Complex regional pain syndrome (CRPS) is a regional neuropathic pain syndrome that usually develops within a few weeks after limb trauma or surgery. CRPS presents with symptoms and exam findings that can be categorized as follows: sensory, vasomotor, sudomotor, and motor/trophic changes. CRPS is diagnosed clinically using the Budapest criteria. No specific test or imaging study can rule in or rule out CRPS; however, MRI and triple-phase bone scan may show findings suggestive of CRPS. Two subtypes of CRPS are currently accepted: CRPS type I occurs without peripheral nerve injury; CRPS type II occurs with peripheral nerve injury. Effective treatment is often difficult, and therefore requires a multidisciplinary approach, individualized to the patient. The goal of all therapies is to improve function and relieve pain. Evidence suggests vitamin C supplementation after distal limb fracture or surgery may reduce the risk of developing CRPS. Conservative therapy should be started first, and may include various oral medications (e.g., NSAIDs, gabapentin, clonidine), corticosteroid injections, and physical therapy, and psychotherapy. More advanced therapies are relatively new, have little supporting evidence, and should be pursued with appropriate specialty consultation. These include regional sympathetic blockade, ketamine infusion, neuromodulation, and surgical sympathectomy. Prognosis is variable, but most cases resolve within a few months to a year with appropriate treatment. Delayed diagnosis and inadequate therapy are associated with prolonged recovery. Approximately 10-20% of cases become chronic and refractory to any therapy.
|G90. 511||CRPS type I upper limb, right|
|G90.512||CRPS type I upper limb, left|
|G90.521||CRPS type I lower limb, right|
|G90.5322||CRPS type I lower limb, left|
|G56.41||Causalgia (CRPS type II) upper limb, right|
|G56.42||Causalgia (CRPS type II) upper limb, left|
|G57.71||Causalgia (CRPS type II) lower limb, right|
|G57.72||Causalgia (CRPS type II) lower limb, left|
Complex regional pain syndrome (CRPS) is a regional neuropathic pain that does not follow the usual distribution of a dermatome or nerve territory.
Associated with abnormal sensory, autonomic, motor, and/or trophic changes
Most commonly develops after distal limb trauma or surgery
CRPS diagnosed clinically using the Budapest criteria, which was approved by International Association for the Study of Pain (IASP) in 2012
Usually occurs 4 to 6 weeks after inciting event
Risk factors: female, postmenopausal, recent distal radius fracture, ankle dislocation and/or intra-articular fracture, immobilization, high levels of reported pain after trauma
Pain is commonly felt deep within the limb and is described as burning, searing, or shooting; worsens with movement, contact, temperature variation, and stress.
Four symptom categories: sensory, vasomotor, sudomotor/edema, motor/trophic ( Table 23.1 )
Clinical Categories of Signs and Symptoms
Continuing pain, which is disproportionate to any inciting event
Sensory—hyperalgesia, hypoesthesia, allodynia
Vasomotor—skin color or temperature changes/asymmetry
Sudomotor/edema—edema and/or sweating changes and/or sweating asymmetry
Motor/trophic—decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
Must report at least one symptom in three of the four clinical categories
Must display at least one sign at the time of assessment in two or more of the four clinical categories
There is no other diagnosis that better explains the signs and symptoms
Inspect area carefully and compare findings with contralateral limb (see Table 23.1 ).
Observe gait and posture for any compensatory movements and guarding.
Inspect extremity for edema, changes in hair/nail growth, and skin color/appearance.
Assessment of skin temperature, tone, and texture.
Evaluate range of motion, strength, and reflexes.
Neurologic: pinprick, light touch, temperature, deep somatic pressure.