What is osteoarthritis?
Osteoarthritis, also known as degenerative joint disease or the wear and tear arthritis, is the most common type of arthritis affecting people. It is characterized by the loss of cartilage associated with a periarticular bone response in the form of new bone formation subchondral bone thickening. Osteoarthritis can affect any joint in your body, but it most commonly affects knee, hip, lower back and neck, and the small joints of fingers. Osteoarthritis is known to be the most common cause of disability in the western world in the older adults.
A joint is where two bones meet. In a normal joint, the ends of the two bones are covered with a firm, rubbery material known as the cartilage. The cartilage basically acts as a cushion and allows the smooth movement of the two bones in the joint. In osteoarthritis, this cartilage breaks down. Therefore the cushion effect allowing the smooth movement of the two bones in the joint is lost and thus causing pain, swelling and difficulty in the movement of the joint. With time, the disease gets worse causing break down of the bone and therefore new bone starts to form which is known as spurs. In addition an inflammatory response is also triggered causing further damage to the joint.
What are the signs and symptoms of osteoarthritis?
The signs and symptoms of osteoarthritis may vary from one person to another depending on the joint involved and the severity of the disease. However, some of the most common features of osteoarthritis include:
- Pain – The cardinal feature of osteoarthritis is pain around the involved joint. The pain usually begins insidiously as an intermittent, deep ache which is often aggravated by movement of the joint and relieved on resting. Involvement of the knee joint is typically associated with pain on ascending or descending the stairs, squatting, climbing into buses, etc. Involvement of the hip joint may cause problems in one’s gait.
- Joint stiffness – Morning stiffness on waking up in the morning is often seen in osteoarthritis. This is usually short lived, lasting for about 5 to 30 minutes. Stiffness of the joints may also be noticed after periods of rest and this is termed as gelling of the joints and usually lasts for a few minutes.
- Swelling of the joint
- Functional limitation – Pain, swelling and stiffness of the affected joint may reduce the mobility of the joint.
- Crepitation – Crepitation is the sensation of the bones rubbing against each other during movements.
- Muscle weakness and muscle wasting – This may be noticed if the affected joint is not mobilized for a long period of time. This is often seen in patients who try to avoid using the affected joint due to the pain.
Who is at risk of developing osteoarthritis?
Although osteoarthritis can affect people of any gender and age, it is more common among the females over 55 years of age than men of the same age. The common risk factors for osteoarthritis include:
- Increasing age
- Obesity – Being overweight adds more strain on the joints especially the hip and knee joints. Many years of supporting the extra pounds of fat damages the cartilage that acts as a cushion and hastens the break down process thus increasing the risk of osteoarthritis.
- Family history of osteoarthritis
- Those involved in sports – The repetitive use of the joint may cause a high incidence of lower limb osteoarthritis. Athletes are more prone to injuries and this may accelerate the process of breakdown of cartilage.
- History of trauma such as a fracture through any joint – Trauma to the joints may speed up the process of breakdown of cartilage thus increasing the risk of osteoarthritis.
- Hypermobility of the joint – Increased range of joint movement and reduced stability may lead to osteoarthritis.
- Weak thigh muscles.
How is osteoarthritis diagnosed?
On your first visit to the doctor, your doctor will take a complete history and do a full physical examination on you to find out what the problem is. A diagnosis of osteoarthritis will be suspected if you show the signs and symptoms of osteoarthritis as mentioned earlier in this article.
Next, your doctor will order some investigations that will allow him/her to make an accurate diagnosis. Blood tests are often not useful in making a diagnosis of osteoarthritis. The following investigations will help to make a diagnosis:
- X-ray of the affected joint – This will show damage and other changes related to osteoarthritis.
- Magnetic Resonance Imaging (MRI) – Although it is expensive than an X-ray, it provides better imaging of the joint and help to detect osteoarthritis.
- Aspiration of the joint fluid – The doctor will numb the area and insert a needle to draw out the fluid collected within the joint. This fluid is then sent for further testing to exclude other conditions or other types of arthritis.
Can osteoarthritis be treated?
There is no cure for osteoarthritis. However, the symptoms can be managed. The guiding principle in the management is to treat the symptoms and disability, not the radiological appearances.
This is one of the most beneficial ways to treat the symptoms of osteoarthritis and this includes:
- Losing weight and maintaining it at a healthy range reduces the strain on the joints will be reduced.
- Regular exercises to strengthen and stabilize the joint are also useful.
- Gentle stretching of the joints will help to improve the flexibility of the joints as well as to lessen the pain and stiffness.
- Analgesics – These are pain relievers and should be always started with the most simple ones. Paracetamol should be the first to be tried and if it is not effective, opioids (narcotics) can be tried to reduce the pain. These are usually available over the counter or by prescription.
- Nonsteroidal anti-inflammatory drugs (NSAIDs) – NSAIDs aspirin and ibuprofen help in two ways – reduce the pain as well as the inflammation.
- Corticosteroids – Intra-articular corticosteroids provide short term improvement and are useful when there is accumulation of joint fluid.
This is an option for patients with severely damaged joints especially the hip or knee joint. Such patients will be referred to an orthopaedic surgeon to repair or replace the severely damaged joint.