Complex Regional Pain Syndrome: Symptoms, Causes & Treatment

Complex regional pain syndrome is a chronic pain condition that typically develops after an injury or a surgical procedure. Also known as CRPS, this disorder is identified by intense pain that feels much worse than what would normally be expected from the original trauma.

Most cases are classified as post-traumatic CRPS, appearing after a bone fracture, a severe sprain, or a period of restricted movement. The condition often involves noticeable swelling, changes in skin texture, and a gradual loss of joint mobility in the affected limb.

Successful management of this syndrome depends on early intervention through a combination of physical therapy and specialized pain relief. Consulting a specialist is highly recommended to create a tailored treatment plan and prevent the symptoms from becoming a permanent disability.

Main symptoms

Complex regional pain syndrome is primarily characterized by the following clinical signs:

• Constant, intense pain that seems out of proportion to the injury

• Burning or "pins and needles" sensations

• Extreme sensitivity to even light touch or cold temperatures

• Swelling in the affected arm or leg

• Noticeable changes in skin color, temperature, or texture

• Joint stiffness and a decreased range of motion

These symptoms usually emerge within a few weeks of the initial injury and are concentrated in the affected area.

Symptoms by location

Depending on where the syndrome develops, patients may experience specific functional challenges:

• CRPS of the foot or ankle: Significant pain when putting weight on the foot, difficulty walking, and persistent swelling.

• CRPS of the knee: Limited ability to bend or straighten the leg, pain during any movement, and stiffness.

• CRPS of the hand or wrist: Loss of grip strength, pain when touched, and difficulty picking up or holding objects.

Despite these location-specific issues, the core symptoms of the condition remain consistent, primarily involving localized pain and inflammation.

Phases of complex regional pain syndrome

Medical professionals generally describe the progression of this condition in three distinct stages:

• Acute phase: This is the inflammatory stage marked by intense pain, swelling, and skin that feels warm or looks red.

• Dystrophic phase: This occurs as the joint "cools down," leading to pale or bluish skin, increased stiffness, and constant pain.

• Atrophic phase: This chronic stage happens when the condition is left untreated, resulting in permanent loss of function and skin changes.

Because of this progression, seeking medical help early is vital to improve the long-term outlook and reduce the risk of permanent physical damage.

How to confirm a diagnosis

A diagnosis of complex regional pain syndrome is mainly based on a physical exam and a review of symptoms following a trauma or surgery.

Based on guidelines from the National Institute of Neurological Disorders and Stroke (NINDS), doctors typically use the Budapest Criteria to evaluate patients, which helps them categorize symptoms into groups like sensory changes, blood flow issues, and motor dysfunction

There is no single laboratory test that can definitively prove someone has CRPS. However, doctors may order X-rays to check for bone mineral loss or use an MRI or a bone scan to rule out other underlying health conditions.

Main causes

The primary factors that usually trigger the onset of complex regional pain syndrome include:

• Fractures, sprains, or significant limb trauma

• Surgery, especially orthopedic procedures on the extremities

• Long periods of immobilization, such as being in a cast

• Peripheral nerve damage

• Certain underlying neurological disorders

In some instances, however, the exact cause of the syndrome cannot be identified by medical professionals.

Treatment options

The goals of treating complex regional pain syndrome are to manage pain levels and restore the full use of the affected limb. Common treatment paths include:

1. Rehabilitation and physical therapy

Physical therapy is arguably the most critical part of recovery because it prevents permanent stiffness. A therapist will guide the patient through:

• Gentle and progressive movement exercises

• Workouts tailored to the specific joint (hand, ankle, or knee)

• Training to improve walking, weight-bearing, or grasping objects

Progress is made at a pace the patient can handle, focusing on restoring function without causing the patient to fear moving the limb.

2. Medications for pain and inflammation

Doctors may prescribe various medications to lower pain levels so the patient can participate more effectively in physical therapy. Options include:

• Over-the-counter pain relievers like acetaminophen

• Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen

• Corticosteroids, like prednisolone, for specific short-term needs

• Prescription opioid analgesics, such as tramadol, for moderate to severe pain

All medication use must be supervised by a healthcare provider, as side effects and effectiveness vary significantly between patients.

3. Muscle relaxants for spasms

If the condition causes significant muscle tension or painful spasms, a doctor might suggest a short-term muscle relaxant.

US-based examples of these medications include:

• Cyclobenzaprine

• Baclofen

These drugs are not appropriate for everyone and require a professional medical consultation due to potential side effects.

4. Specialized pain management

If pain remains debilitating despite standard therapy and medication, a referral to a pain management clinic may be necessary.

Advanced options may include:

• Sympathetic nerve blocks to interrupt pain signals

• Interventional procedures performed by specialists

These treatments are not used for every patient and are decided on a case-by-case basis depending on how the patient has responded to previous attempts.

5. Braces and functional aids

A temporary brace or orthotic might be used to stabilize a joint or provide relief during a painful flare-up.

The long-term goal is always to avoid keeping the limb still for too long, as recovery depends on getting the area moving again.

Is it possible to recover from complex regional pain syndrome?

Recovery is definitely possible, especially when treatment begins shortly after the symptoms first appear.

However, some cases can transition into a permanent condition with limited mobility. The final outcome usually depends on how quickly treatment started and how well the body responds to the various therapies.

How to prevent it

While not always avoidable, certain steps can reduce the risk of developing CRPS after an injury or surgery.

Prevention strategies include:

• Beginning gentle movements as soon as medically cleared after an injury

• Reporting any unusually intense or "wrong" feeling pain to a doctor immediately

• According to the American Academy of Orthopaedic Surgeons (AAOS), taking Vitamin C supplements after certain orthopedic injuries, such as wrist fractures, may help reduce the risk of developing the condition when recommended by a surgeon.

These steps should be tailored to your specific health history. If you notice any signs of CRPS, it is essential to consult a doctor right away to start treatment as soon as possible.