Muscle relaxants are largely ineffective for low back pain

Muscle relaxant medications are largely ineffective for low back pain, although they are widely prescribed for this condition, suggests an analysis of recent evidence published by The BMJ today.

The findings prove it muscle relaxants can be reduced pain in the short term, but the effect is too small to be considered clinically significant and there is an increased risk of side effects.

But researchers stress that the certainty of the evidence is low and say it is high essays are urgent to resolve uncertainties about the use of these drugs for back pain.

Low back pain is a global public health problem and muscle relaxants (a wide class of drugs that include antispasmodics and non-benzodiazepine antispasmodics) are a commonly prescribed treatment.

For example, in 2020, revenue in England exceeded 1.3 million and in the US more than 30 million. However, worldwide, clinical practice guidelines offer conflicting recommendations for their use.

To address this, researchers in Australia investigated the efficacy, acceptability, and safety of muscle relaxants compared with placebo, routine care, or the absence of treatment in adults with nonspecific low back pain.

They reviewed and conducted a detailed analysis of the evidence from 31 randomized controlled trials that included more than 6,500 participants, published through February 2021.

The trials were of variable quality, but the researchers were able to assess the certainty of the evidence using the recognized GRADE system.

They set a difference of at least 10 points on a scale of 0 to 100 points for pain and disability to be the most clinically important effect, a threshold used in other low back pain studies.

Very low certainty tests showed that non-benzodiazepine antispasmodic drugs could reduce pain intensity at two weeks or less in patients with acute low back pain compared to controls. But this effect is small (less than eight points on a scale of 0 to 100 points) and does not meet common thresholds to be clinically significant.

There was little or no effect of non-benzodiazepine antispasmodics on pain intensity at 3–13 weeks or on disability at all follow-up times.

Evidence of low and very low certainty also showed that non-benzodiazepine antispasmodics could increase the risk of adverse events (usually dizziness, drowsiness, headache, and nausea) and may have little or no effect on discontinuation of treatment. compared to controls.

No trial evaluated the effect of muscle relaxants on long-term outcomes.

While this analysis was based on the best available evidence, researchers acknowledge some limitations and say the modest overall effect may still mean some, but not all, reap a worthwhile benefit.

However, they stress that the certainty of low to very low evidence does not allow for firm recommendations.

“We would encourage clinicians to discuss this uncertainty about the effectiveness and safety of muscle relaxants with patients, sharing information about the possibility of a benefit in reducing pain, but an increased risk of a non-serious adverse event. , to allow them to inform treatment decisions, “they write.

“Large, high-quality, placebo-controlled trials are urgently needed to resolve uncertainties about the efficacy and safety of muscle relaxants per back pain“, they conclude.