A hyperextended knee is a common sports injury that can vary in severity from a mild and temporary inconvenience to a major knee injury. Symptoms of a hyperextended knee can include swelling, pain, bruising, and ligament damage. In a hyperextension, the ACL or another ligament of the knee can tear partially or completely. Treatments for a hyperextended knee depend upon how badly the joint has been damaged.
In a hyperextension, the knee bends beyond its normal range of motion and puts a great deal of stress on the ligaments of the knee. Symptoms of a hyperextended knee can include pain, swelling of the joint, bruising around the effected area, difficulty walking, or other difficulty with joint use and movement. When it yields any of these symptoms, the Mayo Clinic recommends obtaining medical attention as soon as possible.
To diagnose a hyperextended knee or its associated injuries, tests can include an MRI, X-rays, and a CT scan. An MRI can identify ligament damage, which in the case of a hyperextended knee can involve a tear of the ACL (anterior cruciate ligament). In a mild hyperextended knee, symptoms are generally limited to temporary tenderness and discomfort. However, in a severely hyperextended knee, symptoms can include swelling, pain when any pressure is applied, and a popping sound at the time of the injury.
Treatments for a hyperextended knee depend largely on the severity of the injury. When there is no ligament damage or damage to other surrounding tissue, hyperextended knee treatments can be as simple as rest, icing the effected area, and strengthening the surrounding muscles. A doctor may suggest using crutches or wearing a knee brace to ease back into normal daily activity.
A common treatment for hyperextended knees is to strengthen the surrounding muscles through exercise or physical therapy. This helps to reestablish full knee strength and function and to prevent a recurrence of the injury. As with other treatments, the specific regimen will depend on the severity of the injury.
When a hyperextended knee causes a torn ACL, the major treatment is often surgery. This mainly applies to athletes as ACL reconstruction is a major surgery. Recovery can take several months, typically between six and nine months, and as long as a full year. A partially torn ACL does not require surgery, but the treatment depends primarily on the patient.
Hyperextension can often affect players of sports like basketball, soccer, and football, as well as gymnasts, and any other athletes who engage in a lot of jumping, frequent lateral movement, and high speed direction changes. Yoga, dance, and other fields that involve a great deal of flexibility can also increase the odds of a hyperextension.
To reduce the risk of suffering a hyperextended knee or any of its associated injuries, avoid locking the knee or fully extending it. Weak surrounding leg muscles can also increase the risk of a hyperextension, so regularly engage in leg strengthening exercises like running, biking, squats, wall slides, leg lifts, toe lifts, or stair stepping. Any questions about symptoms or treatments for a hyperextended knee should be directed to a doctor.