Flashcards in Lumbar disc Herniation Deck (21):
What is the most common level involved ?
L5/S1 most common
What is the peak age of incidence?
4th and 5th decades
What percentage become symptomatic?
what is the male:female ratio?
3male to 1 female
Describe the pathoantomy?
RECURRENT TORSIONAL STRAIN-> TEARS OF OUTER ANNULUS which leads to HERNIATION of the NUCLEUS PULPOSIS
What is the prognosis of lumbar disc herniations?
90% of patients will have improvements of symptoms at 3 months with NON-OP
SIZE of herniation DECREASES WITH TIME
Which type of discs show the greatest degree of spontaneous reabsorption?
What is the mechanism of reasbsorportion?
What is the disc composed of?
ANNULUS FIBROSIS- outside
of TYPE 1 COLLAGEN, h20 and proteoglycans
characterised by EXTENSIBILITY + TENSILE STRENGTH- high collagen low proteoglycan
of TYPE 2 COLLAGEN, h20, proteglycans
characterised by COMPRESSIBILTY- low collagen, high proteoglycan ( pg inexact w h20 and resist compression)
Describe the nerve root anatomy?
there are 2 key differences between the cervical and lumbar spine with respect to pathology and level
1) PEDICLE/ NERVE ROOT MISMATCH
Cervical spine C6 n root travels under C5 pedicle ( mismatch)
lumbar spine L5 n root travels under L5 ( match)
extra C8 n root ( no C8 pedicle) allows transition
2) HORIZONTAL (Cervical) vs VERTICAL (Lumbar) anatomy of nerve root
because vertical anatomy of lumbar nerve root - a paracentral and foramina disc will affect different nerve roots- i.e.far lateral disc at L4/5 will effect L4 n root cf paracentral L4/5 will effect L5 n root
because of horizontal anatomy of CERVICAL n root a central of foramina disc will effect the SAME n ROOT
Can you describe the LOCATION classification of disc prolapse?
CENTRAL - assoc w back pain only
may pc CAUDA EQUINA- surgical ER
most common 90-95%
PLL is weakest here
affects transversing/descending lower root-
at L4/5 affects L5
FORAMINAL ( FAR LATERAL)
less common 5-10%
affects exiting/UPPER n root -
at L4/5 affects L4
AXILLARY- can effect both exiting and descending nerve roots
Can you describe the ANATOMICAL classification of disc prolapse?
PROTRUSION- Eccentric bulging with intact
EXTRUSION- Disc material HERNIATES thru ANNULUS but remains continuous with disc space
SEQUESTERED FRAGMENTS (free)
Disc material herniates thru ANNULUS and is no longer continuous with disc space
What do patients present with?
AXIAL BACK PAIN- discogenic/mechanical in nature
RADICULAR PAIN- buttock/leg pain
often worse with SITTING,improves with standing
symptoms worsened by coughing,valsalva, sneezing
CAUDA EQUINA SYNDROME -present 1-10%
bilateral leg pain
What do you see on examination?
ankle dorsilfexion L4/5
EHL weakness L5
Hip abduction L5
Foot plantiflexion S1
Straight leg raise - tension side for L5/s1 n root
-> pain and parasthesia in leg at 30-70 degrees of hip flexion
gait- trendelenburg gait- due to glut medius weakness innervated by L5
What imaging can be used ?
xray- loss of lordosis
loss of disc height
lumbar spondylosis - degenerative change
MRI wout gadolium
mode of choice to identify lumbar/cervical disc herniations
high sensitivity and specificity
helpful preop planning
high rate of abnormal findings on MRI in Normal pt
what are the indications to obtaining an MRI scan?
Pain lasting for > 1 month and NOT RESPONDING to non-operative management
red flags= INFECTION
IV DRUG USER
CAUDA EQUINA syndrome
What are the tx options?
Non operative- rest, physical therapy and anti-inflammatory medications
1st line of tx for most patients with disc herniation- 90% improvement without surgery
- Bedrest then increased activity- extension exercises, pilates
medication- nsaids, muscle relaxants, oral steriod taper
outcome- similar results between operative and non operative at 4 years
What other non operative tx are there?
Selective nerve root corticosteriod injections
1st line of tx if therapy and medications fail
epidural/selective nerve block
outcome-> long lasting improvement in 50%
results best in pt with EXTRUDED discs as opposed to contained discs
What are the surgical options and their indications?
LAMINOTOMY and DISCECTOMY ( MICRODISCECTOMY)
indications- PERSISTENT DISABLING PAIN lasting more than 6/52 failed non op mx
PROGRESSIVE and SIGNIFICANT WEAKNESS
CAUDA EQUINA SYNDROME
What are the outcomes of surgery cf nonop?
Improvement in pain and function
70% improvement in pain
neurological recovery less predictable
50% motor /sensory recovery
25% reflex recovery