Upper Motor Neuron Signs Research Articles

Conus myelitis associated with Covid 19 infection – a rare complication

Covid 19 pandemic has taken away millions of lives. Our understanding of this disease, till to date, is not complete. This disease has a wide variety of neurological manifestations. Acute transverse myelitis is one such rare neurological complication of Covid 19. The exact etiology is not clear. Auto immunity might be one of the possible mechanisms. We report a case of 39-year-old lady, who had recent history of high-grade fever and cough. This was followed by weakness of both legs and in- ability to pass urine. SARS-CoV-2 (PCR) from nasopharyngeal swab was positive. She was found to have features of acute non compressive myelopathy. MRI brain and MRI cervical spine with contrast was normal. MRI dorso lumbar spine with contrast was suggestive of diffuse hyper intensity of conus medullaris with contrast enhancement suggestive of conus myelitis. CSF analysis ruled out infection and autoimmune causes. She was pulsed with high dose steroids. There was some transient improvement in symptoms. Learning points: 1) Physicians should not consider Covid as a respiratory illness only. It can present with a variety of extra pulmonary manifestations. 2) Acute transverse myelitis is a rare complication of Covid 19 infection. Timely recognition and treatment can prevent permanent neurological damage and residual disability. 3) Conus myelitis might not present with classic upper motor neuron signs. Any new onset bladder dysfunction in a setting of a recent covid infection should be taken seriously and requires urgent imaging of the spine.

Far Lateral Approaches: Dural Arteriovenous Fistulae at the Hypoglossal Canal: 3-Dimensional Operative Video.

Cognard type V dural arteriovenous fistulae (dAVF) are typically located at the foramen magnum. Their presentation often mimics that of cervical myelopathy, and they can be easily misdiagnosed even if spinal vascular imaging is undertaken. Treatment typically involves endovascular embolization or surgery when embolization is not possible. We describe a case of a 67-yr-old man who presented with progressive symptoms of cervical myelopathy with a significant reduced ambulation and upper motor neuron signs. Imaging disclosed upper cervical cord edema, and angiography confirmed a Cognard type V dAVF with drainage into the perimedullary and spinal venous system. The dAVF was supplied by the hypoglossal division of the ascending pharyngeal artery. Endovascular treatment was believed to pose a risk of ischemic injury to the hypoglossal nerve, and therefore, surgery was offered. Informed consent was obtained. A far lateral approach was used to access the fistulous point. We describe the relevant vascular anatomy and the benefits of the far lateral approach for this lesion. We also demonstrate a tailored inferior condylectomy to gain access to the intracranial part of the hypoglossal canal, where the draining vein is expected to be found. We supplement the discussion with a 3D surgical video.

Case report: \u201can unexpected origin of coma in a young adult\u201d

We report a peculiar case of acute non-traumatic coma due to neuromuscular hypoventilation syndrome caused by a non-traumatic spinal cord injury (NTSCI). A 21-year-old patient presented to the emergency room complaining of sudden onset weakness in his lower limbs and shortness of breath. While in the ER, he briefly became comatose and labs revealed an acute respiratory acidosis. Detailed neurologic examination ultimately revealed upper motor neuron signs and quadriplegia. He was ultimately diagnosed with a non-traumatic spinal cord injury, in particular, a cervical transverse myelitis which had caused acute diaphragmatic weakness. Although a very rare cause of coma, emergency medicine physicians need to be aware of transverse myelitis, a disorder that may result in rapidly progressive neurologic decline and is treated with immunomodulation.

Sensitivity of brain MRI and neurological examination for detection of upper motor neurone degeneration in amyotrophic lateral sclerosis

ObjectivesTo investigate sensitivity of brain MRI and neurological examination for detection of upper motor neuron (UMN) degeneration in patients with amyotrophic lateral sclerosis (ALS).MethodsWe studied 192 patients with ALS and...

