The Medical Minute: Knee pain -- when should you be concerned?

September 09, 2008

By Kevin Black

Knee pain and knee injuries are extremely common in athletics and can be anxiety provoking for not only the player but parents and coaches as well. Understanding the discomfort and possible causes can be helpful in determining when you can "play through it" versus when you should seek medical advice. Several factors should be taken into consideration including onset, swelling or deformity, and severity of discomfort.

The most common knee complaint encountered in sporting activities is related to overuse and typically manifests as a generalized aching knee discomfort that is increased by bent knee activities such as kneeling, squatting and stair climbing in addition to the recreational activity itself. Oftentimes it occurs in association with a change in training regimen, including increased running distance or intensity, change in running terrain, or lower-extremity weight training. Symptoms are usually gradual in onset without a particular traumatic event, and there is no noticeable deformity. Treatment usually lies in the recognition that this is an overuse condition and identification of what precipitated the onset of symptoms. Early reduction of activities to a pain-free level, limited use of over-the-counter pain medication, quadriceps and hamstring stretching exercises and the application of ice after the activity usually result in rapid symptom resolution. While symptoms are improving, it is reasonable to remain active but at a level that is not painful.

At the other end of the spectrum is knee pain that results from a specific traumatic event. Although the discomfort might be secondary to something as simple as a bruise, there might be a more serious condition present. An all-too-common scenario is that of the high school athlete who sustains a twisting injury to their knee, resulting in swelling within 12 hours. In 70-80 percent of cases, this represents a tear of the anterior cruciate ligament. Less common are other conditions such as meniscus tears, other ligament injuries or instability of the kneecap. The important thing to recognize is that any traumatic event to the knee that is accompanied by swelling should be taken seriously, as in greater than 95 percent of cases there is significant structural damage to the joint. You should consult your athletic trainer or physician immediately for evaluation of these injuries.

Obviously, knee pain and injuries don’t always fit neatly into one category or the other. If you experience severe pain, notice any deformity or have significant difficulty with walking, you should also be evaluated by your athletic trainer or physician.

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Kevin P. Black is professor and C. McCollister Evarts chair at Penn State Milton S. Hershey Medical Center, Penn State Hershey Bone and Joint Institute.

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Last Updated March 19, 2009