Ankle fractures

This ppt describes ankle fractures and its management mainly according to Lauge-hansen classification.

1. Ankle Fractures Dr. Kunal Arora PGIMS, Rohtak

2. Ankle joint anatomy Comprises of tibia, fibula and talus along with ligaments. Distal tibia metaphysis flares out to form plafond, medial malleolus and posterior malleolus . Distal fibula is called lateral malleolus and rest within the incisura - a groove on the posterolateral aspect of the tibia.

3. Ankle ligaments Lateral ligaments ATFL- Anterior talofibular ligament CFL- Calcaneofibular ligament PTFL- Posterior talofibular ligament Syndesmosis AITFL- Anterior inferior tibiofibular ligament Interosseous ligament Interosseous membrane PITFL- posterior inferior tibiofibular ligament Medial ligaments Deltoid ligament (superficial and deep component)

4. Radiographic assesment 3 views are usually done : AP view we see: Superior and medial clear space- these spaces should be equal. A larger medial space indicates talar shift and incongruent ankle joint. Limit is 5mm. Lateral ( tibiofibular ) clear space- indicates the engagement of fibula in the incisura and should also be <5mm. If larger indicates syndesmosis . Tibiofibular overlap: often cited but highly variable with rotation: usually >5mm on an AP view

5. Mortise view Taken in 20 degree of internal rotation allowing a better view of lateral joint space and lateral process of talus. Fibular nipple sign – similar to shenton’s arc in the hip, indicating that the curves of fibular and tibial articular surfaces are congruent at the mortise. Lateral clear space- consist of two parllel lines of articular surface of the fibula and lateral process of talus. Fibular shortening is best estimated as increase in lateral clear space distally just above lateral process of talus when compared to that space immediately lateral to talar dome.

6. Lateral view Talar dome should appear in perfect profile.We have to note the talus and its dome, and its congruity with the tibial plafond, as well as the posterior malleolus . Many fibular fractures are in coronal plane and easily discerned on lateral view.

7. Classification Three classification system are used mainly: Potts’s classification AO/Weber classification Lauge Hansen classification

8. Pott’s classification Unimalleolar fracture- Isolated fracture of the lateral malleolus . Bimalleolar - Involving both lateral and medial malleolus . Trimalleolar - Additionally involves posterior malleolus.

9. Weber’s classification Classified according to level of fibular fracture in relation to syndesmosis Type A- Infrasyndesmotic fractures; usually avulsion fracures after an inversion injury Type B- Trans- syndesmotic and most common type, occuring after torsional injuries Type C- Suprasyndesmotic and less common and they are more challenging in terms of reduction.

10. Lauge -Hansen classification This classification aims to describe the force vectors that produced the injury. First word describes the position of foot at the time of injury either pronation or supination and, Second word describes the movement of hindfoot either adduction, abduction or external rotaion .

11. This results in four group of injuries supination -adduction (SAD) a pure inversion injury Supination -ext. Rotaion (SER) inversion with external rotation p ronation -abduction (PAB) a pure eversion injury p ronation -external rotation (PER) eversion injury with external rotation

12. Supination -external rotation fractures SER type 1 – AITFL rupture or Chaput’s tubercle Management- It’s a stable ankle fracture (classic ankle sprain) and managed non operatively Rarely tubercle of chaput’s can be avulsed then fixed with a lag screw if there is displacement.

13. Stable ankle fractures Fractures that have a congruent mortise that will remain so during fracture healing. They include: Isolated lateral malleolus fractures Isolated avulsion fractures of fibula tip Isolated fractures of medial malleolus These fractures are treated non operatively even if there is some displacement of fracture fragment.

