Cauda Equina Compression and Thoracolumbar Trauma Flashcards
The ________ is the terminal end of the spinal cord, which typically occurs at the ________ vertebral level in an adult.
The continuation of nerves fibers beyond the spinal cord is known as the ________.
conus medullaris, L1, cauda equina
List the motor, sensory and PNS Innervation of the Cauda Equina
Motor: legs, lower legs, foot and ankle, sphincters
Sensory: legs, lower legs, foot and ankle, saddle, peri-anal
PNS: bladder and distant bowel
“Keeps you Mobile and Continent”
Explain the PNS Innervation of the cauda equina (incl nerve roots)
S2-4
- Synapse for the bladder wall
- Stimulates contraction of the muscle fibres
- Relaxes the sphincters
- Controlled Micturition
How does cauda equina present?
What is the impliction of this presentation?
Combination of neuromuscular and urogenital symptoms but no such thing as a common presentation
Requires a high index of suspicion and an examination of patient
Pathophysiology of Cauda Equina Syndrome - Why is the CE at an increased risk?
Compression of the cauda equina nerve roots from ANY cause
Nerve roots at this level have a poorly developed epineurium, with relative hypovascularity in the proximal 1/3 ➞ Increased permeability from CSF support nutritional supply
This increased permiability = Increased susceptibility to pressure and more likely to become oedematous
Give the Aetiology of Cauda Equina syndrome
Frequency: CES is uncommon, both atraumatically as well as traumatically.
Mortality/Morbidity: CES is not fatal. Morbidity is variable, depending on the etiology of the syndrome.
Race: No predilection exists on the basis of race.
Sex: No predilection exists on the basis of sex.
Age: Traumatic CES is not age specific. Atraumatic CES occurs primarily in adults
Give 4 causes of CES
- Ruptured Disc (most common)
- Stenosis (narrowing)
- Tumour
- Infection
- Fracture / Trauma
- Narrowing
- Others (congenital, vascular)
What is seen on the image below
Disc Prolapse - common cause of CES
Give 4 differential diagnosis for CES
- Back Pain, Mechanical
- Guillain-Barré Syndrome
- Lumbar (Intervertebral) Disc Disorders
- Neoplasms
- Spinal Cord Infections
- Spinal Cord Injuries
Diagnosis of of CES requires neuromuscular and urogenital symptoms, list 4 of these
- lower limb weakness
- sensory changes/numbness in lower limbs or saddle area
- back pain (with or without sciatic type pains)
- dysfunction of bladder, bowel or sexual nature
- bilateral symptoms
- areflexia
Revise slide
What examination must we do if CES is suspected?
Rectal exam (PR) ➞ assess tone, peri-anal sensation, “squeeze”, etc…
Why is it important to know whether a patient has urinary retention in CES?
The outcome is very different
CES-R(etention) has a poorer outcome than CES-I(ncomplete)
How may we assess alteration in bladder function in a patient suspected of CES
May be assessed empirically by obtaining urine via catheterization.
A significant volume with little or no urge to void, or as a post-void residual, may indicate bladder dysfunction
Give 4 symptoms of CES
- Back pain, especially of new onset
- Weakness in the legs, unable to rise from a chair
- Unable to walk
- Numbness
- Loss of sexual sensation
What is the 3 column theory of spinal stability in trauma
The vertebral column is divided into 3 vertical parallel columns
Instability occurs when injuries affect 2 contiguous columns (eg. anterior and middle or middle posterior column).
Obviously a 3 column injury is also unstable
Explain the patho of a compression (wedge) fracture + what is seen on an X-ray
Anterior column fails
Middle column intact – posterior part of the vertebral body is intact
Anterior wedging on the lateral view (lateral wedging on the AP view if lateral flexion)
Explain the patho of a burst fracture + what is seen on an X-ray
Involves anterior and middle column by axial compression force
AP view
- vertical fracture of the lamina
- widening of the inter-pedicular distance
- disruption/splaying of the facet joints
Lateral view
- majority involve the superior end plate
- decreased height posterior part of vertebral body
- fragments often retropulsed into spinal canal
Explain the patho of a Chance fracture + what is seen on an X-ray
Failure of the posterior and middle columns by flexion ➞ anterior column acts as a hinge and may also fail
X-Ray findings
- horizontal split of the transverse processes and pedicles
- horizontal fracture of the spinous process
- Increased inter-spinous distance
Axial CT may not provide additional information as the horizontal split is in the axial plane
What sign is seen on an AP view of a chance fracture
How do fracture dislocations usually occur and what deficit is often present?
Often high energy injury, seen in polytrauma cases
Often severe neurological deficit
Desribe ‘spinal protection’ in Pre-Hospital Care
- If the neck is not in neutral position, an attempt should be made
- Active if patient is awake and co-operative, Passive if unconscious or unable to co-operate
- If there is pain, neurological deterioration or resistance to movement the procedure should be abandoned and the neck splinted in the current position
