Medial Patellofemoral Ligament (MPFL) Reconstruction

The kneecap or the patella and the trochlear groove are important parts of the knee that work together to straighten and bend the knee.

The kneecap is a small, triangular bone located at the front of the knee where the thighbone and shinbone meet. It plays a vital role in protecting the knee joint and connects the thigh muscles to the shinbone, allowing you to straighten your knee.

The trochlear groove, also known as the patellofemoral groove, is a shallow V-shaped channel situated at the lower end of the thighbone (femur). This groove accommodates the kneecap (patella) and provides a track for it to glide smoothly as the knee bends and straightens.

When the knee is bent and straightened, the kneecap moves up and down within the trochlear groove. Movement of the kneecap is guided by the groove’s shape and the surrounding ligaments, ensuring that the kneecap stays in place. If the groove is too shallow or if the ligaments are damaged, the kneecap may move out of its track, causing pain or instability.

The medial patellofemoral ligament is a critical ligament located on the inner side of the knee that keeps the kneecap in its grove and prevents it from dislocating. Injuries to the medial patellofemoral ligament can be caused by a forceful blow to the knee, a fall or a sports injury.

When the medial patellofemoral ligament is torn, usually due to a dislocation, the patella can become unstable, leading to recurrent dislocations and knee pain. The vast majority of  dislocations result in injury of the medial patellofemoral ligament.

Medial patellofemoral ligament reconstruction is a surgical procedure aimed at treating recurrent patellar (kneecap) dislocations. The goal of medial patellofemoral ligament reconstruction is to replace the damaged ligament and stabilize the kneecap. The procedure involves using a tendon graft (either from the patient or a donor) to create a new ligament. Dr. Kaplan will make small incisions around the knee, drill tiny holes in the kneecap and thigh bone, and anchor the graft to these bones, restoring stability to the kneecap. This helps prevent future dislocations and improves knee function.

Medial patellofemoral ligament reconstruction is typically recommended for patients who have experienced multiple knee cap dislocations, particularly when conservative treatments like physical therapy, bracing, and activity modification have not been successful. It is also considered when there is a significant tear in the medial patellofemoral ligament or when anatomical factors, such as a shallow trochlear groove or a high-riding patella (patella alta), contribute to instability.

Recovery from MPFL reconstruction surgery typically involves a combination of rest, bracing, and physical therapy. In the first few weeks, a knee brace is used to protect the knee. If an MPFL is performed without additional procedures, patients are allowed to bear weight on the operative limb immediately (while in the brace). Physical therapy begins early to reduce swelling, restore range of motion, and gradually strengthen the surrounding muscles. Over the next few months, exercises focus on improving strength and stability in the knee, with a gradual return to normal activities. Most patients can resume light activities after 3 months, while full recovery, including a return to sports, may take 6 to 12 months.