Description
Objectives: It is well known that meniscus extrusion caused by meniscus injury is associated with loss of meniscus function and knee osteoarthritis. Therefore, it is important for us to know the amount of meniscal extrusion after meniscus injury. However, few study investigated the amount of affected side meniscal extrusion based on the healthy side. Therefore, the purpose of this study was to compare the amount of lateral meniscal extrusion (LME) on the affected and healthy knee in the patients with isolated radial tear in the middle segment of lateral meniscus (RTMLM).
Methods: There were total 11 patients (10 males and 1 female, mean age 18±2.5 years) with RTMLM. For all patients, MRI scan of both affected and healthy knee was performed immediately after injury. LME was measured on mid-coronal plane of those MRI images. Actually, as LME, the distance between the outer edge of the articular cartilage of the tibial plateau and the outer edge of the lateral meniscus was measured on affected and healthy knee.
Results:
The mean LME on affected and healthy side were 2.7±1.1 mm and 1.7±0.75 mm, respectively, with significantly difference(p<0.05). Moreover, in each patient, LME on the affected side was always larger than that on the healthy side.
On the affected side, there were 5 (45.5%) patients with more than three millimeters of LME, while only one (9%) patient on the healthy side. There was also significantly difference (p<0.05).
Conclusion:
In the cases with radial tears of the lateral meniscus, the LME of the affected side was larger than that of the healthy side, and the LME of more than 3 mm was observed in about half of the cases. From these results, RTMLM can be a risk for loss of meniscus function. Therefore, depending the amount of LME, careful treatment should be performed to preserve meniscal function.
