Tarsal Bones - Cuboid and Navicular

The cuboid bone, like its name suggests, has a cube shape when viewed from above, but has ridges and grooves on its plantar surface. It is the lateral bone in the distal series of tarsal bones and articulates with the fourth and fi fth metatarsals. With a good imagination one can visualize the hull of a ship when observing the navicular bone. This ship-shaped bone is an intermediate bone between the talus and the three cuneiforms on the medial aspect of the foot.

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The wedge-shaped cuneiforms are the distal tarsal bones on the medial aspect

of the ankle. They articulate with the three medial metatarsal bones. Their wedge shapes contribute to the formation of the transverse arch of the foot.

Phalanges Similar in number to the phalanges of the hand, the phalanges of the foot are much smaller than those of the hand, with the exception of the large

fi rst toe. The proximal phalanges have broad bases that form the widest part of the bone. From the base a narrow shaft projects to a rounded head with a trochlear articular surface. The middle and distal phalanges are short bones that can be easily distinguished by their distal ends. The middle phalanges have a trochlear articular surface on their distal head, while the distal phalanges have a broad tuberosity at their distal ends.

1 Base

2 Shaft or body

3 Head

4 Trochlea

5 Tuberosity of distal phalanx

2

1

4

2

1

3

2

1

Left phalanges

Dorsal view, lateral to left

5

5

1

2

1

4

3

2

1

Left phalanges

Plantar view, lateral to right

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