Multifocal acquired demyelinating sensory and motor neuropathy: report of a case and review of the literature

Multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy is characterized by an asymmetric multifocal pattern of motor and sensory loss, and conduction block and other features of demyelination in nerve conduction studies. MADSAM neuropathy needs to be differentiated from chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN). In classic CIDP, there are symmetric proximal and distal weakness, sensory deficit in both upper and lower extremities and reduced deep tendon reflex. In MMN, limb weakness without sensory loss is asymmetric in the distribution of individual peripheral nerves and the weakness typically begins in the distal upper extremities. We report one patient with chronic progression of asymmetric numbness and weakness in four extremities. MADSAM neuropathy was diagnosed after extensive clinical and laboratory evaluations. It is very important to distinguish between CIDP, MADSAM neuropathy, and MMN by clinical, laboratory, and histological features because of different effective therapeutic strategies.     

Multifocal motor neuropathy: Electrodiagnostic features

Diagnosis of multifocal motor neuropathy (MMN), a syndrome characterized by progressive asymmetric weakness with intact sensation, is important because the disorder often responds to treatment. Multifocal partial motor conduction block (PMCB) has been emphasized as a cardinal feature in the diagnosis of this syndrome, but detailed nerve conduction studies are not available. Nine patients, ages 28–58, had chronic, progressive, asymmetric, predominantly distal limb weakness for 5–18 years. Sensation was normal and reflexes were reduced asymmetrically. Although all 9 demonstrated PMCB localized to short nerve segments, additional features of multifocal motor demyelination were present, including temporal dispersion (5 patients), segmentally reduced motor nerve conduction velocity (7 patients), prolonged distal motor latency (4 patients), and prolonged F-wave latency (9 patients). The strength of all patients improved after treatment with human immune globulin. A reduction in the degree of PMCB or an increase in the distal motor amplitude or both accompanied the clinical improvement. These studies suggest that patients with MMN demonstrate widespread evidence of motor demyelination in addition to the well-described PMCB, and that reduction of PMCB accounts for the increase in strength following therapy. © 1994 John Wiley & Sons, Inc.     

Two cases with chronic inflammatory demyelinating polyneuropathy showing high signal and enlargement of the brachial plexus in short TI inversion recovery of MRI]

We reported valuable MRI findings of the brachial plexus seen in two cases with chronic inflammatory demyelinating polyneuropathy (CIDP). Case 1 was a 44-year-old man who developed slowly progressive weakness and atrophy of the extremities with no sensory disturbances. Studies of CSF showed a normal level of protein and no increase of cell counts but nerve conduction studies demonstrated a significant conduction block between the axilla and the elbow in the right ulnar nerve. Case 2 was a 34-year-old male who had been suffering from distal limb weakness and sensory disturbance. Protein content in CSF was markedly elevated without pleocytosis, and nerve conduction studies revealed a conduction block between the elbow and the wrist in the right ulnar nerve. He received corticosteroid therapy, resulting in a good recovery. Brachial plexus in both cases showed enlargement with marked high signal on short TI inversion recovery (STIR) of MRI. STIR is a fat suppressed T2 weighted image and this technique is known to be useful to identify the morphology of peripheral nerve tissues. CIDP is one form of hypertrophic neuritis and the MRI findings seen in these two cases strongly support the diagnosis of CIDP.     

Acute-onset painful upper limb multifocal demyelinating motor neuropathy

We report three patients who presented with acute onset of shoulder and upper arm pain followed within a few days by predominantly distal upper limb weakness. Nerve conduction studies showed severe and unequivocal focal motor conduction block in the forearm and/or upper arm along with slowing of motor conduction and prolonged F wave responses. Only very mild changes in sensory nerve conduction were found. One patient made partial clinical improvement after 17 months, and there was a significant improvement in the degree of motor conduction block and the motor conduction velocities. A second patient remained unchanged after 5 months. Idiopathic brachial neuritis (IBN) typically presents acutely with brachialgia and acute or subacute non-progressive weakness. Multifocal motor conduction block in nerves in the arm or forearm has not been described in patients with IBN. Multifocal motor conduction block restricted to the upper limbs has been described in focal chronic inflammatory demyelinating polyneuropathy (CIDP) and in multifocal motor neuropathy with multifocal motor conduction block (MMNCB). However, both these conditions have hitherto usually been described as largely painless chronic progressive disorders with a subacute onset. Our patients, with features overlapping MMNCB/CIDP and IBN, represent an as yet unreported clinical variant. Received: 9 February 2000 / Received in revised form: 18 May 2000 / Accepted: 28 June 2000     

