Anatomic medial patellofemoral ligament reconstruction using patellar suture anchor fixation for recurrent patellar instability

Purpose

The purpose of this study was to prospectively evaluate clinical and radiographic outcomes following anatomic medial patellofemoral ligament (MPFL) reconstruction using patellar suture anchor fixation for recurrent patellar instability.

Methods

Twenty patients (20 knees) were enrolled in this study. The median age was 21 years, and the median follow-up was 34.5 months. Reconstruction was performed using a hamstring autograft fixed with two suture anchors at native patellar site of the MPFL. No patient had undergone additional medial tibial tuberosity transfer. Clinical scores (Kujala, Lysholm, and Tegner score) and apprehension test were completed preoperatively and at the follow-up. Preoperative and follow-up radiographic assessments included modified Insall-Salvati ratio, congruence angle, and lateral patellofemoral angle.

Results

The preoperative Kujala and Lysholm scores were 52.6 ± 12.4 and 49.2 ± 10.7, and at follow-up visits, corresponding values were 90.9 ± 4.5 (p < 0.001) and 90.9 ± 5.2 (p < 0.001). Tegner score increased from 3.0 (range 1–4) to 5.0 (range 4–7) (p < 0.001). The apprehension test was positive in all patients preoperatively, but only positive in one patient at follow-up. All radiographic assessments were significantly improved; modified Insall-Salvati index (from 1.75 to 1.65) (p = 0.002), congruence angle (from 6.3° to ?7.0°) (p < 0.001), and lateral patellofemoral angle (from 2.1° to 4.9°) (p = 0.008). No patient experienced a patellar fracture or redislocation.

Conclusion

These results are comparable to those of bone tunnel techniques reported in the literature. This study shows that anatomic MPFL reconstruction using two suture anchors is a reliable treatment option.

Level of evidence

Case series with no comparison group, Level IV.