ABORDAGEM AO PACIENTE COM LOMBALGIA CRÔNICA

CONDUTA NO PACIENTE COM LOMBALGIA E ABORDAGEM FARMACOLÓGICA E NÃO-FARMACOLÓGICA DOS PACIENTES COM LOMBALGIA CRÔNICA:

APPROACH TO IMAGING:

Indications — Up to 90 percent of patients with back pain alone (ie, absence of sciatica or systemic symptoms) improve rapidly. Given the favorable prognosis, imaging studies are infrequently needed. This is particularly true for younger women; gonadal radiation from a two view radiograph of the lumbar spine is equivalent to radiation exposure from a chest xray taken daily for more than one year. The American College of Physicians (ACP) advises that diagnostic imaging is indicated for patients with low back pain only if they have severe progressive neurologic deficits or signs or symptoms that suggest a serious underlying condition. They also emphasize the potential harms to patients caused by excessive imaging. Imaging is not necessary during the first 4 to 6 weeks, in the absence of any of the following criteria.

Progressive neurological findings
Constitutional symptoms
History of traumatic onset
History of malignancy
Age ≥50 years
Infectious risk such as injection drug use, immunosuppression, indwelling urinary catheter, prolonged steroid use, skin or urinary tract infection
Osteoporosis

The American College of Radiology has identified 10 "red flags", which indicate a more complicated status and may be helpful in identifying patients in whom radiographs, or other imaging studies, would be appropriate.

Plain radiographs — If clinical improvement has not occurred after four to six weeks, plain anteroposterior and lateral radiographs of the lumbosacral spine may be useful (two views total). The goal of radiography is to rule out tumor, infection, instability, spondyloarthropathy, and spondylolisthesis.

Joint guidelines from the American College of Physicians and the American Pain Society (2007) explicitly recommend that "Clinicians should not routinely obtain imaging or other diagnostic tests in patients with nonspecific low back pain" and reserve imaging for patients with severe or progressive neurologic deficits or when serious underlying conditions are suspected on the basis of history and physical examination.

CT and MRI scanning — Computed tomography (CT) and magnetic resonance imaging (MRI) are more sensitive than plain radiographs for detecting infection and cancer, and can show herniated discs and spinal stenosis. However, MRI or CT findings may be incidental and unrelated to the etiology of low back pain.

Early or frequent use of scanning is not recommended for most patients. CT or MRI is indicated for progressive neurologic deficits, high suspicion of cancer or infection, and should be considered for those with more than 12 weeks of persistent low back pain. When available, MRI is preferred over CT scan for better visualization of soft tissue and absence of radiation exposure. A more detailed discussion of testing modalities is presented separately.

INDICATIONS FOR REFERRAL — Referral, usually to a neurosurgeon or orthopedist specializing in back surgery, is indicated when any of the following signs or symptoms are present:

The cauda equina syndrome – Typical features are bowel and bladder dysfunction (urinary retention), saddle anesthesia, and bilateral leg weakness and numbness. The cauda equina syndrome is a surgical emergency.
Suspected spinal cord compression – This may present as acute neurologic deficits in a patient with cancer and risk of spinal metastases, and requires emergent evaluation for surgical decompression or radiation therapy, with specific management determined by the underlying pathology.
Progressive or severe neurologic deficit

Patients may also be referred to a neurologist or physiatrist if any of the following are present:

Neuromotor deficit that persists after four to six weeks of conservative therapy
Persistent sciatica, sensory deficit, or reflex loss after four to six weeks in a patient with positive straight leg raising sign, consistent clinical findings, and favorable psychosocial circumstances (eg, realistic expectations and absence of depression, substance abuse or excessive somatization.


