Spinal Cord/Nerves Flashcards
How long is the spinal cord?
Roughly 16-18 Inches
What shape is the spinal cord?
Cylindrical
What are the two longitudinal depressions of the spinal cord?
Posterior and anterior median
What is the tapering end of the spinal cord called?
Conus Medullaris
How many pairs of spinal nerves are there
31 that contain both sensory and motor axons
What is the connective tissue found within the spinal cord?
Endoneurium- around an axon
Perineurium- around a fascicle
Epineurium- around the whole nerve
What are the four plexuses?
Cervical, brachial, lumbar, and sacral
Phrenic Nerve
Innervates diaphragm through thoracic cavity
Long Thoracic
Innervates serratus anterior
Medial Pectoral
Innervates pectoralis major AND minor
Lateral Pectoral
Innervates pectoralis major
Axillary
Innervates deltoid and teres minor
Radial
Innervates all muscles of posterior brachium, posterior antebrachium, and brachioradialis
Median
Innervates all muscles of antebrachium except the medial half of flexor digitorum profundus and flexor carpi ulnaris
Musculotanelis
Innervates all muscles in anterior brachium except brachioradialis
Ulnar
Innervates medial half of flexor digitorum profundus and flexor carpi ulnaris
Femoral
Innervates iliopsoas group, anterior thigh, and pectineus
Obturator
Innervates all muscles in medial thigh except pectineus
Superior Glutteal
Innervates gluteal group except gluteus maximus
Inferior gluteal
Innervates Gluteus Maximus
Sciatic Nerve
Innervates nothing (branches off into tibial nerve and common fibular nerve)
Tibial Nerve
Innervates all posterior thigh except biceps femoris short head and posterior leg
Common fibular
Innervates biceps femoris short head (branches into deep and superficial nerve)
Deep fibular
Innervates anterior leg
Superficial fibular
Innervates lateral leg
Pendundle nerve
Innervates perineum, external anal sphincter, and external urethral sphincter
What are the group of axons that project from the conus meduallris?
Cauda equina
What is the thin strand of pia mater that travels in the cauda equina that anchors the conus medularis to the coccyx
Filum Terminale
What enlargement accommodates extra nerves for upper appendages?
Cervical Enlargement
What enlargement accommodates extra nerves for lower appendages?
Lumbar englargement
What are the three meninges that cover the spinal cord?
Dura Mater, arachnoid mater, and pia mater (in order)
What space is between the dura mater and the bony vertebrae?
Epidural space
What are the two true spaces in the spinal cord
Epidural and subarachnoid
What is the potential space in the spinal cord?
Subdural Space
Which space is between the dura mater and the periosteum
Epidural Space
Which mater fuses with the connective layers that surround the spinal nerves
Dura Mater
Which mater adheres to the spinal cord?
Pia Mater
What are the triangular extensions that anchor the spinal cord to the dura mater
Denticulate Ligaments
What are the collections of spinal tracts in the white mater
Funiculi
What joins the two anterior funiculi
White commissure
What joins the two sides?
Grey commissure
What houses the somas of somatic motor neurons?
Anterior Horns
What contains the somas of automatic motor neurons from T12-L2?
Lateral Horns
What contains the axons for sensory and interneurons?
Posterior Horns
What is a continuation of the fourth ventricle?
Central Canal
What innervates the deeps muscles and skin of the back?
Posterior Rami
What innervates the anterior and lateral portions of the trunk and upper/lower appendages?
Anterior Ramus
What forms the intercostal nerves?
T1-11 anterior rami
What forms the subcostal nerve?
T12 anterior rami
Which is the only anterior rami involved in a plexus?
T1
What are the three components of a reflex?
- Receptor in PNS
- Communicates with the CNS
- Action occurs in a peripheral effector
