CRPS – complex regional pain syndrome
What is complex regional pain syndrome?
Complex regional pain syndrome is a chronic condition which causes pain in the arms, hands, legs, and feet. It affects the hand most. This condition is also known as the shoulder-hand syndrome or causalgia, reflex sympathetic dystrophy, Sudeck’s atrophy. Its exact cause is not clear. It commonly develops after an injury, surgery, pressure on a nerve, neck diseases, infection, cancer, heart attack or stroke. In some cases CRPS occurs without any reason. CRPS presents as prolonged or excessive pain (for months) and changes in skin color, temperature, and/or swelling in the affected area.
It is of two types depending upon its causes-
- It develops after an injury or illness that does not involve nerves of the affected area. This type is also termed as reflex sympathetic dystrophy syndrome (RSD). Most patients of complex regional pain syndrome (90%) develop type 1.
- It develops after a distinct nerve injury. It is also termed as causalgia. It represents symptoms similar to Type 1.
Complex regional pain syndrome can develop in any person at any age. It is more common in women in the age of 20- 40 years with the peak incidence at the age of 40 years. It rarely occurs in old people or children below the age of 10 years. It is not seen in children below the age of 5 years. It has been reported that the incidence of CRPS is 0.8 per 100000 persons with a prevalence of 21 people per 100000 in Type 1 and 4 people per 100000 for type 2 CRPS. 12% of brain injury, 1-5% of peripheral nerve injury and 5 % of myocardial infarction can cause CRPS. 1% of injuries or surgeries can cause CRPS.
What are the symptoms of complex regional pain syndrome?
Complex regional pain syndrome represents symptoms in following stages according to onset and duration-
- Stage 1- acute stage-
It may remain for 3 months. You may feel high sensitivity to touch and burning pain as the initial symptoms. Pain is persistent and long lasting in the affected extremity followed by swelling and stiffness. Warmth and redness are also felt. You may also observe the faster growth of nails and hair with high perspiration.
- Stage 2- dystrophic stage
This stage may end in 3-12 months. swelling becomes more prominent and wrinkles in the skin disappear. The skin becomes cold and nails become brittle. Pain spreads everywhere, stiffness and sensitivity to touch are more increased.
- Stage 3- Atrophic stage
It happens after one year. The dryness and paleness occur in the skin. it can be tightly stretched and shiny. stiffness increases so much that you cannot move your affected part. Pain may reduce and the condition appears in other areas of the body.
The symptoms could vary during the course of the day and patients are usually anxious or depressed and have anegative outlook towards the affected limb.
How is it diagnosed?
Your orthopaedic surgeon will inquire you of your symptoms and medical history. He will examine your affected limb. The person suffering from CRPS is very protective of his affected part as slightest of touch can trigger severe pain. Diagnosis is made clinically using Budapest Criteria. However x-rays, MRI scan and bone scan could be beneficial in some cases.
What happens if nothing is done?
CRPS is poorly understood and the outcome is variable. It may lead to chronic pain and disability of the affected part resulting in a daily struggle to move the involved part for years. Chronic CRPS lead to tissue wasting i.e atrophy of skin, bone and muscle often resulting from muscle contracture. It can be treated with best results if diagnosed early. The earlier it is treated, better is the prognosis.
How is it treated?
The main goal of treatment of CRPS is to increase the movement of the affected extremity and relieve the pain. Early diagnosis and early treatment are effective in case of CRPS. With passing time, the disease becomes complex to treat. Conservative treatment is the main stay treatment of this condition and includes physical therapy, psychotherapy, hand therapy, pain mangement with pain clinic referral, medicines, heat and cold therapy.
What are the non-operative treatments?
The non-operative treatment involves the following-
- Physical therapy and Hand therapy- a set of gentle, guided exercise program is recommended to improve the blood flow into the affected extremity and control the circulatory symptoms. Exercises enhance the flexibility, function, range of motion and strength of the affected part. It assists a lot in the relief of pain and other symptoms.
- Occupational therapy – desensitisation, stress management and body perception awareness techniques.
- Psychotherapy- CRPS patients have a tendency to develop anxiety, depression or post-traumatic stress disorder. It increases the perception of pain and makes the rehabilitation program more difficult. Psychotherapy may help them to recover fast.
- Pain mangement –This is usually offered by pain specialists. Different classes of medicines are effective in the treatment of CRPS. They are more effective when used in the early stages of the disease. The medicines that are used to treat CRPS are-
- Non-steroidal anti-inflammatory medicines such as aspirin, ibuprofen, etc to control pain and inflammation.
- Opioids such as morphine used as painkillers
- Corticosteroids like prednisolone usually used in early stages to control swelling and inflammatory changes in the affected area
- Biophosphates such as calcitonin and alendronate used to prevent bone loss
- Antipsychotic medicines such as amitriptyline, gabapentin, nortriptyline, etc are used to treat seizures or depression.
- Ketamine is given intravenously in order to manage pain.
- Anaesthesia is given near the sympathetic nerves to relieve the pain. It is usually recommended in the early stages of CRPS to control its progression to later stages.
These drugs are prescribed either singly or in combination to treat CRPS. They may cause side effects like impaired memory, elevated heartbeat, dizziness and drowsiness.
- Heat therapy- application of heat on the affected part can relieve swelling and discomfort on the affected part.
- Biofeedback– biofeedback techniques increase awareness and relaxation that relieve pain to a great extent.
In retractable cases the following interventions could be considered to manage pain and disability caused due to CRPS.
- Surgical sympathectomy- the use of this surgery is controversial. In this technique, some of the nerves are blocked to relieve pain in the patient. Surgeons apply this technique only in patients of CRPS who responded well by sympathetic nerve blocks.
- Spinal cord stimulation- in this procedure, electrodes are implanted into the spine near the spinal cord through a needle. These electrodes transmit tingling sensation in the form of small electric current in the painful part. They are implanted temporarily until it is helpful.
- Intrathecal drug pumps- a small device is implanted near the abdomen which discharges pain medicines directly into the spinal cord.
When can I return to driving and work?
Usually, most patients with CRPS type 1 (80%) have a complete restoration of symptoms and mobility in 18 months. In the authors experience, most patients with CRPS are able to continue their jobs with some work place alterations. Recovery depends on the type of CRPS, severity of symptoms, secondary disability developed, age and job of the patient. Your surgeon can give you better advice on this.
45 year old gentleman developed CRPS (left hand) following conservative mangement of knuckle fracture (5th metacarpal). The left hand is swollen, erethematous, painful, increased sweating and reduced function. It took almost 1-2 years for the patient to regain the function back in his hand.