PC Podiatrist Foot & Ankle Structure 3 — Questions and Answers
Question 1: The calcaneofibular ligament (CFL) resists inversion stress primarily when the ankle is in which position?
- Plantarflexion
- Neutral or dorsiflexion (Correct answer)
- Maximal eversion
- Full supination only
Correct answer: Neutral or dorsiflexion
The CFL is taut when the ankle is in neutral or dorsiflexion, becoming the primary restraint to inversion in those positions unlike the ATFL which is taut in plantarflexion.
Question 2: Which artery is the primary blood supply to the talus and is most at risk in talar neck fractures?
- Posterior tibial artery
- Peroneal artery
- Artery of the tarsal sinus and deltoid branches (Correct answer)
- Anterior tibial artery
Correct answer: Artery of the tarsal sinus and deltoid branches
The talus receives blood primarily via the artery of the tarsal sinus (from the dorsalis pedis/perforating peroneal) and the deltoid branch; talar neck fractures disrupt these, risking avascular necrosis.
Question 3: The medial longitudinal arch is primarily maintained dynamically by which tendon?
- Peroneus brevis
- Tibialis anterior
- Tibialis posterior (Correct answer)
- Flexor hallucis longus
Correct answer: Tibialis posterior
The tibialis posterior tendon is the primary dynamic support of the medial longitudinal arch; its insufficiency leads to adult-acquired flatfoot deformity.
Question 4: The spring (plantar calcaneonavicular) ligament primarily supports which structure?
- Lateral column of the foot
- Head of the talus (Correct answer)
- Base of the fifth metatarsal
- Cuboid bone
Correct answer: Head of the talus
The spring ligament forms a sling under the talar head, supporting it and maintaining the medial longitudinal arch; its attenuation contributes to flatfoot.
Question 5: Which osseous structure forms the lateral wall of the tarsal tunnel?
- Medial malleolus
- Calcaneus (Correct answer)
- Talus
- Flexor retinaculum
Correct answer: Calcaneus
The tarsal tunnel is bordered laterally and inferiorly by the calcaneus, medially by the flexor retinaculum, and superiorly by the medial malleolus.
Question 6: The Chopart (midtarsal) joint is formed by which two articulations?
- Talonavicular and calcaneocuboid joints (Correct answer)
- Subtalar and ankle joints
- Naviculocuneiform and cuboid-metatarsal joints
- First and second tarsometatarsal joints
Correct answer: Talonavicular and calcaneocuboid joints
Chopart's joint (transverse tarsal joint) consists of the talonavicular joint medially and the calcaneocuboid joint laterally, separating the hindfoot from the midfoot.
Question 7: The sesamoid bones of the hallux are embedded within which structure?
- Plantar plate of the first MTP joint
- Tendons of flexor hallucis brevis (Correct answer)
- Abductor hallucis tendon
- Extensor hallucis longus tendon
Correct answer: Tendons of flexor hallucis brevis
The two sesamoid bones (medial tibial and lateral fibular) are incorporated within the two heads of the flexor hallucis brevis tendon beneath the first MTP joint.
PC Podiatrist Foot & Ankle Structure 3
The calcaneofibular ligament (CFL) resists inversion stress primarily when the ankle is in which position?