Complex regional pain syndrome is also known as complex regional pain syndrome or CRPS for short. The term replaces the synonymously used terms Sudeck’s disease, sympathetic reflex dystrophy, Sudeck’s dystrophy, and algodystrophy.
What is complex regional pain syndrome?
Complex regional pain syndrome occurs after soft tissue injury or after nerve injury. The syndrome often develops after a fracture. Although the term is actually obsolete, CRPS is still referred to as Sudeck’s disease. The name goes back to the Hamburg surgeon Paul Sudeck, who discovered the disease. In CRPS, sensory, motor, autonomic and trophic disturbances can develop. The course of the disease varies greatly depending on the patient. The diagnosis is also difficult. Therapy depends on the severity of the syndrome. Possible treatment methods include physiotherapy, manual therapy, lymphatic drainage, or invasive procedures such as epidural spinal cord stimulation.
Causes
The exact origin of complex regional pain syndrome is not yet clear. Presumably, the healing process in the injured tissue is impaired. The syndrome occurs after external effects such as trauma, inflammation, or surgery. The severity of CRPS does not depend on the severity of the injury. Complex regional pain syndrome occurs more frequently in the upper extremities than in the lower extremities. Women are affected more frequently than men. The syndrome is particularly common after distal radius fractures, fractures of the radius near the wrist. It is thought that an inflammatory reaction occurs in which various inflammatory mediators are released. These mediators are not fully cleared, so they prolong the neurogenic inflammatory response. The inflammatory mediators are also released in the central nervous system. This sensitizes the central pain-processing neurons. A centrally induced dysfunction of the sympathicotonic nervous system also causes circulatory disturbances and an increased tendency of the skin to sweat. The vessels constrict and connections form between arterial and venous vessels (arterio-venous shunts). As a result, the tissue is supplied with too little oxygen. Hypoxia develops, resulting in increased metabolic waste products. The resulting acidosis intensifies the pain. Similar to phantom limb pain, which can occur after limb amputation, cortical restructuring occurs in complex regional pain syndrome. Individual representational areas in the cerebral cortex change. As a result, pain expands and occurs across different nerve supply areas. There is also evidence of a genetic predisposition. For a long time, a psychological component was also suspected. Whether this is really the case has not yet been conclusively clarified. However, studies show that CRPS occurs more frequently after stressful life events.
Symptoms, complaints, and signs
Complex regional pain syndrome can be divided into two forms. In CRPS type I, trauma is present without nerve injury. CRPS type II occurs after trauma with nerve injury. Within the first three months, only nonspecific symptoms such as swelling, redness, pain, or warmth appear. Functionality of the affected limb may also be limited. After three to six months, dystrophy with joint stiffness develops. The final stage of complex regional pain syndrome is atrophy. After six to twelve months, no function is present. However, this classification is now highly controversial, as many patients have a divergent disease course. In many patients, there is weakness in the affected arm or leg. In the acute stage, the weakness is the result of pain and swelling. In the chronic stage, contractures and fibrosis limit mobility. Many patients also suffer from muscle tremors. Myoclonias are also observed. Hyperalgesia also develops in most patients. Pain sensitivity is greatly increased. Patients react with pain even to non-painful touch. Three out of four patients also suffer from pain at rest. Feelings of numbness or strangeness are also evident.At the beginning of the disease, there are almost always the typical signs of inflammation such as redness and swelling. If the condition becomes chronic, the affected extremities turn blue and become cold. Half of all sufferers have an increased tendency to sweat. This phenomenon is also known as hyperhidrosis. In the acute stage of the syndrome, hair and nails grow more in the affected area. Later, the growth turns into the opposite. In particularly severe cases, the musculature may completely regress. Due to this atrophy, severe movement restrictions develop.
Diagnosis and course of the disease
A diagnosis is made primarily on the basis of clinical appearances. Imaging techniques such as x-ray or scintigraphy provide additional information. Radiographs show patchy lightening caused by decreased calcium salt content in the bone. As chronicity progresses, these lightenings increase. However, the patchy decalcifications appear no earlier than eight weeks after the onset of the disease and are therefore not suitable for early diagnosis. Magnetic resonance imaging reveals soft tissue edema, thickening of the skin, fibrotic changes, and joint effusions. However, many CRPS cases are not detected due to low sensitivity. Skeletal scintigraphy reveals typical changes relatively early. For example, the ligamentous multiple stores near the joints are particularly noticeable.
