Complex regional pain syndrome (CRPS) is a condition of intense burning pain, stiffness, swelling, and discoloration that most often affects the hand. Arms, legs, and feet can also be affected by CRPS. It is caused by damage to, or malfunction of, the peripheral and central nervous systems.
The central nervous system is composed of the brain and spinal cord, and the peripheral nervous system involves nerve signaling from the brain and spinal cord to the rest of the body. CRPS is characterized by prolonged or excessive pain and mild or dramatic changes in skin color, temperature, and/or swelling in the affected area.
CRPS symptoms vary in severity and duration. Studies of the incidence and prevalence of the disease show that most cases are mild and individuals recover gradually with time. In more severe cases, individuals may not recover and may have long-term disability.
Types of CRPS
There are two types of CRPS –
- CRPS Type 1 – Used to be known as reflex sympathetic dystrophy, Sudeck’s atrophy, reflex neurovascular dystrophy, or algoneurodystrophy. No damage has occurred. It is triggered by an apparent trivial injury, such as a fractured or sprained ankle.
- CRPS Type 2 – Used to be known as causalgia. This is triggered by a more serious injury, such as a broken bone or some surgical operation. It may also be caused by a serious infection. In all cases there is clear evidence that nerve damage has occurred.
Anyone can get CRPS. It can strike at any age and affects both men and women, although it is much more common in women. The average age of affected individuals is about age 40. CRPS is rare in the elderly. Children do not get it before age 5 and only very rarely before age 10, but it is not uncommon in teenagers.
Causes
The exact cause of CRPS is unknown but may result from irritated and damaged nerves of the sympathetic nervous system. Even relatively minor trauma to a body part may lead to CRPS.
The sympathetic nervous system is a division of the autonomic nervous system (ANS) which controls unconscious bodily functions including digestion, regular beating of the heart, blood flow, sweating and salivation. In CRPS dysfunctional sympathetic nerves are thought to send inappropriate messages to the brain. These interfere with normal messages regarding sensation, temperature and blood flow.
A number of different events can trigger the condition. These include –
- Trauma (injury)
- Surgery
- Some forms of arthritis
- Heart disease
- Stroke
- Nerve entrapment conditions
- Shingles
- Shoulder problems
- Breast cancer
CRPS also occurs in some people with fibromyalgia. A common nerve entrapment condition that can trigger CRPS is carpal tunnel syndrome. In approximately one third of all cases, no trigger can be identified.
Symptoms
CRPS can affect the nerves, skin, muscles, blood vessels and bones simultaneously. Symptoms can be gradual or rapid in onset and can vary in severity. They normally occur in three stages: acute, dystrophic and atrophic. Signs and symptoms occurring in these three stages may include –
- Stage 1 of CRPS – Typically lasts from 1 to 3 months. There is a severe, burning pain in one of the limbs. There may be muscle spasms (involuntary muscle contractions), joint stiffness and fast-growing hair and nails. Skin color and temperature may also change as blood vessels in the area are affected.
- Burning pain
- Swelling of an extremity
- Vasospasm (constriction of blood vessels) affecting skin colour and temperature.
- Excessive sweating
- Tenderness.
- Stage 2 of CRPS – Usually lasts for 3 to 6 months. Pain in the affected limb, hand or foot may get worse, as may alterations in skin texture and color. Muscle tone may weaken. Inflammation and stiffness may worsen.
- Intensified pain
- Shiny skin
- Thickened skin
- Contracture development (tightening and shortening of muscles)
- Diminished swelling.
- Stage 3 of CRPS – Changes that have occurred so far are usually irreversible at this stage. There will be significant loss of muscle tone in the affected limb, bones may have become contorted, while the joints have become stiffer. The patient will likely find it very hard to use the affected limb. Patients who receive prompt treatment for CRPS early on are very unlikely to ever reach this stage.
- Skin changes become irreversible
- Significant osteoporosis can be shown on x-ray
- Thinning of the fatty layers under the skin
- Restricted movement due to contractures
- Pain unyielding and may have spread to other areas of body
Other possible signs and symptoms include –
- Changes in skin temperature – the skin may be sweaty on some occasions, and cold and clammy in others.
- Changes in skin color – there may be blotches or streaks on the skin. It may range in color from very pale to pink. Sometimes the affected area of skin may take on a blue tinge.
- Skin texture – the skin may sometimes seem thin and shiny.
- Nails and hair – hair and nails may grow at unusual speeds (too slow or too fast).
- Joints – the affected joint(s) may be painful, stiff and inflamed.
- Mobility – the patient may find it harder to move the affected limb or part of limb.
Complications
- Muscle atrophy (muscle withers) – if a limb is not used for any reason, which in this case would be pain, the muscles begin to waste.
- Contracture – the hand, fingers or foot, depending on which area is affected, may contract into a fixed position as the muscles gradually tighten.
- CRPS may spread – CRPS symptoms may spread to the opposite limb, hand or foot (mirror-image type), to a distant part of the body (independent type), or to a nearby site (continuity type).
Treatment
Medications – Doctors often try medication first. Because each person responds differently to medication, your doctor may try a variety of doses and drugs. Medications range from over-the-counter pain relievers, such as aspirin, acetaminophen and anti-inflammatory steroids to stronger pain medicines. These may include –
- NDSAIDs (nonsteroidal anti-inflammatory drugs) – OTC (over-the-counter, no prescription required) NSAIDs such as ibuprofen, naproxen sodium or aspirin may relieve pain and inflammation.
