What is it?
Patella tendon rupture is a disruption of the tendon which attaches the knee cap to the tibia, which is the main bone in the lower leg. The patella tendon works with the quadriceps muscle to straighten the knee. Ruptures are rare but serious. The most common mechanism of injury occurs when the quadriceps muscle contracts forcefully while the knee is bent.
Who Is At Risk?
Patients who are at risk are those with inflammatory arthritis, chronic renal disease, diabetes, prior injury to the knee, history of patella tendonitis, fluoroquinolone antibiotic use, and/or corticosteroid injections. It is more common in males and those in their 3rd and 4th decades of life.
What are the Symptoms?
Patients will come experience a “pop” while playing sports or exercising. Tears that are chronic or incomplete may present as pain below the knee cap. Patients may also reports difficulty with weight-bearing on the affected leg.
What are the Signs?
The knee is often swollen and painful. The patient may not be able to fully straighten their knee and it may feel unstable.
How Is It Diagnosed?
Sports medicine physician will examine your knee looking for swelling, bruising, and pain around the patella tendon. X-rays may be of use to determine if the patella is abnormally high. Further imaging with an ultrasound or MRI may be used to evaluate the tendon for rupture.
How Is It Treated?
Partial ruptures of the patella tendon may be treated by immobilizing the knee for 6 weeks followed by physical therapy. Complete ruptures require surgery to re-attach the tendon. This procedure should be done within 1-2 week of injury. Surgery is followed by physical therapy to regain motion and strength.
When Can I Return to Play?
If surgery is required the patient should expect to refrain from sports for at least 6 months or longer pending progress. For those who don’t require surgery they may return to sports in 2-3 months.
Written by: Dr. Derek Worley