Osteoarthritis

Osteoarthritis is the most common form of arthritis and the leading cause of chronic disability in the United States. According to epidemiological data, the disease affects approximately 30 to 53 million people in the United States, while globally it causes moderate to severe disability in 43.4 million individuals. It is estimated that 40% of the population will express osteoarthritis in their life.

Osteoarthritis is a degenerative joint disease that affects nearly 40% of the population and accounts for approximately 25% of visits to primary care physicians. It is also noteworthy that 80% of the population shows radiographic evidence of osteoarthritis after the age of 65, although only about 60% of these individuals experience symptoms. Osteoarthritis is commonly referred to by patients as “wear-and-tear arthritis.”

The symptoms of osteoarthritis develop gradually and worsen over time. Early recognition of these symptoms is a key factor in the effective management of the condition. Osteoarthritis of the knee and hip is the most common form of the disease and represents the leading cause of pain and reduced mobility in individuals over the age of 50.

Pain is the primary symptom of osteoarthritis and is usually felt during movement of the affected joint. Initially, it appears after intense physical activity, but gradually it becomes more frequent and may even occur at rest. When pain occurs during the night and awakens the patient, it typically indicates advanced osteoarthritis.

Stiffness is also a characteristic symptom and is most noticeable in the morning or after prolonged periods of inactivity. It usually lasts less than 30 minutes and improves with movement. In the early stages, patients often report noticeable relief after a few minutes of walking.

As the cartilage wears down, the bones within the joint rub against each other, producing characteristic grinding or crackling sounds (crepitus) during movement. These sounds are often accompanied by a sensation of friction and are gradually followed by a reduction in the joint’s range of motion. In advanced stages, patients experience difficulty performing simple daily activities, such as climbing stairs or walking short distances.

Swelling is a common finding, particularly in weight-bearing joints. The synovial membrane becomes inflamed and produces an increased amount of synovial fluid, leading to fluid accumulation within the joint. In the knee, this condition is commonly referred to as “water on the knee” or joint effusion (hydroarthrosis). Under normal conditions, a joint contains approximately 7–10 cc of synovial fluid. However, in osteoarthritis, this amount increases significantly, causing pain, stiffness, and a sensation of warmth in the affected area.

Osteoarthritis is a multifactorial condition that is not caused by a single factor, but rather by complex interactions among biological, mechanical, and environmental parameters. It is primarily classified into primary and secondary types, each with distinct characteristics and underlying causes.

Primary osteoarthritis is a chronic degenerative disorder associated with aging, although it is not caused exclusively by it. It is often observed that some individuals, even in their nineties, do not exhibit clinical or functional signs of the disease. As a person ages, the water content of the cartilage decreases due to reduced proteoglycan levels, making the cartilage less elastic. Without the protective effects of proteoglycans, collagen fibers become more susceptible to degradation, thereby accelerating the degenerative process.

Secondary osteoarthritis is caused by other contributing factors, although the resulting pathology is similar to that of primary osteoarthritis. In clinical practice, it frequently occurs in cases associated with:

• Joint or ligament injuries
• Congenital joint disorders
• Metabolic diseases such as diabetes
• Inflammatory conditions (rheumatoid arthritis, gout)
• Obesity and increased body weight

It is worth noting that secondary osteoarthritis tends to appear at a significantly younger age compared to primary osteoarthritis.

Genetic predisposition plays a decisive role in the development of osteoarthritis. Several studies have demonstrated a higher prevalence of the disease among siblings, particularly among monozygotic (identical) twins. Remarkably, up to 60% of osteoarthritis cases are believed to be influenced by genetic factors.

At the same time, metabolic factors significantly contribute to the development of the disease. In women after menopause, the abrupt decline in estrogen levels negatively affects cartilage structure. In addition, adipose tissue functions as an inflammatory organ, further aggravating the condition. This helps explain the association between obesity and osteoarthritis beyond the simple mechanical stress imposed on the joints.

