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

The neuropathology of the vegetative (VS) and minimally conscious (MCS) states and the pathophysiology of spasticity are reviewed. Current treatment options available in the physical management of children in a low-level state and factors influencing the physiotherapy treatment of children in a low-level state will be discussed. The complex neuropathology of VS and MCS helps to explain the varied clinical presentations of children in VS and MCS. Spasticity and muscle contracture are common motor sequelae of VS and MCS. Loss of inhibition by descending motor pathways is thought to result in increased muscle tone or spasticity. However, secondary changes in muscle fibre structure and periarticular connective tissue may be an additional component to increased muscle tone. A multimodal approach combining physical, pharmacological and surgical interventions is likely to be the most effective. Knowledge of the likelihood of recovery from VS and MCS can be helpful in determining the frequency and intensity of physiotherapy. Ethical issues in the management of children in a low-level state include a consideration of the benefits to the child and the child's family and the costs to the health care team and the medical institution.
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PMID:The vegetative and minimally conscious states in children: spasticity, muscle contracture and issues for physiotherapy treatment. 1187 15

Spasticity is only one of several components of the upper motor neurone (UMN) syndrome, known collectively as the 'positive' phenomena, that are characterized by muscle overactivity. Other components include tendon hyper-reflexia, clonus, the clasp-knife phenomenon, flexor and extensor spasms, a Babinski sign, and spastic dystonia. Spasticity is a form of hypertonia due to hyperexcitable tonic stretch reflexes. It is distinguished from rigidity by its dependence upon the speed of the muscle stretch and by the presence of other positive UMN signs. Hyperactive spinal reflexes mediate most of these positive phenomena, while others are due to disordered control of voluntary movement or abnormal efferent drive. An UMN lesion disturbs the balance of supraspinal inhibitory and excitatory inputs, producing a state of net disinhibition of the spinal reflexes. These include proprioceptive (stretch) and nociceptive (flexor withdrawal and extensor) reflexes. The clinical syndrome resulting from an UMN lesion depends more upon its location and extent, and the time since it occurred, than on the pathology of the lesion. However, the change in spinal reflex excitability cannot simply be due to an imbalance in supraspinal control. The delayed onset after the lesion and the frequent reduction in reflex excitability over time, suggests plasticity in the central nervous system. Knowledge of the electrophysiology and neurochemistry of spinal reflexes, together with the action of antispasticity drugs, helps us to understand the pathophysiology of spasticity.
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PMID:The pathophysiology of spasticity. 1191 43

Neurosurgery is only considered for severe spasticity following the failure of noninvasive management (adequate medical and physical therapy). The patients are carefully selected, based on rigorous multidisciplinary clinical assessment. In this we evaluate the contribution of the spasticity to the disability and any residual voluntary motor function. The goals for each patient are: (a) improvement of function and autonomy; (b) control of pain; and (c) prevention of orthopaedic disorders. To achieve these objectives, the surgical procedure must be selective and reduce the excessive hypertonia without suppressing useful muscle tone and limb functions. The surgical procedures are: (1) Classical neuro-ablative techniques (peripheral neurotomies, dorsal rhizotomies) and their modern modifications using microsurgery and intra-operative neural stimulation (dorsal root entry zone: DREZotomy). These techniques are destructive and irreversible, with the reduced muscle tone reflecting the nerve topography. It is mainly indicated when patients have localized spasticity without useful mobility. (2) Conservative techniques based on a neurophysiological control mechanism. These procedures are totally reversible. The methods involve chronic neurostimulation of the spinal cord or the cerebellum. There are only a few patients for whom this is indicated. Conversely, chronic intrathecal administration of baclofen, using an implantable pump, is well established in the treatment of diffuse spasticity of spinal origin. From reports in the literature, we critically review the respective indications in terms of function, clinical progression and the topographic extent of the spasticity.
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PMID:The surgical management of spasticity. 1191 48

