EMG Studies Research Articles

P.073 Transient osteoporosis of the hip during pregnancy associated with EMG signs of acute regional denervation

Background: Transient osteoporosis is an infrequent musculoskeletal condition most often seen in middle-aged males, but can rarely present during late pregnancy in females. Patients present with sudden onset of severe joint pain. MRI typically shows T2 hypersignals and bone marrow edema. Abnormal neurophysiological findings have only rarely been described in the literature. Methods: Case report Results: A 35-year old patient presented at 34 weeks of pregnancy with acute onset of right hip and leg pain. MRI showed marked T2 hypersignals in the head of the femur with distal extension and bone marrow edema pathognomonic of transient osteoporosis. Neurophysiological studies showed normal nerve conductions of the lower extremities, but fibrillation potentials and positive sharp waves were found acutely in proximal muscles of the affected extremity and not limited to a single nerve territory. Inflammatory markers were unremarkable. Treatment was conservative with rest and reduction of weight bearing and pain resolved in the hip, but recurred in the ipsilateral knee several months after delivery suggesting evolution toward regional migratory osteoporosis. Conclusions: Transient osteoporosis of the hip may be associated with EMG signs of denervation that could suggest a contributing neurogenic mechanism. Their prevalence may be underestimated and we suggest considering serial EMG studies in its investigation.

Knee jerk responses in infants at high risk for cerebral palsy: an observational EMG study.

Following our clinical observation of tonic responses in response to the knee jerk in infants at very high risk for cerebral palsy (VHR infants), we systematically studied tonic responses, clonus, and reflex irradiation. We questioned (i) whether these responses occurred more often in VHR infants than in typically developing (TD) infants, and (ii) whether they were associated with abnormal general movement quality. Twenty-four VHR and 26 TD infants were assessed around 3 mo corrected age. Surface electromyograms of leg, trunk, neck, and arm muscles were recorded while eliciting the knee jerk. All assessments were video-recorded. VHR infants more often than TD infants showed tonic responses in the ipsilateral quadriceps and hamstring (Mann-Whitney U; P = 0.0005 and P = 0.0009), clonus (Chi-square; P = 0.0005) and phasic responses in the contralateral quadriceps and hamstring (Mann-Whitney U; P = 0.002 and P = 0.0003, respectively). Widespread reflex irradiation occurred in VHR and TD infants. Definitely abnormal general movements and stiff movements were associated with tonic responses (Mann-Whitney U; P = 0.0005, P = 0.007, respectively) and clonus (Mann-Whitney U; P = 0.003 and P = 0.0005) in the ipsilateral quadriceps. Similar to clonus, tonic responses may be regarded as a marker of a loss of supraspinal control. Reflex irradiation primarily is a neurodevelopmental phenomenon of early ontogeny.

看護動作の筋電図学的分析（その１）:－移動動作モデルの周波数成分－

看護動作の筋電図学的分析（その１）:－移動動作モデルの周波数成分－

ID 57 – End plate spikes or fusimotor spikes

Objective End plate spikes (EPSs) are often recorded in EMG studies. They are usually accompanied by miniature end plate potentials (MEPPs). The origin of EPSs is conjectured to be irritation of a terminal motor nerve twig by the needle electrode. The EPSs are then recorded postsynaptically from the muscle fibre. I suggest another explanation for EPSs. Methods EPSs were recorded from healthy voluntary persons using one or several needle electrodes in parallel with the muscle fibres. We also used local anesthesia of the nerve outside the given muscle. Results EPSs were observed to be usually local, without propagation to other needle electrodes in parallel with the muscle fibres. Some EPSs propagated for a short distance and, rarely, we observed EPSs propagating like motor unit potentials. Local anesthesia suppressed EPSs completely but 80% of the M-response was spared. Passive stretch of the muscle activated EPSs. Conclusions These observations point out that EPSs represent action potentals of intrafusal motor units. Local EPSs reflect junction potentials of nuclear bag fibres and shortly propagating action potentials action potentials of nuclear chain fibres. MUP-like EPSs represent potentals of beta motor units. Stretch activates II-afferents which synapse to gamma and beta motor neurones. Key message EPSs are intrafusal.