SELF-CARE
Self-care advice — All
patients with low back pain, regardless of duration or severity, should
be instructed in self-care techniques. Initial advice should stress the
importance of maintaining activity as tolerated.
Patients who require a period of bedrest to relieve severe symptoms
should be encouraged to return to normal activities as soon as possible.
A
systematic review of randomized trials has found that bedrest did not
improve either function or pain, compared to usual activity, for
patients with sciatica.
Advice to remain active was as effective as 'standard' physical therapy
(any combination of exercises, mobilization and/or manipulation,
superficial heat or cold, and advice) for improvement in function in a
randomized trial.
However, patients randomly assigned to physical therapy were more
likely to report a perceived benefit than those receiving activity
advice.
Self-care education books based on evidence-based guidelines (such as The Back Book) are an inexpensive and efficient method for supplementing clinician-provided back information and advice.
Several randomized trials have shown self-care education books to be
similar in effectiveness, or only slightly inferior, to interventions
with higher direct costs such as supervised exercise, massage,
acupuncture, and spinal manipulation.
Lumbar supports — There is no compelling evidence that lumbar supports are effective in patients with subacute and chronic low back pain.
A systematic review of eight trials for treatment of low back pain
found overall poor study quality, inadequate randomization, and
generally low compliance with the intervention. The conclusion was that
evidence conflicted whether lumbar supports used as supplements to other
treatments were effective in the treatment of low back pain.
PHARMACOLOGIC THERAPIES — Medications
are commonly used for patients with low back pain. Most evidence of
efficacy comes from short-term trials, so the relative benefits and
safety of use for prolonged periods in patients with subacute and
chronic pain is uncertain. Thus, limiting the duration of use for most
medications is reasonable.
Analgesics — Several
classes of analgesic medications are effective for moderate, short-term
pain relief in patients with subacute or chronic low back pain. Each
class of medication is associated with unique trade-offs involving
benefits, risks, and costs.
Acetaminophen and nonsteroidals — Short courses of nonopioid analgesic medications, such as acetaminhophem or
nonsteroidal antiinflammatory drugs (NSAIDs), are often considered
first-line pharmacologic options for acute exacerbations of subacute or
chronic low back pain.
A systematic review of randomized trials found that nonsteroidal
medications were effective for short-term symptom relief in patients
with subacute and chronic low back pain.
Nonsteroidal
antiinflammatory drugs are associated with well-known gastrointestinal
and renal side effects. Additionally, exposure to COX-2 selective
inhibitors is associated with an increased risk of myocardial infarction.
Cardiovascular and gastrointestinal risk factors should be assessed
before prescribing NSAIDs and the lowest effective dose should be
prescribed for the shortest period necessary.
Acetaminhophen is
not known to be associated with myocardial infarction or
gastrointestinal bleeding. One systematic review found no clear
difference between acetaminophen and NSAIDs for pain relief in patients
with low back pain.
However, systematic reviews of patients with osteoarthritis (not
limited to the back) consistently found acetaminophen slightly inferior
to NSAIDs for pain relief.
Opioids — Two
systematic reviews and meta-analyses of opioid use specifically for
chronic back pain identified few high-quality or long-term trials.

• One
  meta-analysis found that opioid medications, compared with placebo or
  nonopioid analgesics, did not significantly reduce pain in patients with
  chronic low back pain.
  One included trial (n = 213) found opioids superior to placebo for
  improvement in pain intensity (standardized mean difference [SMD] 0.40,
  95% CI 0.77-0.07). However, patients in this study were treated with
  opioids prior to allocation to continued opioids or placebo during a
  run-in-period, so poorer outcomes in the placebo group could have been
  due in part to opioid cessation and withdrawal. Three other trials found no significant differences between opioids and control (placebo or nonopioid analgesics).
  
• The other meta-analysis found that tramadol was
  minimally more effective than placebo for improving function (SMD 0.17,
  95% CI 0.04 - 0.30) and for pain relief (SMD 0.71, 0.39-1.02) in three
  trials, but in a fourth trial there was no difference between opioids
  and naproxen for either pain relief or function.
  Systematic reviews of opioids for chronic non-cancer pain conditions in
  general (not restricted to low back pain), however, find consistent
  evidence that opioids are moderately effective for pain relief, though
  the trials often do not address whether pain relief is associated with
  functional improvement.
  
• Two
  trials published after the meta-analyses were conducted found that
  treatment for 12 weeks with opioid medications was more effective than
  placebo for chronic low back pain by 17 to 23 points on a 100-point
  scale.
  

