A study of anatomy and physiology of movement upper limb

The procedure of using the amphetamine tree branch to drink water supply is a complex wholeness which involves a huge amount of technology inter-transfer amid the mindset and the eventual skeletal vigour. at that place is initiation of the movement at the brain which is transmitted via specialized white fictitious character tracts to the hip flexors via the intermediate spinal anesthesia cord, involving a very complex mechanism at the cellular levelThe initiation of the process is at the labor cortex (Ms I) of the brain. The primary motor atomic takings 18a is located at the precentral vortex of the frontal lobe. The atomic number 18a controlling the doubt of the lower limbs lies towards the superior surface of the brain. inside this area lies the cell body of the primary neuron. These neurons are known as upper motor neurons (UMN).These UMNs receive modulating momentum from the inputs from the cerebellum and the extremist ganglia via the extrapyramidal pathways. These tracts modulate the gross movement initiated at the frontal cortex. In turn these areas are modulated by afferent signals from locomote spino cerebellar, and spino-thalamic pathways.The complex the signal initiated at the center of the cell body is transmitted electronically via the axon of the myelinated neuron via the personal way of salutatory conduction. The myelin sheath which surrounds the axon of jumpiness that involve fast transport, breaks at intermediate partings known as Nodes of Ranvier.The electrical impulse moves in a jumping manner at these nodes nerve transmission as a neural impulse, generated by the physical composition of a nerve consummation potential. alike all excitable tissue, nerves give a resting tissue layer potential that is the unlikeness of opinion of voltage across the membrane of the neuron. In neurons this value is 70 mV.This voltage difference is maintained by the Na/K pump on the membranes. This impulse generated at the axon hillo ck is transmitted via the depolarizing physical body which allows sodium ions ingress into cells via initiation of the Na channels. This entry of Na in one portion allows activation of other Na channels, causing depolarization of the adjacent region of the neuron. Subsequently repolarization occurs via the opening of K channels, which restores the membrane potential. Thus this process continues which allows the transmission of impulse.Many such nerves together descend as the descending cortico spinal tract in the pyramidal system, which travels through the midbrain into the spinal cord, decussating at the level of midbrain( 90% of the fibres decussating and forming the side(prenominal) spinothalamic tract) and again at the level of spinal cord ( the other 10%, forming the antecedent spinothalamic tract). It is the former which is responsible for the upper limb movements.The cortico-spinal tract travels in the anterior tusk cell of the spinal cord cashbox the lumbar level w pr esent they synapse with the spinal ventral root neuron (lower motor neuron). A single post-synaptic neuron receives signals from more neurons. At the axon terminal, the propagation of impulses leads to release of neurotransmitters, which are stored in specialized vesicles.The released Ach diffuses into the synaptic shot and binds with receptors on the post synaptic membrane to produce excitatory post synaptic potentials. This leads to generation and propagation of impulse in nerves which are destined to supply the neuro-muscular junction. At the neuro-muscular junction, Ach is released, which diffuses into the synovial cleft and binds to receptors in the motor end plate, and triggers a muscle action potential.The released Ach is destroyed by the acetylcholinestrase. At the level of the sarcolemma of the muscles, the muscle AP travels a vast T-tubules, opening Ca release channels in the sarcoplasmic reticulum. Ca binds to troponin-tropomysin complex, which releases the myosin hea ds, these then bind to the actin subjugate filaments, and draws them closer to the M line.Meanwhile bringing the Z disc closer. This leads to muscle fibre contraction. This is a self propagating sequence eventually principal to the contraction of ilio-psoas muscle, which causes the flexion of thigh on the pelvis. Each nerve fibre innervates many musle fibres ( about 150).This is the motor unit. The greater the number of motor units recruited by the nerve action potential, the greater the force of contraction of the muscles. In the spinal cord, nerve impulse travels along the brachial plexus to innervate the musculus deltoideus and supraspinatus (shoulder abductors), biceps, and brachialis( elbow flexion), flexor carpi ularis and flexor carpi radial-ply tireis (wrist flexors and stabilizers), long hitchhike flexors flexor digitorum superficialis anv flexor digitorum profundus (long feel joint flexors) leading to the person absorbing the glass and drinking water. In abridgment the impulse travels via brachial plexus ( C5-T1).From here the nerve impulses travel to shoulder elevators (supraspinatus, deltoid, trapezius, and latissimus dorsi)- prat cord ), elbow extensor (triceps and anconeus radial nerve) wrist extensor ( ECRL, ECRB radial nerve), finger flexors ( FDS, FDP median nerve and the ulnar nerve) and the intrinsics ulnar nerve and the median nerve).