Treatment options for spasticity in children

Partial dorsal root rhizotomy and intrathecal administration of baclofen are two modalities used to treat spasticity in children. Each has its own inclusion criteria and mechanism of action. Both have been proven to relieve spasticity, and both have their particular side effects and complications. Programmable pumps for the accurate and reliable administration of intrathecal baclofen are expensive and demand a lifelong commitment to medication refill and hardware reimplantation. Partial dorsal root rhizotomy is a one-time surgical procedure, which differs from one center to another. It requires a team approach for patient selection and to determine whether other treatment options should take precedence. It also requires a period of postoperative reeducation in the form of physiotherapy. While some centers use intraoperative nerve root stimulation and muscle response recording as a guidance tool for rootlet sectioning, others claim equally good results without the added time-consuming technology.

     

Neurosurgical treatment of spasticity: indications in children

Today, we have several efficient neurosurgical treatments of spasticity in children with cerebral palsy. A good indication is possible only if a consensus about the goal of the surgery is found between the surgeon, the child and his/her family, and the reeducation team. This goal is not always functional. Clinical examination is not limited to the analytical assessment of spasticity, but must take into account the general and orthopedic state of the child, and his/her functional evolution, cognitive abilities, habits and general environment. The struggle against spasticity is part of a therapeutical programme which extends over several years. It must be considered before muscular contractures. On lower limbs, in the cases of general spasticity, we propose posterior rhizotomy or intrathecal baclofen administration. Posterior rhizotomy is proposed when a more aggressive intervention is preferred for some muscular groups or when the child's general environment does not allow for the medical care imposed by intrathecal administration. In the case of localized spasticity, botulinum toxin injection permits delaying until the child reaches the age for selective neurotomy. On upper limbs, in children with quadriplegia the indication is essentially physical and occupational therapy. We cannot count on the positive side effects of rhizotomy or intrathecal administration of baclofen on the upper limbs. In children with hemiplegia, with localized or global spasticity of the upper limb, botulinum toxin is proposed as the first form of treatment. Neurotomy or rhizotomy can follow toxin, according to the efficacy of the toxin.     

Neurosurgical treatment of spasticity: selective posterior rhizotomy and intrathecal baclofen.

The pathophysiology of spasticity and the history of posterior rhizotomies are reviewed. The rationale for selective posterior rhizotomies is that electrical stimulation identifies afferent posterior rootlets that terminate on relatively uninhibited alpha motoneurons; if these uninhibited rootlets are divided, spasticity can be alleviated without loss of other posterior root functions. Indications, technique, and results of selective posterior rhizotomies are presented. The use of continuous intrathecal baclofen (CITB) is summarized. CITB at doses of approximately 300 micrograms/day consistently reduces lower extremity spasticity and diminishes or alleviates muscle spasms in adults with spasticity of spinal origin. Single doses of intrathecal baclofen significantly decrease lower extremity muscle tone in children with cerebral palsy, and the effects can be maintained in these patients by CITB infusions which diminish muscle tone not only in the lower extremities, but in the upper extremities as well. CITB is best accomplished via an externally programmable pump that allows titration of the daily dose to attain the desired reduction in spasticity. Factors influencing the decision for rhizotomy or CITB are presented.     

Prevention of severe contractures might replace multilevel surgery in cerebral palsy: results of a population-based health care programme and new techniques to reduce spasticity

During the 1990s three new techniques to reduce spasticity and dystonia in children with cerebral palsy (CP) were introduced in southern Sweden: selective dorsal rhizotomy, continuous intrathecal baclofen infusion and botulinum toxin treatment. In 1994 a CP register and a health care programme, aimed to prevent hip dislocation and severe contractures, were initiated in the area. The total population of children with CP born 1990-1991, 1992-1993 and 1994-1995 was evaluated and compared at 8 years of age. In non-ambulant children the passive range of motion in hip, knee and ankle improved significantly from the first to the later age groups. Ambulant children had similar range of motion in the three age groups, with almost no severe contractures. The proportion of children treated with orthopaedic surgery for contracture or skeletal torsion deformity decreased from 40 to 15% (P = 0.0019). One-fifth of the children with spastic diplegia had been treated with selective dorsal rhizotomy. One-third of the children born 1994-1995 had been treated with botulinum toxin before 8 years of age. With early treatment of spasticity, early non-operative treatment of contracture and prevention of hip dislocation, the need for orthopaedic surgery for contracture or torsion deformity is reduced, and the need for multilevel procedures seems to be eliminated.     

