The quadriceps are the large group of muscles in the front of the thigh. They consist of four muscles in each leg that run from the hips to the knees. Tendons are cords of strong fibrous tissue that attach muscle to bone. If a tendon tears, the muscle will no longer work properly. The quadriceps tendon attaches the quadriceps muscles to the patella, or kneecap, and helps straighten the leg. If the quadriceps tendon gets a small tear, walking and other activities become more difficult. A large tear is disabling and usually requires surgery to reattach the tendon and physical therapy to strengthen the muscles and improve function.
Quadriceps tears are fairly uncommon, but certain factors increase the risk:
- Being over 40
- Being an active runner or playing jumping sports, like basketball
Types of Quadriceps Tears
According to the American Academy of Orthopaedic Surgeons (AAOS), quadriceps tendon tears can be either partial or complete.
- Partial Tears: Many tears do not completely disrupt the soft tissue. This is similar to a rope stretched so far that some of the fibers are frayed, but the rope is still in one piece.
- Complete Tears: A complete tear will split the soft tissue into two pieces. When the quadriceps tendon completely tears, the muscle is no longer anchored to the kneecap. Without this attachment, the knee cannot straighten when the quadriceps muscles contract.
Causes of Quadriceps Tendon Tears
Quadriceps tendon tears most often occur as a result of injury, joint weakness, or a chronic condition. Injury can occur when a heavy load is placed on the leg when the knee is partially bent, such as when a basketball player lands awkwardly after jumping, and the resulting force causes the tendon to tear. Other injuries that can cause a tendon tear include falls, a blow to the front of the knee, or a deep cut also can cause a tear.
In addition to injury, overall tendon weakness or a chronic disease can be causes of tears. Weakness resulting from tendonitis, or inflammation of the tendon, often is seen in athletes who run and/or jump a lot. In addition, lack of movement for prolonged periods of time can weaken muscles and tendons and cause a loss of strength and flexibility. The AAOS also cites chronic diseases that disrupt blood supply to the tendons and weakens them. These include:
- Chronic renal failure
- Conditions associated with renal dialysis
- Rheumatoid arthritis
- Systemic lupus erythematosus (SLE)
- Diabetes mellitus
- Metabolic disease
Lastly, the use of corticosteroids is linked to increased muscle and tendon weakness.
When a quadriceps tendon tears, there is often a tearing or popping sensation. Pain and swelling usually follow, and it may not be possible to straighten your knee. Additional symptoms include:
- An indentation at the top of the kneecap where the tendon tore
- A sagging or drooping kneecap where the tendon is torn
- Difficulty walking due to the knee buckling or giving way
Prior to the procedure your doctor will ask about your medical history, including any prior injury to the affected joint, and perform a physical exam Additional tests may include:
- MRI scan
Treatment options will depend on the severity of the tear, and may be nonsurgical or surgical. Your doctor will plan your treatment based on the type and size of the tear, your activity level, and your age.
If the quadriceps tendon tear is small, nonsurgical treatment will likely be tried first, usually with good results. Typically this includes wearing a brace and working with a physical therapist to safely strengthen the quadriceps muscles.
A knee immobilizer or brace may be recommended for 3 to 6 weeks to help keep your leg straight while the torn tendon heals. You will likely need crutches to avoid putting all of your weight on your leg.
Once the initial pain and swelling subsides, physical therapy can begin. Exercises will be added gradually, with the goal of increasing strength and range of motion. As the tear heals and the muscles get stronger, your brace may be removed and you will be given exercises to do at home. Always consult your doctor about when it is safe to return to playing sports.
If the quadriceps tendon tear is severe, you will require surgery to repair the torn tendon and reattach it to the kneecap. The sooner surgery is performed after an injury, the better the outcome will be. Early repair also keeps the tendon from scarring and tightening when in a shortened position.
- Hospital Stay: Tendon repair surgery is sometimes performed on an outpatient basis, but more often takes place in a hospital and may include an overnight stay. The surgery may be performed with regional (spinal) anesthesia to numb the lower body, or with a general anesthetic to put you to sleep.
- Recovery and Rehabilitation: Your doctor’s rehabilitation program for physical therapy and other exercises will depend on the type of tear, the type of surgical repair, and any other medical conditions you may have. After surgery you will require pain management medications and ice. Your surgeon will remove sutures or staples about two weeks after surgery. Complete recovery takes at least 4 months, but most repairs are almost completely healed within 6 months. It may take even longer to completely achieve strength training and range of motion goals.
Problems from the procedure are rare, but all procedures have some risk. Your doctor will review potential problems like:
- Loss of Motion or stiffness in the joint
- Formation of scar tissue that interferes with normal tendon movement
- Re-rupture of the injury
If your age is 60 years or older, it may increase risk of complications. Other factors include:
- Poor overall health
- Use of certain medications
When to Contact Your Doctor Post Procedure
Contact your doctor if your recovery from quadriceps tendon tear surgery is not progressing as expected or you develop complications, such as:
- Signs of infection, including fever and chills.
- Redness, swelling, increasing pain, excessive bleeding, or discharge from the incision site.
- Pains that you cannot control with the medications you have been given.
- Your brace is broken or not functioning properly.
- Skin below the cast becomes cold, discolored, numb, or tingly.
- New or worsening symptoms.
American Academy of Orthopaedic Surgeons: www.aaos.org
If you suspect you have a quadriceps tendon tear, please consult your healthcare provider.