Sympathetic skin response in monomelic amyotrophy

OBJECTIVES: Monomelic amyotrophy (MMA) a variant of motor neuron disease, has the characteristic features of wasting and weakness usually confined to a single upper or lower limb occurring predominantly in young males and a benign outcome. Symptoms of increased sweating, coldness and cyanosis have been observed in a few patients. The objective was to evaluate the involvement of the sympathetic nervous system in MMA by measuring sympathetic skin response. METHODS: Electromyography, motor and sensory nerve conduction studies were done in all the four limbs of 9 patients with atrophy of one upper limb. Stimulation at Erb's point, and above and below elbow was done to look for evidence of conduction block. The sympathetic skin response (SSR) was recorded in all the limbs of these patients. Wasting and weakness of right upper limb in 7 patients and left upper limb in 2 patients was seen. The mean age was 28.3+/-10.1 years. Twenty-five age matched (24.8+/-4.8 years) healthy subjects served as controls. RESULTS: The mean SSR latency in the affected upper limbs of 9 patients was prolonged compared to the 25 control subjects (1.51+/-0.07 s vs 1.42+/-0.19 s, P=0.03). The mean value of SSR latency in 18 upper limbs of the 9 patients which included atrophied and unatrophied limbs was also prolonged compared to the controls (1.50+/-0.08 s vs 1.42+/-0.19 s, P=0.05). There was no significant difference of the mean latency of SSR between the atrophied upper limbs and the clinically normal upper limbs (1.51+/-0.07 s vs 1.49+/-0.09 s, P=0.51). The mean SSR latency in the lower limbs of the patients (2.09+/-0.09 s) did not significantly differ from the control subjects (1.97+/-0.28 s, P=0.09). Motor and sensory nerve conduction was normal and there was no evidence of conduction block. CONCLUSION: In MMA the sympathetic nervous system is involved in the atrophic upper limb and also in the clinically unaffected upper limb but not in the lower limbs.     

A case of malignant thymoma associated with Eaton-Lambert-type neuromuscular transmission block and sensorimotor neuropathy

The patient is a 73-year-old male. In January 1988, he noticed sensory disturbance and muscular weakness of his extremities. His thymoma was found in July 1988, and in October 1988, he was admitted to our hospital for treatment. Neurological examination showed muscular weakness, muscular atrophy, fasciculation, and distal dominant sensory disturbance of his right upper extremity and his bilateral lower extremities. The immunological examination showed an increase in serum IgG, gamma-globulin, OKT3 and OKT4 lymphocytes. Electromyographic studies showed severe waxing by repeated stimulations (200% by 10 Hz; 330% by 20 Hz), very low M wave amplitude by single stimulation, and post-tetanic exhaustion. An Eaton-Lambert-type neuromuscular transmission block was thus thought to exist. Concentric needle electromyography showed a neurogenic pattern. The sensory and motor nerve conduction velocity was delayed. Microscopic examination of biopsied skeletal muscle showed neurogenic change. A sural nerve biopsy specimen showed a decrease in the number of myelinated fibers (fiber density 4333/mm2), segmental demyelination, remyelination, and mild axonal change. Thymectomy was performed and pathological examination showed invasive thymoma of predominantly the epithelial type. His muscular weakness and sensory disturbance improved gradually after thymectomy. On the postoperative immunological examination, serum IgG, gamma-globulin, OKT3 and OKT4 lymphocytes were normalized. On the other hand, OKT8 lymphocytes were increased and the OKT4 to OKT8 ratio was decreased. The electromyographic studies showed no waxing, normal M wave amplitude, and no post-tetanic exhaustion. Therefore, we consider that an Eaton-Lambert-type neuromuscular transmission block and sensorimotor neuropathy in this case were caused by the immunological abnormality accompanying malignant thymoma.     