Affective responses to ambivalence are context-dependent: A facial EMG study on the role of inconsistency and evaluative context in shaping affective responses to ambivalence

It has long been debated whether attitudinal ambivalence elicits negative affect and evidence for such a link is inconclusive. Using facial EMG, we tested the idea that affective responses to ambivalence are dependent on the inconsistency of evaluations in the current situation. In a person perception task, participants were presented with positive (e.g., friendly, intelligent), negative (e.g., jealous, dominant), or positive and negative information (e.g., intelligent, dominant) about different target persons. When participants were only exposed to the information without having to respond, ambivalent information elicited the same affective response as positive stimuli, participants showed more zygomaticus (positive affect) and less corrugator activation (negative affect) than to negative stimuli (task 1). When participants had to make a choice, ambivalent information elicited the same affective response as negative information (task 2). This was qualified by the possibility to resolve the inconsistency between evaluations. Specifically, ambivalence only led to a relative decrease in positive affect when evaluative context did not help resolve the inconsistency between ambivalent evaluations and created a choice conflict (e.g., “Bob is intelligent and dominant. Do you think Bob is a good collaborator?”). When the same ambivalent information (e.g. “Bob is intelligent and dominant”) was presented in a context in which the opposing evaluations were not inconsistent (e.g., “Do you think Bob can write a good research paper?”), participants reported to experience lower levels of conflict and displayed more positive affect (i.e., more zygomaticus activation). The current data contribute to the reconciliation of previously inconclusive results on affective responses to attitudinal ambivalence. The results suggest that ambivalence only leads to relatively more negative affect (i.e., a decrease in positive affect) when ambivalent information is inconsistent in a current situation and thus creates conflict. Implications of these findings are discussed.

In vivo impact of presynaptic calcium channel dysfunction on motor axons in episodic ataxia type 2.

Ion channel dysfunction causes a range of neurological disorders by altering transmembrane ion fluxes, neuronal or muscle excitability, and neurotransmitter release. Genetic neuronal channelopathies affecting peripheral axons provide a unique opportunity to examine the impact of dysfunction of a single channel subtype in detail in vivo. Episodic ataxia type 2 is caused by mutations in CACNA1A, which encodes the pore-forming subunit of the neuronal voltage-gated calcium channel Cav2.1. In peripheral motor axons, this channel is highly expressed at the presynaptic neuromuscular junction where it contributes to action potential-evoked neurotransmitter release, but it is not expressed mid-axon or thought to contribute to action potential generation. Eight patients from five families with genetically confirmed episodic ataxia type 2 underwent neurophysiological assessment to determine whether axonal excitability was normal and, if not, whether changes could be explained by Cav2.1 dysfunction. New mutations in the CACNA1A gene were identified in two families. Nerve conduction studies were normal, but increased jitter in single-fibre EMG studies indicated unstable neuromuscular transmission in two patients. Excitability properties of median motor axons were compared with those in 30 age-matched healthy control subjects. All patients had similar excitability abnormalities, including a high electrical threshold and increased responses to hyperpolarizing (P < 0.00007) and depolarizing currents (P < 0.001) in threshold electrotonus. In the recovery cycle, refractoriness (P < 0.0002) and superexcitability (P < 0.006) were increased. Cav2.1 dysfunction in episodic ataxia type 2 thus has unexpected effects on axon excitability, which may reflect an indirect effect of abnormal calcium current fluxes during development.

Posture in dentists: Sitting vs. standing positions during dentistry work - an EMG study

Adequate working posture is important for overall health. Inappropriate posture may increase fatigue, decrease efficiency, and eventually lead to injuries. The purpose was to examine posture positions used during dentistry work. In order to quantify different posture positions, we recorded muscle activity and positions of body segments. The position (inclination) data of the back was used to assess two postures: sitting and standing during standard dental interventions. During standard interventions, whether sitting or standing, a tilt of less than 20 degrees was most prevalent in the forward and lateral flexion directions. Amplitude of electromyography signals corresponding to the level of muscle activity were higher in sitting compared with the electromyography in standing position for all muscle groups on the left and right side of the body. Significant difference between muscle activity in two working postures was evident in splenius capitis muscle on the left (p = 0.032), on the right side of the body (p = 0.049) and in muscle activity of mastoid muscle on the left side (p = 0.029). These findings show that risk for increased fatigue and possible injures can be reduced by combining the sitting and standing occupational postures.

