(Fig 1-B.39) Type 4A Ramp lesion

https://youtu.be/c7v4dpgbjmE

https://youtu.be/nKQsItyKAtM

Type 4 Ramp lesion is a complete posterior peripheral tear or complete meniscocapsular junction tear

Subtype 4A:

• This subtype features a complete longitudinal vertical tear of the red-red zone of the meniscus.
  The tear includes the meniscocapsular and meniscotibial attachments, which remain intact.
  However, they are connected to a portion of the posterior horn junction via a free-floating fragment of the meniscus, leading to instability of both structures.
• MRI shows a full-thickness vertical peripheral tear in the red-red zone of the medial meniscal posterior horn. This is identified by a linear high T2 fluid intensity signal extending from the superior to the inferior articular surface.
• Due to the location of this tear pattern, there is a significantly higher healing potential after repair compared to other ramp lesions, which may justify more aggressive repair strategies.

Subtype 4B:

• This pattern involves a complete tear at the junction where the meniscocapsular and meniscotibial fibers attach to the posterior horn of the meniscus.
• MRI reveals a linear high T2 fluid signal intensity extending from the superior to the inferior articular surface, along with disruption of the capsular ligaments.
• The junction consists only of meniscocapsular and meniscotibial fibers. As a result, it does not share the same healing capacity as lesions within the red-red zone of the meniscus, often requiring more extensive repair measures.

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