Two distinct types of neuropathy associated with Sj?gren's syndrome developed in one patient. The importance of the selection of an appropriate therapeutic regimen]

A 62-year-old woman was admitted to our hospital because of muscle weakness and sensory disturbance in extremities. She showed weakness, muscle atrophy and sensory abnormality in four limbs with patchy distribution, suggesting involvement of multiple peripheral nerve trunks. Serum titers of anti-SS-A, SS-B, and antinuclear antibody were elevated. Sural nerve biopsy showed recanalization and lymphocytic infiltration in the epineural small vessels, suggesting the presence of vasculitis. She was diagnosed as having vasculitic neuropathy complicated with Sj?gren's syndrome. Methylprednisolone pulse therapy followed by oral prednisolone was started and these symptoms gradually improved in one month. At age 63, she felt dysesthesia in the right lower limb and this sensory abnormality spreaded to upper limbs. Two years later, she was admitted again due to clumsiness of hands and gait disturbance. Neurological examination showed decreased vibration and position sense of lower limbs and limb ataxia in addition to dysesthesia. Electrophysiological studies demonstrated significant decrease in amplitude of sensory nerve action potentials and delayed somatosensory evoked potentials after N13, indicating impairment of dorsal root ganglions. She was treated with intravenous immunoglobulin (400 mg/kg, total 15 g/day) for 5 days. One week later, sensory ataxia was improved. It has been known that Sj?gren's syndrome is often complicate with various types of neuropathies including vasculitic neuropathy and sensory neuropathy. Our patient developed these two different types of neuropathies which were dramatically improved after two different therapeutic regimens; indicating the importance to select a suitable treatment regimen in accordance with the mechanism of neuropathy associated with Sj?gren's syndrome.     

A case of distal lower motor neuron syndrome associated with IgM anti-GM1 antibodies

A 34-year-old man had noted progressive weakness in his right hand. On admission at age 39, cranial nerves were not involved. Fasciculations were observed in his upper limb girdles. Neurological examination revealed severe wasting and weakness of arms and the right hand, whereas mild in the left hand. The deep tendon reflexes were absent in the upper extremities, but normal in the lower extremities. No sensory disturbances were observed. Motor and sensory nerve conduction velocities were normal, and multifocal conduction block was not observed. EMG showed neuropathic changes in all 4 limbs and sternocleidomastoideus muscles. Serum immunoelectrophoresis failed to detect an M protein. High-performance thin-layer chromatography with immunostaining revealed that his serum IgM reacted with GM1, but not reacted with GM2, GD1a, GD1b, and asialo-GM1.     

Cervical nerve root stimulation. Part II: findings in primary demyelinating neuropathies and motor neuron disease.

OBJECTIVE: Cervical nerve root stimulation (CRS) allows the assessment of conduction in the proximal segments of motor fibers destined to the upper extremities, which are not evaluated by routine nerve conduction studies (NCS). Since many primary demyelinating polyneuropathies (PDP) are multifocal lesions may be confined to the proximal nerve segments. CRS may therefore increase the yield of neurophysiologic studies in diagnosing PDP. METHODS: We reviewed clinical and neurophysiologic data from 38 PDP patients and compared them to 35 patients with motor neuron disease (MND), and 21 healthy controls (HC). RESULTS: Mean onset-latency was significantly prolonged in PDP patients. The optimal onset-latency cutoff necessary to distinguish PDP from MND and controls was 17.5 ms for the abductor pollicis brevis (APB) and abductor digiti minimi (ADM), and 7 ms for Biceps and Triceps. Mean reduction in proximal to distal CMAP amplitude to APB and ADM was significantly greater in PDP patients, with an optimal cutoff in proximal to distal CMAP amplitude reduction necessary to distinguish PDP from MND and HC being 45%. CONCLUSIONS: CRS is effective in distinguishing PDP from MND and HC based on prolonged onset latency and conduction block criteria. SIGNIFICANCE: CRS may increase the diagnostic yield in cases where demyelinating lesions are confined to the proximal peripheral neuraxis.     

Sensori-motor neuropathy associated with congenital bilateral club feet: histological and ultrastructural study of the sural nerve

