Second-Look Arthroscopic Findings After Repairs of Posterior Root Tears of the Medial Meniscus

Background: A posterior root tear of the medial meniscus disrupts hoop tension and causes extrusion of the meniscus, which results in progressive cartilage degeneration. Purpose: To identify the structural integrity of healing after arthroscopic repair of a posterior root tear of the medial meniscus by second-look arthroscopy and to determine the clinical relevance of the findings. Study Design: Case series; Level of evidence, 4. Methods: From December 2006 to August 2008, 21 consecutive patients underwent arthroscopic pullout suture repair for a posterior root tear of the medial meniscus. Eleven were available for second-look arthroscopy evaluation (mean, 13.4 months; range, 10 to 22 months). The healing status of the repaired meniscus was classified as complete healing, lax healing, scar tissue healing, and failed healing. Chondral lesions were reviewed using arthroscopic photographs, and clinical evaluation was based on the Lysholm knee scores and the Hospital for Special Surgery scores. Results: There was no case with complete healing. Five knees had lax healing (symptomatic in 2 and asymptomatic in 3); 4, scar tissue healing (asymptomatic in all 4); and 2, failed healing (symptomatic in 1 and asymptomatic in 1). Progression of the chondral lesion was found in 1 case. Mean Lysholm scores improved from 56.1 preoperatively (range, 41 to 71) to 83.0 at follow-up (range, 69 to 91; P = .003); mean Hospital for Special Surgery score also significantly increased, from 64.1 (range, 50 to 76) to 87.4 (range, 77 to 95; P = .003). Conclusion: Complete healing was not observed in this retrospective case series of posterior horn meniscus repairs performed by 2 surgeons using a single technique. Further research is needed to clarify why all patients showed clinical improvement despite findings of incomplete or failed healing on second-look arthroscopy. Treatment modalities for managing posterior root tears of the medial meniscus require further investigation to determine their efficacy.