Transcript Acute Low Back Pain - UNC School of Medicine

Acute low back pain
Opportunities for care (honest)
Tim Carey MD MPH
Dept of Medicine
Sheps Center for Health Services Research
UNC Chapel Hill
Low back pain
• 80% lifetime prevalence
• 3% of population seeks care for LBP/yr
• Average MD sees 2-4 LBP pts/wk
• Medical costs > $25 billion and rising
Back pain therapy project
TC 3-18
Tim/pres/1/24/97(6)
SCIENTIFIC INQUIRY
Hypothesis
Evidence
fails to
disprove
>
Try to disprove
>
Tentatively accept
hypothesis; test
implications
<
Results replicated,
implications prove
valid
<
Refine
practical
application
>
TOO MUCH BACK PAIN RESEARCH
Hypothesis
(new test or
treatment)
>
Try to prove
hypothesis
Weak test
offers some
support
Establish
clinic devoted
to hypothesis
<
<
>
Proclaim fact, devise billing
code, form interest group to
lobby for support, publicize
Figure 2. A contrast between the usual approach to scientific inquiry and too much back pain research.
Paradigms of LBP
•
“Don’t worry-be-happy”
- 95% of patients with LBP recover
•
“The grim slide into disability”
- High recurrence rates
- Over 1/3 of patients have chronic
symptoms
TC 2-7
EXPLANATORY MODELS IN BACK PAIN
• ALLOPATHIC: RUPTURED DISC, “BLACK BOX”
• CHIROPRACTOR: SUBLUXATION OF THE SPINE
• PHYSICAL THERAPY: STRENGTH, INFLAMMATION
• PATIENT: DISC, ARTHRITIS
• SUPPLIERS: WRONG BED, WRONG CHAIR
TC 7-11
THE INJURY PARAGIGM
• IF THE BACK HURTS, IT MUST HAVE BEEN INJURED
• IF SOMETHING IS INJURED, IT NEEDS REST
• INJURIES OCCUR THROUGH SOMETHING WE (OR
SOMEONE ELSE) DID WRONG
• INJURIES ARE PREVENTABLE
TC 7-10
Acute low back pain
• Affects 8% of population each year
• 40% seek care
• Second most common symptomatic reason
for care seeking at primary care MD offices
• 95% functional recovery at 6 months
• Recurrence common
TC 2-9
Chronic Back Pain
• Common, morbid, expensive
• Epidemiology unclear due to variable
definitions of the syndrome
• 1992 estimate of chronic LBP in NC=3.9%
– Functionally impairing and
– >3 months in duration (or >25 episodes per year)
• 2006 estimate 8-9% using same definition
• Care seeking also increased
Why are physicians uncertain?
• Voluminous data
• Limited training in LBP in primary care
• Specialists see very different diagnostic
spectra from each other
• Patient expectations may not be congruent
with caregiver ability to affect the natural
hx of the illness
TC 7-18
What hurts?
•
•
•
•
•
•
Discs
Annulus fibrosis
Facet joints
Muscles
Ligaments
Inter-individual variability in sensitivity to
somatic input
When to see a physician?
•
•
•
•
•
•
Unrelenting, severe pain
Leg weakness
“Red flag’ underlying conditions
Significant trauma
Symptoms not improving after 2 weeks or so
Off work for > 5 days (variable depending on
job)
Initial evaluation
Look for the “red flags”
•
•
•
•
•
•
•
Weight loss
Fever
Hx non-skin malignancy
Chronic steroid use, osteoporosis
Significant trauma
Hx IVDA
Progressive neurologic deficit
Serious causes of acute low back pain
• Metastatic malignancy
– Primary malignancy
• Infectious processes
• Cauda equina syndrome
– Central disc herniation
• Compression fracture
• (Spinal stenosis)
• (Acute disc herniation)
Physical exam
• Touch what hurts
• Gait, observation, Waddel signs for chronic
symptoms
• Straight leg raise
• Knee jerk
• Ankle jerk
• Foot dorsiflexion
• (Sensory exam)
By Gary Larson, It Came From the Far Side
TC C-1
Patients Eligibility Requirements
Patients with low back pain
• Age > 20 and < 75
• < 10 weeks duration this spell
• No previous care for this spell
• No back surgery or chymopapain ever
• No history of non-skin malignancy
• Not pregnant
• Had home telephone
• English speaking
NC Back Pain Project
TC 7-19
NC Back Pain Project Cohort Study Interview
Schedule
Index Visit
Enrolled
Baseline
Interview
2 wk 4 wk
8 wk
12 wk
24 wk
“All Better” At Interview
TC 6-1
Figure 1.-Cox-Model Curves of the Time from the Initial Visit to Functional Recovery among Groups of Patients with
Low Back Pain Treated by Various Types of Providers. The confidence intervals overlap (data not shown), with no
statistically significant differences among the six strata. Data have been adjusted for base-line differences in functional
status (the Roland-Morris score), the presence or absence of sciatica, income, duration of pain before the index visit,
workers' compensation status, and educational level. Because of overlap, not all of the six curves are visible
From: Carey: N Engl J Med, Volume 333(14).Oct 5, 1995.913-917
Total Outpatient Direct Medical Charges per
Episode of Low Back Pain
STRATUM
MEAN
ADJUSTED MEAN*
Urban Primary Care
$478
$508
Rural Primary Care
$540
$474
Urban Chiropractor
$508
$783
Rural Chiropractor
$554
$611
Orthopedist
$809
$746
HMO
$365
$435
*Adjusted for baseline functional status sciatia, income, duration of pain, and worker’ compensation
TC 7-4
Carey Slides 13/Kathë
Recurrence of LBP from 6-22 Months Among Those
Completely Recovered by 3 Months (N=754)
Percent Recurrence
60
50
40
30
20
10
0
Urban
Prim
N=137
Rural
Prim
N=157
p = 0.01
NC Back Pain Project
Urban
Chiro
N=128
Rural
Chiro
N=166
Practitioner Strata
Ortho
HMO
N=72
N=54
No Recurrence
Mild Recurrence
Severe Recurrence
Imaging procedures
• Who needs radiographs (x-rays)?
