Bilateral discoid medial Meniscus: Two case reports.

RATIONALE

Discoid meniscus is an anatomical congenital anomaly more often found in the lateral meniscus. A discoid medial meniscus is a very rare anomaly, and it is difficult to diagnose a bilateral discoid medial meniscus because not all the discoid medial menisci are symptomatic. Herein, we report 2 cases of bilateral discoid medial meniscus.

PATIENTS CONCERNS

Case1: a 23-year-old man presented with complaints of pain and occasional clicking of the right knee for 6 years, the left knee was asymptomatic. Case 2: a 51-year-old woman had a 1-month history of pain and a feeling of "giving away" in both knees.

DIAGNOSES

Based on physical examination and magnetic resonance imaging (MRI) findings, they were diagnosed with bilateral discoid medial meniscal tears.

INTERVENTIONS

Case 1: partial meniscectomy and reshaping were performed for the torn discoid medial meniscus of the right knee only. Case 2: partial medial meniscectomy and reshaping were performed for the torn discoid medial meniscus on both knees.

OUTCOMES

The postoperative pain and the recovery of joint function were observed. The average follow-up time of 2 patients was 1 year. The Lysholm score of 2 patients was improved from 55 to 95 and 40 to 90 respectively. The pain of knee joint was relieved and the symptoms of disharmony were obviously improved.

LESSONS

We recommend preservation of the discoid medial meniscus in asymptomatic patients. Meniscectomy and reshaping for injured discoid medial meniscus produces promising short-term results.