Low back pain

Musculo-Ligamentous Injuries

• Low back pain due to soft tissue injury:
  • Local pain on palpation (mild to severe)
  • No paresthesia (exceptions)
  • No muscle weakness in legs or feet
  • Paraspinal muscle spasm (may be excruciating)
  • Relieved by rest, exacerbated by motion
  • May begin immediately or gradually after trauma (usually within 24 hours)
• Diagnosis based on mechanism of injury (MOI), location of pain, and exclusion of nervous system injury and other systemic diseases

Chiropractic Care

• HVLA (high-velocity, low-amplitude) may be contraindicated if severe/acute
• Limiting motion decreases muscle strength, flexibility, and circulation
• Gentle stretching and exercise preferred treatment to increase circulation and facilitate healing

IVD and Facet Degeneration

• May cause radiating pain if degeneration causes nerve root impingement
• IVD bulging/herniated into IVF (intervertebral foramen)
• Facet hypertrophy (severe expanding into IVF)
• Facet pain referral to:
  • Buttocks and posterior thighs

Nerve Root Irritation

• Direct compression (mechanical pressure)
  • Disc degeneration/Lumbar radiculopathy (usually unilateral)
  • Bony encroachment (arthritic hypertrophy, spondylolisthesis, spinal stenosis)
• Chemical changes:
  • Nucleus pulposus inflammatory to nerve roots
• Neuroischemia (spinal stenosis)
• Viral infection:
  • Causes inflammation of the nerves

Lumbar Radiculopathy

• Pathology of a lumbar nerve root
  • Herniated disc (degeneration, trauma, or both)
  • Facet arthritis/bone spurs
  • Spondylolisthesis
• Absolute contraindications to HVLA:
  • Spinal cord or meningeal tumors and cysts
  • Hematomas (cord or spinal canal)
  • Spinal malignancies
  • Aggressive benign tumors
• Need to determine level involved:
  • Patient history
  • EMG/NCV nerve testing
• Surgery may be necessary:
  • Unrelenting pain
  • Severe functional impairment
  • Incontinence (CES-SURGICAL EMERGENCY)

Radiating Pain and Dermatomal Patterns

• Sciatica (S1-S5):
  • Buttocks → posterior legs → lateral ankles
• L5:
  • Postero-lateral thighs wrapping around to the anterior foreleg
• L4:
  • Lateral-anterior thighs wrapping around to antero-medial foreleg

Myotomes and Muscle Strength Testing

• Myotome: group of muscles stimulated by a single spinal nerve
• Upper extremities:
  • C5: Deltoid and Biceps (C6 too)
  • C6: Wrist Extensors
  • C7: Triceps/Wrist Flexors/Finger Extensors
  • C8: Finger Flexors
  • T1: Finger Abduction/Finger Adduction
• Lower extremities:
  • L3: Hip Flexors
  • L4: Knee Extensors
  • L5: Knee Flexors
  • S1: Plantar Flexors

Spinal Stenosis

• Central Canal Stenosis: narrowing of the central spinal canal
• Foraminal Stenosis (lateral): narrowing of the lateral recesses of the spinal canal

Cancer Red Flags

• Patient history:
  • History of cancer
  • Unexplained weight loss
  • Pain lasting longer than one month
  • Pain not relieved by bed rest
• Specificity and sensitivity:
  • Highly sensitive test: more likely a – test is really – for a condition
  • Highly specific test: more likely + test is really + for condition
• Cancer summary:
  • Patient history is most useful in detecting underlying cancer
  • >50 yoa
  • History of cancer
  • Unexplained weight loss
  • Pain > one month
  • Pain not improved by conservative therapy
  • Pain not relieved by bed rest

Absolute Contraindications

• WHO Guidelines list of absolute contraindications for HVLA adjusting:
  • Some anomalies
  • Acute fracture
  • Acute infection
  • Spinal malignancies
  • Hematomas (cord or canal)
  • Frank disc herniation with accompanying signs of progressive neurological deficit

Spinal Infections

• Acute spinal infections are absolute contraindications to HVLA thrusts
• LBP caused by spinal infection – incidence 0.01%
• Usually bloodborne
• Presence of fever: high specificity (SPIN)