Studies
of the use of opioids for chronic and subacute low back pain rarely
quantify the risk of important adverse events, such as abuse or
addiction. One systematic review found aberrant drug-taking behaviors in
up to 24 percent of patients receiving opioids for low back pain, but
most studies had important methodological shortcomings, including poorly
described or validated methods for identifying aberrant drug-related
behaviors.
Opioids
may be appropriate for short-term use in patients with severe acute
exacerbations of low back pain but should be used with caution for
long-term treatment of patients with chronic back pain. Opioid use
should be monitored closely, and restricted to patients not highly
vulnerable to drug dependence, abuse, or addiction.

Antidepressants — Antidepressants, particularly the tricyclic antidepressants, have been used to treat various chronic pain syndromes.

Several
meta-analyses evaluating the effect of antidepressants versus placebo
for short-term therapy (eight weeks or less) in patients with
nonspecific back pain have led to conflicting results. Longer-term trials of antidepressants for chronic low back pain are not available.
Use of antidepressants was slightly more effective than placebo for low back pain relief in two meta-analyses, with an estimated SMD of 0.41 (95% CI 0.22-0.61) for pain relief but no difference for activities of daily living. Use of tricyclic antidepressants, but not SSRIs or trazodone, was associated with the slightly improved pain relief.
Another
meta-analysis, which differed from the earlier studies in the selection
criteria used, trials included, and methods for analyzing results,
found no difference between antidepressant and placebo treatment for
relief of pain or depression and no difference between types of
antidepressants.
Three randomized trials sponsored by the drug manufacturer found duloxetine more
effective than placebo for low back pain. However, differences were
small (<1 point on 0 to 10 pain or function scales) and patients were
more likely to discontinue duloxetine compared to placebo due to
adverse effects. Duloxetine was approved by the US Food and Drug Administration in 2012 for treatment of low back pain.
Antidepressants
are associated with a higher risk of adverse events (most commonly
drowsiness, dry mouth, and dizziness) compared to placebo. Because of
small or questionable benefits and known side effects, antidepressants
are not a first-line treatment for chronic low back pain. Depression is
common in patients with chronic low back pain, and clinicians should
assess for and treat depression appropriately.
Skeletal muscle relaxants — A
systematic review found insufficient evidence to determine whether
skeletal muscle relaxants are effective for subacute or chronic low back
pain.
In the only trial evaluating efficacy of a skeletal muscle relaxant
available in the US, there was no difference in short-term reduction of
muscle spasm between cyclobenzaprine and placebo.
Pain relief and improvement in function were not reported in this
trial. Two other trials evaluated flupirtine and tolperisone, which are
not available in the US. Both medications were more effective than
placebo.
The systematic review also found skeletal muscle
relaxants associated with more central nervous system adverse events
(primarily sedation) than placebo (relative risk [RR] 2.04, 95% CI 1.23
to 3.37). In addition, carisoprodrol is metabolized to meprobamate,
a controlled substance because of its abuse and addiction potential. In
general, short-term use of skeletal muscle relaxants may be considered
as adjunctive therapy to analgesics in patients with acute exacerbations
of chronic low back pain,
but there is insufficient data to recommend their use for chronic
stable low back pain. The lack of clear benefit, well known side effects
affecting the central nervous system, and the potential for dependence
suggest that this class of medication should not be recommended for
prolonged use.
Benzodiazepines — Benzodiazepines
are often used as skeletal muscle relaxants, though not approved by the
US FDA for this indication. Data on effectiveness of benzodiazepines
for subacute or chronic low back pain is limited. A systematic review
identified three trials of benzodiazepines, but two evaluated a
benzodiazepine not available in the US (tetrazepam).
Both trials found tetrazepam more effective than placebo for short-term
pain intensity (pooled RR 0.82, 95% CI 0.72-0.94 after five to seven
days and RR 0.71, 0.54-0.93) and overall improvement (pooled RR 0.63,
0.42-0.97). The only trial evaluating a benzodiazepine available in the
US found no difference between diazepam and placebo for muscle spasm.
Because of limited evidence on efficacy and potential for addiction and
abuse, benzodiazepines should not be used for long-term treatment of
chronic low back pain, although a short course may be indicated for
acute exacerbations of chronic low back pain in patients less vulnerable
to abuse and addiction.
Antiepileptic medications — Evidence
of effectiveness of several antiepileptic medications for symptomatic
treatment in patients with subacute or chronic low back pain is
currently based on a few small studies.

