🦴 Joint Health: Causes of Pain, Types of Disease and Ways to Maintain Mobility

Joints are the movable connections between bones that provide movement, shock absorption and support for the body. Healthy joints allow us to walk, run, bend, lift objects and perform thousands of movements every day without even thinking about it. However, with age, under excessive loads or as a result of disease, joint tissue wears down, and pain, stiffness and limited mobility appear. According to statistics, joint diseases are among the three most common causes of disability in the world: they affect more than 500 million people. Understanding how joints are built, the risk factors and the methods of prevention is the key to staying active and mobile throughout life.

Joint structure: how it works

A typical joint consists of several key elements, each of which performs its own function. Articular cartilage covers the surfaces of the bones that come into contact. It is a smooth, elastic tissue 2–5 mm thick that allows frictionless gliding and absorbs loads. Cartilage has no blood vessels of its own — it receives nourishment from the synovial fluid, which is why it repairs itself slowly and becomes thinner with age.

Synovial fluid is a clear, viscous fluid that fills the joint cavity. It acts as a lubricant, reducing friction between the cartilage surfaces, and at the same time serves as a nutrient medium for the cartilage tissue. The synovial membrane lines the joint from the inside and produces this fluid. The joint capsule is a dense connective tissue sheath surrounding the joint, which keeps it sealed and protects it mechanically.

Ligaments are strong bands of collagen fibres that connect bones and limit excessive movement of the joint, preventing dislocations. Menisci (in the knee joint) are crescent-shaped cartilage pads that provide additional shock absorption. Tendons attach muscles to bones and transmit muscular force, making movement possible.

Main joint diseases

Osteoarthritis (arthrosis) is the most common joint disease, affecting more than 300 million people worldwide. It is a degenerative process in which the articular cartilage gradually breaks down. As the cartilage thins, the bones begin to rub against each other, causing pain, inflammation and limited mobility. The knee and hip joints, the joints of the hands and the spine are affected most often. Risk factors: age (over 50), excess weight, joint injuries, heavy physical labour, genetic predisposition. An early sign is pain under load that goes away at rest; later the pain becomes constant, and crunching, deformity and significant restriction of movement appear.

Rheumatoid arthritis is a systemic autoimmune disease in which the immune system mistakenly attacks the body's own joint tissues. It mainly affects the small joints of the hands and feet, but large joints can also be involved. The damage is characteristically symmetrical (both wrists, both hands). The disease shows itself through morning stiffness (lasting more than 30 minutes), swelling, tender joints and their gradual deformity. Women are affected more often, and the peak incidence is at 40–60 years of age.

Gout is a disease related to a disorder of uric acid metabolism: its crystals (urates) are deposited in the joints, causing acute attacks of excruciating pain. A classic attack begins suddenly, usually at night, with severe pain, redness and swelling in the joint of the big toe. Risk factors: excessive consumption of meat, offal and beer, obesity, genetic predisposition. Men are affected much more often.

Bursitis is inflammation of a synovial sac (bursa) located near a joint. Bursae cushion friction between bones, tendons and muscles. Bursitis causes localised pain, swelling and restricted movement. The shoulder, elbow and knee joints are affected most often. Causes: chronic overload, injuries, infections.

Risk factors by age group

At a young age (20–35 years), joint problems are more often linked to injuries (sports or work-related), excessive loads and hereditary diseases. A torn meniscus, damage to the cruciate ligaments of the knee and dislocations are frequent reasons for seeing an orthopaedist.

In middle age (35–50 years), the consequences of accumulated cartilage wear begin to appear. Excess weight, sedentary work and a lack of physical activity speed up degenerative changes. This is the period when the initial signs of osteoarthritis (crunching, discomfort under load) should become a signal to take action.

In older age (50+ years), osteoarthritis becomes the dominant problem. Cartilage degeneration is joined by osteoporosis (reduced bone density), sarcopenia (loss of muscle mass) and worsening coordination — all of which increase the risk of falls and fractures. Rheumatoid arthritis and gout may flare up or appear for the first time.

The impact of weight and physical activity

Excess weight is one of the main enemies of the joints. Every extra kilogram places an additional load of 4 kg on the knee joint when walking and 7 kg when climbing stairs. In people with obesity, the risk of developing knee osteoarthritis is 4–5 times higher. Losing 5 kg reduces the risk of symptomatic knee osteoarthritis by 50%. Apart from the mechanical load, fat tissue produces inflammatory substances (adipokines) that accelerate the breakdown of cartilage.

