Search results
Results from the WOW.Com Content Network
The lateral corticospinal tract (also called the crossed pyramidal tract or lateral cerebrospinal fasciculus) is the largest part of the corticospinal tract. It extends throughout the entire length of the spinal cord , and on transverse section appears as an oval area in front of the posterior column and medial to the posterior spinocerebellar ...
UMNs are motor neurons that project from the cortex down to the brainstem or spinal cord. [18] LMNs originate in the anterior horns of the spinal cord and synapse on peripheral muscles. [18] Both motor neurons are necessary for the strong contraction of a muscle, but damage to an UMN can be distinguished from damage to a LMN by physical exam. [19]
Subacute combined degeneration of spinal cord; Diagram of the principal fasciculi of the spinal cord. (In subacute combined degeneration of spinal cord, the "combined" refers to the fact that the dorsal columns and lateral corticospinal tracts are both affected, in contrast to tabes dorsalis which is selective for the dorsal columns.)
Distal muscular dystrophy, also called distal myopathy, is essentially any muscle disease that preferentially affects the hands and/or feet, a much less common pattern than proximal muscle weakness.
The corticospinal tract is a white matter motor pathway starting at the cerebral cortex that terminates on lower motor neurons and interneurons in the spinal cord, controlling movements of the limbs and trunk. [1] There are more than one million neurons in the corticospinal tract, and they become myelinated usually in the first two years of life.
Of all the circuits, the motor circuit is the most studied due its importance to motor disorders. The direct pathway of the motor circuit is one in which projections from the cortex travel to the putamen directly to the internal segment of the globus pallidus (GPi also known as GP-Medial) or the substantia nigra, pars reticulata (SNr) and are then directed toward the ventral anterior nucleus ...
A lower motor neuron lesion is a lesion which affects nerve fibers traveling from the lower motor neuron(s) in the anterior horn/anterior grey column of the spinal cord, or in the motor nuclei of the cranial nerves, to the relevant muscle(s).
Hyperkinetic movement disorders refer to dyskinesia, or excessive, often repetitive, involuntary movements that intrude upon the normal flow of motor activity. Hypokinetic movement disorders fall into one of four subcategories: akinesia (lack of movement), hypokinesia (reduced amplitude of movements), bradykinesia (slow movement), and rigidity ...