The joint diseases. What is osteoarthritis? Symptoms and treatment

General information about joint diseases

In all joints of the human body, the articular surfaces of the bones (distal ends) are covered with cartilage. Cartilage has a smooth surface that, together with synovial fluid, promotes friction-free movement in the joint. Joints are surrounded by ligaments and muscles. Damage to articular cartilage over time leads to its degeneration and the development of diseases such as arthritis and arthrosis.

General information about arthrosis

Arthrosis is a chronic disease characterized by biochemical and morphological changes in the synovial membrane and joint capsule resulting from erosions, cartilage destruction, osteophytes on the bone edges, subchondral sclerosis and cysts detected by pathological, radiological and clinical examination methods. In osteoarthritis, the pathological process involves not only the cartilage itself, but also adjacent anatomic structures (capsule, ligaments, synovial sheath, bony structures under the cartilage and muscles around the joint).

Arthrosis:

This is a disease in which degenerative changes occur in the articular cartilage. Increased body weight, high load on the joints, etc. can cause the development of arthrosis. Arthrosis pain increases during movement, and the pain subsides during rest. The tissues around the joint swell, and over time, the joint deforms.

Arthritis:

It occurs as a result of cartilage destruction following infectious diseases that cause inflammation in the joint. The patient experiences pain at rest and on movement. These patients wake up in the morning with a sharp pain. The feelings in the joint area are: burning, stiffness, hyperemia (redness), and pain at rest and at night. There are about 200 diseases that are related to arthritis (osteoarthritis; rheumatoid arthritis; post-traumatic arthritis; arthritis following metabolic, endocrine, genetic and other diseases).

Prevalence of arthrosis

Arthrosis is a widespread joint disease. In the United States, the disease occurs in 7% of the population. Russian experts also voice similar figures. In our country, there is about the same situation. Arthrosis among men and women occurs with equal intensity. However, among young patients, men make up the majority, and among older patients, women make up the majority. Unlike normal arthritis, arthrosis of the interphalangeal joints occurs 10 times more often in women than in men. The risk of developing arthrosis increases with age. Statistically, arthrosis in patients under 45 years of age occurs in 2% of cases, 45-64 years of age in 30% of cases, and in those over 65 years of age in 85% of cases. The highest prevalence of arthrosis is arthrosis of the small joints of the wrist, the first metatarsophalangeal joint, arthrosis of the cervical and lumbar spine, including arthrosis of the hip and knee joints. However, because of the greater impact on the patient’s quality of life and ability to work, arthrosis of the larger joints has greater clinical importance.

What causes arthrosis?

In most cases, arthrosis occurs for no particular reason; this pathology is called idiopathic or primary pathology. Secondary arthrosis also occurs due to other conditions. The following are common causes of secondary arthrosis.

• Trauma (fracture, meniscus injury, torn ligaments, dislocation, etc.).
• Dysplasia (congenital anomalies of the hip, knee, ankle joints and joints of the upper extremities).
• Metabolic disorders.
• Autoimmune diseases (rheumatoid arthritis, lupus, etc.).
• Non-specific inflammation (acute purulent arthritis).
• Specific inflammation (tuberculosis, gonorrhea, syphilis, tick-borne encephalitis).
• Some endocrine disorders.
• Degenerative-dystrophic processes (Perthes disease and other osteochondropathies).
• Diseases with high joint mobility and weakness of the ligament apparatus.
• Blood diseases: diseases that are accompanied by bleeding into the joint cavity, such as hemophilia, etc.

Risk factors that cause osteoarthritis

• Age (over 60 years of age).
• Excessive weight (places constant strain on joints, causing premature damage to the articular surface).
• Excessive strain on one or more joints This may be due to working conditions, improper organization of training (especially if there is a history of joint trauma), some diseases, including those resulting from injuries (for example, excessive strain on the muscles of the arms and the healthy leg due to the use of a cane when limping).
• Surgical interventions on joints.
• Hereditary predisposition (presence of arthritis in close relatives).
• Imbalance of endocrine hormones in postmenopausal women.
• Lack of micronutrients.
• Neurodystrophic diseases in the cervical and lumbar parts of spinal column (shoulder and scapular periarthritis, iliopsoas syndrome).
• Exposure to toxic substances.
• A bad ecological environment.
• Repeated microtrauma of the joints.

