What type of injury is prevented by proper positioning of the arm on the OR bed armboards?

Proper positioning of the arm on the operating room (OR) bed armboards primarily helps to prevent ulnar nerve injury. The ulnar nerve runs along the inner side of the elbow and is particularly susceptible to injury if the arm is positioned incorrectly, such as being overly extended or leaning against a hard surface. When the arm is properly positioned, particularly in a way that keeps the elbow in a relaxed and neutral position, the risk of compression or stretching of the ulnar nerve is significantly reduced.

In surgical settings, ensuring that the arm is not hanging off the bed or is positioned in a manner that puts pressure on the elbow area is crucial to preserving nerve function. This preventative measure is essential for maintaining the integrity and functionality of the ulnar nerve, which innervates parts of the hand and is responsible for fine motor skills.