Types of Arthritis
Arthritis has several classifications.
By the number of joints involved, the disease is divided into monoarthritis and polyarthritis (this diagnosis is usually made when 5 or more joints are affected).
By the form of its course, arthritis is divided into:
- acute (starts quickly and unexpectedly, most often linked to an infectious agent in the body);
- subacute (an intermediate stage between the acute and chronic forms, in which symptoms become less pronounced);
- chronic (has a wave-like course, with periods of flare-ups alternating with a complete absence of symptoms).
The process may also be divided into 4 stages depending on the severity of inflammation (1 is the mildest, 4 means severe irreversible changes, most often with complete immobility of the joint).
By location, the condition is divided into arthritis of the shoulder, elbow, hip, knee, ankle and finger joints.
Depending on the etiology (cause), arthritis can be:
1. Infectious:
- rheumatic;
- reactive;
- ankylosing spondyloarthritis (Bekhterev's disease);
- septic (acute purulent arthritis develops in the setting of sepsis);
- tuberculous, and others.
2. Traumatic (may occur after closed joint injuries or wounds, repeated minor trauma, and sometimes as a result of neglected rheumatoid arthritis).
3. Dystrophic:
- deforming osteoarthritis;
- occupational (or benign);
- endocrine;
- metabolic;
- aseptic subchondral necrosis.
4. Associated with other diseases, including autoimmune conditions (psoriatic, rheumatoid, gouty arthritis and others).
The classification is often simplified into inflammatory, degenerative (osteoarthritis) and traumatic arthritis.
In children and adolescents, doctors distinguish the juvenile form (in patients under 16, most often an autoimmune disease diagnosed when inflammation lasts more than 6 weeks) and idiopathic arthritis (its causes are also unknown; the main difference is widespread foci of inflammation that affect the whole body and can slow the child's growth and development). The idiopathic form is difficult to treat and therefore often leads to severe disability.
Deforming arthritis can also develop in the course of any type of the disease; it is characterized by bulky overgrowth of connective tissue, as well as deformity and impaired mobility of the joint.