2015 ISAKOS Biennial Congress ePoster #1629

Long-Term Results of Arthroscopic Plastic Resection of Lateral Discoid Meniscus

Kota Uematsu, MD, Nara JAPAN
Munehiro Ogawa, MD, PhD, Kashihara, Nara JAPAN
Yusuke Inagaki, MD, PhD, Kashiba, Nara JAPAN
Kazunori Tanaka, MD, Kashihara, Nara JAPAN
Ryota Hara, MD, Nara JAPAN
Yasuhito Tanaka, Prof., Kashihara, Nara JAPAN
Yoshiyuki Fujisawa, MD, Nara, Nara JAPAN
Nara Medical University, Kashihara, Nara, JAPAN

FDA Status Not Applicable

Summary: Plastic resection of discoid meniscus that form close to normal shape was the useful procedure to reduce the rate of osteoarthritic change than subtotal menisectomy.

Abstract:

Introduction

It is generally said that lateral discoid meniscus lead to lateral osteoarthritis of the knee with or without the procedure. The purpose of the resection was to improve the symptom and reduce the incidence of osteoarthritis change. We have performed the plastic resection of discoid meniscus that was the procedure close to normal shape of lateral meniscus. However, it was not obvious whether the formed meniscus keeps the hoop function and avoid the re-rupture or not. The aim of this study was to investigate whether the surgical plastic meniscectomy of the lateral discoid meniscus cause knee arthritis for long term.

Methods

There were 27 knees 34 (male:9, female:18) patients, and the mean age was 12 years (range, 7 to 14), that were performed the plastic meniscectomy arthroscopically (group P). The methods was that the width of middle and posterior segments of resected discoid meniscus was a little narrower than middle segment of medial meniscus. The width of anterior segment of resected discoid meniscus was two-thirds of middle and posterior segments of resected discoid meniscus. The average follow-up periods were about 13 years. The comparative group included 20 knees 20 patients (male:6, female:14), that were performed by the arthroscopic subtotal menisectomy (group S). Clinical findings were evaluated by Tegner activity score, and the radiographic assessment of osteoarthritis was used with the appearance of the sclerotic change of the lateral condyle of femur and tibia and the narrowness of lateral femur-tibia joint. The degeneration and re-rupture were assessed using with Magnetic resonance image (MRI). The qualitative assessment of the formed meniscus was utilized by MRI T1rho value.

Results

In Tegner activity score, there was no significant difference between both groups. In the appearance of sclerotic change of the femur, there was no significant difference, but the change on tibia in group P was founded less than group S (p<0.05). The narrowness of lateral femur-tibia joint was founded in two cases in group S. In some number of patients in both group, MRI T1rho value of remnant formed meniscus were low at follow-up.

Discussion

Plastic resection was the useful procedure to reduce the rate of osteoarthritic change than subtotal menisectomy. The near-normal width of meniscus would make the important function for load distribution. However, the substance of remnant discoid meniscus needs to have no degeneration. Therefore, the indication of this procedure was limited, namely that is children less than twelve years old and preoperative discoid meniscus have no rupture and degeneration. Regeneration therapy needs to introduce to improve the quality of the remnant discoid meniscus.