Guillain-Barre Syndrome with Lymphocytic Pleocytosis of the CSF

Introduction: Guillain-Barre typically presents as a symmetric ascending weakness with areflexia. The cerebrospinal fluid typically shows albuminocytologic dissociation. In this case, we present an atypical presentation of severe Guillain-Barre with cerebrospinal fluid exhibiting lymphocytic pleocytosis. Case report: 60-year-old man presented with progressive lower- extremity weakness that progressed to involve respiratory failure and areflexia over several weeks. Electromyography showed both demyelinating and axonal features. Lumbar puncture revealed a lymphocytic pleocytosis. Given the abnormalities on these tests with a clinical picture of Guillain-Barre the patient underwent extensive paraneoplastic testing and full neuro-axis imaging. Imaging revealed abnormal enhancement of ventral and dorsal nerve roots which is consistent with Guillain-Barre. Conclusion: In conclusion, a diagnosis of Guillain-Barre syndrome may still be considered in a patient with clinical findings and EMG studies consistent with GBS but with a CSF profile that does not show the typical albuminocytologic dissociation. However, all other causes of CSF lymphocytic pleocytosis must be ruled out before coming to this conclusion.

Critically re-evaluating a common technique: Accuracy, reliability, and confirmation bias of EMG.

(1) To assess the diagnostic accuracy of EMG in radiculopathy. (2) To evaluate the intrarater reliability and interrater reliability of EMG in radiculopathy. (3) To assess the presence of confirmation bias in EMG. Three experienced academic electromyographers interpreted 3 compact discs with 20 EMG videos (10 normal, 10 radiculopathy) in a blinded, standardized fashion without information regarding the nature of the study. The EMGs were interpreted 3 times (discs A, B, C) 1 month apart. Clinical information was provided only with disc C. Intrarater reliability was calculated by comparing interpretations in discs A and B, interrater reliability by comparing interpretation between reviewers. Confirmation bias was estimated by the difference in correct interpretations when clinical information was provided. Sensitivity was similar to previous reports (77%, confidence interval [CI] 63%-90%); specificity was 71%, CI 56%-85%. Intrarater reliability was good (κ 0.61, 95% CI 0.41-0.81); interrater reliability was lower (κ 0.53, CI 0.35-0.71). There was no substantial confirmation bias when clinical information was provided (absolute difference in correct responses 2.2%, CI -13.3% to 17.7%); the study lacked precision to exclude moderate confirmation bias. This study supports that (1) serial EMG studies should be performed by the same electromyographer since intrarater reliability is better than interrater reliability; (2) knowledge of clinical information does not bias EMG interpretation substantially; (3) EMG has moderate diagnostic accuracy for radiculopathy with modest specificity and electromyographers should exercise caution interpreting mild abnormalities. This study provides Class III evidence that EMG has moderate diagnostic accuracy and specificity for radiculopathy.

Dopaminergic medicines are drugs of choice for medicament-resistant facial nerve neuropathy: EMG study

Dopaminergic medicines are drugs of choice for medicament-resistant facial nerve neuropathy: EMG study

Electromyographic and laboratory findings in acute Solanum torvum poisoning*

Context: Solanum torvum berries, known as susumber or turkey berries, are prepared as part of traditional Jamaican dishes usually served with cod and rice. Poisoning is rare. Although toxic compounds have never been definitively isolated, previous reports suggest toxicity results from inhibition of acetylcholinesterases. We present a case of susumber berry poisoning with detailed electromyographic studies and laboratory analysis.Case details: A 54-year-old woman presented to the Emergency Department (ED) complaining of vision, speech, and gait changes; emesis; and diffuse myalgias following consumption of susumber berries. The physical examination demonstrated an intact, lucid mental status, miosis, opsoclonus, severe dysarthria, dysmetria, mild extremity tenderness and weakness, and inability to ambulate. Her symptom constellation was interpreted as a stroke.Discussion: Electromyography demonstrated a pattern of early full recruitment as well as myotonia during the period of acute toxicity. Additionally, solanaceous compounds, in particular solasonine and solanidine, were identified in leftover berries and the patient’s serum. Store-bought commercial berries and subsequent serum samples were free of such toxic compounds. EMG studies, together with a laboratory analysis of berries or serum can assist in the differential diagnosis of stroke, and provide both a prognostic screening and confirmation of suspected glycoside toxicity.

Peripheral neuropathy in patients with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency - A follow-up EMG study of 12 patients.

