Intrathecal baclofen (ITB) is an invasive treatment for spasticity and spasms. It used to be thought of as a last resort but more recently both health professionals and people with MS are realising it can help to keep people mobile and well without the side effects often experienced by oral medications. Dr Val Stevenson discusses the treatment and Carmel Mackey, who uses a baclofen pump, talks about how it has affected her life
What is spasticity?
Spasticity means there is an increase in muscle tone. In other words, when the muscle is moved, there is more resistance to this movement than there normally would be. This stiffness can interfere with fine control causing a loss of fluidity of movement.
Spasms are also a common feature causing a limb to suddenly jerk out straight (extensor spasm), flex up towards the body (flexor) or cause the legs to come together (adductor). These spasms can be painful or even dangerous if they occur during transferring or walking.
Clonus or a repetitive tapping of the feet can also be a problem.
How common is spasticity?
Unfortunately spasticity and spasms are an extremely common and troublesome feature of living with MS. In a survey, 84% of 18,727 patients with MS reported at least some symptoms of spasticity, and 30% reported moderate to severe symptoms.
Does it always need treating?
Symptoms of spasticity can be unpleasant but sometimes it can actually be helpful; if a person's legs are very weak the stiffness spasticity causes may help in transferring from bed to chair or even in walking. However, even if this is the case, it is still important to see a physiotherapist to ensure movement patterns are optimal and to prevent complications such as contractures (shortening of muscles or permanent joint changes).
How can spasticity be treated?
The mainstay for managing spasticity is through physical measures. It is important to keep muscles, ligaments and joints as flexible as possible. A physiotherapist can advise on how to maintain flexibility, teach specific stretches and strengthening exercises and advise on different ways of moving and positioning the body.
It is also essential that the person with MS is knowledgeable about spasticity, its associated features and possible trigger factors. Urinary problems, constipation, skin breakdown, infection, inappropriate seating, ill fitting clothes or splints can all exacerbate spasticity or spasms. Attention to these may prevent the need to escalate drug treatments.
Sometimes however, exercise and managing trigger factors are not enough and drug treatments also need to be used.
Which drugs are used to treat spasticity?
Which drug is tried first depends on the specific problem and any other relevant features. For example general stiffness could be treated with baclofen first line, spasticity with associated neuropathic pain may respond well to gabapentin or pregabalin, nocturnal spasms disturbing sleep often respond very well to clonazepam.
Whichever drug is used first should be started at a low dose and slowly increased until the goal of treatment is reached. This may be improvement in walking or transfers, less pain or perhaps a good night's sleep. Unfortunately all of the drugs can cause side effects, the commonest of which are drowsiness and light headedness. If side effects are experienced before the goal is reached it may mean a second drug needs to be added in.
What if the tablets don't help?
If it is not possible to control the spasticity or spasms with these drugs without intolerable side effects, Sativex (cannabis extract spray) can be helpful. About half of people with MS and moderate to severe spasticity will respond to Sativex; whether someone is a responder can be identified after a four week trial of the drug. The dose is then controlled by varying the number of sprays taken each day. Sativex is usually prescribed by an MS or spasticity specialist who will monitor the effects over the trial period and then continue prescribing for those people who have responded. However access to Sativex is variable throughout the UK.
Intrathecal baclofen in multiple sclerosis
If spasticity and spasms continue to be a problem then intrathecal baclofen should be considered. Intrathecal refers to the space surrounding the spinal cord; this space is filled with cerebrospinal fluid (CSF). Delivering the baclofen into the CSF allows it to act directly on the nerve receptors of the spinal cord. This means tiny doses are used (approximately 100th of the oral dose), thus avoiding the commonly seen side effects of oral baclofen such as drowsiness.
The baclofen is delivered by an implanted pump in the lower abdomen; this is connected to the intrathecal space via a catheter (very thin tube) which runs under the skin round to the back and into the spine. Implantation requires an operation under general anaesthetic.
The use of intrathecal baclofen (ITB) for severe spasticity was licensed in 1992. Small trials have shown it to be both safe and effective in MS and a more recent study demonstrated its usefulness in people with MS who are walking. However, despite this, it is not as widely used as expected given the number of people with MS and the frequency of spasticity. This appears to be due to a combination of several factors. Firstly an underestimation by neurologists of the impact of spasticity on quality of life; secondly concerns by doctors over the costs and safety of ITB; and thirdly a lack of awareness by patients, carers and health professionals of the potential benefits of treatment.
Does intrathecal baclofen help everyone?
Not everyone responds or is appropriate for ITB. After careful assessment by a multidisciplinary team including a physiotherapist, therapeutic goals are defined and a trial of ITB is planned. Goals may be around walking, transfers, seating or comfort.
