Күрделі аймақтық ауырсыну синдромы және оның түрлері

Array of painful conditions in humans

Complex regional pain syndrome (CRPS Type 1 and Type 2) is a severe form of chronic pain, in which pain from a physical trauma outlasts the expected recovery time. The symptoms of types 1 and 2 are the same except type 2 is associated with nerve injury. Usually starting in a limb, CRPS manifests as pain, swelling, limited range of motion, and/or changes to the skin and bones. It may initially affect one limb and then spread throughout the body; 35% of affected individuals report symptoms throughout the body. Two types are thought to exist: CRPS type 1 (previously referred to as reflex sympathetic dystrophy) and CRPS type 2 (previously referred to as causalgia). It is possible to have both types. Amplified musculoskeletal pain syndrome, a condition that is similar to CRPS, primarily affects pediatric patients, falls under rheumatology and pediatrics, and is generally considered a subset of CRPS type I.

The classification system in use by the International Association for the Study of Pain (IASP) divides CRPS into two types based on the presence or absence of measurable nerve pathophysiology. +International Association for the Study of Pain ClassificationTypeClinical findingsSynonymsType ICRPS without evidence of neuropathology in the affected limb. This accounts for about 90% of CRPS. reflex sympathetic dystrophy, RSD, Sudeck's atrophyType IICRPS with evidence of neuropathology in the affected limb. causalgia

Clinical features of CRPS have been found to be inflammation resulting from the release of certain pro inflammatory chemical signals from surrounding nerve cells; hypersensitization of pain receptors; dysfunction of local vasoconstriction and vasodilation; and maladaptive neuroplasticity. Moving or touching the limb is disproportionately painful (allodynia). Other findings are aspects of disuse including swelling, stiffness (limited range of motion), and disuse related changes to the skin (temperature, color, sweating, texture) and bones (disuse osteoporosis). A prior concept of CRPS having three stages is no longer in wide use. The trend is now to consider distinct sub types of CRPS. Investigators estimate that 2–5% of those with peripheral nerve injury, will develop CRPS. In addition, some studies have indicated that cigarette smoking was strikingly present in patients and is statistically linked to RSD. This may be involved in its pathology by enhancing sympathetic activity, vasoconstriction, or by some other unknown neurotransmitter related mechanism. This hypothesis was based on a retrospective analysis of 53 patients with RSD, which showed that 68% of patients were smokers, compared to only 37% of the control population. The results are preliminary and are limited by their retrospective nature. 7% of people who have CRPS in one limb later develop it in another limb.

No specific test is available for CRPS, which is diagnosed primarily through observation of the symptoms. However, thermography, sweat testing, X rays, electrodiagnostics, and sympathetic blocks can be used to build up a picture of the disorder. Diagnosis is complicated by the fact that some patients improve without treatment. A delay in diagnosis and/or treatment for this syndrome can result in severe physical and psychological problems. Early recognition and prompt treatment provide the greatest opportunity for recovery.

Presently, established empirical evidence suggests against thermography's efficacy as a reliable tool for diagnosing CRPS. Although CRPS may, in some cases, lead to measurably altered blood flow throughout an affected region, many other factors can also contribute to an altered thermographic reading, including the patient's smoking habits, use of certain skin lotions, recent physical activity, and prior history of trauma to the region. Also, not all patients diagnosed with CRPS demonstrate such "vasomotor instability"—particularly those in the later stages of the disease. Thus, thermography alone cannot be used as conclusive evidence for—or against—a diagnosis of CRPS and must be interpreted in light of the patient's larger medical history and prior diagnostic studies. In order to minimise the confounding influence of external factors, patients undergoing infrared thermographic testing must conform to special restrictions regarding the use of certain vasoconstrictors (namely, nicotine and caffeine), skin lotions, physical therapy, and other diagnostic procedures in the days prior to testing. Patients may also be required to discontinue certain pain medications and sympathetic blockers. After a patient arrives at a thermographic laboratory, he or she is allowed to reach thermal equilibrium in a 16–20 °C, draft free, steady state room wearing a loose fitting cotton hospital gown for approximately twenty minutes. A technician then takes infrared images of both the patient's affected and unaffected limbs, as well as reference images of other parts of the patient's body, including his or her face, upper back, and lower back. After capturing a set of baseline images, some labs further require the patient to undergo cold water autonomic functional stress testing to evaluate the function of their autonomic nervous system's peripheral vasoconstrictor reflex. This is performed by placing a patient's unaffected limb in a cold water bath (approximately 20 °C) for five minutes while collecting images. In a normal, intact, functioning autonomic nervous system, a patient's affected extremity will become colder. Conversely, warming of an affected extremity may indicate a disruption of the body's normal thermoregulatory vasoconstrictor function, which may sometimes indicate underlying CRPS.

