What Is Complex Regional Pain Syndrome (CRPS)?

Complex regional pain syndrome is a chronic neurological condition that typically affects one or more limbs — usually an arm or leg — following an injury, surgery, or other triggering medical event. It is characterized by disproportionate, intense pain that far exceeds what would normally be expected from the original injury. CRPS is divided into two subtypes: CRPS-I (formerly called reflex sympathetic dystrophy), which occurs without confirmed nerve injury, and CRPS-II (formerly called causalgia), which follows a confirmed nerve injury.

CRPS is widely considered one of the most painful chronic conditions known to medicine. Without prompt and appropriate treatment, symptoms can worsen significantly over time. Early intervention at a specialized pain management practice like Olympus Spine and Pain gives patients the best opportunity for meaningful recovery.

What Are the Symptoms of Complex Regional Pain Syndrome?

CRPS typically causes a distinct and recognizable pattern of symptoms in the affected limb. The most common is an intense burning pain or a distressing pins-and-needles sensation. Additional symptoms can include:

• Extreme sensitivity to light touch (allodynia)
• Local swelling and puffiness in the affected limb
• Skin temperature changes — the limb may feel unusually hot or cold
• Skin color changes — ranging from pale to red or mottled purple
• Skin texture changes — becoming shiny, thin, or unusually dry
• Abnormal hair and nail growth in the affected area
• Excessive sweating or absence of sweating in the limb
• Joint stiffness and reduced range of motion
• Muscle weakness and tremors

In rare cases, some patients experience “mirror” pain — identical symptoms appearing in the opposite limb. The progression and severity of CRPS varies from person to person, which is why personalized care is so essential. If you are also experiencing neuropathy and foot pain or symptoms in your upper extremities alongside CRPS, Dr. Warner will assess all contributing factors comprehensively.

What Causes Complex Regional Pain Syndrome?

The majority of CRPS cases begin with trauma to a limb — such as a wrist fracture, a cut, burn, sprain, or strain. CRPS can also develop after surgery, a heart attack, or a prolonged period of limb immobilization (such as wearing a cast). The trauma triggers damage to the peripheral C-fibers — the nerve fibers responsible for transmitting pain signals to the brain. When these fibers malfunction, they begin to “fire” excessively, generating ongoing inflammation, pain, and the constellation of symptoms described above.

In some cases of CRPS, there is no clearly identifiable source of nerve damage. This makes diagnosis challenging and underscores the importance of seeing a physician with specialized training in chronic pain conditions. Dr. Warner’s extensive background in interventional pain medicine — including his fellowship training at MD Anderson Cancer Center — equips him to assess even the most complex presentations.

How Is Complex Regional Pain Syndrome Treated?

At Olympus Spine and Pain, Dr. Warner offers a comprehensive, multimodal approach to CRPS treatment. Because the condition affects the nervous system in complex ways, effective treatment typically involves several strategies working together. Options may include:

• Physical therapy to improve movement, strength, and desensitization
• Oral medications to manage pain and reduce nerve hypersensitivity
• Corticosteroid injections to reduce inflammation
• Nerve block injections to interrupt pain signaling
• Spinal cord stimulation (SCS) — an implantable device shown to be highly effective for CRPS
• Peripheral nerve stimulation
• Intrathecal drug pump for sustained medication delivery
• Ketamine infusions* for patients with refractory CRPS
• Scrambler Therapy — a non-invasive neuromodulation technique that retrains the nervous system’s pain response

Dr. Warner stays at the forefront of CRPS research and treatment innovations. He takes the time to explain all available options, helping each patient understand the rationale behind their recommended plan. The overarching goal is to reduce pain to a level that allows you to participate fully in physical therapy, resume daily activities, and regain your quality of life.

*Ketamine infusions are FDA-approved as a sole anesthetic agent for diagnostic and surgical purposes, but are not yet approved for chronic pain treatment. Spravato®, an esketamine nasal spray, has FDA approval for addressing treatment-resistant depression.

Complex Regional Pain Syndrome — Frequently Asked Questions