Osteology of the Foot - Accessory Bones

Question 1

accessory bone

Answer 1

do not appear as part of the normal osteology of the foot

Question 2

are accessory bones the result of a pathological condition or fracture

Answer 2

no

Question 3

types of accessory bones

Answer 3

ossicles

sesamoids

Question 4

ossicles

Answer 4

are the result of anomalous development or anomalous ossification patterns

Question 5

sesamoids

Answer 5

are found in tendons and joint capsules and usually present to reduce the friction of a tendon or later the pull of a tendon

Question 6

os trigonum (talus secondarius or talus accessorius)

Answer 6

located posterior to the lateral tubercle on the posterior surface of the body of the talus

Question 7

sometimes os trigonum may fuse forming

Answer 7

a Stieda’s process

Question 8

Shepard’s fracture

Answer 8

is a fracture of the lateral tubercle

Question 9

os tibiale externun

Answer 9

located just posterior to the tuberosity of the navicular

sometimes may fuse

Question 10

some clinicians call os tibiale externum a

Answer 10

prehallux

Question 11

os intermetatarseum

Answer 11

• commonly located btwn the 1st and 2nd MT base on the dorsal aspect
• may also be found btwn the 4th and 5th MT base

Question 12

os supranaviculare (os talonavicular dorsale)

Answer 12

located on the dorsal aspect of the talonavicular joint

Question 13

os calcaneum secundum (os calcaneus secondarius)

Answer 13

commonly located on the dorsal aspect of the calcaneocuboid joint but may be found on the plantar aspect

Question 14

os supratalare (talus secondarius)

Answer 14

located at the proximal aspect on the dorsal surface of the neck of the talus

Question 15

os vesalianum

Answer 15

located posterior to the tuberosity of the base of the 5th NT

Question 16

accessory ossicle of hallux

Answer 16

located on the medial or lateral aspect of the base of the distal phalanx (dorsal surface)

Question 17

os subtibiale

Answer 17

located just inferior to the anterior colliculus of the medial malleolus

Question 18

os subfibulare

Answer 18

located just inferior to tip of lateral malleolus

Question 19

os sustentaculi

Answer 19

located near the sustentaculum tali of the calcaneus (plantar surface)

Question 20

os calcaneum secundum (os calcaneus secondarius)

Answer 20

commonly located on the dorsal aspect of calcaneocuboid joint but may be found on the plantar aspect

Question 21

os peroneum

Answer 21

located in the tendon of fibularis longus near the fibular notch (dorsum surface)

Question 22

os interphalangeus (IPJ sesamoid of the hallux)

Answer 22

located in the IPJ joint capsule of the hallux on the plantar aspect