2History 1872 Mitchell described a syndrome of causalgia: Limbs of American Civil War soldiers who sustained nerve injuriesBurning pain, hyperaesthesia, trophic changes with glossy skinThe nomenclature relates to the Greek ‘kausis’ burning and ‘algos’ pain after a nerve injury1901 Sudeck (bone changes after injury)1940 Reflex Sympathetic Dystrophy (RSD)1864 Mitchell described causalgia after treating casualties from American civil war. Pain often accompanied by including various sensory disturbances;temperature and sweating changes; glossy and other disturbances of the skin, subcutaneous tissues, muscles and joints; paralysis; and involuntary movements.1940 Evans described the term RSD. Evans envisaged that prolonged bombardment of pain impulses set up a "vicious circle of reflexes" in the spinal cord that generated efferent activity in the sympathetic system leading to spasm in the peripheral blood vessels. As a consequence there was leakage of fluid from the capillaries which eventually caused dystrophic changes in peripheral tissues.The French surgeon Leriche had already noted that the limbs of patients with causalgia showed features that he thought reminiscent of vascular insufficiency. Because patients with ischaemic limbs were often treated by sympathectomy, Leriche argued by analogy that causalgia was due to an "irritation of the sympathetic" and might be alleviated by sympathectomy. These notions were later extended to RSD, although few noted that Leriche was later to retract his hypothesis.
3CRPS: NomenclatureThe nomenclature of CRPS Types I, II was adopted after a Consensus Conference in 1993Standardised terminologyAvoid unsustainable pathophysiological implicationsTake up has been patchy but increasing: 11% of articles between 1995 and 1999 used it but 3.5% 1995 & 27.5% in 1999Type II refers to major nerve injury, Type I to the rest.
4CRPS: Diagnostic Criteria A. Presence of an initiating noxious event or cause of immobilisation.B. Continuing pain, allodynia or hyperalgesia with which the pain is disproportionate to any inciting event.C. Evidence at some time of oedema, changes in skin blood flow, or abnormal sudomotor activity in the region of pain.D. This diagnosis is precluded by the existence of conditions that would otherwise account for the degree of pain or dysfunction.
5CRPS: Diagnostic Criteria One group found that the criteria did not discriminate between CRPS I and Diabetic Peripheral neuropathy and positive predictive value between 40 and 60%.Criteria used in a check list can improve PPV to 0.91, sensitivity to 0.71 and specificity to 0.95Baron suggests current presence of 3 symptoms and 2 signs.
6Pathophysiology:It can be shown that cooling the body with affected limb isothermic causes pain associated with sympathetic tone.Controversial pharmacological challenge of Raja etcSome studies have demonstrated an overall decrease in sympathetic nervous system activity explaining theAcute ‘hot’, hypercirculation phaseChronic ‘denervation supersensitivity’ phase with the cold blue limb.
7Pathophysiology:Most of the following have been demonstrated in animal models of nerve damage.Peripheral changesExpression of adrenoceptors on a subset of C-fibres, ORNoradrenaline mediated release of prostanoidsCentral changes‘wind up’Autonomic/somatic crosstalk & sprouting after nerve injury.
8Pathophysiology:Sympathetic nervous system elaboration of noradrenalin can activate mast cells, inviting a immuno-inflammatory aspect to this.
9Na+ Ca++ Ca++ Mao et al, Pain, 1995 AMPA-R NMDA-R mGluR G Mg++ IP3 SPGluAMPA-RNMDA-RmGluRGMg++Na+IP3Ca++Ca++L-argPKCactivationGeneexpressionNosNO
10Practical Clinical Features: PainAllodyniaTemperature changeColour changeSweatingDystrophyMotor changeNon dermatomalShould be markedUncommonNon-specific
11Practical Clinical Features: A continuum from:Icy cold, immobile, dripping with sweat, profound allodyniaTOHey! The X-ray looks OK … so how come it still hurts?
12Practical Clinical Features: There exist a number of potential differential diagnoses, the most common and important one is DISUSE secondary to persistent pain, (where the clinical signs are likely to be less marked).Unrecognized local pathology(sprain, #, sepsis, cellulitis, allergy)Vascular insufficiency (Raynaud’s disease, thromboangiitis obliterans, thrombosis)
13Practical Clinical Features: In all cases, the aims of treatment must be considered through the same process as any other patient with chronic pain.RESTORATION OF FUNCTION !
