Polyphasic Motor Unit Potentials Research Articles

Bruns Garland Syndrome as the first presentation of type 2 diabetes: two case reports and a practical approach to diagnosis

BackgroundDiabetes is a global health problem causing a significant burden on the healthcare systems both due to the disease itself and associated complications. Diabetic radiculoplexus neuropathies or Bruns–Garland syndrome constitutes a rare form of microvascular complications, more commonly affecting the lumbosacral plexus and, very rarely, the cervical plexus. We describe two Sri Lankan males who presented with diabetic lumbosacral radiculoplexus neuropathy and diabetic cervical radiculoplexus neuropathy as the initial manifestation of diabetes.Case descriptionCase 1: a 49-year-old Sri Lankan hotel chef presented with subacute painful weakness and wasting of the left upper arm for 3 months and weight loss. Left upper limb proximal muscles were wasted with diminished power and reflexes. A nerve conduction study showed comparative amplitude reduction. An electromyogram revealed positive sharp waves, frequent fibrillations, and high amplitude polyphasic motor unit potentials with reduced recruitment in proximal muscles of left upper limb. Case-2: a 47-year-old Sri Lankan carpenter presented with subacute progressive asymmetrical painful weakness and wasting of bilateral thighs for 5 months and weight loss. Lower limb proximal muscles were wasted with reduced power and knee jerks. The nerve conduction study was normal. The electromyogram was similar to case 1 involving both quadratus femoris muscles, which was more prominent on the left side. The work up for an underlying etiology revealed only elevated fasting blood glucose and HbA1c, suggesting a new diagnosis of diabetes associated with neurological symptoms. Patient 1 was diagnosed with diabetic cervical radiculoplexus neuropathy and patient 2 with diabetic lumbosacral radiculoplexus neuropathy. Both showed significant improvement following optimization of glycemic control together with symptomatic treatment and physiotherapy.ConclusionDiagnosis of diabetic radiculoplexus neuropathy requires a comprehensive workup to rule out other sinister pathologies. This case report has a dual importance; it describes diabetic radiculoplexus neuropathy as the very first manifestation of two previously healthy people, giving rise to a new diagnosis of diabetes and, at the same time, reporting on diabetic cervical radiculoplexus neuropathy, which is extremely rare and has never been previously reported in Sri Lanka.

Assessment of Motor Unit Potentials Duration as the Biomarker of DT-DEC01 Cell Therapy Efficacy in Duchenne Muscular Dystrophy Patients up to 12 Months After Systemic–Intraosseous Administration

Duchenne muscular dystrophy (DMD) is a lethal X-linked disease caused by mutations in the dystrophin gene, leading to muscle degeneration and wasting. Electromyography (EMG) is an objective electrophysiological biomarker of muscle fiber function in muscular dystrophies. A novel, DT-DEC01 therapy, consisting of Dystrophin Expressing Chimeric (DEC) cells created by fusing allogeneic myoblasts from normal donors with autologous myoblasts from DMD-affected patients, was assessed for safety and preliminary efficacy in boys of age 6–15 years old (n = 3). Assessments included EMG testing of selected muscles of upper (deltoideus, biceps brachii) and lower (rectus femoris and gastrocnemius) extremities at the screening visit and at 3, 6, and 12 months following systemic–intraosseous administration of a single low dose of DT-DEC01 therapy (Bioethics Committee approval no. 46/2019). No immunosuppression was administered. Safety of DT-DEC01 was confirmed by the lack of therapy-related Adverse Events or Serious Adverse Events up to 22 months following DT-DEC01 administration. EMG of selected muscles of both, ambulatory and non-ambulatory patients confirmed preliminary efficacy of DT-DEC01 therapy by an increase in motor unit potentials (MUP) duration, amplitudes, and polyphasic MUPs at 12 months. This study confirmed EMG as a reliable and objective biomarker of functional assessment in DMD patients after intraosseous administration of the novel DT-DEC01 therapy.

Axial Postural Abnormalities in Parkinsonism: Gaps in Predictors, Pathophysiology, and Management.

