Earlier magnetic resonance imaging-based diagnosis and prompt surgical consultation reduce medial meniscus extrusion following posterior root repair

Background To investigate factors influencing the change in medial meniscus extrusion (ΔMME) following pullout repair in patients with medial meniscus posterior root tears (MMPRT). Methods This study included 84 knees of patients with MMPRT who had a clearly defined date of injury and underwent pullout repair. Preoperative and 3-month postoperative magnetic resonance imaging (MRI) data were available for all patients. The association between the ΔMME (defined as the difference between the preoperative and 3-month postoperative medial meniscus extrusion [MME] values) and the following factors was analyzed: age, sex, body mass index, and the time from injury to MRI examination (Injury/MRI interval), consultation with knee surgeons (Injury/Consult interval), and surgery (Injury/Surg interval). Results The average durations were 20.5 days for the Injury/MRI interval, 33.1 days for the Injury/Consult interval, and 53.6 days for the Injury/Surg interval. The mean MME was 3.94 mm preoperatively and 4.51 mm at 3 months postoperatively. Univariate analysis showed that the Injury/MRI, Injury/Consult, and Injury/Surg intervals were significantly correlated with the ΔMME (all P < 0.001). A strong correlation was observed between the Injury/Consult and Injury/Surg intervals (correlation coefficient = 0.933). In the multivariate analysis, the Injury/MRI and Injury/Consult intervals remained significantly associated with the ΔMME (both P < 0.01). Conclusions Shortening the Injury/MRI and Injury/Consult intervals may help prevent the progression of MME following MMPRT pullout repair. Early MRI evaluation and prompt specialist consultation are recommended when MMPRT is suspected, particularly in patients presenting with posterior knee pain or a popping episode. Level of evidence Level IV.