Patella Dislocation and Instability

A: No, and this distinction matters. A lateral release is an older technique where the tight lateral tissue is simply cut through — it provides slack, but at the cost of completely destroying the lateral support structure. In some cases this actually causes the patella to shift too far medially, creating a new instability problem. Lateral lengthening, which I use instead, divides and then repairs the tissue in a lengthened position. It achieves the same goal — centering the patella — without eliminating the lateral support entirely. If you’ve been told you need a lateral release, it’s worth asking if a lengthening procedure would be appropriate instead.

A: Yes, revision patella stabilization surgery is possible, and it’s something I do. Failed MPFL reconstruction is usually not just a graft problem — it almost always means that one or more of the underlying anatomical risk factors wasn’t addressed the first time. Before considering a revision, I want a complete workup: new imaging to measure the TT-TG distance, assess for trochlear dysplasia, evaluate patellar height, and understand what was done previously and how. A revision without that analysis is likely to fail again. Done with the right plan, revision surgery can be very effective.

A: Yes, and this is one of the reasons I take recurrent instability seriously. Every time the patella dislocates, it impacts the lateral edge of the femur and the inner surface of the kneecap — those impacts damage cartilage. Over time, repeated damage accumulates. Patients with chronic untreated instability have significantly higher rates of patellofemoral arthritis at a young age. Stabilizing the joint doesn’t just prevent the next dislocation — it protects the cartilage for the long term.

A: At that age with multiple dislocations, the statistical risk of ongoing instability is very high — potentially greater than 80% without surgical intervention, depending on the underlying anatomy. Young athletes with multiple risk factors often do not do well with physical therapy alone. I would want to see their MRI and full X-ray workup to evaluate the specific anatomy before making a recommendation, but in my experience, waiting for a third or fourth dislocation in this scenario often means more damage to the cartilage and a more complex surgical situation down the road. The earlier we address the underlying factors, the better the long-term joint health.

A: The tibial tubercle is the bump on your shin where the patellar tendon attaches. If it’s positioned too far to the outside, the entire pull of the extensor mechanism is shifted laterally, which increases the force pushing the patella out of the groove even during normal walking and bending. A tibial tubercle osteotomy (TTO) involves cutting a small segment of bone there and moving it to a better position — inward to correct the alignment, downward if the kneecap sits too high. It’s secured with screws, and the bone heals over the following months. It’s a more involved procedure than soft tissue surgery, but when the anatomy calls for it, skipping it often leads to failure.

A: The trochlea is the groove at the bottom of the femur where the kneecap sits. In most people it has a nice V-shaped channel that helps contain the patella. Trochlear dysplasia means that groove is too shallow, flat, or even convex — essentially, there’s no groove to sit in. It’s a significant risk factor because it means the knee is relying almost entirely on the MPFL to hold the patella in place. When we reconstruct the MPFL in a patient with severe dysplasia, we may also need to consider reshaping the groove itself (trochleoplasty) so the reconstruction has a better chance of success.

A: The MPFL — medial patellofemoral ligament — is the primary passive restraint that keeps your kneecap from sliding laterally out of the groove. Think of it as the check-rein. When the patella dislocates to the outside, it puts tremendous force across the MPFL, and it almost always tears in the process. This is why recurrent instability is so common after a dislocation — once the check-rein is gone, the knee relies more heavily on the bony anatomy and muscle activation to stay stable, and those aren’t always enough.

A: A dislocation usually has a pretty distinct presentation: a sudden buckling or rotating sensation, often a visible or palpable shift of the kneecap to the outside of the knee, rapid swelling, and significant pain. Sometimes it reduces on its own before you even see a doctor. A sprain tends to feel more like diffuse pain or tenderness without that sense of something moving dramatically out of place. If you felt the knee buckle or shift and now have significant swelling, get an MRI — it will tell us definitively what happened.

A: Not necessarily — and for most first-time dislocators, the initial treatment is non-operative. But the answer depends on a few important things: whether there is a loose piece of cartilage or bone in the joint that needs to be addressed, and how your anatomy looks on MRI and X-ray. Some patients have a combination of risk factors that make another dislocation highly likely, and in those cases, we may discuss surgery earlier than usual. Get an MRI and see someone soon so we can look at the full picture.