Meniscal Tears
what is the meniscus?
There are two types of cartilage inside your knee.
The articular cartilage is the smooth glistening lining on the inside surface of your knee. This allows the knee to move freely. When this is damaged or worn away the result is arthritis.
The meniscus is the C-shaped disc of cartilage which sits inside the knee joint. You have one on each side of your joint. This acts as a natural shock-absorber, protecting the rest of your knee from damage during normal activity.
What is a meniscaL tear?
A meniscal tear is any condition in which the normal meniscus becomes damaged or torn. The most common reason for a meniscus to tear is after a sporting or twisting injury to your knee. With age the meniscus becomes softer, and can be torn with a relatively minor injury. In people with knee arthritis, a torn meniscus often happens as the arthritis develops. Meniscal tears are described based on the pattern and location of the tear. There are seven main types of meniscal tear:
Vertical / longitudinal tear - a tear in line with the meniscus.
Horizontal / flap tear - a tear which splits part of the meniscus.
Radial / transverse tear - a tear across the meniscus.
Oblique /parrot beak tear - a tear diagonally across the meniscus.
Buckethandle tear - a longitudinal tear in which the torn fragment has flipped into the middle of the knee (this is also known as a locked meniscus).
Complex tear - a combination of tear patterns. This is often see in degenerative tears.
Meniscal root tear - One end of the meniscus is detached from the bone.
What are the symptoms of a meniscal tear?
A meniscus tear often occurs during a twisting injury to the knee. You may feel or hear a ‘pop’, and the knee will usually swell over the next couple of days. Most people will feel pain in the knee mainly on the side of the torn meniscus, which is made worse by bending, squatting or twisting movements. Some people will experience catching or locking of the knee, and in rare cases the knee can become jammed so that it cannot fully straighten. Your knee may swell intermittently after activity, and you may feel a sensation of giving way when walking.
How is a meniscal tear diagnosed?
Most of the time, a meniscal tear can be identified based on your symptoms and clinical examination by an appropriately trained specialist. X-rays generally appear normal with a meniscal tear, but should be performed to make sure there are no problems with the bones in your knee. If your x-rays show signs of arthritis, then the torn meniscus is likely due to wear and tear, even if you have sustained an injury. If a meniscal tear is suspected, the best way to confirm the diagnosis and identify the type of tear is with an MRI scan. This will also show any ligament injuries which may have happened at the time of your injury.
What is the treatment for a meniscal tear?
The first stage of treatment for most meniscal tears is non-surgical. In the early stages after injury, applying ice and resting your knee will help to settle the swelling (effusion) in your knee. Simple pain relief such as paracetamol, and anti-inflammatory drugs such as ibuprofen, Voltaren or Celebrex are the best medication to help reduce inflammation. As soon as your knee is comfortable you should start low-impact exercises to maintain the muscle strength of your quadriceps muscles. The best way to do this is by regular daily use of a stationary exercise bike (exercycle) at low resistance. Other exercise such as swimming, using a rowing machine or performing physiotherapy exercises can also help. You will need to keep doing these exercises regularly for at least six weeks.
Many people who complete a course of knee rehabilitation will get better without the need for surgery. If you have ongoing pain and restriction of daily activities then surgery may be considered. If you have an associated ligament injury then there may be an indication for early surgery.
What does the surgery involve?
Almost all meniscal surgery can be done as a keyhole (arthroscopic) procedure. The type of surgery performed will depend on a number of factors, including the type of meniscal tear, how long the meniscus has been torn, your age, and whether you have signs of arthritis in your knee. The type of surgery can be:
Meniscectomy / Meniscal debridement
Meniscal repair
Meniscal root repair
What is a meniscectomy?
Removal of a damaged section of meniscus is called a meniscectomy. The meniscus has only a limited blood supply. This means that most meniscal tears will not heal, even with surgical repair. The best treatment in these cases is to remove the unstable damaged section. The remaining healthy section is left intact.
What is a meniscal repair?
If a meniscal tear is near the outer edges of the meniscus (where the blood supply is better) this can potentially be repaired. This is done using specialised arthroscopic surgical techniques in which the torn edges are stitched back together. The highest chance of success is in young patients, and if the surgery is done soon after injury. If your meniscal tear is surgically repaired and does not heal, a second operation to re-repair or remove the damaged section may be required.
What is a meniscal root repair?
The meniscal root is the end of the meniscus where it attaches to the tibia bone. If the root is torn, the whole meniscus is unstable and unable to perform its normal shock-absorbing function. Meniscal root tears generally need to be repaired by reattaching the meniscus to the bone using strong stitches.
What is the best treatment for a degenerative meniscus tear?
A degenerative meniscus tear occurs in a meniscus that has already been weakened by arthritis. In this situation it is always advisable to complete a full programme of knee rehabilitation before considering surgery. Arthroscopic surgery can remove loose or unstable portions of the meniscus and may help to improve mechanical symptoms such as locking and catching in the joint. Symptoms caused by the underlying arthritis such as aching pain, stiffness and swelling may persist, and may even be made worse by removing the remaining meniscus. If there is significant arthritis you may need to consider alternative treatments such as anti-infammatory medication, joint injections, or even joint replacement surgery.