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What Is a Patellar Tendon Rupture? 

The patellar tendon is actually a ligament that connects the patella, or kneecap, to the shinbone (tibia). A patellar tendon rupture occurs when the kneecap becomes completely detached from the shinbone. The rupture usually happens at the kneecap connection, rather than at the tibia. 

Patellar Tendon Rupture Symptoms 

A patellar tendon rupture is usually accompanied by a tearing or ripping sound, followed by pain and swelling. Other signs that the tendon has been torn include: 

  • Bruising 

  • Cramping 

  • Difficulty walking 

  • Inability to straighten the knee 

  • Indentation at the bottom of the kneecap 

  • Tenderness 

  • The kneecap moving up the thigh 

Causes of Patellar Tendon Ruptures 

A tear in a healthy patellar tendon is usually the result of an acute injury such as a fall or from a car accident. It can also happen while landing from a jump. 

The tendon can also be weakened by chronic conditions and overuse, making it more likely to tear. Chronic conditions that can lead to a weakened patellar tendon include: 

  • Chronic kidney failure 

  • Diabetes 

  • Infection 

  • Metabolic disease 

  • Patellar tendinitis 

Anabolic or corticosteroid use and prior knee surgery may also increase the risk of a patellar tendon rupture. 

Patellar Tendon Rupture Diagnosis 

A medical history and a physical examination are usually the first steps in diagnosing a patellar tendon rupture. The doctor will ask about prior knee surgery, chronic conditions and any event that preceded knee pain. After the medical history, the doctor will see how well the patient can bend and straighten the knee. 

Imaging tests are sometimes used to confirm a suspected diagnosis. X-rays can show that the kneecap is out of position, while magnetic resonance imaging (MRI) scans can show injury to the tendon itself. 

Treatment for Patellar Tendon Ruptures 

Surgery will be necessary to repair a ruptured patellar tendon. The surgeon will have to reattach the tendon to the kneecap by drilling holes into the kneecap and attaching the tendon with sutures, sometimes bolstered by wires. The knee will then be immobilized by a brace. 

After about two weeks, the sutures can be removed. At that point, the knee can begin to bear weight again, starting at about 50 percent of the total body weight. In four to six weeks the knee should be able to take on the full weight. 

Physical therapy (PT) will be important in recovery. The goals of PT include strengthening the leg muscles and increasing range of motion. The tendon should be completely healed in six to 12 months. 

If you are living with a patellar tendon rupture, follow the link below and answer a few short questions. Someone will get back to you as soon as possible. Thank you for choosing Summit Health. 

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