This condition occurs when the tendon that holds the patella, (the knee cap), to the tibia tears and splits apart, allowing the patella to slide upward. This causes pain and an inability to straighten the knee.
A patella tendon rupture is usually caused by direct trauma to the front of the knee. If the knee has been injured before, small tears may have developed in the patella tendon, making it more likely to rupture.
The most common symptoms for a ruptured patella tendon are immediate, intense pain, and an inability to straighten the knee. Other symptoms include swelling, bruising, and hearing a snap or pop during injury. The patella may appear higher up the knee than usual, or may feel loose.
Treatment options include rest, cold compress, anti-inflammatory medications, elevation of the affected leg, and immobilization of the leg in a straightened position. Surgery is commonly required.