What are the initial treatment recommendations for a patient with acute lower back pain after straining?

Initial Treatment of Acute Lower Back Pain After Straining

For acute lower back pain after straining, stay active within pain limits, apply superficial heat, and use NSAIDs or acetaminophen for symptom relief—avoid bed rest and routine imaging unless red flags are present. 1

Immediate Management (First 48-72 Hours)

Activity Modification

• Maintain normal activity within pain tolerance rather than strict bed rest, as staying active reduces disability and improves outcomes 2, 1
• Return to work and usual activities as soon as tolerable, even if some discomfort persists 1
• If severe pain necessitates brief rest, limit it to 1-2 days maximum and resume activity promptly 2

Non-Pharmacologic First-Line Treatment

• Apply superficial heat using heating pads or heated blankets for short-term pain relief, effective within 4-5 days 1, 3
• Provide reassurance that 90% of acute low back pain episodes resolve within 4-6 weeks regardless of treatment 1, 4
• Avoid passive modalities like ultrasound, TENS, or traction as standalone treatments 3

Pharmacologic Options (If Needed)

• Start with acetaminophen up to 4g daily for mild-to-moderate pain, which has a favorable safety profile and low cost 1, 5
• If acetaminophen is insufficient, use NSAIDs such as ibuprofen 400mg every 4-6 hours (maximum 3200mg daily) for superior pain relief 1, 5
• Consider skeletal muscle relaxants (cyclobenzaprine, tizanidine, or metaxalone) for short-term relief if muscle spasm is prominent 2, 3
• Avoid systemic corticosteroids entirely, as they are no more effective than placebo 2
• Avoid opioids for initial management due to abuse potential and lack of superior efficacy 1

When to Add Spinal Manipulation

• If symptoms persist beyond 1-2 weeks, consider spinal manipulation by appropriately trained providers (chiropractor, osteopath, or physical therapist), which provides small to moderate short-term benefits for acute low back pain 2, 1
• Spinal manipulation is most effective when combined with advice to stay active 3

Red Flags Requiring Immediate Evaluation

Obtain urgent imaging (MRI preferred over CT) and specialist consultation if any of the following are present 1:

• Cauda equina syndrome (saddle anesthesia, bowel/bladder dysfunction, bilateral leg weakness)
• Progressive or severe neurologic deficits
• History of cancer with new back pain
• Unexplained weight loss or fever suggesting infection or malignancy
• Significant trauma (or minor trauma in elderly/osteoporotic patients)
• Midline tenderness with fever or recent infection suggesting vertebral osteomyelitis

What NOT to Do

• Do not order routine imaging (X-ray, MRI, or CT) for uncomplicated acute low back pain, as it exposes patients to unnecessary radiation without clinical benefit and may lead to unnecessary interventions 1
• Do not prescribe prolonged bed rest, which leads to deconditioning and worse outcomes 1, 3
• Do not start supervised exercise therapy or home exercise programs in the acute phase (<4 weeks), as they are not effective for acute low back pain 2
• Avoid extended courses of any medication unless clear continued benefit without adverse events 2

Follow-Up Strategy

• Reassess at 1 month if symptoms persist without improvement 1
• Consider earlier reevaluation (2-3 weeks) for patients over 65 years, those with signs of radiculopathy (leg pain below the knee, numbness, weakness), or worsening symptoms 1
• If no improvement after 4-6 weeks of conservative management, consider plain radiography as initial imaging option before advancing to MRI 1
• At the 4-6 week mark, if still symptomatic, transition to treatments effective for subacute/chronic pain: exercise therapy, acupuncture, massage, or cognitive-behavioral therapy 2

Common Pitfalls to Avoid

• Failing to assess for psychosocial "yellow flags" (depression, catastrophizing, fear-avoidance beliefs, job dissatisfaction) that predict progression to chronic disabling pain 1
• Overreliance on imaging findings without clinical correlation—many asymptomatic people have disc bulges on MRI 3
• Using NSAIDs without assessing cardiovascular and gastrointestinal risk factors, or failing to use the lowest effective dose for shortest duration 3, 5
• Referring for interventional procedures (epidural injections, radiofrequency ablation) in patients with axial low back pain without radicular symptoms, as these do not improve quality of life 6