A 53-year-old female with sensori-motor neuropathy associated with bilateral club feet was reported. She was admitted because of numbness in the bilateral feet and gait disturbance. Her parents were not related. There was no family history of any neurological diseases. She had bilateral club feet which were present at birth to developed in early childhood. She could walk, but could not run. Since 5 years prior to the admission she noted gradually increasing disturbance of gait. Neurological examination revealed muscular weakness and wasting in the distal parts of the lower extremities and decreased deep tendon reflexes. There were hypesthesia, hypalgesia and dysesthesia in the lateral portions of the bilateral feet. Deep sensation was normal. There was no weakness or wasting in the upper extremities. Motor nerve conduction velocities were normal and sensory nerve conduction velocities were reduced in the median nerve. No action potentials could not be elicited in the bilateral tibial and peroneal nerves. A sural nerve biopsy showed a markedly hypertrophic perineurium, 28-150 micron thick, a large Renaut body measured 140 micron by 200 micron in diameters and a markedly reduced number of the myelinated fibers. Fiber size histogram showed many unmyelinated fibers larger than 1 micron, despite loss of fibers of the usual size. Therefore, a part of the unmyelinated fibers might be demyelinated. There were no axonal degeneration and onion-bulb formation. Segmental demyelination was found in approximately 30% of the myelinated fibers.(ABSTRACT TRUNCATED AT 250 WORDS)     

Multifocal motor neuropathy with conduction block with sensory fibre involvement in a diabetic patient. Case report

Multifocal motor neuropathy with conduction block (MMNcb) is a relatively rare disease characterized clinically by asymmetric limb weakness with spared sensation and electrophysiologically by persistent focal motor conduction block. We present the case of a 40-year-old male patient with six-year history of progressive, asymmetric weakness of upper and lower extremities without sensory symptoms. Electroneurography revealed definite or probable motor conduction block in several nerves. However, features of axonal lesion of sensory fibres were also found. Laboratory studies were unremarkable apart from an abnormal glucose tolerance test, and type 2 diabetes was diagnosed. In the presented case the differential diagnosis should take into consideration MMNcb with coexisting diabetic sensory polyneuropathy and multifocal acquired demyelinating sensory and motor neuropathy (MADSAM).     

Peripheral neuropathy in Tangier disease: A literature review and assessment

Tangier disease (TD) (OMIM#205400) is a rare cause of inherited metabolic neuropathies characterized by marked deficiency of high‐density lipoproteins and accumulation of cholesterol esters in various tissue resulting from reverse cholesterol transport deficiency. We report a case of a patient with TD with multifocal demyelinating neuropathy with conduction block who presents with winging scapula, tongue, and asymmetric extremity weakness. We also present a review of all studies published from 1960 to 2017 regarding peripheral neuropathy in TD. Our search identified 54 patients with TD with peripheral neuropathy. Syringomyelia‐like neuropathy subtype (52.4%) was more frequent than multifocal sensorial and motor neuropathy subtype (26.2%), focal neuropathy subtype (19.1%), and distal symmetric polyneuropathy subtype (2.4%). Splenomegaly was the most common (40.7%) clinical manifestation in these patients. The pattern of electrodiagnostic abnormalities are: (1) demyelinating abnormalities were more predominant in the upper extremities than in the lower extremities and (2) slowing of motor nerve conduction was more prominent in the intermediate segment than in distal nerve segments. The sural‐sparing pattern was present in 34.6% and conduction block was present in 11.5% of the patients. Our literature review and our case showed the clinical spectrum of TD neuropathy is quite wide and that it should be considered in the differential diagnosis of non‐uniform demyelinating neuropathies.     

Nitrous oxide: clinical and electrophysiologic investigation of neurologic complications

Prolonged exposure to nitrous oxide produces a recognized neurologic syndrome. We report clinical and electrophysiologic studies of nervous system involvement in a 25-year-old student who abused nitrous oxide. He developed signs of a sensorimotor polyneuropathy and of myelopathy. Routine blood studies, CSF examination, and myelogram were normal. Clinical electrophysiologic studies were performed serially. Nerve conduction studies demonstrated reduced amplitude and slowed sensory potentials, and mildly prolonged late responses. Sensory evoked potentials revealed prolonged latency of scalp-evoked potentials from tibial nerve stimulation with normal median nerve values. The foveal visual evoked potential was delayed in the right eye, with normal visual acuity, funduscopic examination, and spatial contrast sensitivity. Repeat electrophysiologic studies demonstrated improvement. Nitrous oxide produces multifocal reversible dysfunction within the nervous system similar to that described in patients with vitamin B12 deficiency.     

