Neurological Aspects of Arachnoiditis

IMPORTANT NOTE:

The information in this article is for general purposes only and is NOT a substitute for medical consultation. You should NEVER attempt to self-diagnose.

 

Part Two:

MUSCLE TWITCHING, CRAMPS AND JERKS: ABNORMAL MOVEMENT

In the 1999 survey, 81% of respondents experienced problems with muscle twitches/cramps/jerks.

These neuromuscular disorders are very common and troublesome problems for many arachnoiditis patients.

Stiffness affected 79% of respondents in the survey. This non-specific term may however, include joint stiffness as well as muscle stiffness.

There is a considerable range of muscular problems, from small, painless, transient twitches right through to extremely painful spasms, and sustained muscle stiffness.

Fasciculations: muscle twitches

Fibrillations spontaneous contraction of a single muscle fibre, not usually visible.

Myokymia: irregular firing of multiple muscle fibres spontaneously, in bursts

Spasms: arachnoiditis patients tend to refer often to ‘muscle spasms’, which in fact may well actually be cramps or myoclonic jerks

Myoclonus: a brief, sudden, shock-like muscle contraction, mediated by an electrical nerve discharge originating in the central nervous system

Drug-induced myoclonus: about 80 causal agents (toxins and drugs) including:

• Tricyclic antidepressants e.g. amitriptyline
• SSRIs e.g. Prozac
• Penicillin
• Morphine
• Hydromorphone (an opiate related to morphine)
• Phenytoin
• Midazolam
• Pseudoephedrine (available in some over-the-counter common cold preparations)

Treatment: Clonazepam(benzodiazepine), valproate (anticonvulsant); some reports of baclofen, fluoxetine (an SSRI antidepressant), propanolol (antihypertensive) and 5-hydroxytryptophan (5-HT) being of help.

There is no treatment for negative myoclonus (asterixis, postural lapses)

Cramps: Sudden involuntary painful muscle contractions:

Treatment: Acute cramp may be relieved by stretching the relevant muscle.

Preventive measures include: avoidance of excessive sugar intake and caffeine. A diet with plenty of potassium rich foods such as bananas is helpful.

Regular stretching of calf muscles during the day, using a footboard at night, or dangling the feet over the edge of the bed if lying prone.

Quinine 300mg(especially for nocturnal cramps);phenytoin or carbamazepine (anti-convulsants). Note quinine interacts with other medication such as: cimetidine, digoxin, anticoagulants, antacids.  You can also obtain quinine in Tonic Water.

Vitamin E 400-800 IU per day has also been reported as being helpful. Calcium supplements (0.5-1g four times a day) may be useful, as may riboflavin 100mg 4 times a day (vitamin B2): note that some common medication used in arachnoiditis patients: e.g. tricyclic antidepressants (amitryptiline being the most frequently used) can contribute to riboflavin deficiency. Magnesium 400mg daily may also be used.

The anticonvulsants carbamazepine 200mg twice or 3 times a day, gabapentin 400mg three times a day or phenytoin 300mg 4 times a day ; methocarbamol (Robaxin), verapamil 120mg 4 times a day, tocainide 200-400mg twice a day, and diphenhydramine (Benadryl) 50mg 4 times a day have also been reported as helpful but there are no specific scientific studies of their use. It is essential to normalise any metabolic abnormalities.

Spasticity

Stiffness of the muscles, often with generalised increased muscle tone, is a common problem in arachnoiditis patients. The term encompasses:

•  involuntary muscle contractions
• stiffness of the muscles; may alternate with floppiness
• hyperactive reflexes (may include clonus: a reflex which is a spasmodic alternation of muscle contraction and relaxation, usually in the calf muscle, the foot being sharply bent upwards towards the thigh and being held in mid position. Persistent clonus can interfere with putting shoes on)

Treatment:

1. regular Range of motion (ROM) exercises : these can reduce the reflex activity
2. application of heat/ice in some patients
3. physiotherapy to improve function in some muscle groups: e.g. trunk control, elbow extension
4. orthotic devices: e.g wrist splint: placing a joint in a position that allows maximum function
5. Drug therapy: Baclofen, diazepam and dantrolene sodium are the most commonly used medications. Tizanidine (Zanaflex) is a relatively novel drug being used. 

Baclofen: 5mg 3 times a day (can be increased every few days to maximum of 80mg total daily dose). Side effects: lethargy, weakness, nausea, pins and needles; note: must not be discontinued suddenly as this could precipitate seizures.

Diazepam and clonazepam: benzodiazepine drugs; primarily used in patients with spasticity of spinal origin. Side effects include sedation, muddled thinking and dependence (hence withdrawal on stopping: not the same thing as ‘addiction’ in the generally accepted sense of the term).

Dantrolene: more often used in spasticity of cerebral (brain) origin.

