What investigations and potential diagnoses should be considered for a 55-year-old female (F) paramedic with sudden onset of left lower back lumbar spine pain after lifting a heavy bag, with decreased range of motion (ROM) and pain elicited with hip movement?

Diagnostic Approach for Acute Lower Back Pain with Hip Movement Limitations

For a 55-year-old female paramedic with sudden onset left lumbar pain after bending forward, with decreased hip range of motion, initial management should focus on conservative treatment without imaging unless red flags are present. 1, 2

Initial Diagnostic Considerations

Most Likely Diagnoses

• Nonspecific mechanical low back pain/muscle strain (most common)
• Possible lumbar disc herniation (especially if radicular symptoms develop)
• Facet joint syndrome
• Sacroiliac joint dysfunction

Red Flags to Assess

• Progressive neurological deficits (motor weakness, sensory changes)
• Bladder/bowel dysfunction (urinary retention has 90% sensitivity for cauda equina syndrome)
• History of cancer, unexplained weight loss
• Fever or signs of infection
• Severe trauma disproportionate to mechanism of injury
• Age >50 (modest risk factor for cancer, positive likelihood ratio 2.7) 1

Recommended Investigations

Initial Approach

• No imaging is recommended initially for mechanical back pain without red flags 1, 2
• Imaging should be delayed for at least 4-6 weeks unless red flags are present 2

When to Consider Imaging

1. If symptoms persist >6 weeks despite conservative management
2. If radicular symptoms develop (pain radiating down leg in dermatomal pattern)
3. If red flags are present

Appropriate Imaging When Indicated

• MRI without contrast is the first-line imaging study if radicular symptoms develop (91.7% sensitivity, 100% specificity for disc herniation) 2
• Plain radiography has limited utility for soft tissue causes and cannot visualize neural compression 2
• CT scan may be considered when MRI is contraindicated (83.3% sensitivity, 71.4% specificity) 2

Clinical Evaluation to Guide Management

Key Physical Examination Elements

• Straight-leg raise test (91% sensitivity but only 26% specificity for herniated disc) 1
• Crossed straight-leg raise (29% sensitivity but 88% specificity) 1
• Neurological examination focusing on:
  • L4 nerve root: knee strength and reflexes
  • L5 nerve root: great toe and foot dorsiflexion strength
  • S1 nerve root: foot plantarflexion and ankle reflexes
  • Sensory distribution of symptoms

Psychosocial Assessment

• Assess for factors that predict poorer outcomes:
  • Depression
  • Passive coping strategies
  • Job dissatisfaction
  • Higher disability levels
  • Disputed compensation claims 1

Management Approach

Initial Treatment

• NSAIDs (e.g., ibuprofen) as first-line treatment for pain relief 2
• Acetaminophen can be used as alternative or in combination with NSAIDs 2
• Avoid systemic corticosteroids (not recommended for low back pain with or without sciatica) 2

Activity Recommendations

• Begin with light intensity activities such as walking
• Gradually increase frequency and intensity following this progression:
  1. Weeks 1-2: Light activities for 5-10 minutes, 2-3 times per week
  2. Weeks 3-4: Increase to 15-20 minutes of moderate activity, 3-4 times per week
  3. Weeks 5-6: Progress toward 150 minutes per week of moderate intensity activity 2

Follow-up Recommendations

• Reevaluate if symptoms persist beyond 4 weeks 1
• Consider earlier reevaluation if:
  • Severe pain or functional deficits develop
  • Signs of radiculopathy develop
  • Older patient (as in this case) 1

Important Considerations

Common Pitfalls to Avoid

• Ordering unnecessary imaging for acute back pain without red flags
• Failing to recognize development of neurological symptoms requiring further evaluation
• Overlooking psychosocial factors that may impede recovery
• Prescribing opioids as first-line treatment

Special Considerations for This Patient

• Occupational factors (paramedic work involves lifting) may affect recovery and return to work
• Age >50 is a modest risk factor that should be considered in follow-up planning
• The decreased hip ROM may indicate referred pain from the lumbar spine or a separate hip pathology that warrants evaluation if it persists

Remember that most acute low back pain resolves within 4-12 weeks with appropriate conservative management 2, and imaging findings often correlate poorly with symptoms 3.