• For chronic radiculopathy, two trials of gabapentin, one trial of pregabalin, and one trial of topiramate showed only small or unclear effects on pain, which may be offset by their side effects.
  
• For non-radicular low back pain, one trial found topiramate moderately superior to placebo for pain relief and slightly superior for functional improvement, but a second trial found no difference between gabapentin and placebo in pain or function.
  
• Gabapentin for spinal stenosis was evaluated in one small (n = 55) open label trial.
  The addition of gabapentin, titrated to 2400 mg/day, to a regimen of
  supervised exercise therapy, bar supports, and NSAIDs in patients
  with pseudoclaudication and spinal stenosis on CT or MRI, moderately
  improved mean pain scores, compared to no gabapentin, at four months
  (2.9 versus 4.7 on a 0 to 10 scale).
  

Additional
well-designed trials are needed before antiepileptic medications can be
recommended for low back pain (with or without radiculopathy) or spinal
stenosis.
Glucosamine — Glucosamine
has been extensively studied and is widely used to treat
osteoarthritis, particularly of the knee and hip. However, there are
little data to support its use for low back pain. In a six-month
randomized trial of 250 patients with chronic low back pain and
degenerative lumbar osteoarthritis, there were no differences in pain or
quality-of-life scores between the glucosamine sulfate (1500 mg daily)
and placebo arms. The use of glucosamine for the treatment of knee osteoarthritis is discussed elsewhere.

Anti-TNF-alpha therapy — Systemic
anti-tumor necrosis factor (TNF)-alpha therapy, which is primarily used
in the treatment of inflammatory rheumatologic and bowel disease, does
not appear to have a role for patients with chronic low back pain. This
was suggested in the FIRST II trial (n = 40), which found no differences
in pain or functional outcomes between a single intravenous infusion of infliximab or saline infusion at three-month and one-year follow-up. Epidural and intradiscal injections of anti-TNF-alpha therapy have also been evaluated.
ACTIVITY AND PHYSICAL TREATMENTS — In
addition to self care instruction, all patients with subacute and
chronic low back pain should be advised to incorporate physical activity
into their treatment plan.
Exercise therapy — A
number of different types of exercise are commonly used in patients
with subacute or chronic low back pain. Exercise programs include core
strengthening (eg, abdominal and trunk extensor), flexion/extension
movements, directional preference, general physical fitness, aerobic
exercise, mind-body exercises (eg, yoga and pilates), and functional
restoration programs. Exercise therapy is safe, readily available, helps
alleviate pain symptoms, and improve functional.

All patients with subacute or chronic low back pain should be advised to remain as active as possible.
Back schools — Back
school is an intervention consisting of education and a skill program,
including exercise therapy. Generally, lessons are provided to groups of
patients and supervised by a physical therapist or other therapist
trained in back rehabilitation. A systematic review found inconsistent
evidence on effectiveness of back schools versus placebo or wait list
controls, though most trials found no benefits.
Results were better for trials in an occupational setting and for more
intensive programs based on the original Swedish back school (providing
information on the anatomy of the back, biomechanics, optimal posture,
ergonomics, and back exercises in four group sessions over a two week
period), though any observed benefits were small.
Spinal manipulation — Spinal
manipulation is a form of manual therapy that involves the movement of a
joint beyond its usual end range of motion but not past its anatomic
range of motion (termed the "paraphysiologic zone"). Loads are applied
to the spine using short or long lever methods. Short lever
high-velocity movement of the joint is frequently accompanied by an
audible cracking or popping sound. Spinal manipulation is most commonly
associated with chiropractic (short lever techniques) but is also
performed by other spine providers, including osteopathic physicians and
physical therapists. Spinal mobilization, employing low velocity
passive movement within or at the limit of joint range, is often used in
conjunction with spinal manipulation.

