Ana sayfa | MS’in Derinliği  | MS Slide Resource

Spasticity is an involuntary increase in muscle tone, which results from structural lesions of the cerebrum, brainstem, or spinal cord. Although it is one of the most frequent and disabling symptoms of MS, it is difficult to define comprehensively because of inadequate understanding of the neurobiology of the motor system. From a clinical point of view, spasticity consists of three elements:

• increased muscular tone causing resistance to passive movements

• impaired active movements

• uncontrolled flexor responses and spasms (hyper-reetkinligini to external stimuli, e.g. increased and diffusing tendon reflexes, extensor plantar reactions, clonus and paresis).⁴¹

When defined using these terms, as many as 90% of clinically-definite MS patients suffer from some degree of spasticity.⁴¹

Clinical features

In MS, spasticity is usually most severe in the legs and trunk and is often accompanied by weakness. This often causes difficulties with ambulation and results in a stiff-legged, spastic gait. Spasticity of the spinal musculature can lead to abnormal posture, sciatica and lower back pain. In addition, spasticity may be accompanied by pain, cramping and contractures causing sleep disturbances. The latter can result in severe muscle imbalance and joint subluxation or dislocation. Spasticity may restrict the patient's normal activities and make nursing care difficult.^11,13,14

Increased extensor tone may lead to extensor spasms. These are seldom painful or disabling, but they often occur at night and disturb sleep. In contrast, flexor spasms are frequently painful. They can make sitting in a wheelchair impossible. Bedsores or urinary infections are prone to occur, and these further increase flexor and adductor spasm.¹¹

Treatment

It must be recognized that some spasticity may be advantageous in weak patients, enabling them to sit, stand and walk. Therefore, it is important to be sure that alleviation of spasticity will have a beneficial effect and will not increase disability.⁴²

Oral medication

Oral medication is the initial treatment for mild to moderate spasticity. Baclofen is one of the most widely-used drugs. It reduces the frequency and severity of flexor and extensor spasms and reduces abnormally high muscle tone.⁴¹ Baclofen activates GABA_B receptors in the CNS, and inhibits spinal cord reflexes.^43,44

The antispastic effect of benzodiazepines (e.g. diazepam) is similar to that of baclofen, but these drugs cause more pronounced side effects, such as sedation and dependency. They exert their effect by activating GABA_A receptors at various sites throughout the CNS.⁴³

Dantrolene is a peripherally-acting skeletal muscle relaxant which directly impairs the excitation-contraction coupling mechanism in muscle.⁴² It is very effective in relieving severe muscle spasms but, as it also inhibits voluntary muscle power, it can produce muscular weakness. Its use is also limited by hepatotoxicity.⁴³

Clonidine and tizanidine are ₂-adrenergic agonists that inhibit spinal cord reflexes, therefore reducing the severity and frequency of spasms.⁴⁵

Parenteral medication

To treat focal (localized) spasticity, injections of phenol or alcohol have been used to damage nerves and weaken muscles. The effects can last for several months, but the procedure causes pain and is not fully reversible.

Botulinum toxin, injected into the endplate zone of a muscle, reduces or abolishes the release of acetylcholine from presynaptic motor axons thereby paralysing the muscle (chemical denervation). The effects generally last for several months, but the technique is not widely used.³²

Intrathecal baclofen, using an implanted drug pump effectively relieves severe spasticity. Side effects (lethargy and respiratory depression) are rare when the device is implanted in the thoracic region for use on the lower limbs. This technique is especially useful in patients with flexor spasticity who are immobile.⁴⁵

Surgery

Surgery is used in severe cases of spasticity when drugs are ineffective. Techniques include transection of adductor tendons, and radical surgical procedures, such as posterior and anterior rhizotomy (surgical division of a nerve root).⁴¹ Microsurgical techniques (e.g. selective division of peripheral nerves) are now being used in specialized centres.⁴⁵

Rehabilitation

Rehabilitation of patients with spasticity is an important adjunct to pharmacological and surgical treatment. Removal of trigger factors, such as urinary tract infection or pressure sores, which can exacerbate the condition, may decrease the severity of spasms.¹¹ Physical treatment is also important: regular passive stretching of affected muscles can be a very effective antispastic treatment.⁴⁵

