2015 ISAKOS Biennial Congress ePoster #1630

What Happens in the Lateral Meniscus of the Contralateral Knee After Discoid Lateral Meniscus Tears?

Sung-Hwan Kim, MD, Seoul KOREA, REPUBLIC OF
Min Jung, MD, PhD, Seoul KOREA, REPUBLIC OF
Inje Cho, MD, Seoul KOREA, REPUBLIC OF
Seong Min Kim, MD, Seoul KOREA, REPUBLIC OF
Seung Joo Ha, MD, Seoul KOREA, REPUBLIC OF
Ji-Young Yoon, MD, Seoul KOREA, REPUBLIC OF
Sang-Woo Jeon, MD, Seoul KOREA, REPUBLIC OF
Yong-Min Chun, MD, PhD, Assoc. Prof., Seoul KOREA, REPUBLIC OF
Chong-Hyuk Choi, MD, PhD, Seoul KOREA, REPUBLIC OF
Sung-Jae Kim, MD, PhD, Seoul KOREA, REPUBLIC OF

Yonsei University College of Medicine, Seoul, KOREA

FDA Status Not Applicable

Summary: Symptomatic discoid meniscus tear on the contralateral side of the patients who underwent unilateral arthroscopic surgery for discoid lateral meniscus tear occurred in 21% of 10 years. The age of the patients at the time of surgery, a significant factor in determining the rate.

Rate:

Abstract:

Introduction

Discoid meniscus is a morphologic variation of the normal meniscus, which is rare in the Western culture but fairly frequent up to 16 % prevalence in eastern Asia. It has recently been reported that the discoid meniscus frequently appears bilaterally, ranging from 79 to 97%. If asymptomatic, discoid lateral meniscus does not need treatment, but if a tear is present and is the cause of pain, limitation of motion or clicking of the knee on movement, surgical management is required. And in such cases, patients are often in question as to whether the opposite knee would eventually show the same symptoms. However, prevalence studies and research focusing on discoid meniscus of the opposite knee is rare, and studies based on such fields promise valuable evidence to be applied in clinical settings. Thus, we have collected the incidence of discoid meniscus of the opposite knee in patients who have undergone surgical management of the discoid meniscus of the symptomatic knee.

Methods

328 patients who underwent arthroscopic management for discoid meniscus tear from January 2000 to February 2013 were collected. Patients were excluded if they had a previous history of knee surgery, or were lost on follow-up. Retrospective analysis of operation records, outpatient medical records and telephone surveys were done on 296 viable cases, and statistical analyses were done using the Statistical Package for the Social Science version 20.0 (SPSS Inc., Chicago, IL). Presence of opposite discoid meniscus was analyzed using the Kaplan-Meier method, and Log-rank method was used to compare age at surgery, type of discoid meniscus, and operative method. Multifactor analysis was done using Cox proportional hazard regression, and results were viewed significant if the p value was less than 0.05.

Results

51 out of 296 patients (17%) underwent arthroscopic surgery of the contralateral knee, and of those 49 cases showed discoid meniscus (96%). Average total follow-up time was 69 months (7 to 164 months), and average age at surgery was 35.6 years. 2-year survival rate was 91%, 5-year was 84%, and 10-year was 79%. Analysis with standard age at surgery set at 40 years showed that prevalence of surgical management of the opposite knee was statistically significant (p = 0.001). However, sex, type of discoid meniscus, side on which discoid meniscus was found, and the method of surgery did not show statistically significant correlation with incidence of surgery at the opposite knee (p > 0.05)

Conclusion

Symptomatic discoid meniscus tear on the contralateral side of the patients who underwent unilateral arthroscopic surgery for discoid lateral meniscus tear occurred in 21% of 10 years. The age of the patients at the time of surgery, a significant factor in determining the rate.