Low Back Neurological Assessment Flashcards
Leg and back pain with nerve involvement
Cord lesions - only upper lumbar lesions
Nerve root lesions - Include cauda equina
Peripheral nerve lesions - Sciatica, femoral, neuropathy)
Leg and back pain without nerve involvement
Deep referred pain - From Si and lumbar structures
Separat lesions - along the kinetic chain
Deep referred pain syndromes
irritated joints of muscles in the spine often feel pain in other areas despite no pinched or injured nerves
Sclerotomal pain
can come from any tissue with the same embryological origin
Pain is experienced from all of these tissues innervated by the same nerve or along sclerotomes
Sclerotogenous Referred Pain Patterns
From deep somatic tissue
Leads to:
Deep - aching, diffuse pain
Sclerotomal segmental pattern
Often more proximal than distal
Pain often spreads out over time. Referral territory grows. Pain may skip over regions
When patients have leg or arm symptoms with spinal pain one of the top priorities are _______ or not
Neuropathic
The leg rules!
If there are no leg symptoms, not nerve damage generally
Neuropathic Assessment: 5 key clues
Leg pain: territory, quality, more intense than LBP
Paresthesia: territory
Lumbar tension tests
Neurological deficits or abnormalities
Lumbar joint loading procedures that cause immediate leg sx
Neuropathic tool: Radicular syndrome - Leg Pain
Location - must be past the knee. may be dermatomal. feels superficial
Quality - Often sharp, stabbing, electrical, sharp, painful cold, lancinating
Severity - Worse than back pain
Affected by spinal position
Nerve root pain
in most cases nerve root pain should not be expected to follow a specific dermatome but it does have use in diagnosis of radicular pain.
Exception is the S1 root that often follows the dermatome
NT Radicular Syndrome: leg paresthesia
Often present and more likely to follow a dermatomal distribution
NT radicular syndrome: Sensory, motor, reflex
May be one or more deficits usually corresponding to the same nerve root
Three components of Neurological components
Sensory
Motor
Reflex
Dermatomal Sensory Distribution explanation
Most often due to nerve root compression from a herniated nerve root disc
Sensory disturbance may set in before muscle weakness or atrophy
L4 pure patch
Medial thigh
L5 Pure Patch
Medial side of big toe
S1 pure patch
5th toe and interdigital web
Sciatic nerve DTR
S1, S2
Achilles tendon
Femoral nerve DTR
L3, L4
Patellar tendon
Sciatic nerve DTR
L5, S1
Hamstring tendon
S1 muscle tests
Toe flexors - Tibial n.
Ankle evertors - Peroneal/Fibularis
Plantar flexion - Tibial n.
L5 muscle tests
Big toe extensors - Peroneal nerve
Hip abductors - Superior gluteal nerve +LR 11
L4 muscle tests
Ankle dorsiflexion - Deep peroneal nerve
Ankle inversion - Deep peroneal/fibular nerve
Radicular syndrome nerve tension tests should _____
Often reproduce leg symptoms
Straight Leg Raise
A passive test
Main tension is for the L4, L5, S1 nerve roots (and sciatic nerve)
Positive test: Creating or aggravating lower extremity pain. Hard positive reproduces pain past the knee.
SLR test validity
Sensitivity is thought to be good for patients with
posterolateral disc herniations.
Poorer sensitivity (but can be present) for patients with: Spinal stenosis, spondylolisthesis, midline and medial disc herniations
Tension tests can be used to confirm a positive SLR
Braggard, Bowstring, Bonnet
Maximum SLR
SLR, Flex neck, push led medially, invert foot
Femoral stretch test
reverse SLR
stretches femoral nerve and the L2, 3, 4 nerve roots
Radicular Syndrome Tool - Spinal loading procedures
Rapid reproduction of leg symptoms possible
Leg pain can result from Radicular Syndrome with ____, ____, _____
Forward flexion, extension + rotation, valsava maneuver
Radiculitis
Inflamed nerve root Neuropathic pain (dermatomal) Paresthesia (dermatomal) Positive tension tests Reproduce the pain by loading the spine Increased sensitivity
Radiculopathy
Compressed/torn nerve roots
Motor deficits (muscle weakness, atrophy)
Hyporeflexia
Dermatomal sensory loss
think deficits
Cauda Equina Syndrome: Referral
Very uncommon
But it requires urgent referral (same day)
Cauda Equina Syndrome: Causes
Large midline disc herniation (top cause)
Severe spinal stenosis (top cause)
Tumor
Infection hematoma
Affected nerve roots: S2-4
Damage can occur in damage
Saddle Anesthesia
With CES
80% sensitivity
Bilateral (maybe unilateral)
test with light touch and sharp
Strong indicator with unrinary dysfunction
Altered perineal sensation may be most important predictor of ___________
Impending bowel or bladder dysfunction
Associated with Saddle Anesthesia
CES effect on bladder
Painless urinary retention (LR+ = 18; LR- = 0.1) and overflow incontinence
Incomplete: Urinary difficulty, altered sensation, loss of desire to void, poor urinary stream, need to strain to urinate
Strong indicator with saddle hypesthesia
CES effect on bowel
Inability to control defecation
Sense rectal fullness
Decreased anal sphincter tone
absent anal wink
CES sexual dysfunction
Decrease in genitalia sensation
Inability to get or maintain an erection
Reduced sensation during sexual stimulation
Symptoms occur ____ after neurological compromise in __% of the cases.
