots were reimplanted with a delay of 2 months and in two control animals the roots were not reimplanted. There was substantial recovery of function after both immediate and delayed spinal cord implantation of the avulsed ventral roots. The population of neurons that had regenerated was larger than on the control side, indicating a rescue of cells after an immediate root implantation. Different functional types of neurons had been attracted to regrow axons to the implanted root as judged by their position in the ventral horn. Thus, neurons normally supplying antagonistic muscles, such as the triceps muscle, participated in the innervation of the biceps muscle. Functionally this deficient directional specificity was correlated to both spasticity and co-contractions among agonistic and antagonistic muscles. Occasional electromyographic signs of function occurred also in control animals where the avulsed roots had not been implanted. This recovery was found to depend on regrowth from the site of avulsion, within the pia mater among the leptomeningeal cells and to the avulsed roots. The acceptable functional dexterity regained due to corrective surgery is discussed in terms of neurotrophism and plasticity.
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PMID:Spinal cord implantation of avulsed ventral roots in primates; correlation between restored motor function and morphology. 998 36

Assuming that neural regeneration after spinal cord injury (SCI) will eventually become a clinical reality, functional recovery will probably remain incomplete. Assistive devices will therefore continue to play an important role in rehabilitation. Neural prostheses (NPs) are assistive devices that restore functions lost as a result of neural damage. NPs electrically stimulate nerves and are either external or implanted devices. Surface stimulators for muscle exercise are now commonplace in rehabilitation clinics and many homes. Regarding implantable NPs, since 1963 over 40 000 have been implanted to restore hearing, bladder control and respiration. Epidural spinal cord stimulators and deep brain stimulators are routinely implanted to control pain, spasticity, tremor and rigidity. Implantable NPs have also been developed to restore limb movements using electrodes tunnelled under the skin to muscles and nerves. Spinal cord microstimulation (SC[mu]stim) is under study as an alternative way of restoring movement and bladder control. Improvement in bladder and bowel function is a high priority for many SCI people. Sacral root stimulation to elicit bladder contraction is the current NP approach, but this usually requires dorsal rhizotomies to reduce reflex contractions of the external urethral sphincter. It is possible that the spinal centres coordinating the bladder-sphincter synergy could be activated with SC[mu]stim. Given the large and growing number of NPs in use or development, it is surprising how little is known about their long-term interactions with the nervous system. Physiological research will play an important role in elucidating the mechanisms underlying these interactions.
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PMID:Neural prostheses. 1135 Oct 18

Severely brain-injured patients often suffer from disabilities and psycho-social handicaps. Early rehabilitation aims at improving their motor and functional recovery while preventing or treating complications as soon as possible. In this review we look at some issues encountered in early rehabilitation. We illustrate our discussion with data from 876 French traumatic brain injury patients admitted over the course of 1 year at 18 rehabilitation units that were asked for details of their current practice. Preservation of vital functions follows standardized protocols, but rehabilitation is more controversial. Few controlled trials are available. Good agreement exists among clinicians about prevention of orthopedic complications and treatment for spasticity. However, little consensus exists concerning treatment of non-pyramidal hypertonia and spasms or about procedures that can be undertaken to improve arousal from a coma or vegetative state. Finally, we look at other specific issues of early rehabilitation, namely prediction of outcome, psychological difficulties of patients and their families, efficiency and cost-effectiveness.
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PMID:Early rehabilitation after severe brain injury: a French perspective. 1148 56

Paralysis, muscle shortening, and muscle overactivity are the three main disabling factors in patients with spasticity. Occurring after most central lesions, muscle overactivity and shortening are not equally spread throughout all muscles of the body. In an agonist-antagonist couple, there is invariably "greater" overactivity and shortening of one versus the other. This is the rationale for the use of targeted local treatments that train the weaker agonist and stretch and partially block the more overactive and shorter antagonist. Central paralysis, muscle shortening, and muscle overactivity are intertwined, and the three corresponding therapies, motor training, stretch, and local partial blocks, should be implemented in combination. This triple treatment is the main condition for any functional recovery. Muscle shortening occurs acutely after a central nervous system lesion; therefore its treatment should be implemented as rapidly as possible.
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PMID:Pathophysiology of impairment in patients with spasticity and use of stretch as a treatment of spastic hypertonia. 1172 64


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