Syringomyelia and complex regional pain syndrome as complications of multiple sclerosis.

OBJECTIVE: To describe a patient from Southeast Asia with the optic-spinal phenotype of multiple sclerosis who developed syringomyelia and resultant complex regional pain syndrome (formerly named reflex sympathetic dystrophy). DESIGN: Case report. SETTING: Department of neurology at a tertiary care hospital in the Republic of Singapore. PATIENT: A 53-year-old Chinese woman with a history of optic neuritis developed an episode of left hemiparesis leading to a diagnosis of multiple sclerosis. Serial neuroimaging studies revealed an active demyelinating plaque in the cervical area that later progressed into a syrinx. Over a period of 1 year she also developed signs of sympathetic dysfunction including Horner syndrome of the left eye and complex regional pain syndrome in the left hand. CONCLUSIONS: A case of the optic-spinal phenotype of multiple sclerosis that is commonly observed in Southeast Asia is described. This characteristically tissue-destructive form of multiple sclerosis resulted in syringomyelia complicated by a complex regional pain syndrome. Possible pathogenic mechanisms for these associations are discussed.     

Reflex sympathetic dystrophy in children.

Reflex sympathetic dystrophy is a syndrome characterized by pain in one or more extremities, usually associated with vasomotor changes. Its occurrence in childhood has long been thought to be rare. We describe six cases of pediatric reflex sympathetic dystrophy and suggest that this syndrome could be underdiagnosed in children and adolescents. Psychologic problems frequently play a role in this disorder, which often can be treated conservatively. We also point out that the diagnosis is mainly clinical. An early diagnosis can avoid unnecessary tests and potentially can improve response to treatment, and prognosis.     

Use of gabapentin in the treatment of childhood reflex sympathetic dystrophy

Reflex sympathetic dystrophy, a painful syndrome involving an extremity after trauma or injury, is increasingly reported in the pediatric population. Although no clear pathophysiologic mechanism for this disorder has been identified, the role of central serotonin activity seems important. Gabapentin, a new antiepileptic medication, has been demonstrated to be effective in adults with reflex sympathetic dystrophy. The first reported case of a child with a diagnosis of reflex sympathetic dystrophy who was treated successfully with gabapentin is presented.     

Tremor in reflex sympathetic dystrophy.

Postural hand tremor was quantitatively investigated on both sides in 21 patients suffering from unilateral reflex sympathetic dystrophy of the upper extremity. On the affected side, enhanced tremor amplitude, with a mean tremor frequency of 7.2 Hz, was found in 57% of the patients. The appearance of tremor did not correlate to the occurrence of a single clinical symptom of reflex sympathetic dystrophy. On loading with increasing weight, the frequency of this pathological tremor shifted toward lower values, as it is found in physiological tremor. However, the peak frequencies of the electromyogram remained more or less stable. On recovery from this condition, the reflex sympathetic dystrophy tremor disappeared. Acute sympatholytic intervention could normalize reflex sympathetic dystrophy tremor. This would suggest that the sympathetic supply of the affected extremity contributes to the tremor in reflex sympathetic dystrophy. In conclusion, it is suggested that reflex sympathetic dystrophy should be included among the causes of tremor. According to our findings, tremor in reflex sympathetic dystrophy should be regarded as an enhanced physiological tremor.     

Motor paresis improved by sympathetic block. A motor form of reflex sympathetic dystrophy?

Four patients had a characteristic motor paresis that was dramatically improved by sympathetic block. The cause of this paresis could not be determined by the usual neurological examinations. It was similar to reflex sympathetic dystrophy in that the patients experienced severe pain, swelling, coldness, and muscle atrophy in the affected limbs or other parts of the body in the course of their illness. However, the motor paresis could precede the pain or develop after the pain had disappeared. Even in the absence of pain, the motor paresis was exacerbated by sympathetic stimulation using epinephrine, norepinephrine (nor-adrenalin), or isoproterenol hydrochloride (Proternol) loading and was improved by regional intravenous infusion of reserpine or by sympathetic ganglion block. Loading with pilocarpine, atropine sulfate (Bosmin), and edrophonium chloride (Antirex) did not influence the paresis. This motor paresis is thought to be due to abnormally increased sympathetic tone and may be considered a motor form of reflex sympathetic dystrophy. However, motor paresis closely related to sympathetic dysfunction is quite a new condition that we call "sympathetic motor paresis." This is important clinically because a long-standing effect can be expected from permanent sympathetic ganglion block with dehydrated ethanol.     

