Malady Wise

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Back Pain

Maladywise

SUMMARY: Acute lower back pain in adults overview.

Fact Sheets

Incidence

80% of adults have lower back pain at some point in their life.

Acute = < 4 weeks

Subacute = 4 to 12 weeks

Chronic = > 12 weeks

Risk Factors

Smoking

Obesity

Age

Female Sex

Physically strenuous work

Sedentery work

Psychologically strenuous work

Lower education

Worker’s Compensation claims

Job Dissatisfaction

Psychological factors such as somatisation disorder, anxiety and depression.

Diagnosis

85% of patients have non-specific back pain. Most are musculo-skeletal. Most improve within a few weeks.

Serious problems account for 1% of patients and include

  • Spinal cord compression

  • Metastatic cancer

  • Spinal epidural abscess

  • Vertebral Osteomyelitis

Less serious problems account for about 10% of patients. 4% of these have a symptomatic disc herniation or spinal stenosis.

  • Vertebral compression fracture

  • Radiculopathy

  • Spinal stenosis

  • Axial Spondyloarthritis

  • Osteoarthritis

  • Scoliosis

  • Piriformis Syndrome

  • Sacroiliac joint dysfunction

History

Location, duration and severity of pain.

Weight loss, fever, night sweats, history of cancer.

Precipitating events

Therapies tried

Neurological changes such as weakness, falls, gait instability, numbness, bowel or bladder changes.

Stability or worsening or symptoms.

Recent infections.

Medication use including corticosteroids.

Recent spinal procedures.

Evaluate social or psychological distress.

Features suggestive of underlying systemic disease include:

History of cancer

Age > 50

Weight loss

Pain > 4 weeks

Nocturnal pain

Unresponsive to previous therapies

Injection drug use

Recent bacterial infection

Recent spinal procedure

Exam

Purpose of exam is to identify features that suggest further evaluation is necessary.

Inspection for scoliosis, hyper-kyphosis

Palpation or percussion for vertebral tenderness, soft tissue tenderness.

Neurological exam including reflexes, strength, sensation and gait.

Straight Leg Raise to identify radiculopathy

Non-organic / Waddell’s signs

  • Overreaction during physical examination

  • Superficial or widespread tenderness

  • Inconsistent supine and seated (distracted) straight leg raise test

  • Unexplainable neurologic deficits

  • Pain on simulated axial load (top of head pressure)

Other exam based on history

Bladder U/S if urinary incontinence

Cancer screening if suggestive

Hip exam

Peripheral Vascular Disease

Blood Tests

Not routinely necessary unless history and exam suspicious for a cause.

ESR/CRP may be used if suspicious for cancer or axial spondyloarthritis.

Testing for multiple myeloma such as Immunoglobulins, SPEP, Serum free light chains etc.

Imaging

A 2009 systematic review and meta-analysis compared immediate imaging (MRI / CT / XRAY) with usual care for acute and subacute back pain (in the absense of red flags for cancer or infection).

There was no difference in short-term or long-term outcomes for measures of patient pain or function.

One study of US Veterans showed patients with nonspecific back pain without red flags who had an early MRI within 6 weeks had a greater likelihood of surgery (1.5% vs 0.1%), treatment with opioids (35% vs 29%) and greater overall at one year.

Also: Disc herniation on MRI are seen in 22 to 67% of patients without back pain. Spinal stenosis in 20% of patients over 65 without symptoms.

Indications for Imaging

Reserve imaging for patients with severe or progressive neurological deficits or when serious underlying pathology are suspected based on history and exam.

Indications include:

Rapid or severe neurological deficit

Radiculopathy if suspected to be due to malignancy

MRI if radiculopathy ongoing despite > 4 to 6 of conservative therapy

Moderate to high clinical suspicion for infection or cancer

Lower concerns for infection or cancer but elevated ESR/CRP

XRAY SIJ if concern for axial spondylo-arthritis not responding to 4 to 6 weeks of therapy

Treatment

The goal of the initial treatment of non-specific acute lower back pain is symptom relief

Heat - Moderate evidence that a heat wrap may reduce pain and disability for patients with pain of fewer than three months duration, but the benefit was small and short-lived.

Massage - No evidence that massages offer clinical benefit.

Acupuncture - Limited evidence for benefit in acute back pain but it is safe with few side effects.

Spinal manipulation - Moderate evidence for some improvement in pain and function. Minor transient side effects of pain, stiffness and headache in 50-67% of patients. Serious adverse effects are rare.

Exercise and Physical Therapy - Generally not recommended for acute back pain. Limited evidence for the efficacy of exercise therapy over other conservative treatments in acute back pain. Most useful for patients at high risk of developing chronic back pain.

Therapies with no benefit

Cold - No evidence for benefit from 2006 systematic review

Muscle energy technique - No evidence of benefit from 2015 systematic review

Traction - No evidence of benefit from 2013 systematic review

Lumbar supports - No evidence

Yoga - No quality studies on acute back pain. More used for chronic back pain.

Paraspinal injections - No quality evidence for acute nonspecific back pain.

Pharmacology

Initial therapy

2 to 4 weeks of a nonsteroidal anti-inflammatory drug (NSAID). Decrease dose as tolerated. Side effects GIT upset.

  • Ibuprofen 400mg four times daily

  • Naproxen 250mg or 500mg twice daily

Limited evidence for Paracetamol. 2016 Cochrane review showed no benefit.

Second-line therapy

Consider a non-benzodiazepine muscle relaxant such as Baclofen or Orphenadrine. 2003 systematic review showed short-term benefits. Adverse effects are sedation and dizziness.

Opioids

Limited benefits when added to NSAID therapy. If used, the duration should be brief, ideally limited to three days maximum. Adverse effects include sedation, nausea, constipation, respiratory depression and drug misuse.

Medications with limited or no evidence

  • Antidepressants

  • Steroids such as Prednisolone

  • Antiepileptics

  • Topical Capsaicin - low-quality evidence for some immediate relief.

  • Herbal therapies - Limited evidence for use.


References

Evaluation of lower back pain - UpToDate

Treatment of acute low back pain - UpToDate

Low back pain: Can we mitigate the inadvertent psycho-behavioural harms of spinal imaging? - RACGP

Non-radicular low back pain: Assessment and evidence-based treatment - AJGP