Treatment Options for RSD
Although the success of treatment of reflex sympathetic dystrophy (RSD) varies from patient to patient and is related to the duration and severity of symptoms, there is general agreement that early diagnosed RSD responds better to treatment than established or long-standing RSD. It is, therefore, important to start treatment as soon as possible after the diagnosis of reflex sympathetic dystrophy has been established.
In general, the following treatment options may be considered for the management of patients with RSD:
- Physical therapy
- Drug therapy
- Sympathetic nerve blocks
- Nerve stimulators
Physical therapy is considered an important, first-line treatment for RSD and may be used alone or in combination with other treatments such as nerve blocks and drug therapy. The primary goals of physical therapy include:
- Restore function of the limb
- Alleviate pain
- Strengthen muscles
- Reduce swelling and joint stiffness
The steps to achieve these goals include:
Raising the awareness of and educating the patient regarding the need to use the limb despite the pain. The patient participates in the process by working with the rehabilitation counselor or physical therapist to set goals and a timetable of increasing demand and intensity.
Raising the tolerance level for touch and desensitizing the affected area by providing sensory stimulation of increasing intensity and duration. The patient's participation in increasing types of stimulation, intensity and duration is important since it may provide the motivation for success of treatment.
Increasing functional use of the limb through:
- increasing flexibility with increased range of motion exercises
- increasing muscle strength with isometric exercises
- improving posture and balance (for lower extremity RSD)
- movement training (e.g., walking) if RSD is severe
Motion exercises are important for the whole limb, not just for the joint that is affected since the movement increases blood circulation around the joints which provides nutrition for the cartilage and decreases the hypersensitivity of the area. This prevents or minimizes contracture of the limb.
A variety of physical therapy methods may be used including:
- Whirlpool therapy
- Massage therapy
- Hot/cold compresses
- Range of motion exercises
- Limb elevation
While undergoing physical therapy, some patients benefit from drug therapy and psychotherapy so that the pain of physical therapy does not discourage them from fully cooperating and carrying out the treatment plan. Current data has shown benefit from physical therapy for the short-term but long-term benefit is as yet undetermined.
Vocational rehabilitation may also be used in order to help the patient develop new skills or employ already exiting skills to occupy themselves in a positive way and increase their self-esteem and quality of life. This step is important since relapse seems to be more likely when a person is inactive. This step is also important as it impacts on the patient's social life with friends and family.
Prompt initiation of medications is very important, especially if the pain is intense. During the course of treatment, medication doses may have to be adjusted to achieve optimal pain relief. There are various classes of drugs that may be used for the treatment of RSD including:
Analgesics (Pain Medications)
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Narcotic analgesics - usually reserved for severe, chronic pain that does not respond to other pain medications
A variety of anticonvulsants have been used in RSD patients to provide pain relief including:
- Phenytoin (Dilantin)
- Gabapentin (Neurontin)
- Carbamazepine (Tegretol)
Muscle relaxants are used to control and provide relief from muscle cramps and muscle spasms that may be associated with RSD. Examples of muscle relaxants include:
- Clonazepam (Klonopin)
- Baclofen (Lioresal)
Examples of antidepressants that may be used in the treatment of RSD include:
- Amitriptyline (Elavil)
- Doxepin (Sinequan, Adapin)
- Nortriptyline (Pamelor, Aventyl)
This class of drugs is used to reduce inflammation and swelling. Corticosteroids, such as prednisone and methylprednisolone, have demonstrated good analgesic efficacy in controlled clinical trials in patients with early-stage RSD. Patients must be monitored carefully for potentially serious side effects while on corticosteroids including susceptibility to infections and avascular necrosis of bone.
This class of drugs may help relieve severe cases of RSD with widespread pain.
Intranasal calcitonin spray (200 IU per day, administered in both nostrils, has been demonstrated to be an affective treatment for RSD pain.
