HNN Topic 13 - Chronic Pain/Illness, Low Back Pain Flashcards
List treatments of non-specific LBP
- TENS
- Physiotherapy
- Accupuncture
- Epidural injections - medial branch of dorsal primary ramus
Describe the difference between nociceptive and neuropathic pain and give examples
- Nociceptive is due to tissue damage, e.g. osteoarthritis, rheumatoid arthritis
- Neuropathic is due to nerve damage, e.g. post-herpetic neuralgia, painful diabetic neuropathy, post-stroke, lumbar radicular pain
List the factors which affect pain
- Biomedical
- Psychosocial
- Affective - cognition
- Ethnocultural
What factors can hinder management of low back pain?
- Progressive pathology
- Passive - belief that pain and activity are harmful, sickness behaviour (extended rest)
- Depression
- Problems - social, work, financial
List the afferent fibre types involved in chronic pain
- A beta
- A delta
- C fibres
A beta fibres usually not involved in pain, recruited in allodynia
How is pain assessed?
- History, examinations
- Characteristics - site, radiation, quality, severity, duration, frequency, exacerbating/relieving factors, associations
- Impact on physical and mental health/function and quality of life
- Verbal assessment of severity (0-10)
What does the ‘sick role’ include?
- Rights - exempt from some social roles, not blamed for illness
- Responsibilities - try to get better, seek help and cooperate with help given
- Chronic illness? Blame e.g. smokers and lung cancer?
Define chronic pain
- A sustained sensory abnormality/ongoing peripheral pathology (3+ months)
- Maladaptive - no protective function
- Induction is evoked or spontaneous
Define hyperalgesia
Heightened perception of pain - sensitisation of nociceptors
Can be caused by opoid use
List the sources of LBP
- IVD
- Bulge, rupture
- Vertebrae
- Osteoarthritis, lumbar instability
- Joints
- Facet, sacroiliac
- Muscle
- Paravertebral, gluteal
- Ligaments
- Anterior and posterior longitudinal
- Initially may be focal lesion, over time grows to be multifactoral problem
List the obstacles which can prevent successful adaptation to living with a chronic illness
- Intrapersonal, personality (dependent/paranoid/narcissistic/histrionic
- Psychiatric illness, substance misuse
- Characteristics of illness - pain, sleep disturbance
- Characteristics of treatment - unpleasant, inconvenient
- Finances, social support, culture, religion
What is important to consider when treating LBP?
Target treatment to patient depending on risk of chronicity
Describe use of opiods
RA/OA > neuropathic pain > LBP > visceral > fibromyalgia
Screen for risk of dependency, monitor for misuse/addiction
What are the symptoms of non-specific LBP
- Tension
- Pain
- Stiffness
Define illness behaviour
Mechanic (1978)
- Way in which symptoms and illness are perceived, evaluated and acted upon
- Experience of symptoms and their meaning/consequences and the reaction to them
List the characteristics associated with coping badly with chronic illness
- Reluctant to compromise/change
- Passive approach, denial
Describe the neuropathic components of LBP
- Pain due to compression of dorsal root ganglion
- Abnormal impulses can over-stimulate ascending pathways to the brainstem, thalamus and limbic system
- Pain awareness develops
List the types of sensitisation to pain
- Primary - peripheral sensitisation, occurs directly in damaged tissues
- Secondary - centra sensitisation, occurs in surrounding undamaged tissues
Define allodynia
Pain elicited by stimuli which normally only evoke innocuous sensation
List adjuvants used with neuropathic analgesia
- Anti-depressants e.g. amitryptyline
- Anti-convulsants e.g. gabapentin, pregabalin
- Anti-arrhythmics e.g. lidocaine
- Others - ketamine, capsaicin, clonidine
How does central sensitisation occur?
