Complex Regional Pain Syndrome or CRPS: What we need to know

Complex regional pain syndrome (CRPS) is a chronic persistent painful condition. The pain is very severe and debilitating and usually affects arms, legs, hands, or feet. The condition commonly develops because of a soft tissue injury, sprain, stroke, or heart attack. Doctors believe that CRPS is a kind of nerve pain due to the dysfunction of the brain, spinal cord, or nerves. The dysfunction causes over-reaction to small pain stimuli. Hence, the condition is also known as reflex sympathetic dystrophy syndrome.

Causes of CRPS

The exact cause of CRPS is still unknown. It develops due to a soft-tissue injury, sprain or strain, surgery, stroke, infections, or a heart attack. CRPS may result from a combination of many factors, such as:

• General inflammation in the region
• Abnormal immune response in the affected region
• Inaapropriate sensitivity of the pain receptors
• Abnormal pain perception by the brain

Many factors determine whether someone would develop CRPS or not. For example, genetics, type of injury, region involved, and inappropriate inflammatory or immune response.

Symptoms of CRPS

In case you have complex regional pain syndrome, you would experience the following symptoms:

• Persistent throbbing or burning pain that worsens over time
• Warmth, redness, swelling of the affected region
• Sensitivity to touch, heat, and cold
• Changes in skin color, temperature, and texture
• Changes in hair and nail growth
• Joint stiffness, muscle spasm, and weakness
• Difficulty moving the affected body part

Diagnosis of CRPS

It isn’t easy to make the diagnosis of CRPS, but the following provide clues to the doctor:

• Medical History: Your signs and symptom give important clues about your condition. Your doctor will also ask you about any previous injury, surgery, or other significant event relating to your health.
• Physical examination: Your doctor will palpate the affected region to check for pain, temperature and texture changes, and other associated symptoms.
• Specific tests such as bone scans, X-rays, and sweat production tests help identify changes in the affected region and rule out other conditions.
• The doctor may confirm the diagnosis with a sympathetic nerve block.

Prognosis of CRPS

Complex regional pain syndrome has no cure. The treatment options only help control the symptoms and perform daily activities. Many treatment options are available for this purpose, and it may take time to make an effective treatment combination.

Treatment of CRPS

Your doctor will recommend a combination of the following treatment options:

• Over-the-counter pain relievers: OTC pain relievers such as naproxen and aspirin help relieve pain and inflammation temporarily.
• Prescription pain relievers: Your doctor will prescribe more potent medicines when OTC pain-relievers don’t relieve pain. These include opioids (codeine), antidepressants (amitriptyline), and anticonvulsants (gabapentin) and treat neuropathic pain.
• Topical agents like capsaicin cream may help reduce sensitivity.
• Corticosteroids: These may improve inflammation and improve mobility, i.e., prednisone.
• Applying ice and heat alternatively to the affected area
• Physical therapy helps improve mobility of the affected joint and the other regions.
• Mirror therapy and other brain desensitizing therapies to reduce pain perception

Interventional Pain Management

If your pain does not respond to these treatment options, your doctor may recommend interventional pain management. It utilizes various pain-blocking techniques to help perform daily activities. These options include:

• Sympathetic nerve blocks: Sympathetic blocks like stellate ganglion block for hand and lumbar sympathetic block for legs have an essential role in treating CRPS.
• Your doctor may use an anesthetic to block nerve fibers that carry pain impulses to the brain. Continuous brachial plexus block, continuous epidurals have essential roles.
• Intrathecal drug pumps: These pumps deliver pain-relieving medications into the spinal cord.
• Transcutaneous electric nerve stimulation (TENS): In TENS, electric stimulation of the nerve fibers stops nerve transmission and relieves pain.
• Spinal Cord stimulation: Your doctor may also recommend stopping nerve impulse transmission in the spinal cord using tiny electrodes.
• Surgery: It is the last resort in the past, and its use was controversial. In a surgical intervention, a surgeon resects the sympathetic nerves involved in pain transmission to relieve pain. But with the advent of percutaneous radiofrequency and cryoablation techniques, surgical sympathectomies are obsolete.