The knee joint is the largest joint in the human body. This means there is a lot of room for things to go wrong. Knee pain most often strikes during sports or recreational activities and during work- or home-related projects or tasks.
The most common cause of knee pain is injury. The knee joint may sustain acute injuries or overuse injuries. Acute injuries can be caused by a direct hit to the knee: irregular twisting and/or bending; and falling. These actions may also cause pinching and damage to nerves and blood vessels, which leads to pain.
Overuse injuries occur when a person engages in activities that repeatedly aggravate the knee and expose it to long periods of pressure. Overexertion from exercise, running, jogging, jumping or climbing stairs puts stress on the knee and its surrounding tissues and ligaments and leads to inflammation, irritation and pain.
Other causes of knee pain include osteoporosis, blood clots and arthritis.