Final answer:
Reposition is the movement of returning the thumb to its anatomical position beside the index finger, after opposition, which is moving the thumb to touch the tips of the other fingers. This action is true and is facilitated by the unique saddle joint between the trapezium carpal bone and the first metacarpal bone.
Step-by-step explanation:
Reposition is a movement of the thumb whereby it is returned to its anatomical position, which is next to the index finger, after opposition—a movement that brings the tip of the thumb in contact with the tips of other fingers.
This process is facilitated by the unique saddle joint located at the first carpometacarpal joint, involving a combination of flexion and abduction of the thumb.
Therefore, when a thumb is brought into contact with another digit and then moved back to its original place next to the index finger, this movement is known as opposition followed by reposition, making the claim true that reposition brings the thumb into contact with another digit.
The first metacarpal bone, which is at the base of the thumb, provides the freedom of motion essential for these movements. This bone's separation from the other metacarpal bones is crucial for the thumb's mobility, playing a vital role in tasks such as gripping and manipulating objects.