Intrathecal Drug Delivery
The term "intrathecal drug delivery" refers to the administration of drugs into the spinal fluid through the intrathecal space (the space surrounding the spinal cord). Medications can be delivered within the intrathecal space by either injection through a needle or via a catheter that is connected to a pump. Drugs that may be used to control chronic pain by intrathecal drug delivery include morphine and baclofen. Long-term experience with the morphine pump in patients with chronic pain, including those with RSD, indicates few advantages over oral morphine administration. In fact, many patients with implantable morphine pumps also require oral morphine supplementation to control their pain. The implantation of a morphine pump is also associated with potential complications including:
- Spinal fluid leaks
- Injury to the spinal cord
- Malfunction of the pump
Sympathetic Nerve Blocks
A sympathetic nerve block is a procedure usually performed by a pain management specialist (anesthesiologist) that involves injecting a pain-relieving drug into an area of sympathetic nerve endings (ganglion) to interrupt or block sympathetically-maintained pain. Additional nerve blocks are usually repeated at 7 to 10 day intervals and continued until the pain diminishes. If the pain is determined to be sympathetically-maintained pain, then sympathetic nerve blocks usually provide immediate, although temporary, pain relief and also increase the patient's level of comfort and function. Recurrence of pain after the initial nerve block occurs in many patients requiring subsequent sympathetic nerve blocks or stronger measures. Despite popular opinion, there is little evidence-based information regarding the best timing for administering nerve blocks, the number that should be administered, or its long-term efficacy. Some clinicians suggest their administration only in order to reduce pain while facilitating physical therapy and rehabilitation.
There are several types of nerve blocks that may be administered including intravenous regional nerve blocks (IVRB), stellate (cervical) ganglion sympathetic blocks, or lumbar sympathetic blocks. Drugs that may be used for nerve blocks to relieve pain include:
- Local anesthetics (lidocaine, bupivacaine)
- Guanethidine monosulfate (Esimil; Ismelin)
- Bretylium tosylate (Bretylol)
- Phentolamine mesylate (Regitine)
Advantages of sympathetic nerve blocks include:
- Short to long-term pain relief depending upon the severity of the RSD
- Does not block motor activity so the patient can remain mobile and active after nerve block administration
- Offers an opportunity for the patient to perform physical activity such as range of motion exercises during the time interval when the nerve block has diminished the degree of pain
Potential complications that may result from sympathetic nerve blocks include:
- Nerve injury
- Bleeding - nerve blocks are usually contraindicated in patients who are taking anticoagulant medications
- Allergic reactions - nerve blocks with local anesthetics are contraindicated in patients who are allergic to these medications
- Psychological reactions - anxiety and fear related to apprehension about the nerve block procedure
Because a variety of complications can occur as an undesired side-effect of sympathetic nerve blocks, it is prudent for patients to select a pain management specialist, such as an anesthesiologist, who is experienced with this technique.
Sympathectomy is a procedure that is intended to destroy the collection of sympathetic nerve cells (sympathetic ganglion) in a specific area along the spinal cord. Because a sympathectomy is a procedure that caries certain risks and the outcome may vary from patient to patient, it is usually considered as a last resort treatment option for the management of RSD. Patients offered a sympathectomy as a treatment for reflex sympathetic dystrophy should carefully weigh the risks and benefits before undergoing this procedure.
Patients are considered as potential candidates for sympathectomy only if it has been determined that the source of the RSD pain is sympathetically-maintained pain that is reduced with a sympathetic nerve block. If the source of the RSD pain is determined to be sympathetically-independent pain (i.e., no reduction of pain is noted after a nerve block), a sympathectomy is not a viable treatment option.
There are 2 types of sympathectomy:
- Chemical sympathectomy
- Surgical sympathectomy
During a chemical sympathectomy, a neurolytic agent (a chemical that destroys nerve cells) is injected into the sympathetic ganglion at a specific site to block sympathetically-maintained pain. Phenol and ethanol are the two most frequently used neurolytic agents for chemical sympathectomy.
Potential complications of chemical sympathectomy include:
- Post-sympathetic pain
- Neuritis - inflammation of a nerve due to irritation from the phenol or ethanol
A surgical sympathectomy is a procedure that involves surgically cutting and cauterizing (sealing) the nerves of the sympathetic ganglion at a specific location along the spinal cord. The goal of this procedure is to suppress or block the sympathetically-maintained pain in the affected area. There are various techniques that may be used to perform a surgical sympathectomy, including video-assisted surgery, open surgery, or radiofrequency sympathectomy.
Following a surgical sympathectomy, the patient may experience complete pain relief, partial pain relief, or no pain relief. In general, many patients experience complete or partial pain relief for several months following a surgical sympathectomy but only about 15% to 30% experience long-term relief lasting two years or longer.
