Lecture 14 - Foot

Question 1

How many bones are in the foot?

Answer 1

• 26 total bones:
• 7 tarsal bones
• 5 metatarsal bones
• 14 phalanges

Question 2

What are the 7 tarsal bones?

Answer 2

• calcaneus
• talus
• navicular
• cuboid
• cuneiform (3)

Question 3

What is the calcaneus bone?

Answer 3

• The heel bone
• Posterior, inferior tarsal bone that forms the heel of the foot
• The medial calcaneus has a prominent bony extension called the sustentaculum tali, which supports the medial side of the talus bone

Question 4

What is the talus bone?

Answer 4

• Articulates superiorly with the tibia & fibula at the ankle joint
• Also articulates inferiorly with the calcaneus bone & anteriorly with the navicular

Question 5

What is the navicular bone?

Answer 5

• Articulates posteriorly with the talus bone, laterally with the cuboid bone, & anteriorly with the medial, intermediate, & lateral cuneiforms

Question 6

What is the cuboid bone?

Answer 6

• Articulates posteriorly with the calcaneus, medially with the lateral cuneiform, & anteriorly with the 4th-5th metatarsals

Question 7

What are the 3 cuneiform bones?

Answer 7

• 1st (medial) cuneiform
• 2nd (intermediate) cuneiform
• 3rd (external) cuneiform

Question 8

What is the 1st (medial) cuneiform bone?

Answer 8

• the largest of the 3 bones
• it is situated at the medial side of the foot, anterior to the navicular bone & posterior to the base of the 1st metatarsal

Question 9

What is the 2nd (intermediate) cuneiform bone?

Answer 9

• situated between the other 2 cuneiform bones (the medial and lateral cuneiforms)
• articulates with the navicular posteriorly, the second metatarsal anteriorly & with the other cuneiforms on either side

Question 10

What is the 3rd (lateral) cuneiform?

Answer 10

• is intermediate in size between the other two cuneiform bones, It occupies the center of the front row of the tarsal bones
• Articulates between the intermediate cuneiform medially, the cuboid laterally, the navicular posteriorly, & the 1st metatarsal in front

Question 11

What are the metatarsals?

Answer 11

• refer to the five long bones found in each foot. They are numbered I to V, from medial to lateral
• the metatarsal and tarsal bones help to form the main arches of the foot, which are essential for weight-bearing & walking

Question 12

What are the phalanges of the foot?

Answer 12

• Similar to the fingers, the big toe has proximal & distal phalanges
• The remaining toes have proximal, middle, & distal phalanges

Question 13

What are the tarsometatarsal joints?

Answer 13

• Between the bases of the metatarsals and the distal row of tarsal bones
• Metatarsal 1- Cuneiform 1
• Metatarsal 2- Cuneiform 2
• Metatarsal 3- Cuneiform 3
• Metatarsal 4 & 5 - Cuboid

Question 14

What are the metatarsalphalangeal joints?

Answer 14

• Between the heads of the metatarsals and the proximal phalanges
• Joint capsules are reinforced medially and laterally (collateral ligaments) & more flexible on the dorsal & ventral aspects (no palmar plates)

Question 15

What are the interphalangeal joints?

Answer 15

• the articulations between consecutive phalanges of the foot
• Each foot has 9 interphalangeal joints: 2 on each of the 4 lateral toes & one on the big toe

Question 16

What are the 2 types of interphalangeal joints?

Answer 16

• Proximal Interphalangeal Joints: between the heads of the proximal phalanges and the base of the middle phalanges
• Distal Interphalangeal Joints: between the heads of the middle phalanges and bases of the distal phalanges

Question 17

What are the 3 arches of the foot?

Answer 17

• medial longitudinal arch
• lateral longitudinal arch
• transverse/mid-tarsal arch

Question 18

What is the medial longitudinal arch?

Answer 18

• Larger, taller arch
• Formed by calcaneal tuberosity, talus, navicular, cuneiforms (3) & 1st 3 metatarsals
• Supported by the Spring ligament & Plantar Fascia

Question 19

What is the lateral longitudinal arch?

Answer 19

• Relatively flat, lower than the medial arch
• Supported by the long plantar ligament, short plantar ligament, bifurcate ligament, & planter fascia

Question 20

What is the transverse/mid-tarsal arch?

Answer 20

• Forms a medial-lateral curvature of the mid-foot
• Created by the bases of metatarsals 1-5

Question 21

What are the 2 types of arch heights?

Answer 21

• pes planus
• pes cavus

Question 22

What is pes planus?

Answer 22

• the loss of the medial longitudinal arch of the foot, heel valgus deformity, and medial talar prominence
• Known as “flat foot’

Question 23

What is pes cavus?

Answer 23

• A foot with an abnormally high plantar longitudinal arch

Question 24

What is the talocrural joint?

Answer 24

• formed between the distal tibia-fibula and the talus, & is commonly known as the ankle joint
• It is a hinge joint & allows for dorsiflexion and plantarflexion movements in the sagittal plane

Question 25

What is the stability of the talocrural joint?

Answer 25

• with its oblique rotation axis & the specific shape of the talus, when the talus is moved in its largest anterior position, the joint was more unstable in plantarflexion

Question 26

What is the subtalor joint?

Answer 26

• articulation between two of the tarsal bones in the foot: the talus & calcaneus
• The joint is classed structurally as a synovial joint & functionally as a plane synovial joint
• allows for rotation of the foot, clinically known as inversion and eversion of the foot

Question 27

What are the 3 lateral ligaments of the subtalor joint?

Answer 27

• anterior/posterior Talofibular ligament
• calcaneofibular ligament

Question 28

What is the anterior Talofibular ligament?

Answer 28

• resist inversion and plantar flexion of the ankle joint
• originates from the anterior edge of the lateral malleolus of the fibula & attaches to the neck of the talus, in front of the lateral malleolar facet

Question 29

What is the posterior Talofibular ligament?

Answer 29

• fairly strong band that runs horizontally medially
• This ligament is under greater strain in full dorsiflexion of the ankle
• Resists posterior displacement of the talus

Question 30

What is the calcaneofibular ligament?

Answer 30

• Attaches to the tip of the lateral Malleolus proximally & to the lateral surface of the calcaneus distally
• Aids Talofibular stability during Dorsiflexion
• Restrain inversion of the calcaneus with respect to the fibula

Question 31

What is the spring ligament?

Answer 31

• thick wide band of cartilaginous connective tissue that supports the medial longitudinal arch of the foot
• functions as static restraint of the medial longitudinal arch

Question 32

What is the long plantar ligament?

Answer 32

• the longest and strongest ligament of the foot, Running along the base of the foot from the heel bone (calcaneus) to the base of the metatarsal bones
• it assists in forming the longitudinal arch of the foot & keeping the calcaneocuboid joint & the midtarsal joint stable

Question 33

What is the short plantar ligament?

Answer 33

• connects the inferior calcaneus to the plantar aspect of the cuboid bone & runs slightly medial and deep to the long plantar ligament
• Stabilizer of the calcaneocuboid joint

Question 34

What is the plantar fascia?

Answer 34

• a thick band of tissue that runs across the bottom of each foot and connects the heel bone to the toes