Extensor Digitorum Brevis inserts near the base of which toe structure?

• A. Tip of the distal phalanx
• B. Base of the proximal phalanx
• C. Base of the middle phalanx
• D. Tends to insert into the dorsal base of the distal phalanx

Answer: (B)

Extensor digitorum brevis is a short dorsum foot muscle whose slips reach the toes from the calcaneus. It inserts on the bases of the proximal phalanges of toes two through four, allowing these digits to extend at the metatarsophalangeal joints while the extensor digitorum longus handles the more distal phalanges via the extensor expansions. Because its attachments are at the base of the proximal phalanx, not at the middle or distal phalanges, the base of the proximal phalanx is the correct insertion site.