Sympathetic innervation and function in reflex sympathetic dystrophy

Patients with reflex sympathetic dystrophy have posttraumatic pain disproportionate to the injury and spreading beyond the distribution of any single peripheral nerve. We examined sympathetic neurocirculatory function and the role of sympathetic postganglionic nerve traffic in maintaining the pain in 30 patients with reflex sympathetic dystrophy. Most had had the condition for more than 1 year, and 14 had undergone sympathectomy for the pain. Positron emission tomographic scanning after administration of 13N-ammonia was used to assess local perfusion, and 6-[18F]fluorodopamine was used to assess sympathetic innervation. Rates of entry of norepinephrine in the regional venous drainage (spillovers) and regional plasma levels of L-dihydroxyphenylalanine (the immediate product of the rate-limiting enzymatic step in norepinephrine biosynthesis) and dihydroxyphenylglycol (the main neuronal metabolite of norepinephrine) were measured with and without intravenous trimethaphan for ganglion blockade. 13N-Ammonia-derived radioactivity was less on the affected side than on the unaffected side, whereas 6-[18F]fluorodopamine-derived radioactivity was symmetrical. Thus, perfusion-adjusted 6-[18F]fluorodopamine-derived radioactivity was higher on the affected side. Norepinephrine spillover and arteriovenous increments in plasma levels of L-dihydroxyphenylalanine and dihydroxyphenylglycol did not differ significantly between affected and unaffected limbs, although 4 patients had noticeably less norepinephrine spillover and smaller arteriovenous increments in plasma dihydroxyphenylglycol on the affected side. Trimethaphan decreased the pain in only 2 of 12 nonsympathectomized patients. The results indicate that patients with chronic unilateral reflex sympathetic dystrophy have decreased perfusion of the affected limb, symmetrical sympathetic innervation and norepinephrine synthesis, variably decreased release and turnover of norepinephrine in the affected limb, and failure of ganglion blockade to improve the pain in most cases. These findings suggest augmented vasoconstriction, intact sympathetic terminal innervation, possibly impaired sympathetic neurotransmission, and pain usually independent of sympathetic neurocirculatory outflows.     

Hypnotherapy for reflex sympathetic dystrophy.

Reflex sympathetic dystrophy (RSD) is an unusual, debilitating, chronic pain syndrome thought to be the result of a continuous excessive discharge of regional sympathetic nerves. Supportive and stress-reduction psychotherapies are commonly recommended as adjunctive treatments. Biofeedback is a more direct symptomatic treatment. Although hypnotherapy is effective in altering sympathetic reflex and pain responses, there are no reports of its use for the treatment of RSD. This article reviews some promising results of hypnotherapy with three RSD sufferers. I discuss the role of hypnotherapy as a supportive adjunct to medical treatment. I also explore the possible role of hypnotherapy as a complementary treatment.     

Severe chronic pain with allodynia in Parkinson's disease: a case report]

We report a 61-year-old man with Parkinson's disease, who had a 3-year history of severe chronic pain with allodynia in the lower extremities prior to motor symptoms. He always had tingling pain around the ankles, and tactile sensation induced severe burning pain expanding to the toes and thighs, so his pain was considered to be allodynia. Pain and motor symptoms were ameliorated by L-dopa therapy and exacerbated by withdrawal of L-dopa. Pain is known to occur in Parkinson's disease, but severe pain rarely occurs. To our knowledge, allodynia, which is usually recognized in causalgia or reflex sympathetic dystrophy, has never been reported in Parkinson's disease. Patients with Parkinson's disease may complain severe causalgia-like pain as an initial symptom.     

Reflex sympathetic dystrophy of the face. Report of two cases and a review of the literature

Reflex sympathetic dystrophy of the face is an infrequently reported cause of chronic facial pain. We report the cases of two patients who were diagnosed and treated by sympathetic blockade of the stellate ganglion. Pathophysiologic mechanisms and rationale for treatment are discussed.     

