What is osteoarthritis?
Osteoarthritis (OA) is one of the five leading causes of disability among elderly men and women. It affects approximately 8 million people in the UK. The risk for disability from osteoarthritis is as great as that from cardiovascular disease.
Arthritis is called many different names including, arthrosis, osteoarthritis and degenerative joint disease.
The ends of the bones in joints are covered in a beautiful smooth surface (articular cartilage) that allows them to glide over each other like ice on ice. In arthritis, the smooth surface covering of the end of the bones is lost so instead of gliding like ice on ice it moves like concrete on concrete, catching, giving way and causing pain.
The lining of the knee (synovium) becomes inflamed and thickened. It produces extra fluid causing swelling.
The bone reacts and becomes thicker. Additional bits of bone grow (osteophytes) often causing stiffening of the joint.
The joint capsule and ligaments slowly thicken and contract reducing movement of the joint, often stopping a patient fully straightening the joint.
What causes osteoarthritis?
Arthritis develops due to damage to the articular cartilage. This is due to either normal forces through abnormal cartilage, or abnormal forces (usually excess weight) through normal articular cartilage. Sometimes the cause is not known.
There is often a combination of factors causing arthritis.
Several factors may increase the risk of developing osteoarthritis:
- Age – Osteoarthritis usually begins to develop in the late 40’s. The ability of cartilage to heal itself decreases with age.
- Obesity – Increased weight puts increase force through the joint. Obesity is also associated with reduce levels of exercise which is important in maintaining joint health.
- Joint injury – An injury or operation to a joint may lead to OA. If the joint is unstable due to injury, OA can result.
- Exercise and activity – Normal exercise and activity is good for joints but repetitive small overloading of a joint associated with some occupations has been implicated in the development of arthritis.
- Heredity – Some people are genetically predisposed to developing arthritis. The basis for this is unknown.
- Gender – OA is more common in women and tends to be more severe.
- Joint abnormalities – If the joint is not correctly aligned, especially the knee (knocked or “bandy” knees) excess force will occur. Congenital (birth) joint problems often lead to arthritis.
- Other illnesses – Repeated episodes of gout, infection, metabolic disorders and some congenital conditions can also increase your risk of developing osteoarthritis.
What are the symptoms of OA?
The main symptoms are usually pain and stiffness. Any moving joint can be affected but the knees, hips, hands, spine and the big toe are areas commonly affected.
The pain tends to be worse with activity. As the disease progresses the pain may be present even when resting and may affect your sleep.
The joint may appear swollen either because of the extra fluid produced or due to the extra bone (osteophytes) produced.
If the joint is not working properly the muscles around it tend to waste. This, with the joint damage, can cause giving way.
As the disease progresses the bone can be worn away causing the joint to go out of alignment (bowed or knocked knees).
Everyday activities can be affected such as climbing stairs, getting in and out of chairs and tying shoe laces.
In the early stage the symptoms often come and go with people having “good and bad days”.
Which joints are affected?
- Knee – The knee is commonly affected, probably due to the huge twisting forces put through it. Damage to the menisci (shock absorbers) or ligaments of the knee often cause OA. The knee is made of three different compartments; one or all can be affected.
- Hip – The hip is also commonly affected. The pain is usually felt deep in the groin but can also be felt in the buttock or side of hip. The pain may go down the thigh to the knee. Patients often walk with a limp and have problems getting down to their feet or putting on socks/shoes. Congenital (birth) or development (Perthes) problems often cause OA.
- Hand – Women are more commonly affected than men. It usually affects the base of the thumb and joints at the ends of the fingers. The joints may become knobbly.
- Spine – The bones and discs in the spine are often affected and is sometimes called spondylosis.
- Foot – Arthritis at the base of the big toe is common. If it swells it may cause problems with finding/wearing shoes. Movement may be reduced (hallux rigidus) and the toe may bend over to the side (hallux valgus).
How is osteoarthritis diagnosed?
There many different types of arthritis and they may be treated differently.
The diagnosis is made by your doctor taking a full history, examining you and then performing tests.
Symptoms (what you feel)
- Inability to maintain muscle mass.
Signs (what the doctor sees)
- Swelling (fluid and bony in the knee).
- Reduced movement.
- Pain on moving the joint.
- Noise on moving the joint.
