1. Internal Fixation of Ankle Fractures
6-10 1

2. Objectives Review ankle anatomy
Identify the indications & treatment goals for ORIF of ankle fractures
Summarize the implant options

3. Anatomy Ankle Bones
Formed by medial malleolus of tibia, and lateral malleolus (fibula)
Talus sits in “mortise” (as in “mortise & tenon”)
Fibula
Tibia
Talus

4. Anatomy Ankle Soft Tissues
Ligaments connect ankle on medial & lateral sides
Important for stability

5. Anatomy Ankle Soft Tissues
Fibula connected to tibia by fibrous band of tissue called syndesmosis
Also important for stability

6. Ankle Fractures 1

7. Ankle Fractures History Physical examination Twisting injury
Immediate pain – lateral and/or medial
Difficulty weight-bearing
Physical examination
Malleolar pain (posterior & anterior)
Swelling
Neurovascular involvement

8. Ankle Fractures Radiographs
Ankle Series: AP, mortise, lateral
“Rule out” other injuries:
Osteochondral injuries
Lateral process fracture
Anterior calcaneus fracture
Base of 5th MT fracture AP
Mortise
Lateral

9. Ankle Fractures Classification
Weber / AO Classification based on level of fibula fracture
A – Below syndesmosis
B – At syndesmosis
C – Above syndesmosis

10. Simple Classification: Stable & Unstable
Stable fractures
Most commonly involve medial or lateral side only
Talus remains anatomic relative to tibia

11. Simple Classification: Stable & Unstable
Unstable fractures
Disruption of 2 or more aspects of the mortise -- bone and/or ligament
Talus may sublux or be dislocated from tibia

12. Stable Examples

13. Unstable Examples

14. Indications for Surgery Ankle Fractures
Inability to obtain or maintain an anatomic mortise (unstable fracture pattern)
Open fractures

15. Basic Set-Up Ankle Fractures
Supine position most common
Occasionally prone for direct approach to posterior malleolus
Bump beneath ipsilateral buttocks (allows easier approach to fibula)
Tourniquet
Prep / drape to above knee
Pre-op antibiotics
Fluoroscopy or X-ray

16. General Considerations
Small size of ankle bones = dictates implant sizes
Multiple complex 3-D articulations
Weight bearing structure subject to high stresses (2 – 5x body weight)

17. General Considerations
Limited soft tissue coverage

18. Instrumentation Ankle Fractures
Small fragment set
Cannulated screws
K-wires
Cerclage wire
Power
Have mini-frag available

19. Ankle Fracture Surgical Tx
Type
One malleolus
Bimalleolar
Tri-malleolar
Treatment
Fix fibula with screw / TB wire / plate
Plate fibula, lag screw tibia (medial malleolus)
Plate fibula, lag screw tibia, fix posterior if > % articular surface involved

20. Implant Considerations Lateral Malleolus
One-third tubular plate & mm cortex screws
Lateral
Posterior
3.5mm compression plate for unstable fractures

21. Implant Considerations Lateral Malleolus
Locking plates -- lateral or posterolateral
Osteoporotic bone
Unstable fractures
Distal fractures

22. Implant Considerations Lateral Malleolus
Hook Plate
Used to obtain purchase in very distal fibula fractures

23. Implant Considerations Posterior Malleolus
Posterior to anterior Anterior to posterior

24. Implant Considerations Medial Malleolus
Two partially threaded 4.0 mm cancellous screws
K-wires
Cerclage wire for tension band technique

25. Syndesmosis Fixation Indications
Syndesmotic instability after fixation of malleolus
Consider if fibula fracture > 4 cm above joint line & Maisonneuve’s fracture
Have bone hook on back table to check stability
Have large frag screws & instruments available

26. Implant Considerations Syndesmosis
Surgeons choice of large or small fragment fully threaded screws, one or two
Not inserted as lag screw, but as a positioning screw (threads engage all cortices)
Secures position of fibula next to tibia allowing torn syndesmotic tissues to heal
May be removed in weeks

27. Implant Considerations Syndesmosis
Have pelvic forceps on back table
May need longer plates than in small frag set:
1/3 tubular, compression or specialty fibula plate
Bioresorbable screws

28. Case #1 Age: 81 Gender: Female Cause of Injury: Fall
Fixation: 3.5mm LCP Lateral
Distal Fibula Plate

29. Case #2 Age: 64 Gender: Female Cause of Injury: Fall
Fixation: 3.5mm LCP Lateral
Distal Fibula Plate

30. Summary Reviewed ankle anatomy
Identified the indications & treatment goals for ORIF of ankle fractures
Summarized the implant options

31. Thank You