Compression Fractures

• Red Flags:
  • Osteoporosis
  • Corticosteroid usage
  • >70 yoa
  • >50 yoa
  • History of trauma
• Specificity = positive rules in
  • Patient > 70 yoa? Yes + LBP = 96% specific for compression fracture
  • Patient > 50 yoa? Yes + LBP = 61% specific for compression fracture
  • Long-term corticosteroid usage? - very high specificity (0.99)
  • Is there a history of trauma? Yes + LBP = 85% specific for compression fracture

Ankylosing Spondylitis

• 5 screening questions for AS:
  • Morning stiffness?
  • Discomfort improves with exercise?
  • Onset before 40 yoa?
  • Did symptoms begin slowly?
  • Has the pain persisted for a minimum of 3 months?
• If the pt answers ‘yes’ to at least 4/5 of the screening questions → + for AS
• Predictive value of a + screening test is typically low for very rare conditions
• Sensitivity and specificity vary from one study to another

Evidence of Neurologic Compromise

• Causes of neurologic compromise:
  • Herniated disc may compromise neurological structures
  • Cauda equina
  • Spinal cord
  • Nerve root

Low Back Pain: General Information

• The low back (lumbar area) provides structural support, movement, and protection of certain body tissues.
• Pain in the low back can result from conditions affecting the bony lumbar spine, intervertebral discs, ligaments, spinal cord/nerves, lumbar musculature, internal organs, and skin.

Origins of Low Back Pain

• Anatomic and physiologic causes:
  • Musculoligamentous injuries
  • Degenerative changes in intervertebral discs (IVD) and facets
  • IVD herniation with nerve root irritation
  • Spinal stenosis
  • Anatomic anomalies
  • Underlying systemic disease
  • Visceral disease
• Red flags for low back pain:
  • Unsteady when standing or walking
  • Difficulties passing/controlling bladder or bowels or numbness in either area
  • Previous history of cancer or osteoporosis
  • Back pain accompanied by unexplained weight loss or fever
  • Bleeding disorder

Musculo-Ligamentous Injuries

• Lumbar strain/sprain (acute/chronic):
  • One of the most common causes of low back pain
  • May present with compensatory hypolordosis
  • Can result from hypertrophic degenerative changes

Anatomic Anomalies

• Absolute or relative contraindications:
  • Dens hypoplasia, unstable os odontoideum, basilar invagination, Arnold Chiari, etc.
  • Most lumbopelvic anomalies cause relative contraindications or none
  • Scoliosis – asymptomatic or symptomatic (severe)
  • Spondylolisthesis - asymptomatic or symptomatic (severe)

Systemic Disease

• Causes of low back pain:
  • Cancer – primary or metastatic
  • Spinal infections
  • Ankylosing spondylitis

Visceral Diseases

• May refer pain to the low back from abdominal and pelvic organs:
  • Bowel/bladder
  • Uterus/ovaries and prostate
  • Kidneys
  • GI (gallbladder, aorta, etc.)
  • Lymph nodes/tissue

Prevalence of Diseases Causing Low Back Pain

• Compression fractures: 4%
• Spondylolisthesis: 3%
• Malignant neoplasm of the spine: 0.7%
• Ankylosing spondylitis: 0.3%
• Spinal infections: 0.01%
• Spinal stenosis: prevalence unknown (common in older adults)

Diagnosing Causes of Low Back Pain

• Evidence of systemic disease or visceral disease, anatomic anomalies:
  • Pt. history/exam
  • Constitutional symptoms
  • Evidence of neurologic compromise (lumbar disc herniation, stenosis, CES)
  • Assess motor, reflex, and sensory function
• Evidence of social/psychological stress that could amplify/prolong pain:
  • Decrease pain inhibition
  • Somatic amplification serves the patient's needs for economic survival and maintenance of self-esteem
  • Illness behavior

Cancer Red Flags: Sensitivity and Specificity

• How likely a patient is to have or not have a condition based on test accuracy:
  • Sensitivity: 31%
  • Specificity: 98%
• M/C source of spinal malignancy: breast, lung, and prostate
• Patient history is most useful in detecting underlying cancer (compared to physical examination)
  • >50 yoa
  • History of cancer
  • Unexplained weight loss
  • Pain > one month
  • Pain not improved by conservative therapy
  • Pain not relieved by bed rest

Cancer Summary

• Patient history is most useful in detecting underlying cancer (compared to physical examination)
• In a study of nearly 2000 patients with back pain, no cancer was identified in any patient younger than 50 years and without a history of cancer, unexplained weight loss, or failure of conservative therapy (combined sensitivity 100%)
• Sensitivity 100% = zero false negatives