He is doing special exercises to strengthen his extensor digitorum longus.

He is doing special exercises to strengthen his extensor digitorum brevis muscle.

He underwent surgery due to an injury to his extensor pollicis brevis.

He injured his extensor pollicis longus.

He is doing special exercises to strengthen his extensor hallucis longus.

He had difficulty walking due to an injury to his extensor hallucis brevis.

He is doing special exercises to strengthen his extensor carpi ulnaris.

He is doing a special exercise to strengthen his extensor carpi radialis brevis.

The extensor carpi radialis longus is a part of the arm muscles and helps in the movement of the wrist.

Shun winked his eyes.