Ankle Fractures

1. Ankle Fractures OTA Fracture Course

2. Significance of Ankle Fractures Most common weight bearing fracture we will treat Incidence is increasing Something we will all encounter

3. Lateral Ligaments

4. Medial Ligaments

5. Syndesmosis

6. Instability • Inability to keep talus perfectly positioned under plafond • Usually lateral direction (external rotation) • Primary stabilizer is the deep deltoid JBJS 78, 1024

7. How much is too much • 1 mm translation  decrease contact area by 42% JBJS 58,356

8. Indications for surgery • Instability of talus • Dynamic incongruity • Plafond step-off • Static iincongruity

9. X-ray • AP, Lateral and Mortise views of the ankle • AP and lateral of tibia • Consider stress views

10. Overlap Tilt Anteroposterior View

11. Mortise View Overlap Tilt Medial clear space

12. Posterior malleolus fracture Subluxation of the talus Distal fibula fx Lateral View

13. Classification • Lauge-Hansen • Danis-Weber (AO)

14. Danis-Weber Classification Doesn’t address the medial injury

15. (Over)simplified

16. Weber A • Supination-Adduction

17. Weber B • Supination-ER • With or without deltoid

18. Weber C • Pronation-ER • Pronation-Abduction

19. Maisonneuve Fx

20. Treatment

21. Medial Malleolar Fractures • Nondisplaced fractures may be treated nonoperatively • Displaced fractures • Isolated ?? ORIF • Part of bimalleolar pattern  ORIF • Horizontal (tension)  compression • Vertical (shear)  antiglide plate

24. Other compression options for medial side

25. Vertical (shear) medial fractures

26. Vertical (shear) medial fractures

28. Lateral Malleolus Fractures Nonoperative management • 2-3 mm displacement • NO medial widening or syndesmotic injury • Cast or boot immobilization 6 wks • WBAT • Follow closely! • Stress view to ensure no medial injury ???

29. Surgical Indications • Bimalleolar / trimalleolar fractures • Bimalleolar equivalent • Syndesmotic disruption • Talarsubluxation

30. Implant ConsiderationsLateral Side • One-third tubular • “neutralization” plate laterally • “antiglide” plate posteriorly • 3.5 LCDCP on shaft

31. Other options forlateral side

32. Other options forlateral side

33. Posterior Malleolus • > 25% rule • Based on nothing • Fix if ANY posterior subluxation • A  P or P  A • Prone position very helpful

34. Biomechanics - Syndesmosis • Gardner 2006 • Compared fixation of syndesmosisvs posterior malleolus ORIF • Syndesmosis fixed= 40% of normal • Posterior malleolus fixed = 70% of normal

35. Maissoneuve Fracture • Fracture of proximal fibula • +/- medial malleolar fracture • Pronation-external rotation • Requires reduction and stabilization of syndesmosis

36. Maissoneuve Fracture • Fracture of proximal fibula • +/- medial malleolar fracture • Pronation-external rotation • Requires reduction and stabilization of syndesmosis

38. Syndesmosis Fixation • MUST test for Syndesmotic instability after fixation of lateral malleolus • Have bone hook on table to check stability, Cotton Test

39. Syndesmosis Controversies No significant difference !! 1 vs. 2 screws 3.5 vs. 4.5 screws 4 cortices vs. 3 Two hole plate Tightrope The key is the REDUCTION !!

40. THE END

41. Biomechanics • Complex motion • 5x body weight in stance • At least 10 degrees of dorsiflexion is needed for normal gait • 1 mm of lateral talar shift decreases tibiotalar surface contact up to 40%

42. (Over)simplified

43. MM LM Talus INVERSION Weber A Tibia IOM Fibula Tib-Fib Lig Delt Lig Talo-Fib Lig

44. MM LM Talus EVERSION Weber B Tibia IOM Fibula Tib-Fib Lig Delt Lig Talo-Fib Lig

45. MM LM Talus EVERSION Weber C Tibia IOM Fibula Tib-Fib Lig Delt Lig Talo-Fib Lig