Complex Regional Pain Syndrome (CRPS) is a unique type of primary pain syndrome with regional (normally hands, feet, arms or legs; sometimes other locations) distribution that is disproportionate in the intensity or duration of pain, after trauma or injury.
It is a multi-systemic disorder with severe pain; affecting musculoskeletal systems, the peripheral and central nervous systems. The main treatment modalities in clinical practice are pharmacologic approaches, cognitive behavioural therapy and physical rehabilitation.
Recently, with patients suffering devastating effects of chronic pain with progression to amputation in some cases, great strides in understanding disease mechanisms have enabled us to address the problem aggressively early with minimally invasive therapies that lead to improvement in most cases sooner than when this was followed by traditional approaches.
Table of Contents
Prevalence of CRPS
- Complex regional pain syndrome accounts for approximately 2–5% of adult.
- It affects females more, in a 3.5:1 ratio in adults.
- It approximately affects 5,000 Australians every year.
There is currently no singular aetiology (the causation agent) identified for the development of CRPS. It is most likely to be multifactorial and contributing to the chronic neuropathic pain with autonomic nerve dysfunction.
There are number of possible triggers, such as tissue injury, nerve damage, fracture, surgery, sprains, infections, etc. However, there are spontaneous cases of CRPS, with no known reason for the start of the disease.
The classical mechanism of CRPS comprises of four major pathways:
- Exaggerated inflammation – with cytokines, calcitonin, substance P, tissue factors, interleukins release at the site of initial trauma, leading to peripheral sensitisation
- Central reorganisation – with up regulation of dorsal horn receptors with wind up, development of central sensitisation and neruoplasticity, cultivating emotional changes, including neglects, anxiety and fear avoidance
- Sympathetic reflex dystrophy – hypothalamus-pituitary-adrenal glands imbalance, releasing circulating catecholamines, causing sympathetic afferent coupling with up regulation of adrenergic receptors
- Psychological and social implications
Recently, scientists have gained more understandings on the influences of CRPS, that it is indeed a multi-systemic disorder. The new model suggests dendritic cells could be the primary drivers of CRPS:
- Auto-inflammatory – activation of self innate immune response with the release of pro-inflammatory cytokines
- Auto-immunity – activation of adaptive immune response, which is driven by the dendritic cells, langerhans and mast cells in both nervous systems and circulatory systems
- Cortical reorganisation – distortion in spatial representation, neuroplasticity of sensory and motor cortex
- Basal ganglia dysfunction – neuroinflammation via the glial cells activation
Hence, with the complexity of the mechanism of CRPS, we should be tailor our treatment according to the mechanism:
Nocicpetive: inflammatory changes, e.g. acute swelling, redness
Neuropathic: nerve dysregulation, e.g. hypersensitivity, burning pain
Nociplastic: sensitised nervous system, e.g. significant pain on light touch
CRPS is a clinical diagnosis. It is categorised into four major signs and symptoms:
- Sensory changes – hyperalgesia (increased pain intensity from stimulus that normally causes pain), allodynia (pain from stimulus that does not provokes pain)
- Vasomotor changes – temperature differences (colder or warmer), skin colour changes (mottled, bluish, pale, redness)
- Sudomotor changes – swelling, stiffness, sweating
- Motor or Trophic changes – hair and nail changes, movement restriction, weakness
Scientific research has helped us to understand pain is a multidimensional dynamic experience with multiple brain sites activation. From localised muscle or nerve inflammation to neuroplasticity (ie. structural and chemistry changes of the nervous system) leading to emotional distress and behavioural changes.
Factors Associated With CRPS Development
No clear causation have been identified with the development of CRPS. However, there have been several factors suggestive the vulnerability of a person developing CRPS.
This include: female, older adult, high energy injury, severe comminuted distal radius fracture, ankle dislocation or intra-articular fracture, immobilisation, high pain intensity in early phases of trauma, social and psychological stresses.
The cognitive construct of a person also matters. This include challenging childhood experience, coping styles, cognitive beliefs, fears, sensitised nervous system, chronic insomnia and major life events.
Effects Of Persistent Pain
Biological: Heightened Pain, Cognitive Impairment, Sleep Disturbance, Physical De-Conditioning, Medication Over-Use, Suppression of immunity
Psychological: Depression, Anxiety, Post-Traumatic Stress, Learned Helplessness, Self-Harm
Sociocultural: Social Withdrawal, Dysfunctional Relationships, Isolation, Carer Stress, Vocational Role Interference, Financial Ramifications
Pain Treatment Options
It is no longer acceptable to apply single model fo care to everyone living with osteoarthritis related pain. It is best practice that treatment should be mechanism-based, symptom-based and disease-based. No two patients are alike, why should the treatment follow a strict algorithm? Treatment plans should be patient-centred with biopsychosocial strategy, with personalised approach in a stepped-care model.
