Fibromyalgia syndrome (FMS) is a non-articular rheumatic disease, most patients have typical diffuse generalized pain with symptoms lasting more than 3 months, mostly in women, most commonly at the age of onset 25-45 years. Clinical manifestations are pain and stiffness in multiple areas of the musculoskeletal system with pressure points in specific areas. Fibromyalgia syndrome can occur secondary to trauma, various rheumatic diseases such as osteoarthritis, rheumatoid arthritis and various non-rheumatic diseases (e.g. hypothyroidism, malignancy). This type of fibromyalgia syndrome is called secondary fibromyalgia syndrome, or primary fibromyalgia syndrome if it is not accompanied by other disorders.
I. Clinical manifestations.
1. Main symptoms: widespread pain throughout the body is a symptom that all patients with fibromyalgia syndrome have. Although some patients complain of only one or a few pains, 1/4 of them have more than 24 pain sites. The disease is widespread throughout the body, especially in the medial skeleton (neck, thoracic spine, lower back) and in the scapular and pelvic girdles. Other common sites are, in order, the knee, head, elbow, ankle, foot, upper back, mid-back, wrist, hip, thigh and calf. Most patients describe this pain as stabbing and distressing. Another symptom that all patients have is the widespread presence of pressure points that are present in tendons, muscles, and other tissues, often in a symmetrical distribution. The patient’s response to “pressure” is different from that of a normal person at the site of the pressure point, but there is no difference in other areas.
2. Characteristic disease: This group of symptoms includes sleep disturbance, fatigue and morning stiffness. About 90% of the patients have sleep disorder, which is characterized by insomnia, wakefulness, dreaminess, and lack of energy. 50-90% of the patients have fatigue, and about half of them have fatigue so severe that they feel “too tired to work”. Morning stiffness is seen in 76-91% of patients, and its severity is related to sleep and disease activity.
3. Common symptoms: The most common symptoms in this group are numbness and swelling. Patients often complain of joint and peri-articular swelling, but there are no objective signs. This is followed by headache and irritable bowel syndrome. Headache can be classified as migraine or non-migrainous headache, the latter being a dull, compressive pain in the occipital region or throughout the head. Psychological abnormalities including depression and anxiety are also more common. The above symptoms are often aggravated by cold and humid weather, mental tension and overexertion. Local heat, mental relaxation, good sleep and moderate activity can reduce the symptoms.
4.Mixed symptoms: primary fibromyalgia syndrome is rare, and most patients with fibromyalgia syndrome suffer from some kind of rheumatic disease at the same time. At this time, the clinical symptoms are the intertwining and overlapping of the two symptoms. Fibromyalgia syndrome often makes the coexisting rheumatologic symptoms appear more severe, and failure to recognize this condition often leads to overtreatment and examination of the latter.
Unless combined with other diseases, pre-fibromyalgia syndrome usually has no laboratory abnormalities. However, patients with fibromyalgia syndrome have been reported to have increased IL-1 levels, decreased natural killer cell and serotonin activity, and increased concentrations of substance P in the cerebrospinal fluid. Raynaud’s phenomenon is present in 1/3 of patients with drugs, and in this group of patients there may be positive antinuclear antibodies and reduced C3 levels.
II. Diagnosis
1.Generalized pain lasting for more than 3 months: generalized pain is considered when there is simultaneous pain in the left and right side of the body, upper and lower parts of the waist and the medial skeleton (cervical or anterior or thoracic spine or lower back).
2. Pressing with the thumb (the pressing pressure is about 4kg) at least 11 of the 18 pressure points are painful. These 18 (9 pairs) pressure points are: the suboccipital muscle attachment; the midpoint of the upper edge of the trapezius muscle; the front of the transverse space of the 5th to 7th cervical vertebrae; the beginning of the supraspinatus muscle, near the medial edge above the scapular spine; the distal 2cm of the lateral epicondyle of the humerus; the junction of the second rib and cartilage, just at the lateral upper edge of the junction; the upper quadrant of the buttocks, at the anterior hip crease; the posterior aspect of the greater trochanter; and the proximal side of the medial fat pad joint crease line of the knee. If the above two conditions are satisfied at the same time, fibromyalgia syndrome can be diagnosed.