Tremor

Intention tremor

Intention tremor is a characteristic feature of MS, caused by lesions in the cerebellum or the cerebellar outflow pathways. It occurs when a patient attempts voluntary movement, i.e. reaching out to touch an object. Intention tremor is known by a variety of other names including action tremor and hyperkinetic tremor. The degree of its effect varies, but in rare cases it can cause total disablement.^11,46,47

Other types of tremor

Postural tremor is also characteristic of MS, although it is much less common than intention tremor. Postural tremor occurs during a sustained posture, such as when the arms are held outstretched. A postural tremor affecting the head and neck is a frequent symptom of MS. It has been postulated that lesions in the cerebellum or the midbrain may be responsible for postural tremor.^11,48,49

Rest tremor occurs during rest or relaxation. It is very rarely seen with MS except in cases where the substantia nigra or nigrostriatal tract is involved (as in Parkinson's disease).^11,49

Treatment

There are three main approaches to the treatment of tremor in MS patients.

Oral medication

Drugs are the first line therapy for the control of tremor, but the results are usually disappointing. Beta-blockers (particularly propranolol) and low dose barbiturates (phenobarbitone and primidone) are classically used to treat postural tremor.⁴⁹ Drug control of intention tremor is rarely effective. Limited successes have been reported for the control of both intention and postural tremor in clinical trials of isoniazid and carbamazepine.^48,50

Orthotic devices

Orthopaedic appliances have some benefits in the control of intention tremor. The attachment of wrist bands containing small weights can reduce tremor by increasing the inertia of the system; however, adding excessive weights can increase tremor.⁴⁷

Tremor severity has also been reduced using a computer-controlled mechanical damping device, which can attenuate the tremor while allowing purposeful movement to take place. Such devices are currently in development and will need to be simplified and miniaturized to be of practical use.⁵¹

Thalamic surgery

Cerebellar tremors can be improved surgically, by creating lesions in the ventrolateral nuclei of the thalamus (stereotactic thalamotomy). The procedure can significantly improve both intention and postural tremor, but it carries a high risk of complications and may even exacerbate the patient's MS. Furthermore, the operation is irreversible and cannot be repeated, so it is used only as a last resort.^49,52

Long-term electrical stimulation, using electrodes implanted into the thalamus, has been shown to produce a similar improvement, with a much lower risk of permanent adverse effects. However, experience with this form of therapy is limited to a small number of MS patients, and the costs are extremely high.^46,49

Bladder dysfunction

Bladder dysfunction occurs in around 75% of patients at some time during the course of their disease, and persists in up to 50% of cases. It is usually caused by spinal cord lesions, and the frequent involvement of the spinal cord in MS explains the high proportion of patients who suffer from bladder problems.⁵³

Bladder symptoms are very troublesome, and a mobile patient may be rendered housebound as a consequence.⁵⁴ Moreover, such symptoms can put relationships under great strain and can contribute to a patient's depression.⁵³

Neurological control of the bladder

Neurological control of the bladder:

• storage

• voiding.

To operate these activities, two neural circuits exist; one which allows the bladder to fill, the other which is activated to cause voiding. These circuits are controlled by the micturition centre located in the pons. Higher centres in the frontal lobes are thought to act on the pontine centre to switch it between storage and voiding. In healthy individuals, the sympathetic system controlling bladder storage is in operation for most of the time.⁵⁵ The detrusor muscle of the bladder is relaxed, and the urethral sphincter is contracted. During micturition the parasympathetic system contracts the detrusor, whereas the sphincters are relaxed.

