NBCOT Upper Extremity Practice Test

Radial nerve palsy causes wrist drop, so the goal is to support the wrist in a position that still allows finger movement and functional grip. A cock-up splint achieves this by holding the wrist in slight extension while keeping the fingers free to move. This extended-wrist position optimizes the length-tension relationships of the hand muscles, enabling use of the intact finger flexors and thumb for grasp and pinch despite weakness in finger extension. It provides stability at the wrist without immobilizing the fingers, which is ideal for restoring functional activity after radial nerve injury. Other splints either immobilize the thumb (thumb spica), immobilize the ulnar digits (ulnar gutter), or keep the hand in a more neutral resting position (resting hand splint) and don’t specifically address extending the wrist to facilitate finger movement, making them less suitable for radial nerve palsy.