The Science of Osteoarthritis

Osteoarthritis is the most common type of arthritis in the UK, where it affects around 8.75 million people. It causes joints to become painful and stiff, which can lead to less mobility and chronic pain. But what actually is osteoarthritis, how does it work and what can you do to manage your symptoms?

“Arthritis is a broad term referring to inflammation and degeneration of the joints, causing pain, swelling, and decreased mobility,” says Dr. Rosmy Barrios, MD, a medical advisor for the Health Reporter. “There are various forms of it, with osteoarthritis being the most prevalent.” Other forms of arthritis include rheumatoid arthritis, gout, psoriatic arthritis and ankylosing spondylitis. Each type has different causes and symptoms, but they all involve inflammation and damage to the joints.”

Osteoarthritis is the most common type of arthritis. It occurs when the cartilage that cushions the ends of bones in the joints gradually wears down. When cartilage wears down, bone rubs on bone, causing pain, swelling, stiffness and decreased mobility.

Osteoarthritis can affect any joint in the body, but it most commonly affects the knees, hips, hands, fingers, shoulders and spine.

“Cartilage is the smooth, flexible, and rubbery tissue that covers the ends of bones in joints, providing a low-friction surface and acting as a shock absorber during movement,” says Dr. Rosmy Barrios. “It becomes damaged due to several key causes. For example, injuries or repetitive stress on the joints can lead to the breakdown of cartilage, causing it to become rough and thin.”

The exact cause of osteoarthritis is not fully understood, but several factors are thought to increase the risk of developing osteoarthritis, such as:

• Age: The risk of osteoarthritis increases as you get older, as the cartilage becomes thinner and less resilient over time.

• Gender: Whilst osteoarthritis affects both men and women, it is more likely to develop in women.

• Genetics: Osteoarthritis may run in families, although no single gene has been identified as responsible.

• Injury: Overusing or injuring a joint can accelerate the wear and tear of cartilage. This can happen as a result of sports, accidents or repetitive movements.

• Weak muscles: If your muscles don’t adequately support the joints, it can result in poor alignment and lead to too much pressure on certain joints.

• Obesity: Being overweight or obese puts extra strain on the joints, especially those that bear most of your weight, such as your knees and hips.

• Other conditions: Some conditions can damage the joints or cartilage directly or indirectly, such as rheumatoid arthritis, gout, diabetes or infections.

Damaged cartilage leads to osteoarthritis by causing changes in the whole joint structure and function. These changes include:

• Loss of cartilage: As cartilage wears away, the bones lose their smooth surface and become rough and irregular. This increases friction and reduces shock absorption in the joint.

• Bone growths: The body tries to repair the damage by producing more bone at the edges of the joint. These bony growths are called osteophytes or spurs. They can change the shape of the joint and limit its movement.

• Inflammation: The damaged joint triggers an inflammatory response in the body. This causes swelling, redness, warmth and pain in the joint. Inflammation can also damage other tissues in the joint, such as ligaments and tendons.

• Muscle weakness: The pain and stiffness in the joint can make it difficult to use or move it normally. This can lead to muscle weakness and wasting around the joint. This can further reduce stability and mobility in the joint.

“The terms ‘wear and tear’ and ‘degenerative joint disease’ are often used interchangeably with osteoarthritis,” says Dr. Rosmy Barrios. “Wear and tear imply that the condition is caused by the natural ageing process and the stresses placed on the joints over time. Degenerative joint disease refers to the gradual deterioration of the joint structures, including cartilage, ligaments, and bone.”

The term ‘wear and tear’ implies that osteoarthritis is an inevitable consequence of ageing or using your joints over time. However, this is not necessarily the case and can be misleading.

Osteoarthritis is not simply a result of wear and tear or degeneration. It is a complex condition that involves many factors that affect how your joints function and respond to damage.

“Osteoarthritis is not reversible, but it can be managed effectively to improve the quality of life for affected individuals,” says Dr. Rosmy Barrios. “Treatment focuses on reducing pain, improving joint function, and slowing the progression of the disease. The key signs and symptoms of it include joint pain, stiffness, and swelling - but they can vary in intensity and may worsen over time.”

There are many treatments available to help relieve pain while improving function and quality of life for people with osteoarthritis. These include:

• Lifestyle changes: Maintaining a healthy weight, exercising regularly, avoiding joint injury and using assistive devices can help reduce strain and stress on the joints and improve muscle strength and joint stability.

• Medication: Painkillers, anti-inflammatory drugs and topical creams can help ease pain and inflammation in the joints. Some medications can also slow down the progression of osteoarthritis by protecting the cartilage or modifying the immune system.