For
chronic low back pain, a systematic review of randomized controlled
trials found lumbar spinal manipulation to have no advantage over
general practitioner care, analgesics, physical therapy, exercises, or
back school. Other systematic reviews concluded that spinal manipulation has a small beneficial effect, including one systematic review focusing on spinal manipulation for subacute low back pain.
Serious
adverse events following lumbar spinal manipulation (such as worsening
lumbar disc herniation or cauda equina syndrome) are rare. The risk of a
serious adverse event, including data from observational studies, has
been estimated at less than one per one million patient visits. One systematic review found no serious complications reported in over 70 controlled clinical trials.
Such low rates of adverse events are likely to be contingent on
adherence to recommendations to avoid lumbar spinal manipulation in
patients with progressive or severe neurologic deficits.
Acupuncture — Acupuncture
is an intervention consisting of the insertion of needles at specific
predetermined acupuncture points. Evidence on the efficacy of
acupuncture versus sham acupuncture is inconsistent. Two systematic
reviews found acupuncture moderately more effective than no treatment
for short-term (<three months) pain relief and improvement in
function, and more effective than sham acupuncture for pain relief, but
not for improvement in function.
However, two well-blinded trials not included in the systematic reviews
found no difference between acupuncture and sham acupuncture for either
pain or function.
It is unclear if the effectiveness of sham acupuncture derives from
some attribute of superficial needling or is solely a placebo effect.
Acupuncture is likely to be most beneficial in patients who have high
expectations of benefit.

Massage — Interpretation
of studies to evaluate the effectiveness of massage therapy in chronic
low back pain is hampered by differences in the comparator
interventions, types of massage, and duration and frequency of massage
sessions. A systematic review found that massage was moderately superior
to joint mobilization, relaxation therapy, physical therapy,
acupuncture, sham laser, and self-care education.
The review concluded that massage might be beneficial for subacute and
chronic nonspecific low back pain, especially in combination with
exercise and education.
Although subsequent randomized trials
have confirmed the short-term benefits of massage therapy, long-term
benefits in low back pain have not been established.
One large randomized trial in 579 patients with chronic or recurrent
low back pain found that six sessions of massage therapy, with or
without a minimal exercise intervention, reduced disability and pain at
three months compared to usual care, but benefits were not sustained at
12 months.
Six sessions of massage were similarly effective compared to six
sessions of the Alexander technique. Another trial in 401 patients with
chronic nonspecific low back pain found that 10 sessions of massage
therapy reduced disability and pain at 10 weeks compared to usual care. The benefits waned over time with no clinically meaningful difference at 12 month follow-up.
PSYCHOLOGICAL AND MULTIDISCIPLINARY INTERVENTIONS
Cognitive behavioral therapy — A
variety of psychological approaches to patients with chronic low back
pain have been evaluated. A systematic review found cognitive-behavioral
therapy superior to wait list control for short-term pain relief,
though there were no differences in function. Results were less conclusive for other types of psychological intervention.
In a subsequent, 12-month randomized trial in patients with subacute or
chronic low back pain, those randomly assigned to group cognitive
behavioral therapy reported less pain and disability compared to no
further treatment.
Interdisciplinary rehabilitation — Interdisciplinary,
or multidisciplinary, therapy combines physical, vocational, and
behavioral components provided by multiple health care professionals.
Intensity and content of interdisciplinary therapy vary widely.
Systematic reviews found intensive interdisciplinary therapy more
effective than non-interdisciplinary rehabilitation for both chronic and
subacute low back pain.
Functional restoration — Functional
restoration, also known as work hardening or work conditioning,
involves simulated or actual work tests in a supervised environment to
improve strength, endurance, flexibility, and fitness for injured
workers.

PHYSICAL MODALITIES — A large number of physical modalities, in addition to the physical treatments already discussed have been used in patients with chronic low back pain. For most of
these modalities, there is little evidence of benefit from randomized
controlled studies, although patient expectations of benefit and placebo effects may play a role in their therapeutic value.
Interferential therapy — Interferential
therapy is the superficial application of a medium frequency
alternating current, modulated to produce low frequencies up to 150 Hz.
There is no convincing evidence from three trials that interferential
therapy is effective for chronic low back pain.
Low-level laser therapy — Low-level
laser therapy (LLLT), used by some physical therapists, is provided as a
single wavelength of light, between 632 and 904 nm, directed at the
area of discomfort. For chronic low back pain or back pain of
unspecified duration, four trials found laser therapy superior to sham
therapy for pain relief and improvement in function up to one year
following treatment. However, another trial found no difference between laser and sham in patients also receiving exercise. Another trial found no differences between laser, exercise, and the combination of laser plus exercise.

