Final answer:
Viewing the radial tuberosity in profile during a lateral elbow x-ray suggests the forearm is mid-pronated with the palm facing neither fully upwards nor completely to the side.
Step-by-step explanation:
When a lateral elbow x-ray is taken, and the radial tuberosity is visible in profile, it typically indicates that the patient's forearm is in a mid-pronated position. In this position, the palm of the hand is neither completely flat nor fully pronated (in a karate chop position). Given that the radial tuberosity is located on the medial side of the proximal radius, seeing it in profile would correspond to a semi-pronated forearm position where the palm faces obliquely downwards.