Pathogenesis

Arthrosis is a polyethylological disease that is accompanied by a disturbance in the structure of cartilage tissue, due to many (not one specific) causes. Cartilage in a healthy joint is smooth and elastic. This promotes free movement of the articular surface, maintaining the right level of cushioning; as a result, the level of stress on adjacent structures (bones, ligaments, muscles and joint capsule) is reduced.

During arthrosis, the cartilage becomes coarser, the joint surfaces contact each other during movement, and over time the cartilage becomes thinner. Foci of small calcifications form on the cartilage edges. Under the cartilage, ossification (subchondral sclerosis) is observed. A cyst is formed in the central part of the joint, due to the presence of a cavity in it; the process of ossification begins around the cyst, due to the pressure of synovial fluid. During arthrosis, the joint capsule and synovial fluid become thickened due to permanent damage.

Lyphs form in the synovial tissue, and fibrous foci form in the capsule. Over time, cartilage thinning occurs, bone surfaces become deformed due to the disturbance of shape and function, and bone protrusions (osteophytes) form on their edges. As a result of the increased load on the ligaments and muscles, fibrous foci appear. The probability of damage to the ligamentous and muscular apparatus increases (sprain, partial or complete rupture of ligaments), and sometimes the joint goes into a state of subluxation. With the increase of cartilage damage, motor activity decreases sharply, and over time, ankylosis of the joint (articulation of the bone surfaces) is observed.

The illustration shows the stages of gonarthrosis

Definition

Depending on the localization, there is arthritis of the shoulder, elbow, wrist, hip, knee, ankle and other joints. Pathologies are divided into three groups, depending on their severity:

First degree: no visible morphological changes are found; only the composition of synovial fluid changes. Cartilage nutrition by synovial fluid is disturbed; Cartilage resistance to normal load is reduced. This results in inflammation and pain in the cartilage.

Second degree: The articular cartilage begins to break down, and bony protrusions appear on the edges of the articular surfaces. The pain is constant; the inflammation worsens and wanes. The muscles around the joints become weak and slightly dysfunctional.

Third stage: The cartilage of the joints is thinning, and there are large pockets of damage to the cartilage. The joint area is severely deformed, the anatomical axis of the limb changes direction, ligaments are shortened and their strength is reduced, thus causing pathological mobility and decreased physiological movement in the joint. The muscles around the joint become tense or shortened, and their ability to contract is reduced. Nutrition of the joints and periarticular tissues of the limb is disturbed.

X-ray shows deforming arthritis of the knee joint

What are the signs of osteoarthritis?

Osteoarthritis develops gradually. In the beginning, patients are disturbed during physical activity by a weak and not prolonged pain without certain localization. In some clinical cases, the first symptom appears on movement, and most of them refer to gonarthrosis and osteoarthritis of the shoulder joint. Most patients who suffer from osteoarthritis notice stiffness in the joint after rest, and note moderate pain on first movements. Because of the increased strain on the lower extremities, pain occurs in the opposite joint.