The peripheral nerves to the bladder arise from the sacral region of the spinal cord, just below the origin of the nerves to the legs. Studies have shown that bladder dysfunction is closely linked to pyramidal symptoms and the severity of paraparesis. This is because any spinal cord damage above the sacral region will affect the nerves to the bladder.⁵⁵

Storage problems

Symptoms such as urgency, frequency and daytime urge incontinence are features of detrusor hyper-reflexia. This is a condition which affects storage of urine in the bladder. Instead of expanding as the volume of urine increases, the bladder wall develops spontaneous waves of contraction which are sensed as an urgent need to micturate.⁵⁴

Voiding problems

Other symptoms, such as hesitancy, interrupted stream, enuresis and incomplete bladder emptying are disorders of voiding.⁵⁵ These are due to poorly sustained detrusor contractions (which obstruct voiding) and/or detrusor-sphincter dyssynergia (incoordination between the detrusor and sphincter muscles). Incomplete bladder emptying may exacerbate hyper-reflexia, and can be easily demonstrated by measuring the volume remaining after micturition.⁵⁴

Management

Bladder symptoms can be effectively alleviated. Treatment is aimed at minimizing the effects of both detrusor hyper-reflexia and incomplete bladder emptying. Treatment should be based on the individual patient's needs, and be both flexible and reversible.^54,55,56

Detrusor hyper-reflexia

Anticholinergics such as oxybutynin, imipramine and probanthine are used to treat detrusor hyper-reflexia. Side effects of these drugs include dry mouth and constipation. As anticholinergics can exacerbate incomplete bladder emptying, residual urine volumes after micturition should be monitored.⁵⁵

In severe cases of urinary incontinence, the infusion of capsaicin into the bladder has been shown to reduce hyper-reflexia in a small number of patients, for up to 5 months. However, this form of treatment is still experimental.⁵⁵

To reduce micturition at night, desmopressin spray can be used. Taken before bedtime, the spray has the effect of reducing urine output for 6 to 8 hours.⁵⁵

Chronic retention

The treatment of choice for chronic retention due to post-micturition residue is clean, intermittent self-catheterization. This technique has revolutionized the management of MS patients with neurogenic bladder dysfunction. The procedure is performed by the patient 3 or 4 times every 24 hours, depending on the patient's bladder storage capacity.^54,55

Some improvement in bladder emptying has been achieved with alpha-blocking agents such as phenoxybenzamine and prazosine, although these can lower blood pressure. Muscle relaxants (baclofen, diazepam, dantrolene) have also been used but can cause muscle weakness and general fatigue.⁵⁴

In MS patients who are too disabled to perform self-catheterization, long-term catheters are an option. Suprapubic catheters, inserted into the bladder through the lower abdominal wall, are generally preferable to long-term urethral catheters.⁵⁵

Complications of bladder dysfunction

Lower urinary tract infections can occur as a result of chronic retention and poor hygiene during self-catheterization. These infections can generally be treated with a short course of antibiotics. Continuous treatment with low-dose antibiotics is not recommended since it does not eliminate infection and may encourage bacterial resistance. Infections of the upper urinary tract are rare in MS.⁵⁵

Bowel dysfunction

The symptoms of bowel dysfunction, for example constipation and faecal incontinence, are common in MS, even in mildly disabled patients. In a study of 280 unselected patients with MS, constipation was present in 43% and faecal incontinence in 51%, with 68% of patients affected in total.⁵⁷ However, faecal incontinence is a social disability and patients are unwilling to admit to it unless asked directly. Consequently, its presence may often go unreported.⁵⁷

The neurological basis for bowel dysfunction is not fully understood. The site of central control of defaecation is probably in the pons. In turn, this centre is probably influenced by both cortical and spinal centres.⁵⁸

Generalized muscle weakness, immobility and use of constipating medications in MS patients, may contribute to constipation.⁵⁷ Faecal incontinence may occur in MS patients as a result of disturbed colonic motility. It may also be caused by loss of voluntary control of the anal sphincter muscle, and abnormal rectal sensation caused by damage to sensory nerves.⁵⁸

Treatment

Bowel-related symptoms in MS have received little attention and the underlying pathophysiology needs to be better understood in order to identify effective therapies.⁵⁷

Treatment of bowel symptoms currently relies on controlling bowel emptying to ensure that it occurs at a time that is socially acceptable to the patient.

Treatment of constipation

Lactulose (a laxative), and/or laxative suppositories first thing in the morning, are used to treat constipation.⁵³

Treatment of faecal incontinence

Loperamide, an antidiarrhoeal drug, can be used to reduce faecal incontinence.⁵³

Sexual dysfunction

Sexual problems often cause MS sufferers much distress. Despite this, there have been few specific studies in this area and the number of publications on the subject is limited. The neurological damage associated with MS could affect sexual function in many different ways.

