Osteology (Part 2): Talus Flashcards
(35 cards)
1
Q
Talus (Astraglus)
A
- Links leg and foot
- Transmit forces between foot and leg
- 2nd largest foot/ankle bone
- No muscular insertions
- Multiple ligament attachments
2
Q
Trabeculae of talus orientated
A
- Anteriorly toward navicular
- Posteriorly toward calcaneus
3
Q
3 parts of talus
A
- Head
- Body
- Neck
4
Q
Head of talus
A
- Angled anteriorly and medially
5
Q
Body of talus
A
- Square shaped portion
- Articulates with the tibia/fibula
- Convex anterior to posterior
- Concave medial to lateral
6
Q
Neck of talus
A
- Narrowed portion between the head and body
7
Q
Talus forms synovial joints with the
A
- Tibial plafond, medial malleolus and lateral malleolus of fibula (talocrural joint)
- Calcaneus (subtalar joint)
- Navicular (midtarsal joint)
8
Q
Structures of body of talus
A
- Trochlea (trochlea tail)
- Lateral malleolar facet
- Lateral process
- Medial malleolar facet
- Posterior process
- Posterior facet (posterior calcaneal facet)
9
Q
5 surfaces of body of talus
A
- Posterior
- Lateral
- Inferior
- Medial
- Superior
10
Q
Trochlea (trochlea tali)
A
- Large cartilage covered superior articular surface
- Wider anteriorly than posteriorly (wedged-shaped)
- Articular facet for inferior transverse tibofibular ligament (posterior lateral surface of trochlea)
11
Q
Trochlea (trochlea tali) articulates with
A
- Tibial plafond
- Only about 2/3 of trochlea covered by plafond in any position
12
Q
Lateral malleolar facet
A
- Concave triangular articular face (apex inferior)
- Continuous with trochlea
- Extends onto lateral process
- Articulates with lateral malleolus
13
Q
Lateral process of talus body
A
- Lateral malleolar facet extends onto lateral process (articulates with fibula)
- Load-bearing structure
- Contributes to the ankle mortise and lateral part of subtalar joint
- Lateral talocalcaneal ligament attaches
- Fracture in “Snowboarders fracture”
- Dorsiflexion injury
14
Q
Medial malleolar facet
A
- Slightly concave, comma-shaped facet (tear-drop shaped) on medial talus
- Continuous with trochlea
- Extends more anteriorly than lateral malleolar facet, slightly concave
- Articulates with medial malleous
15
Q
Posterior process
A
- Formed by 2 smaller projections
- Medial tubercle
- Lateral tubercle
- Sulcus (groove) for flexor hallucis longus tendon is between tubercles
16
Q
Medial tubercle (posterior process)
A
- Attachment of posterior tibiotalar ligament
17
Q
Lateral tubercle (posterior process)
A
- Attachment of posterior talofibular ligament
- Larger than medial (significant enlargement is called Steida’s process)
- Fracture of lateral tubercle is called “Shepard’s Fracture”
- Os trigonum (accessory ossicle, failure of fusion of lateral tubercle)
18
Q
Posterior facet of talus (posterior calcaneal facet)
A
- Located on the inferior surface of the body
- Large concave facet
- Articulates with the posterior facet of calcaneus (posterior talar facet)
- Subtalar joint (anatomic subtalar joint)
19
Q
Neck (collum tail)
A
- Begins at the anterior border of trochlea
- Not in line with or in the same horizontal plane as body
- Foramina for nutrient vessels (fracture can cause AVN of the talus)
20
Q
Neck (collum tail) angles
A
- In the horizontal plane, shifted medially compared to the body
- In the sagittal plane, angled inferiorly
- Angled 10-20⁰ (larger in children) medially from longitudinal axis (neck and head)
21
Q
Neck (collum tail) is an attachment point for
A
- Cervical ligament
- Part of the inferior extensor retinaculum
22
Q
Sulcus tali
A
- Groove on inferior surface that runs anterolaterally
- Wider laterally
- Multiple ligament attachments
23
Q
Sulcus tali runs between
A
- Anterior/middle facets of talus
- Posterior facets of talus
24
Q
Sulcus tali combines with calcaneal sulcus to form
A
- Tarsal Canal
- Sinus tarsi
25
Head of talus is palpable between
- Sustentaculum tali
| - Navicular tuberosity
26
Structures of head of talus
- Navicular articular surface
- Anterior/middle facet of talus
- Articular facet for spring ligament
- Angle of talar torsion
27
Navicular articular surface
- Located at the anterior end of the head
- Articulates with navicular
- Continuous with anterior facet of talus
28
Anterior/middle facet of talus (anterior/middle calcanean facet)
- Located on inferior surface of the head of talus
| - Articulates with anterior/middle facet of calcaneus (anterior/middle talar facet)
29
Anterior/middle facet of talus (anterior/middle calcanean facet) can either be
- Confluent with each other
- Separated by a small ridge
- Sometimes all 3 anterior, middle, and posterior facets are all confluent
30
Articular facet for spring ligament (plantar calcaneonavicular ligament)
- Medially located on inferior aspect of talar head
| - Articulates with cartilage of spring ligament
31
Angle of talar torsion
- Angle between longitudinal axis of head and transverse plane
- Head is rotated around talar body
- Clockwise on the right, counterclockwise on the left
- ~40-60 degrees
- Lateral side is more superior
32
Talus blood supply
- Branches from dorsalis pedis, posterior tibial, fibular arteries
33
Neck/head of talus blood supply
- Branches from dorsalis pedis (medial/lateral tarsal) and anterior tibial)
- Artery of tarsal canal and Artery of sinus tarsi
34
Body of talus blood supply
- Deltoid artery
- Artery of sinus tarsi and artery of tarsal canal directly
- Other branches from posterior tibial
35
Deltoid artery arises from
- Artery of tarsal canal
| - OR directly off posterior tibial
