Because you use your knees for most athletic motions in an upright position (i.e. running, jumping), the knee is one of the most frequently injured areas. Twisting, turning, quick starts and stops all put stress on your knees. The most common acute knee injuries are dislocation of the kneecap and injuries to the ligaments. Knee injuries can also make you more susceptible to other problems like tendinitis and arthritis. Most often, trauma happens when you twist or wrench the knee. Certain sports can place unusual demands on the knee.
Knee Sprain/Strain:
A knee sprain stretches ligaments in the knee, while a knee strain involves the muscles or tendons around the knee.
Mild sprains tear some ligament fibers, but you still have function. A moderate sprain ruptures some of the ligaments and some function is lost. A severe sprain is a complete rupture of the ligament or separation of your ligament from the bone.
A moderate strain tears muscle or tendons and you lose some strength. A severe strain ruptures muscle and tendon attached to the knee.
Severe sprains and strains can result in a full loss of function and you may need surgery.
Symptoms of knee sprain and strain include:
- Pain, soreness and stiffness (strain)
- Popping or tearing sensation in the knee (sprain)
- Weakened knee
- Muscle spasms and loss of strength
- Tenderness and swelling
Knee Cartilage:
Twisting the knee, landing on it, or receiving a blow can injure your knee's cartilage at the top of the lower leg bone (tibia). Knee cartilage injuries are often associated with kneecap dislocation or ligament sprains in the knee.
Symptoms of knee cartilage injuries include:
- pain and tenderness in the knee, especially when you put weight on it
- the knee joint locks or gives way
- water on the knee
Runner's Knee:
Runner's Knee is an overuse injury of the knee. The surface behind the patella is damaged. Symptoms can worsen after running, walking, squatting or jumping.
Symptoms of Runner's Knee include:
- sharp aching pain behind your kneecap
- dull ache in the front of your knee
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