Lesions in the CNS can disrupt the nerve tracts that convey impulses to the genitalia, resulting in impotence or loss of ejaculation. They can also affect the mechanisms regulating libido and can alter the sensation of orgasm. Paraesthesiae and other sensory symptoms, especially in the genital area, can interfere with the perception of pleasurable sensations and decrease the ability to achieve an erection or vaginal lubrication. In addition, the occurrence of weakness, spasticity, ataxia, fatigue, incontinence, pain and mood disorders can all have a severe impact on sexual etkinligini.^59,60

Sexual dysfunction in men

Most of the published information about sexual problems in male MS patients relates to erectile dysfunction. Recent studies indicate that the prevalence of erectile dysfunction in MS is probably about 60%.⁵⁹ Most studies show that erectile failure in MS is usually associated with neurogenic bladder dysfunction and pyramidal impairment in the lower limbs. Little is known about ejaculatory dysfunction. Data from two questionnaire studies indicate that around 40% of men with MS have difficulty in achieving ejaculation.⁵⁹

Treatment

The most effective treatment for impotence is the use of self-administered intracorporeal injections of papaverine. The usual starting dose is 5 to 10 mg; this can be gradually increased until an optimal dose is reached. The main complication of this therapy is a prolonged erection, and patients must be aware of the need to obtain medical advice if this occurs. In cases where it is not possible to find a dose of papaverine that is effective without causing prolonged erections, prostaglandin E₁ can be used instead.⁵⁹

Surgically-implanted penile prostheses provide an alternative method of treating impotence. These prostheses are either permanently rigid, or can be inflated using a vacuum pump, which draws blood into the penis under reduced air pressure.⁶¹

There are no established techniques to bring about ejaculation during intercourse, although electro-ejaculation techniques are available to obtain semen for male infertility. Some patients report that using vibrators or taking yohimbine is helpful. Yohimbine is an ₂- antagonist, which when taken orally 1 to 2 hours before attempting intercourse has been reported to improve erectile function, enhance sexual sensations and assist in ejaculation. The usual starting dose is 5 mg, which can be increased up to a maximum of 20 mg.⁵⁹

Sexual dysfunction in women

There is little information available about sexual problems in women with MS. The results of two small studies indicate that about 50% of women with relatively mild MS have major sexual problems.^60,62 The most common symptoms are loss or decrease of libido, lack of vaginal lubrication, loss or altered genital sensation and failure to reach orgasm. As with male sexual dysfunction in MS, the occurrence of these symptoms is strongly associated with bladder dysfunction.

Treatment

Lack of vaginal lubrication can be overcome by using lubricating gels, and topical local anaesthetics can help to relieve some sensory disturbances. Failure to reach orgasm is occasionally helped by the use of electrical vibrating devices. However, for most patients, general sexual counselling (about issues such as contraception, coital positions, the use of sexual aids and alternative sexual activities) forms the mainstay of treatment. In addition, it is very important to treat other symptoms of MS that may be having an adverse effect on sexual function (e.g. spasticity and urinary incontinence).^60,61

Psychological symptoms

Psychological problems, such as depression, emotional lability and cognitive dysfunction, are common in MS.⁶³ Recognition of these disorders is important, because they can cause much disability and social stress, but are readily treatable.¹⁴

Depression

Reported prevalence rates of depression in MS vary considerably, but a recent review suggests that the true rate ranges from 27% to 54%.⁶⁴ Typical episodes are moderately severe and are characterized by feelings of anger, worry and irritability. More passive features, such as self-criticism, a desire to withdraw and a lack of interest, are less frequently found. Depression often has a considerable impact on quality of life, social relationships and job performance. Suicide rates among MS sufferers appear to be higher than in the general population.⁶⁵

There is conflicting opinion as to the cause of depression in MS - whether it is neurologically-based and occurs as a direct result of cerebral plaques, or is caused by an emotional reaction to the chronic, unpredictable disease process and physical disability. Evidence exists to support both theories, and it seems most likely that the aetiology is multifactorial.⁶⁴