Scintigraphy, plain radiographs, and magnetic resonance imaging may all be useful diagnostically. Patchy osteoporosis (post traumatic osteoporosis), which may be due to disuse of the affected extremity, can be detected through X ray imagery as early as two weeks after the onset of CRPS. A bone scan of the affected limb may detect these changes even sooner and can almost confirm the disease. Bone densitometry can also be used to detect changes in bone mineral density. It can also be used to monitor the results of treatment since bone densitometry parameters improve with treatment.

Ultrasound based osteodensitometry (ultrasonometry) may be potential future radiation free technique to identify reduced bone mineral density in CRPS. Both EMG and NCS involve some measure of discomfort. EMG involves the use of a tiny needle inserted into specific muscles to test the associated muscle and nerve function. Both EMG and NCS involve very mild shocks that in normal patients are comparable to a rubber band snapping on the skin. Although these tests can be very useful in CRPS, thorough informed consent must be obtained prior to the procedure, particularly in patients experiencing severe allodynia. In spite of the utility of the test, these patients may wish to decline the procedure to avoid discomfort.

Type I, formerly known as reflex sympathetic dystrophy (RSD), Sudeck's atrophy, or algoneurodystrophy, does not exhibit demonstrable nerve lesions. As the vast majority of patients diagnosed with CRPS have this type, it is most commonly referred to in medical literature as type I. Type II, formerly known as causalgia, has evidence of obvious nerve damage. Despite evidence of nerve injury, the cause or the mechanisms of CRPS type II are as unknown, as the mechanisms of type I. Patients are frequently classified into two groups based upon temperature: "warm" or "hot" CRPS in one group and "cold" CRPS in the other group. The majority of patients (about 70%) have the "hot" type, which is said to be an acute form of CRPS. Cold CRPS is said to be indicative of a more chronic CRPS and is associated with poorer McGill Pain Questionnaire scores, increased central nervous system reorganisation, and a higher prevalence of dystonia.

Vitamin C supplementation may be useful in prevention of the syndrome following fracture of the forearm, foot, or ankle.

Treatment of CRPS often involves a number of modalities.

Physical and occupational therapy have low quality evidence to support their use. Physical therapy interventions may include transcutaneous electrical nerve stimulation, progressive weight bearing, graded tactile desensitization, massage, and contrast bath therapy. In a retrospective cohort (unblinded, non randomised and with intention to treat) of fifty patients diagnosed with CRPS, the subjective pain and body perception scores of patients decreased after engagement with a two week multidisciplinary rehabilitation programme. The authors call for randomised controlled trials to probe the true value of multidisciplinary programs for CRPS patients.

Mirror box therapy uses a mirror box, or a stand alone mirror, to create a reflection of the normal limb such that the patient thinks they are looking at the affected limb. Movement of this reflected normal limb is then performed so that it looks to the patient as though they are performing movement with the affected limb. Mirror box therapy appears to be beneficial at least in early CRPS. However, beneficial effects of mirror therapy in the long term is still unproven.

Tentative evidence supports the use of bisphosphonates, calcitonin, and ketamine. Nerve blocks with guanethidine appear to be harmful. Intramuscular botulinum injections may benefit people with symptoms localized to one extremity.

Ketamine, a dissociative anesthetic, appears promising as a treatment for CRPS. It may be used in low doses if other treatments have not worked. No benefit on either function or depression, however, has been seen. To date so far, no long term studies of oral opioid use in treating neuropathic pain, including CRPS, have been performed. The consensus among experts is that opioids should not be a first line therapy and should be considered only after all other modalities (e. g., non opioid medications, physical therapy, and procedures) have been trialed.

