Scapuloperoneal neuropathy: a distinct clinicopathologic entity

Peripheral neuropathy as a cause for the scapuloperoneal syndrome continues to be controversial. This report provides further evidence in support of a scapuloperoneal neuropathy as a separate nosologic entity. Three men had a slowly progressive disorder of 5-17 years duration with prominent weakness and atrophy of scapular stabilizer, shoulder girdle and distal lower extremity muscles accompanied by a distal pan-modality sensory loss. Electrodiagnostic studies and sural nerve biopsies indicated a primary axonal neuropathy with secondary demyelination and remyelination.     

Scapuloperoneal atrophy with sensory involvement: Davidenkow''s syndrome.

A patient with scapuloperoneal atrophy of neurogenic type, in whome there was also distal sensory impairment, has been studied with conventional EMG, single fibre EMG, and muscle biopsy. This disorder, described by Davidenkow, may be a distinct entity.     

Zur Differentialdiagnose der scapulo-peronealen Amyotrophie

Zusammenfassung Es wird über ein scapulo-peroneales Syndrom berichtet, dessen regellose, schubweise Entwicklung über Jahre von Schmerzen, distal betonten Paraesthesien sowie Hypaesthesien im Bereich der Hände und Unterschenkel begleitet wurde. Asymmetrische Paresen und Atrophien betreffen besonders den Schultergürtel sowie Fuß- und Zehenextensoren, wohingegen die Beuger verschont sind.Nach klinischem Befund, elektromyographischen und -neurographischen Untersuchungen sowie den Ergebnissen der Muskel- und Nervenbiopsie (N. suralis) wird das Syndrom in die Gruppe des Dawidenkowschen Typs der scapulo-peronealen Amyotrophie mit autosomal dominantem Erbgang eingeordnet.Auf differentialdiagnostische Fragen, die sich aus der Kombination des myopathischen Prozesses mit polyneuropathisch begrenzten Sensibilitätsstörungen und Reflexabschwächung ergeben, wird anhand ähnlicher Beobachtungen in der Literatur eingegangen.

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The differential diagnosis of scapuloperoneal amyotrophy

Summary This report deals with a scapuloperoneal syndrome which developed simultanously with pain and distal paresthesias. In addition there was a slight sensory disturbance of glove and stocking type distribution. Motor conduction velocity was within normal limits and all distal latencies of response were normal; only the sensory conduction velocity of the left median nerve was found to be decreased (42.1 m/s). Electromyographic investigations revealed only signs of myopathy.Histological findings (m. deltoideus, m. tibialis anterior) favoured a primary myopathic process. Biopsy of the n. suralis revealed no certain pathological changes. The affection appears to have an autosomal dominant mode of inheritance.The sensory disturbance and decreased reflexes indicate an involvement of the nervous system, but the question of relationship to the scapuloperoneal muscular atrophy cannot yet be answered.

     

Sensory signs and symptoms in scapuloperoneal atrophy: a report of a family

A Norwegian family with asymmetrical scapuloperoneal atrophy is described. Chronic, aching shoulder pain, slight proximal and distal sensory dysfunction, and atrophy of the extensor digitorum brevis muscle occurred in some individuals. The proband had slightly impaired sensory conduction velocity, and his father exhibited impaired position sense and a vibration threshold asymmetry. EMG and muscle biopsy findings were equivocal. The syndrome is probably of neurogenic origin. It may be classified as a variant of Davidenkow's syndrome.     

Chronic distal spinal amyotrophy or spinal forms of Charcot-Marie disease. A report on six sporadic adult cases (author's transl)

Based on a personal series of 6 cases, and about 20 cases reported in the published literature, the authors describe the principal characteristics of chronic distal amyotrophy of spinal origin: early onset or in young adults, initial disorder in lower limbs, especially anterolateral region of the legs, with secondary lesions in small muscles of the hands, absence of sensory disturbance, usually very slow progression, electrophysiological appearance of chronic denervation with normal conduction velocities, and neurogenic muscle lesions with unaffected peripheral nerve. These forms can be compared to the "spinal" forms of Charcot-Marie-Tooth disease and appear to be degenerative in origin even though proof by autopsy is lacking. In spite of their common characteristics, however, their genetic heterogenicity has to be noted: sporadic cases are seen most frequently but some cases are related to recessive autosomic transmission and others to dominant autosomic transmission. From the clinical point of view, some cases are distinctive in that there is early or predominant atrophy in the lower limbs, while others have lesions in muscles of bulbar innervation, which is against their origin from spinal amyotrophy. Finally, electrical signs at a distance from the atrophied muscles suggest extension of the pathological process. In spite of these comments, the authors suggest that the clinical concept of the distal form of spinal amyotrophy should be retained together with the proximal and scapuloperoneal forms.     

