Available online 24 November 2023, 151033

Author links open overlay panel, ABSTRACT

Medial patellofemoral ligament (MPFL) repair is a historically relevant treatment option for patellar instability, though it has been increasingly supplanted by MPFL reconstruction. Although several comparative studies report superior functional outcomes and a lower risk of recurrent patellar dislocation after MPFL reconstruction, MPFL repair may still be a viable treatment for a select group of patients. Patients with normal trochlear morphology, a normal TT-TG distance, lack of patella alta, and older age may be the best candidates for MPFL repair. MPFL repair also appears to be most effective when performed in the acute setting for avulsion-type tears. In an effort to improve repair outcomes, suture tape augmentation of MPFL repair has emerged recently and has shown promising early results. While our practice is typically to perform MPFL reconstruction for patellar instability, MPFL repair in appropriately selected patients may provide good clinical outcomes while avoiding some of the risks associated with reconstruction.

Section snippetsINTRODUCTION

First-time patellar dislocations commonly occur in young, active individuals and may lead to recurrent patellar instability in up to 60% of patients (1). Several patient factors have been associated with an increased risk of patellar instability, including patella alta, trochlear dysplasia, increased tibial tuberosity-trochlear groove (TT-TG) distance, and younger age (2). Dislocations usually occur laterally and are almost always associated with disruption of the medial patellofemoral ligament

COMPARING MPFL REPAIR VERSUS RECONSTRUCTION

The literature comparing MPFL repair to reconstruction continues to grow but is of overall mixed quality. Many studies are hampered by differences in operative technique utilized within the same treatment group, variability in concomitant procedures performed, small sample sizes, and inclusion of patients with varied patterns of MPFL injury. Acknowledging these limitations, the data directly comparing these techniques suggest that outcomes after MPFL repair are at best equivalent but may be

WHAT FACTORS PREDICT MPFL REPAIR SUCCESS OR FAILURE?

Several patient-, treatment-, and injury-related factors have been associated with MPFL repair failure or success in the literature. Those associated with MPFL repair failure include patella alta, delay to surgical treatment of the tear, younger age, and uncorrected anatomic factors that predispose patients to dislocation (11,16, 17, 18, 19, 20, 21). On the other hand, factors associated with good outcomes after repair may include shorter time to repair after injury, avulsion tear morphology,

Suture Tape Augmentation

Given the shortcomings of MPFL repair outcomes, particularly when compared to the success of MPFL reconstruction, repair augmentation with suture tape has emerged as a recent innovation in patellar stabilization surgery. The goal of these techniques is to add an additional stabilizer to lateral translation of the patella, protecting the MPFL and allowing it to heal. Hopper and colleagues described a method of MPFL repair augmentation using 2mm, ultra-high molecular weight polyethylene suture

PREFERRED TECHNIQUE

While we favor MPFL reconstruction for most patients with patellar instability, MPFL repair may be considered as a treatment option in certain scenarios. In lower-demand, older patients with an acute avulsion-type tear, repair soon after injury could be a viable strategy. The ideal patient for repair would also have no trochlear dysplasia, a normal TT-TG distance, and a normal CDI, with complete visualization of the tear on preoperative imaging. While MPFL reconstruction could certainly be a

CONCLUSION

Operative strategies for patellar instability have trended away from MPFL repair in favor of MPFL reconstruction, as MPFL reconstruction provides excellent patient-reported outcomes along with low rates of recurrent instability. With careful patient selection and attention to co-existing pathology, MPFL repair may still be an option to achieve similar results. MPFL repair augmented with suture tape may offer an improvement on traditional repair techniques, though further research is needed to

Declaration of Competing Interest

No conflict.

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