- Changes in CNS - modification of neurons, amplification of the excitability of neurons within the CNS
- Interneurons - decreased GABA and glycine (inhibitory)
- CPM - decreased noradrenaline and serotonin (modulate pain)
List the symptoms which can be caused by nerve damage
- Positive symptoms - spontaneous pain and tingling, radiating to lower legs
- Negative symptoms - weakness or loss of sensation, radiating to lower legs
Describe the types of pain
- Acute (e.g. trauma, post-operative) vs. chronic (LBP)
- Cancer vs non-cancer
- Nociceptive vs neuropathic
List the aspects of treatment of LBP
- Prevention - back care, exercise, good acute pain control
- Pathology - treat
- Physical therapies - maintain activity, physio, TENS
- Pharmacotherapies
- Procedural - regional analgesia, injections
- Psychologically based - eduction, relaxaton, distraction
What are the risk factors for not returning to work following LBP
- Poor job satisfaction
- Smoker
- Work injury
- Unemployed
How are cytokines involved in chronic illness?
- Mediate many non-specific symptoms - weakness, fatigue, poor concentration, anhedonia
- Cognitive and behavioural interventions should target this - exercise, activity scheduling
Describe the ladder of analgesia used to treat LBP
- Paracetamol/NSAIDs (NSAIDs have more side effects)
- Codeine, dihydrocodeine (CP450 CYP 2D6 - genetic deficiency), dextropropoxyphene (OD risk)
- Tramadol
- Morphine, oxycodone, fentanyl, bupenorphine, methadone, hydromorphone, diamorphine, pethedine
Which causes should be ruled out before diagnosis of non-specific LBP?
- Malignancy
- Infection
- Fracture
- Inflammatory - ankylosing spondylitis
How does introspection effect perception of health?
Introspective individuals experience more physical/psychological distress, use health services more and are more likely to define common bodily sensations as symptoms
How does the idea of locus of control contribute to health and illness?
- Internal locus of control = decisions made for yourself
- Take responsibility for actions and health
- More likely to adapt successfully to chronic illness
- External locus of control = decisions made by outside force
- Passive, don’t take responsibility
- Negative implications for disease
- Spectrum - people are usually somewhere between the two extremes
How is nociceptive pain classified?
Somatic (skin, muscle, bone) or visceral (internal organs)
What are the common problems associated with chronic pain?
Problems with sleep and anxiety/depression - all are interlinked
List the characteristics associated with coping well with chronic illness
- Flexible, open to suggestions/change
- Optimistic
- Interal locus of control
- Appropriate emotional expression - feelings of anxiety/depression common, not necessarily pathological
- Self management
- Finding benefit
How does peripheral sensisation occur?
- Release of mediators creates ‘inflammatory soup’ which changes nociceptors to low threshold
- Mediators which activate nociceptors
- Potassium, serotonin, bradykinin, histamine
- Mediators which sensitise nociceptors
- Prostaglandins, leukotrienes, substance P, cGRP, noradrenaline
Describe the nociceptive components of LBP
- At site of problem
- Caused by release of inflammatory mediators from damaged tissue
- Activates peripheral nociceptors, which activate afferent sensory fibres to the dorsal horn and up to the brain
List the ‘red flags’ which indicate a serious cause of LBP
- Weight loss
- PMH of malignancy
- Fever
- Signs of systemic inflammatory disease
- Anatomical change
- History of trauma
- Loss of bowel/bladder control - cauda quina syndrome
- Neurological signs (radiculopathy)
Describe the radicular pain of LBP
- Travels to lower limbs in narrow band
- Below knees - neuropathic pain
- Burning, stabbing, dysaesthesias
- Associated with sensory/motor deficits
- Provocation by straight leg raise
List the characteristics of neuropathic pain
Shooting, electric shock-like, burning, tingling, numbness
Compare somatic to visceral nociceptive pain
- Somatic
- Well localised
- Dermotomal radiation
- Sharp, aching, gnawing
- Constant/periodic
- Associations rare
- Visceral
- Vague distribution
- Diffuse radiation, to body surface
- Dull, cramp, dragging pain
- Often periodic
- Associations - nausea, sweaty, increased HR/BP
What kind of pain is LBP?
- Nociceptive
- Neuropathic