Implantable baclofen pump as an adjuvant in treatment of pressure sores

Currently, the success of ulcer treatment is limited by the high recurrence and complication rates. Spasticity is an important contributing factor to ulcer recurrence, and intrathecal baclofen is an effective method to reduce spasticity. Spasticity creates friction, shear, and mobility impairment resulting in wound dehiscence, flap loss, infection, and hematoma. Spasticity can be managed pharmacologically and surgically; baclofen is the drug of choice. Baclofen inhibits spasticity by blocking excitatory neurotransmitters in the spinal dorsal horn. Intrathecal baclofen maximizes the dose delivered to spinal receptors and minimizes the side effects associated with oral baclofen. Case reports of intrathecal baclofen used in patients with pressure sores demonstrate the use of intrathecal baclofen to improve reconstructive outcomes in spastic patients.     

Efficacy of dorsal longitudinal myelotomy in treating spinal spasticity: a review of 20 cases

The authors report their experience using dorsal longitudinal myelotomy in treating spasticity in 20 patients with complete spinal cord injuries. These patients suffered from severe painful flexor/extensor spasms that prevented them from wheelchair ambulation and/or their decubitus ulcers healing. All were receiving large doses of various oral drugs, including baclofen, which had failed to control their spasticity, and all underwent a modification of a posterior T-myelotomy as first described by Bischof. All 20 patients enjoyed immediate complete relief of their painful spasms, although two (10%) eventually experienced return of their spasms and are thus classified as long-term failures. Seventeen patients succeeded in markedly reducing, or being completely weaned from, their antispasmodic medications. In 11 of 14 patients, nonhealing decubitus ulcers subsequently healed with treatment. Bladder function was unchanged from the preoperative status in all patients. Chronic intrathecal baclofen infusion has recently been reported as an effective treatment of the spasticity of paraplegia. The results of this study, along with previous reports advocating dorsal longitudinal myelotomy, suggest that this approach is an efficacious alternative to chronic baclofen infusion in reducing spasticity for complete paraplegics. Considering the cost of the infusion pump, along with the fact that chronic intrathecal baclofen therapy necessitates long-term medical supervision, it appears that myelotomy is superior for this select group of patients who have no hope of regaining voluntary motor function.     

Neurosurgery for spasticity

Spasticity is usually a useful substitute for deficiency of motor strength. However not infrequently, it may become harmful leading to an aggravation of motor disability. When excessive spasticity is not sufficiently controlled by physical therapy and pharmacological treatment, patients can have recourse to neurosurgery: neurostimulation, intrathecal baclofen or selective ablative procedures. Because excessive hypertonia has to be reduced without suppression of the useful muscular tone or impairment in the residual motor and sensory functions, neuroablative procedures must be as selective as possible. These selective lesions can be performed at the level of peripheral nerves, spinal roots, spinal cord, or the dorsal root entry zone (DREZ lesions).     

Treatment of spasticity in a spinal cord-injured patient with intrathecal morphine due to intrathecal baclofen tolerance--a case report and review of literature

STUDY DESIGN: Case report. OBJECTIVE: To report treatment of spasticity in a spinal cord-injured person with intrathecal morphine after the person developed tolerance to intrathecal baclofen. METHOD: Spasticity in a 36-year-old man with T6 complete paraplegia was treated with increasing doses of intrathecal baclofen. When he developed tolerance to intrathecal baclofen, he was given continuous infusion of morphine intrathecally. SETTING: Regional Spinal Injuries Centre, UK. RESULTS: Spasticity was adequately controlled by intrathecal morphine. CONCLUSION: In spinal cord-injured patients with severe spasticity, who become tolerant to intrathecal baclofen, treatment with intrathecal morphine may be useful.     