• High vs. low risk patients.
• Non-specific ‘wear and tear’ findings
common
• Guidelines available for 10 yrs but imaging
procedures persist.
• How many views?
- 5 views vs. 3. How much incremental
benefit is gained by two additional views?
TC 3-30
By Cary Larson, It Came From the Far Side
TC C-2
Medications
•
•
•
•
•
•
Very commonly used in LBP
Analgesia
Role of NSAIDS
Muscle relaxants
Narcotic analgesics
Herbal remedies
Injection therapy
• Limited role in new onset LBP
• Modest efficacy in the most optimistic studies
• Substantial non-specific effect of any injection
Physical therapy
•
•
•
•
•
Evaluation, advice, physical treatments
May include manual therapy
Minimal standardization
Little research in the past
Probably not helpful in the first several weeks
of acute LBP
• May be useful in chronic LBP if the approach is
an active one
Spinal manipulation
•
•
•
•
Commonly used across several specialties
Excellent patient satisfaction
Probably effective compared with no treatment
Probably not substantially different in clinical
outcome compared with usual allopathic treatment
(evaluation, advice, meds)
• Somewhat more expensive
Acupuncture
• Biologic rationale unknown but substantial
historical use
• Non-standardized intervention, substantial
variability among practitioners, across
theories
• Recent RCT negative when compared with
medical treatment or massage
Early return to work
• Work disability is a large portion of the social cost of
LBP
• Pure educational programs are ineffective
• Mounting evidence that active case management
stressing early return to work or modified work
reduces cost and improves function
• Need to streamline process of modifying work
• Early communication with a receptive supervisor is
key
• Exercise is good
Utility of surgery
• Modest evidence for substantial
improvement in leg pain in sciatica if not
improved in 6 weeks of conservative rx
• Little consensus as to indications for and
results from fusion for chronic LBP
– Randomized trial demonstrated modest benefit in
disc surgery, degenerative spondylolisthesis
IDET
Intradiscal electrothermal therapy
•
•
•
•
•
•
Novel procedure, percutaneous
Heats disc to > 60 deg C
Several month rehab necessary
Case series data encouraging
European RCT of similar procedure negative
Urgent need for US RCT
PATIENT SATISFACTION
How would
you rate…
MD/HMO
Chiropractor
Patients
Patients
(N=1027)
(N=606)
Percent answering “Excellent”
…the information
you were given?
30.3
47.1
…the way the
doctor treated your
back problem?
31.5
52.1
…the overall results
of your treatment?
26.5
42.1
(The P value for each question asked is P<0.0001)
TC 7-5
PATIENT SATISFACTION
Did the doctor who
enrolled you in this
study…
…take a detailed history
of your back pain?
…do a careful examination
of your back?
…explain the cause of your
back problem clearly
(Cont.)
MD/HMO
Patients
(N=1027)
Chiropractor
Patients
(N=606)
Percent answering “Yes”
68.4
88.4
79.9
96.1
74.6
93.6
(The P value for each question asked is P<0.0001)
TC 7-6
Incidence of Chronic Low Back Pain
Developing from Acute Low Back Pain
Of 100 patients presenting for acute low back pain:
7-8 will still have significant symptoms 3
months later
25 will have mild back pain but be able to
perform their usual daily activities
TC 7-7
Where to refer?
• Physical therapy can be very helpful, but how to
find the right one?
- Exercise over modality
• Orthopedic/neurologic surgeons
- Is an operation needed?
• PM+R
• Multi-specialty pain management including
anesthesiology
• Primary care with a hobby
- Kaiser-Permanente model
TC 6-30
Pain modulating therapy
• Tricyclic antidepressants
– Dose titration
• (SSRI’s)
• Possibly SNRI’s
• Anti-seizure medication
– Gabapentin, etc.
Chronic narcotic therapy
• Indicated in patients if not operative candidates
• Limited RCT evidence shows analgesia but not
improved functional status
• Requires clear understanding of duration and
conditions of renewal
• Longer duration analgesics preferred
– MS Contin
– Methadone, etc.
Exercise
• Aerobic exercise
• Exercise more important than any specific
maneuver
• Dose (duration) matters
• If possible, group reinforcement useful
– Cognitive-behavioral therapy
– Lay-led groups
Hayden, Ann Intern Med 2006
What interventions work?
• Surgery for selected patients in avoiding long-term leg
pain after minimum of 6 weeks of symptoms
• Active physical therapies
- exercise
- education
• Receptive work environment
• Medications have only a modest role
• Early return to normal activities
TC 2-1
What Doesn’t Work
-Most modalities provide only transient
relief
-Traction is not useful
•Corsets only occasionally useful
•Spinal fusion has a “success” rate of 50%
•Epidural steroids, etc. of transient benefit
•Spinal manipulation of unclear benefit in
chronic LBP
TC 7-12
The physicians role
•
•
•
•
•
Evaluation
Reassurance
Symptom relief
Encouragement of return to normal activity
Appropriate referral