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Published on: October 20, 2023
Extra-articular patellar dislocation with vertical axis rotation
Chen Yang1, Yubao Gong, Xiaoyu Wen
1Department of Orthopedic Surgery, The First Hospital of Jilin University, Xinmin Str 71, Changchun 130021, Jilin, China.
Abstract:
Extra-articular vertical dislocation is very rare. It occurs when the patella is forced crossing the lateral femoral trochlear surface, and rotated simultaneously along its longitudinal axis at about 90°, resulting in a wedged dislocation against lateral condyle. Reduction has been reported to require general anesthesia and an open procedure. We report a 19-year-old boy with extra-articular patellar dislocation, and a successful reduction was done by manipulation under local anesthesia. We believe that the mechanism of lateral vertical dislocation is the fulcrum mechanism.
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