1.Between February 1997 and October 1998, 11 patients(aged 11-19 years) with acute traumatic hemarthrosis underwent the arthroscopic procedure under extra epidural anesthesia.

1.1997年2月～1998年8月在关镜下诊治的11例青少年创伤性膝关。

2.Although epidural anesthesia is a common practice in neuraxial blockade, difficult access to the epidural space is a frequent problem in operating theaters.

2.硬膜外阻断术是一种常用的区域麻醉，但在实施上却经常遭遇到困难。