Download Low back pain

Chronic Pain:
New
understanding
paradigm
approach
Professor Milton Cohen
St Vincent’s Campus, Sydney, and Faculty of Pain Medicine, ANZCA
9 May 2016
To be covered:
 Comprehensive assessment of patients with CNCP
 Managing the social and psychological dimensions
 Pharmacological management
 Opioid prescription: when and how
 Other biomedical interventions
 Philosophies and types of PMPs
 Facilitating self management
“Johnny, are you in pain?”
“No, Mummy. The pain is in me.”
The Advertiser, 1927
Quoted in The Lancet , 30 June 2012
“Your pain is the breaking of the shell
that encloses your understanding.”
Kahlil Gibran
“To have pain is to have certainty;
to hear about pain is to have doubt.”
Elaine Scarry, 1985
Courtesy of Prof Deborah Schofield
Themes
 Complex biology of pain
 Sociopsychobiomedicala
ssessment and
management
Not a “broken part”
but a changed person
“The body”
is not the only thing
 Therapy of pain,
including opioids
Self-management
is the aim
PAI N
An unpleasant
sensory and emotional experience
associated with
actual or potential tissue damage
or described in terms of such damage
PAI N
An unpleasant
sensory and emotional experience
associated with
actual or potential tissue damage
or described in terms of such damage
A dominant paradigm…
Biomedical focus
Anatomical determinism
Dualism
…shift
Biopsychosocial
Sociopsychobiomedical
Neural plasticity
Interactionism
Biomedical Model
PAIN
(nervous system)
DISEASE
Problems with Biomedical Model of Pain
 Implies hard-wired certainty
 Absence of nociception defaults to
“psychogenesis”
 Excludes narrative of the sufferer
CNCP is a complex phenotype
[Campbell et al, Pain 2015;156:231-242; NDARC, UNSW Australia]
N=1514, CNCP taking prescribed opioids for >6 weeks
 Low rates of employment/ income
 Multiple “pain conditions”, poor physical health
 ~30% abuse/neglect
 ~ 50% depression; ~25% anxiety; >40% suicidal ideation
 >30% concurrent BZD; >50% concurrent antidepressant
 1:8 cannabis use disorder; 1:3 alcohol use disorder
Anterior cingulate cortical (ACC) activation
 Thermal injury
 Rectal distention
 Hearing pain words
 Viewing facial
expressions of pain
 Social exclusion
A model regarding brain circuitry involved in the transition
from acute to chronic pain. Apkarian et al. Pain 2011:152:S49-S64
Socio
psycho
social
psycho
Bio
biomedical
ENVIRONMENT
PERSON
BRAIN
AND
NERVOUS
SYSTEM
BODY
ENVIRONMENT
PERSON
BRAIN
AND
NERVOUS
SYSTEM
BODY
What’s happening
in your world
(“socio-)
What’s happening
to you as a person
(-”psycho-”)
What’s happening
to your body
(-biomedical”)
DISTRESS
BELIEFS
CULTURE
DISABILITY
MEMORY
EDUCATION
NOCICEPTION
BLACK FLAGS
BLUE FLAGS
ORANGE FLAGS
YELLOW FLAGS
RED FLAGS
Early detection of problems?
•Symptoms persisting past “healing”
•New pathology
•Iatrogenic factors
ORANGE FLAGS
•Unhelpful beliefs about injury
•Poor coping strategies
•Passive role in recovery
BLUE FLAGS
•Threats to financial security
•Sense of injustice
•Litigation
RED FLAGS
•Mental health disorders
•Personality disorders
YELLOW FLAGS
•Low social support
•Unpleasant work
•Low job satisfaction
•Excessive work demands
•Problems outside of work
BLACK FLAGS
RED FLAGS
•Symptoms persisting past “healing”
•New pathology
•Iatrogenic factors
Tenderness - Allodynia
 Pain in response to a non-noxious
mechanical stimulus
pressure, movement)
 Increased responsiveness
threshold) of nociceptors
(touch,
(lower
UNDERSTANDING “TENDERNESS”
Complaint of pain
Hyperalgesia/allodynia
Hyperalgesia/allodynia
in area of disease, damage
or inflammation (1°)
in clinically normal tissue (2°)
Peripheral sensitisation
Central sensitisation
CENTRAL SENSITISATION OF
NOCICEPTION
“Switch-on” of nociceptive pathways
in the central nervous system (spinal cord and brain)
 “Pain…might not necessarily reflect the presence of
a peripheral noxious stimulus.”
 “Pain could…become the equivalent of an illusory
perception…”
Woolf C. Pain 2011;152:S2-S15
NOCICEPTIVE
BARRAGE
UNDAMPENED