Axial postural abnormalities are common and disabling motor complications of Parkinson's disease (PD) and parkinsonism. They consist of abnormal trunk or neck postures in the upright position, often interfering with daily life activities.1-5 A high number of patients with PD may develop one or more axial postural abnormalities, which may begin as minor forms, almost universal in persons with parkinsonism (eg, minor flexed posture of the trunk and lower limbs), and progress to severe forms such as camptocormia, antecollis, or Pisa syndrome in over 20% of patients,1 although the definitions of severe axial postural abnormalities were purely based on subjective/expert opinion. Drug-induced parkinsonism or progressive supranuclear palsy may also present axial postural abnormalities, and in multiple system atrophy these symptoms are more frequent than in PD and occur earlier in the disease course.2, 6 Because axial postural abnormalities are associated with an increased risk of falling, pain, and diminished quality of life, their proper prevention and management is warranted.2, 4, 5, 7, 8 However, to date, recommendations for multidisciplinary management and prevention remain an unmet need.3 Diagnosis is typically based on a simple clinical examination, whereas treatments (eg, pharmacological, physical therapy, and surgical treatments) have been evaluated only in small single-center studies that failed to show consistent, long-lasting improvement.2, 5, 8-10 The absence of reliable protocols for the assessment, treatment, and prevention of axial postural abnormalities in parkinsonism is probably due to the largely obscure pathophysiology and uncertainty about prognostic factors needed to estimate beneficial responses to therapy (eg, duration of axial postural abnormalities).2, 5, 8, 11-13 The aim of this viewpoint is to critically analyze the literature on axial postural abnormalities, identify the current issues and gaps, and formulate proposals for current clinical management and future research exploration. Research on clinical predictors and risk factors for the onset of axial postural abnormalities in parkinsonism was mainly limited by the low quality of the methodology in the available literature (Supporting Information).2, 5, 8 Indeed, only a few studies were aimed primarily at the analysis of risk factors, and most studies were cross-sectional, lacking adequate longitudinal follow-up. In most cases the patient sample (usually PD) was heterogeneous for disease severity and stage. Clinical predictors were investigated for all axial postural abnormalities; however, the dependent variable in many studies was the presence of more than one axial postural abnormality, rather than a singular one. This approach renders it difficult to identify clinical predictors specific for each axial postural abnormality, which may vary between camptocormia, Pisa syndrome, and antecollis. Also, the cutoffs defining an axial postural abnormality differed across studies and were not stated in many cases. This generated possible bias in the prevalence rates due to differences in the clinical characteristics of patient samples. The identification of clinical predictors in patient samples presenting different degrees of trunk/neck flexion is challenging and limits interpretation of the study results. For example, patients with greater trunk flexion may also have more motor complications (ie, motor fluctuations) that make it difficult to identify the clinical predictors for mild axial forms (ie, anterior trunk flexion),3 which are of major clinical interest for prevention strategies. Finally, the variability in tools and reference bone points used for quantifying the degree of axial postural abnormalities renders comparison of study results arduous. The pathophysiology of axial postural abnormalities in PD is not clear, but several causes have been proposed,2, 5, 8 including central mechanisms (eg, imbalance in basal ganglia functioning leading to dystonia/rigidity, altered sensory–motor integration, higher cognitive function deficits) and/or peripheral mechanisms (ie, alteration in the musculoskeletal system).2, 5, 8 The main pathophysiological mechanisms considered in the literature are discussed here (Supporting Information). Dystonia, or a more general hyperactivity of paraspinal and nonparaspinal muscles, is the most common explanation for axial disability based on findings from electromyographic investigation.2, 5, 8, 9, 14-20 The hypothesis that dystonia underlies axial postural abnormalities is supported by three main findings: (1) the existence of drug-induced Pisa syndrome or camptocormia, (2) the (rare) existence of sensory tricks to alleviate some postural abnormalities, and (3) evidence of misalignment improvement by botulinum toxin type-A or lidocaine administration in some patients.2, 5, 8 However, in patients with Pisa syndrome, electromyography findings have been inconsistent concerning the side (ipsilateral or contralateral) of hyperactivity of paraspinal and nonparaspinal muscles in relation to trunk bending and PD asymmetry.16, 18, 19 Some studies suggested two different electromyographical patterns: (1) hyperactivity of lumbar and thoracic paraspinals ipsilateral to the trunk-leaning side during quiet stance and voluntary contralateral trunk flexion18, 21 and (2) hyperactivity of nonparaspinal muscles (eg, external oblique muscles, rectus femoris, and iliopsoas) ipsilaterally to the leaning side during quite stance and during voluntary contralateral trunk flexion.17 The paraspinal muscles contralateral to the side of flexion may have a compensatory action to further limit trunk bending.17 Other studies reported tonic and persistent activity in the paraspinal thoracic muscle and/or abdominal oblique muscles ipsilateral to the bending side and less-affected PD side, along with reduced/absent activity of the same muscles on the opposite side.19 In patients with camptocormia, studies suggested that the bilateral abdominal internal and the external oblique muscles, together with the rectus abdominis muscles, may be responsible for camptocormia with thoracic fulcrum,14 whereas rectus abdominis and iliopsoas hyperactivity could be more frequently involved in camptocormia with lumbar fulcrum.14, 20 Another study found hyperactivity of paraspinal muscles (ie, iliocostalis lumborum, longissimus, and multifidus) and, to a lesser extent, the rectus femoris but not rectus abdominis.15 It is probable that some hyperactivities observed in camptocormia, like those of paraspinal muscles that are spine erectors, are compensatory. Patients with antecollis showed hypertrophy and active spasms or hyperactivity in anterior (sternocleidomastoid muscles) and posterior (semispinalis, splenius capitis, trapezius, and levator scapulae) neck muscles.2 Passive head-up maneuvers may be limited by marked bilateral contractions of sternocleidomastoid muscles.2 The paucity of studies and objective measures to identify and quantify dystonia complicates the interpretation of these findings. Needle electromyography (EMG) has limited use because it is invasive and can be challenging when applied in deep muscles. Also, interpretation of needle EMG is relatively subjective as it is technically difficult to perform and has not been standardized for investigating axial muscles, and quantitative normative measures for activation of these muscle groups are not available. Finally, when EMG is performed in those with long-standing symptoms, it remains difficult to reliably separate primary abnormalities (ie, those causing postural abnormalities) from secondary ones (ie, resulting from the chronic changes in posture, or related to compensatory mechanisms). No studies have specifically and systematically evaluated rigidity in patients with axial postural abnormalities. During clinical examination in the supine position, patients demonstrate almost complete resolution of trunk bending, whereas when sitting or standing the paravertebral muscles may appear to have a wooden consistency.2, 15 The association between axial postural abnormalities and a more severe motor impairment and a rigid-akinetic phenotype makes rigidity a process worthy of investigation, albeit difficult to measure it empirically. Patients with PD have difficulty in properly controlling their postural stabilization and orientation (and also their interaction) based on sensory information from muscles and joints.2 PD patients with Pisa syndrome or camptocormia find it more difficult to achieve good postural alignment with gravity and display greater velocity of body sway than patients without axial postural abnormalities.22, 23 Patients with camptocormia with a lower fulcrum may have more severe gait and postural control deficits than patients with a thoracic fulcrum or patients without camptocormia.23 However, no studies have so far investigated the relationship between antecollis and postural instability. Postural control is a complex system involving the integration of different sensory inputs, including vestibular, visual, and proprioceptive. Some findings support the notion that proprioceptive function/kinesthesia is abnormal in PD.22, 23 Evidence was initially restricted to motor control of the limbs,24 but more recent studies22, 23 showed that proprioceptive defects might also affect axial motor control not only in the yaw plane (turning about the vertical axis)24 but also in the sagittal and coronal planes. Further studies are needed to understand the contribution of defective proprioceptive and kinesthesia in the pathophysiology of axial postural abnormalities.2, 24 Moreover, postural control depends on vestibular information. PD patients with Pisa syndrome may present with a central, peripheral, or mixed vestibular dysfunction2 along with a deviation in the subjective visual vertical,25 which was estimated to occur in about 67% of PD patients.26 A recent case–control study found worse performance on visuospatial ability tasks by PD patients with Pisa syndrome compared to PD controls without axial postural abnormalities.27 Visuospatial deficits are associated with dysfunctional subjective visual vertical, possibly contributing to altered perception of the trunk in space and the development of Pisa syndrome but not camptocormia.27 Whether visual spatial deficits and subjective visual vertical are defective and might also contribute to the development of antecollis has not been systematically investigated yet. Moreover, postural control demands complex motor–cognitive interactions that rely on high attentional resources and conserved executive functions. Some studies reported lower scores on tasks exploring executive functions (ie, divided attention, inhibitory control, and delayed free recall in verbal learning), perceptual visuospatial functions, and language for patients with Pisa syndrome compared to patients with PD without axial postural abnormalities.2, 5, 8, 28 Nevertheless, the association between kinesthetic/proprioceptive and cognitive deficits with axial postural abnormalities remains controversial. Without further details from pathophysiology studies, and also without intervention studies, three possibilities remain: (1) these deficits are a mere association (ie, they merely coincide with those with more severe disease), (2) these dysfunctions are not causal but rather a secondary manifestation (ie, they result as a consequence of the axial postural abnormalities), or (3) they are actually a contributing factor. The bulk of evidence from EMG (eg, fibrillation potentials, small polyphasic motor unit potentials, and weakness),5, 8, 14, 15, 17, 19, 29-34 muscle biopsy (eg, abnormal histology),5, 8, 29-32, 35 and muscle imaging (eg, fatty infiltration of muscles and muscle atrophy)5, 8, 9, 14, 17, 19, 29-31, 36 suggests myopathy as a contributing factor to the development of axial postural abnormalities. The cause of myopathy remains unclear, but ongoing research marks it as a secondary myopathic process, as a consequence of a chronically maintained abnormal posture.34 These phenomena probably reflect a continuum from early myopathic changes (ie, edema and partial swelling, contrast enhancement without degenerative muscle changes) in the early stages of camptocormia to progression to muscle atrophy and fatty degeneration in the end stage as shown by muscle magnetic resonance imaging (MRI) and biopsy. Although the exact cause of these muscular changes is unclear, they may arise due to muscle disuse or denervation secondary to chronic primary trunk misalignment. Camptocormia might be a consequence of overusing paraspinal muscles due to rigidity in patients with PD or a pronounced proprioceptive dysregulation in the context of underlying disease. Although a primary myopathy has been suggested to explain Pisa syndrome,19 no pathological studies have proven this hypothesis. Therefore, the observed muscular changes are probably caused by secondary mechanisms. The atrophy of paraspinal muscles ipsilateral to the bending side may be due to muscle disuse (excluded because of hyperactivity of nonparaspinal muscles) and cannot contribute to the development of Pisa syndrome; contralateral muscle atrophy instead might be secondary to the stress of prolonged stretching, as a consequence of muscle weakness, theoretically leading to Pisa syndrome.17 The mechanical efficiency of muscular activation of trunk extension (especially at the thoracic level) was markedly reduced in PD patients with camptocormia compared to those with PD without postural issues and to healthy controls, which suggests impairment of neuromuscular recruitment.34 The EMG of the paraspinal muscles is technically difficult, but this disadvantage is relative, as MRI and muscle biopsy can show the presence of myopathy. Although the finding of a monomorphic myopathy in the camptocormia of PD patients can be considered corroborated,35 the clarification of its cause remains an important task. Currently, the recording of myopathy with its subdivision into acute and chronic forms of muscle changes provides clues for therapeutic options.12 Postural improvement after high-frequency deep brain stimulation (DBS) of the bilateral subthalamic nuclei37 supports the notion that axial postural abnormalities may result from dysfunction of the basal ganglia. There is limited evidence for the presence of drug-induced axial postural abnormalities in persons with parkinsonism,2, 5, 8 with a dose reduction (or even complete withdrawal) or switching to another dopaminergic medication leading to improvement in posture.2, 8, 38 Finally, patients with axial postural abnormalities may present with a concomitant clinical history of back surgery (eg, laminectomy), degenerative spinal conditions, or trauma, which may have mechanical effects on bones or soft tissue (eg, muscles or fascia) and predisposing to their development.39 In clinical practice, the first step is to objectively measure the degree of trunk and/or neck flexion preferably while the patient is wearing only underwear (Fig. 1) during standing and walking.40 We suggest to investigate the possible presence of mild forms of axial postural abnormalities at each visit and inform and educate patients and caregivers on these symptoms; when actual axial postural abnormalities have been identified, clinicians could consider pharmacological and nonpharmacological interventions for their treatment. Figure 2 shows a practical road map as guidance for their clinical management. Four major issues may have limited the progress of research in this field: (1) different nosology and cutoffs to define axial postural abnormalities, (2) lack of common and objective assessment procedures, (3) heterogeneity of study design, and (4) heterogeneity of patient samples. Future research should focus on their clinical evaluation in terms of early detection and quantification using consensus-based criteria.3 Prospective, observational, long-term studies with large samples are immediately needed to explore the potential risk (causal) factors and pathophysiology involved in their development. From a therapeutic point of view, we call for well-controlled clinical trials: randomized trials using standard criteria for inclusion and endpoint measurement3 are needed to compare the efficacy of different pharmacological and nonpharmacological interventions and their combined effect (ie, botulinum toxin injections + physiotherapy). Such controlled studies could also focus on the merits of dopaminergic therapy withdrawal when these are suspected to have played a role in causing axial postural abnormalities. Moreover, we suggest researchers focus on a single postural abnormality per study, because risk factors, pathophysiology, and response to treatments may vary between camptocormia, Pisa syndrome, and antecollis. Finally, prevention programs using common diagnostic criteria3 should be investigated to study how the development of axial postural abnormalities can be avoided. Educate patients and their families to monitor possible improvement or worsening of posture. Adjustment of pharmacological therapy: remove the prescribed dopaminergic therapy potentially associated with the subacute onset of axial postural abnormality. The removal of therapy needs to be done very cautiously as this may also lead to a worsening of the underlying parkinsonism.8 Other expert opinion–based options include the following: botulinum toxin injection of hyperactive muscles should be cautiously considered for each patient based on EMG findings, in carefully selected patients, under the care of experts; avoiding injections of compensatory paraspinal and nonparaspinal muscles; prompt physiotherapy intervention to strengthen weak/compensatory trunk/neck muscles and improve balance and mobility; and prescription of walking aids (ie, high-frame walker) if needed. When a patient is suitable for DBS aimed at managing motor symptoms, camptocormia, and Pisa syndrome could also improve after surgery. Orthopedic surgery should be considered in very selected cases: patients should be properly counseled regarding the increased risk of operative complications and closely followed for incipient failure. We thank Rossella Targa (librarian) for her assistance in developing the literature search strategy. Open Access Funding provided by Universita degli Studi di Verona within the CRUI-CARE Agreement. (1) Writing of the first draft: C.G., M.T., C.A.A. (2) Data collection: C.G., C.A.A., J.N., C.A., D.G., M.L.D., D.S., Y.L., M.A.-W., M.S., R.W., V.T.L., G.I., and SC. (3) Review and critique: all authors. R.B. receives salary from Chulalongkorn University and stipend from the Royal Society of Thailand, has received consultancy and/or honoraria/lecture fees from Abbott, Boehringer-Ingelheim, Britannia, Ipsen, Novartis, Teva-Lundbeck, Takeda, and Otsuka pharmaceuticals; he has received research funding from the Newton Fund, the UK Government, Thailand Science and Research Innovation Bureau, Thailand Research Fund, Crown Property Bureau, Chulalongkorn University, and the National Science and Technology Development Agency; he holds patents for laser-guided walking stick, portable tremor device, nocturnal monitoring, and electronic Parkinson's disease symptom diary as well as copyright on Parkinson's mascot, dopamine lyrics and teaching video clips for common nocturnal and gastrointestinal symptoms for Parkinson's disease. A.F. reports the following: Consultancies from Abbvie, Medtronic, Boston Scientific, Sunovion, Ipsen, Merz; Advisory Boards of Abbvie, Boston Scientific, Ceregate, Inbrain, Ipsen, Medtronic, Jazz, Biogen/Sage; Honoraria from Abbvie, Medtronic, Boston Scientific, Sunovion, UCB, Ipsen; grants from University of Toronto, Weston foundation, Abbvie, Medtronic, Boston Scientific, Michael J Fox Foundation, European Union, MSA coalition, Dystonia Medical Research Foundation. L.L. reports the following: Consultancies and Honoraria from Bial, Zambon, Abbvie and Grants from University of Turin, Zambon, Abbvie. N.M. reports the following: dvisory Boards for Angelini, GW Pharmaceuticals and Grants from UCB Pharma, Desitin, Eisai, LivaNova, Angelini, GW Pharmaceuticals. M.M. reports the following: Consultant: St Jude/ Abbott, Honoraria: Glaxo Research grants: Glaxo, Allergan, TEVA. Royalties: Springer, Random House, Cambridge University press, Humana Press. Editor honorarium Wiley & Son. Movement Disorders Society.receives salary from Chulalongkorn University and stipend from the Royal Society of Thailand, has received consultancy and/or honoraria/lecture fees from Abbott, Boehringer-Ingelheim, Britannia, Ipsen, Novartis, Teva-Lundbeck, Takeda, and Otsuka pharmaceuticals; he has received research funding from the Newton Fund, the UK Government, Thailand Science and Research Innovation Bureau, Thailand Research Fund, Crown Property Bureau, Chulalongkorn University, and the National Science and Technology Development Agency; he holds patents for laser-guided walking stick, portable tremor device, nocturnal monitoring, and electronic Parkinson's disease symptom diary as well as copyright on Parkinson's mascot, dopamine lyrics and teaching video clips for common nocturnal and gastrointestinal symptoms for Parkinson's disease. A.F. reports the following: Consultancies from Abbvie, Medtronic, Boston Scientific, Sunovion, Ipsen, Merz; Advisory Boards of Abbvie, Boston Scientific, Ceregate, Inbrain, Ipsen, Medtronic, Jazz, Biogen/Sage; Honoraria from Abbvie, Medtronic, Boston Scientific, Sunovion, UCB, Ipsen; grants from University of Toronto, Weston foundation, Abbvie, Medtronic, Boston Scientific, Michael J Fox Foundation, European Union, MSA coalition, Dystonia Medical Research Foundation. L.L. reports the following: Consultancies and Honoraria from Bial, Zambon, Abbvie and Grants from University of Turin, Zambon, Abbvie. N.M. reports the following: dvisory Boards for Angelini, GW Pharmaceuticals and Grants from UCB Pharma, Desitin, Eisai, LivaNova, Angelini, GW Pharmaceuticals. M.M. reports the following: Consultant: St Jude/ Abbott, Honoraria: Glaxo Research grants: Glaxo, Allergan, TEVA. Royalties: Springer, Random House, Cambridge University press, Humana Press. Editor honorarium Wiley & Son. Movement Disorders Society. Data sharing not applicable to this article as no datasets were generated or analysed during the current study Data S1. Supporting Information Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Chemotherapy induced juvenile dermatomyositis: a novel presentation- a case report

