Arthroscopy assisted partial meniscectomy and repair for torn discoid lateral meniscus.

[Objective]To observe the necessity and outcome of arthroscopic partial resection and marginal repair for discoid lateral meniscus tear.[Method]From January 2006 to June 2009,32 patients with torn discoid lateral meniscus were treated,including 13 males and 19 females,with an average age of 27 years(15 to 51 years).All cases complained pain on the lateral side of injured knee,and were confirmed as discoid lateral meniscus injury by positive McMurry test,MR image,and arthroscopic observation.After meniscal plasty by resection of injured central part,marginal repair was completed by outside-in or all-inside technique.Twenty-seven patients were followed up for an average of 17 months(13 to 22 months),and were evaluated by Lysholm knee score at the last follow-up.[Result](1) In this group,there were tears in central white zone in all 32 cases,and marginal tears at anterior horn in 23 cases,at body in 19 cases,and at posterior horn in 8 cases.(2) The symptoms were relieved in all 27 followed up patients,in whom the McMurry test was negative postoperatively.(3) At the last follow-up,the average Lysholm knee score improved from 47(range,32-65) to 88(range,72-98).[Conclusion]The marginal tear was common in injured discoid lateral meniscus,need to identify and repair during surgery after meniscal plasty,which would contribute to the stability of lateral meniscus postoperatively.