Right Lower Extremity Pain With Full Bladder--pilates/dance

HISTORY: A 56-year-old dancer with uterine fibroids and history of ACL repair 2016 presented with 4 years of right lower extremity pain that began while she was immobilized following her ACL reconstruction. She describes her pain as either sharp or numb, radiating from the posterior proximal thigh into her leg, heel, and plantar aspect of her foot. Her pain is consistently aggravated by a full bladder and resolves after voiding, though can be noted with sit to stand transfers and prolonged sitting. Due to the severity of her pain, she will awake in the evenings and actively avoids hydration to prevent her pain. She notes R calf atrophy since ACL repair. Denies incontinence, difficulty sleeping, unintended weight change, or falling. PHYSICAL EXAMINATION: She had a protuberant, nondistended abdomen, normal gait, strength, sensation, and reflexes with no upper motor neuron signs. She had full and painless range of motion of the spine and hips, nontender spine and lower extremities, and negative special testing for piriformis and sacroiliac and hip joints. DIFFERENTIAL DIAGNOSIS: L5 or S1 radiculopathy Lumbosacral plexopathy Sciatic mononeuropathy TESTS AND RESULTS: XR hip: bilateral CAM lesions, mild osteoarthrosis, calcific fibroids.MR Pelvis: Enlarged fibroid uterus. MR lumbar spine and plexus: Cord, conus, and cauda equina appear normal. No stenosis. Enlarged fibroid uterus with displacement of the lumbosacral plexus posterolaterally on both sides without abnormal enhancement. Symmetric muscle bulk. FINAL WORKING DIAGNOSIS: Lumbosacral Plexopathy due to Mass Effect of Fibroids and Full Bladder. TREATMENT AND OUTCOMES: The patient opted to postpone surgery based on her personal preference and lack of neuromuscular decline.

Early diagnosis of amyotrophic lateral sclerosis by threshold tracking and conventional transcranial magnetic stimulation.

Background and purposeShort‐interval intracortical inhibition by threshold tracking (T‐SICI) has been proposed as a diagnostic tool for amyotrophic lateral sclerosis (ALS) but has not been compared directly with conventional amplitude measurements (A‐SICI). This study compared A‐SICI and T‐SICI for sensitivity and clinical usefulness as biomarkers for ALS.MethodsIn all, 104 consecutive patients referred with suspicion of ALS were prospectively included and were subsequently divided into 62 patients with motor neuron disease (MND) and 42 patient controls (ALS mimics) by clinical follow‐up. T‐SICI and A‐SICI recorded in the first dorsal interosseus muscle (index test) were compared with recordings from 53 age‐matched healthy controls. The reference standard was the Awaji criteria. Clinical scorings, conventional nerve conduction studies and electromyography were also performed on the patients.ResultsMotor neuron disease patients had significantly reduced T‐SICI and A‐SICI compared with the healthy and patient control groups, which were similar. Sensitivity and specificity for discriminating MND patients from patient controls were high (areas under the receiver operating characteristic curves 0.762 and 0.810 for T‐SICI and A‐SICI respectively at 1–3.5 ms). Paradoxically, T‐SICI was most reduced in MND patients with the fewest upper motor neuron (UMN) signs (Spearman ρ = 0.565, p = 4.3 × 10−6).ConclusionsAmplitude‐based measure of cortical inhibition and T‐SICI are both sensitive measures for the detection of cortical involvement in MND patients and may help early diagnosis of ALS, with T‐SICI most abnormal before UMN signs have developed. The gradation in T‐SICI from pathological facilitation in patients with minimal UMN signs to inhibition in those with the most UMN signs may be due to progressive degeneration of the subset of UMNs experiencing facilitation.

The Upper Motor Neuron-Improved Knowledge from ALS and Related Clinical Disorders.

Upper motor neuron (UMN) is a term traditionally used for the corticospinal or pyramidal tract neuron synapsing with the lower motor neuron (LMN) in the anterior horns of the spinal cord. The upper motor neuron controls resting muscle tone and helps initiate voluntary movement of the musculoskeletal system by pathways which are not completely understood. Dysfunction of the upper motor neuron causes the classical clinical signs of spasticity, weakness, brisk tendon reflexes and extensor plantar response, which are associated with clinically well-recognised, inherited and acquired disorders of the nervous system. Understanding the pathophysiology of motor system dysfunction in neurological disease has helped promote a greater understanding of the motor system and its complex cortical connections. This review will focus on the pathophysiology underlying progressive dysfunction of the UMN in amyotrophic lateral sclerosis and three other related adult-onset, progressive neurological disorders with prominent UMN signs, namely, primary lateral sclerosis, hereditary spastic paraplegia and primary progressive multiple sclerosis, to help promote better understanding of the human motor system and, by extension, related cortical systems.