Treatment

Antidepressant drugs are the treatment of choice, with amitriptyline regarded as the most effective agent. Other tricyclic antidepressants, including desipramine and imipramine, or newer generation antidepressants, such as sertraline and fluoxetine, may be used.²³

Psychotherapy is beneficial in some cases, especially for patients with active disease.⁶⁶ For example, controlled studies of cognitive-behaviour and insight-orientated group therapy show that these techniques can improve depression in MS patients.^67,68

Euphoria

Euphoria is a sustained change in mood consisting of cheerfulness, happiness and optimism, which persists in spite of the patient's awareness of disability. There is no consensus on the prevalence of euphoria in MS, with reported rates ranging from zero to 63%. This wide variation probably reflects the use of the term euphoria to describe any form of emotional disorder. Euphoria would be a neurologically-based emotional state produced by demyelination, and not a psychological process.

Clinical studies show that euphoria is often associated with severe disability, long duration of symptom evolution, chronic progressive MS, cognitive impairment and enlarged ventricles on computerised imaging scan.⁶⁴

Treatment

No treatment is required, as euphoria is generally not distressing for patients or their families. However, patients and their families should be reassured that this emotional state is not uncommon in MS and is part of the disease process.⁶²

Pathological laughing and crying

Pathological laughing and crying describes a condition in which patients may laugh or weep at the slightest provocation, regardless of their underlying mood. This is usually distressing for patients and can be socially disabling. The condition is rare in MS and generally seen after many years of established disease. Although the exact neurological basis of pathological laughing and crying is not fully understood, it is probably caused by disconnection of the diencephalic or brain-stem centres from right hemisphere or frontal control.⁶⁴

Treatment

Low-dose amitriptyline provides dramatic improvement in some cases. Levodopa or bromocriptine should be tried if amitriptyline is ineffective.^14,64

Emotional hyper-expressivity

Emotional hyper-expressivity is more common than pathological laughing and crying and occurs during the early phases of MS. The condition is characterized by sudden and uncontrolled eruption of an emotion, which can be repeated many times in a short period.²³

Treatment

This condition can be treated by helping the patient to describe his/her emotions using psychological techniques and to control these emotions with the aid of relaxation techniques.²³

Cognitive impairments

The prevalence of cognitive dysfunction is approximately 40% to 45% in the general population of patients with MS, and 50% to 65% in patients who attend MS clinics.⁶⁹ Deficits are usually mild and selective, often occurring in the areas of recent memory, sustained attention, conceptual-abstract reasoning, and the speed of information processing.⁶⁹ Other cognitive functions, such as language, calculation, and visual-spatial orientation tend to remain intact. Severe, global forms of cognitive impairment occur in about 10% of MS patients.⁶³

MRI studies indicate that total lesion area is proportional to the amount of cognitive dysfunction. Atrophy of the corpus callosum correlates with sustained attention deficits, while focal lesions result in specific cognitive deficits, depending upon their location.⁷⁰

Cognitive impairments can affect all aspects of work, social function, and activities of family life, and therefore can have a profound effect on quality of life. However, they are not always apparent during ordinary conversation or routine clinical examination, and can be mistaken for emotional instabilitesini or depression. Accurate assessment of a patient's cognitive status therefore requires a battery of extensive neuropsychological tests.⁶³

Treatment

Two broad approaches are used in the rehabilitation of specific cognitive deficits:

• potentially restorative techniques attempt to improve specific cognitive functions (e.g. attention training)

• strategies or external aids to help patients to overcome certain problems (e.g. training in task-specific routines).⁶⁹

In addition, social stimulation prevents patients from becoming isolated and withdrawn, thereby developing attention and memory, and reducing the progression of cognitive deficits. Therefore, family and group activities are also recommended for patients with cognitive impairment.²³

Fatigue

Fatigue is experienced in a wide range of illnesses, but among patients with MS it is considered to be one of the most frequent and distressing symptoms.⁷¹

Definition

Fatigue can be defined as a sense of tiredness or lack of energy, of unknown origin, greater than expected for the daily effort and degree of disability. In addition, it significantly interferes with the desire or ability to perform basic, daily, physical and intellectual functions.⁷¹