BackgroundIdiopathic connective tissue disease juvenile dermatomyositis (JDM) is characterised by inflammatory myositis and distinctive skin abnormalities. Only a few cases of Dermatomyositis (DM) owing to chemotherapy used to treat cancer have been reported, despite the fact that the link between DM and cancer in adults is widely known. We describe the case of a female, age 14, who experienced DM as a side effect of chemotherapy following enucleation for retinoblastoma. We also discussed our patient's likely pathophysiology of JDM after treatment.Case presentationA 14-year-old female came to our facility complaining of trouble walking and bluish-black discoloration on her neck, elbows, forehead, and knees that had been present for eight months. The patient had undergone enucleation of the left eye due to retinoblastoma, followed by 40 cycles of radiation therapy and 13 cycles of chemotherapy with Cyclophosphamide, Etoposide, Carboplatin, Vincristine, and Dactinomycin. Her serum LDH and CPK levels were high, and she tested positive for ANA. The muscle biopsy was consistent with the changes of DM. When electromyography was performed, it revealed tiny, fibrillating, polyphasic motor unit potentials and sharp, positive waves that were suggestive with DM. A diagnosis of JDM was made after taking into account the symptoms, biochemical data, muscle biopsy, and electromyography results. The patient's symptoms started to get better once methotrexate and oral corticosteroids were started.ConclusionThis case report emphasises the value of ongoing observation after cancer chemotherapy because specific cutaneous and muscle symptoms may lead paediatricians to consider the possibility of chemotherapy-induced JDM, which is uncommon in young patients.