The trial is carried out in hospital. Baclofen is injected into the CSF by performing a lumbar puncture. The peak effect of this is seen after four hours and the assessment and measures are repeated by the team. Goals are reviewed and a decision made between the team and the individual as to whether goals are achievable and whether to proceed to pump implantation. If it is not clear whether ITB is appropriate a second trial can be performed at a higher or lower dose.
How is the dose of intrathecal baclofen monitored?
Once the pump is in place it is necessary to adjust (titrate) the dose for the individual. The aim is to find the dose that decreases spasticity enough to achieve the goals and allows for the oral drugs to be tailed off, without causing unwanted side effects. This process can take a few weeks.
The dose is changed by telemetry; a handheld programmer is positioned close over the pump site. Doses can be changed by minute amounts as well as being varied throughout the day to fit with the person's lifestyle. For example, in someone who is walking, the dose may be slightly lower in the daytime to help with walking and higher at night to ensure they sleep well with no spasms or discomfort.
The pump needs to be refilled by the specialist team every four to six months; this is a simple procedure that involves placing a needle through the skin of the abdomen and into the pump reservoir. In addition, the battery life of the pump is about seven years so it is necessary to change the pump through another operation every seven years.
How can people find out if intrathecal baclofen is for them?
Anyone with troublesome spasticity or spasms that are not helped by oral medication, or who is experiencing side effects, should consider ITB. In the past people with MS who are walking were often told "you're not bad enough for that" or "it's not possible to walk with ITB, it will take you off your feet". Although both of these may be true, it is important to discuss this and have a detailed assessment with a neurophysiotherapist and neurologist or rehabilitation physician to look at whether spasticity is being best managed and whether it is helping or hindering mobility.
Often with people who are walking it is impossible to say for sure whether ITB could help until the trial is performed. Around the UK there are many neurological or rehabilitation centres who offer a spasticity service; asking to be referred is the first step to assessment for ITB.
My baclofen pump
In 2006, I developed a gastric ulcer which the gastrologist said was a result of the baclofen I was taking to manage the stiffness and spasticity in my legs. I came off the drug but within six months I started to experience pain and spasm in my right leg. I was given an alternative drug, tizanidine, but with very limited results.
The pain in my right leg was stopping me sleeping properly and the muscle stiffness made it extremely difficult to get into the car or drive, even with an automatic car converted to hand controls. I started using a walker and eventually a wheelchair. Unable to walk, I retired from work. Life was very difficult.
I started to research any treatment I could find. I tried the hyperbaric oxygen chamber in my local MS Therapy Centre, which helped my bladder symptoms but not my spasms. I also had physiotherapy, but the spasms were so bad that the local NHS physio was unable to help.
Then I came across intrathecal baclofen therapy in information from the MS Trust. I was seen by the team at the National Hospital in London, who gave me the trial dose. The result was excellent, so I had the operation to insert the pump in 2009.
I stayed in hospital for three or four weeks to have intensive physiotherapy to improve my mobility and then returned weekly for follow up physiotherapy until I was able to gain more strength in my legs. If it is possible, I would recommend that anyone having the pump inserted remain in hospital for physio.
I'm happy to report that the procedure is 100% successful. I'm generally not aware of the pump which sits quite deep and does not feel heavy. I don't wear tight fitting clothes. If I did, I guess you might see the bump. I still use a T-Roll in bed and therefore sleep on my back rather than on my right side where the pump is. I carry a card when going through scanning machines at airports, though as yet I have never set off the alarm. I love gardening and when kneeling I can only get down so far on that side as the pump is in the way. That is the only time I am aware of it. Due to position of pump, I need to have a high fibre diet.
Every six months I return to have pump refilled by the spasticity nurse. This is a very simple, pain free procedure. The nurse and the doctor discuss how things are going and set the new dose. The team are always available to answer any questions no matter how small. The battery life is about six years and it will be necessary to have another operation to replace the battery.
These are small inconveniences that are worth putting up for the better quality of life.
- Multiple Sclerosis 2004;10:589-595. Summary Prevalence and treatment of spasticity reported by multiple sclerosis patients.
- European Journal of Neurology 2011;18(9):1122-1131 Summary A randomized, double blind, placebo-controlled, parallel-group, enriched-design study of Nabiximols (Sativex) as add-on therapy, in subjects with refractory spasticity caused by multiple sclerosis.
- Journal of Neurology 2006;253:563-569. Summary Long-term intrathecal baclofen therapy in ambulatory patients with spasticity.
- Multiple Sclerosis 2011;17(5):623-629. Summary Intrathecal baclofen in multiple sclerosis: Too little, too late?
- London, Informa Healthcare, 2006, 85-105. In Stevenson VL, Jarrett L. eds.Spasticity management: a practical multidisciplinary guide.