Locomotor control requires a spatiotemporal coordination of passive and active forces across the movement system. Both anticipatory and reactive strategies operate in locomotor control. Mammalian locomotion is based on a rhythmic, "pacemaker" activity of spinal stepping generators. Reflex modification of the gait cycle is task-, context- and especially phase-dependent. In spasticity, together with disturbed supraspinal control, the phase-dependent reflex modulation of the gait cycle is severely impaired and there is altered modulation and timing of muscle activation and relaxation during voluntary movement. There is also a poor correlation between EMG activity and tension development in the spastic muscle. The tension increases without sufficient muscle activation and disconnection and dyscoordination between muscle activation, tension development and motor performance develops. The pattern of muscle activation and the development of increased muscle tone in patients with spasticity may be dramatically different in active movement from that observed in clinical testing of the passive muscles. Strategies used in the functional treatment of spasticity should be aimed at training and activating residual motor function, suppression of pathological and unfavourable movement and postural patterns and preventing secondary complications. In the 1990s a number of new specific instrumental methods and technical equipment supporting gait rehabilitation in patients with CNS lesions were developed: rhythmic auditory stimulation and other types of rhythmic stimulation, partial body support, usually with treadmill walking, complex orthotic support of bipedal locomotion, multichannel functional electrical stimulation, usually with programmable computer control, and advanced gait trainers. In therapy of spastic gait, the functional goals should be clearly determined from the kinesiological point of view of the impairment, and the impact on disability and handicap should be considered and a multidisciplinary approach is essential. (Ref. 139.)
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PMID:Clinical neurokinesiology of spastic gait. 1206 Oct 84

We sought markers for predicting a favorable outcome of botulinum toxin A injected to the lower-extremity muscles of 26 children with hemiplegic or diplegic cerebral palsy. Clinical assessment preceding and 1 month following injection included gross motor function measure, a modified Ashworth scale, and evaluation of range of motion of knee extension and ankle dorsiflexion. Response to treatment was classified based on a parent questionnaire. The 19 children (73%) considered by their parents as being good responders were compared to the 7 (27%) considered as being poor responders. In the good responders, the preinjection Ashworth scale (spasticity) was significantly higher (P < .05) and gross motor function measure scores (function) were lower (P < .05). Sixty-eight percent of the good responders were nonindependent walkers compared to 14% of the poor responders (P < .05). There were no differences in age, type of cerebral palsy, and dose of injection. An Ashworth scale indicating increased muscle tone, lower gross motor function measure scores, and nonindependent ambulatory status were predictive for a favorable response to botulinum toxin A injections and can guide patient selection and expectations of treatment outcome.
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PMID:Parameters for predicting favorable responses to botulinum toxin in children with cerebral palsy. 1208 83

Spasticity is common feature of human spinal cord injury. It contributes to motor impairment and it also promotes joint deformity in patients who have sustained such injury. The classical definition of spasticity highlights the increased resistance of a joint to externally imposed motion. This resistance is attributable largely to changes in stretch reflex excitability, and it is manifested primarily in those muscles being stretched by the motion. Under this definition, there would be little activity in muscles crossing other joints. In spinal cord injury, however, muscles innervated from distal spinal segments often exhibit little hypertonia, yet patients report the occurrence of disabling spasms. These spasms appear as coordinated patterns of muscle activation throughout the limb, involving either limb flexors or extensors. These patterns are therefore quite different from those of classical spasticity. The receptor origins and neural pathways responsible for the spasms in spinal cord injury will be addressed.
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PMID:Reflex mechanisms for motor impairment in spinal cord injury. 1217 Nov 26

New effective methods to reduce spasticity and dystonia are now included in the treatment of children with cerebral palsy (CP): selective dorsal rhizotomy (SDR), continuous intrathecal infusion of baclofen by an implanted pump or intramuscular injections of botulinumtoxin A. SDR is the only method that can reduce the spasticity permanently. Strong evidence exists for a positive impact of SDR on the function of the children. A multidisciplinary approach is required as it is essential to choose the best treatment for each child in each developmental period. In Lund physicians and physiotherapeuts from different disciplines such as paediatric orthopaedic surgery, neurosurgery and neurology form a central spasticity team which co-operates with the local child habilitation services. We have found that a common structured and standardized follow-up programme with early intervention against muscle hypertonia and imbalance can prevent hip luxation and contractures in children with CP.
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PMID:[New therapeutic methods for spasticity and dystonia in children with cerebral palsy require multidisciplinary team work. Comprehensive approach yields good results]. 1259 78

