Low Back Pain
Elizabeth Chang, MD
PGY-2
46 yo male p/w LBP x 6 mo
- Started 6 mo. ago while lifting boxes at his delivery job
- Located middle of lower back, radiates to right buttock
and right lateral aspect of right foot
- Pain worsened with sneezing/coughing
- Difficult to stand on tip toes
- Absent right ankle jerk
- Straight leg test, cannot elevate right leg above 35
degrees
- No urinary/bowel incontinence, fevers, weight loss
- Otherwise healthy
“Fun” Facts
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#2 reason patients show up in your office
84% of adults in US have LBP at some point
Up to 85% no definitive cause found
Costs the economy $100 BILLION per year
Substantial impact on lifestyle and quality of
life
• <5% have serious systemic pathology
Differential for LBP
Red Flags
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History of cancer
Age > 50
Unexplained weight loss
Symptoms of neurological compromise
Pain lasting >3 mo.
Nighttime pain
Unresponsiveness to previous therapies
History of AAA
Risk factors for spinal infection (HIV, IVDA, etc)
Radiological/Anatomic
Spondylosis: arthritis of the spine –
disc space narrowing, arthritic changes
in joint facet
Spondylolisthesis: anterior
displacement of a vertebra on the one
beneath it. Graded I – IV
Sponylolysis: fracture in the pars
interarticularis that protects the nerve
Spinal stenosis: narrowing of the
central spinal canal (bony enlargement
or thickened ligamentum flavum).
Shopping cart sign.
Ankylosing Spondylitis
• Chronic inflammatory disease of axial skeleton
• Sacroiliac joint involvement, bamboo spine on
imaging
• Males, 20-30s, HLA-B27
• Dull vague stiffness, slowly progressive over
years, worse at night, better with light activity
• Elevated ESR, CRP
• No cure, conservative management
Physical
Lumbar lordosis – inward curve
Kyphosis – outward curve
Scoliosis – sideways curve (always abnormal)
Neurologic
Radiculopathy – impairment of nerve root causing
radiating pain, numbness/tingling, muscle
weakness corresponding to specific nerve root.
Most often herniated disc. Worsened with bending
over.
• Sciatica
– set of symptoms, not a dx
– compression/irritation of one
of the 5 spinal roots
– affects posterior/lateral
aspect of leg to the foot/ankle
Cauda Equina Syndrome
• Saddle anesthesia
• Recent onset bladder dysfunction
• Severe or progressive neurologic deficit in
lower extremity
Surgery
Classifications
• Acute: <4 weeks
– Excellent prognosis, 90% full recovery
• Subacute: 4-12 weeks
• Chronic: >12 weeks
The Physical Exam 1
The Physical Exam 2
• Reflexes
– Achilles tests S1 nerve root
– Patellar tests L4
– Upgoing toes may indicate upper motor neuron instead
• Straight Leg Test (for sciatic nerve irritation)
– Pain below knee at <70 degrees worsened by ankle
dorsiflexion  suggests L5/S1 tension from disc herniation
• Sitting Knee Extension Test
– Should reproduce any findings from the SLT, helps clinician
discover inconsistent findings
Non-pharmacological treatments
• Exercise/PT/OT
– Proven modest benefits in subacute/chronic LBP
– Yoga, pilates, tai chi
• Spinal manipulation
– Serious adverse effects rare (<1/1,000,000)
• Acupuncture
• Massage
• TENS (transcutaneous electrical nerve
stimulation) – large study showed no difference
1st Line Pharmacotherapy
• NSAIDS
– Ibuprofen 400-600 mg QID or Naproxen 220-550
mg BID or IM ketoralac 60 mg (ER)
– Caution in elderly, nephrotoxic, GI
• Acetaminophen as alternative
– Max 4g/day
– Hepatotoxicity risk
Centrally-acting skeletal muscle
relaxants
• Limit use to 3 weeks
• Anti-cholinergic side effects
– Cyclobenzaprine
– Methocarbamol
– Carisoprodol
• Baclofen
• Benzos – less evidence supporting efficacy,
high risk abuse
Opioids
• Norco, percocet, MS Contin
• Tramadol – non-opioid that acts on opioid
receptors
• Sedation, confusion, nausea, constipation,
respiratory depression in high doses
• Misuse and abuse (30-45%) – scheduled
rather than prn
• Short-term only
Anti-depressants & Anti-epileptics
• Tricyclics (amitriptyline)
– Drowsiness, dry mouth, dizziness
• Radiculopathic pain
– Gabapentin, pregabalin, topiramate
Glucocorticoids
• Limited data on efficacy and safety
• Not recommended
The End