Week 9 Spinal Stenosis Ddx Flashcards
Diagnosis requires which 3 factors?
- Characteristic signs/symptoms
- Radiographic (MRI or CT) evidence of lumbar spinal stenosis
- Exclusion of other causes of back and leg pain
Ddx for patients with low back and leg pain
Neuropathic:
- Nerve root: disc herniation, SOL (tumor, cyst, hematoma), osteophyte, compression fracture, spinal infection
- Peripheral neuropathy: piriformis syndrome, diabetes, herpes zoster, compartment syndrome, peroneal nerve compression
Referred:
- facets, deranged disc, MFTP, trochanteric bursitis, hip OA
- PAD, medial tibial stress syndrome, stress fracture of tibia or fibula, muscle strain
At what age is spinal stenosis at the top of the ddx for neuropathic leg pain?
> 60
Stenosis occurs in
__% of patients ___ -___ y.o. with leg pain
____% of patients >___ y.o. with leg pain
25%, 60-70
64%, >70
What are other ddx for patients over 60 with neuropathic pain? (A list and B list)
A list
- IVF encroachment (osteophyte secondary to DJD)
- SOL (cancerous tumor, less likely cyst)
B list
- radicular: degenerative spondylolisthesis, structural instability, spinal infection
- peripheral: diabetic, other peripheral neuropathy, piriformis syndrome
What are causes of IVF encroachment?
Spur/osteophyte
IVF stenosis
What are signs and symptoms of IVF encroachment? (4)
- no neurogenic claudication or CES symptoms
- often unilateral, sometimes a single dermatome
- positive kemp’s with pain into leg (suggest IVF is compromised)
- may not be as sensitive to pure flexion or extension loads
How do you ddx spinal stenosis from spur/osteophyte?
Advanced imaging
Tumor (especially malignant) are more likely in patients ___
> 50
What are signs/symptoms of tumor
- neurological deficits or cord signs (long track) may be present
- sometimes leg pain is accompanied by little or no back pain
- spinal percussion may be very sensitive
- may have classic red flags
- positive lab and imaging tests
What should you be concerned about in a patient >50 with leg pain and no back pain
Tumor
What are red fags for tumor
- prior history of cancer
- unexplained weight loss
- increase pain when lying supine
- unremitting pain affected by spinal positioning
What are positive ab findings for tumors?
- anemia
- increased ESR/CRP
- increase ALP (metastatic prostate cancer, osteoblastic cancer)
- proteins (on blood chem panel, multiple myeloma)
- hypercalcemia (osteolytic like metastatic breast cancer)
Spinal infections are very rare in the (long bones/spine?) and occur more in the (long bones/spine?)
Very rare in spine
More in long bones and extremities
What age are spinal infections most common?
> 50
What are some signs/symptoms of spinal infection? (6)
- rapid or but usually slow indolent course
- prior history of infection (kidney/bladder infection) or immune compromised patient
- may run fever (65% of cases)
- usually very sensitive to spinal percussion (90% of cases)
- very high ESR (>50-100) ver common (80-90% of cases)
- may have neuro deficits. Positive tension tests
What is the top of ddx list for neuropathic pain in patients <40? What are other causes?
- Disc herniation
- radicular: spondylolysis/spondylolisthesis, structural instability, spinal infection, nerve root adhesions, fracture, spinal stenosis
- peripheral: diabetic, other peripheral neuropathy, piriformis syndrome
spinal stenosis vs disc herniation: age
> 50-60
<40-50
spinal stenosis vs disc herniation: flexion load
- may improve leg symptoms (shopping cart sign)
- may increase leg symptoms
spinal stenosis vs disc herniation: sitting
- improve leg symptoms
- increase leg symptoms (may be rapid)
spinal stenosis vs disc herniation: sustained/repetitive loading?
- may aggravate leg symptoms if done in extension
- may centralize or improve leg synths (done in any direction, although extension is most common)
spinal stenosis vs disc herniation: extension loads?
