1. Low Back Pain: Approach to the patient in the E.D.
Lala M. Dunbar, M.D., Ph.D.
Clinical Professor of Medicine
LSU HSC

2. Epidemiology
60 – 90% of adults experience back pain at some point in their life.
-  incidence age y.o.
- 90% resolve in 6 weeks
- 7% become chronic
- M/ F equally affected
85% never given precise pathoanatomical dx
5th Leading reason for medical office visits
2nd to respiratory illness as reason for symptom-related MD visits

3. Epidemiology (cont.) #1 Cause and #1 Cost of work related disability
Healthcare expenditures $90 Billion (1998)
- $26.3 Billion attributable to back pain

4. Important Questions 1. Is systemic disease the cause?
2. Is there social or psycological distress that prolongs or amplifies symptoms?
3. Is there neurologic compromise that requires surgical intervention?

5. To Answer These Important Questions
1. Careful History and Physical Exam
2. Imaging and Labs WHEN indicated

6. Differential Diagnosis of Low Back Pain

7. Evaluation in older adults
Probabilities change
Cancer, compression fractures, spinal stenosis, aortic aneurysms more common
Osteoporotic fractures without trauma
Spinal Stenosis secondary to degenerative processes and spondylolisthesis more common
Increased AAA associated with CAD
Early radiography recommended

8. Clues To Systemic Disease
Age
History of Cancer
Fever
Unexplained Weight Loss
Injection Drug Use
Chronic Infection Elsewhere
Duration and Quality of Pain
-Infection and Cancer not relieved supine
Response to previous therapy
h/o inflammatory arthritis elsewhere

9. Imaging Plain Radiography limited to patients with:
-findings suggestive of systemic disease
-trauma
Failure to improve after 4 to 6 weeks
CT and MRI more sensitive for cancer and infections – also reveal herniation and stenosis
Reserve for suspected malignancy,infection or persistent neurologic defecit

10. MRI
Shows tumors and soft tissues (e.g., herniated discs) much better than CT scan
Almost never an emergency
Exception: Cauda equina syndrome 10

11. CT Scan Shows bone (e.g., fractures) very well
Good in acute situations (trauma)
Sagittal reconstruction is mandatory
Soft tissues (discs, spinal cord) are poorly visualized
CT-myelogram adds contrast in the CSF and shows the spinal cord and nerves contour better 11

12. Abdomen, X-ray, Anteroposterior View
1. 1st Lumbar vertebra
2. 2nd Lumbar vertebra
3. 3rd Lumbar vertebra
4. 4th Lumbar vertebra
5. 5th Lumbar vertebra
6. T12
7. Twelfth rib
8. Sacroiliac joint
9. Sacrum
10. Sacral foramen
11. Ilium
12. Pelvic brim
13.Superior ramus of pubic bone
14. Pubic symphysis

13. Lower Third of Spinal Cord, MRI
1. Vertebral body 2. Spinal cord 3. Conus medullaris 4. Intervertebral disc 5. Filum terminale (internum) 6. Subarachnoid space

14. Sagittal Section through the Spinal Cord
Intervertebral disc
2. Vertebral body
3. Dura mater
4. Extradural or epidural space
5. Spinal cord
6. Subarachnoid space

15. Lumbrosacral Dermatones

16. Common Pathoanatomical Conditions of the Lumbar Spine

17. Disc Herniation – Physiology
Tears in the annulus
Herniation of nucleus pulposus 17

18. Disc Herniation – Physiology
Compression of the nerve root in the foramen leads to pain 18

19. Lumbar Disc Herniation – Treatment
Conservative Tx.
Moderate bed rest
Spinal manipulation
Physical therapy
Medication
NSAIDs
Muscle relaxants
Rarely narcotics
Surgical Tx.
“Microdiscectomy”
Less than half of an inch incision
Go home the same or next day
Good results in up to 90% of cases 19

20. Results of Surgical Treatment
Good outcome in 80-90% of cases
Residual pain may last up to 6 months postop
Results are worse if pain was present for over 8 months before the operation (permanent nerve damage?) 20

21. Low Back Pain Second most common cause of missed work days
Leading cause of disability between ages of 19-45
Number one impairment in occupational injuries
80 billions spent each year
80% of general population will have back pain at some time during their lives 21

22. Low Back Pain Most episodes of LBP are self limited
These episodes become more frequent with age
LBP is usually due to repeated stress on the lumbar spine over many years (“degeneration”), although an acute injury may cause the initiation of pain 22

23. Disc Degeneration – Physiology
With age and repeated efforts, the lower lumbar discs lose their height and water content (“bone on bone”)
Abnormal motion between the bones leads to pain 23

