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Osteoarthritis

Osteoarthritis, also known as degenerative joint disease or simply arthritis, is a common joint disorder that affects millions of people worldwide. It is a chronic condition that can cause significant pain, stiffness, and functional limitations in the joints, particularly in the elderly. Although it is often considered a natural part of aging, osteoarthritis can have a significant impact on an individual's quality of life and daily functioning. The most commonly affected joints include the hips, knees, hands, and spine. Osteoarthritis should not be confused with arthritis. Arthritis is an umbrella term under which osteoarthritis can be classified.

Causes

For a long time, osteoarthritis was thought to simply be the result of wear and tear on the joint cartilage, a consequence of aging. The common consensus was that prolonged excessive loading leads to the destruction of cartilage structures and inflammation. This, in turn, results in swelling, reduced range of motion, stiffness, and pain in the joint or joints. While the symptoms remain largely the same for those suffering from osteoarthritis, nowadays we know that osteoarthritis is a much more complex phenomenon and involves many more factors than just the degeneration of cartilage structures. New factors that must be taken into account include metabolic and inflammatory factors.

Joint cartilage is located at the ends of bones, so the bones are not in contact with each other when we move our joints. Cartilage thus reduces friction and participates in force transmission. Cartilage lacks vascularization, so it also heals very slowly, if at all. Although the most visible changes in osteoarthritis concern cartilage, osteoarthritis affects the entire joint and its structures. (1,2)

While it is not yet fully clear what factors are involved in the development of osteoarthritis, we know that inflammation of the synovium and systemic inflammatory reactions are involved. One explanatory model is that as cartilage degenerates, it sets off a chain reaction in various cells, resulting in the secretion of more inflammatory mediators that cause further damage to cartilage structures.

Systemic inflammation (e.g., low-grade inflammation) is also thought to be related to the development of osteoarthritis. In 2010, Yusuf et al. found that overweight is a clear risk factor for the development of osteoarthritis in the fingers. This leads to the idea that overweight is unlikely to be a risk factor simply because it increases joint load biomechanically.

Risk factors

Osteoarthritis can be broadly classified into two different groups: primary osteoarthritis, where the cause is unknown, and secondary osteoarthritis, which can result from conditions or injuries.

Age

Age is the greatest single risk factor. Globally, it is estimated that about 10 percent of men and 18 percent of women over 60 years old have symptoms of osteoarthritis.

Overweight / Metabolic Syndrome

Metabolic syndrome and overweight are clear risk factors for osteoarthritis. It also appears that type 2 diabetes and dyslipidemia (disorders of fat metabolism) are independent risk factors. Genetics also play a role, with studies identifying over 80 genes associated with the development of osteoarthritis.

Gender

Osteoarthritis is more common in men under 50 years old, while it is more common in women over 50 years old. Interestingly, individuals with low levels of vitamin C or vitamin D may have a higher risk of developing osteoarthritis. The effect of vitamin C on the treatment and prevention of osteoarthritis has been studied, with some studies showing positive results while others do not. More research is needed on this topic before any definitive conclusions can be drawn. (6)

Previous Injuries

It is well known that various injuries that damage the joint or joints can contribute to the development of osteoarthritis. This is referred to as post-traumatic osteoarthritis. Brown et al. estimated in 2006 that 12% of all cases of osteoarthritis could be post-traumatic.

Occupational Strain

According to studies, physically demanding work appears to be a risk factor for osteoarthritis. However, more research is needed on this topic.

Osteoarthritis symptoms

Usually, the most obvious and disruptive symptom of osteoarthritis is pain, and as mentioned earlier, the most commonly affected joints are the hip and knee joints, finger joints, and spine. Osteoarthritis can also occur in the ankle, wrist, elbow, and shoulder joints, but these are less common. In the early stages, pain typically occurs during certain activities, such as sports. Pain may not initially manifest in everyday activities. This can also lead to delayed diagnosis, as osteoarthritis may not be suspected. Over time, pain becomes more frequent and typically affects daily activities. Eventually, the pain may become constant, leading to avoidance of certain movements. Night pain is also not uncommon. In addition to pain, the joint often exhibits limitations in movement, swelling, locking, and crepitus (a crackling sound). The joint may also feel unstable, and stiffness is often present in the mornings, which improves within about 30 minutes. For example, in rheumatoid arthritis, morning stiffness of the joint or joints typically lasts longer than 30 minutes.

