1. Thoracic and Lumbar Spinal Mechanics Flashcards
Landmarks of the gravitational line (lateral)
- external auditory canal
- head of the humerus L3
- anterior 1/3 sacrum
- lateral malleolus
Spinal curves (lateral view)
- cervical lordosis
- thoracic kyphosis
- lumbar lordosis
- sacral kyphosis
characteristics of thoracic vertebra (T1-T12)
- body: medium sized, heart-shaped, w/ costal facets
- spinous process: long, slope postero-inferiorly
characteristics of lumbar vertebra (L1-L5)
- body: large, kidney-shaped
- spinous process: short, broad
rule of 3’s
refer to the location of spinous process in relation to the transverse process in the thoracic spine
rule of 3’s: T1-T3 (T12)
SP @ level of corresponding TP
rule of 3’s: T4-T6 (T11)
SP @ 1/2 segment below corresponding TP
rule of 3’s: T7-T9 (and T10)
SP @ level of TP 1 vertebrae below
orientation of superior facets: cervical region
BUM (backward, upward, medial)
orientation of superior facets: thoracic region
BUL (backward, upward, lateral)
orientation of superior facets: lumbar region
BM (backward, medial)
strong, broad fibrous band that covers and connects anterolateral aspects of the vertebral bodies and IV discs; limits extension
anterior longitudinal ligament
narrow, weaker band that runs with the vertebral canal along the posterior aspect of the vertebral bodies; resists hyperflexion; prevents posterior herniation of nucleus pulposus
posterior longitudinal ligament
connects the laminae of adjacent vertebra
ligamentum flava
connects adjoining spinous processes
interspinous ligaments
connects adjoining transverse processes
intertransverse ligaments
ligaments from L5 TP to iliac crest
iliolumbar ligament
[important] transversospinalis muscles of the spine
- semispinalis
- rotatores longi
- rotatores breves
- multifudus
extends the thoracic spine (bilaterally) and rotates thoracic spine to opposite side (unilaterally)
rotatores muscles (breves and longi)
extends spine (bilaterally) and flexes spine to the same side/rotates to opposite side (unilaterally)
multifudus m.
extends thoracic and cervical spines and head (bilaterally) and bends head, cervical and thoracic spines to the same side, rotates to the opposite side (unilaterally)
semispinalis muscles (capitis, cervicis, thoracis)
vertebral motion: flexion
S1 > vertical, C7 (40-90 degrees)
vertebral motion: extension
S1 > vertical, C7 (20-45 degrees)
vertebral motion: sidebending
S1 > vertical, C7 (15-30 degrees)
vertebral motion: rotation
center of head > acromion, ASIS (3-18 degrees)
consistent association of a motion along or about one axis w/ another motion about or along a second axis (prinicipal motion cannot occur without associated motion)
coupled motion
relationship of joint mechanics with surrounding structures to increase ROM
linkage
vertebral motion
movement of the anterior/superior surface of the vertebra
excessive motion (or restriction)
in reference to the vertebra above in a functional vertebral unit
vertebral unit
2 adjacent vertebra + associated IV disc
physiologic barrier
limit of active motion
anatomic barrier
limit of motion imposed by anatomic structure; limit of passive motion
elastic barrier
range between the physiologic and anatomic barrier of motion in which passive ligamentous stretching occurs before tissue disruption
restrictive barrier
functional limit within the anatomic range of motion; abnomrally diminishes the normal physiologic range
Why does spinal SD matter?
- restrictions of motion in the spine
- reduce efficiency
- impair flow of fluids
- alter nerve function
- creaste structural imbalance
Fryette: Type I Spinal Mechanics
In neutral range, sidebending and rotation are coupled in opposite directions. Rotation is towards the convexity of the spine. Tends to be a group of vertebra.
(Arrows point in opposite directions - sidebending and rotation are opposite)
Fryette: Type II Spinal Mechanics
In sufficient flexion or extension (non-neutral), sidebending and rotation are coupled in the same direction. Rotation is towards the concavity. Tends to be a single vertebra.
Mnemonic for Fryette Type One
TONGO
Mnemonic for Fryette Type Two
TTOSS
Name steps of SD nomenclature (Type 1)
- Locate vertebra or group.
- Indicate position (neutral).
- Indicate sidebending.
- Indicate rotation.
Name steps of SD nomenclature (Type 2)
- Locate the vertebra or group.
- Indicate position (flexion or extension).
- Indicate sidebending.
- Indicate rotation.
Fryette: Type III (“Third Principle”)
- Initiating movement of a vertebral segment in any plane of motion will modify the movement of that segment in other planes of motion.
- If motion is restricted in one direction, motion will also be restricted in other directions.
- If motion is improved in one direction, motion will improve in other directions.
What happens if you push anterior on the left transverse process?
vertebra rotates right
Name other ways to say “spine is rotated right.”
- posterior transverse process (PTP) on the right
- right PTP
- rotated right
- hard end-feel w/ rotation to the left
- hard end-feel on the right (when applying anterior force to right TP)
- restricted in rotation to the left
- will not rotate to the left
- lives in right rotation
- held to the right
Describe resistance and ease of motion with sidebending motion.
If sidebent to the right, resistance is encountered when translating to the right & ease of motion felt with translation to the left.
vertebral level: spine of scapula
T3 SP/T3 TP
vertebral level: inferior angle of scapula
SP T7/TP T8
vertebral level: iliac crest
level of L4
Scoliosis with convexity to the right
Dextro-scoliosis (frames the heart)
Scoliosis with convexity to the left
Levo-scoliosis (obscures the heart)
Scoliosis physical exam
- asymmetry of sacral base/perisapular area
- rib cage prominence
- leg length discrepancies
- Cobb angle
- Forward Bending test
- scoliomenter
Scoliosis management based on Cobb angle
- <25 degrees: conservative - monitor w/ frequent radiographs
- 25-45 degrees: non-operative - bracing
- > 50 degrees: surgical fusion - prevents progression
Possible complications with scoliosis
- respiratory compromise > 50 degrees
- cardiac compromise > 75 degrees
Radiculopathy
- pain with dermatomal distribution
- neurologic func may be impaired
- LE weakness
- diminished reflexes
- acute, may become chronic
- work-up: MRI
- test: SLR
SLR test
- Raise leg w/ knee extended
- Result: pain = (+) test
- pain from 15-30 degrees = lumbar disc etiology
Spinal stenosis
- bilateral lower limb pain
- neurogenic claudication
- neurological function may be impaired
- LE weakness
- diminished reflexes
- typically chronic
- work-up: MRI
- test: SLR
Cauda equina syndrome
- emergent
- impaired neurological function
- saddle anesthesia
- lower extremity weakness
- diminished reflexes
- urinary retention
- usually traumatic
- work-up: MRI
spina bifida oculta
failure of the neural tube to close w/o herniation
meningocele
failure of neural tube to close w/ protrusions of the meninges through defect
myelomeningocele
failure of neural tube to close w/ protrusion of meninges and SC through defect
Things to look for on lumbar x-rays (lateral & A/P)
- vertebral bodies
- lines
- intervertebral discs
Sacralization
one or both TPs of L5 are long and articulate w/ the sacrum (DJD)
Lumbarization
failure of S1 to fuse w/ rest of sacrum (uncommon)
Spina bifida
defect in closure of the lamina
What does this image show?
spondylosis
What does this image show?
spondylolysis
What does this image show?
spondylolesthesis (slipping of 1 vertebra on another)
