Causes of joint pain

Pain in the affected joint (arthralgia) occurs as a result of irritation of the nerve endings in its various structures, excluding the articular cartilage, which has no nerve endings and vessels. By polyarthralgia means the presence of pain in 5 or more joints.

Pain in joints is usually combined with signs of joint inflammation, soft tissue and / or bone tendon attachment sites (entesitis), less often biomechanical or neurogenic. However, in many cases with rheumatic diseases, pain is associated with several mechanisms simultaneously. For example, with osteoarthritis, pain is often biomechanical, inflammatory and vascular in nature and can be associated with psychoemotional disorders.

When a patient is questioned, the doctor must receive answers to a number of very important questions: it is necessary to clarify the localization of pain, its irradiation, prevalence and depth, determine the nature of pain (stitching, cutting, aching, burning, pulsating, etc.). The duration of the pain syndrome, the frequency of pain, its rhythm during the day (including the presence of so-called light intervals, that is, periods when pain is absent), the intensity of the pain syndrome, the constant pain or increasing is specified. The doctor tries to find out what the patient is experiencing the appearance of pain in the joint. Risk factors for the development of lesions of the osteoarticular apparatus are most often the infectious disease transferred on the previous day (acute respiratory viral infections, salmonellosis, etc.), exacerbation of chronic foci of infection (chronic tonsillitis, sinusitis, etc.), overload or joint damage, use of glucocorticoids background of their use, osteonecrosis of the bone is possible). The appearance of an articular syndrome after an infectious disease, an allergic reaction, allows the doctor to suspect the inflammatory nature of joint damage - arthritis. The presence in the anamnesis of information about permanent traumatization, excessive and prolonged physical exertion on the locomotor system in the absence of inflammation (for example, in athletes) speaks rather about the degenerative-dystrophic nature of the pathological process. The connection of the pain syndrome with certain movements, such as climbing or descending the stairs, is also specified. Pain sensations in the bones (ossalgia) and joints can be associated with overtraining in sports, with changing weather conditions or with some other reason.

Do not forget the doctor and the so-called arthralgia of inorganic etiology.

Family history and information on the patient's heredity contribute to the correct diagnosis of diseases of the osteoarticular system, which can be either hereditary (syndrome of generalized exostosis of long tubular bones, metaphyseal dysplasia, generalized chondrodystrophy, Ehlers-Danlos syndrome, Marfan syndrome, etc.). , or have a hereditary predisposition (for example, rheumatoid arthritis).

As for the algorithm for diagnosing articular syndrome, here, for a basis, one can take such an important symptom as pain in the joint:

1. Pain in the joints of a permanent nature, increasing after a load, with the presence of morning stiffness is characteristic of a number of diseases, such as rheumatoid arthritis, reactive arthritis, psoriatic arthropathy, i.e. For a group of inflammatory diseases. But it should be noted that the morning stiffness characterizes not only inflammatory diseases, but also metabolic-dystrophic, that is why it occurs, including in cases of osteoarthrosis - primary and secondary.
2. Starting (mechanical) joint pains are more common in osteoarthritis. Pain syndrome occurs with a large load on the joint, or at the beginning of the load, or as the physical load increases by the end of the day.
3. Pains that rapidly increase in the joints of the first finger, with rapidly progressive edema, fever, often occur in the onset of gout attacks. Strangely enough, in the presence of this seemingly simplest and brightest characteristic of the pain syndrome, gout, nevertheless, of all the pathological conditions accompanying the joint syndrome, the worst is diagnosed.
4. The pains in joints of a permanent nature with localization in the spine are intense, burning, with no change in intensity being most characteristic of the paraneoplastic process.

Thus, the chronic pain syndrome in the joints includes a whole group of nosological forms, which is represented, first of all, by diseases of the musculoskeletal system. This includes inflammatory, metabolic-dystrophic joint diseases, secondary joint damage, joint damage in non-rheumatic diseases.

Inflammatory joint diseases include rheumatoid arthritis, a large group of reactive arthritis, psoriatic arthropathy, spondyloarthritis and gouty arthritis.