Spinal cord stimulation appears to be an effective therapy in the management of patients with CRPS type I (level A evidence) and type II (level D evidence). Although they improve patient pain and quality of life, evidence is unclear regarding effects on mental health and general functioning. Dorsal root ganglion stimulation is a type of neurostimulation that is effective in the management of focal neuropathic pain. The FDA approved its use in February 2016. The ACCURATE Study demonstrated superiority of dorsal root ganglion stimulation over spinal (dorsal column) stimulation in the management of CRPS and causalgia.

Surgical, chemical, or radiofrequency sympathectomy—interruption of the affected portion of the sympathetic nervous system—can be used as a last resort in patients with impending tissue loss, edema, recurrent infection, or ischemic necrosis. However, little evidence supports these permanent interventions to alter the pain symptoms of the affected patients, and in addition to the normal risks of surgery, such as bleeding and infection, sympathectomy has several specific risks, such as adverse changes in how nerves function.

No randomized study in medical literature has studied the response with amputation of patients who have failed the above mentioned therapies and who continue to be in pain. Nonetheless, on average, about half of the patients will have resolution of their pain, while half will develop phantom limb pain and/or pain at the amputation site. As in any other chronic pain syndrome, the brain likely becomes chronically stimulated with pain, and late amputation may not work as well as it might be expected. In a survey of 15 patients with CRPS type 1, 11 responded that their lives were better after amputation.

Cannabidiol (CBD), despite evidence of very low quality, is proposed to relieve pain.

The prognosis in CRPS is improved with early and aggressive treatment; with the risk of chronic, debilitating pain being reduced with the early treatment. If treatment is delayed, however, the disorder can quickly spread to the entire limb, and changes in bone, nerve, and muscle may become irreversible. The prognosis is worse with the chronic "cold" form of CRPS and with CRPS affecting the upper extremities.

CRPS can occur at any age, with the average age at diagnosis being 42. It affects both men and women; however, CRPS is three times more frequent in females than males. with a recent observational study finding an incidence of 1.16/100,000 among children in Scotland.

The condition currently known as CRPS was originally described by Ambroise Paré. He successfully treated a severe and persistent pain syndrome that occurred to the French King Charles IX of Valois after a limb phlebotomy During the American Civil War, Silas Weir Mitchell is sometimes also credited with inventing the name "causalgia". However, this term was actually coined by Mitchell's friend Robley Dunglison from the Greek words for heat and for pain. Contrary to what is commonly accepted, it emerges that these causalgias were certainly major by the importance of the vasomotor and sudomotor symptoms but stemmed from minor neurological lesions. In the 1940s, the term reflex sympathetic dystrophy came into use to describe this condition, based on the theory that sympathetic hyperactivity was involved in the pathophysiology. In 1959, Noordenbos observed in causalgia patients that "the damage of the nerve is always partial." Misuse of the terms, as well as doubts about the underlying pathophysiology, led to calls for better nomenclature. In 1993, a special consensus workshop held in Orlando, Florida, provided the umbrella term "complex regional pain syndrome", with causalgia and RSD as subtypes.

The National Institute of Neurological Disorders and Stroke (NINDS), a part of the National Institutes of Health, supports and conducts research on the brain and central nervous system, including research relevant to RSDS, through grants to major medical institutions across the country. NINDS supported scientists are working to develop effective treatments for neurological conditions and ultimately, to find ways of preventing them. Investigators are studying new approaches to treat CRPS and intervene more aggressively after traumatic injury to lower the patient's chances of developing the disorder. In addition, NINDS supported scientists are studying how signals of the sympathetic nervous system cause pain in CRPS patients. Using a technique called microneurography, these investigators are able to record and measure neural activity in single nerve fibers of affected patients. By testing various hypotheses, these researchers hope to discover the unique mechanism that causes the spontaneous pain of CRPS, and that discovery may lead to new ways of blocking pain. Other studies to overcome chronic pain syndromes are discussed in the pamphlet "Chronic Pain: Hope Through Research", published by the NINDS. Research into treating the condition with mirror visual feedback is being undertaken at the Royal National Hospital for Rheumatic Disease in Bath. Patients are taught how to desensitize in the most effective way, then progress to using mirrors to rewrite the faulty signals in the brain that appear responsible for this condition. However, while CRPS can go into remission, the chance of it reoccurring is significant. The Netherlands has the most comprehensive program of research into CRPS, as part of a multimillion Euro initiative called TREND. German and Australian research teams are also pursuing better understanding and treatments for CRPS.

CRPS has also been described in non human animals, such as cattle.