14Treatment algorithms Guideline published in 1998 Functional restorationPhysical and psychological methodsTo move through to another modality if no response in defined periodConsensus report Complex Regional Pain Syndrome:Guidelines for therapy Stanton Hicks et al Clin J of Pain 14: (now more recent)
18Timing of treatment97% believed better outcome if referred within 3 months of onset
19Evidence based guidelines Don’t really existCochrane data base of RCTsCritical analysis of 22 RCTsPoor methodologyOnly looking at one modalityDifficult to compareCalcitonin deceases pain of CRPSPerez et al Journ of Pain and Sympt Mgt 21, No6, June 2001
20What do we know? Oral corticosteroids are effective (2 papers, 1 RCT) Bisphosphanates:Alendronate improved bone density with a trend to decrease in pain and swellingClodronate improved pain substantiallySpinal cord stimulation – moderate improvementSome support for:DMSO creamEpidural clonidineIntravenous bretyllium, ketanserin
21What do we know? IVRB guanethidine is ineffective, bretyllium works (single trial)Ketanserin effectiveKetorolac effective (1 paper)
22A Reasonable Approach: Physiotherapy – (rest or mobilisation)Adequate analgesiaEarly pulse of corticosteroidsEarly referral to Pain Clinic for:Repeated temporary sympathectomiesEpidural clonidineBisphosphanatesLong term management of chronic pain
23Case study 1: History Mrs C Italian woman 70 years old History: 3mths ago gardeningStick pierced palm R handHot, swollen, dry, painfulTreated antibiotics, slingdeteriorated
24Case 1: History Referred to orthopaedic hand surgeon ? Hysterical, ?CRPS type 1unable to move arm, fingersunable to hold knife and forkunable to do washing, cooking
25Case 1: History Investigations Referred to pain clinic x-ray, bone scan, ultrasoundinflammatory markersReferred to pain clinic
26Case 1: Examination Pain on light touch, Increased reaction to pain in most of arm viz palm, classic tender pointsMotor neglect.All upper limb movements impairedtissue swellingtemperature cooler than other limbcolour change
27Case 1: Management Management: Initial TCA, oxycontin, physiotherapycease sling,start hanging washing on clothes lineSeries of 3 stellate ganglion blocksGood response for some days with lasting improvement(SMP)Combined with physiotherapy:EMLA cream to palm, trigger point injections extensor origin
28Case 1: Management Outcome good. Swelling gone, Movements substantially improvedFunction: returned to most activitiesResidual thickening of palmar flexion tendon middle fingerSwelling substantially reducedPain Medications ceased
29Case 2: History Mr U Turkish man aged 48 Injured at work end 1999 conveyor belt fault results in open injury to R handlaceration palmar branch of digital nerverepair of digital nerve
30Case 2: History Pain increased No progress with hand therapy burning, painful on light touchextending up armNo progress with hand therapyReferred to pain clinic for SGBs
31Case 2 : Examination Wearing glove Holding arm up close to chest difficulty swinging arm/initiating movementdecrease grip strengthHand cold blue sweaty, swollen
32Case 2 : Management Diagnosis of CRPS type 2 Trial of oral medications neuorpathic agents, SR opioids, TCAsTrial of stellate ganglion blocks/ activationtemporary improvement (SMP)poor complianceMulti-disciplinary pain assessment
33Case 2 : Management Not suitable for pain management seeking cure unresolved anger/ litigationReferred for in-patient rehabilitation program (Plan: Cx epidural/ phys ther)Unsuccessful
34Case 2 : Managementfurther interventional Mx by pain specialist number 3guanethidine blocksSpinal cord stimulationUnsuccessful
35Case 2 : Management Further deterioration now back and leg pain, using sticknot working/ low function at homedepressedarm wasted, sweaty hand, no movementheavily involved with litigation,still focussed on cure and blameseeking multiple medical opinions
36Case 2 : ManagementASSESSED AS “NOT READY” for CBT based Pain Management Program
37Case 3 : History Mr M.R. Aged 24, Australian born Had a venipuncture from R cubital fossa (lateral aspect) November 2000Felt pain shoot up to shoulder/ felt faint36hrs later woke up with clawed R handHas not been able to open hand sinceHas not worked since
