Types of Low Back Pain

Classification of LBP

• LBP due to mechanical spine problems: lumbar radiculopathy, spinal stenosis, cauda equina syndrome
• LBP due to systemic disease affecting the spine: neoplasms, infection, osteoporotic compression fracture, inflammatory arthritis
• LBP due to visceral disease: pelvic, renal, GI structures

Ddx of Acute LBP with Radiculopathy

• Mechanical: spinal fracture, lumbar disc herniation, cauda equina syndrome, piriformis syndrome, Iliotibial band syndrome
• Degenerative: spinal stenosis, spondylosis, spondylolisthesis, facet arthropathy, pseudoclaudication
• Inflammatory: sacroiliitis, greater trochanter bursitis, ankylosing spondylitis
• Oncologic: spinal neoplasms (most commonly metastatic)
• Infectious: vertebral lesion (infection, e.g. S1

Epidemiology of LBP with Radiculopathy

• Prevalence: 3-5% of population
• Male > female (3:2), especially in those over 40 and 50 years old respectively
• L5 radiculopathy is the single most common lumbar radiculopathy
• Pain experience: tingling, electric, burning or sharp, paresthesia (63-72%), radiation of pain into lower limb (35%), numbness (27%), muscle weakness (up to 37%), absent ankle reflexes (40%), absent knee reflexes (18%)

Risk Factors for LBP with Radiculopathy

• Social history: repetitive lifting and twisting motions, chronic overloading of disc, driving occupations, heavy industry work, military, smoking, overweight, sedentary lifestyle
• Medical history: prior trauma (fall, MVA), multiple pregnancies, history of back pain, chronic cough

History Intake for LBP with Radiculopathy

• Site: location of back pain
• Onset: how and when back pain developed
• Quality: throbbing, aching, sharp, dull, burning, pressure, numbness, tingling, or shooting
• Radiation: dermatomal distribution
• Time course: change in back pain over time
• Severity: scale of 1-10
• Pain is typically worse with: increased intradiscal pressure, Valsalva, weight bearing, standing, walking, sitting for prolonged periods
• Pain is typically better with: extension of the lumbar spine, recumbent position (knees flexed)
• Associated signs and symptoms: motor or sensory disturbances, saddle anaesthesia (if cauda equina syndrome is possible)

Patterns of Disc Herniation

• Bulging disc: loss/damage of annular fibers, associated with trauma, repetitive stress or aging, prognosis: regression (13%), complete disappearance (11%)
• Herniated disc - protrusion (prolapse): focal distension of the disc, annulus fibrosis remains intact, prognosis: regression (41%), complete disappearance (0%)
• Herniated disc - extrusion: nucleus palposus breaks through the annulus fibrosis, remains in the disc, prognosis: regression (70%), complete disappearance (15%)
• Herniated disc - sequestration: nucleus palposus breaks through the annulus fibrosis, displaced from the site of extrusion

L5 Radiculopathy

• Findings: weak hallux extension (sensitivity: 12-62%, LR+: 1.7, LR-: 0.7), weak ankle dorsiflexion, sensory loss in L5 distribution (sensitivity: 20-52%, LR+: 3.1, LR-: 0.8), asymmetric medial hamstring reflex (sensitivity: 57%, LR+: 6.2, LR-: 0.5)

S1 Radiculopathy

• Distribution of pain: sacral or buttock pain into the posterior aspect of the patient's leg, into the foot, or the perineum
• Physical exam: motor weakness: plantar flexion, paresthesia/sensory changes: sole, lateral foot and ankle, fourth and fifth toes, absent reflexes: ankle reflex (S1)
• Findings: weak ankle plantar flexion (sensitivity: 26-45%, LR+: NS, LR-: 0.7), ipsilateral calf wasting (sensitivity: 43%, LR+: 2.4, LR-: 0.7), sensory loss in S1 distribution (sensitivity: 32-49%, LR+: 2.4, LR-: 0.7), asymmetric achilles reflex (sensitivity: 45-91%, LR+: 2.7, LR-: 0.5)

