Final answer:
The extensor indicis proprius and extensor digiti minimi are positioned ulnar to the extensor digitorum communis tendons for the index and little fingers respectively. They assist in the extension of their respective fingers by attaching to the extensor expansion on the fingers' dorsal side.
Step-by-step explanation:
The extensor indicis proprius (EIP) and extensor digiti minimi (EDM) are two muscles involved in the extension of the fingers. They are situated in the forearm and extend toward the hand, where they attach to the extensor expansion on the dorsal aspect of the fingers. In relation to the extensor digitorum communis (EDC) tendons, which are responsible for extending the fingers, the EIP and EDM can be found on the ulnar side of the forearm. The EIP arises from the posterior surface of the ulna and interosseous membrane and primarily targets the index finger, while the EDM, also arising from similar points, targets the little finger. Both tendons position themselves just ulnar to the EDC tendons of their respective fingers before their insertion.