The goal of the treatment is to promote resilience, healing, prevent and reduce pain chronification.
Common Treatment Options include (but not limited to):
- Patient Education
- Physical Activities
- Cognitive Modification
- Sociological Support
- Procedural Interventions
“Educational Interventions that aim to change one’s understanding of the biological processes that are thought to underpin pain as a mechanism to reduce pain itself” – Explaining Pain
Education is a powerful tool to help you to understand information about the different treatment approaches, information about the disease, about the pathophysiology, and about the diagnostic imaging.
Consistent recommendations for early management are that individuals should be provided with advice and education about the mechanism of CRPS; reassurance that early aggressive intervention is essential, and encouragement to avoid immobilisation, stay active, and continue with usual activities, including work.
Exercise therapy is particularly helpful in decreasing pain and improving joint motion. Research shows that a comprehensive programme tailored to individual needs is recommended. No one exercise programme is more superior or beneficial.
Recommended physical treatments, depending on the affected region, a physical therapist (such as hand therapist or physiotherapist) could provide desensitisation process with different materials, regular exposure to touch, graded motor imagery exercises, gradual stretching then strengthening affected region, to improve function and prevent worsening disability.
Cognitive Behavioural Therapy (CBT) is the most common psychological intervention. It consists of cognitive appraisal, restructuring beliefs, behavioural activation, problem solving and motivation. It helps people living with CRPS to conquer fears of moving and emphasise on exacerbation management.
If it is trauma related, specialised psychological therapy (such as Eye Movement Desensitisation and Reprocessing “EMDR” Therapy) can be adopted to mitigate the anxiety, intrusive thoughts, avoidant behaviour resulted from the injury.
CBT is not the only psychological treatment available. More advanced therapy also available to explore the dynamic cognitive process to facilitate sustained benefits for people with complex psychological construct.
The most often recommended in the guidelines include paracetamol and anti-inflammatories. Recent research from UNSW demonstrated paracetamol has no benefit in pain reduction. Topical or oral anti-inflammatories were shown to be effective for pain relief and for function.
Nerve medications are essential in CRPS treatment. It has established efficacy to reduce the neuropathic pain, especially the autonomic nerve dysfunction. Topical nerve medications are frequently used, to promote the localised absorption and desensitisation process. Nerve medications also enhance the descending modulatory systems (ie. the calming system from our brain).
Early aggressive treatment is important. Opioids might be used in a short term to enable early rehabilitation to prevent deconditioning and immobilisation. However, regular review is required to minimise the risk of aberrant use. If pain is severe and not responding to the conventional management, cautious selection of safer opioids with clear goals are essential.
Depending on the symptoms, mechanism and underlying pathology, procedural interventions could be very beneficial to facilitate functional gain. These include:
- Sympathetic nerve block with steroid injection: the common targets are Stellate Ganglion Block for upper limbs, or Lumbar Sympathetic Nerve Block for lower limbs
- Nerve-block with Radiofrequency Treatment: providing longer effect, especially for those who are resistant to nerve block with steroid injection only
- Neuromodulation: when there is refractory pain management from above procedures
- Intramuscular botulinum toxin injection: for those who have chronic CRPS with central motor symptoms and significant muscle spasticity
Amputation is regularly comes up for people living with long standing therapy resistant chronic CRPS. It is advised that all options should be explored for pain control and dysfunctional limb treatment before amputation is considered. The risks after amputation should be clearly informed, including the development of residual limb pain, phantom limb pain and neuropathic pain from the neuroma. Sometimes, people with CRPS are unable to tolerate the prosthesis due to persistent pain. The decision making process MUST involve in a multidisciplinary team care with pain specialist, rehabilitation physician, psychiatrist, physiotherapist or occupational therapist.
CRPS is a significant debilitating chronic primary pain problem that requires early diagnosis and early aggressive treatment. It is a multi-systemic health conditions that affecting the physical, psychological and sociological wellbeing of the person. Your treatment plans should be fast-tracked and tailored to your symptoms.
Dr Chow Chow provides remarkable collaborative system with Sydney top leading experts, this includes physical therapist and hand therapist trained in rehabilitation programme, pain psychologist, psychiatrist, rehabilitation physicians.
Have any questions about how to manage your back pain? Contact email email@example.com
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- Pons T, Shipton EA, Williman J, Mulder RT. Potential risk factors for the onset of complex regional pain syndrome type 1: a systematic literature review. Anesthesiol Res Pract. 2015;2015:956539.
- Abbott-Fleming V. Is Amputation for CRPS really a cure? https://www.burningnightscrps.org/is-amputation-for-crps-really-a-cure/