Needle Electromyography in the Acute Phase of Stroke: Correlation With Severity and Muscle Strength: Preliminary Findings.

After the stroke, the development of the second motor neuron degeneration can reduce muscle strength and functional capacity. The aim of this study was to describe the electro-myographic findings in the acute phase of stroke and to correlate them with the severity and muscle strength. Twenty patients were studied in the first 72 hours after stroke. The severity of the lesion was assessed using the National Institutes of Health Stroke Scale (NIHSS), and muscle strength was assessed using the Medical Research Council Scale (MRC). Sensory conduction and motor conduction were studied to exclude peripheral polyneuropathy, radiculopathies, or other neuro-muscular diseases, and electro-myography (EMG) was performed with co-axial needle electrodes in the deltoid, carpal radial extensor, vastus lateralis, and anterior tibialis at rest, slight effort and maximum effort. The associations between qualitative and quantitative variables were studied using the Chi-square test and Fisher's exact test. Among the patients, 40% had abnormal EMG [positive sharp waves (PSWs), fibrillation, fasciculations, and abnormal patterns in maximum effort]. Positive correlations were found between NIHSS and PSW (p = 0.005; r = 0.65) and abnormal EMG (p = 0.017; r = 0.72), and negative correlations were found between MRC and PSW (p = 0.041; r = -0.83) and abnormal EMG (p = 0.027; r = -0.81). It was concluded that the main EMG findings in the acute phase of stroke were the presence of the denervation process and polyphasic motor unit potentials. These changes in EMG were correlated with stroke severity and lower muscle strength.

A novel variant in the COL6A1 gene causing Ullrich congenital muscular dystrophy in a consanguineous family: a case report

BackgroundCollagen VI-related dystrophies are a subtype of congenital muscular dystrophy caused by pathogenic variants in COL6A1, COL6A2 or COL6A3 genes affecting skeletal muscles and connective tissue. The clinical phenotype ranges from the milder Bethlem myopathy to the severe Ullrich congenital muscular dystrophy (UCMD). Herein, we report the first consanguineous Sri Lankan family with two children affected with UCMD due to a novel variant in the COL6A1 gene.Case presentationTwo sisters, aged 10-years and 7-years, presented with progressive, bilateral proximal muscle weakness. Both probands had delayed motor milestones and demonstrated difficulty in standing from a squatting position, climbing stairs and raising arms above the shoulders. Cognitive, language and social development were age appropriate. Examination showed proximal muscle weakness of the upper and lower extremities and hyperlaxity of the wrist and fingers in both with some variability in clinical severity noted between the two siblings. Serum creatine kinase levels were elevated, and electromyography showed low polyphasic motor unit potentials in the 10-year-old and myopathic features with short duration motor unit potentials with no polyphasia in the 7-year-old. Whole exome sequencing (WES) was performed and a novel, homozygous missense, likely pathogenic variant in exon 25 of COL6A1 gene [NM_001848: c.1667G > T;NP_001839.2:p.Gly556Val] was identified in both probands. This variant was validated by Sanger sequencing in proband 1 as well as proband 2, and the parents and an unaffected sibling were found to be heterozygote carriers for the same variant.ConclusionsThe findings in this family add to the expanding number of COL6A1 variants identified and provides a better understanding of the genotype-phenotype correlations associated with UCMD.