To obmenno-dystrophic diseases of joints include osteoarthritis (osteoarthritis), gout (primary and secondary), osteoporosis, chondrocapacia, cholidropicinosis, hydroxyapatite arthropathy.

Secondary joint damage includes posttraumatic arthrosis and arthritis, osteoarthritis on the background of primary arthritis, paracancroznye arthritis, metastatic spinal lesions in diseases of the blood system, joint damage in avitaminosis, lung diseases, amyloidosis.

It was once thought that the presence of rheumatoid arthritis does not involve the addition of a second disease belonging to the group of secondary osteoarthritis in the background of this disease. But now it is known that he really accompanies the inflammatory diseases of the joints, that is why he is included in the group of osteoarthrosis against the background of primary arthritis.

Allergic diseases (serum sickness, drug disease and other allergic conditions), metabolic disorders (amyloidosis, ochrinoz, hyperlipidemia, hemahromatosis), congenital defects in connective tissue metabolism (Marfan syndrome, Eders-Danlos syndrome, mucopolysaccharidosis) lead to secondary arthropathies in non-rheumatic diseases. , paraneoplastic diseases, endocrine diseases (diabetes, acromegaly, hyperparathyroidism, hyperthyroidism, hypothyroidism), leukemia and a group of lymphoproliferative diseases ani. Articular syndrome in this list of diseases occurs in the form of inflammatory joint damage or in the variant of metabolic-dystrophic diseases.

Each of these nosological forms has its own flow characteristics, but they are united by one and the most important symptom complex, which is represented, first of all, by arthralgia. Arthralgia is necessarily present in each of these diseases.

Joint pain can mimic fibromyalgia. Fibromyalgia is a syndrome of chronic (lasting more than 3 months), non-inflammatory and non-autoimmune diffuse pain of unknown etiology with characteristic painful points, revealed during physical examination. In this case, patients often complain of morning stiffness, fatigue, manifestations of the phenomenon of Raynaud and other subjective signs, characteristic of the inflammatory process. Physical examination and laboratory data do not reveal signs of inflammation or degenerative processes in the joints, bones and soft tissues. In the development of it, the importance of microtrauma and untrained muscles, an increase in the production of substance P, as well as the phenomenon of an increased number of alpha _2- adrenergic receptors in muscles, vessels of the fingers, lacrimal and salivary glands, is manifested by muscular pain due to relative ischemia, the Raynaud phenomenon and others. Fatigue and weakness in fibromyalgia are caused not by circulating cytokines, but by sleep disorders (alpha delta sleep). Fatigue and generalized pain in fibromyalgia are nonspecific symptoms and occur in many conditions.

Bruises, sprains, less often dislocations and fractures, especially in people who regularly engage in sports, may be accompanied by a symptomatology "masquerading as a true joint." The reason is the stretching and inflammation of the musculo-tendon structures. Overtraining in sports (football, athletics) is due to the emergence of patellofemoral stress syndrome. This condition develops when the process of unbending the repeatedly injured knee joint is violated and is characterized by a chronic pain syndrome. It is necessary to differentiate this pathology with chondromalacia of the patella.

Complaints about "cotton" in the joint area with knee injury can be a sign of a pathology such as meniscus injuries, anterior cruciate ligament, subluxation of the patella.

Differential diagnosis of arthralgias of organic and inorganic etiology

Organic causes	Functional disorders
Pain occurs during the day and at night Pain occurs on weekends and during holidays The pain is so strong that the patient is forced to interrupt the work Pain localized in the joint One-sided pain Patient is limping or refusing to walk Anamnestic data: signs of systemic disease, including weight loss, fever, night sweats, rashes on the skin, diarrhea	Pain occurs only at night Pain occurs mainly on working days The patient continues to lead a normal life Pain is localized between the joints Two-sided pain The gait does not change Anamnestic data: in all respects a healthy patient, there may be a history of minimal neurotic disorders

[1], [2], [3], [4]