Pain is a constant symptom in osteoarthritis. A distinctive feature of osteoarthritis pain is its relationship to physical load and weather, as well as joint blockage accompanied by momentary sharp pain. Joint pain is primarily associated with exertion. During prolonged exertion (walking, running and standing in one place), the pain increases and decreases during rest. This is due to the cartilage’s reduced ability to maintain cushioning during movement. Nocturnal pain in arthritis is caused by venous stasis, also due to increased intra-articular pressure. Pain worsens under the influence of bad weather (increased dampness, decreased temperature and high atmospheric pressure). The most characteristic feature of pain is the initial (starting) pain on movements (after resting, passing during movement). The cause of starter pain in arthritis is detritus, which is tissue that has formed as a result of the destruction of cartilage tissue located on the articular surface. As a result of the movement, the detritus moves into the joint cavity, and thus the pain goes away. Joint blockage is accompanied by acute pain. It is caused by articular muscle (bony or cartilaginous fragments in the joint cavity), which is clamped between the articular surfaces. In addition to the types of pain listed above, patients with osteoarthritis, when reactive synovitis occurs, may have pain (constant, pressing, aching) regardless of movement.

Periods of exacerbations alternate with remissions. Complications of osteoarthritis, such as synovitis, etc., are even more common with increased strain. The result of muscle pain is the formation of contractures in the muscles and the occurrence of spasm in the limb. Noises in the joint gradually take on a permanent character. Muscle cramps and muscle and joint discomfort occur at rest. Increasing deformity of the joint and severe pain causes lameness. In advanced stages of osteoarthritis, deformities are even more pronounced, the joint becomes crooked, and contractures occur due to severe deformities of bones and other structures of the limb. Patients find it difficult to stand, and patients suffering from osteoarthritis have to walk with a cane or crutches to get around. With hip arthritis, the inability to bend the hip makes it impossible for the patient to sit. Patients cannot walk up and down stairs with knee arthritis.

In the initial stage of osteoarthritis, examination of the patient shows no visible changes. The shape of the joint may be normal, and there may be slight swelling. On palpation, mild to moderate pain is possible. It can be said that movements are performed to the full extent. Later, the deformity becomes pronounced, and severe pain is detected on palpation. At this time, the patient readily shows pain points. At the edges of the articular cleft, there are noticeable thickenings. Motor activity is restricted, and the phenomenon of joint instability is detected. Distortions of the anatomical axis of the joint can be revealed. With reactive synovitis, the size of the joint becomes larger, the joint itself has a ball shape, and fluctuation is detected during palpation.

Diagnosis

Diagnosis is made on the basis of clinical symptoms and radiographs of arthritis. X-rays should always be taken in a standing position. X-rays of arthritis show articular cartilage and dystrophic changes in the bone tissue under the articular cartilage. The articular cleft is narrowed, the bone surface is deformed and thickened, and cyst-like masses, subchondral osteosclerosis, and osteophytes can be seen. In some clinical cases, unstable phenomena such as curvature of the anatomical axis of the limb and subluxations can be seen.

X-rays of coxarthrosis and gonarthrosis are presented

The severity of arthrosis based on clinical manifestations does not always correlate with the radiological signs of the disease. However, there are certain exceptions to the rules. Thus, osteophytes appear in the initial stage of the disease and are the first radiological sign of the disease. At the beginning of arthritis, the edges of articular surfaces become sharp; as the disease progresses, they become even more thickened and bony protrusions and spines gradually appear. The articular gap narrows later. At this time, the articular cleft may take a wedge shape due to the phenomenon of instability of the joint. At about the same time, osteosclerosis begins to develop in the bone surface below the cartilage; cyst-like tumors form in the bone tissue near the joint. Based on the radiological signs, the following degrees of arthrosis are distinguished (Kellgren-Lawrence classification):

First degree (suspected arthrosis) – possible narrowing of the articular cleft, no osteophytes or a small number of them.

Second degree (mild arthrosis) – possible narrowing of the articular cleft, osteophytes are clearly visible.

Third degree (moderate arthrosis) – there is some narrowing of the joint cleft, osteophytes are clearly visible, and bone deformities are possible.

Fourth degree (severe arthrosis) – serious narrowing of the joint cleft, bone deformities and osteosclerosis are clearly visible.

