A 24-year-old footballer twists his knee and it locks at 30 degrees of flexion. He cannot fully extend it despite several days of quadriceps exercises. McMurray test produces a palpable clunk over the medial joint line. The tear pattern most likely responsible for the locking is:

• A Radial tear of the lateral meniscus
• B Oblique flap tear of the medial meniscus
• C Degenerate horizontal cleavage tear of the medial meniscus
• D Bucket-handle (vertical longitudinal) tear of the medial meniscus ✓

Explanation

Locking of the knee in partial flexion is the classic presentation of a bucket-handle tear, a vertical longitudinal tear whose central displaced fragment flips into the intercondylar notch and mechanically blocks extension. Radial and flap tears cause pain and catching but rarely true mechanical locking, while horizontal cleavage tears are degenerative and produce vague symptoms in older patients. A positive McMurray cluck at the medial joint line further supports a medial meniscal lesion.

Reference: Miller's Review of Orthopaedics, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.