What are the different joints in the human body?

Understanding the anatomy of our joints is crucial to pinpoint the pain's origin: from the bones themselves or other structures within them. Human joints aren't all the same. They're categorized into three types:

• Fixed: pelvis and skull. As the name suggests, these joints don't move;
• Semi-mobile: the spinal column. This joint comprises bones (vertebrae), cartilage-covered, and separated by small fibrocartilaginous discs. These discs act as "shock absorbers," providing spine elasticity and flexibility;
• Mobile: the most numerous, including hands, feet, shoulders, and legs. These consist of smooth bones within an articular capsule;

Joints can also be classified based on their constituent tissue:

• Fibrous joints: joined solely by fibrous tissue. These are hard, fixed joints lacking internal cavities;
• Cartilaginous joints: linked or covered with cartilage, also fixed or semi-mobile;
• Synovial joints: mobile joints with various structures (tendons, ligaments) enabling frictionless movement;

Joint pain: it's not just about rheumatism

Joint pain: a very common symptom

Pain in one or more joints is a common symptom in young people and even more frequent in older adults.

Many factors cause this pain, ranging from injuries to articular structures to chronic arthritis inflammation, including age-related rheumatism.

Osteoarthritis, for instance, is typical joint deterioration due to aging, causing often disabling pain. Musculoskeletal pain also characterizes infectious diseases like influenza, often presenting as "broken bones" feeling.

Which joints are involved in joint pain?

Pain can occur in any joint, including:

• The shoulder joint;
• The elbow joint;
• Hip joint (hip pain);
• The knee joint;
• Ankle joint;
• Small joints of the hands and feet;

Common accompanying abnormalities include stiffness, limited movement, swelling, redness, and bruising.

Musculoskeletal pain is categorized as chronic or temporary, treated differently based on the cause.

Joint pain: when the cause is osteoarthritis

Understanding what osteoarthritis is

Osteoarthritis is a major cause of joint and musculoskeletal pain. This bone disease is common with age, related to wear and tear of joint structures, especially cartilage.

Articular cartilage lines bone ends, protecting them from impact during movement. With age, this protective layer wears down, causing bones to rub against each other, resulting in pain.

What can be done in case of osteoarthritis?

Osteoarthritis is incurable. Cartilage wear is progressive and irreversible.

However, pain and loss of function can be alleviated through exercises, analgesics (if prescribed), and hyaluronic acid injections to restore mobility.

Weight loss (if obese) is crucial to prevent immobility. Surgery is a last resort.

Causes of joint pain: rheumatic diseases

Gout

A rheumatic disease linked to hyperuricemia (excess uric acid). Causes include high-meat diets, kidney dysfunction, metabolic disorders, medications, and family history. It affects men more than women, typically starting around age fifty.

Arthritis secondary to viral, bacterial or fungal infection

Joint inflammation caused by pathogens that travel through the bloodstream to the joints. Treatment involves antibiotics, antivirals, or antifungals.

Systemic lupus erythematosus

Lupus, like rheumatoid arthritis, is a chronic autoimmune inflammatory disease. It usually starts young and is managed with immunomodulatory or biological drugs. Women are more commonly affected.

Neurological rheumatism

Pain from neurological rheumatism stems not from joint inflammation, but from nerve inflammation within the joint. Causes include osteomyelitis and Raynaud's syndrome.

Atypical joint pain of fibromyalgia syndrome

Generalized musculoskeletal pain is the main symptom of fibromyalgia, an extra-articular rheumatic disease. While similar to arthritis in symptoms, fibromyalgia is different, lacking autoimmune or inflammatory origins and causing no internal damage. Even with severe pain and immobility, joints would appear healthy internally.

Diagnosing fibromyalgia is difficult, often taking years due to the overlapping symptoms.