Reflex sympathetic dystrophy: a sympathetically mediated pain syndrome or not?

Because of the controversy concerning the manner in which the sympathetic nervous system is involved in reflex sympathetic dystrophy (RSD), its name was changed to one having no mechanistic connotations. This article reviews the relevant literature in support of not only the taxonomical changes to complex regional pain syndrome (CRPS) but also provides evidence of sympathetic dysfunction demonstrated in animal models of neuropathic pain.     

Abnormalities of cutaneous blood flow regulation in patients with reflex sympathetic dystrophy as measured by laser Doppler fluxmetry

The response of cutaneous blood flow to autonomic stimuli was evaluated in eight patients with clinically staged reflex sympathetic dystrophy and eight healthy control subjects. Blood flow was measured in the affected and contralateral extremities by laser Doppler fluxmetry. Five autonomic stimuli were applied to the contralateral extremity during blood flow measurement in the ipsilateral affected extremity. Affected limbs of patients with reflex sympathetic dystrophy were found to have statistically significantly increased blood flow during the Valsalva maneuver and cold pressor test, while blood flow decreased in normal controls. No significant differences were found in limb temperature or baseline blood flow between patients and controls. Reflex sympathetic dystrophy stage did not affect response to the procedures. Control subjects demonstrated a rhythmic cycling of cutaneous blood flow that was absent in patients with reflex sympathetic dystrophy. These results support a central abnormality of the sympathetic nervous system in reflex sympathetic dystrophy.     

Reflex sympathetic dystrophy. A review

Reflex sympathetic dystrophy is a syndrome of burning pain, hyperesthesia, swelling, hyperhidrosis, and trophic changes in the skin and bone of the affected extremity. It is precipitated by a wide variety of factors in addition to nerve injury. It occurs outside of dermatomal distributions and can spread to involve other extremities without new injury. The diagnosis is primarily clinical, but roentgenography, scintigraphy, and sympathetic blockade can help to confirm the diagnosis. The most successful therapies are directed toward blocking the sympathetic innervation to the affected extremity, in conjunction with physical therapy. The theories proposed to explain the pathophysiology of reflex sympathetic dystrophy include "reverberating circuits" in the spinal cord that are triggered by intense pain, ephaptic transmission between sympathetic efferents and sensory afferents, and the presence of ectopic pacemakers in an injured nerve.     

The effect of spinal cord stimulation in patients with chronic reflex sympathetic dystrophy: two years' follow-up of the randomized controlled trial

Chronic reflex sympathetic dystrophy is a painful, disabling disorder for which no treatment with proven effect is available. We performed a randomized trial in a 2 to 1 ratio of patients, in which 36 patients were treated with spinal cord stimulation and physical therapy (SCS+PT), and 18 patients received solely PT. Twenty-four SCS+PT patients were given a permanent spinal cord stimulation system after successful test stimulation; the remaining 12 patients received no permanent system. We assessed pain intensity, global perceived effect, functional status, and health-related quality of life. Patients were examined before randomization, before implantation, and also at 1, 3, 6, 12, and 24 months thereafter. At 2 years, three patients were excluded from the analysis. The intention-to-treat analysis showed improvements in the SCS+PT group concerning pain intensity (-2.1 vs 0.0 cm; p < 0.001) and global perceived effect (43% vs 6% "much improved"; p = 0.001). There was no clinically important improvement of functional status. Health-related quality of life improved only in the group receiving spinal cord stimulation. After careful selection and successful test stimulation, spinal cord stimulation results in a long-term pain reduction and health-related quality of life improvement in chronic reflex sympathetic dystrophy.     

Bone scanning and diagnosis of reflex sympathetic dystrophy secondary to herniated lumbar disks.

In two cases, reflex sympathetic dystrophy (RSD) was due to herniated intervertebral disk at L4-5. In both cases, bone scanning with technetium 99m pyrophosphate was of value and its use is recommended in diagnosing mild or early cases of RSD. RSD may be the cause of persisting pain after disk surgery.     