Continuous intrathecal infusion of baclofen in patients with spasticity caused by spinal cord injuries

The aim of this study was to determine the efficacy and safety of intrathecal baclofen therapy delivered by a programmable pump for the chronic treatment of spinal spasticity. Twelve patients with intractable spasticity caused by spinal cord injuries underwent implantation of a programmable continuous infusion pump after significant reduction in spasticity following an intrathecal test bolus of baclofen. No deaths or new permanent neurological deficits occurred following surgery or chronic intrathecal baclofen therapy. The follow-up (12 months) shows a reduction in rigidity in the lower limb of 2.0 points on the Ashworth scale and in the upper limb of 1.2 points. Muscle spasms were reduced from a mean preoperative score of 2.8 to a mean postoperative score of 1.0. In two cases, we observed postoperative catheter dislocation, a complication which could be corrected surgically. This study demonstrates that chronic intrathecal baclofen infusion is a safe and effective form of treatment of intractable spasticity in patients with spinal cord injury. There is considerable reduction in the risk of infection in view of the fact that interrogation and programming of the implanted programmed pumps is noninvasive. Electronic Publication     

Rapid progression of scoliosis following insertion of intrathecal baclofen pump

Placement of an intrathecal baclofen pump is a common treatment of spasticity in cerebral palsy patients. Though effective, the hardware is prone to malfunction, and multiple revisions are often necessary. Additional complications have also been described, including infection and drug toxicity or withdrawal. The authors report another complication of intrathecal baclofen therapy: accelerated progression of scoliosis after pump insertion. A retrospective chart review was performed on four patients who showed accelerated scoliotic progression after intrathecal baclofen pump insertion for treatment of spasticity. Cobb angles were measured from preoperative and postoperative radiographs to determine the rate of scoliotic degeneration both before and after pump insertion. Although there may not be a direct correlation between intrathecal baclofen and scoliosis, the authors consider the issue important enough to warrant discussion with any patient considering intrathecal baclofen.     

Intrathecal baclofen. Experimental and pharmacokinetic studies

Baclofen, the most effective drug to treat spasticity, is a specific agonist of gamma-aminobutyric acid-B receptors, and is very abondant in the superficial layers of the spinal cord. Given orally, baclofen does not easily penetrate the blood-barrier, and is distributed equally to the brain and spinal cord. After oral administration of baclofen, the drug is resorbed by more than 80-90% in the stomach and bowel and is eliminated by urinary excretion. Failure of oral medication to produce sufficient relief of spasticity is due to the poor passage of the drug across the blood-brain barrier. In animals the concentration in brain is less than 1/10 of the blood levels. The problem of insufficient anti-spastic efficacy (in relation to the rate of side-effects) after systemic medication may be overcome by local application in spinal CSF. Direct intrathecal administration of baclofen in the treatment of severe spasticity was proposed in 1984 by Richard Penn with the objective to carry out a selective spinal distribution of the active principle thus avoiding supraspinal side effects. The pharmacokinetics of baclofen in animal and man after intrathecal administration have been investigated to determine the CSF pharmacokinetic parameters.     

Measurement of peripheral muscle resistance in rats with chronic ischemia-induced paraplegia or morphine-induced rigidity using a semi-automated computer-controlled muscle resistance meter

