Low%20back%20pain Diagnosis
Diagnosis
Red Flags
- Take note of symptoms that may be secondary to underlying diseases
- Incapacitating pain
- Unrelenting night pain
- Cancer
- Infection (tuberculosis, pyogenic abscess)
- Fracture
- Cauda equina syndrome
- Bowel/bladder dysfunction
- Saddle anesthesia
- Bilateral radiculopathy
- Progressive motor weakness
- Spondyloarthropathies
- Pain at night
- Insidious onset
- Improvement with movement
Yellow Flags
- Psychosocial factors that may contribute to the chronicity of the disease
- Mood changes
- Level of job satisfaction
- Attitude toward treatment participation
- Attitude towards the disease
- Involvement of loved ones with the management
Classification
Non-specific Low Back Pain
- Low back pain without identifiable specific causes
- Makes up 85-90% of all low back pain cases
- Also includes pain felt in the proximal lower extremities
Specific Spinal Pathology
- Patients with low back pain with associated mobility deficits caused by severe or progressive neurologic disorders or comorbidities
- Specific spinal pathology includes cauda equina syndrome, tumor, infection, ankylosing spondylitis, inflammatory disorders
Low Back Pain Associated with Radiculopathy or Spinal Stenosis
- Dermatomal pain with or without neurologic deficits
- Most often caused by nerve root compression
Evaluation
Pain Intensity Level
Visual Analog Scale
- A subjective examination that quantifies how patients rate the level of pain
Oswestry Disability Index (ODI)
- A subjective tool used to evaluate a patient’s perceived functional disability
Score | Perceived Disability Level |
0-20% | Minimal disability |
21-40% | Moderate disability |
41-60% | Severe disability |
61-80% | Crippled |
81-100% | Bedridden |
Roland-Morris Disability Questionnaire (RMDQ)
- A disability measure to assess the subject’s disability caused by back pain
- Patients with minimal disability perceive their pain as a disease that can be managed even without treatment
- Patients with scores of 21-40% experience pain with regular movements (sitting, standing) and may complain of difficulty going to work
- May demand conservative treatments
- Patients with severely disabling pain are apprehensive to go about with their daily life if rigorous examinations and treatments are not provided
- Patients with ODI scores of 61-80% are those whose everyday activities are greatly affected
- Treatments and positive interventions are highly suggested
History
Pertinent Features
- Location of pain
- Duration of pain
- Frequency of symptoms
- Medical history (previous history of pain, treatment and treatment response)
- Presence of weakness or neurologic deficits
- Presence of red flags
Duration of Symptoms
Acute
- Onset of symptoms <4 weeks
Subacute
- Symptoms appeared 4-12 weeks prior to consult
Chronic
- Onset of symptoms >12 weeks before consultation
- Continuous or recurrent pain
- Experience pain for at least half the days in the past 6 months
Physical Examination
Neurologic Exam
- Examine muscle strength, deep tendon reflexes and sensation
- Presence of muscle atrophy
Laboratory Tests
- Complete blood count (CBC), erythrocyte sedimentation rate (ESR)
- Used to rule out presence of tumor or infection
Imaging
- Not recommended for patients with non-specific low back pain
- Should be considered if red flags are suspected, surgery is being contemplated, and presentation is unconventional
Magnetic Resonance Imaging (MRI)
- Imaging modality of choice
- Should be considered for assessment of radicular symptoms, asymptomatic low back pain, chronic low back pain with red flags, subacute or chronic radicular pain with no improvement seen after 6 weeks of treatment
- Indications:
- Neurologic deficit (foot drop, hip flexion, knee extension)
- Cauda equina syndrome
- Persistent and progressive severe pain even with conservative treatments
- Neoplasm is highly suspected
- Spondyloarthropathy is suspected
- Presence of infection highly likely
- Trauma
- Unresponsiveness to therapy and surgery is being considered
Computed Tomography (CT)
- May be considered in patients with acute or subacute radicular pain unresponsive after 4-6 weeks of therapy, presence of red flags
- CT myelography may be considered in patients with contraindications to MRI, if MRI is inconclusive, if with suspected bone neoplasms or with severe incapacitating back/leg pain
Radiography
- Recommended for the evaluation of obvious deformities, acute low back pain with presence of red flags, and vertebral compression fracture
- Anteroposterior (AP) and lateral views are indicated for acute low back pain that persists for >2 weeks without red flags
- Flexion extension and oblique views are indicated when lumbosacral spine instability, spondylolysis or spondylolisthesis is suspected
- Myelography may be considered if presentation of disease is uncommon
Radionuclide Scanning
- May be used in patients suspected to have vertebral cancer
Nerve Conduction Studies
- Successfully identify precise cause of nonradicular pain
- May be considered for patients at high risk for extra-spinal pathologies
Electromyography (EMG)
- May be considered for assessing acute low back symptoms and chronic non-specific low back pain
- Needle EMG may be considered in patients with probable nerve root dysfunction of the lower extremities whose symptoms persist for >4 weeks
Spinal Diagnostic Interventional Techniques
- Eg facet joint nerve block, sacroiliac joint injection, provocation discography
- Consistent pain relief every time the affected nerve is anesthetized repeatedly may accurately identify the cause of low back pain
Invasive Diagnostic Procedure
Lumbar Provocation Discography
- Identifies intervertebral disc pathologies causing low back pain
- Indicated for patients with chronic low back pain with symptoms inconsistent with findings of MRI/CT scan
- Studies show that lumbar discography is more accurate than myelography