- Antidepressants – such as amitriptyline may be prescribed for neuropathic pain (pain caused by a damaged nerve). Should not be taken by those with a history of heart disease. Side effects may include drowsiness, dry mouth, blurred vision, constipation and problems urinating. Individuals who feel drowsy should not drive or operate heavy machinery.
- Anticonvulsants – these were originally designed for epilepsy treatment. As side effects may include loss of coordination, drowsiness, dizziness and fatigue, patients may have to refrain from driving or operating heavy machinery.
- Corticosteroids – such as prednisone may reduce inflammation.
- Bone-loss medications – such as alendronate (Fosamax) and calcitonin (Miacalcin) may also be prescribed.
- Opioid medications (opiates) – Opioids (opiates) are a class of drugs that are commonly prescribed for their analgesic or pain-killing, properties.
- Sympathetic nerve-blocking drugs – an anesthetic may be injected, blocking the nerve fibers in the affected nerves.
- Topical analgesics – topical means “applied onto the skin”. Several types of creams, such a lidocaine, or a combination of ketamine, clonidine and amitriptyline may reduce hypersensitivity.
Surgical Treatment – If nonsurgical treatment fails, there are surgical procedures that may help reduce symptoms.
- Spinal cord stimulator – Tiny electrodes are implanted along your spine and deliver mild electric impulses to the affected nerves.
- Pain pump implantation – A small device that delivers pain medication to the spinal cord is implanted near the abdomen.
Physiotherapy attempts to build or recondition muscles – allowing the person to move more normally and with less pain. The doctor may recommend passive physical therapy, such as massage and applying heat/cold, or active therapies, such as exercise.
Medical Devices – Medical devices, such as neurostimulators or drug pumps (intrathecal drug delivery systems), are surgically placed devices that modulate pain signals before they reach the brain.
Alternative Treatment
Nutritional supplements – Vitamins, minerals, and added antioxidants may be recommended by a nutritional specialist. These supplements are thought to improve and strengthen the immune system, which may in turn have a positive influence on CRPS symptoms.
Omega-3 Fatty Acids – Fatty acids are essential nutrients derived from dietary intake of fats. They are an important source of energy for the body, and serve a variety of other biologic functions. Conversely, excessive levels of omega-6 PUFAs, such as arachidonic acid, are associated with inflammatory activities, an effect that can be offset by the simultaneous consumption of omega-3 PUFAs.
Gamma linolenic acid (GLA) is a plant-derived omega-6 most abundant in seeds of an Eastern flower known as borage. GLA plays an important role in modulating inflammation throughout the body, especially when incorporated into the membranes of immune system cells.
B Vitamins – Vitamins B1 (thiamine), B6 (pyridoxine), and B12 (cyanocobalamin/ methylcobalamin) are not only beneficial for managing pain that may result from a vitamin B deficiency, but are also effective (alone or in combination) with other conventional medications for various painful diseases.
Vitamin C – Vitamin C (ascorbic acid), a versatile antioxidant, may act as another natural shield against pain. Accumulating evidence indicates that free radicals play a role in the exaggeration of pain hypersensitivity.
Vitamin D – Vitamin D is a prohormone version of an important hormone called 1,25-dihydroxycholecalciferol or 1,25-dihydroxy vitamin D, also known as calcitriol (Dusso 2005). Vitamin D, once converted into calcitriol, inhibits inflammation by regulating some of the genes responsible for producing pro-inflammatory mediators.
Proanthocyanidins – Proanthocyanidins (tannins) belong to a group of chemical compounds called “flavonoids”, which provide a variety of beneficial functions for humans (e.g., their well-known antioxidant and anti-inflammatory affect). Grape seed is an especially rich source of proanthocyanidins, which have been associated with symptom reduction in a variety of painful diseases.
Melatonin is a naturally occurring hormone that is synthesized by the pineal gland and regulated by the environmental light/dark cycle. Melatonin can reduce pain through its beneficial effect on sleep, as well as its analgesic properties. It is also a potent antioxidant, and has been shown to reduce the pain associated with a variety of chronically painful conditions.
Methylsulfonylmethane – Methylsulfonylmethane (MSM) is an organic sulfur-containing compound. Among its many beneficial functions, MSM has been shown to display anti-inflammatory and antioxidant properties and pain management.
Acupuncture or acupressure – These treatments utilize thin needles to relieve pressure points in the affected area.
Reference –
http://painhealth.csse.uwa.edu.au/pain-condition-complex-regional-pain-syndrome.html
https://www.rcplondon.ac.uk/guidelines-policy/pain-complex-regional-pain-syndrome
http://www.cincinnatichildrens.org/health/c/rsd/
http://www.bodyinmind.org/what-is-complex-regional-pain-syndrome-in-plain-english/
http://rsds.org/wp-content/uploads/2015/02/deMosM_SturkenboomMCJM_HuygenFJPM.pdf\
http://familydoctor.org/familydoctor/en/diseases-conditions/complex-regional-pain-syndrome.html
http://orthoinfo.aaos.org/topic.cfm?topic=a00021