The neonatal screening and early start of the dietary therapy have improved the outcome of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD). The acute symptoms of LCHADD are hypoketotic hypoglycemia, failure to thrive, hepatopathy and rhabdomyolysis. Long term complications are retinopathy and neuropathy. Speculated etiology of these long term complications are the accumulation and toxicity of hydroxylacylcarnitines and long-chain fatty acid metabolites or deficiency of essential fatty acids. To study the possible development of polyneuropathy in LCHADD patients with current dietary regimen. Development of polyneuropathy in 12 LCHADD patients with the homozygous common mutation c.G1528C was evaluated with electroneurography (ENG) studies. The ENG was done 1-12 times to each patient, between the ages of 3 and 40 years. Clinical data of the patients were collected from the patient records. The first sign of polyneuropathy was detected between the ages of 6-12 years, the first abnormality being reduction of the sensory amplitudes of the sural nerves. With time, progression was detected by abnormalities in sensory responses extending to upper limbs, as well as abnormalities in motor responses in lower limbs. Altogether, eight of the patients had polyneuropathy, despite good compliancy of the diet. This study is the first to report the evolution of polyneuropathy with clinical neurophysiological methods in a relative large LCHADD patient group. Despite early start, and good compliance of the therapy, 6/10 of the younger patients developed neuropathy. However, in most patients the polyneuropathy was less severe than previously described.

Emotional facial expressions evoke faster orienting responses, but weaker emotional responses at neural and behavioural levels compared to scenes: A simultaneous EEG and facial EMG study

In the current study, electroencephalography (EEG) was recorded simultaneously with facial electromyography (fEMG) to determine whether emotional faces and emotional scenes are processed differently at the neural level. In addition, it was investigated whether these differences can be observed at the behavioural level via spontaneous facial muscle activity. Emotional content of the stimuli did not affect early P1 activity. Emotional faces elicited enhanced amplitudes of the face-sensitive N170 component, while its counterpart, the scene-related N100, was not sensitive to emotional content of scenes. At 220–280ms, the early posterior negativity (EPN) was enhanced only slightly for fearful as compared to neutral or happy faces. However, its amplitudes were significantly enhanced during processing of scenes with positive content, particularly over the right hemisphere. Scenes of positive content also elicited enhanced spontaneous zygomatic activity from 500–750ms onwards, while happy faces elicited no such changes. Contrastingly, both fearful faces and negative scenes elicited enhanced spontaneous corrugator activity at 500–750ms after stimulus onset. However, relative to baseline EMG changes occurred earlier for faces (250ms) than for scenes (500ms) whereas for scenes activity changes were more pronounced over the whole viewing period. Taking into account all effects, the data suggests that emotional facial expressions evoke faster attentional orienting, but weaker affective neural activity and emotional behavioural responses compared to emotional scenes.

Editorial: What can we make of theories of embodiment and the role of the human mirror neuron system?

Editorial: What can we make of theories of embodiment and the role of the human mirror neuron system?

G.P.315 - Coexisting TIA1 and MYH7 distal myopathy

Distal myopathies are genetically heterogeneous. TIA1 mutations cause Welander distal myopathy. MYH7 mutations result in various clinical phenotypes, including Laing distal myopathy, myosin storage myopathy and hypertrophic/dilated cardiomyopathy. We describe a family affected by distal myopathy and variable presence of cardiomyopathy due to coexisting TIA1 and MYH7 mutations. The propositus is a 67-year-old woman of Swedish and Greek descent with history of easy tripping since childhood who has experienced a stepwise progression of asymmetric distal limb weakness in the past 20 years. Neurological examination revealed mild to severe asymmetric distal lower >upper limb weakness. CK value was normal. EMG study showed myopathic changes with minimal fibrillation potentials and myotonic discharges. Biopsy of the extensor carpi radialis muscle showed: rare rimmed vacuoles, minicore-like structures and congophilic inclusions; few necrotic and regenerating fibers; fiber splitting; increased internal nuclei; and fiber type grouping. There was no cardiac involvement by ECG and echocardiogram. Her 66-year-old sister has 8 years of mild distal limb weakness, supraventricular tachycardia and hypertrophic cardiomyopathy documented by echocardiogram and MRI. Another sibling has distal weakness while parents were asymptomatic. Both sisters carry a known pathogenic heterozygous TIA1 mutation (p.Glu384Lys) and a rare heterozygous MYH7 variant (c.5459G > A; p.Arg1820Gln), which involves a highly conserved residue and is predicted to be pathogenic. Because a homozygous MYH7 mutation (p.Arg1820Trp) was reported in recessive myosin storage myopathy, aCGH deletion/duplication analysis of MYH7 was performed in the proband and it was normal. The clinical phenotype is dictated by the coexistent TIA1 and MYH7 mutations, which can result in similar pathological findings. The proband's early onset of distal leg weakness and the sister's cardiomyopathy support the pathogenicity of the MYH7.

