Complex Regional Pain Syndrome (CRPS) is a broad term to describe chronic pain and inflammation centralized in the arm or leg. CRPS can develop after some form of trauma, like surgery, a heart attack, a stroke or an injury. A marked characteristic of the syndrome is the pain being disproportionate to the intensity of the initial trauma.
While CRPS is relatively uncommon and the cause is still being understood, it is best to start treatment early if symptoms of the syndrome are experienced. This article will discuss the symptoms, possible causes, prevention, treatment and more.
Symptoms of Complex Regional Pain Syndrome
The symptoms of CRPS can vary from person to person. While some individuals have several symptoms on this list, others may only experience one or two. Symptoms that are present can improve with treatment.
Signs of symptoms include:
- Inflammation of the affected area.
- Perpetual throbbing or burning, typically in the arm, hand, leg or foot.
- Extreme sensitivity to touch or cold.
- Joint stiffness, inflammation and trauma.
- Muscle weakness, spasms, tremors.
- Decreased mobility in the affected area.
- Changes in skin color—red, blue or blotchy.
- Changes in skin temperature—cold and clammy.
- Changes in skin texture—thin or shiny.
- Changes in nail and hair growth.
- Abnormal sweating.
- Rough and excess bone growth.
In some cases, these signs and symptoms disappear on their own, and in others, they may continue for months, even years. The first signs of CRPS are pain, inflammation, redness, sensitivity and temperature changes. As the syndrome progresses, the affected area can get pale and cold. Skin, hair, and nail changes can occur, as well as muscle tremors or spasms. Once CRPS reaches this point, the syndrome is irreversible.
Symptoms of CRPS Compared to Symptoms of Peripheral Neuropathy
When looking at the affected body parts and symptoms of CRPS, it appears very similar to another illness called peripheral neuropathy, which also affects the hands and feet and occurs as a result of nerve damage. While they do share some symptoms, like muscle weakness, burning sensation and sensitivity to touch, there are a few notable differences.
Someone with peripheral neuropathy might also experience:
- Numbness, tingling or prickling in the hands and feet.
- Bladder, bowel or digestive problems.
- Sudden drops in blood pressure, resulting in light head nests or dizziness.
- Lack of coordination.
- Falling.
- Paralysis, if the nerves affected are motor nerves.
- Sensation of wearing socks or gloves when not.
Symptoms those with peripheral neuropathy would not be sharing with CRPS:
- Changes in color and texture of the skin.
- Spasms or tremors.
- Inflammation.
- Changes and nail and hair growth.
The pain and sensitivity levels tend to be more extreme with those suffering from CRPS. They can also present with unique symptoms not seen with peripheral neuropathy, like sleep disturbance or depression. Additionally, untreated CRPS can spread to other parts of the body. This is not a progression seen in peripheral neuropathy.
Causes of Complex Regional Pain Syndrome
While the causes of CRPS are still being evaluated, it is surmised that the cause is injury or change in the peripheral and central nervous systems. The peripheral C-fiber nerve fibers responsible for sending pain messages to the brain misfire. This improper function triggers inflammation that would typically signal healing and the need for rest of the affected area.
CRPS manifests in two ways or types. While they may share some similar symptoms, the causes differ:
- Type 1—Reflex sympathetic dystrophy (RSD) is triggered by an injury or illness that did not cause nerve damage in the affected area. Type 1 is the most common, accounting for 90% of the people affected by CRPS.
- Type 2—Once known as causalgia, this type is triggered by definite nerve damage.
While many cases of CRPS are diagnosed after some impactful trauma to the leg or arm, other types of trauma like surgery, infections, sprains, heart attacks, and stroke can also lead to the syndrome. It is important to note, not all injuries or illnesses will develop into CRPS.
One of the biggest differences between CRPS and peripheral neuropathy are the causes. When treating an individual with CRPS, the syndrome is typically a result of a fracture, sprain or surgical procedure. However, one of the leading causes of peripheral neuropathy is diabetes.
Complications of Complex Regional Pain Syndrome
If a diagnosis of CRPS isn’t made early enough to get proper treatment, the syndrome could progress to more debilitating symptoms.
- Tissue atrophy—tissue wasting is when the bones, skin, and muscles weaken and deteriorate if you cannot keep the affected area active due to pain or stiffness.
- Muscle contracture—muscles will experience tightening, which could lead to the arm/hand or feet/toes permanently contracting into a fixed position.
Prevention of Complex Regional Pain Syndrome
There are two keys ways in which you can lessen the risk of developing CRPS:
- Take vitamin C after a wrist injury. Studies show that high doses of vitamin C after fracturing the wrist may lower the potential of developing CRPS compared to subjects who did not take doses of vitamin C.
- Physical therapy after a stroke. Research studies propose that individuals who become mobile soon after experiencing a stroke reduce their potential to develop CRPS.
Diagnosis of Complex Regional Pain Syndrome
No specific test is designed to diagnose CRPS or identify the exact nerve that may be injured. Diagnosis can include any of the following:
- In-depth examination by a neurologist, plastic surgeon or orthopedist with knowledge of standard patterns of sensory nerve anatomy.
- Magnetic resonance imaging (MRI) or ultrasound can expose nerve damage. In particular, MRIs can help identify damaged nerves in bone marrow or bone abnormalities.
- Triple-phase bone scans can, at times, show CRPS-related excess bone resorption using a dye.
- Nerve conduction studies have been proven to identify most CRPS-related nerve trauma. This method cannot identify some injuries because the affected nerve branches are too small.
Treatment for Complex Regional Pain Syndrome
Some cases, especially those diagnosed early or are mild, recover with early intervention. Common treatments include:
- Physical therapy and rehabilitation
- Graded motor imagery
- Spinal cord stimulation
- Spinal-fluid drug pumps
- Medications
- Surgical sympathectomy
- Sympathetic nerve block
- Psychotherapy
- Cutting injured nerve roots and nerves
- Amputation
Final Thoughts
The key to CRPS is early detection. With early diagnosis and treatment, the affected area can fully recover. Contact your physician or healthcare provider immediately if you’re experiencing any signs or symptoms of CRPS.
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Sources
- “Complex regional pain syndrome – Symptoms and causes – Mayo Clinic”. Mayo Clinic
- “Complex Regional Pain Syndrome Fact Sheet | National Institute of Neurological Disorders and Stroke”. National Institute of Neurological Disorders and Stroke
- “Complex regional pain syndrome – Diagnosis – NHS”. NHS
- “Peripheral neuropathy – Symptoms and causes”. Mayo Clinic
- “What is the Difference between Peripheral Neuropathy and Complex Regional Pain Syndrome?”. RSDSA
