Acute low back pain
Recommendations
ACP2017Grade Strong recommendation
Acute or subacute low back pain usually improves regardless of treatment. Start with nondrug therapy: superficial heat (moderate-quality evidence), massage, acupuncture, or spinal manipulation. If medication is wanted, use an NSAID or a skeletal muscle relaxant. ACP now lists this 2017 guideline as inactive (over 5 years old) but has not replaced it.
Verify at ACP (opens in a new tab)ACR (Appropriateness Criteria)2021
Uncomplicated acute low back pain, with or without radiculopathy, does not need imaging. Consider imaging only after about 6 weeks of medical management and physical therapy with little or no improvement, or sooner for red flags suggesting cauda equina syndrome, cancer, fracture, or infection.
Verify at ACR (Appropriateness Criteria) (opens in a new tab)CDC2022Grade Category B, evidence type 3
Nonopioid therapies are at least as effective as opioids for many acute pain conditions, including low back pain. Maximize nondrug and nonopioid drug options; consider an opioid only if benefits are expected to outweigh risks, and if used, prescribe immediate-release, as needed, and no more than the expected duration of pain severe enough to need it.
Verify at CDC (opens in a new tab)Who this applies to
- Acute (under 4 weeks) and subacute (4 to 12 weeks) low back pain without red flags: most people improve substantially within weeks whatever is done. The job is to avoid harm and unnecessary testing (ACP 2017).
- Red flags that change the pathway: cauda equina signs (urinary retention, saddle anesthesia, bilateral leg weakness); progressive or severe neurologic deficit; a history of cancer; fever, injection drug use or a recent spinal procedure; significant trauma or fragility-fracture risk from age, osteoporosis or steroids.
How it is done in practice
- No imaging in the first 6 weeks without red flags (ACR Appropriateness Criteria 2021; the same advice was on the former Choosing Wisely lists from AAFP, ACR and NASS). Early MRI does not improve outcomes and leads to more procedures.
- First line for acute and subacute pain: stay active, superficial heat, massage, acupuncture or spinal manipulation. If medication is needed: an NSAID or a skeletal muscle relaxant. Acetaminophen was not found effective for acute back pain.
- Chronic pain (over 12 weeks): exercise, multidisciplinary rehabilitation, acupuncture, mindfulness-based stress reduction, tai chi, yoga, progressive relaxation, cognitive behavioral therapy or spinal manipulation first. Then NSAIDs; second line tramadol or duloxetine; opioids only when those fail and after a frank discussion of risk.
- No bed rest. Return to work with modified duties beats waiting for the pain to end.
- Systemic steroids are not recommended for back pain without radiculopathy.
What changed recently
ACP 2017 put non-drug therapy ahead of medication for every duration of back pain and removed acetaminophen as a first choice. ACP now lists the 2017 guideline as inactive because of its age but has not replaced it. The no-imaging-under-6-weeks rule is carried by the ACR Appropriateness Criteria (2021), since the Choosing Wisely lists are no longer maintained.
Points that matter in clinic
- Sciatica with a stable deficit can be managed conservatively for 6 weeks. Progressive weakness or cauda equina signs are an emergency.
- Explain that pain does not equal damage and that most people are much better within 6 weeks. That sentence, delivered with confidence, is treatment.
- Screen for yellow flags (fear-avoidance, low mood, job dissatisfaction) with the STarT Back tool; they predict chronic pain better than any image.