Tibiofibular Syndesmosis Flashcards

Study the distal tibiofibular syndesmosis, its supporting ligaments, articular relationships, ankle stability, and injury patterns.

Card 1 of 28Question

What type of joint is the distal tibiofibular syndesmosis?

A fibrous joint classified as a syndesmosis.

In This Section

1. What type of joint is the distal tibiofibular syndesmosis?

A fibrous joint classified as a syndesmosis.

2. Which two bones form the distal tibiofibular syndesmosis?

The distal tibia and distal fibula.

3. Which tibial surface articulates with the distal fibula at the syndesmosis?

The fibular notch of the distal tibia.

4. Which part of the fibula participates in the distal tibiofibular syndesmosis?

The rough medial surface of the distal fibula above the lateral malleolar articular facet.

5. What is the principal mechanical function of the tibiofibular syndesmosis?

To maintain the relationship between the distal tibia and fibula and stabilize the ankle mortise.

6. What is the ankle mortise?

The socket formed by the distal tibia and fibula that accommodates the trochlea of the talus.

7. Which four principal ligamentous structures stabilize the distal tibiofibular syndesmosis?

The anterior inferior tibiofibular ligament, posterior inferior tibiofibular ligament, inferior transverse ligament, and interosseous ligament.

8. Where does the anterior inferior tibiofibular ligament attach?

From the anterior distal tibia to the anterior distal fibula.

9. What is the primary function of the anterior inferior tibiofibular ligament?

It resists separation and excessive external rotation of the distal fibula relative to the tibia.

10. Where does the posterior inferior tibiofibular ligament attach?

From the posterior distal tibia to the posterior distal fibula.

11. What is the role of the posterior inferior tibiofibular ligament?

It reinforces the posterior syndesmosis and resists excessive separation of the distal tibia and fibula.

12. Where is the inferior transverse tibiofibular ligament located?

Along the posterior aspect of the distal tibiofibular articulation, inferior to the posterior inferior tibiofibular ligament.

13. How does the inferior transverse tibiofibular ligament contribute to ankle stability?

It reinforces the posterior margin of the ankle mortise and helps support the talus.

14. What is the distal tibiofibular interosseous ligament?

A dense fibrous thickening of the distal interosseous membrane connecting the tibia and fibula.

15. What is the relationship between the interosseous membrane and the distal tibiofibular syndesmosis?

The interosseous membrane extends between the tibia and fibula, with its distal thickening contributing to syndesmotic stability.

16. How does the distal tibiofibular syndesmosis differ from the proximal tibiofibular joint?

The distal articulation is fibrous, whereas the proximal tibiofibular joint is synovial.

17. What movement normally occurs at the distal tibiofibular syndesmosis during ankle motion?

Small amounts of fibular translation, rotation, and separation accommodate talar movement.

18. Why does ankle dorsiflexion produce slight widening of the ankle mortise?

The wider anterior portion of the talar trochlea enters the mortise.

19. Which arteries contribute to the blood supply of the distal tibiofibular syndesmosis?

Branches of the anterior tibial, posterior tibial, and fibular arteries.

20. Which nerves contribute sensory branches to the distal tibiofibular syndesmotic region?

Primarily branches of the deep fibular and tibial nerves.

21. What is the common clinical name for an injury to the distal tibiofibular syndesmosis?

A high ankle sprain.

22. What is a typical mechanism of a syndesmotic ankle sprain?

Forced external rotation of the foot relative to the leg, often with dorsiflexion.

23. Which syndesmotic ligament is commonly injured first during an external rotation ankle sprain?

The anterior inferior tibiofibular ligament.

24. What does diastasis of the distal tibiofibular syndesmosis mean?

Abnormal separation of the distal tibia and fibula.

25. What is a Maisonneuve fracture in relation to syndesmotic injury?

A proximal fibular fracture associated with injury to the distal tibiofibular syndesmosis and medial ankle structures.

26. Which radiographic measurement assesses the space between the distal tibia and fibula?

The tibiofibular clear space.

27. Which imaging modality is especially useful for evaluating syndesmotic ligament tears?

Magnetic resonance imaging (MRI).

28. What is the primary biomechanical consequence of syndesmotic instability?

Loss of normal ankle mortise congruence, potentially altering tibiotalar joint loading.