14. Unstable ankle fractures Where mortise is not congruent, or it could become non-congruent during healing. It include: Clinically deformed clearly or dislocated at presentation. On X-ray- there is T alar shift on mortise. Unstable fracture pattern like Bimalleolar fractures Trimalleolar fractures High fibular fractures ( weber c and maisonneuve )

15. SER type 2 AITFL rupture or Chaput’s tubercle + Oblique fibular fracture It’s a stable ankle fracture Non operative management with a weight bearing orthosis

16. SER Type 3 AITFL rupture or Chaput’s tubercle + Oblique fibular fracture + PITFL rupture or post. Malleolus fracture

17. Management Potentially unstable ankle fracture Posterior malleolus- fixed if it comprises >25% of the plafond or there is talus subluxation Fixed with AP screw or a post. Buttress plate is used Lateral malleous - if post. Malleolus requires fixation, fibula is also fixed with lag screw and 1/3 rd tubular plate

18. SER Type 4 AITFL rupture or Chaput’s tubercle + Oblique fibular fracture + PITFL rupture or post. Malleolus fracture + Oblique medial malleolus fracture or deltoid ligament rupture

19. Management Unstable ankle fracture Posterior malleolus- fixed if it comprises >25% of the plafond or there is talus subluxation . Lateral malleous - fixed with lag screw and 1/3 rd tubular plate Medial malleolus- fixed with lag screws Syndesmosis - occasionally injured, fixed with a screw.

20. Indication’s of syndesmosis fixation Fibula fracture in proximal 2/3 rd – fibula fracture does not need to be explored as it puts peroneal nerve at risk Fibula fracture in distal 3 rd with clear diastasis Fibula fracture in distal 3 rd with diastasis revealed only on intraoperative stress testing.

21. Pronation -Abduction injury PAB 1 - Transverse medial malleolus fractures or deltoid ligament tear. Management- It’s a stable ankle fracture and managed non operatively with full weight bearing orthosis . It is fixed with a lag screw if there is displacement.

22. PAB-2 Transverse medial malleolus fractures or deltoid ligament tear + AITFL rupture or Chaput’s tubercle avulsion Management- It’s a stable ankle fracture and managed non operatively with full weight bearing orthosis . Rarely tubercle of chaput’s can be avulsed then fixed with a lag screw if there is displacement

23. PAB-3 Transverse medial malleolus fractures or deltoid ligament tear + AITFL rupture or Chaput’s tubercle avulsion + Comminuted high fibular fracture

24. Management Unstable ankle fracture Lateral side-fibula is brought to length and comminution is bridged with a 3.5mm DCP or fibular nail Medial malleolus- fixed with lag screws or TBW Deltoid injuries do not require repair. Posterior malleolus- rarely involved, fixed if >25% of the plafond or there is talus subluxation . Syndesmosis - often injured, fixed with a screw after performing stress test.

25. Pronation -External rotation injuries PER 1 – Oblique medial malleolus fractures or deltoid ligament tear. Management- It’s a stable ankle fracture and managed non operatively with full weight bearing orthosis . It is fixed with a lag screw if there is displacement.

26. PER 2 Oblique medial malleolus fractures or deltoid ligament tear + AITFL rupture or Chaput’s tubercle avulsion Management- It’s a stable ankle fracture and managed non operatively with full weight bearing orthosis . Rarely tubercle of chaput’s can be avulsed then fixed with a lag screw if there is displacement

27. PER 3 Oblique medial malleolus fractures or deltoid ligament tear + AITFL rupture or Chaput’s tubercle avulsion + High fibular fracture with diastasis

28. PER 4 Oblique medial malleolus fractures or deltoid ligament tear + AITFL rupture or Chaput’s tubercle avulsion + High fibular fracture with diastasis + PITFL rupture or post. Malleolus fracture

29. Management of PER 3 and PER 4 Unstable ankle fractures Lateral side-fibula is fixed if fracture in distal 1/3 rd Medial malleolus- fixed with lag screws or TBW Deltoid injuries do not require repair. Syndesmosis - often injured, fixed with a screw after performing stress test. Posterior malleolus- involved in PER 4 , fixed if >25% of the plafond or there is talus subluxation .

30. Supination -Adduction injuries SAD Type 1- Transverse lateral malleous (avulsion) or ATFL rupture. Management- It’s a stable ankle fracture and managed non operatively with full weight bearing orthosis .

31. SAD 2 Transverse lateral malleous (avulsion) or ATFL rupture + Vertical shear fracture of medial mallolus +/- medial tibial plafond impaction. MANAGEMENT- Medial malleolus- Opened first. Marginal impaction is reduced and vertical shear fracture is butressed with a plate or 3 screws. Lateral side- fixed with 1/3 rd tubular plate or TBW.