He underwent surgery due to an injury to the opponens digiti minimi muscle.

He injured his little finger.

He injured his little finger.

There is a serious opposition between them.

He and she were standing against each other due to a disagreement.

He is doing a special exercise to strengthen his extensor digiti minimi.

I strained a muscle at the gym yesterday.

My opponens pollicis muscle hurts.

He is doing special exercises to strengthen the opponens digiti minimi muscle of his foot.

He is doing a special exercise to strengthen his flexor digiti minimi brevis.