Specific characteristics of fatigue in MS

Most MS patients consider their fatigue to be fundamentally different from that of ordinary fatigue. In particular, fatigue in MS tends to have a much more severe impact on activities of daily living than ordinary fatigue. MS sufferers usually associate their fatigue with impairment of physical functions, such as housework, rather than mental activities. It often interferes with family life, work and social activities, and can prevent patients from being able to fulfil their responsibilities.⁷¹ Other aspects of fatigue appear to be specific to MS: it is exacerbated by heat, improved by cool temperatures and makes other symptoms appear worse.⁷²

Although studies have shown that the majority of patients regard fatigue as either their worst, or one of their worst, symptoms, it does not necessarily worsen with increases in disability.^71,73 The relationship between fatigue and depression in MS is unclear but self-report patient questionnaires have shown fatigue severity to be largely independent of depressive symptoms.⁷²

Cause

The cause of fatigue is unknown. Some studies have suggested that fatigue in MS may be related to the consequences of immune activation within the CNS.⁷⁴ The physiological effects of demyelination and the impaired neurological control of muscle activation, may also contribute to the overall feeling of fatigue.^16,75

Measurement techniques

Since fatigue is a subjective experience, self-assessment scales are the most appropriate measure of the condition. Visual analogue scales are easy for the patient to use but fail to assess the impact of fatigue on daily living. The Fatigue Severity Scale is based on the scoring of several characteristics of fatigue. It is a quick and reliable method, producing a comprehensive scale, rather than a single score. Other scales are available to characterize the mental and physical components of fatigue and their effects on quality of life.^72,76

Treatment

The treatment of fatigue requires a combination of non-pharmacological and pharmacological therapies.

Non-pharmacological therapies include:

• behavioural therapies

• emotional support

• exercise programmes.⁷⁶

In addition, heat-sensitive patients should be advised to reduce ambient temperatures and to dress lightly.¹⁴

The recommended drug is amantadine, an anti-viral agent which has dopaminergic properties. This drug offers modest reduction in fatigue in the majority of patients. Pemoline, a weak CNS stimulant, can be given on a short-term basis, but the drug's stimulant effects and potential for abuse prevent its long-term use.¹⁴

Paroxysmal symptoms

Paroxysmal symptoms may be motor, sensory or visual. They have a tendency to recur in a stereotypical manner. Several of the symptoms are highly characteristic of MS (e.g. dysarthria and tonic seizures), and they are usually an early feature of the disease. A careful inquiry for the presence of these symptoms is important because they can cause significant dysfunction or discomfort but usually respond well to therapy.^{14, 77}

Incidence

Reported incidences of paroxysmal symptoms show that around 4% to 17% of MS patients will experience one or more of these symptoms during the course of the disease.⁷⁸

Characteristics and patho- physiology of paroxysmal symptoms

Although a wide range of paroxysmal symptoms have been reported by MS patients, they share several characteristic features. These common features indicate that the different types of paroxysmal attacks may all arise from the same basic neuronal disturbance. Several experiments suggest the hypothesis that paroxysmal symptoms are caused by ephaptic spread (i.e. 'cross talk') between adjacent demyelinated axons.¹⁷

Types of paroxysmal symptoms

Tonic seizures

Tonic seizures, also known as tonic spasms or paroxysmal dystonia, are sudden attacks of abnormal involuntary postures of one or more limbs, often resembling tetanic spasms. They can be associated with facial grimacing and painful sensations that localize to the same area as the motor symptoms. Consciousness is not disturbed during the seizure, and the patient's electroencephalogram (EEG) remains normal.^14,79,80

Dysarthria and ataxia

Paroxysmal dysarthria and ataxia are highly characteristic of MS. A typical episode begins with a sudden onset of slurred speech accompanied by incoordination of voluntary muscles. This is usually localized to the limbs on one side and may cause the patient to stagger or fall. There may be other symptoms, such as diplopia, numbness, weakness and tonic seizures.^11,14

Sensory disturbances

Common paroxysmal sensory disorders are Lhermitte's sign, numbness, paraesthesiae, itching, and painful or burning sensations. Lhermitte's sign consists of a brief, unpleasant, tingling, shock-like sensation that passes down the spine to the legs, when the neck is flexed. All four limbs may be affected, or, rarely, the arms alone.¹¹

(See the next subsection for a description of painful paroxysmal disorders and their management.)

