lig muscle facet neuro Flashcards
What are the ligaments of the lumbar spine?
- ALL
- PLL
- LF
- IS
- SS
- iliolumbar
- frominal
What are the attachments of the ALL?
- starts at the atlas and runs to the sacrum
- narrow in the cervical spine
- margins of vertebral body
- skips over endplate
- disc
What is the function of the ALL?
- resist extension
2. resist shear
What are the attachments of the PLL?
- runs from axis to the sacrom
- narrow in the lumbar spine
- disc
- endplate
- not the body to allow for the nutrient artery to enter the body of the vertebrae
What are the attachments of the LF?
- superiorly it attaches to the inferior aspect of the anterior lamina and posterior pedicle
- divides into medial and lateral portions
a. medial- runs to the posterior aspect of the lamina below
b. lateral- runs in front of the facet to create the anterior facet capsule - actually composed of 7 smaller ligaments
Neurologically what is unique about the anterior facet capsule?
the anterior capsule is formed by the ligament flavum and it does not have any type IV mechanoreceptors
What happens to the LF in presence of pathology?
it has a tendency to thicken and ossify when the segment is hypermobile
What happens to the LF in presence of pathology?
its elastric properties allow it to contract and prevent capsular entrapment like the psoas, genu articularis, or other muscle attached to joint capsules
How are the interspinous ligaments oriented?
Obliquely to allow for flexion of the lumbar spine
What are the attachments of the supraspinous ligaments
a. runs from ligamentum nuchae down to about L4, sometimes to L5
b. blends with the IS ligaments
What are the attachments of the iliolumbar ligaments?
- TPs of L4 and L5 to the illac crest
2. blends with the quadratus lumborum muscle
What are the attachments of the thoracolumbar fascia?
- SP of the t and l spine
- lower ribs near the angles
- muscle of the abdomen
- wraps around quadratus lumborum, erector spinae and multifidus
- illiolumbar ligaments
- down to the facets in the lumbar spine
- illiac crest
- SI joints
- glut max
- latissimus
How are the fibers of the interspinous ligaments oriented?
- they run obliquely superior and posterior
2. this orientation allows for flexion of the spine, if they were vertically oriented thye would prevent flexion
What are the attachments of the supraspinous ligament?
- runs across the tops of the spinous processes
- blends with the intraspinous ligaments
- runs from ligamenttume nuchae to L4, rarely to L5 and never to S1
What muscle does the ioliolumbar ligament most closely relate?
lumbar iolocostalis- it is thought the 5th fascicile of the muscle turns into the iololumbar ligament
What are the attachments of the iliolumbar ligaments?
- originate from trasverse processes of L5 and sometimes L4
2. insert anterior margin of the illiac crest
What are the functions of the iliolumbar ligaments?
- anterior band limits flexion
- posterior band limits SB
- bilaterally they work to limit both flexion and extension
- contribute ab out 35% to the control of rotation
- limits sacral flexion
- in the presence of L5 DDD it facilitate segmental stability
Tenderness of the iliolumbar ligament is contributed to what segment?
palpation of iliolumbars is not possible therefore tenderness is most likely a symptoms of upper lumbar issues
What muscle of the lumbar spine does not attach to the lumbar spine?
iliocostalis thoacic which attaches to the TP and ribs of the lower thoracic spine and inserts on the ilium and sacrum
What are the anterolateral muscle of the lumbar spine
- psoas
2. psoas minor
What are the lateral muscles of the lumbar spine?
- quadratus lumborum
2. intertransversarii lateralis
What are the posterior muscles of the lumbar spine?
- Superficial layer
a. erector spinae group of iliocostalis lumbar and thoracis and longissimus lumoborum and thoracic - Deep layers
a. interspinalis
b. intertransversarii medialis
c. mulitifidus
What are the functions of the multifidi?
- slight rotation, but a very small vector
- eccentric stabilizer of rotation
- oppose the flexion effect of the abdominal obliques
- accentuate lordosis
What are the attachments of the lumbar longissimus
- Five fascilies starting at the accessory process and medial TP
- posterior superior iliac spine
What are the attachments of the lumbar ioliocostalis?
arise from the TP fo L1-4, thoracolumbar fascia
attach to the iliac crest
What are the attachments of the thoracic longissimus?
- arise in pairs from the TPs and ribs of T1/2 to T12
2. insert on spinous process of the lumbar spine and sacrum
What are the attachments of the thoracic iliocostalis?
- arise from lower seven or eight ribs
2. insert of the ilium and sacrum
What are the margins of the capsule?
- dosal capsule attaches about 2mm from the edge of the articular cartilage
- superior and inferior margins attach even further away
- ligamentum flavum makes up the anterior capsule
What structural components of the facet capsuele put it at risk for acute locking?
Meniscoids
What are the different types of meniscoids?
- Wedge shaped rim of the capsule
- dampening fat pads at the superior and inferior poles
- fibroadipose type that is a fold in the synovium
What are the typical transverse plane lumbar facet joint shapes?
they are either “C” or “J” shaped
How are the facets of the lumbar spine oriented?