Unfortunately ___, ___, and _______ abnormities may not be recognized in the short time frame
Less than 24 hours, 90%
Urologic, bowel, sexual dysfunction
Incomplete CES
better prognosis with immediate intervention
Patient has altered urinary sensation, loss of desire to urinate, weak stream, or may have to push to void
Complete CES
Urinary retention, overflow incontinence
Complete saddle anesthesia
Pudendal (neuropathy) Nerve Lesion
Unilateral or bilateral perineal pain
May be a burning or a sensation of a foreign body in the rectum or vagina
Pudendal Nerve Lesion
Alcock’s syndrome
Urinary incontinence or sexual dysfunction
Often related to a fall on the butt or traction injuries, or biking
Aggravated by sitting
DDX with CES
Peripheral nerve damage DDX for CES
Femoral nerve
Lateral cutaneous femoral nerve
Sciatic nerve
Common peroneal
PNS Lesions (entrapments and compression)
Piriformis syndrome
Peroneal nerve compression
Femoral neuropathy (secondary to pelvic tumor)
PNS lesions (diseases)
Polyneuropathy
Diabetes
Alcoholic neuropathy
Vitamin B12 deficiency
Femoral compression most often occur in _____ _____
Iliac Fossa
Causes of femoral neuropathy
Diabetic mononeuropathy Tumor Psoas or ilicus hematoma Injury (surgery) Inflammatory conditions (such as rheumatoid bursitis)
Femoral nerve damage may result in:
Unilateral lower extremity pain that may involve:
The groin, anterior thigh and sometime the lower leg
Patient may flex the hip for pain relief
Femoral damage sensory changes
Numbness and paresthesia on the anterior or medial thigh
Motor symptoms of femoral nerve damage
Hip flexors and knee extensors are affected first
Sudden knee buckling may be initial symptom (seen in uneven road or step ups and down)
None of the affected muscles are below the knee
Femoral nerve physical exam findings
Weakness with iliopsoas
Weak quadriceps
Decreased or absent patellar reflex
Lumbosacral plexus damage
Mimics damage to femoral nerve but with the addition of adductor weakness
Affects adductor longus and magnus
Femoral stretch test
Stretches femoral nerve
Stretches L2, 3, 4
Creates sharp anterior thigh pain
Diabetic amyotrophy
Multiple lumbosacral nerve roots are affected but sometimes only the femoral nerve
Sudden severe lower extremity, Muscles weakness precedes the onset of pain, muscle testing the femoral nerve is painful
Patients usually have well controlled type 2 DM and are middle aged or older. Weight loss is a frequent accompanying symptom
Painful femoral nerve involvement should trigger an appropriate ______ _____
Diabetes evaluation
Diabetic polyneuropathy
The majority of patients with diabetes have LS plexus involvement rather than just femoral nerve involvement
Symptoms are bilateral and more distal
Classic diabetic peripheral neuropathy
Symmetric/polyneuropathy
Results in sensory loss in extremities - usually in feet and hands in a stocking and glove distribution (sensory changes occur first)
Causes burning
Exaggeratedly intense or distorted experience of touch
Late findings are autonomic and motor deficits. Can lead to gait abnormalities
Classic diabetic peripheral neuropathy ancillary studies
CT should always be done to rule out mass
EMG and nerve conduction may be necessary to determine where the lesion is
Femoral nerve treatments
Hematoma or tumor is removed
Diabetes is treated
If secondary to surgery then it recovers spontaneously in weeks or months
Meralgia Paresthetica pathophysiology/etiology
Entrapment of nerve as it passes the inguinal ligament near the ASIS
Tight pants, obese, pregnancy, diabetes, local trauma, or extended sitting/cycling/walking
40-60 yo
Meralgia Paresthetica presentation
Lateral femoral cutaneous (anterolateral thigh) distribution of numbness, tingling or dull pain (bilateral in 20%)
No motor involvement
Meralgia Paresthetica Treatment
Change to looser pants, losing weight
OTC pain meds
Conservative care
Peroneal Nerve Entrapment
Most are due to external compression or stretching of the nerve near the fibular head
Some or all of these:
Pain is not common, foot drop may be partial or complete
Ankle dorsiflexion, great toe extension or eversion
Numbness over the lateral aspect of lower leg
Ankle inversion may increase pain
Normal achilles reflex
Peroneal Nerve Entrapment Causes
Postural factors (sitting with legs crossed, etd.) Repetitive motion (sports, running) Weight loss Trauma Iatrogenic
Tibial nerve affects ____
Flexors
Common peroneal nerve controls _____
Extensors
Myelopathy
Spinal cord lesions (uncommon) compression?
Common at L2
Cord problems are not commonly associated with LBP
Causes of cord compression
INJURY
TLJ compression fracture
Upper lumbar disc lesion
Spinal canal stenosis
DISEASE
Tumor
Stenosis
The narrowing of the spinal canal due to degenrative changes:
disc thinning, facet enlargment, thickening of ligamentum flavum
Cord compression
Presents with common leg symptoms
Urinary incontinence
Constipation
Impotence
