Summary

LM radial tear in a stable knee

Abstract

Introduction

Meniscal repair is essential for radial tear of lateral meniscus midbody (RT-LMMB) to restore the hoop tension of the meniscus in younger patients. However, a paucity of evidence exists regarding the results of meniscal repair for this specific tear of lesion particularly in a stable knee. Therefore, the current study aimed to report the clinical outcomes of arthroscopic all-inside repair using absorbable sutures for RT-LMMB in a stable knee. Furthermore, we aimed to determine the risk factors for failure or incomplete healing after the meniscal repair.

Material: From August 2011 to August 2022, 44 consecutive patients who had all-inside repair using absorbable sutures for RT-LMMB in a stable knee were retrospectively reviewed across two institutions. Patients with pre- and postoperative magnetic resonance imaging (MRI) and at least 24 months of follow-up were enrolled. Radiologically, the lateral meniscal extrusion and healing status were evaluated through preoperative and postoperative MRI at 6 months. Clinically, preoperative and postoperative patient-reported outcomes measures (PROMs) were evaluated using the Tegner activity scale, Lysholm, and IKDC subjective scores. Failure was defined as revision surgery for the recurrence of symptoms. Subgroup analyses were performed to determine the risk factors for failure or incomplete healing after the meniscal repair.

Results

Of 44 patients, 37 were finally included with a mean age of 25.8 ± 9.8 years (range, 11 to 55 years). The mean follow-up was 37.8 ± 26.5 months (range, 24 to 147 months). Radiologically, no significant progression of lateral meniscal extrusion was found and the rate of meniscal healing on MRI was reported at 73.0%. Clinically, significant improvements in all PROMs were found between preoperative and postoperative assessments at the latest follow-up. Failure was found in one patient (2.7%) requiring meniscal allograft transplantation due to the aggravation of symptoms and resorption of the lateral meniscus at 4 years of follow-up. Logistic regression analysis revealed that discoid morphology of lateral meniscus (DLM) was a significant factor for incomplete healing on MRI after the surgery.

Conclusion

Arthroscopic all-inside repair using absorbable provides excellent clinical and radiologic results for RT-LMMB in a stable knee with a minimum follow-up of 2 years. DLM is a risk factor for incomplete healing, as shown on postoperative MRI, although it was not associated with definite failure.