Knee injuries are common, especially when taking part in sport. Injuries to soft tissues, such as ligaments, cartilage and tendons are the most common. You can also damage the bones that make up your knee joint.
There are many different structures inside and outside your knee. These include:
Injury to your knee can damage any one or more of these structures.
Your knee ligaments help to keep your knee stable.
The medial collateral (MCL) and lateral collateral ligaments (LCL) are found on either side of your knee joint. They limit the amount your knee can move from side to side. You can sprain or tear your MCL if your lower leg gets forced outwards. For example this can happen when being tackled in rugby or when skiing. Your LCL is less commonly injured, and this is more likely to happen when you have also damaged other ligaments.
Your anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) form a cross (cruciate) inside your knee. They help to keep your knee stable. ACL injuries are one of the most serious types of knee injury.
If you have injured your MCL or LCL, your GP may grade your injury according to how severe the damage is.
There are other soft tissues around your knee that can be injured. Soft tissue means any tissue in your body that isn't bone.
Tearing the meniscus in your knee is one of the most common knee injuries. You can damage it if you play a sport that involves twisting your upper leg while your foot is planted on the ground. As you get older, your meniscus may become worn. This makes it more likely to tear after a minor injury or just getting out of a chair awkwardly.
If you’re a regular runner or take part in sports where you jump a lot, you may hurt your knee. You can irritate or tear the tendon that connects your kneecap (patella) to your thigh muscle. This tendon is called the quadriceps tendon. Or you may irritate soft tissue around your kneecap, including the patellar tendon, which is just below your knee cap (Jumper’s Knee).
You may feel or hear a popping or snapping when the injury happens. You may also find that you can't put your full weight on the injured leg.
The symptoms for most ligament injuries will be similar. These include:
If you injure the meniscus in your knee, you may feel a locking sensation and severe pain. Pain may develop towards the inside or outside of your knee joint and you may see some swelling.
If you have injured your knee and you think it’s more than a simple sprain, visit your GP or physiotherapist. Seek advice if it’s tender to the touch, very stiff, swollen, giving way, clicking painfully, locking or you can’t put your full weight on it.
You may injure your knee if:
Your GP or physiotherapist will ask about your symptoms and examine you. This may include feeling for fluid in your knee joint by pressing gently around your kneecap. He or she will also ask you to describe how your injury happened, where your pain is and what type of pain it is.
Your GP or physiotherapist may ask you to walk, sit or lie down. This is so he or she can test for injury to your knee ligaments or soft tissues. He or she will bend and straighten your knee and move your leg into different positions.
Your doctor may refer you for other tests in a hospital or clinic, which may include:
There are different types of treatment that your doctor or physiotherapist may suggest, depending on the type and severity of the damage to your knee. It’s important to be patient when recovering from a knee injury. Your injury may take time to fully repair itself, so you may not be able to do all the things you’re used to doing for some time. Different injuries require different rehabilitation, so it’s best to talk to your GP or physiotherapist.
You should follow the PRICE procedure for any soft tissue injury to your knee. PRICE stands for the following.
There are certain things you shouldn’t do in the first three days after your injury so you don’t damage your knee further. You can remember these as HARM.
You can buy over-the-counter painkillers such as paracetamol to treat mild and moderate pain. Over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen can help to reduce inflammation and swelling, as well as relieve pain. NSAIDs are available as gels, creams and sprays that you can put directly onto your skin, as well as tablets that you take by mouth.
Your GP may prescribe stronger painkillers if your pain is severe. Always read the patient information that comes with your medicine and if you have questions, ask your pharmacist or doctor for advice.
If your injury is more severe or complex, your GP may refer you to a physiotherapist (a health professional who specialises in movement and mobility). You can also choose to see a physiotherapist privately. He or she will develop a programme of rehabilitation exercises to gradually strengthen your knee and stretch your muscles. These exercises will vary depending on the type of injury you have and how severe it is.
Some people have braces or strapping to support the knee during rehabilitation, usually when an injury has been severe.
For some types of knee injury, your GP or physiotherapist may recommend that you have surgery to repair the damage to your knee – especially if other forms of treatment haven’t worked. Your GP will refer you to an orthopaedic surgeon for assessment.
The surgeon is more likely to suggest surgery if you have one of the following injuries.
You may be able to have a type of keyhole surgery called knee arthroscopy to access the damaged area of your knee. Rarely, surgery may involve opening up your knee joint to repair it.
There are some precautions you can take to try to reduce the risk of damaging your knee ligaments.
Reviewed by Natalie Heaton, Bupa Health Information Team, 30 August 2013.
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