Effect Of Meniscoplasty For Laterl Discoid Meniscus On The Axial Alignment Of The Lower Limb

Objective:To investigate the changes of arthroscopic meniscoplasty of the discoid lateral meniscus on the axial alignment of the lower limb,and evaluate the axial alignment of the lower limb in patients with discoid meniscus injury.Methods:From January 2017 to January 2019,a total of 42 patients were included in this study,included 17 males and 25 females.The age is between 17-52 years old.All these patients were diagnosed meniscus injury and could straighten their knee in standing position.All patients were diagnosed by arthroscopy,including normal meniscus of 11(group 1),lateral incompete discoid meniscus injury of 18(group 2)and lateral complete discoid meniscus injury of 13(group 3).Without meniscus tear and discoid meniscus was confirmed by arthroscopy in the group 1.The group 2 and 3 underwent arthroscopic meniscoplasty.The Full-length weight bearing X-rays were taken1-2 days before and after surgery.The tibio-femoral angle(TFA),mechanical axis deviation(MAD)was measured to evaluate the axial alignment of the lower limb.Results:The TFA and MAD both changed significantly after operation in the group2 and group 3,and the difference was significantlystatistically,P<0.001.There were no significant difference in the absolute value of the TFA and MAD before and after surgery between the group 2 and group 3,P>0.05.The TFA and MAD before operation in the group 2 and group3 were lager than those in the group 1,and the difference was significantly statistically,P<0.05.Conclusion:The axial alignment of the lower limb in patients with a torn discoid laterl meniscus was altered instantly after arthroscopy meniscoplasty.The postoperative varus is reduced,and some patients showed valgus.The axial alignment of the lower limb was mild varus in patients with discoid laterl meniscus injury.For patients with discoid meniscus in clinical work,the evalation of the axial alignment of the lower limb should be strengthened.In order to restore the axial alignment of the lower limb or protect the knee function after surgery,the principle of individualized treatment can be taken.