24. Disc Degeneration – Treatment
Conservative Tx.
Moderate bed rest
Spinal manipulation
Physical therapy
Medication
NSAIDs
Muscle relaxants
Rarely narcotics
Surgical Tx.
Lumbar fusion OR
Replacement with artificial disc 24

25. Indications for Surgical Treatment
Low back pain for at least 2 years
Incapacitating
Resistant to physical therapy and medication
Positive MRI findings (degenerative changes) at L4-5 and/or L5-S1
For selected cases:
Concordant pain on discography
Psychological evaluation 25

26. Natural History
Recovery from nonspecific LBP generally rapid – 90% within 2 weeks – some studies less rapid (2/3 at 7 weeks)
Herniated Discs – slower to improve – only about 10% considered for surgery after 6 weeks
With surgery, no earlier return to work – symptomatic and functional outcome sometimes better

27. Physical Examination Fever – possible infection
Vertebral tenderness - not specific and not reproducible between examiners
Limited spinal mobility – not specific (may help in planning P.T.
If sciatica or pseudoclaudication present – do straight leg raise
Positive test reproduces the symptoms of sciatica – pain that radiates below the knee (not just back or hamstring)
Ipsilateral test sensitive – not specific: crossed leg is insensitive but highly specific
L-5 / S-1 nerve roots involved in 95% lumbar disc herniations

28. Assessment of Function
98% disc herniations: L4-5; L5-S1
Impairment: Motor and Sensory L5-S1
L5: Weakness of ankle and great toe dorsaflexion
S1: Decrease ankle reflex
L5 & S1: Sensory loss in the feet

29. STRAIGHT LEG RAISE TEST
The straight leg raise test is positive if pain in the sciatic distribution is reproduced between 30° and 70° passive flexion of the straight leg. Dorsiflexion of the foot exacerbates the pain

30. Waddell Signs For Non-organic Pain
Superficial non-anatomic tenderness
Pain from maneuvers that should not ellicit pain
Distraction maneuvers that should ellicit pain BUT don’t
Disturbances not consistent with known patterns of pain
Over-reacting during the exam
Not definitive to rule out organic disease

31. Imaging Studies Progressive Neurologic Defecits Failure to Improve
Hx of Trauma
Risk for Malignancy or infection

32. Nerve Root Pain Associated w/ Radiculopathy Sciatica -herniated disk
-foramenal or spinal stenosis
-ligamentous hypertrophy
-other space filling lesions: cysts, tumor, abscess
-viral or immune inflammation
-can occur w/ peripheral nerve involvement
Spinal stenosis
-neurogenic claudication (pseudo claudication)
1 or both legs
-radiation to buttocks, thighs, lower legs
-pain increase with extension (standing, walking)
-pain decrease with flexion (sitting, stooping forward)

33. Indications for Surgical Referral

34. Therapy: Non-specific LBP
NSAIDS
Muscle relaxants
Use on schedule than p.r.n.
Spinal manipulation/ P.T. (effects limited)
Delay referral until pain persists >3 weeks
50% will improve b/f this time period
Rapid return to normal activities
Avoid heavy lifting, trunk twisting, vibrations
Alternative Tx: acupuncture and massage
Surgery- ineffective unless:
sciatica, pseudoclaudication, spondylolisthesis

35. Therapy: Herniated Disks
If no evidence cauda equina or progressive neurologic defecit:
Treat non-surgically minimum one month
Treat similar to non-specific LBP
Limited narcotics
Epidural steroids (helps in some)
If severe pain or neuro defecits persist:
CT/ MRI / consider for surgery
Diskectomy
Improved relief vs. non-surgery at 4 yrs./ ? 10yrs.
Percutaneous and laser less effective than std.
Arhroscopic techniques techniques comparable to std. surgery

36. Therapy: Spinal Stenosis
Conservative management may be useful
For severe persistant pain decompressive laminectomy
Surgery – better pain relief and functional recovery
30% recurrent severe pain in 4 years
10% reoperated

37. Therapy: Chronic LBP Sx often difficult to explain
Intensive exercises help (hard to maintain)
Anti-depressant therapy useful if depressed
Long term opioids – not recommended
Referral to pain center
Massage therapy is promising
Therapeutic goals – optimize daily function

38. Long Term Outcomes Herniated Discs w/o neurologic deficits
Diskectomy - > relief at 4 yrs; ? Better at 10 yrs
Microdiskectomy – similar to standard
Laser Diskectomy – less effective
Arthroscopic diskectomy - promising

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