Complications
Complex regional pain syndrome is usually itself a complication. It may arise as a result of a fracture. The syndrome, formerly known as Sudek’s disease, may also occur as a postoperative consequence of clubfoot surgery. In this case, it is a postoperative complication. The treatment of such complications is complex depending on the location of the symptoms and pain. As a result of complex regional pain syndrome, there may be numbness, limitation of movement, and chronicity of symptoms. In the chronic course, high-grade inactivity osteoporosis may occur. The affected bones increasingly degrade. They become porous. The muscle tissue can also degrade as a result of chronification of the complex regional pain syndrome. This also results in movement restrictions. The problem is that a medical professional can often only notice the changes to the bone structures when they have already reached a certain degree of severity. As a result, many CRPS cases are not initially recognized. This in turn has consequences. These often manifest themselves as late effects of trauma for the rest of the patient’s life. However, since sequelae such as complex regional pain syndrome are rather rare, the risk of non-treatable complications is statistically rather small. In addition, the treatment of surgical trauma can already prevent the occurrence of complex regional pain syndrome. Under regional anesthesia, complex regional pain syndrome appears to develop less frequently.
When should you see a doctor?
If persistent pain occurs after an injury, it needs to be evaluated by a primary care physician or a sports medicine physician and treated if necessary. Pain at rest and pressure pain around the joints indicate a complex regional pain syndrome. This resolves on its own in individual cases, but medical treatment is usually required. The affected person should consult a doctor and have the symptoms clarified before serious complications develop. Medical advice is required at the latest when swelling or circulatory problems are added to the pain. Lack of strength and stiffness indicate that the disease is already more advanced. The affected person should consult the general practitioner immediately. Psychological accompanying symptoms must be treated by a therapist. Sudeck’s disease occurs mainly after sprains, contusions, bruises or surgery-related injuries. The disease can also occur after vascular occlusions and dislocations. Anyone who belongs to the risk groups must immediately inform the responsible physician. In addition to the family physician, a sports medicine specialist or an internist may be called in.
Treatment and therapy
The therapy of complex regional pain syndrome is very long. The basis of therapy is physiotherapeutic interventions appropriate to the stage. Occupational therapy can also be used to restore everyday function.Biphosphonates, corticosteroids, tricyclic antidepressants, nonopioid analgesics, or opioids are frequently used for drug therapy.
Outlook and prognosis
Assessments regarding the prognosis for complex regional pain syndrome are not yet clear due to a lack of data. Until now, physicians assumed that complex regional pain syndrome developed posttraumatically as a result of surgery- or other-related damage to an extremity. The premise was that avoidance of such damage should be sought or that early multimodal pain management was appropriate. Trauma, overly tight bandages, poorly healed fractures, or other factors are present as causes in complex regional pain syndrome. However, the lingering pain cannot be adequately explained by these injuries. Today, physicians assume that regression of the pain syndrome is only possible with early diagnosis and therapy. However, complex regional pain syndrome often leads to a chronic course with a poor prognosis. The pain virtually takes on a life of its own without being explained by its cause. It is discussed whether a genetic disposition, a disturbed pain perception, psychological concomitant diseases or a painful therapeutic intervention are responsible for this. Until physicians understand the complex regional pain syndrome, the prognosis of chronic pain will not improve. It stands to reason that the cause of complex regional pain syndrome is often blamed on psychological factors. According to the prevailing medical paradigms, the symptom should disappear if its cause has been corrected.
Prevention
Complex regional pain syndrome cannot be prevented. The earlier the condition is detected, the better the prognosis. Therefore, if CRPS is suspected, a specialist should be consulted as soon as possible.
Follow-up care
In this syndrome, the possibilities for aftercare are limited in many cases, since first and foremost the cause of the pain must be treated properly and, above all, sustainably. Self-cure cannot occur in this case, so the patient should see a doctor at the first signs of the disease to prevent further complications and a further worsening of the symptoms. As a rule, early diagnosis always has a very positive effect on the further course of the disease. Most people affected by this disease are dependent on taking various medications. It is always important to ensure that the medication is taken regularly and in the correct dosage. Likewise, all instructions of the doctor should be followed. In case of any uncertainties or side effects, a doctor should be consulted first. Furthermore, measures of a physiotherapy can be very helpful in this disease. Many of the exercises can also be done at home, which speeds up the treatment. In general, support and help from relatives also has a positive effect on the course of this syndrome, and in the process can also prevent depression and other psychological complaints.
This is what you can do yourself
The steps that sufferers of complex regional pain syndrome can take to reduce the discomfort depend on its cause and the type of medical treatment they receive. Generally, pain can be reduced by acute measures such as cooling compresses and rest. Naturopathy offers various painkillers that can also help to alleviate the discomfort. For example, calendula ointment or gentle infusions with chamomile have proven effective. Homeopathic remedies include belladonna and arnica. In addition, physiotherapy is always indicated for CRPS. Treatment by a therapist or sports medicine specialist can be supported at home by targeted exercise. For this purpose, the patient should draw up an exercise plan together with the specialist and implement it in a targeted manner. Further measures depend on the cause of the complaints. For example, occupational therapy can be performed after a stroke, which can also be continued at home. In severe cases, aids such as crutches or a wheelchair must be organized. In addition, regular visits to the doctor are indicated, because only close medical monitoring can check the state of health and intervene quickly in the event of complaints and complications.
