The knee is a complex joint which consists of bone, cartilage, ligaments and tendons that guide and control joint movements but which remain susceptible to various kinds of injuries. Knee problems may arise if any of these structures get injured by overuse or suddenly during sports activities. Pain, swelling, and stiffness are the common symptoms of any damage or injury to the knee. Common causes of knee injury include:
- Fracture of the femur (thigh bone) or tibia and fibula (leg bones)
- Torn ligaments (eg. anterior or posterior cruciate ligaments)
- Torn cartilages (meniscal cartilage or of the ‘lining’ cartilage)
- Rupture of blood vessels following a trauma that leads to accumulation of extra fluid or blood in the joint
- Dislocation of knee cap (patella)
- Torn quadriceps or hamstring muscles
- Patellar tendon tear
Anterior Cruciate Ligament (ACL) tear
An ACL injury is a sports related injury that occurs when the knee is forcefully twisted or hyperextended. An ACL tear usually occurs with an abrupt directional change with the foot fixed on the ground or when the deceleration force crosses the knee. Changing direction rapidly, stopping suddenly, slowing down while running, landing from a jump incorrectly, and direct contact or collision, such as a football tackle which can also cause injury to the ACL.
Medial Collateral Ligament (MCL) tear
The medial collateral ligament (MCL) is the ligament that is located on the inner part of the knee joint. It runs from the femur (thigh bone) to the top of the tibia (shin bone) and helps in stabilisation of the knee. Medial collateral ligament (MCL) injury can result in a stretch, partial tear, or complete tear of the ligament. Injuries to the MCL commonly occur as a result of a pressure or stress on the outer part of the knee.
Posterior Cruciate Ligament (PCL) tear
PCL injuries are very rare and can be more difficult to detect than other knee ligament injuries. Cartilage injuries, bone bruises, and other ligament injuries often occur in combination with PCL injuries. Injuries to the PCL can be graded as I, II or III depending on the severity of injury. In grade I, the ligament is mildly damaged and slightly stretched, but the knee joint is stable. In grade II there is a partial tear of the ligament. In grade III there is a complete tear of the ligament and the ligament is divided into two halves making the knee joint unstable.
The PCL is usually injured by a direct impact, such as in an automobile accident when the bent knee forcefully strikes the dashboard. In sports, it can occur when an athlete falls to the ground with a bent knee. Twisting injury or overextending the knee can cause the PCL to tear.
Lateral Collateral Ligament (LCL) and postero-lateral corner
LCL injury may be caused by a direct blow from the inside of the knee or with a twisting injury. It is commonly associated with an injury of the postero-lateral corner injury which is a complex arrangement of ligaments and tendons which help to control knee movement.
Immediately following a knee injury before being evaluated by a doctor, you can initiate the R.I.C.E. method of treatment:
- Rest: rest the knee as more damage could result from pressure on the injury
- Ice: Ice packs can be applied to the injured area to reduce swelling and pain. Never place ice directly over the skin. Ice should be wrapped in a cloth covering and applied to the affected area for 15-20 minutes four/five times a day, for several days
- Compression: Wrapping the knee with an elastic bandage or compression stocking can help minimize the swelling and support your knee
- Elevation: Elevating the knee above the level of your heart when lying down will also help reduce swelling and pain.
It is important to seek your surgeon’s advice if you hear a popping noise or feel as if your knee has given way at the time of injury and if you are unable to use your knee because of instability or pain.