• Supportive therapies: Physiotherapy, occupational therapy, podiatry and acupuncture can provide advice, exercises, devices and techniques to help with joint mobility, posture, balance and daily activities.

• Surgery: In some cases, where other treatments have not been effective or the joint damage is severe, surgery may be considered to repair, strengthen or replace the damaged joint. This can improve pain, function and appearance of the joint.

The main signs and symptoms of osteoarthritis are:

• Joint pain: The pain may be dull, aching or sharp, and may vary in intensity.

• Joint stiffness: The joint may feel stiff or tight, especially after waking up or being inactive for a while. The stiffness usually lasts less than 30 minutes and may improve with movement.

• Joint swelling: The joint may look swollen or enlarged due to inflammation or bony growths. The swelling may be soft or hard, and may feel warm or tender to touch.

• Joint problems: The joint may have reduced range of motion, difficulty bending or straightening, clicking or grating sounds, or locking or giving way.

• Inflammation around the affected joint.

The severity and frequency of these symptoms can vary from person to person and from joint to joint. Some people may have mild or occasional symptoms, while others may have more severe or constant problems that affect their daily life.

To diagnose osteoarthritis, your doctor will ask you about your symptoms and examine your joints. They will look for signs of joint damage, such as swelling, tenderness, bony growths or reduced movement.

Your doctor may also ask you about your medical history, your family history of arthritis, your lifestyle and any medications you are taking.

In most cases, no further tests are needed to confirm the diagnosis of osteoarthritis. However, to rule out other possible causes of your joint problems, your doctor may sometimes order tests such as:

• Blood tests: To check for signs of inflammation or infection in your body, or to detect other types of arthritis, such as rheumatoid arthritis or gout.

• X-rays: To show the extent of cartilage loss, bone damage or bony growths in your joints.

• MRI scans: To provide more detailed images of your joints and surrounding tissues, such as ligaments, tendons and muscles.

“The key stages of treatment for osteoarthritis involve a multi-faceted approach,” Dr. Rosmy Barrios says. “Initially, non-pharmacological interventions are recommended, such as weight management, exercise, physical therapy, and the use of assistive devices. OTC pain relievers and anti-inflammatory medications may also be used to manage pain. In severe cases where conservative treatments are ineffective, surgical interventions like joint replacement may be considered. Overall, the goal of treatment is to improve joint function, alleviate pain, and enhance the patient's overall well-being.”

The treatment for osteoarthritis depends on the severity of your symptoms, the joints affected and your personal preferences. There is no one-size-fits-all approach to treating osteoarthritis. However, there are some general stages of treatment that can be followed:

• Stage 1: Self-care. This involves making lifestyle changes that can help prevent or reduce joint damage and pain. These include losing weight if you are overweight or obese, exercising regularly to strengthen your muscles and joints, avoiding activities that worsen your symptoms, using assistive devices such as braces or walking aids if needed, applying heat or cold packs to ease pain and swelling, and taking over-the-counter painkillers such as paracetamol or ibuprofen if necessary.

• Stage 2: Supportive care. This involves seeking professional help from health care providers who can offer advice, support and therapies to help you manage your condition. These include physiotherapists who can teach you exercises to improve your joint mobility and function; occupational therapists who can suggest ways to adapt your home and work environment to make daily tasks easier; podiatrists who can provide foot care and orthotics to improve your posture and balance; acupuncturists who can use needles to stimulate specific points on your body to relieve pain; and counsellors who can help you cope with the emotional impact of living with osteoarthritis.

• Stage 3: Medication. This involves taking prescription drugs that can help control pain and inflammation in your joints. These include non-steroidal anti-inflammatory drugs (NSAIDs) such as naproxen or diclofenac; corticosteroids such as prednisolone; disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate; biologic drugs such as etanercept; or opioids such as codeine or tramadol. These drugs have different mechanisms of action, benefits and risks. Your doctor will discuss with you the best option for you based on your condition and medical history

• Stage 4: Surgery. This involves undergoing a surgical procedure to repair, strengthen or replace the damaged joint. This can improve pain, function and appearance of the joint. There are different types of surgery for osteoarthritis, such as arthroplasty, arthrodesis or osteotomy. The type of surgery depends on the joint affected, the extent of damage and your overall health. Surgery is usually considered as a last resort when other treatments have failed or are not suitable.

• Stage 5: Advanced care. This involves managing the end-stage complications of osteoarthritis, such as severe pain, disability, infection or bleeding in the joint. This may require hospitalisation, intensive care or palliative care. The aim of advanced care is to provide comfort, dignity and quality of life for people with severe osteoarthritis.
  
  

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