Non-Specific Low Back Pain

I thought that this Review article, by Balague et al (2012), was a wonderful outline of where we are at with regards to Non-Specific Low Back Pain. I would recommend those interested read the article in detail as obviously the vast majority of information below is cited by the authors.

General Summary:

• The lifetime prevalence of low back pain is reported to be as high as 84%, and the prevalence of chronic low back pain is about 23%, with 11-12% of the population being disabled by low back pain.
• Mechanical factors, such as lifting and carrying, probably do not have a major pathogenic role, but genetic constitution is important.
• The use of clinical imaging for diagnosis should be restricted.
• The mechanism of action of many treatments is unclear, and effect sizes of most treatments are low.
• Both patient preferences and clinical evidence should be taken into account for pain management, but generally self-management, with appropriate support, is recommended.
• Surgery and overtreatment should be avoided.

MRI findings:

• A systematic review with meta-analysis concluded that, at the individual level, none of the lesions (with the exception of Modic signs) identified by MRI could be established as the cause of low back pain because such MRI abnormalities are very common in:
  • people who are asymptomatic.
  • do not coincide with the development of low back pain and;
  • do not predict the response to evidence-based therapy for non-specific low back pain.

Mechanical factors:

• Eight systematic reviews concluded that it was unlikely that the following factors were independently causative of low back pain:
  • Occupational sitting
  • Awkward postures
  • Standing
  • Walking
  • Manual handling or assisting patients
  • Pushing or pulling
  • Bending and twisting
  • Lifting or carrying

Classification of Back Pain:

• The Red flags consistently reported in the published work include:
  • Weight loss
  • Previous history of cancer
  • Night pain
  • Age more than 50 years
  • Violent trauma
  • Fever
  • Saddle anaesthesia
  • Difficulty with micturition
  • Intravenous drug misuse
  • Progressive neurological disturbances
  • Systemic steroids.
• Henschke and colleagues (see my Red Flag Post) showed that, using 25 red flag questions in a primary care setting, 80% of patients (942 of 1172) had at least one red flag; this finding contrasted with a prevalence of serious disease of 0·9% (11 of 1172).
• Other research would suggest that if a thorough assessment has been undertaken, and if there are no red flags, one can be 99% confident that serious spinal disease has not been missed.
• Four features are significantly associated with vertebral fracture:
  • Female sex
  • Age >70 years
  • Substantial trauma
  • Prolonged use of corticoids
• For malignancy the following combination has been reported to have a perfect sensitivity and negative likelihood ratio, but only moderate specificity and positive likelihood ratio:
  • Age 50 years or older
  • History of cancer
  • Unexplained weight loss
  • Failure of conservative therapy.
• Once serious disease has been ruled out, the next priority is to identify patients with radicular pain.
• All other cases are classified as non-specific and the patient should be assessed for the severity of symptoms and functional limitations, and for risk factors for chronicity.
• Dermatomal radiation, more pain on coughing, sneezing or straining, positive straight leg raising, and crossed straight leg raising can be used to predict nerve root compression on MRI.
• Most patients seeking surgical treatment for lumbar stenosis, for example, do not have positive physical examination findings and have subjective symptoms only, such as pain during walking.