In experimental and clinical studies, an objective assessment of peripheral muscle resistance represents one of the key elements in determining the efficacy of therapeutic manipulations (e.g. pharmacological, surgical) aimed to ameliorate clinical signs of spasticity and/or rigidity. In the present study, we characterize a newly developed limb flexion resistance meter which permits a semi-automated, computer-controlled measurement of peripheral muscle resistance (PMR) in the lower extremities during a forced flexion of the ankle in the awake rat. Ischemic paraplegia was induced in Sprague-Dawley rats by transient aortic occlusion (10 min) in combination with systemic hypotension (40 mm Hg). After ischemia the presence of spasticity component was determined by the presence of an exaggerated EMG activity recorded from gastrocnemius muscle after nociceptive or proprioceptive afferent activation and by velocity-dependent increase in muscle resistance. Rigidity was induced by high dose (30 mg/kg, i.p.) of morphine. Animals with defined ischemic spasticity or morphine-induced rigidity were then placed into a plastic restrainer and a hind paw attached by a tape to a metal plate driven by a computer-controlled stepping motor equipped with a resistance transducer. The resistance of the ankle to rotation was measured under several testing paradigms: (i) variable degree of ankle flexion (40 degrees, 50 degrees, and 60 degrees), (ii) variable speed/rate of ankle flexion (2, 3, and 4 sec), (iii) the effect of inhalation anesthesia, (iv) the effect of intrathecal baclofen, (v) the effect of dorsal L2-L5 rhizotomy, or (vi) systemic naloxone treatment. In animals with ischemic paraplegia an increased EMG response after peripheral nociceptive or proprioceptive activation was measured. In control animals average muscle resistance was 78 mN and was significantly increased in animals with ischemic spasticity (981-7900 mN). In ischemic-spastic animals a significant increase in measured muscle resistance was seen after increased velocity (4 > 3 > 2 sec) and the angle (40 degrees > 50 degrees > 60 degrees) of the ankle rotation. In spastic animals, deep halothane anesthesia, intrathecal baclofen or dorsal rhizotomy decreased muscle resistance to 39-80% of pretreatment values. Systemic treatment with morphine induced muscle rigidity and corresponding increase in muscle resistance. Morphine-induced increase in muscle resistance was independent on the velocity of the ankle rotation and was reversed by naloxone. These data show that by using this system it is possible to objectively measure the degree of peripheral muscle resistance. The use of this system may represent a simple and effective experimental tool in screening new pharmacological compounds and/or surgical manipulations targeted to modulate spasticity and/or rigidity after a variety of neurological disorders such as spinal cord traumatic or ischemic injury, multiple sclerosis, cerebral palsy, or Parkinson's disease.     

Functional benefits and cost/benefit analysis of continuous intrathecal baclofen infusion for the management of severe spasticity

OBJECT: Intrathecally delivered baclofen has been used as a treatment for severe spasticity since 1984. Despite this, there are uncertainties surrounding the benefits of treatment and the costs involved. The authors assessed the evidence of benefits and identified costs and the cost/benefit ratio for continuous intrathecal baclofen infusion in the treatment of severe spasticity. METHODS: A systematic literature review was conducted to estimate the effect of continuous intrathecal baclofen infusion on function and quality-of-life (QOL) measures in patients with severe spasticity. Outcomes were related to standard QOL scores to estimate potential gains in quality-adjusted life years (QALYs). Information on the costs of continuous intrathecal baclofen infusion was obtained from hospitals in the United Kingdom. This information was combined to estimate the cost/benefit ratio for the use of continuous intrathecal baclofen infusion in patients with different levels of disability from severe spasticity. Studies indicate that bedbound patients are likely to improve their mobility and become able to sit out of bed. Patients with severe spasm-related pain are likely to have major improvement or complete resolution of this pain. Many other benefits are also reported. Such benefits are related to costs per QALY in the range of 6,900 pounds to 12,800 pounds ($10,550-$19,570 US). CONCLUSIONS: In carefully selected patients who have not responded to less invasive treatments, continuous intrathecal baclofen infusion is likely to lead to worthwhile functional benefits. Continuous intrathecal baclofen infusion has an acceptable cost/benefit ratio compared with other interventions that are funded by the health service.     

Treatment of cerebral origin spasticity with continuous intrathecal baclofen delivered via an implantable pump: long-term follow-up review of 18 patients.

OBJECT: The goal of this study was to assess the long-term benefits of managing severe spasticity by using continuous infusion of intrathecal baclofen delivered via an implantable pump. METHODS: Eighteen patients with severe spasticity of cerebral origin, who failed to respond adequately to more conservative treatments, have-been treated with continuous infusion of intrathecal baclofen delivered via an implanted pump. Follow-up review of these patients has lasted between 12 months and 9 years. The patients have been assessed using a variety of tools. Seventeen have had a significant reduction in tone and all have benefited by a reduced need for nursing care or increased function or both. CONCLUSION: Long-term continuous infusion of intrathecal baclofen delivered via an implantable pump offers an effective method for dealing with otherwise intractable spasticity.     

Intrathecal baclofen for treatment of spasticity in patient with cerebral palsy--a preliminary report]

Spasticity is a common symptom of upper neuron damage which requires continuous research for new treatment strategies. The aim of this paper is to present the result of intrathecal baclofen infusion in treatment of spasticity in patients with cerebral palsy. Three patients (aged 16 to 21 years) in whom baclofen pumps were implanted underwent clinical and neurophysiological assessment both before and after pump implantation. Early results of spasticity treatment in cerebral palsy with intrathecal baclofen infusions are very promising.     