A large New England kindred with autosomal dominant neurogenic scapuloperoneal amyotrophy with unique features.

We describe a large New England kindred bearing an autosomal dominant syndrome of neurogenic amyotrophy with variable expression. Features include congenital absence of muscles, progressive scapuloperoneal atrophy, laryngeal palsy, and progressive distal weakness and atrophy. The pattern of expression and progression varies in different branches of the family. Males are more severely affected than females. Disease expression is more severe and progressive in succeeding (third and fourth) generations. This striking increase in severity and progressivity in succeeding generations may have genetic implications. The syndrome most resembles the Stark-Kaeser chronic scapuloperoneal amyotrophy, but is considered a distinct entity.     

Adult acid maltase deficiency

A 30-year-old man was referred for neurologic evaluation because of elevated creatine kinase. He had noted symptoms of proximal arm and distal leg weakness for several years, and, on examination, he had weakness in a scapuloperoneal distribution. An electromyogram showed myotonic discharges in the paraspinous muscles, and a muscle biopsy revealed severe vacuolar myopathy. Biochemical analysis of muscle showed acid maltase deficiency. The patient's only brother had childhood-onset acid maltase deficiency and died of respiratory failure at age 27. Acid maltase deficiency may have heterogeneous presentations within a family, and adult AMD can present as a scapuloperoneal neuromuscular syndrome. © 1993 John Wiley & Sons, Inc.     

Adult-onset autosomal recessive neurogenic scapuloperoneal syndrome

We report a brother and sister who showed weakness, atrophy and fasciculations starting in adulthood, predominantly affecting the muscles of the shoulder girdles and distal lower extremities. Mild ptosis and facial weakness were present in both. Electrophysiological studies and muscle histology supported a neurogenic basis for the autosomal recessive scapuloperoneal syndrome in this sibship.     

Gracile tract degeneration in patients with sensory neuropathy and AIDS

At autopsy, four homosexual men with acquired immunodeficiency syndrome (AIDS) were found to have selective degeneration of the gracile tract, a finding previously unreported in AIDS. Clinically, these patients had progressive lower extremity paresthesias and dysesthesias with reduced or absent ankle jerks, and eventually they developed dementia. Postmortem examination of spinal cords showed a striking loss of both axons and myelin sheaths confined to the fasciculus gracilis, with the most severe involvement in upper thoracic or cervical segments. Lumbar dorsal columns showed only a mild fiber loss, and no fiber loss was observed in lumbar dorsal roots. Lumbar dorsal root ganglia were available from one patient and showed a mild sensory ganglionitis. In all cases examined, microglial nodules were present in the brain. In 23 other individuals with AIDS who had autopsies consecutively with these four subjects, none had sensory neuropathy and the gracile tracts were normal. The combination of distal sensory neuropathy and gracile tract degeneration suggests a "dying-back" process of dorsal root ganglia neurons.     

Tibial muscular dystrophy. A rare form of distal myopathy]

Tibial muscular dystrophy (TMD) is a dominantly inherited late onset distal leg myopathy only described in the Finnish population as yet. A similar disorder was described by Markesbery et al. in 1974 in one American family. Assignment of the TMD locus to chromosome 2q31 has been demonstrated (Haravuori et al., 1998). We recently described a French family with clinical and laboratory findings similar to TMD (de Seze et al., 1998). Molecular genetic results indicate that the distal myopathy in this family could be linked to the TMD locus confirming TMD exists outside the Finish population. This overview of TMD will allow to describe differential diagnoses such as other distal myopathies and scapuloperoneal syndromes.     

Scapuloperoneal muscular dystrophy phenotype due to TRIM32-sarcotubular myopathy in South Dakota Hutterite

Scapuloperoneal muscular dystrophy is a group of genetically heterogeneous disorders that share the phenotype of progressive weakness of scapular and anterior distal leg muscles. Recessive mutations in C-terminal domains of TRIM32 result in limb-girdle muscular dystrophy 2H and sarcotubular myopathy, a rare congenital myopathy commonly seen in Hutterites. A scapuloperoneal phenotype has never been reported in sarcotubular myopathy. We here report a 23-year-old Hutterite man with a one-year history of progressive weakness predominantly involving the anterior tibial and left scapular muscles, and hyperCKemia. Biopsy of the anterior tibial muscle showed an active myopathy with non-rimmed vacuoles and mild denervation atrophy associated with reinnervation. The vacuoles are similar to those described in sarcotubular myopathy. TRIM32 sequencing revealed the common c.1459G>A mutation at homozygosity. A search for mutations in TRIM32 should be considered in patients with scapuloperoneal muscular dystrophy, and especially in patients of Hutterite origin or with an atypical vacuolar myopathy.     

