- Reflex sympathetic dystrophy (RSD)
- Reflex neurovascular dystrophy (RND)
- Amplified musculoskeletal pain syndrome (AMPS)
- Disorder of the extremities characterized by regional pain that is disproportionate in time or degree to the usual course of any known trauma or other lesion
- Pain is not in a specific nerve territory or dermatome
- Pain usually has a distal predominance of abnormal sensory, motor, sudomotor, vasomotor, and/or trophic findings
- CRPS often worsens over time
- 35% of patients report symptoms throughout their whole body.
||NO evidence of peripheral nerve injury (edema, erythema, numbness), 90% of clinical presentations
||YES evidence of peripheral nerve injury, considered more serve type
- Generally unknown
- Inciting event
- Found in about 90% of cases - usually begin 4-6wks after fractures, crush injuries, sprains, and surgery.
- Proposed mechanisms
- Classic inflammation, neurogenic inflammation, and maladaptive changes in pain perception at the level of the central nervous system
Type II CRPS showing skin changes
||burning, stinging, or tearing sensation that is felt deep inside the limb, usually continuous but can be paroxysmal.
||hyperalgesia, allodynia, or hypesthesia
||weakness, occasional tremor, myoclonus, or dystonic postures
||warmth, skin color changes, sweating, or edema, other skin/hair/nail changes
Clinical: Budapest consensus criteria:
At least 1 symptom in three of the following four categories:
||temperature asymmetry, skin color changes, skin color asymmetry
||decreased ROM, weakness, tremor, dystonia, trophic changes (hair, nail, skin)
- And, there is no other diagnosis that better explains the signs and symptoms
Rule-Out Emergent Etiologies
- CT/MRI/XR are all NOT diagnostic for CRPS
- Initial bolus - 0.2–0.3 mg/kg of infused over 10mins.
- Avoid IV push - could cause dissociative side effects.
- Diagnostic- pain should resolve by the end of the 10min bolus and if so, continue
- Infusion - 0.2 mg/kg/hr over 4-6hrs.
No discharge prescription usually required. If needed:
Opioids should NOT be used for chronic or acute CRPS. Patient education on this is important.
- Outpatient follow-up with pain management
- Referral for PT/OT - important for all CRPS patients
- Consider psychiatric referral if warranted
Acute pain management
- ↑ Schwartzman RJ, Erwin KL, Alexander GM (May 2009). "The natural history of complex regional pain syndrome". The Clinical Journal of Pain. 25 (4): 273–80. doi:10.1097/AJP.0b013e31818ecea5. PMID 19590474.
- ↑ Sandroni P, Benrud-Larson LM, McClelland RL, Low PA. Complex regional pain syndrome type I: incidence and prevalence in Olmsted county, a population-based study. Pain 2003; 103:199.
- ↑ 3.0 3.1 Ducharme, Jim, MD. "Tips for Managing Complex Regional Pain Syndrome - ACEP Now." ACEP Now. N.p., 11 Sept. 2015.
- ↑ 4.0 4.1 4.2 Birklein F, O'Neill D, Schlereth T. Complex regional pain syndrome: An optimistic perspective. Neurology 2015; 84:89.
- ↑ Harden RN, Oaklander AL, Burton AW, et al. Complex regional pain syndrome: practical diagnostic and treatment guidelines, 4th edition. Pain Med 2013; 14:180.