Successful intrathecal ethanol block for intractable spasticity of AIDS-related progressive multifocal leukoencephalopathy.

OBJECTIVE: To study the efficacy of intrathecal ethanol block to relieve intractable spasticity in AIDS-related progressive multifocal leukoencephalopathy (PML) when long-term intrathecal baclofen infusion cannot be used. METHODS: A 33-year-old man with AIDS-related PML developed very severe spastic paraparesis (Ashworth rigidity score, 4) and painful muscle spasms. The patient was unable to sit in his wheelchair and remained bed bound. Combined oral baclofen and tizanidine at therapeutical doses were used without any effect on the spasticity. The patient refused the placement of an intrathecal catheter for long-term baclofen infusion. A single intrathecal ethanol (6 ml) injection in the L2-L3 intervertebral space with the patient placed in a lateral Trendelenburg (40 C) position was performed. RESULTS: The procedure was very effective in improving the stiffness (Ashworth rigidity score. 2, after the technique) and the muscle spasms disappeared. No side effects during or after the injection were observed. CONCLUSION: Intrathecal ethanol block is a last but very useful choice for treatment of intractable spasticity in PML and other neurologic disorders in AIDS patients when other oral treatments have failed and intrathecal baclofen infusion is not suitable.     

Sexual dysfunction associated with intrathecal baclofen use: a report of two cases

BACKGROUND/OBJECTIVE: Intrathecal baclofen is considered standard treatment for severe spasticity of spinal cord and cerebral origin. Recognized side effects include fatigue and constipation. There are few reported findings of sexual dysfunction in men and none in women. METHODS: Two case reports. RESULTS: A male and a female patient with spasticity treated with intrathecal baclofen were recognized to have sexual dysfunction side effects from treatment. On reduction of the intrathecal baclofen dose, complete return to baseline sexual function was achieved for both subjects. CONCLUSIONS: Intrathecal baclofen can impair sexual function and ejaculation in some patients. Clinicians should be aware of this risk and ask about it during routine clinic follow-up for spasticity. Dosing adjustments need to be considered in these patients.     

How selective is selective posterior rhizotomy?

Although selective posterior rhizotomy has become an increasingly utilized surgical treatment for spasticity, the procedure is unstandardized and is performed differently at various medical centers. Most surgeons use some form of direct dorsal rootlet stimulation with intraoperative multichannel electromyographic response monitoring. Electrophysiological monitoring offers the theoretical advantage of identifying pathologic reflex circuits for interruption while preserving those pathways that are "normal." However, the monitoring technique most commonly used has not been critically evaluated and, therefore, its value remains uncertain. In 22 selective posterior rhizotomy procedures performed for spastic cerebral palsy, the authors were unable to identify a single electromyographic response that could be called normal by presently accepted criteria. Dorsal rootlets were chosen for division on the basis of relative degrees of abnormality. Intraoperative electromyographic monitoring of a nonspastic patient produced tracings suggestive of spasticity by presently accepted criteria. These discrepancies suggest that current electrophysiological monitoring in selective posterior rhizotomy should be reevaluated.     

Intrathecal baclofen for spasticity of spinal origin: seven years of experience.

A total of 66 consecutive patients with severe spasticity of spinal cord origin were screened with intrathecal baclofen, and all but two responded with a two-point decrease in their Ashworth spasticity scale and/or spasm scale score. Of these, 62 elected to receive chronic intrathecal baclofen administration by means of an implanted delivery system. These patients have been followed for an average of 30 months (the first three for 81 months). Intrathecal baclofen has been well tolerated and all serious side effects were transient and have been managed by dose adjustments. The pump presently available has worked safely; the only problem has been stalling in 7% of these devices. The catheter system has had to be repaired in just over one-half of the patients and is the main cause of interruption of drug delivery. Of the 62 patients implanted, 52 (84%) continue to be treated adequately for spasticity; there are three poor long-term responders, four deaths due to underlying disease, and three whose participation has been voluntarily withdrawn. It is suggested that long-term control of spinal spasticity by intrathecal baclofen can be achieved in most patients.