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| MS in focus Issue
12
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2008
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Thomas McNalley, MD, MA, Acting Assistant Professor and Jodie Haslekorn, MD, MPH, Director MS Center of Excellence West, Veterans Health Administration and Professor, Rehabilitation Medicine at the University of Washington, Seattle, ashington, USA |
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 The most important principle of treating spasticity is to develop reasonable and flexible goals that target specific manifestations of spasticity – pain, fatigue, stiffness or weakness – and, together with the person with MS, frequently reassess the effectiveness of treatments.
Spasticity can affect just a few parts of the body (focal spasticity), or it can manifest in multiple places (generalised spasticity). It can range from insignificant to incapacitating, with many levels in between. Spasticity can also increase and decrease.
Many people with MS recognise increased spasticity as a sign of a bladder or other infection, or of the increase in core body temperature that is associated with a fever or excessive exercise, or of a full bladder or colon.
Other causes of increased spasticity include:
- noxious stimuli such as a skin lesion
- a bladder or kidney stone
- fractures
- tight clothing
- menstruation
- psychological stress
- extreme environmental temperature
- hunger
- an MS exacerbation
- treatment with some disease modifying or antidepressant pharmaceutical agents.
It is important that people with MS and their healthcare team examine reasons why spasticity may suddenly increase and address them appropriately.
If there are no recent changes in health that could explain an increase in spasticity, then it is reasonable to think about different approaches to managing spasticity and this does not necessarily mean medication. Often the simplest way for many to reduce muscle tightness and soreness is with rangeof-motion exercises and stretching. Maintaining range of motion can be done with a regular home exercise programme, home physical therapy programme or through a community-based exercise class. Ice has also been shown to reduce spasticity in some studies, and the application of local heat can aid in stretching, although there is a lack of consensus about how often and long to stretch.
Oral medications
A number of medications have been used to treat generalised spasticity. Although there is variability in response to and tolerability of different medications, most practitioners will suggest baclofen as a firstline agent. It works at the level of the spinal cord to help the body inhibit muscle movement. A number of studies have shown that baclofen is effective in reducing pain, improving gait and overall function, as well as decreasing spasm frequency.
However, baclofen can cause fatigue, dry mouth, dizziness and nausea and many people start on baclofen and say it doesn’t work for them. However, if assessed carefully and consideration is given to dose and timing, the results may be more positive. A written regime, with slowly increasing doses that help a person with MS assess how baclofen affects them over a period of time, and regular review can make the use of baclofen much more successful. Even so, some people with MS still find they cannot tolerate the dose of baclofen required for efficacy because of the side effects.
Another medication clinicians frequently prescribe is tizanidine. Again starting at a low dose, tizanidine appears to be particularly effective for painful spasms at night. Like baclofen, it can cause sleepiness, dry mouth, dizziness and fatigue.
Diazepam is also effective in treating spasticity in some people. It appears to have a greater risk of causing sleepiness and muscle weakness, and it has the potential for dependence and addiction which can affect adherence.
Dantrolene can be used for spasticity and it works at the level of the muscles to limit contractions.
Besides sharing most of the side-effects of diazepam, baclofen and tizanidine, dantrolene also requires frequent laboratory monitoring to ensure the medication does not damage the liver. As a result, dantrolene is not prescribed as frequently as the other medications.
Other medications that may be prescribed include clonazepam and gabapentin, although again, side effects can be problematic.
A combination of therapies may also be helpful for some people, and this approach has become increasingly utilised by clinicians.
Local treatments for spasticity
For those with spasticity affecting a small area (focal spasticity), or who do not get relief from oral medications, local injections of botulinum toxin or phenol into the muscles can improve quality of life.
A typical example of spasticity treatable with botulinum toxin would be the overactivity of muscles that flex the wrist, reducing the ability to reach and grasp objects. Making those muscles weaker can improve both function and pain. There are two types of botulinum toxin, type A, known as Botox® in the United States and Dysport® in Europe; and type B, Myoblock®. A local injection of botulinim toxin can last 3–6 months and make functional activities easier to undertake.
Phenol or alcohol blocks are done less frequently, and involve identifying a point where nerve and muscle meet. Phenol is injected to destroy the nerve endings in that area only.
With both phenol and botulinum toxin, the effects are temporary and may require frequent injections. Also, individuals can build up antibodies to the botulinum toxin over time, making it ineffective. Some people are able to switch from the type A toxin to type B to prolong the therapeutic effect. The most appropriate treatment plan usually includes work with a physical and/or occupational therapist after the injection to improve functional movement of the affected area.
Surgery for spasticity
Orthopaedic surgeons and neurosurgeons might get involved in the management of spasticity in two ways. If a person experiences spasticity that has caused permanent deformity, a surgeon can lengthen tendons or fuse joints or otherwise address malformations. Surgical correction of deformity coupled with proper rehabilitation interventions can prolong sitting times in a chair, prevent skin breakdown or its recurrence, and reduce pain.
Surgeons can also contribute to the care of a person with MS who is a candidate for intrathecal baclofen therapy (ITB). Generally reserved for those who have lower extremity spasticity and do not have an adequate response to medication or who are unable to tolerate them, ITB involves the placement of a catheter into the thecal sac, a space around the spinal cord. The catheter connects to a reservoir and pump that has been placed under the abdominal skin. The pump delivers medicine directly to the spinal cord, which for most people provides relief from spasticity without the side effects caused by the oral form of baclofen, such as fatigue and drowsiness.
ITB involves the placement of a pump under the abdominal skin and a catheter into the thecal sac.
Although ITB was originally used primarily in people with severe spasticity who could no longer walk, it is now also used to help improve walking in some people with MS. Evaluation for this kind of intervention should, ideally, take place at an MS centre or a clinic where experienced providers and therapists can make initial assessments, trial test doses and adjust for the best functional outcomes. If a person with MS and the healthcare team decide to investigate the value of an ITB, the person will first be given a test dose of the medication via a lumbar puncture to gauge response. With an appropriate response, the person will be scheduled for surgery to permanently implant the pump and the catheter. The medication will be titrated for best effect. Refills are done by subcutaneous injection into the pumps port. The frequency of refills ranges from monthly to twice a year, depending on the dose necessary to achieve an optimal effect and the size of the pump reservoir.
Pumps can remain in place for 5–7 years, at which time the batteries wear out and need replacement.
It’s important to note that any abrupt withdrawal of baclofen therapy, oral or intrathecal, can lead to seizures. Those who are considering ITB should know the warning signs of a low or leaking reservoir. Oral baclofen doses similarly need to decrease under expert medical supervision.
Optimising management of spasticity can have a dramatic impact on the quality of life of people with MS, through a reduction of pain, weakness and muscle inefficiency. If a person with MS has troubling spasticity, working with the healthcare team to identify clear goals for treatment, adjusting treatments as needed, and understanding that spasticity will probably change over time will set the stage for the most effective interventions and the most satisfactory outcomes.
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