A patient of sensorimotor neuropathy with small cell lung carcinoma and anti-GM1 antibody]

We reported a 62-year-old woman had sensorimotor neuropathy with small cell lung carcinoma (SCLC) and anti-GM1 antibody. She was admitted with several months history of progressive numbness, walking disturbance and anorexia. Neurologic examination revealed severe numbness and deep sensory disturbance of extremities and body, and mild weakness of distal extremities. Deep tendon reflexes were absent. Her limbs were ataxic. Nerve conduction studies showed no sensory evoked responses. CSF protein was elevated. Sural nerve biopsy revealed severe loss of myelinated fibers and perivascular mononuclear cells surrounding the perineurial vessel. Vasculitic neuropathy was diagnosed, and prednisolone was started, with no benefit. In the clinical course, she developed cough attacks and was found the lymphnode swelling in the mediastinum and supraclavicular fossa, which was diagnosed SCLC. Although anti-Hu antibody were not detected, anti-GM1 antibody was positive. She was treated with intravenous immunoglobulin, with transient improvement. The rare case of the paraneoplastic peripheral neuropathy with SCLC and anti-GM1 antibody was reported.     

A case of mitochondrial myopathy with mononeuritis multiplex

A case of mitochondrial myopathy with mononeuritis multiplex was described. A 55-year-old man was hospitalized because of blepharoptosis and muscle weakness. His mother also showed blepharoptosis in her elderly stage of life. He had been healthy until 46 years of age, when he first noticed difficulty of speech, followed by bilateral blepharoptosis, weakness of upper limbs, and sensory disturbance in the left occipital, and left upper and lower extremities. These symptoms progressed slowly. On admission, bilateral blepharoptosis was recognized. Slightly to moderate muscle wasting and weakness were observed in the face, neck, trunk, and extremities. Areflexia was observed in the upper extremities. Paresthesia was observed in the left occipital and left hip, and superficial sensation was impaired in the left upper and lower extremities. Electromyographic examination of extremities showed neurogenic changes in the distal muscles and myogenic changes in the proximal muscles. Motor conduction velocities were normal, but sensory conduction velocities decreased in amplitude on the left upper extremity and were not evoked on the left lower extremity. Muscle biopsy specimen revealed numerous "ragged-red" fibers. Cytochrome c oxidase stain showed a decrease in intensity of staining. A sural nerve biopsy showed slight axonal degeneration and slight loss of nerve fibers. Biochemical analysis on biopsy muscle showed partial deficiency of cytochrome c oxidase activity.     

A case of mortor neuron syndrome with onset 9 months after electrical injury]

A 72-year-old man noticed progressive weakness of both upper limbs, more severe on the left side, 9 months after an electric shock of a 20,000 V alternating current. He had diffuse scars of superficial burns with skin graft in four limbs, more on the right side. A neurological examination revealed diffuse muscle atrophy, weakness and fasciculation in both upper limbs, predominantly on the left side, hyper-reflexia in four limbs with mildly exaggerated jaw jerk, left Babinski sign, and mild decrease of touch and pain sensation in the right C6 and C7 segments. Painful dysesthesia was present in the left hand and right lower limb. The search for serum antibodies against GM1, GM2, GM3, GD1a, Gd1b, GQ1b, GA1, and GT1b was negative. No abnormality except mild cervical spondylotic changes was evident in the magnetic resonance imaging of the brain and spinal cord. The upper limb motor evoked potentials (MEPs) were not elicited by the left cortical stimulation and the central motor conduction time by the right cortical stimulation was remarkably prolonged in the upper limb MEPs. Nerve conduction study showed a delay of motor conduction velocity and distal latency in the right median and bilateral ulnar nerves with low amplitude and delayed velocity of sensory nerves of those nerves. Needle EMG revealed diffuse ongoing denervation potentials in bilateral upper limbs and giant motor unit potentials in the right triceps and first dorsal interossei muscles. These findings indicate that the delayed motor neuron syndrome induced by electrical shock is characteristic for having demyelination as well as axonal changes in both central and peripheral nervous systems.     

Multifocal axonal motor neuropathy associated with anti-ganglioside antibodies]

