Quadriceps Tendon Rupture

The quadriceps tendon is a fibrous connection that links the large muscles in front of the thigh (quadriceps) and the knee cap (patella).  The quadriceps tendon works together with the quadriceps muscles to straighten the knee. The quadriceps muscles are the four muscles located in front of the thigh.

Quadriceps tendon rupture most commonly occurs in middle-aged people who participate in sports which involve jumping and running.  Quadriceps rupture may be caused by fall, direct blow to the leg or hard impact after jumping.  Chronic conditions can also lead to quad rupture such as tendinitis (inflammation of quadriceps tendon), rheumatoid arthritis, diabetes mellitus, infection, and chronic renal failure which weakens the quadriceps tendon.  Use of medications such as steroids and some antibiotics also weakens the quadriceps tendon.

When the quadriceps tendon tears, the patella may lose its anchoring support in the thigh.  You may be unable to straighten your knee and when standing lose the ability to keep the knee straight.  Patient’s describe the knee buckling on itself.

To identify quadriceps tendon rupture, Dr. Fischer will take a focused history and perform a physical examination of your knee.  Some imaging tests, such as an X-ray or MRI may be ordered to confirm the diagnosis.  X-ray of the knee is taken to reveal the position of the kneecap and MRI scan to know the extent and pattern of the tear.

Quadriceps tendon rupture can be treated by non-surgical and surgical methods. Non-surgical treatment involves use of knee braces to immobilize the knee. Crutches or a walker are often needed to assist with mobilization.  Physical therapy will be recommended to restore strength and range of motion of the knee.

Surgery is performed when the injury is unlikely to heal adequately on its own and to facilitate a more rapid return to activity.  The goals of surgery are to re-attach the torn tendon to the kneecap and restore the normal kinematic function of the knee.  Sutures are placed in the torn tendon which is then passed through holes drilled in the kneecap. The sutures are tied at the bottom of the patella to pull the torn edge of the tendon back to its normal position.

Even with a well performed surgery, patients may experience persistent weakness and loss of motion, particularly knee extension.  Following your rehabilitation guidelines is important to ensure a complete recovery and prevent reinjury.

Following surgery, a knee brace or cast is placed to protect the healing tendon.  Complete healing of the tendon will take 3-6 months.