Sporadic distant neurotoxin effects in the chronic treatment of spasticity

Neurotoxin therapy is an effective component of comprehensive spasticity management. The two cases presented demonstrate adverse effects. Patient S is a 60-year-old female with right spastic hemiparesis due to left hemispheric stroke (age 46) treated with therapy, bracing, oral baclofen. Patient R is a 28-year-old female with left spastic hemiparesis due to hemispherectomy (age 6). For patient S, onabotulinumtoxinA (ONA) was initiated at 300 units (u) to the right upper extremity (RUE), advanced to 500u. She received injections every 3–3.5 months for over 9 years and continued to function independently. At routine follow-up, she related left upper extremity (LUE) weakness that she noted but did not report with her two prior injections. She denied any other symptoms. Examination revealed mild, diffuse LUE weakness, imaging was unremarkable and EMG demonstrated a chronic LUE axonal polyradiculopathy. ONA was continued at 300u to the RUE with somewhat lesser but maintained benefit without adverse effects. For patient R, ONA was initiated at 400u to the LUE every three months for 13 rounds, advanced to 500u. Contralateral (RUE) weakness developed after the second round of 500u dosing. Diagnostic evaluation was notable only for increased insertional activity, fibrillation potentials and decreased recruitment with subsequent long duration polyphasic motor unit potentials. Unchanged with high dose steroids, weakness improved with IVIG. Repeat ONA with 500u resulted in good local effect, recurrent contralateral upper and lower extremity weakness. EMG demonstrated contralateral cervical, thoracic and lumbosacral axonal polyradiculopathy. Symptoms improved with IVIG. Patient declined subsequent ONA. Both patients were treated with neurotoxin therapy for 3–9 years with good clinical response before developing the adverse reaction. Weakness distant to the injection sites is supported by electrodiagnostic findings of contralateral axonal polyradiculopathy. The clinical presentations suggest the possibility that the adverse effect of distant weakness may be immune-mediated and dose-related.

Lateral Leg Pain in an Avid Hiker After a Fall

HISTORY: A 62-year-old female with a history of hip OA and low back discomfort presents with left lateral leg pain that started after a fall onto her back 11 months ago. Pain is described as a constant throbbing in the left lateral calf, ankle, and dorsal foot. Pain worsens with ambulation and is relieved by rest. Noninvasive vascular studies ruled out claudication. Prior treatments included left L5 nerve root block, lumbar ESI, SI joint injection, chiropractic treatment, pain medications, and therapy with limited success. She presents to our sports medicine clinic for a diagnostic ultrasound of the left lateral leg region. PHYSICAL EXAMINATION: Guarded gait favoring weight bearing on right lower extremity. Mild tenderness over the proximal tibiofibular joint. No focal area of tenderness noted at lateral knee joint line or distal iliotibial band. Range of motion about the knee and ankle were both full without pain and strength was intact. Allodynia noted to light touch over left anterolateral leg, ankle, and dorsal foot. Straight leg raise and lumbar facet challenge were negative. Lumbar Spurling’s was positive on the left. DIFFERENTIAL DIAGNOSIS: 1. Superficial peroneal neuropathy 2. Common peroneal neuropathy 3. Lumbar radiculopathy TEST AND RESULTS: -MRI lumbar spine: Mild multilevel DJD without significant stenosis. -MRI left tibia-fibula: Subtle edema in the peroneal muscle area. Diffuse symmetric atrophy in both muscles. -EMG/NCV: Decreased amplitude in left superficial peroneal response (4 mV vs 12 mV on contralateral side) and mildly prolonged peak latency. No signs of lumbar radiculopathy. -Left lateral leg/knee ultrasound: Swollen superficial peroneal nerve at the site of penetration through peroneus longus muscular fascia (0.08 cm proximally and 0.22 cm distally). FINAL WORKING DIAGNOSIS: Left superficial peroneal neuropathy TREATMENT AND OUTCOMES: 1. Sonographically guided superficial peroneal nerve hydrodissection (HD) x 2 resulted in improvement in painless walking distance and decrease in pain scale by 50-60%. 2. Repeat elective EMG/NCV 2 months later demonstrated signs of re-innervation of the left superficial peroneal nerve evidenced by normalized and symmetric sensory response amplitude (8 mV) and peak latency measures with polyphasic motor unit potentials seen in the fibularis longus.

Consensus statement: Using laryngeal electromyography for the diagnosis and treatment of vocal cord paralysis.

The purpose of this study was to develop an evidence-based consensus statement regarding use of laryngeal electromyography (LEMG) for diagnosis and treatment of vocal fold paralysis after recurrent laryngeal neuropathy (RLN). Two questions regarding LEMG were analyzed: (1) Does LEMG predict recovery in patients with acute unilateral or bilateral vocal fold paralysis? (2) Do LEMG findings change clinical management in these individuals? A systematic review was performed using American Academy of Neurology criteria for rating of diagnostic accuracy. Active voluntary motor unit potential recruitment and presence of polyphasic motor unit potentials within the first 6 months after lesion onset predicted recovery. Positive sharp waves and/or fibrillation potentials did not predict outcome. The presence of electrical synkinesis may decrease the likelihood of recovery, based on 1 published study. LEMG altered clinical management by changing the initial diagnosis from RLN in 48% of cases. Cricoarytenoid fixation and superior laryngeal neuropathy were the most common other diagnoses observed. If prognostic information is required in a patient with vocal fold paralysis that is more than 4 weeks and less than 6 months in duration, then LEMG should be performed. LEMG may be performed to clarify treatment decisions for vocal fold immobility that is presumed to be caused by RLN. Muscle Nerve 53: 850-855, 2016.

Diagnostic Yield of Electromyography in Children With Myopathic Disorders

BackgroundInterpretation of pediatric electromyography interpretation in myopathic disorders is technically challenging. We assessed our electromyographic experience with respect to sensitivity and specificity in pediatric myopathy. MethodsWe did a retrospective chart review of patients ≤18 years between 2009 and 2013. Two hundred twenty-four electromyographic studies were reviewed with the following referral diagnoses: myopathy, muscle weakness, neuromuscular disorders, myositis, myalgia, myoglobinuria, myasthenia, myotonia, cramps, periodic paralysis, hypotonia, and developmental delay. Only children who had an electromyography and muscle biopsy were included for analysis. Patients with neurogenic electromyography and neuromuscular junction disorders were excluded. Myopathic electromyography was defined as short duration, low amplitude, polyphasic motor unit potentials with rapid recruitment. ResultsSeventy-two patients were included (age range, 6 months-18 years). The following observations were made: group A: myopathic electromyography or pathognomonic of muscle disease and biopsy or genetically confirmed myopathy (32 cases); group B: myopathic electromyography but biopsy normal or nondiagnostic (12 cases); group C: normal electromyography but biopsy or genetically confirmed myopathy (three cases, all with metabolic myopathy); and group D: electromyography normal and biopsy normal or nondiagnostic (25 cases). The most common diagnoses were congenital myopathy (seven cases), metabolic myopathy (six cases), muscular dystrophy (six cases), genetically confirmed myopathy (five cases), myopathy, undefined (five cases), and inflammatory myopathy (four cases). ConclusionsPediatric electromyography was 91% sensitive and 67% specific in myopathic disorders. The metabolic myopathies were commonly missed by electromyography.

