M3B-Toes and Foot

Toe Phalanges

Great Toe (Hallux) has two phalanges, rest of the digits have 3 per, proximal phalanx of the 1st digit is deviated laterally at MTP Joint

Metatarsals

#1-5 articulate with the distal row of the tarsal bones. Bases #2-5 articulate with each other as well

Metatarsal #1

Shorter and thicker than the rest. It articulates with the medial cuneiform bone, This metatarsal has two sesamoid bones located near the head, on the plantar surface

Metatarsal #2

This metatarsal is the longest of the 5. It articulates directly with all the cuneiform bones

Metatarsal #3

This metatarsal articulates with the lateral cuneiform bone

Metatarsal #4

This bone articulates with the cuboid and the lateral cuneiform

Metatarsal #5

The base is expanded to include a tuberosity (also called a styloid process) on the lateral surface. This tuberosity serves as an attachment point for tendons associated with the lower leg. It articulates with the cuboid

Tarsal Bones

7 bones in each foot, proximal row-talus, calcaneus, navicular distal row- medial, middle, lateral cuneiforms, cuboid

Talus

Most superior of the tarsals and sits on the calcaneus. It consists of a head, neck and body, articulates with the navicular (distally), while the body articulates with the calcaneus (inferiorly), the distal tibia (superiorly/proximally) and the malleoli of the tibia and fibula articulate on the sides of the talus (medially and laterally)

Head of Talus

Directed forward and medially. It has a rounded distal portion that articulates with the navicular

Neck of Talus

Separates the head from the body.  It is marked by a deep groove on the inferior surface that runs obliquely medial to lateral called the sulcus tali

Sulcus Tali

Deep groove on the inferior surface of the neck where it separates the anterior and middle facets from the posterior facet. It forms the bony roof of the sinus tarsi

Body of Talus

The dorsal surface is convex and articulates with the distal tibia

Talar Domes

These articulate with the medial and lateral malleoli of the distal tibia and fibula

Anterior Facet of Talus

Articulates with the head of the calcaneus. This facet is concave in shape and usually located most anteriorly.  It is located anterior and lateral to the middle facet

Middle Facet of Talus

Articulates with the sustentaculum tali of the calcaneus

Posterior Facet of Talus

Articulates with the corresponding facet on the upper surface of the calcaneus, and is deeply concave in the direction of its long axis which runs forward and lateral at an angle of about 45 with the median plane of the body

Calcaneus

Largest of the tarsal bones and is oblong in shape. It receives the entire weight of the body

Posterior Surface of Calcaneus

At the inferoposterior aspect, the tuberosity is thickened for the insertion of the Achilles tendon

Lateral Surface of Calcaneus

Flat but contains the peroneal tubercle that projects between the peroneal tendons

Medial Surface of Calcaneus

Shelf of bone which protrudes significantly in a medial direction. The middle facet on the head of the talus rests on this shelf of bone called the sustentaculum tali

Superior Surface of Calcaneus

Has three articular facets that match with the facets of the inferior talus

Sulcus Calcanei

This structure separates the anterior and middle facets from the posterior facet on the superior surface of the calcaneusSinu

Sinus Tarsi

This is a tunnel for the interosseus talocalcaneal ligaments. Runs in a lateral to medial direction with a posterior angle

Navicular

It is located on the medial side of the foot between the proximal and distal row of the tarsals considered an intermediate tarsal bone

Cuneiform Bones

Located in the distal row of the tarsal bones. The medial is the largest while the middle cuneiform is the smallest

Cuboid

Cube-shaped, the cuboid articulates with the bases of metatarsals #4 and 5 and it also articulates medially with the lateral cuneiform as well as the navicular and proximally with the calcaneus

Longitudinal Arch

Runs lengthwise along the sole of the foot. It is formed by the spring and plantar ligaments

Transverse Arch

Formed by the tarsals and bases of the metatarsals and runs crosswise