Complex regional pain syndrome (algodystrophy)

Complex Regional Pain Syndromes type 1 or 2 (former algoneurodystrophy and causalgia)

Description..

CRPS can evolve in 3 phases:

The evolution between these 3 phases is variable in duration and can be very long or not exist (passage to phase 2 directly for example).

Phase 1 (warm phase):

– Spontaneous and induced pain, severe and intense.
– Increased sensitivity of the skin to touch and light pressure (hyperesthesia).
– Localized edema, muscle cramps, stiffness and limited mobility of the affected joint.
– The skin is usually hot, red, moist and shiny, there is an increase in sweating.

algo main

Phase 2 (cold phase):

– Spontaneous pain becomes less intense but more severe on mobilization, more diffuse.
– The skin takes on a bluish (cyanic) appearance and may become cold.
– The edema tends to spread and can change from a rather soft type to hard.
– The hairs may become thicker but not numerous.
– The nails become brittle, cracked and present important furrows.
– Amyotrophy (muscle wasting) is observed.

Phase 3 (Sequelae Phase):

– Tissue atrophy sometimes becomes irreversible associated with tendon retractions and/or joint capsules resulting in vicious attitudes and clear limitations of joint amplitudes.
– This phase is by no means mandatory and can be prevented by physiotherapy.

Causes (etiologies)

They are multiple and sometimes minimal:
– for CRPS type 1 (algodystrophy) any painful trauma (shock, surgery, wound,),
Stroke, brain or spinal cord injury, visceral damage (myocardial infarction for example
– for CRPS type 2 an initial nerve injury is necessary (wound or surgery)

The limit between these 2 forms is not clear.

Mechanism of occurrence

Very poorly known. Probably a dysregulation of the peripheral nervous system (nerves) but also central (spinal cord, brain). This deregulation is variable depending on the patient and gives very variable forms of CRPS with predominantly muscular forms, predominantly neurological forms or even purely central forms (rare) with complete paralysis of part of a limb.

Diagnostic

– It is essentially clinical: the history of the appearance of the pathology and the observation of the state of the affected part.
– Complementary examinations are only orientation elements, they make it possible to eliminate another pathology.
– X-rays sometimes find signs of speckled osteoporosis in the affected area.
– Bone scintigraphy often finds changes in blood flow in the bone of the affected region depending on the hot or cold phase of the pathology.
– The MRI also finds bone changes related to the pathology.
– Functional neurological examinations (electromyogram) are normal.

To make the diagnosis it is recommended to use the Budapest criteria (Lille Recommendations, SFETD Congress 2017):

Budapest criteria

4 categories of symptoms and signs :

  • Sensitive: hyperesthesia, allodynia, hyperalgesia
  • Vasomotors: temperature asymmetry, color changes
  • Sudomotor/edema: edema, change in sweating
  • Motor/trophic: reduced range of motion, weakness, dystonia, tremors, trophic disorders (skin, nails, hair)

The diagnosis of CRPS can be confirmed by:

  • Continuous pain, disproportionate to any triggering factor.
  • At least one symptom from 3 of the 4 categories described
  • At least 1 sign among 2 of the 4 categories

Treatment

Prevention

  • It is not particularly recommended to use locoregional anesthesia rather than general anesthesia to prevent the onset of CRPS (Lille Recommendations, SFETD Congress 2017)

