Arthroscopic and open reconstruction of the posterolateral corner of the knee have equally good clinical results: first results of a prospective 12-month follow-up study.

Purpose: Arthroscopic reconstruction techniques for higher-grade posterolateral corner (PLC) injuries (Fanelli Type B, PoLIS LI-B) have not yet been validated in clinical studies. The open reconstruction technique described by Arciero is well-established and showed good restoration of joint stability in previous studies. This study aimed to compare clinical outcomes of this established open surgery technique to a newly developed arthroscopic technique in a prospective randomized clinical trial.

Methods: Between 2019 and 2021, this study focused on chronic high-grade PLC injuries (Fanelli Type B, PoLIS LI-B). Group A consisted of patients treated with conventional open surgery following Arciero's technique, while Group B included patients treated with Arciero's arthroscopic technique. All cases underwent additional PCL reconstruction. After a minimum 12-month follow-up, clinical scores and objective stability assessments were compared between the groups.

Results: In total, 26 (group A 12, group B 14) eligible patients with a mean follow-up of 14.9 ± 7.2 months were evaluated in the present study. Knee stability and patient-reported outcome scores (PROMS) were significantly improved when comparing pre- and post-operative values (p < 0.0001). No clinically relevant differences in PROMS (Lysholm: A 83.9 ± 11.4 vs. B 85.3 ± 13.8; IKDC: A 76.91 ± 12.6 vs. B 76.8 ± 15.7) were shown in both groups. Additionally, no statistically significant differences were detected between groups with respect to external rotation, range of motion and instrumental stability testing. Arthroscopic reconstruction showed significantly shorter operation time (p = 0.0109). There were no clinical failures or neurovascular complications of the surgical procedures.

Conclusion: Both surgical techniques for isolated chronic PLC Fanelli Type B injuries significantly improved the knee stability, were equivalent with respect to PROMs and led to good clinical results. However, arthroscopic PLC reconstruction was associated with a shorter surgery time compared to open PLC reconstruction. Therefore, arthroscopic PLC reconstruction may be a viable option in the hands of an experienced surgeon.

Level Of Evidence: Prospective cohort study, II.