Tizanidine: thought to cause less weakness; has been used in patients with MS. Dose starts as 4mg at 6-8 hour intervals (max. daily dose should not exceed 36mg). The UK Tizanidine Study Group found that whilst tizanidine improved spasticity without compromising muscle strength, there was no apparent improvement in functional measures or activities necessary in ADLs. Night-time insomnia may be more significant in Tizanidine than Baclofen.

Other drugs: clonidine: a drug developed to treat high blood pressure; rarely used specifically to counter spasticity; available as a skin patch.

Gabapentin: may be prescribed to relieve neuropathic pain: has also been found to be effective in treating spasticity in MS.

Botulinum toxin: injections of the toxin responsible for botulism (Clostridium botulinum) into the relevant muscles has been found to relieve localised muscle spasm (e.g. blepharospasm); it achieves this by damaging the nerve fibres which transmit the signals to the muscles to contract. Localised paralysis of the muscles begins within 24-72 hours, being maximal at 5-14 days. However, the effects are temporary, lasting 12-16 weeks.

 It has been helpful in patients with severe spasticity after stroke or with severe MS.

Intrathecal baclofen: administered via the ‘pump’: is being used in children with cerebral palsy.

Therapeutic nerve blocks: use of phenol (3-6% solution) and alcohol (50%) solution may effect a block for weeks to months; however, there is a risk of abnormal nerve regrowth. 

Note: invasive treatments are not recommended by the Arachnoiditis Trust but are included here for completeness.

Restless legs syndrome

RLS is an unpleasant sensation in the legs (and occasionally the arms) that occurs at rest and is relieved by movement.

RLS may be primary or secondary to diseases or drugs.

Systemic diseases associated with RLS include:

• diabetes
• rheumatoid arthritis
• spinal cord and cauda equina damage
• radiculopathies (nerve root damage: as in arachnoiditis)
• thoracic spinal lesions
• complete spinal cord injury
• neuropathy
• vascular disease including congestive heart failure
• Parkinson’s disease
• End-stage renal disease
• Iron deficiency
• Folate deficiency

Drugs include:

• Paroxetine
• Mianserin
• Phenytoin
• Caffeine
• Alcohol
• Nicotine

Treatment:

1. treat underlying causes: e.g. iron deficiency, folate deficiency
2. general measures: limit smoking, alcohol, caffeine; discontinue aggravating medication if possible
3. drug treatment:

Clonazepam (benzodiazepine); Carbamazepine (Tegretol)or Gabapentin (anti-convulsants); Sinemet, Pergolide, Pramipexole (anti-Parkinsonian); Clonidine

Muscle pain

Inflammatory myopathies (disorders of muscles) and other ‘collagen-vascular diseases’ can feature muscle pain and tenderness. Bearing in mind the possible link between arachnoiditis and autoimmune conditions, disorders such as polymyalgia rheumatica need to be considered.

However, in the majority of cases, muscle pain will arise secondary to the abnormal spinal dynamics seen in most arachnoiditis patients who have had (or continue to have ongoing) spinal problems. Often a diagnosis of fibromyalgia or myofascial pain syndrome is put forward by way of explanation; if so, it must be remembered that these features are likely to be secondary to the underlying arachnoiditis, rather than a separate disease entity. Corticosteroid withdrawal can cause muscle (and joint) pain.

Neuromuscular disorders and endocrine disease:

Note that there appears to be some association between thyroid disease of various types and previous myelogram: this is a feasible situation because myelogram dyes contain iodine.

Hypothyroidism (underactive thyroid) : can cause:

• muscle pain, cramps, stiffness; pins and needles, weakness.

Hyperthyroidism (overactive thyroid)

• Fasciculations and cramps

Hypoparathyroidism:

• Spasms: foot and wrist (tetany)
• Carpal tunnel syndrome
• Cramps, fasciculations, weakness
• Ataxia

Hyperparathyroidism:

• Fasciculations

Adrenal insufficiency:

• Muscle fatigue, mild weakness, cramps and muscle pain

Myopathy: "disease of muscle" that causes problems with the tone and contraction of skeletal muscles (muscles that control voluntary movements.) ranging from stiffness (myotonia) to weakness, with different degrees of severity.

Toxic myopathies: causative agents include alcohol, Organophosphates, Colchicine, D-penicillamine etc.

Focal muscle damage can be caused by Pethidine, Pentazocine, Heroin, antibiotics in infants, Penicillin and Diphenhydramine.

Prolonged corticosteroid treatment is associated with a chronic proximal myopathy. (limb girdles especially).

