One of the most common and most important questions my patients ask when they come in with patellar instability is: Do I need surgery, or can I manage this without it?
In a recent issue of the American Journal of Sports Medicine (AJSM), a high-quality systematic review and meta-analysis directly addressed this question. (Article Link) The senior author was Justin Mistovich from University Hospitals in Cleveland. The authors analyzed randomized controlled trials comparing three treatment approaches:
Non-operative treatment
MPFL repair (an older surgical technique)
MPFL reconstruction (the modern surgical standard)
The differences were striking.
Non-operative treatment had a recurrent dislocation rate of a little over 30%.
MPFL repair reduced that risk to about 15%.
MPFL reconstruction lowered the recurrence rate to just 4%.
In other words, modern MPFL reconstruction reduces the risk of another dislocation from roughly one in three down to about one in twenty-five.
That difference matters. I have seen many patients who experienced several dislocations without major cartilage injury—until one particularly severe, unpredictable event caused significant cartilage damage. Once that happens, long-term outcomes can change dramatically.
Because of this, I now emphasize two key principles in my practice. First, I carefully evaluate each patient’s anatomic risk factors—such as patella alta, trochlear dysplasia, an elevated TT–TG distance, age, and other structural features—to estimate how likely recurrence is. Second, we use that information for shared decision-making, weighing the risk of recurrence against the risks and benefits of surgery.
Patellar instability should not simply be dismissed with a quick physical therapy prescription and no deeper discussion. The recurrence risk can be substantial, and modern surgical techniques are highly effective when appropriately indicated.
The second important question patients often ask—especially after undergoing surgery on one knee—is:
If this happened on one side, is it going to happen on the other? Should I consider doing something prophylactically?
Another study in the same AJSM issue, led by Chital Parikh at Cincinnati Children’s Hospital Medical Center, examined this exact issue. (Article Link) The authors reviewed all MPFL reconstructions performed at their institution between 2012 and 2022 to determine the likelihood of a contralateral (opposite-side) dislocation.
Patellofemoral instability is often related to how someone is built. Structural factors such as:
Patella alta
Trochlear dysplasia
Elevated TT–TG distance
Younger age
Female sex
all increase susceptibility to dislocation.
The findings were highly informative:
If a patient had none of these anatomic risk factors, the risk of dislocation in the opposite knee was less than 10%.
If a patient had all of these risk factors, the risk rose dramatically—approaching 80%.
That is an enormous difference.
For families, this data provides clarity. If the risk of the other knee dislocating is close to 80%, a discussion about prophylactic stabilization becomes very reasonable. If the risk is under 10%, surgery on the opposite side is likely unnecessary.
Taken together, these two studies reinforce an important message:
Patellar instability is not a one-size-fits-all condition. With careful evaluation of individual anatomy and evidence-based discussion of recurrence risk, we can make thoughtful, personalized decisions about whether surgery is appropriate—and when it may prevent significant long-term damage.