Physical activity is critically important for joint health, but its type matters. Moderate regular exercise strengthens the muscles around the joints (the muscular corset), improves cartilage nutrition (cartilage is nourished through cyclic compression and release), and helps maintain a normal weight and flexibility. Beneficial: swimming (takes the load off the joints), walking, cycling, yoga, Pilates, light gymnastics. Dangerous: running on asphalt when overweight, jumping, deep squats with heavy weights, contact sports with a high risk of injury.

Nutrition for joint health

Proper nutrition supplies the joints with building materials and protects them from chronic inflammation. Collagen is the main protein of cartilage. Its sources: bone broths, meat jelly (aspic), gelatine, sea fish. With age, the body's own collagen production declines, so getting it from outside becomes especially important.

Glucosamine and chondroitin are components of cartilage tissue. Glucosamine stimulates the production of proteoglycans — molecules that hold water in cartilage and give it its elasticity. Chondroitin prevents the breakdown of cartilage and helps retain moisture. Their natural sources are cartilage and the shells of marine crustaceans; they are often used in the form of supplements.

Omega-3 fatty acids (oily sea fish, flaxseed oil, walnuts) have a powerful anti-inflammatory effect. Studies show that regular intake of omega-3 reduces the intensity of pain and morning stiffness in rheumatoid arthritis. Vitamin D is necessary for calcium absorption and bone health; its deficiency is linked to faster cartilage degeneration. Sources: sunlight, oily fish, egg yolk; in middle and northern latitudes, supplementation is recommended. Vitamin C is involved in collagen synthesis, and sulphur (found in garlic, onions and cruciferous vegetables) is necessary for the formation of the cartilage matrix.

Foods that increase inflammation should be limited: sugar and refined carbohydrates, trans fats, too much red meat, alcohol. With gout, purines must be strictly limited (offal, meat broths, some types of fish, legumes, beer).

Workplace ergonomics and injury prevention

For office workers, a properly organised workplace is important: a chair with lumbar support, feet on the floor or on a footrest (knees at a 90° angle), the monitor at eye level. Every 45–60 minutes you need to get up, stretch and do a few simple exercises for the neck, shoulders and lower back. When working at a computer, an ergonomic mouse and keyboard help reduce the load on the joints of the hands.

To prevent sports injuries, a proper warm-up before training (at least 10 minutes), a gradual increase in loads, and the use of the right footwear and protective equipment are essential. When lifting heavy objects, keep your back straight and lift with your legs, not your lower back. On slippery surfaces, wear shoes with non-slip soles.

Morning stiffness: what it means

Morning joint stiffness — a feeling of tightness and of being "rusty" after waking up — is an important diagnostic sign. In osteoarthritis, stiffness usually lasts 10–15 minutes and quickly passes once you start moving. In rheumatoid arthritis, stiffness is much more pronounced and lasts more than 30 minutes, sometimes up to several hours. This difference helps the doctor distinguish between degenerative and inflammatory joint damage. If morning stiffness has become regular and prolonged, it is a reason to get examined.

When joint replacement is considered

Joint replacement (replacing a joint with an artificial one) is considered when conservative treatment has been exhausted: the cartilage is almost completely destroyed, the pain is constant and is not relieved by usual means, mobility is severely limited, and quality of life is significantly reduced. Hip and knee replacements are performed most often. Modern joint implants last 15–25 years and make it possible to return to an active life. However, surgery is a last resort, and every effort should be made to preserve your own joint for as long as possible.

Myths about joint diseases

"Cracking joints are a sign of disease" — not necessarily: painless cracking without swelling or restricted movement is most often harmless and is related to the movement of gas bubbles in the synovial fluid. "You shouldn't exercise if you have bad joints" — on the contrary, properly chosen physical activity is essential; immobility speeds up the breakdown of cartilage. "Osteoarthritis and arthritis are the same thing" — no: osteoarthritis is the degenerative breakdown of cartilage, while arthritis is an inflammatory process; their causes, course and treatment differ. "Glucosamine helps everyone" — the effectiveness of supplements varies from person to person; they may help in the early stages but will not restore completely destroyed cartilage. "Cold weather causes arthritis" — cold can make symptoms worse (due to narrowing of blood vessels and increased viscosity of the synovial fluid), but it is not the cause of the disease.

Joint health is the result of daily habits: maintaining a normal weight, regular moderate physical activity, proper nutrition, and avoiding injuries and getting chilled. Even if problems have already appeared, a sound approach to treatment and rehabilitation can significantly improve quality of life and preserve mobility.