The history of neurosurgery for spasticity is strongly linked to the beginning of neurosurgery. With the discovery of the stretch reflex by Sherrington and the quality of the clinical studies at that time, especially the description of the different kinds of hypertonia by Babinski, the new surgeons of the nervous system started early with interruption procedures on dorsal roots (Foerster) or peripheral nerves (Lorenz, Stoffel). In France, this field of functional neurosurgery grew rapidly. Gros in Montpellier improved the technique of dorsal rhizotomy, while Sindou in Lyons, created the technique of drezotomy after studies on pain mechanisms. The history was then followed in Chicago by Penn and Kroin who developed the technique of intrathecal baclofen which indications are still increasing today. Improvement of knowledge on neurophysiology and control of movement lead to an optimisation of the surgical procedures where French speaking neurosurgery plays an important role.
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PMID:[History of neurosurgical treatment of spasticity]. 1274 88

Severe head injury can induce hypertonia. There are two kinds of hypertonia related to severe injury. The most common one is a spasticity that occurs a long time after the head injury; the second is hypertonia that occurs during the early stage of the post-trauma recovery. Hypertonia is associated with other symptoms and defines post-trauma dysautonomia. Intrathecal baclofen can alleviate spasticity in severe head injury with improvement of the Ashworth score, spasm score or reflex score. But it also improves the number of paroxymal dysautonomic episodes. Real functional improvement is more difficult to show. To be effective, intrathecal baclofen therapy in brain injured patients needs high doses per day, through a spinal catheter in the mediothoracic region, and delivered at least continuously for a few hours to achieve a functional improvement.
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PMID:[Intrathecal baclofen and traumatic brain injury. A review]. 1274 4

Neuromuscular blockade via injection of alcohol, phenol, or botulinum toxin reduces the tone of overactive muscles in order to restore the appropriate balance between agonists and antagonists. Such a restoration allows improved stretch and increased resting length and can reduce the likelihood of contracture. Alcohol or phenol, injected onto the motor nerve, denatures proteins and promotes axonal degeneration. The onset of action is within hours, whereas the duration of action is variable, ranging from 2 weeks to 6 months and beyond. The advantages of alcohol or phenol chemodenervation lie in their low cost and lack of antigenicity. The disadvantages include the technical difficulty of the injections and significant risk for pain as a result of treatment. Botulinum toxins, purified forms of Clostridium botulinum exotoxins, are injected directly into muscle, where they cleave one or more vesicle fusion proteins, thus blocking release of acetylcholine at the neuromuscular junction. Three commercial products--two of serotype A and one of B--are available. Each differs in its unit potency, side effects, and duration of action. On average, botulinum toxin has a clinical onset of action approximately 12 to 72 hours after injection, with a peak effect at 1 to 3 weeks. Effects then plateau for 1 to 2 months, with patients often requiring reinjection approximately every 3 months. Side effects may include local discomfort at the site of the injection and excessive weakness of the injected or nearby muscles, although more distant effects may occur. Antibody formation is a significant clinical concern and eventually obviates treatment benefit in approximately 5% of patients. Switching serotypes may be effective, at least temporarily. Consensus dosing guidelines have been developed and are presented within. Numerous studies have suggested that botulinum toxin has a role in the care of children with spasticity or dystonia related to cerebral palsy, and may improve equinus, gait, upper extremity use, comfort, and care. Evidence of functional improvement remains equivocal in the severely impaired child; however, there is evidence for improvement in less impaired children. The optimal candidate for injectable neuromuscular blockade is one who has a limited number of muscles that need treatment, who does not have fixed contracture, and who retains selective motor control. The ultimate goal of treatment for the hypertonic child is to maximize function, comfort, and independence. Hypertonia is only one aspect of the upper motoneuron syndrome, which includes both positive and negative symptoms. The treatment program, in which chemodenervation is only one tool, requires a multidisciplinary evaluation and individualized plan to address the whole patient.
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PMID:Injectable neuromuscular blockade in the treatment of spasticity and movement disorders. 1367 71


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