Final answer:
Dorsal DRUJ (distal radioulnar joint) instability is most stable in the supinated position. This is because in supination, the radius and ulna lie parallel, providing a stable configuration for the joint.
Step-by-step explanation:
The question pertains to the position in which dorsal distal radioulnar joint (DRUJ) instability is most stable. The DRUJ is a joint located between the radius and ulna bones at the wrist. It allows for pronation and supination movements of the forearm. When considering instability, or the tendency for the bones to move out of their normal position, the joint is generally most stable in supination.
In supination, the radius and ulna are positioned parallel to each other, which is the most stable configuration for the joint. Conversely, in pronation, the radius crosses over the ulna leading to a less stable position, which could exacerbate the instability. Therefore, patients with dorsal DRUJ instability might be advised to keep their forearm in a supinated position to maintain stability and reduce discomfort.