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.

Acute spinal cord infarction syndrome unusually mimicking Transverse myelitis: A case report

Anterior Spinal Cord Infarction (ASCI) syndrome typically results from ischemia that affects the anterior spinal artery territory characterized by history of sudden onset flaccid paraplegia or quadriplegia depending on the level of the lesion. We describe a 57-years-old woman with sudden onset flaccid weakness of the lower limbs and numbness of the feet of two days duration, preceded by a day history of fever and several episodes of vomiting. Examination initially revealed bilateral hypotonia, hyporeflexia and dense paraplegia, with preservation of dorsal column sensations (fine touch/2-point discrimination, position and vibration sensation). Twenty-four hours thereafter a repeat examination showed hyper-reflexia and extensor plantar response with spastic paraplegia. Thoracic spine Magnetic Resonance Imaging (MRI) revealed thinning of the spinal cord extending from T1 to T9 levels with associated widening of the thecal sac suggestive of anterior spinal cord infarction with no other signal changes seen within the substance.

GBS with Bilateral plantar extensor – A case report

GBS is an immune mediated polyradiculoneuropathy classically characterized by acute symmetrical ascending lower motor type weakness and areflexia. But sometimes, in axonal variants of GBS, reflexes are preserved or exaggerated. We report a case of GBS with bilateral extensor plantar response during the course of the disease. A 36- year-old male presented with acute quadriplegia with asymmetrical muscle weakness and extensor plantar response. Sensory, bowel and bladder function was intact. He was treated with intravenous methylprednisolone daily for 5 days without improvement. NCS revealed AIDP and AMAN variants of GBS. So, in any patient presenting with acute quadriplegia with extensor plantar response, GBS should be considered as differential diagnosis. Bangladesh Journal of Neuroscience 2015; Vol. 31 (1): 42-44

FRIEDREICH ATAXIA – A CASE REPORT

Friedreich ataxia is an autosomal recessive disorder, due to expansion of trinucleotide repeat in Frataxin gene which presents with ataxic gait, absent tendon reflexes, extensor plantar response and positive Romberg test. We present a child who came with complaints of progressive ataxia of gait since the age of 10 years and was diagnosed to have Friedreich ataxia. They have associated cardiomyopathy and endocrine abnormality like diabetes and hypothyroidism.