- may aggravate back or legs
- may aggravate back (and could improve leg symptoms)
spinal stenosis vs disc herniation: valsalva, dejerine’s triad
- negative
- positive (aggravating back or legs)
spinal stenosis vs disc herniation: axial compression (double ASLR)
- less likely to be positive
- more likely to be positive (especially if acute)
spinal stenosis vs disc herniation: SLR ( and other nerve tension tests)
Rarely positive
Usually positive for leg symptoms (80-90% of cases)
spinal stenosis vs disc herniation: neuro deficits
- in about 50% of cases
- more frequent (80% of cases)
spinal stenosis vs disc herniation: ataxia
- wide stance/gait, positive Romberg may be present
- normal
spinal stenosis vs disc herniation: CES
VERY RARE IN BOTH but possible (both are one of the leading cases of CES)
What is the term for leg pain with walking? What are the top three causes and what is the medical term for each?
- intermittent claudication
- Stenosis (neurogenic claudication)
- PAD (vascular claudication)
- other (e.g. hip lesion)
Stenosis vs PAD: location?
- thigh
- calf/lower leg
spinal stenosis vs disc herniation: muscle strength after walking
- increased muscle weakness
- unchanged
spinal stenosis vs disc herniation: palliative factors
- Bending or sitting
- sitting, stop walking
spinal stenosis vs disc herniation: how much time they can walk before pain
- variable
- consistent
spinal stenosis vs disc herniation: provocative factors
- waking downhill, increased lordosis
- walking uphill, increased metabolic demand
spinal stenosis vs disc herniation: lower extremity pulses
- present
- absent
spinal stenosis vs disc herniation: van Gelderen bicycle test
- no leg pain
- leg pain
spinal stenosis vs disc herniation: shopping cart sign
- present
- absent
PAD vs DVT: pain at rest
- made worse by walking, especially uphill, only night/rest pain when severe (may require opiates as analgesic agents):
- pain at rest
PAD vs DVT: swelling
- no swelling
- swelling of the lower limbs and may be red
PAD vs DVT: temperature
- reduced skin temperature (if anything)
- increased temperature
PAD vs DVT: observational changes
- tissue loss (ulceration); muscle wasting; loss of hair; dry; thin; brittle nails
- dilation of superficial veins
PAD vs DVT: palpation
- pulses are diminished or absent, presence of bruits
- palpable tender, hard “cord” along the vein
With a suspected spinal stenosis, do a basic low back physical exam and (4 things)
- sustained extension (30-60 seconds, especially if extension did not bother the patient)
- repeat neurological exam after patient walks to point where they get symptoms
- Romberg test
- check lower extremity pulses
Ancillary studies for stenosis
- radiograph (looking for degeneration such as disc thinning, facet thickening, spur) (used to R/O infection, tumor, spurs in IVF) (not enough to make the diagnosis
confirm with MRI (or sometimes CT)
- relative lumbar spinal stenosis = narrowing =12mm diameter
- absolute lumbar spinal stenosis = narrowing = 10mm diameter
If they need surgery: electromyoraphic paraspinal mapping (needle EMG on paraspinal muscle to map which muscles are involved and to what degree nerve action potentials are affected.
Ancillary studies for PAD (vascular claudication)
- duplex/Doppler ultrasound (looking at blood flow)
- ankle-brachial index (ABI) (<0.90) (blood pressure with ultrasound, to see blood flow in lower extremity vs upper
- MRA (angiography) = GOLD STANDARD
In a patient who had both stenosis and PAD, what ancillary test is required to tell which condition is causing their symptoms
- treadmill test with an incline
- stenosis patient can walk further without pain because the spine is flexed
- PAD patient unable to walk as far (because of increased muscle oxygen demand)
Conservative PAD management
- walking “near pain threshold” (or into the pain) at least 3x/week (supervised walking programs are more effective)
- lifestyle changes to support cardiovascular health: stop smoking, improve diet (e.g. Mediterranean)
- toe raises 3x/day. Do reps until there is pain and then 5 more