NEURALGIA:

Neuralgia is the term used to describe pain arising from a nerve. Examples include:

• Trigeminal neuralgia (TGN): pain in the face: from the mouth round to the ear; right sided in 60% of patients, both sides in only 3%. Women are affected more than men. Attacks (clusters) may last for days or months; triggers include: touch, cold wind, speaking or eating. After an attack, there may be a period in which the area is hypersensitive to touch etc. and this may in turn be followed by a dull ache. Intervals between attacks range from weeks to years. TGN may be associated with difficulty in eating (thus weight loss) and depression. Atypical TGN (also termed trigeminal neuropathy)is described as a deep burning pain in the face. The pain is constant, with a deep aching quality; trigger zones on the skin of the face or inside the mouth can often be detected.
• Geniculate neuralgia: pain deep in the ear(“an ice pick in the ear”), triggered by chewing, swallowing or talking. Always only on one side. May be accompanied by increased salivation, bitter taste, tinnitus and vertigo. (rare)
• Glossopharyngeal neuralgia: pain in the ear, base of tongue, or beneath the angle of the jaw; may be triggered by swallowing, talking, coughing. (rare)
• Superior laryngeal neuralgia : pain in throat, under the jaw or ear; triggered by swallowing, straining the voice or head turning. (rare)
• Occipital neuralgia: describes a cycle of pain starting at the back of the head and moving to various other areas on the head, including the temples and the face.
• Pudendal neuralgia: this affects the area around the anus, the rectum and the vulva /vagina or penis/testicles. Acute testicular pain requires medical assessment to exclude hernia, orchitis or testicular torsion. Chronic testicular pain may be due to chronic epididymitis (usually there is a history of bouts of acute epididymitis, or scrotal/groin surgery) :pain may be on one or both sides. This condition is chronic inflammation of the epididymis, which is part of the testicle. In women, vulvodynia, pain in the vulva, and dyspareunia (pain in the vagina on intercourse)may be due to a variety of problems including infection. Rectal pain in both sexes should be checked out to exclude local pathology such as anal fissure.

Treatment of neuralgia:

Looking at the typical treatment of TGN:

The usual therapy is with an anticonvulsant such as carbamazepine or gabapentin.  Occasionally, sodium valproate may be used.

PERIPHERAL NEUROPATHY

Peripheral neuropathy is a common condition which involves damage to the peripheral nerves, i.e. nerves once they have left the spinal cord. It is often called the ‘Silent Disease’ because many people are unaware of its existence. A recent book suggests that around 25 million Americans may have this condition!

Peripheral neuropathy (PN) can also be subdivided into the type of nerve function which is affected:

1)       Sensory (sensation loss)

2)       Motor (weakness)

3)       Sensorimotor (combined)

4)     Autonomic: (involuntary nervous system which regulates body functions such as blood pressure, sweating etc.)

Sometimes no causative factor is found: the condition is then termed ‘idiopathic neuropathy’.

Note that mononeuropathy can be caused by direct pressure in activities such as gardening, stooping, jobs with repetitive mechanical duties (especially if using power tools such as routers, jack hammers etc.) A rather amusing one is ‘back pocket sciatica’ which arises from sitting on a wallet!

*Diabetes is probably the commonest cause of peripheral neuropathy; the majority of patients with insulin dependent Diabetes will develop a degree of the condition, although it may remain subclinical (no symptoms).

The experience of peripheral neuropathy:

• Inability to bear weight on legs
• Inability to sense temperatures>> accidents with burns and scalds
• Severe burning pain in numb areas: worse at night
• Feeling as if walking on broken glass
• Feeling as if hands/feet are thawing out after being frozen
• Inability to tolerate bed sheets, contact with partner’s body in bed
• Loss of balance and co-ordination
• Disrupted sleep pattern
• Depression
• Dizziness

Symptomatic treatment: the mainstay of PN therapy:

A.      For burning pains: antidepressants such as amitriptyline; anticonvulsants such as gabapentin; mexiletine; Ultram (tramadol)

B.       For shooting/stabbing pains: anticonvulsants: Phenytoin/tegretol/gabapentin/clonazepam

C.       For persistent aching pain: clonidine; gabapentin (baclofen is associated with muscle spasm/cramps)

Pyridoxine (Vitamin B6) has been found to be a useful measure of nutritional support following peripheral nerve damage; doses of up to 250mg/day have been used. Alternatively a good vitamin B complex preparation might be helpful.

Anti-oxidants such as gamma-linoleic acid (GLA) found in Evening Primrose Oil, and alpha-lipoic acid have recently been found to be of some help in reducing the symptoms of PN.

General measures:

Use of hot/cold:

Heat tends to relieve sore muscles whereas cold alleviates pain by numbing the area. However, arachniacs vary as to whether they can tolerate heat or cold; extremes of either can potentially be damaging if you have decreased temperature sensation, so don’t use either heat/cold for more than 20 minutes maximum.

COMPRESSION NEUROPATHIES:  carpal tunnel syndrome (CTS) cubital tunnel syndrome , thoracic outlet syndrome (TOS) and tarsal tunnel syndrome all share similarities with arachnoiditis-related neuropathy.