Segmental architecture of the spinal accessory nerve

Nicolas de Tribolet, MD Editor-in-Chief Acta Neurochirurgica The spinal accessory nerve has become a workhorse for brachial plexus reconstruction following traumatic peripheral nerve injury. It is frequently used as an extraplexal motor donor for transfer to injured nerves, including the suprascapular nerve, musculocutaneous nerve, and others [1, 10]. The spinal accessory nerve’s large motor fiber content [3] and infrequent injury from brachial plexus trauma [2] has yielded a high success rate for these transfers [9, 11]. The concept of nerve transfers for peripheral nerve injuries has been extended to apply to spinal cord injury patients [4]— transferring supralesional nerves into infralesional nerves to enable cortical control of the targeted muscle. A 36-year-old man presented to our clinic for consideration of reconstructive surgery for a high cervical cord injury from a surfing accident 14 years previously. His injury consisted of cervical fractures from C1 through C6, with burst fracture and dislocation of C4 and C5. His current lowest level of function was C4 (ASIA impairment scale A); his motor exam consisted of full strength shoulder shrug bilaterally, but without motor control of any muscle of the left upper extremity. On the right he had weak 4/5 (MRC scale) shoulder abduction and 2/5 external rotation, 3/5 pectoralis major muscle, 4/5 elbow flexion, and trace flexor carpi radialis contraction. Our goals were to identify transferable nerves to achieve elbow flexion on the left; the only donor source would be the spinal accessory nerve. Needle EMG was performed to assess for evidence of denervation of the trapezius muscle that would indicate fewer healthy axons for transfer. Very mild chronic denervation was observed in the middle trapezius, whereas there was moderate chronic denervation in the lower trapezius, including polyphasic potentials, rapid firing, and large motor unit potentials (Fig. 1). The pattern of denervation suggested correlation with his spinal cord injury: an MRI demonstrated near-total loss of spinal cord parenchyma from mid-cervical three to rostral cervical six vertebral bodies which form the C4 through C6 nerves. A segmental pattern of innervation of the trapezius muscle has not been previously defined. Several animal models have shown consistent innervation of the trapezius muscle by the C1–C7 spinal cord segments [5], with the predominant innervation deriving from C2–C6 [6, 8, 12]. The bilateral EMG findings suggest to us that the trapezius muscle is segmentally innervated, with rostral muscle coordinated by rostral cervical spinal segments and caudal muscle coordinated by caudal cervical spinal segments. The salient message, along with the previously undetected pattern of innervation, is that the concepts of nerve transfers for brachial plexus injury cannot be uniformly applied to nerve transfers for spinal cord injury. Although the spinal accessory nerve is a cranial nerve by its dural exit, it is a spinal nerve by origin of its motor neuron pool [7]. This segmental architecture is susceptible to high cervical spine injury, reducing the ability of the spinal accessory nerve to serve as a source for transfer of healthy motor neurons. Preoperative electrodiagnostic evaluation of the quality of the innervation of the trapezius muscle is essential for consideration of the M. A. Mahan (*) Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, 350 W. Thomas Road, Phoenix, AZ 85013, USA e-mail: Neuropub@dignityhealth.org

Acetabular paralabral cyst as a rare cause of obturator neuropathy: a case report.

An acetabular paralabral cyst is a benign soft tissue cyst usually seen in association with a tear of the acetabular labrum. Acetabular paralabral cysts are often the cause of joint pain, but they rarely cause compression of the adjacent neurovascular structures. We present a case of a 63-year-old male patient who had paresis and atrophy of right hip adductor muscles. Right obturator neuropathy was confirmed through an electrodiagnostic study. In addition, magnetic resonance imaging showed a paralabral cyst in the right acetabulum which extended to the pelvic wall. The patient underwent conservative treatment without surgical procedure. The pain was decreased after 1 month of conservative therapy. The pain was decreased at the 1-month follow-up. Follow-up electromyography showed polyphasic motor unit potentials in adductor magnus and adductor longus muscles. Based on the experience of this case, an acetabular paralabral cyst should be considered as one of the rare causes of obturator neuropathy.

WS2-1. A case of slowly progressive muscular atrophy in post hematopoietic stem cell transplantation: Electrophysiological and pathological findings in musculoskeletal chronic graft-versus-host disease (cGVHD)

A 38-year-old man who received bone marrow transplantation four years ago for acute lymphocytic leukemia. He felt muscle cramps and became a bed-bound state because of progressing polyarthralgia in the following year. Marked muscle atrophies, mild weakness, joint contractures, and sclerotic skin changes were noted. Motor conduction studies revealed reduction in the amplitude (2.4 mV), in the conduction velocity (41 m/s), and in the duration (11 ms) of compound muscle action potentials in the right median nerve. In concentric needle electromyography, low amplitude polyphasic motor unit potentials discharged with rapid frequency without spontaneous discharges. Mean muscle fiber CV elicited by monopolar needle electrodes were slow compared with normal control. The electrodiagnosis was myopathic change which consists of cluster of atrophic fibers, discriminated from myositis and motor neuron disease. Muscle specimen from autopsy revealed marked atrophied muscle fibers less than 10 μm in diameter. There were no necrotic and inflammatory processes. In the fascia, small numbers of infiltrating CD8 positive T lymphocytes with proliferation of collagen fibers were seen, compatible with fasciitis. There were few reports about electrophysiological and pathological findings of fasciitis in cGVHD, which must be focused on the future as distinct from the myositis.

Changes in Electromyographic Results of Patients With Lumbar Radiculopathy: A Follow-Up Study

ObjectiveTo assess the neurophysiologic changes in a group of patients with lumbar radiculopathy 5 to 12 months after their first electromyographic examination. DesignA prospective group of patients with a case definition of lumbar radiculopathy was reassessed between 5 and 12 months after their first clinical, functional, imaging, and neurophysiologic evaluation. Both the lumbar paraspinals (in which the mini-mapping technique was used) and the same lower limb muscles were explored in every patient. Relevant abnormalities were (1) positive sharp waves/fibrillation potentials, (2) polyphasic motor unit potentials, and (3) large-amplitude/long-duration motor unit potentials. Patients were sorted into 5 groups based on the type and distribution of neurophysiologic abnormalities: from 0 (no abnormalities) to 4 (denervation signs in 2 lower limb muscles and paraspinals). Patients' subjective perception of any improvement or worsening of their condition was also recorded. SettingA referral center for neurophysiologic evaluation. ParticipantsA consecutive sample of patients (N=91) with a clinical definition of lumbar radiculopathy (lumbar pain radiating down the leg and below the knee) referred for neurophysiologic assessment was selected for an initial clinical, functional, and neurophysiologic evaluation. Patients were called for a second evaluation (between 5 and 12mo). Thirty-eight (42% of the initial sample) were willing/eligible for the second evaluation. InterventionsNot applicable. Main Outcome MeasuresChanges in (1) electromyographic results; (2) patients' subjective perception of pain; and (3) quality of life, based on the Roland-Morris Questionnaire and Medical Outcomes Study 36-Item Short-Form Health Survey scores. ResultsParaspinal muscles were most frequently affected. Neurophysiologic abnormalities had improved on reassessment. Clinical improvement was more significant for those patients with initially abnormal electromyographic results. ConclusionsThere was clinical as well as electromyographic improvement in patients with lumbar radiculopathy within the first year of the initial diagnosis.