O-MN002. Assessment of upper motor neuron function utilizing threshold tracking transcranial magnetic stimulation in amyotrophic lateral sclerosis

Introduction . Upper motor neuron signs are mainly assessed by clinical examinations. Threshold tracking transcranial magnetic stimulation (TT-TMS) can precisely investigate motor cortical function and has been reported as a diagnostic marker in amyotrophic lateral sclerosis (ALS). The correlation between TT-TMS and clinical and neurophysiological findings were examined. Methods . TT-TMS was performed in 30 ALS patients and 26 healthy controls (HC), measured in the abductor pollicis brevis (APB) muscle. Clinical factors, such as age, gender, disease duration, site of onset, upper motor neuron (UMN) sign scores and ALS functional rating scale revised (ALSFRS-R) and a neurophysiological index, such as compound muscle action potential (CMAP) amplitude, measured in the APB muscle, were analyzed with TT-TMS findings. Results . Of 30 patients, 13 were male, and 10 were bulbar onset. The mean age was 69 years old, and the mean disease duration was 19 months. Averaged short interval intracortical inhibition (SICI) (1-7 ms) was decreased in ALS (p < 0.01), compared with HC. Averaged SICI (1-7 ms) was not related to age, gender, disease duration, site of onset, UMN sign scores, ALSFRS-R and CMAP amplitudes. Decreased SICI was unveiled even in 4 patients, without evident upper motor neuron signs. Conclusion . TT-TMS found motor cortical dysfunction in ALS, but the relationship between SICI and UMN signs was not evident. Progress of cortical hyperexcitability and pyramidal tract lesion may not be parallel in ALS. Additionally, muscle atrophies might hamper detection of UMN signs. Further studies are necessary to discuss usefulness of TT-TMS as a UMN sign marker in ALS.

Whole-Spine Magnetic Resonance Imaging: A Review of Suggested Indications.

The spinal column has a propensity for lesions to manifest in a multifocal manner, and identification of the lesions can be difficult. When used to image the spine, magnetic resonance imaging (MRI) most accurately identifies the presence and location of lesions, guiding the treatment plan and preventing potentially devastating complications that are known to be associated with unidentified lesions. Certain conditions clearly warrant evaluation with whole-spine MRI, whereas the use of whole-spine MRI with other conditions is more controversial. We suggest whole-spine MRI when evaluating and treating any spinal infection, lumbar stenosis with upper motor neuron signs, ankylosing disorders of the spine with concern for fracture, congenital scoliosis undergoing surgical correction, and metastatic spinal tumors. Use of whole-spine MRI in patients with idiopathic scoliosis and acute spinal trauma remains controversial.

Progressive Neurochemical Abnormalities in Cognitive and Motor Subgroups of Amyotrophic Lateral Sclerosis: A Prospective Multicenter Study.

To evaluate progressive cerebral degeneration in amyotrophic lateral sclerosis (ALS) by assessing alterations in N-acetylaspartate (NAA) ratios in the motor and prefrontal cortex within clinical subgroups of ALS. Seventy-six patients with ALS and 59 healthy controls were enrolled in a prospective, longitudinal, multicenter study in the Canadian ALS Neuroimaging Consortium. Participants underwent serial clinical evaluations and magnetic resonance spectroscopy at baseline and 4 and 8 months using a harmonized protocol across 5 centers. NAA ratios were quantified in the motor cortex and prefrontal cortex. Patients were stratified into subgroups based on disease progression rate, upper motor neuron (UMN) signs, and cognitive status. Linear mixed models were used for baseline and longitudinal comparisons of NAA metabolite ratios. Patients with ALS had reduced NAA ratios in the motor cortex at baseline (p < 0.001). Ratios were lower in those with more rapid disease progression and greater UMN signs (p < 0.05). A longitudinal decline in NAA ratios was observed in the motor cortex in the rapidly progressing (p < 0.01) and high UMN burden (p < 0.01) cohorts. The severity of UMN signs did not change significantly over time. NAA ratios were reduced in the prefrontal cortex only in cognitively impaired patients (p < 0.05); prefrontal cortex metabolites did not change over time. Progressive degeneration of the motor cortex in ALS is associated with more aggressive clinical presentations. These findings provide biological evidence of variable spatial and temporal cerebral degeneration linked to the disease heterogeneity of ALS. The use of standardized imaging protocols may have a role in clinical trials for patient selection or subgrouping. This study provides Class II evidence that MRS NAA metabolite ratios of the motor cortex are associated with more rapid disease progression and greater UMN signs in patients with ALS. ClinicalTrials.gov Identifier: NCT02405182.

