The knee is made up of bone, cartilage, ligaments, and fluid. Muscles and tendons linked to bone and each other help the knee joint to move smoothly and accurately.
This article on knee injuries is written by Jackie Griffiths, a freelance journalist who writes health, medical, biological, and pharmaceutical articles for national and international journals, newsletters and web sites.
When any of these structures are hurt or diseased it can lead to knee problems, causing pain and difficulty walking, and often in other parts of the body too.
Knee injuries are common, especially if you take part in sports. Sometimes the bones can be damaged, but it is far more likely that you will injure soft tissues such as ligaments and cartilage (meniscus). Minor injuries can sometimes be treated with physiotherapy but if the damage is more serious, surgery may be needed.
The most common knee injuries are:
- Sprains – overstretching the ligaments through twisting or wrenching
- Strains – overstretching the tendons or muscles
- Torn ligaments
- Torn menisci
- Bleeding in the knee joint – caused by a torn ligament
There are many ways to injure your knee, for example if:
- It receives an impact or is moved beyond its usual range of movement
- You play a sport that combines running, jumping, and stopping with quick changes in direction (such as football or netball)
- You have inflammation of the joint (osteoarthritis)
- Your knees hit the dashboard in a car accident
All soft tissue knee injuries are treated the same way. As soon as you experience this type of injury, you should follow the RICE procedure:
- REST the knee at the first, then reintroduce movement gradually so you don’t lose too much muscle strength.
- ICE packs should be applied to the knee to reduce swelling and bruising (use a cloth to protect the skin from ‘ice burn’).
- COMPRESS the joint by bandaging it to support the injury and reduce swelling.
- ELEVATE the knee and keep it supported.
You should see a specialist doctor (called an orthopaedic surgeon) for a complete diagnosis and find out what treatment, if any, is required.
Knee problems are diagnosed through a physical examination and a medical history check. Imaging tools such as an MRI, X-ray, CAT scan, or bone scan may be used to visualise the problem. However, sometimes these are not clear enough to provide a full diagnosis, particularly when the damage involves soft tissues around a bone. In this case, a minimally invasive surgical procedure, known as an arthroscopy, may be employed to evaluate the damage.
An arthroscopy involves passing a fibre optic camera through a small incision in the skin around the knee. A tissue sample may be taken during the process (this is called a biopsy). The entire procedure is done under a local or general anaesthetic.
Besides diagnosis, an arthroscopy is also used in treatment. A second incision is made in the skin and the surgical instruments are passed through. Soft tissues are repaired and unwanted materials are removed. The area may also be washed out with fluid to reduce stiffness caused by arthritis.
This is the most common form of knee surgery. As a keyhole procedure, there is far less risk of infection and recovery time is much faster. However, serious or complicated knee injuries may demand traditional surgery.
Physiotherapy helps restore function and movement in the damaged knee. It involves using specialist techniques and exercise programmes to treat knee injuries by strengthening damaged soft tissues over time and reducing pain and stiffness.
Physiotherapy exercises include: range-of-motion (for flexibility), strengthening (for greater support), and aerobic or endurance (to improve heart function and blood circulation and reduce swelling).
You can help prevent knee problems by doing the following:
- Warm up before playing sports; stretching the muscles in the thighs is a good way to warm up the knees
- Strengthen your leg muscles with certain exercises like walking up stairs, riding a bike, or working out with weights
- Avoid sudden changes in the intensity of exercise
- Gradually increase the force or duration of an exercise
- Wear shoes that fit well and are in good condition
- Maintain a healthy weight - extra weight puts pressure on the knees