knuckle spindle

例句：

1. 1. The knuckle spindle is a crucial part of the human hand.
   指骨柄是人类手的重要组成部分。
2. 2. The knuckle spindle helps to stabilize the hand during movement.
   指骨柄有助于在运动中稳定手部。
3. 3. The knuckle spindle is often used in surgical procedures to repair damaged tissue.
   指骨柄常用于外科手术中修复受损组织。