A case of polymyositis associated with Hashimoto's thyroiditis

To the Editor, Autoimmune diseases encompass a wide spectrum of disorders from organ specific to multisystemic involvement. Sometimes, autoimmune diseases coexist with each other and the overlap syndrome is defined by the development of clinical features of two or more autoimmune diseases simultaneously. There are a number of mechanisms implicated in the pathogenesis of these overlaps. Genetic factors, such as shared susceptible alleles, cross-reactivity of autoantibody, autoreactive T cell and cytokine imbalance have been suggested [1]. Hashimoto's thyroiditis is an organ specific autoimmune disorder. Its association with systemic autoimmune diseases has been described, including systemic lupus erythematosus, Sjogren syndrome, systemic sclerosis, and rheumatoid arthritis [2]. However, the occurrence of Hashimoto's thyroiditis and polymyositis is very rare and not well documented. We describe a 20-year-old woman with polymyositis who was diagnosed as Hashimoto's thyroiditis concomitantly. A 20-year-old woman was admitted to the hospital complaining of fever and pain with weakness in arms and thighs. Three months ago, she felt pain in the both extremities and had difficulty in standing, walking on stairs and rising arms over the head. At admission, blood pressure was 100/60 mmHg, heart rate was 110 beats per minute, and temperature was 39℃. Thyroid gland was diffusely enlarged with a smooth surface and soft consistency. Musculoskeletal examination revealed tenderness in all four extremities. Muscle strength of the extremities was 3 to 4/5 in arms and 3/5 in legs. On neurological examination, sensation, and deep tendon reflexes were normal or intact. Laboratory findings were as follows: white blood cell 23,180/mm3, hemoglobin 9.1 g/dL, platelet 511,000/mm3, erythrocyte sedimentation rate 58 mm/hr, C-reactive protein 10.4 mg/dL, serum total protein 8.5 g/dL, albumin 4.4 g/dL, aspartate transaminase (AST) 55 IU/L, creatinine 0.82 mg/dL, lactate dehydrogenase 1,296 IU/L (normal range, 218 to 472), creatine phosphokinase (CPK) 386 IU/L (normal range, 30 to 334), and aldolase 7.6 U/mL (normal range, 2 to 8). Thyroid stimulating hormone was 2.39 µU/mL (normal range, 0.35 to 5.50), free T4 1.03 ng/dL (normal range, 0.89 to 1.80), antithyroglobulin 732 IU/mL (normal range, 0 to 40), antimicrosomal antibody 245 IU/mL (normal range, 0 to 25), and thyroid stimulating immunoglobulin was 5% (normal range, 0 to 15). Immunological examination revealed the following: antinuclear antibody positive at 1 : 40 in speckled pattern, rheumatoid factor, anti-SSA, anti-SSB, anti-dsDNA antibody, anti-Scl-70 antibody, antiribonuclear protein and anti-Jo-1 antibody were all negative. Ultrasonogram of the thyroid gland demonstrated diffuse enlargement of the thyroid gland and 1 cm sized hypovascular echogenic nodule on right upper pole. An electromyography (EMG) finding was occasional small fasciculations and polyphasic motor unit potentials of low amplitude and short duration, suggestive of myopathy. Histological examination of the resected thyroid right lobe revealed follicular cell proliferative lesions in background of parenchymal extensive mononuclear inflammatory cell infiltration and oxyphilic changes of follicular epithelium, consistent with nodular hyperplasia in Hashimoto's thyroiditis (Fig. 1). Muscle biopsy specimen from the quadriceps showed necrotic and regenerating various sized muscle fiber and phagocytosis with endomyseal inflammatory cell infiltration and the perivascular infiltration of mononuclear cells, consistent with polymyositis (Fig. 2). She was diagnosed as having polymyositis and Hashimoto's thyroiditis and was treated with prednisolone (50 mg/day) and methotrexate (10 mg/wk). Her symptoms remarkably improved after treatment. Fever and myalgia disappeared quickly and muscle strength improved gradually. Figure 1 Microscopic finding of thyroid gland showing extensive mononuclear inflammatory cell infiltration of the parenchyma and oxyphilic changes of follicular epithelium with follicular cell proliferative lesions (H&E, × 100). Figure 2 Muscle biopsy specimen reveals interstitial mononuclear cell infiltration. Both regenerating and degenerating muscle fibers are scattered (H&E, × 200). This case showed some difficulties of interpreting laboratory data. Although, the levels of certain muscle enzyme (AST and CPK) were not so high at initial evaluation. The diagnosis of polymyositis was made by clinical, histological, and EMG findings. The conceivable explanation of these laboratory ambiguities lies in the use of corticosteroid for several weeks before the test. Although the pathogenesis and the nature of the relationship between thyroid autoimmunity and autoimmune diseases is not completely established, some hypotheses may be implicated: 1) immune modulatory effects of antithyroid antibodies; 2) molecular mimicry between thyroid and disease specific epitopes; and 3) genetic link between antithyroid autoimmunity and the susceptibility to autoimmune disease [2]. Cross-reactivity of antithyroid antibodies or autoreactive T cells with other organs and cytokine imbalance may also implicated [2,3]. About 2% of inflammatory myopathy patients exerted thyroid autoimmunity. Suppressor T cell dysfunction and lymphocyte mediated cytotoxicity have been described in patient with polymyositis and there are some evidences of suppressor T cell dysfunction in autoimmune thyroiditis [2,4]. It could be hypothesized that coexisting autoimmune thyroiditis and inflammatory myopathy develop from the common autoimmune pathogenic mechanism. In conclusion, systemic and thyroid autoimmune diseases may overlap with each other. It is important to be aware that polymyositis and autoimmune thyroiditis can coexist and a thorough evaluation of both conditions may be necessary in patients presenting with myalgia or muscle weakness.

Contralateral weakness following botulinum toxin for poststroke spasticity

We describe 2 patients who received botulinum toxin A (BoNT) for poststroke spasticity and developed contralateral limb weakness. Both patients received high doses of BoNT with large dilution volumes and injection in the proximal upper extremity muscles, and developed weakness of the contralateral upper limb. These patients then underwent electrodiagnostic testing of the affected limb. Repetitive nerve stimulation of the axillary and spinal accessory nerves revealed decrements of 23% and 16%, respectively. EMG revealed abnormal spontaneous activity and small polyphasic motor unit potentials with reduced recruitment. These findings indicated blockade of the neuromuscular junction. Both patients improved. Isolated weakness of the contralateral limb after BoNT injection for poststroke spasticity suggests diffusion of toxin through tissue planes from proximal upper extremity muscles, across the midline, to contralateral muscles. High doses of botulinum toxin, high dilution volumes, and injection of proximal upper extremity muscles appear to be risk factors for this adverse effect.

Needle electromyography at 1 month predicts paralysis of elbow flexion at 3 months in obstetric brachial plexus lesions

Treatment decisions in obstetric brachial plexus lesions are often based on clinical paralysis of elbow flexion at 3 months of age, when electromyography (EMG) is misleading because motor unit potentials (MUPs) occur in clinically paralytic muscles. We investigated whether EMG at 1 week or 1 month identifies infants with flexion paralysis at 3 months, allowing early referral. Forty-eight infants (27 females, 21 males) were prospectively studied. The presence or absence of flexion paralysis at around 1 week (median 9 d; range 5-17d), 1 month (median 31 d; range 24-53 d), and 3 months of age (median 87 d; range 77-106 d) was noted for clinical (shoulder external rotation, elbow flexion, extension, and supination) and EMG parameters (denervation activity, MUPs and polyphasic MUPs in the deltoid, biceps, and triceps muscles). At 1 month, the absence of biceps MUPs had a sensitivity of 95% for later flexion paralysis, and absence of deltoid MUPs had a sensitivity of 100% for flexion paralysis; the false-positive rates for the same findings were 21% and 33% respectively. EMG at 3 months was highly misleading as MUPs were seen in 19 of 20 clinically paralytic biceps muscles. EMG at 1 month can identify severe cases of flexion paralysis for early referral EMG of the biceps at 3 months is highly misleading; the discrepancy between the EMG and clinical testing may be due to abnormal axonal branching and aberrant central motor control.

