Part of P3 affected by sole ulcers?

• A. Dorsal process
• B. Extensor groove
• C. Flexor tuberosity
• D. Proximal articular surface

Answer: (C)

Sole ulcers are subsolar lesions of the coffin bone that arise from pressure where weight is transmitted through the distal phalanx. The flexor tuberosity is the prominent palmar/plantar area on P3 where the deep digital flexor tendon attaches, making it a focal point of weight-bearing and stress. This is why ulcers commonly develop over that site. The other structures listed are on the dorsal aspect or at the top edge of P3 and are not the primary locations for subsolar ulcers: they relate to tendons and joints away from the sole surface, so they aren’t the usual site of ulceration.