Functional, Magnetic Resonance Imaging, and Second-Look Arthroscopic Outcomes After Pullout Repair for Avulsion Tears of the Posterior Lateral Meniscus Root

Abstract

Background: Little data exist in the literature regarding second-look arthroscopic outcomes after pullout repair for avulsion tears of the posterior lateral meniscus root.

Purpose: To (1) assess the functional, magnetic resonance imaging (MRI), and second-look arthroscopic outcomes after pullout repair for avulsion tears of the posterior lateral meniscus root; (2) determine which demographic and clinical factors influenced healing of the repaired posterior lateral meniscus root; and (3) compare outcomes between different meniscal healing status groups.

Study design: Case series; Level of evidence, 4.

Methods: A total of 31 patients underwent pullout repair for avulsion tears of the posterior lateral meniscus root and had a minimum 2-year follow-up. Functional outcomes were assessed using patient-reported scores (Lysholm, Tegner, and International Knee Documentation Committee [IKDC] scores). Lateral meniscal extrusion, cartilage degeneration of the lateral compartment, and healing of the repaired posterior lateral meniscus root were assessed via MRI. The healing status was also assessed using second-look arthroscopic surgery, and the patients were divided into different healing status groups.

Results: The postoperative patient-reported scores improved significantly compared with the preoperative values (P = .001). Lateral meniscal extrusion was reduced significantly from 3.37 ± 0.82 mm preoperatively to 0.63 ± 0.80 mm at final follow-up (P = .001). The grade of cartilage degeneration of the lateral compartment progressed from 0.69 ± 0.67 preoperatively to 0.95 ± 0.83 at final follow-up (P = .213). MRI scans showed complete healing in 28 patients (90.3%) and partial healing in 3 patients (9.7%). Second-look arthroscopic surgery showed stable healing in 18 of 23 patients (78.3%) and lax healing in 5 of 23 patients (21.7%). Patients with stable healing had significantly higher Lysholm and IKDC scores, more reduction of meniscal extrusion, and less progression of cartilage degeneration than did patients with lax healing (P < .05). Concomitant anterior cruciate ligament reconstruction was found to significantly positively influence healing of the repaired posterior lateral meniscus root (P = .047).

Conclusion: Pullout repair for avulsion tears of the posterior lateral meniscus root yielded significantly improved patient-reported scores, reduced meniscal extrusion, and a satisfactory healing rate at final follow-up. Patients with stable healing had significantly better functional and MRI outcomes than did patients with lax healing.

Keywords: lateral meniscus; pullout; repair; root; tears.