Outcomes of an anatomic posterolateral knee reconstruction.

BACKGROUND Chronic posterolateral knee injuries often result in substantial patient morbidity and functional instability. The clinical stability and functional outcomes following anatomic reconstructions in patients with a chronic posterolateral knee injury have not been determined, to our knowledge. METHODS A two-center outcomes study of sixty-four patients with grade-3 chronic posterolateral instability was performed. The patients were evaluated subjectively with the modified Cincinnati and International Knee Documentation Committee (IKDC) subjective scores and objectively with the IKDC objective score. RESULTS Eighteen patients had an isolated posterolateral knee reconstruction, and forty-six patients underwent a single-stage multiple-ligament reconstruction that included reconstruction of one or both cruciate ligaments along with the posterolateral knee reconstruction. The average duration of follow-up was 4.3 years. The fifty-four patients who were available for follow-up had an average total Cincinnati score of 65.7 points. A significant improvement was found between the preoperative and postoperative IKDC objective scores for varus opening at 20 degrees, external rotation at 30 degrees, reverse pivot shift, and single-leg hop. CONCLUSIONS An anatomic posterolateral reconstruction resulted in improved clinical outcomes and objective stability for patients with a grade-3 posterolateral knee injury.