One-liner#

Adult/geriatric approach to acute vs chronic low back pain: separate mechanical vs radicular vs red-flag etiologies, and set an outpatient-safe initial plan.

Quick nav#

Red flags / send to ED#

  • Suspected cauda equina: urinary retention/overflow incontinence, saddle anesthesia, new bilateral leg weakness, rapidly progressive neurologic deficits
  • Suspected spinal infection: fever/systemic illness plus focal severe back pain (esp. IVDU, immunosuppression, recent bacteremia/procedure)
  • Suspected fracture/instability: major trauma, or minor trauma with osteoporosis/older age, chronic steroid use
  • Suspected malignancy: known cancer, unexplained weight loss, pain at rest/night, failure to improve as expected
  • Suspected AAA or other vascular catastrophe: back/abdominal pain with hypotension/syncope, pulsatile mass, severe constant pain
  • Any new objective focal neuro deficit that is progressive (motor weakness > sensory symptoms)

Key history#

  • Time course: acute (<6 weeks) vs subacute/chronic; sudden vs gradual; first episode vs recurrent
  • Trigger: lifting/twist, fall/trauma, prolonged sitting, new activity; occupational exposures
  • Location/radiation: midline vs paraspinal vs buttock; radiation below knee; unilateral vs bilateral
  • Neurologic symptoms: weakness, numbness, “pins/needles,” foot drop, gait change
  • Bowel/bladder/saddle symptoms (screen every time)
  • Systemic/infection risk: fever, chills, recent infection, IVDU, immunosuppression, diabetes, recent spinal injection/surgery
  • Cancer/fracture risk: history of cancer, osteoporosis, chronic steroids, unexplained weight loss, night pain
  • Functional impact: sleep, walking tolerance, work; what the patient is avoiding because of pain
  • Prior care: prior imaging, PT, injections, surgery; response to NSAIDs/heat/activity modification

Focused exam#

  • Vitals, general appearance, fever
  • Gait (antalgic, foot drop), sit-to-stand; ability to heel/toe walk
  • Lumbar ROM (pain with flexion/extension); palpation for focal midline tenderness (fracture concern)
  • Neuro screen (compare sides): strength (hip flexion, knee extension, ankle dorsiflexion, great toe extension, plantarflexion), sensation, reflexes
  • Straight-leg raise / crossed SLR (radicular pain); femoral stretch test if anterior thigh symptoms
  • Hip exam if pain is “back” but really hip (ROM, FABER/FADIR as appropriate)
  • If cauda equina suspected: perineal sensation, anal wink/tone (urgent evaluation)

Differential (quick pattern recognition)#

Common/likely (outpatient)#

DiagnosisKeywords patients useKey cluesFocused exam cluesInitial next step
Mechanical low back pain (strain/sprain)“Pulled muscle,” “tight/spasms,” worse with bending/liftingAfter activity, improves with movement; no true neuro symptomsParaspinal tenderness; neuro exam normalActivity as tolerated, heat, NSAID/topical, home exercises/PT
Lumbar radiculopathy (disc herniation)“Sciatica,” “shooting,” “burning,” “electric,” numbness/tinglingRadiates below knee in dermatomal pattern; worse with cough/sneeze+SLR; sensory/reflex changes; possible motor weaknessConservative care if stable; urgent imaging if progressive motor deficit
Lumbar spinal stenosis“Legs get heavy,” “can’t walk far,” “better leaning forward”Older; neurogenic claudication; better with sitting/flexionOften normal at rest; symptoms with walking/extensionFlexion-based PT, activity pacing; imaging if persistent/consider procedures
Facet arthropathy“Stiff,” “worse standing,” “worse extension”Older; worse with extension/rotationPain with extension/rotation; neuro exam normalNSAIDs/topicals, PT; consider injections/referral if refractory
SI joint pain“Pain near one dimple,” buttock painWorse with prolonged standing/transitionsTender over SI; provocative tests may reproduce painPT/core/glute strengthening; consider injection if persistent
Hip OA referred as back pain“Groin pain,” “can’t put on socks”Pain with weight-bearing; limited hip ROMDecreased hip internal rotation; pain with hip ROMHip-focused evaluation and management; consider hip imaging

