Complete medial meniscal root injury and medial collateral ligament injury are risk factors for increased medial meniscal extrusion
DC Astur, M CohenObjectives
To evaluate the association between medial meniscus posterior root tear (MMRT) with anthropometric characteristics of the patient (age, weight, and height) and associated injuries identified on MRI (meniscal extrusion, medial collateral ligament [MCL] injury, bone edema, and subchondral fracture of the tibia).
Methods
The characteristics and associated injuries of 55 patients diagnosed with an injury (either partial or complete) of the root of the posterior horn of the medial meniscus, diagnosed on MRI and confirmed arthroscopically, were compared. Specifically, age, sex, anthropometric data, meniscal extrusion, associated MCL injury, and presence of associated bone edema were evaluated.
Results
There was a moderate positive correlation between the age of the patients and the degree of extrusion (r = 0.565; p < 0.0001). Greater meniscal extrusion was observed in patients who had complete medial meniscus root tear (C-MMRT) (p = 0.008). Patients with MCL injury presented with significantly greater meniscal extrusion when compared to individuals without MCL injury (p = 0.042). Similarly, the incidence of bone bruising was higher in patients with a MMRT with an associated MCL injury, when compared to patients without concomitant MCL injury (p=0.012).
Conclusion
Patients with a C-MMRT had greater meniscal extrusion than patients with a partial medial meniscus root tear (P-MMRT). The presence of a concomitant MCL injury was significantly associated with the meniscal extrusion in patients with concomitant meniscal root injury. The presence of associated bony edema was not associated with meniscal extrusion, but was significantly more common in patients with C-MMRT when there was an associated MCL injury compared to those without an associated MCL injury.