sit with one's hands around one's knees

3歳の息子をウサギ用のケージに監禁して死亡させ、川に遺棄したとして両親が逮捕されました。

A Tokyo couple accused of locking their 3-year-old son in a rabbit cage for three months and causing him to die didn't let him wear trousers even in the winter, investigative sources have disclosed.

The arrested pair was quoted as saying that Rikuto wore a pajama top but wore no pajama bottoms, only diapers. A weight had been placed on the opening on the top of the rabbit cage so that he couldn't open it from the inside. Since the rabbit cage wasn't big enough for Rikuto to stand up in, he always sat with his hands around his knees, the pair was quoted as telling police.

http://sp.mainichi.jp/english/english/newsselect/news/20150501p2a00m0na006000c.html

今回気になったのは、"sit with hands around his knees"という表現です。手持ちの辞書には載っていませんでしたが、ネットの画像検索で調べてみると、「体育座り」を意味していることが分かりました。

少年が閉じ込められていたウサギ用のケージには重石が乗っていて、常に体育座りの体制でいるほかなかったそうです。このような事件が起きるとは非常に悲しいです。(ninetails)