The picture shows the radiological stages of arthrosis

Sometimes the radiographs are not enough to properly assess the condition of the joint. Computed tomography (CT) scans are used to evaluate the bone structure, and magnetic resonance imaging (MRI) scans are used to evaluate the soft tissue. When secondary arthritis due to chronic inflammation is suspected, consultation with certain specialists – endocrinologist, hematologist, gynecologist, rheumatologist, etc. – is necessary.

Treatment

Conservative treatment methods

Non-steroidal anti-inflammatory drugs

At the initial stage of gonarthrosis, non-steroidal anti-inflammatory drugs are used to relieve symptoms, since inflammation takes part in its development along with mechanical factors.

Chondroprotectors

Currently, glucosamine and chondroitin sulfate are the most commonly used preparations for the treatment of gonarthrosis, which are taken orally by patients. These two substances are important components for the continued existence of normal articular cartilage. The therapeutic effects of these medications are visible after a few months. However, there is still controversy over the use of these drugs and no reliable evidence that they can change the course of the disease, but despite this, good treatment results can be obtained in some patients.

Intra-articular injections

The use of intra-articular injections of hyaluronic acid, help relieve pain in patients within 6-12 months. This method of treatment has no other side effects besides an allergic reaction. Hyaluronic acid is a substance that is part of articular cartilage. It helps the articular surfaces slide against each other and protects the cartilage cells. Pain relief is not the main purpose of injecting hyaluronic acid into the joint cavity. This procedure is performed in order to increase the amount of hyaluronic acid, to ensure the gliding of articular surfaces, and to increase the resistance of cartilage tissue. There are different preparations of hyaluronic acid. Methods of injection: for 6 months once a week (3 times); once every 6 months; once a year. Hyaluronic acid preparations obtained synthetically have a lower probability of developing allergies.

Intra-articular steroid injections immediately relieve symptoms, but their prolonged use may accelerate the progression of the disease. Corticosteroids are used for long-term treatment because of their analgesic and anti-inflammatory effects. Exposure time is short and repeated doses are not recommended, especially in the early stages of gonarthrosis. They are most commonly used in patients with severe gonarthrosis who do not want to undergo surgical intervention on the knee joint. Although they are effective analgesics, there is evidence in the literature that they cause irreversible damage to the articular cartilage. However, when used correctly, such cases do not occur. There is no need for local anesthesia prior to injection. These injections must be given under strictly sterile conditions, as otherwise infection may enter the joint cavity.

Physiotherapy

It is necessary to carry out physical therapy, exercises from therapeutic physical training to reduce the patient’s body weight. In fact, everyone and especially patients with gonarthrosis need physical therapy. By strengthening the muscles of the posterior and anterior surface of the thigh, it is possible to reduce the load and pressure that comes to the knee joint. At a minimum, this helps the gonarthrosis patient maintain a comfortable standing position, and reduces the rate at which arthritis develops. For arthritis of the other joints, similar exercises should also be done.

Surgical treatment

Despite the above treatment methods, especially with severe forms of arthritis, it is very difficult to treat with conservative methods, and in such cases, surgical methods of treatment are used.

Surgery to change the axis direction of the limb

This surgery is performed for moderately severe arthritis, on joints that are subjected to a high level of stress. The aim of the operation is to remove the load from the damaged area of the joint and direct it to the healthy part. To do this, the bone is cut and placed in the correct position, brought to the correct angle, and fixed with a metal plate or an external fixator. This procedure is usually performed on younger patients who are not recommended to have an endoprosthesis. After this surgery, patients are free of pain for 5-7 years.

Re-direction of the limb axis

The following illustration shows X-rays before and after limb axis re-direction surgery

Joint closure (arthrodesis)

In this surgery, the cartilage tissue that forms the joint is cut away and removed, and the bones are fixed to each other using various methods in an end-to-end fashion. After this surgery, the patient’s pain disappears, but no movement is possible in the operated joint. This operation is most often recommended for young patients who are engaged in strenuous physical labor.

Figure shows X-rays before and after joint closure surgery (arthrodesis)