- Muscle wasting.
There is no blood test for osteoarthritis, but they may be taken to rule out other types of arthritis.
The commonest test is to undertake an x-ray. At first this may not show many changes. As the condition progresses the gap between the bone ends reduce (joint space narrowing), extra bone is seen (osteophytes) and the thickened bone is seen (sub chondral sclerosis). X-ray changes may not match the amount of pain you are experiencing.
How is osteoarthritis treated?
Treatment of arthritis is outlined in the government NICE (National Institute of Clinical Excellence) guidelines.
Initial treatment is generally directed at pain management. A wide range of treatment options are available and treatment is tailored to the individual. You and your doctor should decide together on the course of treatment that is right for you.
In general, treatment options fall into five major groups:
Self help/ behaviour modifications
- Patient education – Understanding the condition can help deal with the problem. Pace yourself during the day, do heavy jobs a bit at a time. Rest if the joint is painful. Shock absorbing shoes (i.e. trainers) or insoles help.
- Walking sticks help reduce the force through the joint.
- Hot and cold packs can help, being careful not to freeze or burn the skin.
- Weight loss – Being overweight increases the forces through your joints, especially your knees. Up to 5-6 times your body weigh is transferred through the joint when running or going up and down stairs. Therefore 1 stone overweight is the equivalent of 5-6 stone through the knee, 2 stone equivalent to 10-12 stone etc. Small amounts of weight loss can make a big difference.
- Exercise – Exercise is beneficial in helping to maintain muscle strength and helps reduce weight. The muscles act like shock absorbers helping to protect the joint. Non impact loading activities, such as swimming and cycling are usually better tolerated. Little and often is best. It is important to try and maintain the full range of movement of the joint, especially straightening of the knee. Simple exercises such as lying on the floor pushing your knee down flat are useful. Physiotherapists often undertake “hip and knee classes” to help show patients with arthritis the exercises they should be undertaking.
- Avoid activities that are going to make you worse.
- Simple painkillers – Paracetamol can be very effective. Make sure you take the correct dose (1g (usually 2 tablets) 4 times a day) as most people take too little.
- Stronger painkillers – These often contain paracetamol and codeine (co-dydramol, co-codamol). Opioid painkillers, such as tramadol, are used for more severe pain. With stronger pain killers it is commoner to experience complications such as nausea, dizziness, confusion, tiredness and constipation. Some opioids are given as small patches that are worn on the skin.
- Non-steroidal anti-inflammatory drugs (NSAID’s) – These are often used when paracetamol is not effective or if there is a lot of swelling in the joint. Ibuprofen and naproxen are common examples. Like all drugs they can have side effects and should not be used, or used with caution, in people with asthma, kidney problems and indigestion. They carry a small increased risk of stroke and heart attack. Patients with increased blood pressure, circulation problems, high cholesterol and diabetes should consult their GP
- Topical pain reliving creams may be helpful.
- Corticosteroid (steroid) injections – These are injections of steroid and local anaesthetic directly into the joint. They are normally used during acute exacerbations of pain and swelling or to help people through important events, such as weddings. They may take some time to work, last from a few days up to a few months. There can be a flare of pain immediately following the injection lasting for a few hours or days.
- Hyaluronic acid (viscosupplementation) – The normal lubricating fluid in the knee becomes thinner in arthritis. These injections introduce a thick fluid into the knee. The evidence for its effectiveness is still being researched.
Many people use and feel benefit from complementary medicine and treatments, although there is little or no scientific basis to there use.
- Glucosamine and/or chondroitin sulfate – These compounds are found in joint articular cartilage. 1.5g needs to be taken for a minimum of 3 months. Most brands of glucosamine are made from shellfish so should be avoided if you have an allergy. Glucosamine may also affect your blood sugars if you are diabetic.
- Acupuncture – This may be helpful for short term pain relief.
There are many different operations that can be performed for arthritis depending on the problem and stage of the disease. Some of the operations are:
- Arthroscopy – looking inside the joint, getting rid of rough edges or loose flaps of articular cartilage. Any tears of the biological shock absorbers in the hip or knee can be removed.
- Osteotomy – bones can be cut and the leg realigned so the weight passes through a less damaged part of the joint.
- Arthroplasty – when all or part of the joint is replaced.