Curative

  • Respect for non-pain is no longer recommended (Recommendations of Lille, SFETD congress 2017). Early rehabilitation with exercises whose intensity is regulated so as not to aggravate the symptoms for a long time.
    • Progressive mobilization of the affected limb
    • As normal use as possible of the affected limb during daily activities
    • Massages, desensitization techniques
    • functional rehabilitation:
      • It should be as early as possible
      • carried out by a city physiotherapist if standard, by a multidisciplinary center in the most serious cases
      • include analytical and varied exercises whose intensity is adjusted to avoid aggravation of the patient.
      • Must offer training in pain management at home (relaxation, division of daily activities).
    • The following therapies may be offered to the patient in combination with the rehabilitative treatment:
      • A trial of visual feedback therapy with mirrors (mirror therapy)
      • A trial of sensory discrimination training therapy.
      • A trial of therapy by graduated exposure to the patient’s activities perceived as dangerous, when he presents a high level of fear-avoidance.
  • Scottish Baths (protocol) are not recommended (Lille Recommendations, SFETD 2017 Congress) (lack of literature on the subject).
  • Manual lymphatic drainage is not recommended (Lille Recommendations, SFETD Congress 2017)
  • Prolonged immobilization is to be avoided (Recommendations of Lille, SFETD congress 2017)
  • Psychological support recommended when:
    • request for care expressed seems inadequate
    • Existence of a dispute or procedure, seeking compensation
    • Contact phobia
    • associated mood disorders
    • State of post traumatic stress and/or traumatic bodily experience
    • Major impact on quality of life: desocialization, disorganization of affective life, etc.
    • Presence of suicidal comments or behavior
    • Associated psychiatric disorders
    • Suspicion of factitious disorder
    • Suspicion of somatization of a mental disorder
  • Calcitonin, which was very fashionable for a while, did not prove its effectiveness and lost its marketing authorization in France recently for the treatment of CRPS and is not recommended (Recommendations from Lille, SFETD congress 2017)
  • Recommended analgesic treatments include paracetamol and level 2 analgesics (codeine, tramadol, opium), however, NSAIDs, corticosteroids and strong opioids are not recommended (Lille Recommendations, SFETD Congress 2017)
  • It is recommended to use, when there are significant sensory signs, antiepileptic treatments (pregabalin, gabapentin) and/or tricyclic and related antidepressants (Lille recommendations, SFETD congress 2017). See articles on the treatment of neuropathic pain.
  • Some patients would have benefited from treatment with Ketamine, Lidocaine IV, botulinum toxin. For these treatments, no recommendations can be made due to a lack of data concerning efficacy, tolerance, dosages to use (Lille recommendations, SFETD congress 2017)
  • Some patients are treated with bisphosponates.
    • The recommendations of Lille, SFETD 2017 congress specifies:
      it is recommended to consider a single course of bisphosponates (pamidronate) in CRPS under the following conditions:

      • CRPS evolving for less than 1 year.
      • Positive technetium bone scan showing bone hyperactivity.
      • after having carried out an oral check-up and the necessary care.
      • the treatment is carried out within a multidisciplinary care and a physical care.
  • Topical treatments:
    • Capsaicin (Qutenza) has not been evaluated (problem of tolerance when applying???)
    • Versatis (5% lidocaine plaster) has not been evaluated but can be tried given its safety (Lille recommendations, SFETD congress 2017).
  • Some patients benefit from sympathetic block (after placement of a tourniquet at the root of the affected limb injection of a vasodilator or local anesthetic into a vein at the end of the affected limb). this technique is no longer recommended (Lille Recommendations, SFETD Congress 2017)
  • In some cases, locoregional anesthesia of the affected limb for several days associated with twice-daily physiotherapy gives good results. This technique was not mentioned during the Lille congress of the SFETD 2017.
  • Some teams set up electrical spinal stimulation which can give good results. The patient will have previously tried cutaneous neurostimulation. During the Lille 2017 consensus conference: This technique can be used after 1 year of development, after evaluation by a multidisciplinary team when the predominant pain component is neuropathic.
  • Rare patients have benefited from the implementation of electrical stimulation of the cerebral cortex after positive transcranial magnetic neurostimulation tests.
  • The use of intrathecal Baclofen is not recommended in this pathology (Recommendations of Lille, SFETD 2017 congress).
  • Non-invasive techniques are also offered in some centers such as hypnosis (not mentioned in the recommendations)

In the event of failure of the treatments and in particular of the locoregional anesthesia, the doctors must carefully seek a cause of treatable residual pain which maintains the CRPS…

A common and little known cause of maintenance of CRPS is a painful skin and/or subcutaneous scar. This pathology is a cicatricial neuropathy for which you will find the treatment in the article concerning it.
In this case the treatment of the cicatricial neuropathy may be sufficient. In case of failure, the association of the treatment of the cicatricial neuropathy with a locoregional anesthesia increases the chances of recovery.

 

Post operative chronic pain