Sudden knee pain can be the result of obvious events, such as a sports injury or the trauma due to an accident, but there are other ways that sudden knee pain can develop and some cases are not as obvious as a sports injury. The knee is an extremely important joint, and maintaining good knee health is extremely important.
Many of the sudden knee injuries experienced by athletes, and even people who are not athletes, involve what is known as acute ligament or cartilage tears. The knee is one of the most integral joints in the movement of the human body from one place to another, and it is also bears a great deal of the weight shift involved in moving rapidly from one point to another. Incidents of jumping, running for extended periods of time, sudden stops and sudden turns can cause acute tears in the ligament and cartilage material that holds the knee together. This pain can be quite sharp, and if it is not treated, it can turn into a chronic tear which will require surgery.
The muscles and tendons that cause movement in the knee have their physical limitations. Pushing them beyond their physical capacities can cause very small cuts and tears to appear, which can lead to achy knees. As these small tears begin to heal, they experience inflammation and this can lead to very severe sudden knee pain.
As the human body ages, the material that holds the knees together becomes weak and it begins to lose the elastic capabilities that allowed it to absorb pain in the past. In many cases, the deterioration of the tendons and ligaments in the knee can result in bone on bone contact. While the deterioration happens over a span of many years, the bone on bone contact pain can strike suddenly and without warning.
In some cases, sudden knee pain can be caused by a condition known as deep vein thrombosis. This is a blood clot that commonly occurs in the veins that run deep in the leg from the thigh down to the calf. If this clot lodges itself near the knee, then this can cause sudden and very severe knee pain.
If someone has not been active for a very long time, and then suddenly decides to engage in a vigorous athletic activity without properly warming up and stretching first, this will inevitably lead to sudden knee pain. The ligaments and tendons in the knee need to be stretched prior to engaging in any activity, and that is especially true if there is a level of atrophy due to a long period of inactivity.