The knee is the largest joint in your body and it is susceptible to injury. Because the knee is a complex joint, made up of many parts, there are numerous things that can go wrong. Knee damage is commonly caused by injuries to the joint.
Common Types of Sports Knee Injuries
- ACL Tear
- PCL Tear
- MCL & LCL Tear
- Meniscus Tear
- Cartilage Damage
Anterior Cruciate Ligament (ACL) Tear
The Anterior Cruciate Ligament (ACL) is one of the four main ligaments in the knee. The ligament connects the thigh bone to the shin bone, keeps the knee from hyper extending, prevents anterior dislocation at the tibia, and stabilizes to help prevent unnatural movement in the joint. If the knee is twisted, bent side to side, or hyper extended during physical activity the ACL can be injured. Contact sports involving rapid twisting movements may place harsh force on the knee, which can lead to injury.
There are several different types of ACL tears: a partial tear of the ligament, a complete tear of the ligament, also known as a rupture, and rarely the very end of the ligament remains attached to a small piece of bone which breaks or separates from the lower leg bone which is known as an avulsion. Many patients who sustain an ACL tear may opt to have surgical reconstruction of the ligament, which is most commonly performed arthroscopically.
Symptoms of a torn ACL will usually begin with swelling of the knee immediately after injury or within 24 hours. An ACL tear may cause a loud popping or cracking sound at the time of the injury. There may be some pain at the time of the impact, which over time may be felt in the calf region. The patient may feel some instability of the joint, perhaps creating the feeling of the knee "giving way."
Posterior Cruciate Ligament (PCL) Tear
A PCL injury is a less common occurrence than that of an ACL injury. This is due to the thickness and strength of the PCL. However, the most common way in which the PCL is injured is by direct force to the front of the knee, when it is bent. The PCL can also be injured by a direct blow to the outside of the knee joint, such as those that occur during soccer or football.
Symptoms of a PCL tear can vary depending on the instability in the knee. Patients usually see swelling in the back of the knee and bruising 24 to 36 hours after the injury occurred. The other major symptoms of a PCL tear include pain, excessive swelling and chronic instability.
Medial Collateral Ligament (MCL) & Lateral Collateral Ligament (LCL) Tear
The MCL connects the femur and tibia on the inner side of the leg and resists forces acting on the outer side of the knee. The LCL connects the femur and tibia on the outside of the leg and resists forces acting on the inner side of the knee. The two ligaments create support and stability for the knee. The MCL is more often injured than the LCL as injuries are often caused by a blow to the outer side of the knee, usually seen in contact sports, that stretches/tears the ligaments on the inner side of the knee. Symptoms of MCL and LCL tears often include pain, stiffness, swelling and tenderness along the inner or outer side of the knee.
A torn meniscus usually occurs when the knee is rotating while it is bearing weight. This type of injury often occurs in field sports such as soccer and football.
An injured or torn meniscus causes mild to severe pain depending upon the position of the leg and the extent of the tear. Swelling is common at the time of injury, but can develop much later. Many times, an injury to the meniscus causes a pop sound, or the knee may lock, or feel weak.
Cartilage acts like a natural shock absorber, preventing both bone on bone contact and providing a smooth, pain-free surface for the bones to glide against. Because cartilage does not have a blood supply to help repair damage, it may not heal quickly or at all. One of the most common and serious types of damage is to the articular cartilage that is between joints.
Symptoms of this articular cartilage damage include swelling, joint pain, stiffness, decreased range of movement and joints that lock or catch.
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