Osteoarthritis is a form of arthritis that develops when the cartilage cushioning bone ends in the joint wears down over time. It is also the most commonly encountered form of arthritis. Osteoarthritis affects millions of North American adults in their middle-aged or later years. The areas most commonly affected are the hands, knees, hips and spine.
As with many other forms of arthritis, osteoarthritis causes pain, stiffness and swelling of the affected joints. It mainly affects adults over aged 60 and tends to attack one side (i.e. left or right) at a time.
There is no fundamental cure for osteoarthritis (i.e. no measures doctors can take that will eliminate or reverse the damage to joints). Instead, doctors usually try to manage the severity of its symptoms and slow the rate of progression of the disease. They will also try to preserve as much joint range of motion and function as possible.
Causes Of Osteoarthritis
As mentioned above, osteoarthritis is a result of the breakdown of bone cartilage. This causes the bone ends to rub directly against each other.
Cartilage is a tough but slippery mass that covers the ends of healthy bones. It allows the bones to glide smoothly and frictionlessly over each other as someone moves the joint.
Hence, the result of cartilage deterioration means that bone starts to rub directly against bone. This causes increasing joint pain and stiffness when the affected individual tries to move the joint.
The cartilage breakdown may be the result of wear and tear over time. It may also be the result of an earlier injury that causes the joint bones to be closer together. This can then cause increased bone on bone contact. This then causes faster cartilage breakdown than would otherwise be the case.
The effects of osteoarthritis, however, are not limited to the lining of bones in the joint. As time progresses, the disease also changes the shape of the bones themselves. It may also alter the connective tissues holding the joint together and attaching muscle to bone. Inflammation of joint lining is also a factor that creates the joint pain and stiffness characteristic of the disease.
Risk Factors
There are several factors that can increase the probability that an individual may develop osteoarthritis. These include:
Age – the incidence of the disease increases with age;
Gender – it occurs more often in women than in men
Excess body weight increases the risk of osteoarthritis. This is because it places more pressure on weight bearing joints like those in the hips, knees and spine;
Previous joint injuries – as mentioned above, previous injuries can sometimes change the relative positions of joint bones. This can cause the bones to contact each other more frequently or in a different way than intended.
Shifting of joint bones can happen with a joint infection or a previous fracture in the bone near a joint. It can also be the result of a previous ligament injury leading to joint instability. This can result in increased osteoarthritic risk;
Occupation or sporting activities – certain occupations or sports can place additional and repeated stress on joints. This can increase the risk of osteoarthritis (OA). For example, it is thought that being an elite athlete may predispose to OA of the knee. Working with pneumatic drills may predispose to OA of the elbow;
Genetic factors – in some cases, individuals may inherit an increased osteoarthritic risk through a gene;
Having diabetes or hemochromatosis (a condition in which your body has above normal amounts of iron) can increase your osteoarthritis risk.
Osteoarthritis Symptoms
It is unusual for osteoarthritis to develop in people below the age of 40 years.
Osteoarthritis has many symptoms in common with other forms of arthritis. The most typical symptoms experienced by people with osteoarthritis are:
Joint pain during or after physical activity;
Joint stiffness. This, unlike arthritis pain, is usually at its worst just after the patient has awakened or after a period of inactivity;
A feeling that the joint is “tender to the touch”;
Lost range of motion of the joint;
Crepitus, or a popping or cracking sound when the patient tries to move the joint;
Formation of additional lumps of bone (bone spurs) around the arthritic joint;
Swelling and deformity of the joint in advanced disease
When the disease strikes, it usually (although not invariably) produces joint damage on one side only. This is in contrast to some other forms of arthritis such as rheumatoid arthritis, which usually develop on both sides simultaneously.
Quite unlike rheumatoid arthritis, osteoarthritis does not cause any systemic symptoms.
Possible Complications
Possible complications include a progressive loss of ability to carry out normal activities of daily living without pain and discomfort. As the disease progresses, even simple things like taking a walk, bathing and dressing become increasingly painful.
A badly affected knee or hip joint can cause poor mobility and problems walking. This could also predispose to falls. Bad OA of the hip can make it difficult to put on shoes and socks. It can also make it difficult to get in and out of a car.
In extreme cases, affected individuals will go to extreme lengths to avoid the daily pain and discomfort of the disease. For example, they may stay in bed longer to avoid having to move.