A
systematic review found some evidence of short-term benefit in relief
of low back pain, compared to sham therapy, but protocols for treatment
dosage, duration, and wavelength were inconsistent. The review concluded that data were insufficient to draw conclusions regarding effectiveness.
Ultrasound — Despite
being widely used for the treatment of many musculoskeletal pain
syndromes, few studies have evaluated ultrasound. It is usually
performed in combination with other physical therapy modalities, and its
beneficial effect is thought to be due to heating of deep tissues. For
chronic low back pain, two small (n = 10 and n = 36) trials reported
inconsistent results for ultrasound versus sham ultrasound, with the
larger trial reporting no differences. A systematic review concluded that ultrasound is ineffective in the treatment of chronic low back pain.
Short-wave diathermy — Shortwave
diathermy is the elevation of the temperature of deep tissues by
application of shortwave electromagnetic radiation with a frequency
range from 10 to 100 MHz. Two trials found no differences between
short-wave diathermy and sham diathermy manipulation for chronic low
back pain.
Traction — Traction
involves drawing or pulling in order to stretch the lumbar spine. A
variety of methods are used and typically involve a harness around the
lower rib cage and around the iliac crest, the pulling action performed
via free weights and a pulley, motorized equipment, inversion
techniques, or an overhead harness.
For mixed duration low back
pain with or without sciatica, a systematic review found no convincing
evidence from nine trials that continuous or intermittent traction is
more effective than placebo, sham, or no treatment.
Although autotraction was more effective than placebo, sham, or no
treatment in patients with sciatica, it was only evaluated in two trials
with methodological shortcomings.
Transcutaneous electrical nerve stimulation — Transcutaneous
electrical nerve stimulation (TENS) refers to the use of a small
battery-operated device to provide continuous electrical impulses via
surface electrodes, with the goal of providing symptomatic relief by
modifying pain perception. A systematic review included one small (n = 30) trial that found transcutaneous electrical nerve stimulation superior to placebo, but a larger (n = 145), well-blinded trial found no differences between TENS and sham TENS on any measured outcome.
Percutaneous electrical nerve stimulation — Percutaneous
electrical nerve stimulation (PENS) involves insertion of
acupuncture-like needles and applying low-level electrical stimulation.
The insertion points target dermatomal levels for local pathology,
rather than acupuncture points.
Although several trials found PENS
moderately to substantially superior to sham PENS for pain relief,
effects on function were inconsistent, all trials had methodological
shortcomings, and some trials only measured outcomes at the end of a
two-week course of treatment.
PENS is not currently widely available in the US.
OPTIMIZING THERAPY — There
are no trials evaluating optimal sequencing of therapies, and there is
no evidence that care directed by one spine provider specialty is
superior to other specialties or primary care providers. Decision tools
and other methods for individualizing therapy are in early stages of
development, and may not be practical for use in primary care settings.
Patient
expectations of benefit from a treatment should be taken into
consideration when choosing interventions, as they appear to influence
outcomes. Other factors to consider when choosing among therapies
include cost, convenience, and availability of skilled providers for
specific therapies. Clinicians should avoid interventions not proven
effective, as a number of non-pharmacologic therapies are supported by
at least fair evidence of moderate benefits.
PREVENTION — There are insufficient data to recommend the use of specific interventions for primary prevention of low back pain.
Primary prevention is a challenge due to the limited inability to
predict a person's likelihood of developing low back pain. However,
exercise therapy may have a role in secondary prevention, particularly
for those predisposed to having recurrent low back pain.



REFERÊNCIA: UpToDate - Approach to the diagnosis and evaluation of low back pain in adults


Subacute and chronic low back pain: Pharmacologic and noninterventional treatment