A novel homozygous MSTO1 mutation in Ashkenazi Jewish siblings with ataxia and myopathy.

MSTO1 is a cytoplasmic protein that modulates mitochondrial dynamics by promoting mitochondrial fusion. Mutations in the MSTO1 gene are responsible for an extremely rare condition characterized by early-onset myopathy and cerebellar ataxia. We report here two siblings from a large Ashkenazi Jewish family, presenting with a progressive neuromuscular disease characterized by ataxia and myopathy. By whole exome sequencing, we found a novel homozygous missense mutation (c.1403T>A, p.Leu468Gln) in MSTO1. Studies performed on fibroblasts from the index patient demonstrated the pathogenic role of the identified variant; we found that MSTO1 protein level was reduced and that mitochondrial network was fragmented or formed enlarged structures. Moreover, patient's cells showed reduced mitochondrial DNA amount. Our report confirms that MSTO1 mutations are typically recessive, and associated with clinical phenotypes characterized by early-onset muscle impairment and ataxia, often with upper motor neuron signs and varied cognitive impairment.

Upper Motor Neuron Signs in the Cervical Region of Patients With Flail Arm Syndrome.

Objective: We investigated upper motor neuron (UMN) signs in the cervical region in a Chinese clinic-based cohort of patients with flail arm syndrome (FAS) by clinical examination and neurophysiological tests such as triple stimulation technique (TST) and pectoralis tendon reflex testing.Methods: A total of 130 consecutive FAS patients from Peking University Third Hospital underwent physical examination and neurophysiological tests at baseline and 3 months, 6 months, 9 months, and 12 months later. Pyramidal signs, pectoralis tendon reflex and TST results were evaluated to estimate the function of cervical spinal UMNs.Results: At the first visit, weakness of the bilateral proximal upper limbs was found in 99 patients, while weakness of a single proximal upper limb was found in 31 patients. There were 49 patients with tendon hyperreflexia, 42 patients with tendon hyporeflexia and 39 patients with tendon areflexia. All except 4 of the patients had brisk pectoralis tendon reflex. The UMN score of the cervical region was 1.7 ± 0.4, and the lower motor neuron score of that region was 3.5 ± 0.3. The TSTtest/TSTcontrol amplitude ratio was 65.7 ± 7.5%. The latency of quantitative detection of the pectoralis tendon reflex was 7.7 ± 1.2 ms. In the follow-up study, the UMN score and the TSTtest/TSTcontrol amplitude ratio decreased, while the lower motor neuron score increased, and the latency of quantitative detection of the pectoralis tendon reflex remained steady.Conclusion: Although the signs of cervical spinal UMN dysfunction in patients with FAS were often concealed by muscle atrophy in the progression of the disease, TST and pectoralis tendon reflex could reveal it.

Degenerative cervical myelopathy presenting as subjective lower limb weakness could be a trap towards misdiagnosis