Serious Disorders Affecting the Lumbar Spine

• Spondylosis: age-related degeneration of the spinal column (involves degenerative disc disease and facet arthropathy)
• Spinal stenosis: narrowing of the spinal canal, neural foramen and lateral recess, leading to compression of the nerve roots and neurogenic claudication
• Spondylolysis: weakness or stress fracture through the pars interarticularis
• Spondylolisthesis: slippage of one vertebral body with respect to the adjacent vertebral body

Panic Disorder

• Diagnostic criteria: recurrent, unexpected panic attacks with 4 or more of the following symptoms:
  • Palpitations, pounding heart, or accelerated heart rate
  • Sweating
  • Trembling or shaking
  • Sensations of shortness of breath or smothering
  • Feelings of choking
  • Chest pain or discomfort
  • Nausea or abdominal distress
  • Feeling dizzy, unsteady, light-headed, or faint
  • Chills or heat sensations
  • Paresthesias (numbness or tingling sensations)
  • Derealization (feelings of unreality) or depersonalization (being detached from oneself)
  • Fear of losing control or "going crazy"
  • Fear of dying
• At least one of the attacks has been followed by 1 month (or more) of:
  • Persistent concern or worry about additional panic attacks or their consequences
  • Significant maladaptive change in behavior related to the attacks

Mental Status Examination (MSE)

• Appearance and behavior: may present as well-kempt or disheveled
• Motor activity: may have psychomotor agitation
• Speech: may be fast or pressured; if in a panic attack, may have difficulty speaking (stammering, vocal tremor)
• Affect and mood: may describe mood as anxious, afraid, tense, exhausted, frustrated, "on edge", or irritable; or depressed
• Thought process: may include ruminations
• Thought content: extreme fear, sense of impending doom (in an attack); anticipatory anxiety about having another attack (between attacks)
• Perception: often a negative view of themselves and of the world
• Sensorium and cognition: may have difficulty concentrating, mind blank, or confused during an attack
• Insight: often aware fears are out of proportion to the actual threat
• Judgement: tend to use avoidance behaviors

PHQ-PD Module

• Questions to assess panic disorder:
  • Have you had an anxiety attack with sudden fear or panic in the last 4 weeks?
  • Has this ever happened before?
  • Do some of these attacks come suddenly, out of the blue, in situations where you do not expect nervousness?
  • Do these attacks bother you a lot or are you worried about having another attack?
  • Have you had these symptoms during your last bad anxiety episode?

Autonomic Nervous System (ANS) Questionnaire

• Questions to assess panic disorder:
  • Have you ever had a spell or an attack when all of a sudden you felt frightened, anxious, or very uneasy?
  • Have you ever had a spell or attack when for no reason your heart suddenly began to race, you felt faint, or you couldn't catch your breath?

Panic Disorder Screening Questionnaires Scoring

• PHQ-PD (1- or 5-item) and ANS can be used to screen for panic disorder
• Severity often assessed using a different questionnaire (e.g. PDSS-SR)
• Likelihood ratios to identify panic disorder (PD) using PHQ-PD 1, PHQ-PD 5, and ANS questionnaires

Adjustment Disorder

• Definition: a maladaptive emotional and/or behavioral response to an identifiable psychosocial stressor
• Prevalence: 1-2% (general), 5-20% (outpatient mental health visit), 27% (recently unemployed), 18% (bereaved)
• Risk factors: significant life event(s)
• Diagnosis: by clinical interview (according to DSM-5 criteria), no validated assessment tools
• Timeline: onset shortly after stressor, typically resolves within 6 months after stressor has stopped (or becomes classified as 'chronic adjustment disorder')
• Character: with anxiety, depressed mood (may include suicide attempt), mixed, with misconduct, or unspecified
• Management: patient education, referral to psychotherapy, psychiatry
• Prognosis: 71% recover within 5 years, 76% comorbidity with substance abuse

Other Disorders

• Stress: a physical or mental response to an external stressor, considered a risk factor, an exacerbating factor, and a treatment target – not a diagnosis itself
• Depressed mood: a depressive syndrome that causes distress and psychosocial impairment for at least 2 weeks, but is not considered clinical depression (aka. major depression)
• Dysthymic disorder: depressed mood for most of the day, more days than not, for at least 2 years