What is Reflex sympathetic dystrophy?
Reflex sympathetic dystrophy is a complex medical condition typically occurs due to sympathetic nervous system disorder and characterized by pain, feel like a burning sensation, inflammation and severe vasomotor dysfunctionality. The condition develops rarely and usual incidence rate is high after surgery or trauma.
The onset of Reflex sympathetic dystrophy after cardiac stoke can cause upper limb immobility due to the hemiplegic upper limb which also leads to Reflex sympathetic dystrophy (RSD).
Sometimes the reason behind the onset of RSD is also non-identifiable. The RSD has several other clinical terms and complex regional pain syndrome (CRPS) is often used to describe the condition in detail.
The RSD or CRPS is often described as two types: Type: 1 and Type 2. This classification is based upon triggering factors of the condition, however both types contain similar symptoms with follow the same developmental consequences:
Acute phase or Stage 1
This stage is continued for 2-3 months, during this period hypersensitivity, burning sensation, pain while touches etc are the initial symptoms felt by the patient followed by stiffness of the joints, inflammation, redness, warmth temperature are gradually developed. The pain sensation is totally different than the normal injury and stay for prolonged periods.
Dystrophic Phase or Stage 2
The duration of this stage may vary from 3 to 12months. The tenderness of the skin increases with the reduction of wrinkles. The affected area becomes extended and pain is felt with wide area and touching increase the pain sensation. The skin temperature becomes lessened than the acute phase. The nails become easily breakable.
Atrophic Phase or Stage 3
This phase is developed over 1 year of the onset of the RSD. The dermatological changes are noticeable like increase dryness, stretching is more prominent, the skin become pale and texture is shiny. The increase stiffness may lead to immobility of the part. The Pain reduction occurs with the increase spreading area.
The affected area differs, mostly in case of reflex sympathetic dystrophy; the upper limb and shoulder joint are affected. Some individual may also develop this in both upper and lower limbs and sometimes the symptoms are localized in specific area such as at the hip joint or knee joints. The symptoms are similar to nerve injury and often misdiagnosed with this condition. The most prominent symptoms in case of RSD are as follows:
The affected area has severe pain sensation. The specificity of this pain is burning sensation along with pain. This distinctive pain is felt with fingers, palm, arm and shoulder. If the leg is affected then the knee and hip are mostly develop the pain, though the whole leg become affected.
The skin of the affected area becomes too much sensitive while touching and pain increases. The skin is sensitive with chancing of weather, it may get affected in both the condition means too hot or cold weather increase the sensitivity of the skin.
The chances of developing edema are high which increase the tenderness, and swelling of the affected area
The associated joint becomes stiff and gradually loses elasticity and leads to immobility of the affected area.
The function of the sympathetic nervous system is to regulate heart rate, vascular contraction, blood circulation and maintain blood pressure. Due to abnormality occurs in sympathetic nervous system causes the warm temperature of the body and also initiates excessive sweating and flushing.
Causes and patho-physiology
The Proper reason of development of the RSD is not clearly described yet. The cause of development of the Type 1 and Type 2 RSD is differing.
- Type 1 RSD is developed after injury, traumatic ailment, and surgical intervention. The incidence rate is high almost 90% in the case of Type 1.
Type 2 is developed after sympathetic nerve damage.
In general, when malfunctioned anomaly occurs between central nervous system with autonomic nervous system develops and leads to inflammatory conditions.
- Over activity of the sympathetic nervous system may cause due to genetic predisposition or individual have the tendency of over stimulation of the sympathetic nerves.
- Neurological illness which leads to neurological dysregulation of nociceptive impulses
- Cardiovascular problems cause an ischemic condition due to vasoconstriction which followed by formation of reflex arc and leads to vasospasm. Different inflammatory agents are secreted in this condition, such as histamine, bradikinin and serotonin, which can cause further pain, inflammation and stiffness.
- Cervical problems or neck injury also leads to neurological dysfunction, which leads to dysregulation of spinal nerves and affects the peripheral neurons.
The initial diagnosis is started during the discussion of medical history, sign and symptoms. Physical examination of the affected part also helps to understand the severity, as touching increases the pain. A series of diagnostic tests is conducted for confirming the RSD. The following are the possible tests which doctor can order:
- MRI for analyzing the alteration of tissue structure
- X-ray is conducted for checking the bone density
- Bone scan is also performed by injecting some specific radioactive substance intravenously at the affected area to get more visualization.
- Autonomic nervous system test can be conducted my checking skin temperature and blood circulation to the affected area in comparison with unaffected areas.
The early diagnosis and proper treatment can completely cure RSD. Following different treatments are available:
Steroidal drugs, Non-steroidal anti-inflammatory drugs, opioid analgesics are prescribed for reducing the pain. Anti-depressant drugs, anti-convulsants or anti-hypertensive drugs are prescribed depending upon the underlying cause of the RSD.
Hot and cold therapy helps to reduce the inflammation, some proper training of the exercise helps to improve mobility and lessen the pain. Direct electrical stimulation of the affected nerve can help to decrease the pain intensity.
Training of bio-feedback increases the bodily wakefulness and repose techniques which is beneficial for pain reduction.
- Tiny electrodes administration to the spinal cord by small surgical intervention can help to pain management.
- Pain pump administration at the spinal cord is another small surgical technique, where pain medication is gradually released for a sustained period to manage the pain.
Delayed diagnosis and untreated RSD lead further complications which are as follows:
- Atrophy (weakening of the associated tissue)
- Muscle stiffness can be observed due to restricted movement of the affected area of pain development.