PMC8553514_01
MRI showed a thickening of the medial plica protruding far into the medial patellofemoral joint (PFJ).
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As MRI showed a thickening of the medial plica protruding far into the medial patellofemoral joint (PFJ) (Figure 1), we performed arthroscopic resection; however, there was little improvement.
Valgus knee and patellar instability appeared on a plane X-ray with a large Q angle: 17 , tilt angle: 21 , and lateral shift: 18%.
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Afterwards, valgus knee and patellar instability appeared on a plane X-ray with a large Q angle: 17 , tilt angle: 21 , and lateral shift: 18% (Figure 2).
MRI showed diffuse thickening of both ACLs, which are called celery stalk sign, with high inhomogeneous intensity in the T2-weighted and proton density weighted images.
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MRI showed diffuse thickening of both ACLs with high inhomogeneous intensity in the T2-weighted and proton density weighted images (Figure 3).
Arthroscopy showed (a, d) hypertrophied ACLs and the (b, d) presence of intraligamentous mucoid degeneration. (e) The posterolateral bundles in the ACLs were slightly loose at the lateral portion of the intercondylar notch. (c, e) Further, there was a partial depression of cartilage in the same region.
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Further, there was a partial depression of cartilage in the same region (Figure 4).
(a, c) Both hematoxylin and eosin stain, (b) Alcian blue stain, and (d) Masson trichrome stain. All of these results indicated the presence of mucoid degeneration.
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To support our interventions, pathological results also indicated the presence of mucoid degeneration in the ACLs (Figure 5).