The pain can nevertheless be experienced even while sleeping, so sleep disturbance is another possible complication.
The net effect of these developments can be the onset of depression as the patient’s quality of life deteriorates.
Diagnosis Of Osteoarthritis
Physical Examination
The first step in diagnosing the cause of joint pain and stiffness may be a physical examination of the affected joint. The doctor will look for signs such as tenderness, swelling, redness and loss of range of motion (i.e. reduced flexibility).
The doctor may also review the patient’s medical history. Of particular interest will be previously experienced injuries of or near the affected joint. These may be causing the osteoarthritic symptoms the patient is experiencing. As mentioned above, some injuries can change the joint and increase the risk of later osteoarthritis development.
Most cases of OA can be diagnosed based on age, history and clinical examination. Tests like blood tests and X-rays are not usually needed.
Imaging Tests
Once the physical examination has been completed, the doctor may request a series of imaging studies. The doctor may sometimes order X-rays or other tests if she wants to exclude other problems. These will provide a better idea of what is going on inside the affected joint.
The specific studies requested may include:
X rays to reveal any narrowing of the distance between bones in the joint (possibly due to loss of bone cartilage). X rays can also reveal any bone spurs that may have developed in the joint (osteophytes) and/or bone cysts;
The doctor may feel that there is additional joint damage that is not fully understood. If so, an MRI study may be requested to provide more information about the structures inside the joint.
Laboratory Tests
As final confirmation of the indications of the physical examination and imaging studies, doctors may request testing of patient blood samples. They may also test fluid drawn from the affected joint.
The blood test results can help to eliminate other conditions e.g. rheumatoid arthritis that may also be causing joint pain and stiffness or gout.
Joint fluid can be tested for inflammation and/or bacteria that may identify other conditions. These may for example include gout (an inflammatory form of arthritis). Joint fluid can also reveal an infection like septic arthritis that may be causing the patient’s joint pain.
Treatment
There are some home based treatments that one can use for mild cases of osteoarthritis, such as:
Gentle walking or running;
Low impact exercises such as gentle swimming or cycling;
For cases of knee osteoarthritis, an unloader knee brace can be effective in reducing knee pain. It can also slow the rate of cartilage deterioration.
The home based exercises will help to improve joint function for those with mild cases of the disease. This will help them to maintain the ability to perform routine tasks without too much pain. For even more progress, the physical therapy exercises mentioned below can also be considered.
Doctor based treatment plans for osteoarthritis can be classified into three groups – medications, therapy treatments and surgery.
Medications
Osteoarthritis patients may be prescribed pain relief medications, including:
Acetaminophen (Tylenol) or other similar pain relief drugs if the pain is not severe;
Non steroidal anti inflammatory medications such as Ibuprofen or Naproxen may be taken to reduce pain if it is severe. Usually, topical anti-inflammatory painkillers like ibuprofen gel are recommended in preference to tablets. This is because a much smaller quantity of the drug is absorbed into the bloodstream. The risk of side-effects is therefore smaller than with tablets.
These topical preparations are particularly suitable for OA of the knee or hand. Doctors may ask the patient to report any side effects such as stomach upset. In addition, they themselves will likely monitor for cardiovascular problems or organ damage;
If there is inadequate response to Tylenol and NSAIDs, opioids such as codeine can be considered
Cymbalta – an antidepressant drug that may also be effective if taken to relieve pain such as that from osteoarthritis.
Therapy Treatment Plans
These can include:
Physical therapy exercises to strengthen joint muscles and improve range of motion. Strengthening the quadriceps muscles has been shown to improve symptoms caused by OA of the knee. Another role of physiotherapy is to give advice on shoes, insoles, knee braces and how to use walking aids properly;
Occupational therapy can help the patient to modify daily activities or equipment around the home to relieve arthritic pain. An example of this would be the provision of a tap turner to help with turning on a tap;
TENS therapy, which uses a low level electrical signal to reduce pain. Small electrical pulses are delivered to the body via electrodes placed on the skin.
Surgical Intervention Options
These may include:
Cortisone injections into the affected joint to combat inflammation;
Injections of hyaluronic acid, a lubricating agent. This is typically used with cases of patellofemoral osteoarthritis;
Joint replacement surgery, of which the most well known types are knee and hip replacements. There is a time limit on how long an artificial joint will last. As a result, this intervention is not usually performed in people below the age of 55 years.