In a study published in 2002 in the Journal of Vascular Surgery, researchers from the University of South Florida College of Medicine reported that 10% of the patients with RSD who underwent surgical sympathectomy were considered treatment failures, while the remainder reported at least 50% reduction in pain intensity. There was a long term benefit noted from the procedure, although the level of pain reduction deteriorated over time.
Potential complications of surgical sympathectomy include:
- Post-sympathectomy pain - pain associated with the surgical procedure which has been reported to occur in about 40% of patients
- Compensatory hyperhidrosis - excessive sweating of the face, trunk, or legs
- Recurrence of RSD pain
- Pneumothorax - accidental injury to the lung
- Horner's syndrome - a syndrome caused by injury to the sympathetic nerves of the face which includes a constricted pupil, drooping eyelids, and facial dryness
- Reduced blood pressure when standing (postural hypotension)
Patients who are offered a surgical sympathectomy as a treatment option for their RSD pain should carefully find out about the surgeon's experience and success rate with this procedure before undergoing the procedure.
Another treatment option for patients with RSD is the use of electrical nerve stimulators that apply a small amount of electrical current to the nerves to overcome the sensation of pain. This type of treatment is known as electrostimulation or neuromodulation. The two most commonly employed neurostimulation techniques are transcutaneous electrical nerve stimulation and spinal cord stimulation.
Transcutaneous Electrical Nerve Stimulation
Transcutaneous electrical nerve stimulation, also known as TENS, is a noninvasive treatment that sends an electrical current to specific nerves to relieve pain, reduce stiffness, and improve mobility. A typical TENS unit consists of an electrical signal generator, a battery, and a set of electrodes. The electrode patches are placed on the skin at the area to be treated and a mild current is generated from the stimulator that runs through the electrodes to the area of pain. Portable TENS units are available for self-treatment with a small battery-operated stimulator that can be worn around the waist. The patient can turn the stimulator on or off as needed for pain control. It is important for a health care provider, such as a physical therapist, to carefully instruct the patient on the proper use and care of the TENS unit especially the correct placement of the electrodes. Complications of TENS units are rare with skin irritation at the site of electrode placement being the most common side-effect.
Contraindications to the use of a TENS unit include:
- Patients with an implanted pacemaker
- Women who are pregnant - risk of premature labor
- Areas of sensory impairment - the electrodes should not be placed in an area with sensory nerve impairment (e.g., neuropathy) because of the risk of burns to the area.
Spinal Cord Stimulators
A spinal cord stimulator (SCS) is a device that consists of a power source, leads (wires), and an external controller. A small wire, called a lead, is surgically implanted into the epidural space of the spinal column and is connected to a power source and an external unit controlled by the patient. When the patient initiates the flow of electrical current from the external unit, low-level electrical impulses are transmitted through the lead wire to the spinal cord to interrupt and block pain that is perceived by the brain. SCS affects the entire central nervous system. Peripheral nerve stimulators (PNS) are similar to spinal cord stimulators with the difference being that the electrodes are placed outside the central nervous system and they target the peripheral nervous system.
In most cases, before a SCS is implanted permanently, a temporary stimulator is implanted for a trial period of several days to determine if the patient will experience a reduction in the level of pain. If good pain control is achieved during the trial period, the next step is the surgical implantation of a permanent SCS. Patients with implanted SCS often describe the sensation of the electrical current from the SCS as a "tingling" feeling, however, these sensations are far less bothersome compared to the pain associated with RSD.
Potential risks and complications associated with surgical implantation of SCS include:
- Spinal cord injury
- Failure to relieve pain
- Pain at the site of the implant
- Hardware malfunction
Spinal cord stimulators enable patients suffering from chronic pain a means of better controlling their pain. Patients are usually able to resume their normal activities both at home and at work and also participate in recreational activities. Although SCS is not a cure for chronic pain, in many cases it can reduce the level of intensity of the pain and make it more manageable.
Contraindications to the use of SCS include:
- Patients with implantable devices such as a pacemaker or defibrillator
- Patients undergoing radiation therapy
- People who are exposed to detection equipment devices including anti-theft devises, security devices, and aircraft communication systems
Though some patients report successful control of pain in studies involving SCS compared to placebo groups, there is currently no absolute proof of efficacy. When spinal cord stimulation is combined with physiotherapy, there is evidence of greater pain relief than with physical therapy alone. There is some indication that SCS may be effective in patients who have already undergone surgical sympathectomy. Spinal cord stimulation seems to produce analgesia without any reduction of sympathetic function.