Whereas I open his joint capsule, I could immediately see this ACL was all frayed.

当我打开他的关节囊时，我立刻看到前交叉韧带都磨损了。

These joints are synovial, meaning they have a joint capsule and a small amount of synovial fluid in between.

关节突关节是滑膜关节，即关节有关节囊，囊内有少量滑液。

But when these cells recognise a foreign molecule, they use cytokines to signal other immune cells to migrate to the joint capsule and the joint space that's under attack, cells like neutrophils.

但当这些细胞识别到异物时，它们就会分泌细胞因子募集免疫细胞，如中性粒细胞，来到受攻击的关节囊和关节腔。