Focal pseudohypertrophy of the left hemi-tongue

A 72 year-old man with a history of diabetes mellitus noticed that his tongue deviated to the left when it was stuck out. He consulted our hospital since this feature persisted for 9 months. The diabetes mellitus was well controlled by voglibose (0.6 mg/day) and gliclazide (80 mg/day), and serum levels of glucose and glycated hemoglobin were 104 mg/dl and 6.1%, respectively. The patient had no signs of neurologic involvement attributable to diabetes mellitus. The left side of the tongue was hypertrophic and the tongue deviated to left (Fig. 1). Left hemi-tongue weakness was evident. There was no fasciculation, and deep tendon reflexes were normal, with no pathological reflexes. The results of other neurological examinations including swallowing, speaking and tasting were negative. Electromyography of the left side of the tongue showed neuropathic motor unit action potentials, polyphasic motor unit potentials, positive sharp wave and fibrillation potentials. The number of motor units per second was decreased. The right side of the tongue showed none of these findings. All other muscles examined (deltoid, biceps, triceps, adductor of thumb, quadriceps, gastrocnemius, and tibialis anterior) showed no evidence of neuropathic or myopathic motor unit action potentials. Magnetic resonance imaging (MRI) of the tongue revealed markedly increased signal intensity in the left side of the tongue on T1-weighted images (Fig. 1a, c) and T2weighted images (Fig. 1b). The left side of the tongue was enlarged. Contrast-enhanced, T1-weighted MRI images obtained with the use of a bolus of gadoliniumdiethylenetriamine pentaacetic acid showed a circular lesion with ringed enhancement in the root of the left side of the tongue (Fig. 1d, white arrow). Intracranial abnormal signals including the brainstem were not evident on MRI. Anti-IL2 receptor antibody (303 U/ml), antinuclear antibody, and M-protein on immunoelectrophoresis were negative. Hypertrophy of the root of the left side of the tongue was evident on laryngoscopy. A biopsy of the root of the tongue showed lymphocyte infiltration with no malignant cells. Monoclonality was absent on immunohistochemical studies. One year later, short inversion time inversion recovery (STIR) images on repeated MRI showed the decreased signal intensity in the left hemitongue with increased signal intensity on T1-weighted images and T2-weighted images. The size of the circular lesion with ringed enhancement was unchanged. On the basis of the ringed enhancement on MRI and the presence of lymphocyte infiltration with no malignancy on histopathological examination, the lesion was diagnosed to be an inflammatory cystic lesion ‘‘abscess’’. On 20 months after consultation to our hospital, the left hemi-tongue weakness was static. These findings could be explained by denervation and reinnervation or by increasing frequencies of motor unit firing from the left hypoglossal nerve and adjacent motor fibers, which were impaired by the cystic lesion in the left side of the tongue. Neuralgic muscle hypertrophy of the limbs has been reported in several types of lower motor neuron disease, such as multifocal motor neuropathy [1], Guillain-Barre syndrome [1], and radiculopathy [3, 4], but such hypertrophy involving cranial nerves has not been reported previously to our knowledge. Prior studies suggest that continuous, spontaneous electrical activity of a muscle associated with disease conditions can cause neuralgic H. Kataoka (&) S. Ueno Department of Neurology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan e-mail: hk55@naramed-u.ac.jp

Anal sphincteric neurogenic injury in asymptomatic nulliparous women and fecal incontinence

While anal sphincter neurogenic injury documented by needle electromyography (EMG) has been implicated to cause fecal incontinence (FI), most studies have been uncontrolled. Normal values and the effects of age on anal sphincter motor unit potentials (MUP) are ill defined. The functional significance of anal sphincter neurogenic injury in FI is unclear. Anal pressures and EMG were assessed in 20 asymptomatic nulliparous women (age, 38 ± 5 yr; mean ± SE) and 20 women with FI (54 ± 3 yr). A computerized program quantified MUP duration and phases. These parameters and MUP recruitment were also semiquantitatively assessed by experienced electromyographers in real time. Increasing age was associated with longer and more polyphasic MUP in nulliparous women by quantitative analysis. A higher proportion of FI patients had prolonged (1 control, 7 patients, P = 0.04) and polyphasic MUP (2 controls, 9 patients, P = 0.03) at rest but not during squeeze. Semiquantitative analyses identified neurogenic or muscle injury in the anal sphincter (11 patients) and other lumbosacral muscles (4 patients). There was substantial agreement between quantitative and semiquantitative analyses (κ statistic 0.63 ± 95% CI: 0.32-0.96). Anal resting and squeeze pressures were lower (P ≤ 0.01) in FI than controls. Anal sphincter neurogenic or muscle injury assessed by needle EMG was associated (P = 0.01) with weaker squeeze pressures (83 ± 10 mmHg vs. 154 ± 30 mmHg) and explained 19% (P = 0.01) of the variation in squeeze pressure. Anal sphincter MUP are longer and more polyphasic in older than younger nulliparous women. Women with FI have more severe neurogenic or muscle anal sphincter injury, which is associated with lower squeeze pressures.

Poster 69 Waiting to Inhale: Electrodiagnosis of A Left Phrenic Nerve Palsy After Chiropractic Cervical Manipulation: A Case Report

Disclosures: C. M. Roque-Dang, none. Patients or Programs: A 50-year-old man. Program Description: The patient had presented with the chief complaint of dyspnea for several months. He reported that he had chiropractic treatment for cervicalgia and, on the day after cervical manipulation, developed unexplained dyspnea with mild exertional activities. Due to his worsening symptoms, he terminated his chiropractic visits and was evaluated by his primary care physician and a neurologist. Pertinent radiographic imaging included a SNIFF fluoroscopic examination, which revealed left hemidiaphragmatic paralysis and a chest radiograph that demonstrated an elevated left hemidiaphragm. Based on the patient’s history and radiographic imaging a electrodiagnostic testing was then performed to rule out a left phrenic nerve palsy. Setting: Outpatient private practice office. Results: On motor nerve conduction studies, he was found to have delayed distal latencies of the left phrenic nerve. Electromyography revealed reduced recruitment throughout the left hemidiaphragm, rare spontaneous denervation potentials in the left lateral diaphragm, and complex and nascent polyphasic single motor unit potentials in the left anterior diaphragm. The electrodiagnostic findings were consistent a left phrenic nerve segmental demyelinated injury. We referred the patient to a plastic surgeon, who performed a left phrenic nerve reconstruction. After surgery, the patient had improved respiratory function and activity tolerance. Discussion: A phrenic nerve injury that resulted in symptomatic diaphragmatic paralysis is most commonly associated with cardiothoracic surgery or malignancy. There are only a few cases that report phrenic nerve palsies sustained from chiropractic cervical manipulation. In these isolated reports, electrodiagnosis was not routinely used to detect these lesions. Conclusions: Reported is an unusual case of unilateral phrenic nerve palsy sustained after chiropractic manipulation. Before receiving cervical spine manipulation, patients should be counseled of this possible and serious complication. Electrodiagnostic studies are useful in phrenic nerve injury diagnosis and treatment determination.