STRESS RESPONSE
NERVE
DAMAGE
SENSITISATION OF
CENTRAL NOCICEPTIVE PATHWAYS
SPONTANEOUS PAIN
ALLODYNIA
SPREAD OF PAIN
CLINICAL FEATURES SUGGESTING
CENTRAL SENSITISATION
 Absence of obvious tissue damage or disease
 Sensitivity to touch, movement
 Worsening pain after repetitive use (hyperpathia)
DIAGNOSTIC IMPLICATIONS
OF CENTRAL SENSITISATION
“Top-down” AND “bottom-up”
Avoid chasing nociception in region of pain
No language (yet)
A FALSE DICHOTOMY
“NOCICEPTIVE”
“NEUROPATHIC”
REPLACING THE DICHOTOMY
See Kosek E et al. Do we need a third mechanistic descriptor
for chronic pain states? Pain 2016, in press
“NOCICEPTIVE”
“NOCIPLASTI
C”
“NEUROPATHIC”
THERAPEUTIC IMPLICATIONS
OF CENTRAL SENSITISATION
Avoid chasing nociception in region of pain
Nervous system re-education
Pharmacological modification
of symptoms and excitability
A dominant paradigm shift
Biomedical focus
Anatomical determinism
Dualism
Sociopsychobiomedical
Neural plasticity
Interactionism
Our point of view as
observers
does not allow us to know
what it is like to be
the system being observed
Adolphs & Damasio 1995
Risks – to the patient - of having chronic pain
 Challenge observers’ view of the world
 Reinforce clinicians’ uncertainty
 Fail to validate health professionals’ effectiveness
Marginalisation
Discrimination
Stigmatisation
Risks – to the clinician – of chronic pain
 View of the world challenged
 Uncertainty reinforced
 Effectiveness not validated
“Negempathy”
Conscious avoidance of compassion
Negative projection
CLINICAL ENCOUNTER
SOCIAL DETERMINANTS
L
A
N
G
U
A
G
E
CLINICAL ENCOUNTER
ILLNESS
BEHAVIOUR
EMPATHY
HONESTY
PSYCHOLOGICAL
DISTRESS
ATTITUDES
& BELIEFS
EXPERIENCE
TOLERANCE
PREJUDICE
HOSTILITY
SUSPICION
CLINICAL
BEHAVIOUR
AFFECT
ATTITUDES
& BELIEFS
KNOWLEDGE
REFRAMING THE ENCOUNTER
Shared expertise
Neurobiology
Empathy
Language
To be covered:
 Comprehensive assessment of patients with CNCP
 Managing the social and psychological dimensions
 Pharmacological management
 Opioid prescription: when and how
 Other biomedical interventions
 Philosophies and types of PMPs
 Facilitating self management
The clinician’s trilemma
 Our patients believe that they can be “fixed”
 Not all our patients get better
 Our treatments have unpredictable effects
PRINCIPLES OF
THERAPY
AIMS
 Decrease pain as much as possible
 Increase function as much as possible
 Minimise adverse effects of treatment
MODALITIES
 Psychological
 Physical
 Pharmacological
 Procedural
PSYCHOTHERAPY
PHYSICAL
THERAPY
PHARMACOTHERAPY
PROCEDURES
“Treatment” of person with chronic pain
What’s happening
in your world
Relationships
Security
Work
What’s happening
to you as a person
Reframing
New learning
?Medications
What’s happening
to your body
Exploring the body
Movement
?Medications
?Procedures
CLINICAL IMPROVEMENT
Natural history
Spontaneous symptom fluctuation
Regression to the mean
Sampling bias
Hawthorne effect
Specific effects of therapy
“Non-specific” effects of therapy
PLACEBO (CONTEXTUAL) EFFECT(S)
Change(s) in illness
attributable not to a specific pharmacological or
physiological effect of a treatment
but rather to the sociocultural context
in which the treatment occurs
PLACEBOS AND CONTEXTUAL EFFECT
Contextual effect does not require a placebo
Non-placebo
characteristic effect + contextual effect
Powerful non-placebo
Weak non-placebo or placebo
effect
increased contextual effect
decreased contextual
Pharmacotherapy of
Chronic Pain
Ketocyclazocine Baclofen
k
GABAB
Opioids
m
Ketanserin
NK -1
d
Clonidine
2 - Methyl - serotonin
5 - HT3
a2
Primary Afferent Fibre
5 - HT2
Glu
Glu
SP
SP
Ketamine
Tricyclics
AMPA
GABAA
NMDA
Ca++
Damgo
Opioids
Morphine
Na+
GABAA
Cl-
K+
d
Cl-
K+
Adn
Midazolam
Midazolam
m
a2
m
Clonidine
d
K+
Adn
NK - 1
K+
5HT1B
GABAB
Baclofen
R - Pia Neca
Post Synaptic Element
Unconditional, Fast and
Strong. Locally adapting.
PRIME
Contingent, Medium speed
and Medium strength. Wind - up.
Adaptable, Slow Weak. Subject
to inhibition by K channel activation.
PRIME
PHARMACOTHERAPY