When patients presenting with subjective lower limb weakness (SLLW) are encountered, it is natural to suspect a lumbar pathology and proceed with related clinical examination, investigations and management. However, SLLW could be a sign of degenerative cervical myelopathy (DCM) due to an evolving cord compression. In such circumstances, if symptoms are not correlated to myelopathy at the earliest, there could be potential complications over time. In this study, we intend to analyse the outcomes after surgical management of the cervical or thoracic cord compression in patients with SLLW. Retrospectively, patients who presented to our center during the years 2010–2016 with sole complaint of bilateral SLLW but radiologically diagnosed to have a solitary cervical or thoracic stenosis, or tandem spinal stenosis and underwent surgical decompression procedures were selected. Their clinical presentation was categorised into three types, myelopathy was graded using Nurick’s grading and JOA scoring; in addition, their lower limb functional status was assessed using the lower extremity functional scale (LEFS). Functional recovery following surgery was assessed at 6 weeks, 3 months, 6 months, one year, and two years. Selected patients (n = 24; Age, 56.4 ± 10.1 years; range 32–78 years) had SLLW for a period of 6.4 ± 3.2 months (range 2–13 months). Their preoperative JOA score was 11.3 ± 1.8 (range 7–15), and LEFS was 34.4 ± 7.7 (range 20–46). Radiological evidence of a solitary cervical lesion and tandem spinal stenosis was found in 6 and 18 patients respectively. Patients gradually recovered after surgical decompression with LEFS 59.8 ± 2.7 (range 56–65) at 1 year and JOA score 13.6 ± 2.7 (range − 17 to 100) at 2 years. The recovery rate at final follow up was 47.5%. Our results indicate the importance of clinically suspecting SLLW as an early non-specific sign of DCM to avoid misdiagnosis, especially in patients without conventional upper motor neuron signs. In such cases, surgical management of the cord compression resulted in significant functional recovery and halted the progression towards permanent disability.

Clinical, Genetic, and Disability Profile of Pediatric Distal Hereditary Motor Neuropathy.

To describe the clinical, genetic, and disability profile of pediatric distal hereditary motor neuropathy (dHMN) and to determine the utility of an outcome measure validated for children with Charcot-Marie-Tooth disease (CMT) in assessing disability in this cohort. We reviewed the clinical, neurophysiologic, and disability data on individuals with dHMN, evaluated before the age of 20 years, at 2 tertiary neuromuscular clinics in Australia and Spain. Disability was assessed annually with the CMT Pediatric Scale (CMTPedS) in a subset of individuals. Twenty-two children (13 female) from 19 families were included. Fourteen individuals were symptomatic in the first year of life. Intellectual disability was present in 6 individuals; upper motor neuron signs were seen in 8. Pathogenic variants were found in 9 families, more frequently in BICD2 (BICD2-4, DYNC1H1-2, MFN2-2, GARS-1). A novel pathogenic variant in the GARS gene was detected and characterized phenotypically. Disability was moderate on the CMTPedS (mean [SD] 18.2 [6.3], n = 16), with balance and long jump being the most affected and sensation items and grip strength the least affected. Over 1 year, the CMTPedS total score deteriorated, on average 1.5 points (SD 3.7) or 9% (n = 12), with significant variability in the rate of progression within the cohort. The genetic profile of pediatric dHMN is different from that identified in adult cohorts. This study has identified distinct functional limitations for the CMTPedS in children and adolescents with dHMN.

Dissociated leg muscle atrophy in amyotrophic lateral sclerosis/motor neuron disease: the \u2018split-leg\u2019 sign

Disproportionate muscle atrophy is a distinct phenomenon in amyotrophic lateral sclerosis (ALS); however, preferentially affected leg muscles remain unknown. We aimed to identify this split-leg phenomenon in ALS and determine its pathophysiology. Patients with ALS (n = 143), progressive muscular atrophy (PMA, n = 36), and age-matched healthy controls (HC, n = 53) were retrospectively identified from our motor neuron disease registry. We analyzed their disease duration, onset region, ALS Functional Rating Scale-Revised Scores, and results of neurological examination. Compound muscle action potential (CMAP) of the extensor digitorum brevis (EDB), abductor hallucis (AH), and tibialis anterior (TA) were reviewed. Defined by CMAPEDB/CMAPAH (SIEDB) and CMAPTA/CMAPAH (SITA), respectively, the values of split-leg indices (SI) were compared between these groups. SIEDB was significantly reduced in ALS (p < 0.0001) and PMA (p < 0.0001) compared to the healthy controls (HCs). SITA reduction was more prominent in PMA (p < 0.05 vs. ALS, p < 0.01 vs. HC), but was not significant in ALS compared to the HCs. SI was found to be significantly decreased with clinical lower motor neuron signs (SIEDB), while was rather increased with clinical upper motor neuron signs (SITA). Compared to the AH, TA and EDB are more severely affected in ALS and PMA patients. Our findings help to elucidate the pathophysiology of split-leg phenomenon.