Can’t-miss / urgent#

DiagnosisKeywords patients useKey cluesFocused exam cluesInitial next step
Cauda equina“Can’t pee,” “numb when I wipe,” bilateral symptomsUrinary retention/incontinence, saddle anesthesia, bilateral weaknessObjective weakness, decreased perineal sensationED now; emergent MRI/neurosurgery
Spinal epidural abscess / discitis“Worst back pain,” “feels sick”Fever or recent bacteremia; IVDU/immunosuppressionFocal severe tenderness; neuro may be normal earlyED now; ESR/CRP, MRI, blood cultures
Vertebral compression fracture“Sudden pain after minor strain,” “can’t stand up”Older/osteoporosis/steroids; focal midline painMidline tenderness; kyphosisSame-day imaging; pain control; consider osteoporosis workup
Malignancy/metastasis“Pain at night,” “won’t go away”Cancer history, weight loss; progressive symptomsPossible neuro deficits; midline tendernessUrgent evaluation; MRI if suspicion high
AAA“Back and belly pain,” syncopeVascular risk; hypotension; severe constant painPulsatile abdominal mass (often absent)ED now; emergent imaging

Workup#

  • No imaging for uncomplicated acute low back pain (<6 weeks) without red flags or objective neuro deficit.
  • If symptoms are clearly radicular but stable (no progressive weakness), avoid early MRI; treat conservatively and image if it will change management (e.g., procedure/surgery consideration).
  • X-ray: suspected fracture; older/osteoporosis with focal midline tenderness; persistent pain not improving as expected (context-dependent).
  • MRI (urgent): progressive motor deficit, cauda equina concern, suspected infection/malignancy.
  • MRI (non-urgent): persistent radicular symptoms not improving with conservative care and considering injections/surgery.
  • Labs (when indicated): CBC + ESR/CRP if infection/malignancy concern; UA if urinary symptoms suggest stone/pyelo rather than spine.

When NOT to image:

  • Acute mechanical low back pain <6 weeks without red flags
  • Chronic low back pain that has been stable and previously evaluated
  • “Just to see what’s there”—degenerative findings are ubiquitous and often not clinically relevant

Initial management#

  • Reassure and set expectations: most mechanical/radicular episodes improve over weeks.
  • Encourage activity as tolerated; avoid prolonged bed rest; consider “relative rest” from provoking movements.
  • Symptom relief options (choose based on comorbidities/contraindications; verify local protocol/formulary)—see medication tables below.
  • Start home exercise plan and/or refer to PT early if function-limiting or recurrent.
  • Avoid escalation to opioids except rare, carefully selected cases; reassess diagnosis if pain is severe and out of proportion.

Analgesic options#

DrugDoseContraindicationsMonitoringCostNotes
Acetaminophen650–1000 mg q6–8h; max 3 g/day (2 g/day if liver disease/alcohol)Severe hepatic impairment; chronic alcohol use (reduce max dose)LFTs if prolonged use or hepatic risk$First-line adjunct; limited efficacy alone for back pain but safe add-on
Ibuprofen400–600 mg q6–8h with food; max 2400 mg/dayCKD (eGFR <30), active GI bleed/ulcer, uncontrolled HTN, HF, anticoagulationCr, BP if prolonged use; GI symptoms$Effective for inflammatory/mechanical pain; limit to 7–10 days if possible
Naproxen250–500 mg q12h; max 1000 mg/daySame as ibuprofenSame as ibuprofen$Longer half-life; convenient BID dosing
Diclofenac gel 1%Apply 4 g to affected area QID; max 16 g/day per jointAvoid on broken skin; caution if systemic NSAID contraindicationsMinimal systemic absorption$$Good for localized pain; lower GI/renal risk than oral NSAIDs
Meloxicam7.5–15 mg dailySame as ibuprofen; avoid if sulfonamide allergySame as ibuprofen$Once-daily dosing; COX-2 preferential (slightly lower GI risk)

