The abductor pollicis longus muscle is a muscle located in the forearm. It is one of several muscles that make up the deep group of the extrinsic muscles of the hand, which are responsible for moving the thumb and fingers. The abductor pollicis longus muscle is responsible for extending the thumb, which means it helps to move the thumb away from the palm and towards the top of the hand. This movement is important for grasping and holding objects.

The abductor pollicis longus muscle is located in the forearm, along the outer aspect of the radius bone. It originates from the posterior aspect of the ulna and interosseous membrane, and inserts onto the base of the distal phalanx of the thumb.

One example of how the abductor pollicis longus muscle is used is when you pick up a pencil or other small object between your thumb and fingers. To do this, you need to extend your thumb away from your palm and towards your fingers, which is facilitated by the abductor pollicis longus muscle. This movement allows you to grip objects securely and control their movement.

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