Interestingly, the extent of cartilage degeneration does not necessarily correlate with the level of pain in the joint. It is possible for a person with minimal visible cartilage damage on imaging to experience significant pain, while another person may have a joint that appears quite "unwell" on examination and yet experience no pain. (1)

Typical symptoms of osteoarthritis include:

Pain (often sharp/stabbing, but can also be constant and dull)
Reduced range of motion
Symptoms triggered by a physical activity, e.g., running or jumping. Pain often worsens throughout the day.
Joint stiffness and swelling
Night pain

How can osteoarthritis be diagnosed?

If osteoarthritis has been present for a long time, for example, for years, the symptoms are usually quite clear during the consultation. The patient should always undergo at least an examination of the range of motion of the affected joint, palpation (manual examination of the joint), and assessment for any visible swelling. An interview is also a crucial part of the examination. For the knee joint, the alignment and biomechanics of the knees may also be assessed, whereas in hip osteoarthritis, a typical finding, in addition to pain, is a restriction in internal rotation of the hip.

Imaging can also be useful to rule out other possible causes of pain. X-rays are often sufficient, but sometimes magnetic resonance imaging (MRI) or computed tomography (CT) may be used. Common findings in imaging studies include osteophytes (bone spurs), narrowing of the joint space, cysts, and subchondral sclerosis. Laboratory test results are usually normal in cases of osteoarthritis. (1)

Treatment

Currently, there is no curative treatment for osteoarthritis, but this does not mean that patients cannot find relief from their symptoms. In this case, relief means pain relief and improvement in movement or movements. Treatment options include therapeutic exercise, lifestyle modifications, manual therapy (massage, acupuncture, etc.), injections, and surgery.

Weight loss is one of the most significant factors that can be influenced. In several studies, it has been found that even a 10% weight loss significantly reduces the load on the knee joints. Significant benefits in pain reduction have also been observed with a weight loss of just 5 kilograms. (1)

Exercise! Sometimes patients come to the clinic being told that they should no longer engage in sports after an osteoarthritis diagnosis. This is a completely incorrect approach nowadays, even in light of research findings. There is good research data on the benefits of strength training and many other forms of exercise in alleviating osteoarthritis symptoms. Based on personal experience, the vast majority of osteoarthritis patients benefit from suitable exercise. Manual therapy, such as massage and joint mobilization, may provide relief from pain for some patients, but there is not strong research evidence for this.

Regarding medication, treatment often starts with acetaminophen (paracetamol), and if additional efficacy is needed, nonsteroidal anti-inflammatory drugs (NSAIDs) may be used. However, it is important to consider factors such as stomach and intestinal health. If medication does not provide the desired relief, the doctor may prescribe stronger medications such as opioids. However, opioids can cause side effects such as dizziness, nausea, and dependence. For example, in knee osteoarthritis, various injection therapies, such as hyaluronic acid or corticosteroids, are sometimes used. These may provide relief for some patients, but more research is needed.

Surgical treatment is the last resort if osteoarthritis symptoms worsen and the patient does not find relief from the aforementioned methods. In this case, joint replacement surgery is considered. After successful joint replacement surgery, the joint is usually pain-free or nearly pain-free.

Prognosis

Osteoarthritis is a progressive disease for which there is currently no curative treatment. The progression of the disease is highly individual. The disease often progresses more quickly in overweight individuals and the elderly. However, it is essential to remember that many people suffering from osteoarthritis can receive a great deal of help, including appropriate exercise, and their pain may even disappear completely for long periods.