Muscle relaxants (short-term use for prominent spasm)#

DrugDoseContraindicationsMonitoringCostNotes
Cyclobenzaprine5–10 mg TID or 5 mg at bedtime; max 30 mg/dayArrhythmia, recent MI, hyperthyroidism, MAOIs; avoid in elderly (Beers)Sedation, anticholinergic effects$Most studied; highly sedating—use lowest dose at bedtime; limit to 1–2 weeks
Methocarbamol750–1500 mg TID–QID; max 6 g/dayRenal impairment (use caution)Sedation$Less sedating than cyclobenzaprine; reasonable alternative
Tizanidine2–4 mg q6–8h; max 36 mg/dayHepatic impairment; concurrent CYP1A2 inhibitors (cipro, fluvoxamine)LFTs at baseline and periodically; sedation, hypotension$Alpha-2 agonist; can cause hypotension; useful if cyclobenzaprine not tolerated
Baclofen5 mg TID, titrate to 10–20 mg TID; max 80 mg/dayRenal impairment (renally cleared); abrupt withdrawal riskSedation; do not stop abruptly$Less anticholinergic; requires slow taper if used >2 weeks

When NOT to prescribe muscle relaxants:

  • Elderly patients (fall risk, anticholinergic burden)—if needed, use lowest dose at bedtime only
  • Concurrent sedatives, opioids, or alcohol use
  • Prolonged use (>2 weeks) without reassessment

Oral steroids for acute radiculopathy (controversial)#

DrugDoseContraindicationsMonitoringCostNotes
Prednisone40–60 mg daily × 5 days (no taper needed for short course)Uncontrolled DM, active infection, psychosis historyBlood glucose in diabetics$Evidence is mixed; may provide short-term pain relief but no long-term benefit; discuss with patient
Methylprednisolone dose pack4 mg tabs, tapered over 6 days per packageSame as prednisoneSame as prednisone$Convenient but lower total dose than prednisone burst; no evidence it’s better than prednisone

When to consider oral steroids:

  • Acute radiculopathy with significant pain limiting function
  • Patient prefers to try before considering injections/surgery
  • Short-term bridge while awaiting PT or specialist evaluation

When NOT to use oral steroids:

  • Mechanical back pain without radicular component (no benefit)
  • Uncontrolled diabetes (will spike glucose significantly)
  • Recurrent use (not a long-term strategy)
  • Chronic radiculopathy (no evidence of benefit)

Management by diagnosis#

Mechanical low back pain (strain/sprain)#

Education: Safe to stay active; brief flare-ups are common; “hurt ≠ harm” if no red flags.

Treatment:

  • Heat, topical/oral analgesics as appropriate (see tables above)
  • Early mobility: short, frequent walks; avoid bed rest
  • PT/home program: hip hinge mechanics, core/hip strengthening, graded return to lifting
  • Work/activity note: temporary restrictions can help patients stay active safely (avoid total inactivity)

Follow-up: 1–2 weeks if not improving or function-limiting; sooner if new neuro symptoms.

Lumbar radiculopathy (disc herniation)#

Education: Leg symptoms can take weeks to months to resolve; watch for progressive weakness.

Treatment:

  • Activity modification without immobilization; avoid prolonged sitting if it worsens symptoms
  • PT (often includes directional preference work, nerve glides, graded strengthening)
  • Analgesics as above; treat pain enough to maintain function
  • Consider gabapentinoids for neuropathic component if NSAIDs insufficient (see table below)
DrugDoseContraindicationsMonitoringCostNotes
Gabapentin100–300 mg at bedtime, titrate by 100–300 mg q3–7 days; target 300–600 mg TIDRenal impairment (reduce dose); sedation riskSedation, dizziness; Cr for dose adjustment$Start low, go slow; takes 2–4 weeks for effect; taper to discontinue
Pregabalin25–75 mg BID, titrate to 150–300 mg BIDRenal impairment (reduce dose); HF (edema risk)Sedation, edema, weight gain$$$Faster onset than gabapentin; Schedule V controlled substance
Duloxetine30 mg daily × 1 week, then 60 mg dailyHepatic impairment; concurrent MAOIs; uncontrolled glaucomaBP, mood; hepatic function if risk$$SNRI; also helps if comorbid depression/anxiety; avoid abrupt discontinuation

Referral: Consider spine referral if persistent disabling symptoms despite 6–8 weeks conservative care or if considering procedures.

Follow-up: 1–2 weeks if significant symptoms; urgent re-eval for new/worsening weakness, bowel/bladder symptoms.

Lumbar spinal stenosis (neurogenic claudication)#

Education: Symptoms often posture-dependent; flexion can be relieving; this is a chronic condition.