The occurrence frequency: A suitable parameter for the evaluation of the myoelectric activity during walking.

Many studies have recently addressed the quantification of the natural variability of myoelectric activity during walking, considering hundreds of strides. The availability of so many strides allows assessing a parameter seldom considered in classic surface EMG (sEMG) studies: the occurrence frequency, defined as the frequency each muscle activation occurs with, quantified by the number of strides in which a muscle is recruited with that specific activation modality. Aim of this study is to point out the occurrence frequency as a suitable parameter for the evaluation of the variability of the myoelectric activity during walking. This goal was pursued by means of the statistical gait analysis of sEMG signal acquired from Gastrocnemius Lateralis (GL) in six healthy subjects, with different characteristics. Results show that among these six subjects relevant differences were not detected in the temporal parameters, i.e., activation onset/offset instant and activation duration. In the same subjects, the values of the occurrence frequency ranged from 3% to 74% in the different activation modalities, indicating a large variability of this parameter. These findings show that occurrence frequency is able to provide further and different information with respect to classical temporal parameters. Thus, the occurrence frequency is proposed as a suitable parameter to support the classic temporal parameters in the evaluation of variability of myoelectric activity during walking.

Sciatic nerve injection injury in children: Management and outcome

Background: Sciatic nerve injury is a common complication following IM gluteal injection in children. A controversy still exists regarding management and outcome.Objective: To find the outcome of conservative and surgical treatment and compare it with other studies.Patients and Methods: This is a retrospective study of 24 children( less than 15 years old) with sciatic nerve injection injury at the gluteal region. The child age, gender, type of injection drug, time of injury with complete neurological examination and EMG study were recorded. Conservative treatment including physiotherapy and surgical treatment including surgical exploration and neurolysis at the buttock region were done with follow-up 6 months to one year.Results: Patient’s age ranged from 6 months to 15 years; there were 18 male and 6 female. The most common IM drugs are analgesic in 40% and antibiotic in 18%. Neurological complaint was 22 foot drop (33.3%) and pain in 2 patient (8.7%). Surgery was done in 16 cases (66.6%) and 8 patients (33.3%) were treated conservatively . Outcome of surgery was good in (62.5%) and poor in (37.5).Conclusions: we recommend surgery 2-3 months after conservative treatment including physiotherapy, analgesia, and EMG follow up, if no neurological recovery occurred. The outcome of surgery was good in the child with sciatic nerve injection injury

Differences in age-related fiber atrophy between vastii muscles of active subjects: a multichannel surface EMG study

The aim of the study was to non-invasively determine if vastus lateralis (VL) and vastus medialis obliquus (VM) muscles are equally affected by age-related fiber atrophy. Multichannel surface electromyography was used since it allows to estimate muscle fiber conduction velocity (CV), which has been demonstrated to be related to the size of recruited muscle fibers. Twelve active elderly men (age 69 ± 4 years) and 12 active young men (age 23 ± 2 years) performed isometric knee extension at 30%, 50%, and 70% of maximal voluntary contraction. Electromyographic signals were recorded from VL and VM muscles of the dominant limb using arrays with eight electrodes and CVs were estimated for each contraction. CV estimates showed a different behavior in the two muscles: in VL at 50% and 70% of maximum voluntary contraction they were greater in young than in elderly; whereas such a difference was not observed in VM. This finding suggest that in active elderly VM seems to be less affected by the age-related fibers atrophy than VL. Hence, the common choice of studying VL as a muscle representative of the whole quadriceps could generate misleading findings. Indeed, it seemed that the sarcopenic ageing effects might be heterogeneous within quadriceps muscle.

E-Norms

Collecting reference values in subpopulations such as infants and children can pose a daunting challenge to gather through epidemiologic studies. The authors propose to evaluate a method the authors refer to as extrapolated norms (e-norms) to derive Stimulated Single Fiber EMG jitter reference values from the laboratory data of pediatric and adult cohorts. Single Fiber EMG studies are considered the gold standard test for evaluation of neuromuscular transmission disorders. Data that lie in the plateau part of an inverted S curve derived from sorted jitter data were used to calculate descriptive statistics for pediatric and adult e-norms jitter. The e-norms derived jitter was 22 ± 2.83 μs for our pediatric and 21 ± 2.79 μs for our adult cohort. Our adult e-norms values compared favorably with the 22 ± 1.99 μs published jitter range derived from a healthy adult cohort. The e-norms method the authors describe seems to be useful in recovering reference ranges when such values are difficult to obtain, such as in a pediatric subpopulation.