Motor-evoked potentials in amyotrophic lateral sclerosis: potential implications in detecting subclinical UMN involvement in lower motor neuron phenotype

BackgroundIn amyotrophic lateral sclerosis (ALS), the involvement of lower motor neuron is well defined by electromyography, whereas a reliable marker of upper motor neuron (UMN) damage still lacks. Aim of the study was to estimate the role of transcranial magnetic stimulation (TMS)-induced motor-evoked potentials (MEPs) as marker of subclinical UMN involvement.MethodsClinical evidence of UMN damage was prospectively compared to MEPs in 176 ALS patients diagnosed between 2011 and 2014, and classified according to existing diagnostic criteria. Finally, we evaluated the appearance of clinical UMN signs and the level of diagnostic certainty in ALS after 1 year of follow-up.ResultsAt presentation, abnormal MEPs were found in 80% of patients with clinical evidence of UMN damage and in 72% of patients without clinical involvement of UMN. Among these latter, 61% showed appearance of UMN clinical signs after 1 year. Approximately 70% of patients with clinical lower motor neuron (LMN) phenotype showed MEP abnormalities, while they were considered not classifiable ALS according to Airlie house or Awaji criteria. Furthermore, abnormal MEPs in absence of clinical UMN signs at baseline were found in 80% of spinal ALS that after 1-year developed UMN signs at limbs, compared to 50% of bulbar ALS.ConclusionsTMS is a reliable marker of subclinical UMN damage particularly among LMN phenotype and ensure an early ALS diagnosis in ~ 70% of such cases.

A prospective harmonized multicenter DTI study of cerebral white matter degeneration in ALS.

To evaluate progressive white matter (WM) degeneration in amyotrophic lateral sclerosis (ALS). Sixty-six patients with ALS and 43 healthy controls were enrolled in a prospective, longitudinal, multicenter study in the Canadian ALS Neuroimaging Consortium (CALSNIC). Participants underwent a harmonized neuroimaging protocol across 4 centers that included diffusion tensor imaging (DTI) for assessment of WM integrity. Three visits were accompanied by clinical assessments of disability (ALS Functional Rating Scale-Revised [ALSFRS-R]) and upper motor neuron (UMN) function. Voxel-wise whole-brain and quantitative tract-wise DTI assessments were done at baseline and longitudinally. Correction for site variance incorporated data from healthy controls and from healthy volunteers who underwent the DTI protocol at each center. Patients with ALS had a mean progressive decline in fractional anisotropy (FA) of the corticospinal tract (CST) and frontal lobes. Tract-wise analysis revealed reduced FA in the CST, corticopontine/corticorubral tract, and corticostriatal tract. CST FA correlated with UMN function, and frontal lobe FA correlated with the ALSFRS-R score. A progressive decline in CST FA correlated with a decline in the ALSFRS-R score and worsening UMN signs. Patients with fast vs slow progression had a greater reduction in FA of the CST and upper frontal lobe. Progressive WM degeneration in ALS is most prominent in the CST and frontal lobes and, to a lesser degree, in the corticopontine/corticorubral tracts and corticostriatal pathways. With the use of a harmonized imaging protocol and incorporation of analytic methods to address site-related variances, this study is an important milestone toward developing DTI biomarkers for cerebral degeneration in ALS. NCT02405182.

Spreading in ALS: The relative impact of upper and lower motor neuron involvement.

ObjectiveTo investigate disease spread in amyotrophic lateral sclerosis (ALS), and determine the influence of lower (LMN) and upper motor neuron (UMN) involvement.MethodsWe assessed disease spread in ALS in 1376 consecutively studied patients, from five European centers, applying an agreed proforma to assess LMN and UMN signs. We defined the pattern of disease onset and progression from predominant UMN or lower motor neuron (LMN) dysfunction in bulbar, upper limbs, lower limbs, and thoracic regions Non‐linear regression analysis was applied to fit the data to a model that described the relation between two random variables, graphically represented by an inverse exponential curve. We analyzed the probability, rate of spread, and both combined (area under the curve).ResultsWe found that progression was more likely and quicker to or from the region of onset to close spinal regions. When the disease had a limb onset, bulbar motor neurons were more resistant. Furthermore, in the same time frame more patients progressed from bulbar to lower limbs than vice‐versa, whether predominantly UMN or LMN involvement. Patients with initial thoracic involvement had a higher probability for rapid change. The presence of predominant UMN signs was associated with a faster caudal progression.InterpretationContiguous progression was leading pattern, and predominant UMN involvement is important in shortening the time for cranial‐caudal spread. Our results can best be fitted to a model of independent LMN and UMN degeneration, with regional progression of LMN degeneration mostly by contiguity. UMN lesion causes an acceleration of rostral‐caudal LMN loss.