Reflex sympathetic dystrophy in a child

We describe a 9 1/2 year old girl who suffered from severe recurrent pain and functional limitation in her right leg with hyperesthesia, hyperalgesia, color change and edema as the presenting symptoms, during the previous two months. All laboratory tests were found to be normal and diagnosis of reflex sympathetic dystrophy was made.

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Sommario Viene descritto il caso di una bambina di nove anni e mezzo che ha sofferto di dolori intensi e ricorrenti e di limitazione funzionale a carico del suo arto inferiore destro con iperestesia, iperalgesia, variazione di colorito dell'arto ed edema. Tutti i tests di laboratorio risultarono normali e fu posta diagnosi di distrofia simpatica.

     

Normal sympathetic nerve activity in a reflex sympathetic dystrophy with marked skin vasoconstriction.

Intraneural recording in skin fascicles of the left ulnar nerve was performed in a 51 year old patient with reflex sympathetic dystrophy (allodynia, marked vasoconstriction in the ulnar part of the left hand) following Vth finger amputation. Skin sympathetic activity showed normal characteristics with a weak discharge at rest whereas bursts of impulses could be evoked by sympatho-excitatory stimuli. Sympathetic bursts induced by painful stimuli were few, also during long-lasting allodynic pain. Sympathetic bursts induced by inspiratory gasps were not associated with excacerbation of pain. The discrepancy between the marked skin vasoconstriction and the low resting sympathetic discharge underlines the fact that sympathetic effector organ hyperactivity (i.e. vasoconstriction and/or hyperhidrosis) cannot be taken as evidence for increased sympathetic discharge. In the present case, the neuropathic pain syndrome cannot be considered as maintained by an increased sympathetic neural discharge to the symptomatic limb.     

Clinical features of algodystrophy: is the sympathetic nervous system involved?

There is a spectrum of conditions which have in common burning pain, often with hyperpathia, hyperalgesia, vasomotor and sudomotor changes. When due to major nerve damage, the condition is known as causalgia; when due to minor nerve damage or other factors, various terms such as algodystrophy or reflex sympathetic dystrophy are employed. Radiography and isotopic bone scanning may be helpful investigations, and procedures which interrupt the local sympathetic nervous system are those most likely to help the pain. The classical view that the peripheral sympathetic nervous system is involved in generation of pain is questioned, and the possible roles of the central nervous system and of non-adrenergic mechanisms are summarised. That pain could be due to dysfunction of the polymodal nociceptor neurone is considered.     

Reflex sympathetic dystrophy induced by shunt malfunction: a case report]

A 60-year-old male presented with normal pressure hydrocephalus following subarachnoid hemorrhage and underwent a shunt operation. However, a shunt effective range was so narrow that he repeated a sign of overdrainage and underdrainage of CSF. At the result, reflex sympathetic dystrophy (RSD) as a complication of overdrainage was demonstrated. We could prescribe appropriate shunt flow rate by using siphon control system instead of antisiphon device (ASD) and then avoid shunt malfunction. In addition, medication of Neurotropin for pain control of RSD was so effective. We report a case of RDS as a complication of shunt malfunction.     

Clinical aspects of multifocal or generalized tonic dystonia in reflex sympathetic dystrophy.

The authors describe 10 patients with reflex sympathetic dystrophy that progressed to a multifocal or generalized tonic dystonia. The neuropsychologic profile was similar to that of other patients with chronic pain, irrespective of its cause. The distribution pattern of dystonia, the stretch reflex abnormalities, and the worsening of dystonia after tactile and auditory stimuli suggest impairment of interneuronal circuits at the brainstem or spinal level. Antibody titers for glutamic acid decarboxylase, tetanus, and Sj?gren antigens were all normal.     

Algodystrophy: treatment

Treatment of reflex sympathetic dystrophies involves early reduction of the nociceptive input, transient interruption of the sympathetic activity, modulation of central mechanisms of pain control, prevention of neurotrophic changes and treatment of associated behavioural problems. The fundamental steps are early control of pain by means of local anesthetic blocks and antiinflammatory agents followed by sympathetic blocks, physical therapy, transcutaneous electrical stimulation and supportive psychotherapy. The results obtained are not always satisfactory and about 40% of the patients is not susceptible to cure. The best results are obtained when treatment is started early.