Complex Regional Pain – What are the Features?

Criteria for Complex Regional Pain sydrome may be being relaxed with perhaps only 2 features being necessary and only 1 feature needing to be visible at any time.

The diagnosis of Chronic Regional Pain can be difficult though pain well out of proportion to what it should be would be a goood tip off.
At the IASP congress Montreal it was discussed:
Budapest clinical diagnostic criteria for CRPS

1) Continuing pain, which is disproportionate to any inciting event

2) Must report at least one symptom in three of the four following
• Sensory: reports of hyperesthesia (excessive tenderness) and/or allodynia (pain on light touch and/or deep somatic pressure and/or joint movement) – example was  (have them rate from 0-10)
– “;”>lightly stroking the skin proximally to distally at the midforearm, quadriceps, and gastrocnemius muscles.”
– “palpation at the first metacarpophalangeal joint of the hand and the first metatarsophalangeal joint of the foot”- for deep somatic pressure
Cold sensitivity –  response to the steel handle of a reflex hammer or tuning fork

• Vasomotor: reports of temperature asymmetry and/or skin color changes and/or skin color asymmetry

I have used a simple alcohol thermometer:

You can get the from various places but unfortunately they want you to buy 100 at a time…
http://bio-medical.com/product_info.cfm?inventory__imodel=BF199
http://biofeedbackcentral.com/products/bf199.html

With the cold allodynia form, the difference in limb temperature will be 0.6°C = 1.08° F (at least in fahrenheit it is a whole degree)

Note – Only use it when your hands are in a stable environment – not when you have just come in from outdoors, or you have been exercising and so on;  Tape it down to you finger with tape.  Read the fahrenheit scale as it is more sensitive to changes. Use the same thermometer for both sides as each thermometer might be off a bit.

Rate muscle weakness, spasm, dystonia, tremor, edema, and hyperhidrosis (sweating) from 0-4:
• Sudomotor/edema: reports of edema and/or sweating changes and/or sweating asymmetry

This is going to vary from day to day and best photographed on a good day for records

• Motor/trophic: reports of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
3)  Must display at least one sign at time of evaluation in two or more of the following categories:
• Sensory: evidence of hyperalgesia (to pinprick) and/or allodynia (to light touch and/or deep somatic pressure and/or joint movement)
• Vasomotor: evidence of temperature asymmetry and/or skin color changes and/or asymmetry
• Sudomotor/edema: evidence of edema and/or sweating changes and/or sweating asymmetry
• Motor/trophic: evidence of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)

This is important – not all features are going to be present at one time – insurers will try to play a problem down because they are not all there at once but that is just fraud… Please keep photographs of the problem when other manifestations are evident.

4) There is no other diagnosis that better explains the signs and symptoms

A Japanese study has thrown doubt over the need for three features:
Pain. 2010 Aug;150(2):243-9. Epub 2010 May 6.
Development of comprehensive diagnostic criteria for complex regional pain syndrome in the Japanese population.
Sumitani M, Shibata M, Sakaue G, Mashimo T  abstract here

and Bruehl has suggested two might be enough in some cases:
Pain. 2010 Aug;150(2):217-8. Epub 2010 May 18.
Modifying diagnostic criteria for Complex Regional Pain Syndrome
Bruehl S. no abstract

What is important to remember is that of these feature, only one needs to be seen and the other could have occurred prior (for example the affected limb can get hot before it over time,  turns to the cold side) – document these and photograph…