A primigravida with very‐long‐chain acyl‐CoA dehydrogenase deficiency

Introduction: Valosin‐containing protein (VCP) is a ubiquitously expressed, multifunctional AAA‐ATPase protein. Its dominant mutations cause hereditary inclusion body myopathy associated with Paget disease of bone and frontotemporal dementia (IBMPFD) or amyotrophic lateral sclerosis. The pattern of muscle weakness in IBMPFD patients is variable and includes limb‐girdle, scapuloperoneal, distal, or axial distributions. Case Report: We report a 63‐year‐old man with progressive scapuloperoneal weakness, head drop, and hyperCKemia since age 40 years. Electromyography showed myopathic changes and rare myotonic discharges. Muscle biopsy revealed numerous lobulated fibers, few fibers with glycogen accumulation, and rare fibers with polyglucosan bodies. Rimmed vacuoles and congophilic inclusions, often seen in IBMPFD, were absent. VCP sequencing identified a novel heterozygous c. 1160G>A mutation resulting in p.Asn387Ser substitution. Conclusions: Our patient broadens the pathological spectrum of VCP‐myopathy and emphasizes the importance of VCP analysis in patients with scapuloperoneal muscular dystrophy despite the absence of Paget disease, dementia, rimmed vacuoles, or intracellular amyloid deposition. Muscle Nerve 50:295–299, 2014     

Cutaneous T-cell lymphoma mimicking myopathy with lipoatrophy

Mycosis fungoides (MF) is the most common form of primary cutaneous T-cell lymphoma. Classic MF usually follows a rather benign course over many years or decades, rarely ever leading to fatal extracutaneous organ involvement. Single cases of muscular involvement have been reported. Here we describe a 42-year-old male patient with hair loss and lipoatrophy since six months diagnosed as follicular MF and with a two months history of progressive distal leg weakness. Muscle biopsy and whole body muscle MRI showed an extensive muscular and subcutaneous fatty tissue infiltration. After therapy with topical steroids and acitretin/PUVA, systemic chemotherapy (CHOP) was initiated. The patient suffered from a rapid disease progression with fatal outcome 2.5 years after the first skin lesions, displaying progressive cachexia, muscular atrophy and weakness with scapuloperoneal distribution and cardiac dysfunction. So far, extensive muscular involvement by MF mimicking a distinct muscular phenotype has not been reported.     

Distal latency in motor neuron disease

In our investigation 24 patients suffering from spinal amyotrophy and 11 from amyotrophic lateral sclerosis were analyzed in order to determine the influence of these diseases on teh conduction velocity of the distal motor and sensory fibers. Both diseases belong to motor neuron diseases and are of unknown etiology. The conduction velocity was measured by using electroneurographic methods. Distal motor latency is expressed as a quotient of terminal latency that is obtained by dividing the distance between the stimulation and the registration point by the latency of response and was measured in cm/ms. It represents the conduction velocity of the distal motor fibers. Its sensory equivalent is the sensory conduction velocity S0-S1. In our work the mean values of distal motor and sensory latencies were counted and the correlation between them was examined. We also counted the percentage of the patients with the pathological values of these parameters. The results indicate that the "motor neurone disease" affects the conduction velocity of the distal motor and sensory fibers. The distal sensory latency was prolonged in higher percentage than the motor latency. Between motor and sensory latencies no correlation was found.     

Skin biopsy and quantitative sensory testing do not predict response to lidocaine patch in painful neuropathies

Predictors of response to neuropathic pain treatment in patients with painful distal sensory neuropathies are lacking. The 5% lidocaine patch is believed to exert its effects on neuropathic pain via a local stabilizing effect on cutaneous sensory afferents. As such, it provides a model to assess whether the status of epidermal innervation as determined by skin biopsy or quantitative sensory testing (QST) of small- and large-diameter sensory afferents might serve as predictors of response to topical, locally active treatment. In this study we assessed associations between epidermal nerve fiber (ENF) densities, sensory nerve conduction studies (NCS), QST, and response to a 5% lidocaine patch in patients with painful distal sensory neuropathies. We observed no association between distal leg epidermal and subepidermal innervation and response to the lidocaine patch. Several patients with complete loss of distal leg ENF showed a response to the lidocaine patch. Similarly we observed no consistent association between treatment response and QST for vibration, cooling, warm, heat-pain, and cold-pain thresholds, or distal sensory NCS. Thus, distal-leg skin biopsy, QST, and sensory NCS cannot be used to identify patients with painful polyneuropathy likely to respond to a lidocaine patch in clinical practice. Further studies are required to clarify precisely the mechanism and site of action of the lidocaine patch in patients with peripheral neuropathic pain.     

