Research Article

A Retrospective Study of Unicompartmental Knee Arthroplasty Functional Outcome and the Incidence of Medial Meniscus Posterior Root Tear in Spontaneous Osteonecrosis of the Knee

Figure 3

(a) Cleft sign: interruption of the medial meniscus at the posterior horn in axial plane. (b) Ghost sign: empty image of medial meniscus.
(a)
(b)