Patellar and Quadriceps Tears
Tendons are made up of strong fibrous tissue that connect muscle to bone. In the knee, the quadriceps and patellar tendons work together with the muscles in the front of your thigh (quadriceps muscles) to straighten or extend the knee.
The four quadriceps muscles meet just above the kneecap (patella) to form the quadriceps tendon. The quadriceps tendon attaches the quadriceps muscles to the patella. The patellar tendon attaches the bottom of the kneecap (patella) to the top of the shinbone (tibia). It is actually a ligament that connects to two different bones, the patella and the tibia. The quadriceps and patellar tendon work together to help straighten the knee.
Most commonly, a tear in the quadriceps or patellar tendon occurs via injury. Jumping or landing awkwardly, where there is a great deal of force on the leg can cause a tendon tear. A direct fall onto the front of the knee can also cause these types of tears. A weak tendon is more likely to tear. Weakening of tendons can be caused by:
- Tendinitis – Inflammation of the quadriceps tendon, called quadriceps tendinitis, weakens the tendon. It may also cause small tears. Quadriceps and patellar tendinitis is most common in runners or people that engage in sports that require a lot of jumping such as basketball.
- Chronic disease – Weakened tendons can also be caused by chronic illnesses such as:
- Chronic renal failure
- Rheumatoid arthritis
- Systemic lupus erythematosus (SLE)
- Diabetes mellitus
- Metabolic disease
- Steroid use – Using corticosteroids has been linked to increased muscle and tendon weakness. Use of corticosteroids near the patellar tendon specifically has shown increased instances of tendon rupture.
- Antibiotics – certain antibiotics, specifically Fluoroquinolones, have been associated with tendon tears.
Quadriceps and patellar tendon tears may be partial or complete tears. Often people experience a popping or tearing sensation along the front of the knee. Other symptoms include:
- Deformity – for quadriceps tendon tears an indentation along the top of the knee cap may be noticeable. For patellar tendon tears this indentation is often towards the bottom of the kneecap.
- Kneecap position – In quadriceps tendon tears you may notice that the kneecap sags or droops. In the case of patellar tendon tears, the kneecap may move higher towards the thigh because it is no longer anchored to the tibia
- Weakness or inability to straighten the leg
To identify a quadriceps tendon tear Dr. Faucett will ask about your medical history and perform a thorough physical examination of your knee. Some imaging tests, such as an X-ray or MRI scan may be ordered to confirm the diagnosis. X-rays of the knee is taken to know the position of the kneecap and MRI scan to know the extent and location of the tear. Ultrasound is also used in an acute setting to identify a patellar or quadriceps tendon tear.
Small or partial tears for both quadriceps and patellar tendon tears can often be managed with non-operative treatment. Non operative treatment includes:
- Immobilization- wearing a knee brace to prevent movement of the knee to allow the tear to heal. You will likely need crutches to avoid putting weight on the leg
- Physical therapy- is often recommended to help regain range of motion and strengthen the muscles around the knee joint.
Most patients with complete tears will require surgical repair to restore function. For both patellar and quadricep tendon tears, surgery is performed on an outpatient basis cannot be repaired arthroscopically since the tendon is outside the joint.
Quadriceps tendon repair involves re-attaching the torn tendon to kneecap. Sutures are placed in the torn tendon which is then passed through the holes drilled in the knee cap. The sutures are tied at the bottom of the knee cap to pull the torn edge of the tendon back to its normal position.
For a patellar tendon tear, the goal is to also reattach the tendon to the kneecap to restore function. To reattach the tendon, sutures are placed in the tendon and then threaded through drill holes in the kneecap. The sutures are tied at the top of the kneecap. The sutures are tied to get the correct tension in the tendon to restore the position of the kneecap.
Following surgery for both Quadriceps and Patellar tendon repairs, you will be in a knee brace to immobilize the knee. You will also require crutches to avoid weight bearing on the leg. Physical therapy is an important part of the post operative recovery and is required for several months to help restore motion and strength.
The most common surgical complications include weakness and loss of motion. Re-tears sometimes occur, and the repaired tendon can detach from the kneecap. In addition, the position of your kneecap may be different after the procedure. As with any surgical procedure, there is also a risk of other complications including infection, bleeding, blood clot, or nerve injury.