Differential diagnosis
1. Psychogenic rheumatic pain: fibromyalgia syndrome is easily confused with psychogenic rheumatism, but they have significant differences. Psychogenic rheumatism has symptoms with emotional overtones. For example, the pain is described as severe pain like cutting and burning, or described as numbness, tightness, needle-like or compressive pain. These symptoms are often vaguely localized. Variable, without anatomical basis, and unaffected by weather or activity, patients often have mental or emotional disturbances such as psychoneurosis, depression, schizophrenia, or other psychiatric disorders. It is important to distinguish between the two, as the former is more difficult to manage and often requires treatment by a psychiatrist.
2. Chronic fatigue syndrome: Chronic fatigue syndrome includes chronic active EBV infection and idiopathic chronic fatigue syndrome. It is characterized by fatigue and weakness, but lacks an underlying cause. Examination of patients for low-grade fever, pharyngitis, swollen cervical or axillary lymph nodes, and determination of anti-EB virus envelope antigen antibody IgM can help identify the two.
3. Rheumatic polymyalgia: Rheumatic polymyalgia manifests as widespread neck, scapular girdle, back and pelvic girdle pain. However, it can be differentiated from fibromyalgia syndrome according to the characteristics of fast blood sedimentation, mostly seen in elderly people over 60 years old, synovial biopsy showing inflammatory changes, and sensitivity to hormones.
4, rheumatoid arthritis: patients with RA and fibromyalgia syndrome both have generalized pain, stiffness and joint swelling sensation. However, there is no objective evidence of swelling in the joints of fibromyalgia anterior syndrome, which has shorter morning stiffness than RA, and laboratory tests including rheumatoid factor, blood sedimentation, and joint x-ray are also political. The distribution of pain in fibromyalgia syndrome is wider, less confined to joints, and mostly located in the lower back, thighs, abdomen, head and hips, while the pain in RA is mostly distributed in the wrists, fingers and toes.
5, myofascial pain syndrome: myofascial pain syndrome, also known as limited fibrositis, also has academic pressure points, easily confused with fibromuscular anterior point sign. However, there are differences in diagnosis, treatment and prognosis between the two.
The pressure point in myofascial pain syndrome is usually called the point of excitation, and pressure on this point causes pain to radiate to other areas. Although the patient feels pain, they may not be aware of the excitation point anywhere.
Myofascial syndromes usually have only one or a few localized trigger points. The point of excitation originates in the muscle, and the affected muscle is restricted in movement, and pain can be caused by passive pulling or active contraction of the muscle. Local closure of the excitation points with 1% procaine can temporarily eliminate the pain. It is different from fibrositis in that there is no widespread pain, stiffness or fatigue. However, if persistent pain causes stage IV sleep disturbance, myofascial syndrome may evolve into fibromyalgia syndrome. Myofascial syndrome is usually caused by trauma or overexertion and generally has a better prognosis.
IV. Treatment
Fibromyalgia syndrome is an idiopathic disease whose pathophysiology is still unknown, and therefore there are few treatments for it. Its main clinical manifestation is diffuse chronic pain, and there are no objective signs other than “pressure points”. Therefore, it is not only difficult to choose the treatment, but also to evaluate the efficacy. The current treatment focuses on improving the sleep state, reducing the sensitivity of the nociceptive receptors, and improving the blood flow to the muscles.
One of the most important aspects of treatment is to provide comfort and explanation to the patient. Telling the patient that it is not a life-threatening disease and does not cause lifelong disability relieves the patient’s anxiety and depression.
In terms of pharmacological treatment, most authors report that the tricyclic antidepressants amitriptyline and aminophenazone are currently the ideal drugs for the treatment of this disease. Amitriptyline 10 mg, which can be slowly increased to 20-30 mg according to the can be slowly increased to 20-30 mg, or aminophene 10-40 mg, both are taken once before bedtime. The side effects are dry mouth, sore throat and constipation, which are mostly tolerated by patients due to the small dose.
In recent years, S-adenosylmethionine has been found to be effective in the treatment of fibromyalgia syndrome. It is the methyl arch of many methylation reactions in brain tissue and has antidepressant effect.
Other treatments such as silver needle conduction therapy, local sympathetic nerve block, pain point closure, transcutaneous nerve stimulation, interferential electrical stimulation, acupuncture, and aminomo can be tried. The efficacy and mechanism of these treatments await further study.