He was shot in the back of the knee.

他被子弹击中了腘窝。

《牛津词典》

Above the back of the knee, the sciatic nerve divides into two nerves, the tibial and the common peroneal nerve, both of which serve the lower leg and foot.

在膝关节后上方，坐骨神经分成两条神经，胫神经和腓总神经，它们都支配小腿和足。

youdao

For example, knee injuries sometimes occur because running strengthens the back of your legs more than the front of your legs.

比如说膝盖损伤是因为跑步加强的后退的锻炼而忽略了前腿。

youdao

He had fluid drained from the back of the knee after struggling through the two games he played during that stretch, and said after the Knicks' morning shootaround he feels much better.

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It's not as bad as I first thought anyway, but I'm feeling a bit of pain in my knee and the back of my calf and down my shin so we'll see how it is.

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The Wasps forward was sin-binned for putting his knee into the back of Springboks scrum-half Fourie du Preez.

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