Differential diagnosis

A number of other conditions can cause symptoms that are similar to the paroxysmal symptoms of MS. These include:

• epilepsy

• hysteria

• tetany

• acute drug-induced dystonias

• transient ischaemic attacks

• hypoglycaemia.

These conditions require specific treatment, so it is important they are ruled out before the link to MS is made.⁸¹

Treatment of paroxysmal symptoms

Paroxysmal symptoms usually respond to anticonvulsant therapy. Carbamazepine is the drug of choice; maintenance doses of 100 to 300 mg per day are usually sufficient to control paroxysmal symptoms without causing major side effects. The response is often dramatic, with complete relief on beginning treatment and temporary relapse on attempted withdrawal of the drug. In cases where carbamazepine does not work, other anticonvulsants such as phenytoin or the barbiturates are sometimes effective.^11,81

Pain

Pain is now recognized as being a common symptom of MS. It can occur as a direct result of demyelination or may be a consequence of other symptoms of the disease. It ranges in severity from mild, short-lived paroxysms to severe, chronic neurogenic pain. Management involves a variety of pharmacological and non-pharmacological approaches, but must be individualized for each type of pain, depending on its pathophysiology.

Epidemiology of pain

The reported prevalence of pain in MS varies depending on the definitions and study methodology used. Two recent studies^82,83 indicate that up to two-thirds of MS patients experience significant pain during the course of their disease, and almost one-half have chronic pain. These studies show also that the frequency of chronic pain increases with increasing age and disease duration, but is not related to age at onset.

Causes of pain in MS and their management

Acute/paroxysmal pain syndromes

The most well-documented of the paroxysmal pain syndromes is trigeminal neuralgia, which occurs in about 1% to 2% of MS patients.⁸⁴ The clinical features of trigeminal neuralgia associated with MS are identical to those of idiopathic trigeminal neuralgia, except that it tends to occur at an earlier age and is more often bilateral.⁸⁴ The first-line treatment is carbamazepine, but some patients are unable to tolerate the relatively high dose that is frequently required. Baclofen and the long-acting prostaglandin E₁-agonist, misoprostol, are effective alternatives in some patients. When medical treatment fails, neurostimulation is usually effective. Alternatively, percutaneous trigeminal rhizotomy (surgical division of the nerve root) or instillation of glycerol in the trigeminal nerve often produces good results.^85,86

There are other paroxysmal pain syndromes, which usually affect the limbs. The duration of the pain is very brief and tic-like, or can take the form of a burning pain that lasts for less than a minute. Painful tonic seizure can accompany paroxysms of pain or immediately follow them. Itching has also been reported as a painful paroxysmal disorder. Carbamazepine is generally very effective in these cases.⁸⁶

Subacute pain syndromes

Causes of subacute pain syndromes in MS are optic neuritis, ulnar and peroneal nerve palsies, vertebral compression fractures (often caused by prolonged use of corticosteroids), and haemorrhagic cystitis (a side effect of cyclophosphamide therapy).⁸⁶

Chronic pain syndromes

A common type of chronic pain in MS is dysaesthetic extremity pain. This is a continuous burning pain, which usually affects the feet and lower legs, but may involve the trunk and arms. It is often worse at night, and is aggravated by heat and walking. The pain is usually accompanied by loss of vibration sense, and is probably due to demyelination in the spinothalamic tracts or posterior columns in the spinal cord. This type of pain is very difficult to treat, although tricyclic anti-depressants (usually amitriptyline or imipramine) are sometimes effective. The clinical results of spinal cord electrostimulation have been disappointing. Cognitive-behavioural approaches are valuable in providing coping techniques and distraction from the pain.^82,86

MS patients frequently experience chronic joint pain, back pain, and radicular pain (e.g. sciatic pain - L5, S1). This type of pain is usually a result of abnormalities of posture and gait caused by alterations in muscle strength and tone. The management of joint and back pain involves the use of non-steroidal anti-inflammatory drugs, and physiotherapy to maintain strength and posture. Intervertebral disc herniation may require surgical treatment.^15,82,86

Painful spasms are another cause of chronic pain in MS. These cause severe, cramping pains, which worsen with increasing disability and spasticity. The features and management of spasticity have been described previously.