Non-opioid analgesics
paracetamol, NSAIDs

Weak µ-opioid agonists
codeine, tramadol, tapentadol

Strong µ-opioid agonists
morphine, oxycodone,
methadone, hydromorphone,
fentanyl

Mixed opioid ant/agonist

Adjuvant analgesics
buprenorphine
antidepressants,
anticonvulsants
Finnerup et al. The evidence for pharmacological treatment of neuropathic pain. Pain 2010, 150:573-581
The “Opioid Epidemic”
Australia 1990-2010
Population
29%
Pharmaceutical opioid base supply
228%
Per capita morphine equivalent
350mg
50
Ethics of Opioid Analgesia
for Chronic Non-Cancer Pain
OPIOPHILIA
 Patients’ right to pain
OPIOPHOBIA
 Patients’ motivations
relief
 Unpredictability of
 Sanctions on clinicians
opioid-responsiveness
 Adverse effects, including
addiction, not a problem
 More realistic view of
addiction
See also: Rich BA. Pain Clinical Updates 2007, vol XV, issue 9
Ballantyne JC, Fleisher LA. Pain 2010;148:365
Evidence for Efficacy of Opioids
in Chronic Non-Cancer Pain
 Diversity of subjects
 Complexities of non-somatic influences
 Variability with respect to substance abuse
 Primary outcomes
 Generally poor quality
Ballantyne JC, Shin NS. Efficacy of Opioids for Chronic Pain: A Review of the Evidence. Clin J Pain 2008; 24:469478
Evidence for Efficacy of Opioids
in Chronic Non-Cancer Pain
 Extrapolation to real-life situations
 Risks and benefits vary over time
 Opioid-responsiveness always a trial
Ballantyne JC, Shin NS. Efficacy of Opioids for Chronic Pain: A Review of the Evidence. Clin J Pain 2008; 24:469478
Principles of Opioid Therapy
for Chronic Non-Cancer Pain
1.
2.
3.
4.
5.
Comprehensive assessment
Failure of adequate trial of other therapies
Contractual approach to opioid usage
Practical considerations
Response to apparent increase in dosage requirements
RACP. Prescription Opioid Policy. 2009. www.racp.edu.au/page/health-policy-and-advocacy
Cohen ML, Wodak AD. Medicine Today 2010; 11:10-18 & 2012; 13:24-32
Faculty of Pain Medicine, ANZCA. Professional Document PM1, 2015.
anzca.edu.au/fpm/resources/professional-documents
Response To Difficulty Achieving Goals
in an Opioid Trial
 No change in pain despite improvement in function
 Opioid non-responsive
 Unsanctioned use
 Comprehensive reassessment
To be covered:
 Comprehensive assessment of patients with CNCP
 Managing the social and psychological dimensions
 Pharmacological management
 Opioid prescription: when and how
 Other biomedical interventions
 Philosophies and types of PMPs
 Facilitating self management
“More studies are needed…”

Shoulder pain
“There is some evidence from methodologically weak trials to indicate that some
physiotherapy interventions are effective for some specific shoulder disorders.”
(Green et al. Cochrane Database of Systematic Reviews 2003, Issue 2. Art. No.:
CD004258)

Low back pain
“In this systematic review, we present information relating to the effectiveness and
safety of the following interventions: acupuncture, analgesics, antidepressants,
back schools, behavioural therapy, electromyographic biofeedback, exercise,
injections (epidural corticosteroid injections, facet joint injections, local injections),
intensive multidisciplinary treatment programmes, lumbar supports, massage,
muscle relaxants, non-steroidal anti-inflammatory drugs (NSAIDs), non-surgical
interventional therapies (intradiscal electrothermal therapy, radiofrequency
denervation), spinal manipulative therapy, surgery, traction, and transcutaneous
electrical nerve stimulation (TENS).”
(Chou R. Clinical Evidence [Clin Evid (Online)] 2010 Oct 08)
Regarding “interventions”
? Rationale
 Central problem
? Evidence
 No sham controls
? Ethics
 Charging for placebo
“In our opinion, withdrawal of public funding
for spinal steroid injections for low back pain
and/or radiculopathy should be considered
on the basis of our knowledge
of the placebo nature of the treatment,
the costs and, not least,
because of the likelihood of harm.”
Harris IA, Buchbinder R.
Time to reconsider steroid injections in the spine?
Med J Aust 2013;199:237
“More studies [may not be] the answer…”
 “…the positive studies are false positives…”
 “No matter how many studies showed negative results, they
would not persuade true believers to give up their beliefs.”

