A ring-shaped lateral meniscus is an uncommon morphological variant and its etiology remains unclear. A 38-year-old male was admitted to our institution complaining of right knee pain and locking. Magnetic resonance imaging suggested a bucket-handle tear in the medial meniscus and a discoid lateral meniscus. On arthroscopic evaluation, however, a ring-shaped lateral meniscus was detected in the lateral compartment. The lesion was saucerized as if it were a discoid meniscus. We believe that a ring-shaped meniscus is a rare fourth variant of a discoid meniscus.
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