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Reflex Sympathetic Dystrophy Syndrome

What is Reflex Sympathetic Dystrophy Syndrome?

Reflex Sympathetic Dystrophy Syndrome (RSDS) is a somewhat hard-to-pin-down chronic nerve disorder associated with injured soft tissue (such as a nerve) that doesn’t heal right. More commonly known today as Complex Regional Pain Syndrome (CRPS), RSDS usually affects the extremities but symptoms can show up just about anywhere in the body. The pain and difficulties that arise due to RSDS may or may not be in proportion to the magnitude of the injury. Then again, RSDS can develop without a “precipitating event.”

Doctors used to describe RSDS as progressing in stages. But the course of the disease seems to be rather unpredictable and many symptoms appear and disappear at different times, so the stages model is no longer seen as accurate. RSDS often progresses at different speeds in different patients. It is believed to occur after 1-2% of all bone fractures and 2-5% of all nerve injuries. Minor injuries, such as an ankle sprain or a fall, have been shown to bring on RSDS. Because this ailment affects different patients in different ways, a variety of treatments are used with some success.

The Mechanics of Reflex Sympathetic Dystrophy Syndrome

The mechanism that triggers RSDS remains unclear. For reasons that are not well understood, a “sympathetic” nervous system seems to produce an extensive range of distress-causing symptoms rather than shut down aspects of the nervous system. The condition tends to be progressive if not easily predictable. It usually runs from the injury up the affected extremity and then spreads on the same side of the body or to the opposite extremity. If diagnosed early, RSDS can be cured or at least mitigated. Left untreated, it can lead to permanent deformities in the areas affected, chronic pain, and psychological problems.

Symptoms of Reflex Sympathetic Dystrophy Syndrome>

Symptoms indicating RSDS / CRPS are generally progressive and can include:

  • pain out of proportion to the injury
  • dramatic loss of mobility at injury site
  • burning sensation
  • various pathological changes in the bone and skin
  • excessive sweating
  • localized swelling
  • extreme sensitivity to touch

All of these symptoms can spread and become more intense as time passes. The pain can become unbearable, requiring medication. Hair and nails might begin to change. Muscle and even bone can begin to deteriorate and atrophy.

Causes of Reflex Sympathetic Dystrophy Syndrome

The most common and recognized cause of RSDS is injury or trauma. But “precipitating factors” associated with RSDS can include:

  • certain heart diseases, including myocardial infarction
  • cervical spine or spinal cord disorders
  • lesions on the brain
  • certain infections
  • invasive surgery
  • repetitive motion disorders leading to such ailments as carpal tunnel syndrome

In some patients, however, a definite e cause or “precipitating event” cannot be identified despite the presence of symptoms.

Diagnosing Reflex Sympathetic Dystrophy Syndrome

There are two types of RSDS / CRPS: Type I cases lack an identifiable “precipitating event,” while Type II cases are tied to a definite and distinct nerve injury. There is no single or definitive test to diagnose either type of RSDS / CRPS, so doctors assess both the patient’s medical history and the findings of a medical exam. The exam also must rule out other disorders with clinical features similar to RSDS / CRPS, such as blood clots or a spreading cancer tumor that can cause pain and swelling in an extremity.

Generally, a diagnosis of RSDS / CRPS is made when the doctor can establish the following:

  • A trauma or injury in the recent past
  • Pain that is disproportionate to the “precipitating event”
  • Such characteristic symptoms as swelling, hindered movement, changes in tissue growth, and abnormal function of the sympathetic nervous system

Not all of these symptoms might be present, however, and there might be others. The primary characteristic of the diagnostic process resembles that of a detective piecing together evidence to prove RSDS / CRPS beyond a reasonable doubt.

Treating RSDS

Because of the broad and somewhat ambiguous nature of the ailment, there are a wide range of recommended treatments that have been shown to mitigate symptoms and bring relief. But the goal of any treatment regimen is normal use of the affected part of the body as much as possible. To that end, treatment usually concentrates on mobility and pain management strategies. The most common and proven treatments include:

  • Nerve blocks, usually performed by a pain specialist, can range from temporarily numbing a nerve with anesthetics to destroying a nerve surgically (sympathectomy). A nerve block can provide a cure or it can produce further diagnostic information to help understand the scope and location of the ailment.

  • Properly applied, physical therapycan contribute greatly to regaining normal physical function. The patient is shown how to use the affected body part in daily living and engages in non-load bearing exercises (in a pool, for example) to help stay limber and in balance. There have been instances in which physical therapy has been misused or overused, however, so a clear understanding of RSDS is needed by the therapist.

  • Various pain medicationscan be prescribed to address such conditions as chronic pain, sleeplessness, injury-related pain, spontaneous or jabbing (lancinating) pain, “sympathetic” pain, or muscle cramps. In all cases, side effects must be taken into account and use must be monitored closely by a doctor.

  • Counseling and related psychosocial techniquescan help a patient cope with the pain and other symptoms. Usually, pain is a defense mechanism that warns us when something is wrong and prompts a change in behavior. But with RSDS / CRPS, the “sympathetic” nervous system acts abnormally. The pain has no positive, protective purpose. Learning that “to hurt is not to harm” is difficult, but it can go a long way toward patients reestablishing some normalcy in their daily lives.

There are treatments involving the spinal cord that are recommended for the most severe cases of chronic pain. They include stimulating the spinal cord with low-intensity electrical impulses and implanting a morphine pump to administer pain medication directly into the spinal fluid. None has been shown to have benefits significantly greater than the more common treatments.

A Civil War Legacy
While RSDS is thought by some to be a rare and recently discovered condition, it actually has a long history. Doctors who treated the Civil War wounded describe an RSDS-like ailment. Since that time, similar collections of symptoms have been recorded in medical literature under a variety of names. It all suggests a long (and painful) history for RSDS.