All-inside lateral meniscus posterior root repair: comparing scorpion and suture device with clinical, MRI-based, and finite element analysis

This study aims to compare the efficacy of Scorpion-based versus all-inside suture device techniques for repairing lateral meniscus posterior root tears based on clinical, radiographic, and finite element analysis findings. A retrospective analysis included 98 patients (Scorpion group: n =51; suture device group: n =47) who underwent surgery between 2016 and 2022. Outcomes were assessed via knee function scores, stability tests (Lachman, anterior drawer, pivot shift), MRI (meniscal integrity at 1 year, MOAKS), and finite element analysis of stress/strain under load. Among the 98 included patients, both the Scorpion and suture device groups demonstrated significant improvements in subjective functional scores from preoperative to postoperative assessments. No significant differences were observed in subjective functional scores between the two groups. However, the Scorpion group demonstrated less postoperative meniscal extrusion (1.68 vs. 2.21 mm, P = 0.038), a greater postoperative reduction in anterior displacement of the lateral tibial plateau (1.25 vs. 0.62 mm, P < 0.001), and lower MOAKS scores (13.31 vs. 15.92, P < 0.001). Finite element analysis also indicated better displacement control and stress distribution in the Scorpion group. Both techniques improved postoperative knee stability and functional scores, with no significant early clinical differences. However, the Scorpion technique was associated with more favorable MRI and biomechanical findings at the 1-year follow-up, which could be interpreted as preliminary evidence supporting the Scorpion technique as a viable alternative.