Treatment:

  • Flexion-based PT, pacing strategies, and walking aids as needed
  • Analgesics as above; gabapentinoids may help neurogenic symptoms
  • Consider imaging if symptoms persist and results would change management (e.g., injections/surgical discussion)

Referral: Consider when walking tolerance remains poor despite 6–8 weeks of rehab.

Follow-up: 4–6 weeks; earlier if rapid decline or objective deficits.

Vertebral compression fracture (suspected/confirmed)#

Education: Evaluate for osteoporosis and fall risk; set expectations for gradual improvement over 6–12 weeks.

Treatment:

  • Analgesia (acetaminophen preferred; NSAIDs short-term if needed; avoid muscle relaxants in elderly)
  • Short-term bracing in select cases; early mobilization
  • Assess/treat osteoporosis risk (DXA pathway, calcium/vitamin D status, fall-risk interventions) per local protocol
  • Consider referral based on severity or persistent functional limitation

Follow-up: Within 1 week; urgent escalation if neuro deficits or uncontrolled pain.

See also: Osteoporosis problem page for comprehensive bone health management.

Chronic low back pain (>12 weeks)#

Education: Chronic pain is complex; goal is function improvement, not necessarily pain elimination. Hurt ≠ harm.

Treatment:

  • Multimodal approach: PT (active rehab, not passive modalities), cognitive-behavioral strategies, sleep optimization
  • Avoid opioid escalation; if already on opioids, consider tapering with support
  • Consider duloxetine or low-dose TCA (amitriptyline 10–25 mg at bedtime) for central sensitization component
  • Address psychosocial factors: depression, anxiety, catastrophizing, work/disability issues
  • Injections (epidural, facet, SI joint) may provide temporary relief but are not curative; use as bridge to active rehab

When to refer:

  • Pain psychology/chronic pain program if significant functional impairment
  • PM&R or pain management for procedural options
  • Spine surgery only if clear structural pathology correlating with symptoms

What NOT to do:

  • Repeated imaging without new symptoms (degenerative findings are ubiquitous)
  • Escalating opioids for chronic non-cancer pain
  • Passive treatments only (massage, chiro, acupuncture) without active rehab component

Follow-up#

  • Typical: Reassess in 1–2 weeks for acute pain that limits function or is not clearly improving.
  • Re-evaluate sooner if pain rapidly worsens, new fever/systemic symptoms, new objective weakness, or new bowel/bladder changes.
  • If not improving by 4–6 weeks, reconsider the diagnosis (hip pathology, inflammatory disease, fracture) and escalate (PT adherence, imaging, referral).

Patient instructions#

  • Stay active as tolerated (short, frequent walks); avoid prolonged bed rest.
  • Use heat 15–20 minutes at a time for muscle spasm/tightness.
  • Consider over-the-counter pain options if safe for you (avoid NSAIDs if kidney disease, ulcers, blood thinners, etc.; avoid excess acetaminophen if liver disease).
  • Do the exercises your provider or physical therapist recommends.
  • Call or seek urgent care now for: trouble urinating, new bowel/bladder accidents, numbness in the groin/saddle area, new leg weakness, fever with worsening back pain, or severe pain after a fall.

Smartphrase snippets#

Acute mechanical LBP, reassurance: Acute low back pain without red flags; neuro exam intact. Discussed expected course (most improve within 2–4 weeks), activity as tolerated, home exercise/PT, analgesic options, and strict return precautions for weakness, numbness, or bowel/bladder changes.

Radiculopathy, conservative management: Lumbar radiculopathy with [dermatomal] symptoms; no progressive motor deficit. Plan: conservative management with activity modification, PT referral, and analgesics. Discussed that most disc herniations improve without surgery. Return precautions reviewed; will reassess in 2 weeks or sooner if worsening weakness.

Complaint pages#

Problem pages#

  • Osteoarthritis — chronic joint disease management including facet arthropathy
  • Osteoporosis — bone health, fracture prevention, and compression fracture management
  • Gout — if crystal arthropathy suspected in spine (rare but consider in polyarticular presentations)

Referral for persistent symptoms: Persistent low back pain with [radicular symptoms/functional limitation] despite [X weeks] conservative care. Referring to [spine/PM&R/pain management] for evaluation and consideration of [imaging/injections/surgical consultation]. Continue current management pending appointment.