Nucleus Polposus Embolism Causing Anterior Spinal Artery Occlusion: A Rare but Possible Cause of Fibrocartilaginous Embolic Myelopathy.

Fibrocartilaginous embolic myelopathy (FCEM) is a rare cause of spinal cord infarction. It has been confirmed by autopsy in postmortem cases. Herein we describe a case of FCEM diagnosed based on clinical grounds. A 58-year-old man presented with acute onset of complete paraplegia with bladder and bowel involvement developing a few hours after a trivial trauma. There were no upper motor neuron signs. His magnetic resonance imaging (MRI) was suggestive of longitudinally extensive transverse myelitis from T5 to the conus. There was left paracentral disc protrusion at the T4-T5 level. However, no features of inflammatory, infectious, or autoimmune etiology were found on history, on examination, or in blood or cerebrospinal fluid analysis, and there was no contrast enhancement on MRI. A diagnosis of anterior spinal artery occlusion was made based on clinical examination with sparing of posterior column sensations in the lower limbs, predominant involvement of anterior half of the spinal cord on MRI, and accompanying new onset of back pain with rapid symptom progression to nadir as opposed to inflammatory etiology. Fibrocartilaginous embolism was suspected after ruling out all other causes of vascular compromise and presence of disc herniation at T4-T5. He was managed with rehabilitation and showed no signs of recovery. FCEM, though rare, should be kept in mind as a differential diagnosis of acute medical myelopathy when no other cause can be identified.

Editors' note: Peripheral synucleinopathy in a DJ1 patient with Parkinson disease, cataracts, and hearing loss

In their article, Narendra et al. reported the case of a 35-year-old man with novel compound heterozygous DJ1 mutations who presented with early-onset Parkinson disease (PD) and was found to have autonomic peripheral synucleinopathy and impaired olfaction. They proposed that the clinical triad of early-onset PD, cataracts, and sensorineural hearing loss seen in this patient may be specific for DJ1. In response, Drs. Namnah et al. referenced 2 other published cases that reported a similar association and report another patient of Iranian-Jewish ancestry with young-onset cataracts and PD with DJ1 mutations, suggesting that young-onset cataracts in PD should direct clinicians to DJ1 testing. Responding to this comment, Narendra et al. note that the patient reported by Namnah et al.—besides substantiating their conclusion—also had both lower and upper motor neuron signs—another atypical PD feature seen in some DJ1 patients. They also note that 2 of the reported patients with Iranian-Jewish ancestry shared a mutation with another reported family of Iranian-Jewish descent, indicating a founder effect in this population. This exchange highlights the enduring importance of meticulously characterized case reports in modern neurology to strengthen genotype-phenotype correlations, particularly in relatively rare genetic diseases. In their article, Narendra et al. reported the case of a 35-year-old man with novel compound heterozygous DJ1 mutations who presented with early-onset Parkinson disease (PD) and was found to have autonomic peripheral synucleinopathy and impaired olfaction. They proposed that the clinical triad of early-onset PD, cataracts, and sensorineural hearing loss seen in this patient may be specific for DJ1. In response, Drs. Namnah et al. referenced 2 other published cases that reported a similar association and report another patient of Iranian-Jewish ancestry with young-onset cataracts and PD with DJ1 mutations, suggesting that young-onset cataracts in PD should direct clinicians to DJ1 testing. Responding to this comment, Narendra et al. note that the patient reported by Namnah et al.—besides substantiating their conclusion—also had both lower and upper motor neuron signs—another atypical PD feature seen in some DJ1 patients. They also note that 2 of the reported patients with Iranian-Jewish ancestry shared a mutation with another reported family of Iranian-Jewish descent, indicating a founder effect in this population. This exchange highlights the enduring importance of meticulously characterized case reports in modern neurology to strengthen genotype-phenotype correlations, particularly in relatively rare genetic diseases.