OP10 – 2707: Childhood-onset ataxic gait solved by muscle biopsy

Objective The differential diagnosis of childhood-onset ataxia may be challenging, especially in the absence of brain MRI or lab abnormalities. We present a case where the findings of intra-axonal spheroids on muscle biopsy led to the diagnosis of atypical neuraxonal dystrophy (NAD) due to a compound heterozygous mutation in PLA2G6. Methods and results The proband was referred for frequent falls at age 4 years. Acquisition of early developmental milestones was normal. Concerns were first expressed at age 3 years, when she developed an unsteady gait. On examination eye movements were slightly saccadic, gait ataxic, balance poor. She had mild proximal muscle weakness with positive sign of Gowers. Deep tendon reflexes were present. She was at times introverted and sometimes overfamiliar. Formal evaluation of development showed normal intelligence, normal speech and language development except for intermittent whispering, and confirmed poor coordination and balance. Visuo-spatial skills were normal. Brain MRI was normal and remained so after 3 years. EMG and nerve conduction studies, fundoscopy, lactate, alpha-foetoprotein and urinary catecholamines were normal. Friedreich ataxia and Pompe disease were excluded. Further concern about a possible myopathy led to muscle biopsy. Histological examination showed a predominance of type1 fibers. Extensive immunohistochemical testing was normal. Electron microscopy revealed intra-axonal spheroids in the peri- and endomysial myelinated nerve bundles as well as in the motor endplates. Neuroaxonal spheroids are present in >80% of cases with PLA2G6-associated neurodegeneration (PLAN) and is rarely seen in mitochondrial protein associated neurodegeneration (MPAN). Mutation analysis of PLA2G6 showed the compound heterozygous presence of the c.1021G>A (p.Ala341Thr) and c.2036G>T (p.Gly679Val) mutations in the patient, while both parents were heterozygous carriers, confirming the diagnosis of atypical NAD. Conclusion This report highlights that childhood-onset gait ataxia with subtle behavioral and/or expressive speech abnormalities may be the presenting features of atypical NAD. The differential diagnosis of childhood-onset ataxia may be challenging, especially in the absence of brain MRI or lab abnormalities. We present a case where the findings of intra-axonal spheroids on muscle biopsy led to the diagnosis of atypical neuraxonal dystrophy (NAD) due to a compound heterozygous mutation in PLA2G6. The proband was referred for frequent falls at age 4 years. Acquisition of early developmental milestones was normal. Concerns were first expressed at age 3 years, when she developed an unsteady gait. On examination eye movements were slightly saccadic, gait ataxic, balance poor. She had mild proximal muscle weakness with positive sign of Gowers. Deep tendon reflexes were present. She was at times introverted and sometimes overfamiliar. Formal evaluation of development showed normal intelligence, normal speech and language development except for intermittent whispering, and confirmed poor coordination and balance. Visuo-spatial skills were normal. Brain MRI was normal and remained so after 3 years. EMG and nerve conduction studies, fundoscopy, lactate, alpha-foetoprotein and urinary catecholamines were normal. Friedreich ataxia and Pompe disease were excluded. Further concern about a possible myopathy led to muscle biopsy. Histological examination showed a predominance of type1 fibers. Extensive immunohistochemical testing was normal. Electron microscopy revealed intra-axonal spheroids in the peri- and endomysial myelinated nerve bundles as well as in the motor endplates. Neuroaxonal spheroids are present in >80% of cases with PLA2G6-associated neurodegeneration (PLAN) and is rarely seen in mitochondrial protein associated neurodegeneration (MPAN). Mutation analysis of PLA2G6 showed the compound heterozygous presence of the c.1021G>A (p.Ala341Thr) and c.2036G>T (p.Gly679Val) mutations in the patient, while both parents were heterozygous carriers, confirming the diagnosis of atypical NAD. This report highlights that childhood-onset gait ataxia with subtle behavioral and/or expressive speech abnormalities may be the presenting features of atypical NAD.