38Case 3 : History Referred by GP for pain management 2 overdoses Had been working at previous job for 3 days prior to VenipuntureNo real indication for VPdid not attend a doctor prior to VPLitigation in progress against pathology firm
39Case 3 : HistoryNow living with grandparents who are “looking after him”Has initiated referral to multiple specialistsNo reports availableDifficulty contacting referring GPUsing self prescribed splints at night
40Case 3 : Examination Presentation agitated conflicting history with MotherPain not a major complaintBoth hands cool sweatyHolding R hand in tight clawResistance to opening
41Case 3 : Management No wasting in arm in general Increased forearm muscle bulkPossibly some wasting dorsum of handNo difference in temperature, swelling, sweatingNo allodyniaNo motor akinesia of arm in generalNormal movements of shoulder and upper arm. Cannot move fingers
42Case 3 : Management Diagnosis? Management ??????????Nerve injury ?????????CRPS??Conversion disorderManagementFull assessment (multi-disc)Counselling/ ReassuranceNo medications, general gym program
43Case 3 : Management Participating in competitive manner in Gym program Enjoys being videoedHas taken up a correspondence course (sports psychology)Will have an EUAUnable to get any reports
44Case 4 : HistoryMRS B58 year old woman (Australian born)Working as nurse in aged careMCA 1997: injured shoulder and ankle(soft tissue)Recovered, RTWPersistent swollen R legIntermittent shoulder stiffness
45Case 4 : History 1998 R leg gave way, fell fractured ankle POP/ int fixnpain and spasm swelling persistent problem when in POPprolonged rehabilitation 2X 3 mths IPpersisting pain, swelling, spasm2 further operationsNo progress, Referred to pain clinic
46Case 4 : Examination Pleasant co-operative woman Wearing rigid ankle brace/ using wheelchairleg swollen, cool compared to L sideintense allodynia, skin dry, discolouredmultiple tender points over entire leg, back shoulderout of brace grossly abnormal gait and devel of spasm on light touch/ movet
47Case 4 : Management Management initial Oxycontin/ gabapentin: Good analgesiaNo improvement in function/spasmLumbar sympathetic blockExcellent block with no change in symptoms (SIP)
48Case 4 : Management Case conference Rehab/ Physio in-patient admission: epidural opiate/ clonidine/ Local AnaestheticAllodynia/ spasm disappearedgait re-training, gym programceased all analgesicsreturned to normal activitiesno splint/ no wheelchairskin/ temp/ swelling abated
49Case 4 : Management 12 months later noted recurrence of spasm and pain skin changes/ allodyniatrial hydrotherapy/ gymfinding this difficult,further deteriorationrequested epidural treatmentunderwent multi-disc assessment
50Case 4 : Management Cure focussed, not interested in CBT Program Admitted for epiduralSimilar response to previousPt anxious that found walking difficult.Had persistent muscle crampReferral to IP rehab (Not accepted by TAC)OP physio attempted: poor progress
51Case 4 : Management became increasingly frustrated by TAC Frustrated that not curedTold that time to accept as chronic problemReacted to thisNow overall improvement, walking/ holidaying in USA
52Role of Primary Care Physician (1) DIAGNOSIS early(2) Early Use of adequate analgesia to promote normal activity/ postureactive physio/ not passive/ gentle reactivation.if physio cannot progress 1st step is increase in time based analgesia(3) Early referral to Multi disciplin PUurgent, not to go on long waiting list
53Be Aware Some pain specialists unimodal approach diagnostician eg phentolamine infusion/ guanethidine block/ no response/ dischargeinterventionist: blocks/ more blocks/ spinal cord stimulation/ no rehab/ psychrehab/ no intervention/ pain reliefpsych/ no intervention/ rehab
54Be Aware Adequate education/ counselling patients ill informed/ self help groups/ Internet: progressive diseaseexplanation of the importance of return to normal functionavoid surgery if possible/ only if appropriate and covered by analgesiaRole of cognitions/ depression/ litigation as mediating factors