Hand surgeon offers tips for identifying and managing complex regional pain

Surgery is indicated for unresponsive and sympathetically maintained, acute patients.

Issue: February 2007

The prognosis of improvement for patients with complex regional pain syndrome drops 30% if they are diagnosed 1 year after onset, making diagnosis and treatment critical.

At the American Society for Surgery of the Hand 61st Annual Meeting, L. Andrew Koman, MD, an orthopedic surgeon at Wake Forest University Baptist Medical Center, Winston-Salem, N.C., offered diagnosis guidelines and discussed treatment options for complex regional pain syndrome (CRPS).

"The key is to determine if they're independent vs. sympathetically maintained, state and address any nociceptive foci, and to develop a treatment plan," Koman said during his presentation.

There are two types of CRPS or reflex sympathetic dystrophy, he said. Type 1 CRPS is traditional reflex sympathetic dystrophy (RDS), while patients with Type 2 CRPS have an associated nerve injury or causalgia. Physicians further distinguish the condition as sympathetically maintained pain (SMP) or sympathetically independent pain (SIP).

Although the FDA has not approved any oral medication for CRPS, Koman noted that patients with SMP can experience pain relief through sympathetic interventions such as phentolamine, cervical epidurals or axillary blocks.

The clinical definition of CRPS includes pain and autonomic dysfunction, atrophic/trophic changes and functional impairment. The condition is marked by decreased function long after injury.

"This is not an aberration of people; this is an aberration of the time course," Koman said. "It is the abnormal prolongation of a normal post-traumatic response."

Nearly half of patients with the condition have an identifiable nociceptive event with neural or mechanical injury, he said. Koman also noted that distal radius fracture "is one of the most common injuries now which produces reflex sympathetic dystrophy."

Diagnosis

Patients with an acute CRPS will report burning, tearing, severe numbness and mild to moderate edema.

Diagnosing indolent patients can prove problematic, Koman said. These patients can later develop stiffness, atrophy and nonunion.

"These are unfortunate patients who just don't do well," he said. "They have problems sleeping. If you're only going to ask your patients one question, ask them if they can sleep, because if they can sleep at night, they probably don't have CRPS."

Physicians should also note psychiatric conditions masquerading as CRPS.

"Beware of the massive edema, clenched fists [or] spread that is not related to additional trauma, as well as chronic blisters and sores. All of these can be fictitious or psychiatric problems," Koman said.

While some believe that the condition is psychiatrically manifested, no literature has shown psychological causation, he added. X-rays of the condition will show diffused demineralization and nonspecific subchondral osteoporosis.

Koman cited research by Bickerstaff, which showed cortical, subchondral and cancellous bone loss in patients with RSD fractures using quantitative scintigraphy. While these tools can prove beneficial, Koman highlighted a literature review of 19 studies performed by G.W. Lee, who cautioned against using three-phase bone scintigraphy as a major diagnosis criterion.

Treatment

Once a diagnosis is made, physicians can use multiple treatment approaches, including pharmaceutical and surgical interventions.

"Nonoperative treatment is still the primary option, and sympatholytic drugs, along with therapy, are appropriate early," Koman said.

He uses amitriptyline for patients with a high total flow and nutritional deprivation, and calcium channel blockers for those with low total flow. He gives clonidine to high-total-flow patients with edema and hyperalgesia.

Koman, who noted that stress loading can decrease edema, highlighted the role of continuous blocks such as cervical and lumbar epidurals.

"In the acute patient who is not responding, we may need to address the nociceptive or mechanical or neural foci," Koman said. "And it is appropriate to perform surgery if he or she is not responding."

He cited a study by Jesse Jupiter, MD, which showed that surgery was safe and efficacious in nine acute cases of causalgia.

"In acute CRPS with median nerve symptoms that are unresponsive to medical management and are able to be controlled with continuous block, early neurolysis is appropriate," Koman said.

Chronic conditions

For patients with chronic conditions, surgeons should relieve neural or mechanical nociceptive foci and correct deformity with capsulectomy, osteotomy and debridement.

"Neuropathic pain can be managed by neurolysis, repair and/or environmental modification," Koman said. "And it is safe and appropriate. You can control the pain with very few exacerbations. And in our experience of over 300 patients ... operated on after the diagnosis, none were made worse."

Dural column stimulators have a role in the late management of CRPS, and amputation should be avoided unless patients have an infection, he said.

For more information:
Koman LA. Current management of chronic regional pain syndrome. Precourse 6. Presented at the American Society for Surgery of the Hand 61st Annual Meeting. Sept. 7-9, 2006. Washington.
L. Andrew Koman, MD, Wake Forest University Health Sciences, dept. of orthopedics, Medical Center Blvd., Winston-Salem, NC 27157; 336-716-4015; lakoman@wfubmc.edu.