Spine- Thoracolumbar IV- Acute IDDs Flashcards
Which is more common, acute or persistent IDDs?
Persistent IDD
Which region of the spine is an IDD rarely found in?
Thoracic
Why are there greater consequences if there is an IDD in the thoracic spine?
Narrowest canal
What percentage of symptomatic disc herniations are in the thoracic region?
<1%
Where is an acute IDD most common?
Lumbar region
What percentage of IDDs are symptomatic?
1-3%
What percentage of LBP cases are caused by acute IDD?
<5%
What age group are acute IDDs mostly in?
30-50 year olds
What segments are 94% of the acute IDDs in the spine in?
L4-S1
What portion of the disc is the most common area for an acute IDD?
Posterolateral portion of the disc
Why is the posterolateral disc more susceptible to an acute IDD? (think fibers)
weaker, thinner, with MORE vertical and LESS oblique annular fibers
What is the acute IDD placement in the posterolateral disc just lateral to? Why does this matter?
The PLL, which means less reinforcement
What kinds of trauma can cause an acute IDD?
- axial compression
- forward bending or stooping with or without twisting/lifting
What is not happening with forward bending?
Lumbar spine NOT fully flexing
What does forward bending or stooping without or with twisting/lifting lead to?
- less circumferential disc compression
- MORE anterior segmental shearing force due to the pull of gravity, except less at L5,S1
Why is the less circumferential disc compression with forward bending or stooping trauma?
- unevenly distributed annular tension
- increased and asymmetrical stress on weaker and thinner POSTEROLATERAL annular and end plate fibers
- LESS fixated end plate
Where is there less anterior segmental force in bending/stooping without twisting?
at L5,S1
What structures are MORE commonly torn in acute IDD?
OUTER annular tearing and end plate avulsion
What structures are LESS commonly torn with acute IDD?
INNER annular tearing and NPH
What is the vascularity and innervation of the inner annulus?
Aneural and avascular
What is the vascularity and innervation of the outer annulus?
vascular and neural - heals better
What is the role of disc?
Shock absorption and load distribution
What happens to disc structures once damaged?
Immunoreactive - large AUTO immune inflammatory response occurs
What happens along with the large AUTO immune inflammatory response we see with acute IDD?
- Excessive osmotic pressure OR increased static fluid pressure in and around disc and spinal nerve
- Static fluid that consists of increased inflammatory chemicals that sensitizes spinal nerve and structures to pressure/tension
- radiculopathy/radicular S&S
- NO lymphatic veins in PNS or CNS so drainage is poor
- EXTENDED Inflammatory phase
What are typical posterolateral IDD symptoms?
- Dull/achy spinal pain
- Radiculopathy
- Referred pain into glutes and groin
Why is the pain with posterolateral IDD dull and achy?
- annulus highly innervated so very painful
- significantly MORE swelling than cervical disc due to higher number of GAGs
Why is there radiculopathy along with acute posterolateral IDD?
- possible segmental paresthesias within 24hours into distal extremity
- worse situation
> presence of radiculopathy
> presence of coldness indicating greater circulatory compromise
When is there typically reduced pain with typical posterolateral IDD?
reduced pain when unloaded
- lying and standing/walking
When is there typically increased pain with posterolateral IDD?
Increased LBP and paresthesias
- FB/sitting/lifting
- coughing/sneezing (increased pressure in the trunk since it is a forceful activity)