We report a patient with asymmetrical patchy weakness of the limbs, and with autoantibodies against gangliosides GM1, GD1b, asialo GM1. Although electrophysiological studies did not reveal conduction block, treatment with prednisolone resulted in clinical improvement. A 52-year-old man was admitted to Kyoto University Hospital, because of gait disturbance. Neurological examination revealed a patchy distribution of weakness in the limbs. Deep tendon reflex was normal at the right knee, and was depressed at the right biceps. Other deep tendon reflexes were absent. There was a slight decrease in vibratory sensation in the distal portions of the lower extremities. Routine laboratory studies, heavy metal screen, vitamin, cryoglobulin, coproporphyrin and delta-amino levulinic acid in urine, and the protein value of the cerebrospinal fluid were normal. Head and neck MRI, and myelography were normal. Immunofixation electrophoresis showed IgM lambda M-protein in serum. Thin-layer chromatography with immunostaining showed his serum IgM reacted with GM1, GD1b, and asialo GM1. ELISA (Enzyme Linked Immunosorbent Assay) demonstrated high titers of anti GM1, GD1b and low titer of anti asialo GM1. Motor conduction studies showed no demonstrable conduction block, normal conduction velocities and the low amplitudes of CMAP. Sensory conduction studies showed no abnormalities except for slightly decreased amplitude of SNAP in sural nerve. Electromyography showed active denervation in extensor digitorum communis muscle, tibialis anterior muscle and left biceps brachii muscle. Muscle biopsy specimen revealed large and small group atrophy and there was perivascular mononuclear infiltration at one point.(ABSTRACT TRUNCATED AT 250 WORDS)     

Primary progressive multiple sclerosis as a differential diagnosis of ALS: a case report]

A 44-year-old man was admitted to our hospital because of a five year history of chronic progressive gait disturbance. Neurological examination revealed mild weakness and atrophy of the upper extremities, but severe of the lower ones, and without sphincter disturbance or apparent sensory impairment. Hyperreflexia and positive pathological reflexes of the lower extremities were apparent. EMG showed a reinnervation pattern and decreased number of motor units in the extremities, suggesting ALS. However, multiple plaques on the head and spinal MRI, a prolonged central conduction time of MEP and SEP, a delayed P100 latency of VEP, and a increased IgG index in the CSF indicated primary progressive type multiple sclerosis. After receiving steroid pulse therapy, the weakness of the lower extremities showed slight improvement. Diffuse inflammation in the spinal cord involving not only the pyramidal tract but also the anterior horn cells/intramedullary ventral roots explained the ALS-like clinical picture.     

A case of sarcoid polyradiculopathy with nerve roots swelling demonstrated by myelography]

A 62-year-old woman was admitted to our hospital because of tingling numbness in the trunk and upper extremities. She was well until 18 days earlier, when she began to feel tingling numbness on the ulnar side of the left arm. During the next two weeks it spread gradually over the trunk and ulnar side of the bilateral arms. She had also progressive difficulty in taking hold of objects. On neurological examination she was alert and cooperative with normal articulation. The neck was supple. The cranial nerves were intact. Superficial sensation was bilaterally hypesthetic in the distribution from the 7th cervical through 12th thoracic segments. Mild weakness was distally noted in the upper extremities. Deep tendon reflexes were reduced or absent without laterality. Plantar responses were bilaterally flexor. Coordination and gait were normal. Routine laboratory examinations including blood counts, blood chemistries and urinalysis were unremarkable. Serum angiotensin converting enzyme (ACE) was slightly elevated. A lumbar puncture yielded clear, colorless cerebrospinal fluid (CSF) containing 22 white cells/mm3 and protein of 106 mg/dl. Conventional nerve conduction studies were normal. F-wave conduction studies revealed elevated F-ratios for the upper and lower extremities. Studies of short-latency somatosensory evoked potential showed mild prolongation of N13 recorded after stimulation of the right median nerve. An X-ray film of the spine was unremarkable except for mild narrowing of the C5-6 intervertebral disk space. Postcontrast magnetic resonance imaging of the spine with gadolinium-DTPA was unrevealing as well as a precontrast study. A myelogram disclosed enlarged lateral filling defects corresponding to cervical nerve roots from C6 through C8 bilaterally.(ABSTRACT TRUNCATED AT 250 WORDS)     

Acute compression neuropathy of the proximal sciatic nerve in a patient with facioscapulohumeral muscular dystrophy]

We reported a 58-year-old man with facioscapulohumeral muscular dystrophy who had acute compression neuropathy of the sciatic nerve after prolonged sitting position. MRI and percutaneous electric stimulation studies were usefull for the diagnosis. Gd-DTPA T1-weighted MRI images showed the enhanced right sciatic nerve at the level of gluteus maximus muscle. An evoked potential study by a percutaneous electric stimulation revealed evidence of a conduction block at the same level. After methylprednisolone pulse therapy, muscle weakness and sensory disturbance improved. Acute compression neuropathy of the sciatic nerve may be seen as a complication in the advanced stage of (FSH) muscular dystrophy.