Back Neurology Flashcards
spinal meninges description
three layers that cover SC
dura mater
arachnoid mater
pia mater
anatomy of spinal dura mater
epidural space dura-arachnoid interface spinal dural sac dural root shealth filum terminale externum
epidural space
occupied by internal vertebral venous plexus and epidural fat
dura-arachnoid interface
potential space, no natural space exists here, often erroneously referred to as subdural space
spinal dural sac
long tube-shaped sheath surrounding SC lining the vertebral canal
dural root sheath
lateral tapering extension of spinal dura mater that surround anterior and posterior roots
filum terminale externum
dural part of terminal filum
continuation of filum terminale internum
travels through sacral hiatus and inserts on coccyx
anatomy of spinal arachnoid mater
subarachnoid space
arachnoid trabeculae
lumbar cistern
subarachnoid space
CSF filled space between arachnoid and pia mater
arachnoid trabeculae
delicate strands of connective tissue that span the subarachnoid space joining arachnoid and pia mater
lumbar cistern
enlargement of subarachnoid space inferior to the conus medullaris containing the cauda equina
anatomy of spinal pia mater
denticulate L.
filum terminale internum
denticulate L.
lateral extension of fibrous pia mater at regular intervals between spinal roots to attach to dural sac
suspends spinal cord in dural sac
filum terminale internum
continuation of pia mater inferior to the conus medullaris, eventually picks up layer of dura mater inferior to dural sac and becomes filum terminale externum
cervical enlargement
swelling of SC from C4-T1
corresponds with brachial plexus and UE
lumbosacral enlargement
swelling of SC from T11-S1
corresponds with lumbar and sacral plexuses and LE
spinal cord segments
part of SC that produces spinal rootlets that converge to form spinal roots that converge to form a spinal N. that then branches into spinal rami
anterior root
central projections from neuronal cell bodies in the anterior horn of SC, converge with posterior root to form spinal N. at each segment
posterior root
central projections from neuronal cell bodies in the spinal ganglion, converge with anterior root to form spinal N. at each segment
anterior rootlets
small fibers originating from SC that converge to form single anterior root at each SC segment
posterior rootlets
small fibers originating from SC that converge to form single posterior root at each SC segment
spinal ganglion
collection of sensory nerve cell bodies associated with posterior root
spinal Ns. description
mixed general sensory and somatic motor 31 pairs (8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal) VERY SHORT union of anterior and posterior roots that quickly branches into anterior and posterior rami
cervical spinal Ns. special notes
C1 spinal nerve exist vertebral column above C1, C2 spinal nerve exits the vertebral column between C1 and C2
anterior rami of cervical spinal Ns.
cervical plexus (C1-4) brachial plexus (C5-T1) recurrent meningeal branches (sensory and sympathetic fibers to the dura mater)
posterior rami of cervical spinal Ns.
suboccipital N. (C1, innervates suboccipital musculature, travels through occipital triangle)
great occipital N. (C2)
least occipital N. (C3)
C4-8 (cutaneous and muscular innervation, medial and lateral branches)
medial branches of C4-8 posterior rami
muscular branches innervates transversospinalis Ms.
articular branches innervate zygapophyseal joints
cutaneous branches to skin of dermatome
lateral branches of C4-8 posterior rami
muscular branches innervates erector spinae and splenius Ms.
cutaneous branches to skin of dermatome
anterior rami of thoracic spinal Ns.
atypical intercostal N. (T1,2,7-11)
typical intercostal N. (T3-6)
subcostal N. (T12)
recurrent meningeal branches (sensory and sympathetic fibers to the dura mater)
atypical intercostal N.
T1-2 send branches to brachial plexus
T7-11 become thoracoabdominal N.
posterior rami of thoracic spinal Ns.
medial and lateral branches
medial branches of posterior rami of thoracic spinal Ns.
muscular branch innervates transversospinalis Ms. and longissimus thoracis M.
articular branch innervates zygapophyseal joint
cutaneous branch innervates skin of dermatome
lateral branches of posterior rami of thoracic spinal Ns.
muscular branch innervates erector spinae Ms.
cutaneous branch innervates skin of dermatome
anterior rami of lumbar spinal Ns.
lumbar plexus (L1-4) lumbosacral trunk (L4,5) recurrent meningeal branches (sensory and sympathetic fibers to dura mater)
posterior rami of lumbar spinal Ns.
medial and lateral branches
medial branches of posterior rami of lumbar spinal Ns.
muscular branch innervates transversospinalis Ms., interspinalis Ms., and intertransversarii Ms.
articular branch innervates zygapophyseal joint
cutaneous branch innervates skin of dermatome
lateral branches of posterior rami of lumbar spinal Ns.
muscular branch innervates erector spinae Ms.
cutaneous branch innervates skin of dermatome
superior cluneal N. (L1-3)
anterior rami of sacral spinal Ns.
sacral plexus (L4-S4) coccygeal plexus (S4,5) recurrent meningeal branches (sensory and sympathetic fibers to the dura mater)
conus medullaris
distal cone shaped terminal end of SC typically begins tapering off at T12 and ends at L2
cauda equina
bundle of anterior and posterior roots from the lumbosacral enlargement and conus medullaris
spinal cord injury (SCI)
complete transection results in loss of sensation and motor function below the lesion
SCI C1-3
no function below the head, respirator necessary for life
SCI C4-5
no function of limbs, respiration capable
SCI C6-8
loss of hand and variable upper limb function, may be able to propel a wheelchair
SCI T1-9
paralysis of both lower limbs
SCI T10-L1
some thigh muscle function, may allow walking with long leg braces
SCI L2-3
most lower limb functions present, may be able to walk with short leg braces
five categories of structures innervated by recurrent meningeal N. (anterior rami) and posterior rami
fibroskeletal structures (periosteum and ligaments), meninges, synovial joints, intrinsic back Ms.
most common causes of back pain
muscular, joint, and fibroskeletal pain
muscular pain
result of spasm producing ischemia
joint pain
result of osteoarthritis or disease arthritis
fibroskeletal pain
result of Fx’s and dislocation of ligamentous structures