Initially, the diagnosis of osteoarthritis is based on obtaining a detailed medical history and conducting a thorough clinical examination. During the clinical assessment, joint tenderness, flexibility, and overall functionality are carefully evaluated. Particular attention is given to the joint’s ability to perform specific movements. The patient’s medical history is equally important, as it reveals the pattern of pain—typically mechanical in nature, meaning that it worsens with movement and improves with rest.

In addition, X-rays are the most important imaging tool for confirming the diagnosis, although they are not always required. The characteristic radiographic findings include:

• Narrowing of the joint space (reduced space between the bones)
• Presence of osteophytes (bony projections) at the joint margins
• Subchondral bone sclerosis
• Subchondral cysts

However, a critical point that is often overlooked is that radiographic findings do not always correlate with the clinical picture. In practice, patients may present with severe pain but relatively minor joint damage on imaging, while others with significant radiographic degeneration may report minimal symptoms. The Kellgren–Lawrence grading system, ranging from stage 0 (normal) to stage 4 (complete loss of joint space), is commonly used to classify the severity of osteoarthritis.

Finally, distinguishing osteoarthritis from rheumatoid arthritis is of fundamental importance. Although the two conditions may appear similar at first glance, they are entirely different diseases. Osteoarthritis is a degenerative condition associated with aging, whereas rheumatoid arthritis is an autoimmune disorder with a genetic basis.

An orthopedic surgeon with extensive clinical experience manages osteoarthritis through a combined approach tailored to the severity of the condition and the individual needs of each patient. With modern technology and the capabilities of robotic-assisted surgery, we are now able to replace part or the entire joint that has been severely damaged, thereby fully restoring the patient’s mobility.

Weight loss is a cornerstone of treatment. For every kilogram lost, the mechanical load on the knee is reduced by approximately four kilograms. In addition, adipose tissue produces cytokines that promote inflammation. Therefore, even a modest reduction in body weight can decrease the risk of developing osteoarthritis by up to half.

Physiotherapy aims to reduce pain and restore mobility. Patients are typically advised to follow an exercise program 3–5 times per week, lasting 30–45 minutes per session, which includes:

• Aerobic exercises (walking, swimming)
• Resistance exercises to strengthen the quadriceps and gluteal muscles
• Isometric exercises to improve joint stability

Pharmacological management usually begins with acetaminophen (500–1,000 mg every 6–8 hours, with a maximum daily dose of 4 g). In cases of significant inflammation, nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and diclofenac, may be prescribed, always with careful consideration of potential gastrointestinal side effects. Topical preparations, such as diclofenac gels, provide targeted pain relief at the affected site.

When conservative treatment fails, surgical intervention is recommended. Arthroscopy may be indicated for joint debridement and removal of loose bodies. In more advanced cases, total or partial joint arthroplasty—often performed with robotic-assisted technology—is used to replace the damaged joint surfaces with prosthetic implants. Ideally, minimally invasive techniques are applied, allowing for rapid mobilization and hospital discharge within 2–3 days.

In summary, osteoarthritis is a complex condition that affects millions of people worldwide, significantly reducing their quality of life. Early diagnosis plays a decisive role in effective management. Moreover, an individualized therapeutic approach is essential, as each patient presents with different symptoms and needs.

The symptoms of osteoarthritis—such as pain, stiffness, swelling, and restricted movement—progress gradually and require systematic monitoring. However, it is important to emphasize that the disease can be effectively managed with the appropriate combination of therapeutic strategies.

Lifestyle modifications are of primary importance in treatment, including weight loss and regular exercise. At the same time, pharmacological therapy and physiotherapy interventions provide substantial relief. In cases of advanced disease, surgical options such as arthroscopy and joint arthroplasty can restore joint function.

Undoubtedly, the comprehensive management of osteoarthritis requires close collaboration between the physician and patient. Through this partnership, not only is symptom reduction achieved, but also the best possible functional outcome and quality of life for patients.