Osteoarthritis of the knee either develops in the joint between the femur and the patella (35% of cases), or in the joint between the femur and the tibia (65% of cases). If the entire joint is affected, it is referred to as tricompartmental gonarthrosis. Osteoarthritis of the knee is a chronic disease that often affects both knees at the same time.
Symptoms of Osteoarthritis of the Knee
Osteoarthritis of the knee is the third most common form of osteoarthritis, and one of the most disabling. The disease often develops gradually. It initially causes discomfort and pain when moving. These symptoms are often more marked when the joint is used (such as when walking, going up or down the stairs, or carrying something heavy) and fade when sitting or lying down. People often complain of stiffness in the knee upon waking in the morning, and needing a little time to “loosen up”.
When the disease is at an advanced stage, pain can be felt throughout the day. Lumps, swelling, and/or crackling inside the joints are also associated with osteoarthritis of the knee.
Causes of Osteoarthritis of the Knee
In most cases, osteoarthritis of the knee is caused by a combination of several factors. These include misalignment in the legs, poor posture, and/or excessive strain on the joint (being overweight or carrying heavy loads). Not doing enough exercise can also play a role.
This condition is probably more common than case numbers would suggest. It can remain asymptomatic (which means that the person does not know they have it). It is often therefore discovered by chance during other medical examinations.
Risk Factors
Being overweight is the leading risk factor for developing osteoarthritis of the knee, followed bywear on the joint*Refers to the gradual change in the cartilage found in joints. and ligament injuries*Ligaments are very strong tissues that connect the different parts of a joint (cartilage). Some accidents (in particular when playing sports) can cause ligament damage or even tears, which can require surgery. caused by playing high-impact sports (such as football or rugby) or doing a high-risk job in terms of this disease (a job that involves handling heavy objects). Young people can also be diagnosed with osteoarthritis of the knee after an injury such as a tear of the anterior cruciate ligament or meniscus.
More generally, osteoarthritis of the knee becomes more common with age, and women, particularly after the menopause, are more likely to suffer from it. Osteoarthritis of the knee is also often caused by a misalignment in the legs, with knees that tilt inwards (knock knees) or outwards (bow legs).
Treating Osteoarthritis of the Knee
It is standard practice to consider surgery to replace the knee with a prosthesis only if non-surgical treatment has not yielded satisfactory results. It is therefore the last resort.
Non-invasive treatment should be tried first. This can include:
- the use of a knee support,
- nutrition and dietetics support (if the patient is overweight),
- mobilization of the joint by means of physiotherapy exercises*An allied health discipline that treats bone, joint, and muscle conditions using tailored physical manipulations and massages,
- the prescription of painkillers, anti-inflammatories, and injections (for example, corticosteroids).
If these measures do not relieve the pain, reduce joint inflammation, and therefore preserve knee mobility, a knee replacement may be needed. This implant replaces the damaged parts of the knee to provide support and recreate some level of mobility in the joint. A partial prosthesis can sometimes be fitted.
Progression and Possible Complications
Osteoarthritis of the knee is a degenerative disease, which means that symptoms get worse if left untreated, significantly impacting quality of life. Surgery for osteoarthritis of the knee, which involves implanting a prosthesis, is well established but does come with some risks (for example infection, post-operative bleeding, deep vein thrombosis*Formation of a blood clot in a vein that stops blood flow. It can cause serious complications if not treated properly or loosening of the prosthesis*A knee prosthesis is made up of several parts. Over time, the fixation of the prosthesis to the bone can deteriorate and cause the prosthesis to loosen. If that occurs, a gap forms between the bone and the prosthesis. This can be caused by natural wear and tear, but also by an infection or implants that were not correctly positioned. over time).
Preventing Osteoarthritis of the Knee
The best way to prevent osteoarthritis of the knee is through a healthy lifestyle:
- by doing plenty of low-impact exercise (cycling or aquafit),
- by eating a healthy diet and keeping an eye on your weight,
- by limiting the amount of alcohol consumed,
- by avoiding lifting heavy loads too frequently,
- by following the doctor’s advice regarding joint care and adopting an ergonomic desk set-up if needed,
- by not smoking.
It is particularly important to keep the muscles surrounding the joint strong by staying active.
When Should You Contact the Doctor?
Knee stiffness in the morning, pain in the knees when exercising, and swollen knee joints are signs of cartilage*Cartilage is a dense and stretchy tissue found where many bones in the human body meet. It acts as a shock absorber during movement. so talk to your doctor if you experience them.
Care at Hôpital de La Tour
A full clinical assessment is required to diagnose osteoarthritis of the knee, which includes taking the patient’s medical history and performing medical imaging. This diagnosis will be made by a rheumatologist, a sports physician, or a knee surgeon. These examinations allow the physician to assess how advanced the disease is and its severity. They also allow the physician to rule out any other conditions that could explain the symptoms. It should be noted that there are no blood markers for osteoarthritis of the knee, so blood tests are therefore not needed to make a diagnosis.