The Foot.

The tip of the external malleolus is 1/4 inch lower and 3/4 inch posterior to that of the internal malleolus. The line of the ankle-joint can be felt on either side of the extensor tendons, and when the foot is extended a prominence is formed by the anterior part of the superior articular surface of the astragalus below the anterior border of the lower end of the tibia.

A finger's breadth below the tip of the internal malleolus is the sustentaculum tali; 1 1/4 inches in front of the latter is the tubercle of the scaphoid; close above it is the tendon of tibialis posticus.

A finger's breadth below the tip of the external malleolus is the peroneal tubercle of the os calcis, a guide to the two peronei tendons.

The line of the tarso-metatarsal joints extends nearly 1 inch further forwards on the inner than on the outer surface of the foot.

The metatarsophalangeal joints are situated one inch behind the web of the toes.

Crossing the front of the ankle-joint, from within outwards, are the tendons of tibialis anticus, extensor longus hallucis, extensor longus digitorum, and peroneus tertius. The extensor brevis digi-torum forms a fleshy pad over the calcaneo-cuboid joint. The abductor hallucis forms a fleshy pad along the inner border of the foot.

The dorsalis pedis artery is mapped out by a line drawn from a point midway between the two malleoli (the termination of the anterior tibial artery) to the hinder end of the first interosseous space. The internal saphenous vein and nerve lie between the internal malleolus and the tendon of tibialis anticus; the external saphenous vein and nerve follow the tendon of peroneus brevis.

The internal plantar vessels and nerves lie along a line drawn from the under surface of the inner tuberosity of the os calcis to the interval between the first and second toes. The external plantar vessels and nerves are on a line drawn from the middle of the under surface of the heel to the fourth toe; the course of the plantar arch is mapped out by a line drawn across the sole from the inner side of the base of the fifth metatarsal to the hinder end of the first interosseous space.