- in the upper lumbar spine that have a greater sagittal orientation
- L5 typically has a greater transverse orientation to resist shearing
What is facet tropism and how prevalent is it in the lumbar spine?
- asymmetrical orientation of the facets
- as much as 20% in lumbar spine
- as much as 30% in the TL junciton
What are the nerve root sleeve and how are they oriented?
- extensions of the dura that guide the spinal nerve to the foramen
- they arise behind there conresponding vertebral body in the upper lumbar spine
- as you progress down the lumbar spine the roots sleeves branch off higher and by the time you reach L5 it branches off behind the body of L4
What does the anterior primary rami do?
form the plexus of nerves going to the extremities
What path does the anterior primary rami follow as it exits the foramen?
- pierces the the ventral leaf of the intertransverse ligament
- travels into the psoas muscle
What does the posterior primary rami do?
- The L 1-4 dorsal rami tend to form three branches, medial, lateral, and inter- mediate, which are distributed, respectively, to multifidus, iliocostalis, and longissimus. The intertransversarii mediales are innervated by a branch of the dorsal ramus near the origin of the medial branch.
- The L 5 dorsal ramus is much longer than the others and forms only a medial and anintermediate branch.
- Each lumbar medial branch innervates two adjacent zygapophysial joints and ramifies in multifidus, supplying only those fascicles which arise from the spinous process with the same segmental number as the nerve.
- L1-3 lateral branches form cutaneous branch that run down the back traveling parallel to the subcostal nerve, L4 and L5 are entirely muscular
- additionally it can ascend and descend several segments
What is the path of the posterior primary rami
- make a posterior right turn to pass around the articular pillar
- divides into three branches
a. posterior
b. intermediate
c. lateral - Upper three lumbar segements have cutaneous branches supplying posterior lumbar, iliac crest, sacrum and greater trochanter
What is the recurrent nerve?
- a small branch of the APR that turns around and runs back into the foremen
- it carries sensory information from the somatic structures in and around the disc
- it carries autonomic information to its target organs
What somatic structures does the recurrent nerve innervate?
- PLL
- ALL
- anterior dura mater
- outer 50% of the annulus
- it travels up at least one segment and down as many and two segments
- it crosses over to the contralateral side
What role does the recurrent nerve play in the sympathetic nervous system?
the sympathetic fibers are post ganglionic and will influence vascular tone in this region
What is sympathetic pain?
- There really isn’t any such thing because the sympathetic nervous system is efferent in nature and does not transmit any information to the brain
- instead it can effect vascular tone creating ishemia
What three anomalies can occur at the nerve roots?
- type I: two pairs in a single dural sleeve
- type II: number of nerve roots in a foramen varies
- type III: Extra dural where one root sleeve will join another or send an anastomosis branch
What clinical finding are present in a nerve root pathology?
- sensory
- motor
- DTR
- Changes are noted in both the anterior and posterior primary rami
What are alternative explanations for motor changes in the absence of true nerve root pathology?
- trigger points
2. pain related inhibition or facilitation
How are the facets of the lumbar spine innervated?
- Posterior primary rami
2. each facet con send afferent information via the rami to segments above and below because of the multisegmental PPR
What mechanoreceptores sense motion?
- Type I- respond to inner and outer ROM
- type II- respond to inner and mid ROM
- type III- respond to exessive motion via modulation of the DH
- type IV- respond to excessive motion
What does the brain have difficulty isolating the location of pain in the spine?
- it only has segmental reference for pain
- Medial branch of the PPR travels up and down multiple segments
- the recurrent nerve travels bilaterally and up and down multiple segments
What are the different subsystems of the autonomic nervous system?
- sympathetic nervous system
2. parasympathetic nervous system
Where do you find the preganglionic nerve fibers for the sympathetic nervous system?
T1-L2
Where are the preganglionic nerve fibers of the PNS located?
- brainstem
2. middle three segments of the sacrum
How do the PNS and SNS work together?
- SNS responsible for responding to environmental demands
2. PNS responsible for maintaining homeostasis
What are the layers of the dura mater?
- outer- loosely arranged fibroelastic collagen
- middle- fibrous protien
- inner- cellular layer
How is the dura anochored to surrounding structures?
- attaches to the foramen by the dentate ligaments
- fibrous slips to the PLL ties it into the foramen magnum, C2 and C3
- dural ligaments tie it to the PLL as it descends down the vertebral column
- Rectus capitus posterior minor ties into the posterior part to prevent entrapment with cervical extension
- filum terminalis descends posterior to the coccyx and blends into the periosteum
What is the epidural space and what do you find there?
- space between the dura and the periosteum
2. filled with connective tissue, fat and venous plexus
What is the arachoid mater?
- delicate highly vasulcuar space filled with CSF
2. follows the spinal nerves to the vertebral cannal
What is the pia mater?
vascular membrane and connective tissue surrounding the spinal cord
How mobile is the spinal cord?
- it can stretch up to 10% of its length before it firmly resists addition stretching
- in the cervical spine is has an accordion shape that allow for greater motion
- additionally it demonstrates viscoelastic properties because of its high fluid content
