Summary
Clinical outcomes after repair of lateral meniscus posterior root tears combined with ACL reconstruction are not inferior to isolated ACL reconstruction at two years follow-up.
Abstract
Introduction
Lateral meniscus posterior root tear (LMPRT) is often accompanied by anterior cruciate ligament (ACL) injury and increases both anterolateral rotatory instability and load on the articular cartilage. However, studies on the outcomes of LMPRT repair are scarce. Thus, we aimed to evaluate the clinical outcomes of LMPRT with ACL reconstruction (ACLR).
Methods
This study included 107 patients who underwent primary ACLR using autologous hamstring tendons and were followed up for 2 years. Twenty-five patients who underwent simultaneous LMPRT repair were classified into the LMPRT group, and 82 patients who underwent isolated ACLR without any meniscal procedures were classified into the isolated ACLR group. Both subjective and objective outcomes were measured before and 2 years after surgery, and subjective outcomes were also collected at 3 months and 1-year post-surgery. The clinical outcomes of the two groups were compared after adjusting for age, sex, body mass index (BMI), and pre-injury Tegner scale scores. Improvement in clinical outcomes was evaluated using repeated analysis of variance.
Results
After adjusting for all covariates, the preoperative pivot shift grade was higher in the LMPRT group than that in the ACLR group. Preoperative subjective outcomes were significantly poorer in the LMPRT group than those in the isolated ACLR group, except for the International Knee Documentation Committee score. At the 2-year follow-up, the Lysholm score in the LMPRT group was higher than that in the ACLR group. The LMPRT group exhibited a significantly greater improvement in subjective outcomes than that in the isolated ACLR group, except for the Knee Injury and Osteoarthritis Outcome Score Symptom subscale. Improvements in the objective measurements of the two groups were not significantly different. Although no significant difference was observed in the lateral meniscus extrusion (LME) width before and 1 year after surgery, LME width decreased by an average 0.2 mm in the LMPRT group.
Conclusion
Patients with concomitant LMPRT and ACL injury showed a greater pivot shift grade and poorer subjective outcomes than patients with isolated ACL preoperatively; however, the clinical outcome of ACLR with LMPRT was not inferior to that of isolated ACLR at 2 years postoperatively. Following LMPRT repair, the patients were able to restore knee joint stability and showed similar recovery levels as patients with isolated ACLR for at least a short period.