Hall, H. Commentary. Pain 2011;152:711-712.
To be covered:
 Comprehensive assessment of patients with CNCP
 Managing the social and psychological dimensions
 Pharmacological management
 Opioid prescription: when and how
 Other biomedical interventions
 Philosophies and types of PMPs
 Facilitating self management
What does a good pain
management program look like?
 Not for “pain” but a person experiencing pain (PEP)
 Reframes the problem
 By provider
 Of PEP
 Recognises the context
 Sociopsychobiomedical framework
 Interaction
 Respects the nervous system
 Allodynia
 Drug effects
Trouble-shooting
What’s happening
in your patient’s world?
Relationships
Work
Recreation
What’s happening
to your partient as a person?
Understanding
Mood
?Medications
What physical treatments
are you recommending?
Movement
?Medications
?Procedures
To be covered:
 Comprehensive assessment of patients with CNCP
 Managing the social and psychological dimensions
 Pharmacological management
 Opioid prescription: when and how
 Other biomedical interventions
 Philosophies and types of PMPs
 Facilitating self management
Themes
 Complex biology of pain
 Sociopsychobiomedicala
ssessment and
management
 “Treatment” of
person with) pain
Not a “broken part”
but a changed person
“The body”
is not the only thing
(the
Self-management
is the aim
Acute pain
Chronic pain
Altered nervous system
Active tissue damage
Changed person
ALTERED ATTENTION
“HYPERVIGILANCE”
TRAUMA
ALTERED NOCICEPTION
“HYPERALGESIA”
CONTEXT
Relationships
Security
Work
PERSON
CNS
BODY
Reframing
New learning
?Medications
Exploring the body
Movement
?Medications
?Procedures
FACTORS INFLUENCING PLACEBO RESPONSES
Patient expectation
Conditioning
Physician expertise
Treatment impressive and
expensive
Placebo response (= response to placebo)
in the experimental setting
is a model for
contextual effect in the clinical setting
Case 1: F45
 Ankle injury 2y ago: “sprained”
 “CRPS” diagnosed 4m later
 4w inpatient PMP:
physio/hydro/benzo/pregabalin/nortriptyline/opioid/int
rathecal
 Suicidal ideation 6m later
 5+w admission for (long-standing) depression:
drugs/psychotherapy/TMS/ECT
 Personality and interpersonal issues identified…
Case 1: analysis
Biopsychosocial
•Biomedical diagnosis (?)
•One-size-fits-all approach
•Medicalisation:
•psychological issues
•drugs/procedures
•Trivial biomedical component
•Why no return to work?
•Delayed recognition of context
Sociopsychobiomedical
Case 2: F55
 Fell off chair 3y ago: “lumbar sprain”
 Massage/“physiotherapy”/heat/TENS
 Palexia/Lyrica/Maxigesic
 “Denervation” -?repeat
 “Adjustment reaction with depression”
 Antidepressant drugs/counselling
 “Pain management not helpful”
ALTERED ATTENTION
“HYPERVIGILANCE”
ALTERED NOCICEPTION
“HYPERALGESIA”
PAIN is one way, among many, that
threats to homeostasis are signalled
ALTERED ATTENTION
“HYPERVIGILANCE”
STRESSOR
THREAT TO
HOMEOSTASIS
CWP
ALTERED NOCICEPTION
“HYPERALGESIA”
Fear avoidance
A behavioural response to pain characterised
by a person excessively restricting
involvement in activities and exercises due to
heightened fear or anxiety about pain or reinjury (i.e. worry that any pain could cause
tissue damage).
Clinical Framework for the Delivery of Health Services
TAC & WorkSafe Victoria
Twin Goals
Rx
Injury
RTW
CLINICAL FRAMEWORK PRINCIPLES
1. Measure and demonstrate the effectiveness of treatment
2. Adopt a biopsychosocial approach
3. Empower the injured person to manage their injury
4. Implement goals focused on optimising function,
participation and return to work
5. Base treatment on the best available research evidence
CLINICAL FRAMEWORK PRINCIPLES
- from a clinical perspective 1.
Adopt a sociopsychobiomedical approach
2.
Implement goals focused on optimising function,
participation and return to work
3.
Empower the injured person to manage their injury
4.
Base treatment on the best available research
evidence
5.
Measure and demonstrate the effectiveness of
management
Terminology
 Inappropriate prescriber behaviour
 Unsanctioned opioid use
 Problematic use (patients)
 Illicit use (third parties)
Problems
Diagnosis
Tolerance
Hyperalgesia
Pseudoaddiction
(Hormonal changes)
(Immune modulation)
Unanswered Questions
 Is opioid therapy beneficial in the long term?
 Is there a differential effect on efficacy and safety?
 Is there a ceiling dose?
 How likely is unsanctioned use?