Peripheral neurophysiology of acute distal spinal cord infarction

F-wave abnormalities, in the presence of normal distal motor nerve conduction, most often are the first indicators of proximal peripheral nerve dysfunction in demyelinating polyradiculoneuropathies. However, a 15-year-old female-who developed lumbosacral spinal cord infarction with paraplegia, sensory loss, and incontinence beginning 15 hours after a fall-studied electrophysiologically at 2 days postparaplegia manifested absent lower-extremity f-waves and H-reflexes and normal compound muscle action potentials and distal motor and sensory conduction velocities. Subsequent evaluations demonstrated permanent loss of compound muscle action potentials, f-waves, and H-reflexes and prominent acute denervation in paralyzed lower-extremity muscles. Thus early f-wave and H-reflex loss can also occur in spinal cord disease, thereby representing the first evidence of motoneuron destruction.     

Deletions of chromosome 17p11.2 in multifocal neuropathies

We investigated 51 patients with multifocal neuropathies for the deletion of chromosome 17p11.2 described in families with hereditary neuropathy with liability to pressure palsies (HNPP). The deletion was detected in 24 patients, including 19 patients from 14 of 15 families in whom HNPP had been considered likely on clinical, neurophysiological, and/or pathological grounds. One patient with a deletion had rather unusual clinical features for HNPP, presenting with a progressive scapuloperoneal syndrome. Overall, 7 (37%) of the 19 index patients with the deletion had no affected relatives, and less than half had evidence of a generalized neuropathy on examination. Peripheral nerve lesions were related to pressure in only 15 (62%) of the patients with the deletion. Nerve conduction studies in 23 of 25 patients and relatives studied showed a fairly uniform pattern of moderate prolongation of distal sensory and motor latencies and slowing of conduction velocities, and variable reduction of sensory or evoked muscle action potential amplitudes. The patients investigated who did not have a deletion of 17p11.2 were heterogeneous and included those with recurrent and/or familial neuralgic amyotrophy, two or more peripheral nerve lesions at common sites of entrapment, or a patchy axonal neuropathy of unknown etiology. In 1 patient a diagnosis of HNPP remains most likely. DNA analysis for the deletion of 17p11.2 is clearly useful in establishing the diagnosis of HNPP, which should be considered regardless of family history or clinical evidence of a generalized neuropathy, and in patients with multifocal neuropathies that do not conform to the classic clinical picture of HNPP.     

Toxic polyneuropathy due to methyl n-butyl ketone. An industrial outbreak.

Cases of toxic distal polyneuropathy have been studied in a plant producing plastic-coated and color-printed fabrics. After the screenig of 1,157 employees, a total of 86 verified cases were detected. Of these, 11 were moderate to severe in intensity and usually with motor and sensory involvement; 38 were mild, with sensory signs prevailing; and 37 were minimal, but with characteristic electro-diagnostic abnormalities. Muscle weakness and electromyographic abnormalities were predominantly distal. Reflex loss was minimal. Sensory deficits were distal and limited to pain, touch, and temperature discrimination with occasional loss of vibration sense. The distribution of involvement severity of the disorder, and temporal course of the outbreak correlated with exposure with methyl n-butyl ketone. After elimination of this agent improvement was noted in the majority of cases.     

Prior collateral sprouting enhances elongation rate of sensory axons regenerating through acellular distal segment of a crushed peripheral nerve

Regenerating axons in crushed peripheral nerves grow through their distal nerve segments even in the absence of Schwann cell support, but their elongation rate is reduced by 30%. We examined whether prior exposure of sensory neurons to trophic factors achieved either by collateral sprouting or regeneration after conditioning lesion could enhance subsequent regeneration of their axons after crush, and compensate for loss of cell support. Collateral sprouting of the peroneal cutaneous sensory axons in the rat was evoked by transection of adjacent peripheral nerves in the hind leg. The segment of the peroneal nerve distal to the crush was made acellular by repeated freezing. Sensory axon elongation rate during regeneration was measured by the nerve pinch test. Prior axonal sprouting for two weeks increased the elongation rate of sensory axons through the acellular distal nerve segment back to normal value observed in control crushed nerves. The number of axons in the acellular distal segment at a fixed distance from the crush site was about 50% greater in sprouting than in control non-sprouting nerves. However, prior sprouting caused no further increase of axon elongation rate in control crushed nerves. Prior collateral sprouting, therefore, could in some respect compensate for loss of cell support in the distal nerve segment after crush lesion. This suggests that loss of cell-produced trophic factors is probably responsible for slower elongation rate through the acellular distal nerve segment. Surprisingly, prior conditioning lesion caused no enhancement of elongation rate of the sensory axons regenerating in the absence of cell support.