The os trigonum is an accessory bone of the foot, locates at the posterolateral tubercle of the talus, and occures in about 7% of population.是什么意思_The os trigonum is an accessory bone of the foot, locates at the posterolateral tubercle of the talus, and occures in about 7% of population.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句