Headaches and MS

The association between headaches and MS is most often accidental. A study by Rolak and Brown would suggest that a higher proportion of patients with MS (52%) reported having headaches than matched general neurology patients (18%). However, there was nothing distinctive about the headaches, all of which were either migraine or tension headaches, and they were never associated with clinical exacerbations of MS.⁸⁷

Intractable symptoms

Some of the symptoms of MS are very difficult to treat, with medical or surgical therapies providing negligible benefits. Such symptoms include ataxia, sensory disturbances, muscle weakness and respiratory dysfunction. Certain aspects of supportive care may provide some relief, but, in general, there is little that can be done to alleviate these symptoms.

Cerebellar ataxia

Cerebellar ataxia can interfere with all self-care activities, as well as with transfer skills and mobility. In the lower limbs and trunk, cerebellar ataxia affects the gait and balance, and when combined with spasticity of the lower limbs, results in a characteristic spastic-ataxic gait. In these cases, the patient walks unsteadily with stiff legs and the feet placed too far apart.¹¹

Incoordination in the upper limbs can be extremely disabling, particularly when combined with an intention tremor.¹¹ A variety of drugs have been tested, but most have no more than a dampening effect on the incapacitating tremor.²²

Sensory disturbances

The scattered lesions of MS can cause a wide variety of sensory symptoms and signs. There may be paraesthesiae often described as tingling, and a variety of other odd sensations, such as feelings of swelling, coldness or wetness. These symptoms can be extremely irritating, although they usually do not have a severe effect on daily activities.¹¹

In contrast, painful sensory disturbances can have a profound effect on quality of life. However, these sensations are sometimes relieved by carbamazepine or benzodiazepines, such as clonazepam.

Muscle weakness

Muscle weakness eventually occurs in almost all MS patients. Progressive strengthening exercises have not been proven to be effective in MS, although submaximal exercise, with avoidance of fatigue, may help to maintain general condition and prevent disuse atrophy. Swimming is a beneficial form of exercise, but the water temperature should not exceed 29°C because neurological deficits are commonly exacerbated by heat.⁸⁸

Respiratory dysfunction

Pulmonary dysfunction in MS is caused by disrupted respiratory pattern and weakness of the respiratory muscles. Acute respiratory weakness due to paralysis of respiratory muscles is a possible but rare cause of death in MS patients. The warning signs are rapid shallow breathing and obvious restriction of respiratory movement. Chronic respiratory weakness is common in patients who have lost the ability to ambulate independently because of chronic spinal lesions. Regular physiotherapy may help to prevent secondary complications, but the condition is usually progressive.^11,63

In the past, research into the cause of MS and attempts to find a cure, largely eclipsed interest in symptomatic treatment. There is now a keener realization amongst doctors that, at least for the present, focusing entirely on attempts to halt disease progression is inappropriate. Consequently, recognition and management of symptoms has improved. This has lead to a better quality of life for many patients. Appropriate symptom management can ensure a more active and comfortable existence, despite significant disease.^2,10,13

The increasing recognition of symptomatic treatment benefits doctors too. Dealing with patients suffering from a chronic, sometimes disabling disease, for which there is no cure, can be frustrating. Most doctors want to do something constructive. Tackling MS with symptomatic management alleviates their sense of helplessness.¹²

Most problems can be managed with some success. Doctors must recognize the psychological and social problems that are likely to occur, and understand how to alleviate specific symptoms. Management involves rehabilitation medicine, pharmacological therapy, and surgical techniques, often used in combination.^1,12,15

Bu sayfadaki bilginin en son güncellendiği/doğrulandığı tarih:

11/09/2001

Ana sayfa | Bağlantılar | Kayıt ve geri bildirim | Sözlükçe | Arama motoru ve site haritası | Yerel Bilgiler | Yardım| Bir arkadaşa söyleyin | Sorumluluk almama | Basın Bilgileri | Schering