Management of Chronic Unilateral Low Back Pain That Improves with Movement
Begin with nonpharmacologic therapy as first-line treatment, specifically exercise therapy, yoga, tai chi, or spinal manipulation, since pain that improves with movement indicates a mechanical etiology that responds best to activity-based interventions. 1
Initial Nonpharmacologic Approach (First-Line)
The American College of Physicians issues a strong recommendation for nonpharmacologic therapy as the primary treatment for chronic low back pain (>12 weeks duration). 1 Your patient's symptom pattern—pain improving with movement—is the classic presentation of mechanical low back pain that responds optimally to activity-based treatments. 2
Specific evidence-based options include:
Exercise therapy: Provides moderate pain relief (approximately 10 points on a 100-point scale) and functional improvement, with best outcomes when using individualized, supervised programs incorporating stretching and strengthening. 1
Yoga: Viniyoga or Iyengar styles demonstrate moderate superiority over self-care education, with sustained benefits at 26 weeks and decreased medication use. 1
Tai chi: Supported by moderate-quality evidence for chronic low back pain management. 1
Spinal manipulation: Low-quality evidence supports its use, but it remains a guideline-recommended option. 1
Motor control exercises: Moderate-quality evidence supports their effectiveness. 1
The key principle is staying active and avoiding bed rest, as activity promotes recovery while rest leads to deconditioning and potentially worsens symptoms. 3, 4
Pharmacologic Therapy (Second-Line)
If nonpharmacologic therapy provides inadequate response after a reasonable trial (typically 4-12 weeks), add pharmacologic treatment:
First-line medication:
- NSAIDs (naproxen or ibuprofen): Most effective pharmacologic option with moderate-quality evidence, providing superior pain relief compared to other oral medications. 1, 3, 5
Second-line medications (if NSAIDs inadequate or contraindicated):
Duloxetine (30-60 mg daily): Specifically recommended by the American College of Physicians as second-line therapy, particularly beneficial if neuropathic pain component exists. 1, 3, 6
Tramadol: Alternative second-line option per ACP guidelines. 1
Avoid or use with extreme caution:
- Acetaminophen has inconclusive evidence and is less effective than NSAIDs. 5
- Muscle relaxants, benzodiazepines, and most antidepressants (except duloxetine) lack strong evidence. 5
- Opioids should only be considered after documented failure of all above treatments, and only when benefits clearly outweigh risks after thorough discussion with the patient. 1, 3
What NOT to Do (Critical Pitfalls)
Strongly avoid interventional procedures for axial (non-radicular) low back pain:
The 2025 BMJ guidelines issue strong recommendations AGAINST epidural injections, facet joint injections, and radiofrequency ablation for chronic axial spine pain, as these do not improve morbidity or quality of life. 7, 3, 6
These procedures are only potentially appropriate for radicular pain (leg pain with nerve root involvement), which your patient does not have. 1
Do not routinely obtain imaging unless red flags are present (progressive neurological deficits, cauda equina symptoms, suspected infection/malignancy, or significant trauma). 3, 5 Imaging findings in nonspecific low back pain are often incidental and do not improve outcomes. 3
Addressing the Unilateral Component
The unilateral nature of the pain does not change the treatment algorithm, as most mechanical low back pain presents asymmetrically. 8 The fact that movement improves symptoms strongly suggests myofascial or facet-mediated pain rather than discogenic or radicular pathology. 8, 2
Cognitive-Behavioral Approaches
Consider adding cognitive-behavioral therapy or mindfulness-based stress reduction as adjuncts, particularly if psychological yellow flags are present (fear-avoidance behaviors, catastrophizing, depression). 1, 6 These interventions have moderate-quality evidence for chronic low back pain and can prevent disability. 1, 4
When to Refer
Refer to multidisciplinary pain management if pain persists despite optimized nonpharmacologic and pharmacologic therapy over 3-6 months. 3 Immediate specialist consultation is required only for red flags: progressive neurological deficits, cauda equina syndrome, suspected infection, or malignancy. 3