Patellofemoral stabilisation

The kneecap, or patella, normally glides up and down in a groove at the front of the thigh bone as the knee bends and straightens. Patellar instability occurs when the kneecap slides too far out of this groove, either partially (subluxation) or completely (dislocation), usually toward the outer side of the knee.

This is most often the result of an injury, such as a twisting movement or a direct blow during sport, but some people are more prone to it because of underlying anatomical factors like a shallow trochlear groove, looseness of the surrounding soft tissues, or the way the kneecap and leg are aligned.

After a first dislocation, the medial patellofemoral ligament (MPFL), the main soft tissue restraint holding the kneecap in place on the inner side, is almost always torn, and if it heals loosely or doesn't heal well, the risk of the kneecap dislocating again rises substantially.

Patellofemoral stabilisation surgery aims to restore normal tracking of the kneecap and reduce the risk of further dislocations. The core procedure is MPFL reconstruction, where a tendon graft, often taken from the patient's own hamstring, is used to recreate the torn ligament, anchoring the kneecap securely to the femur in a way that mimics its natural restraint. This is generally recommended after a second dislocation, or sometimes after a single dislocation if imaging shows a high risk of recurrence or if there is associated cartilage damage. In some patients, MPFL reconstruction alone doesn't fully correct the problem, particularly when the tibial tuberosity, the bony bump below the kneecap where the patellar tendon attaches, is positioned abnormally, contributing to abnormal kneecap tracking. In these selected cases, a tibial tuberosity transfer is performed alongside the ligament reconstruction, repositioning this bony attachment point to improve the overall alignment of the whole extensor mechanism.

Each surgery Liam does for patellofemoral instability is based on careful assessment of each patient's individual anatomy, including clinical assessment of a patients ligamentous laxity, rotational profile and specific measurements taken from CT or MRI scans that assess how far the tibial tuberosity sits relative to the groove it should align with.

This is discussed with each patient individually before surgery

Recovery typically involves an initial period of protected weight-bearing and limited range of motion to allow the graft and any bony work to heal, followed by a structured physiotherapy program that gradually restores movement, strength, and control around the knee. Return to sport is usually guided by physiotherapy milestones rather than a fixed timeline, and generally takes four to nine months depending on which procedures were performed and how the knee responds through rehabilitation.