1. Detecting factors of Syndesmotic injury in Ankle Fx. in radiograph
분당서울대학교병원 최 영

2. Ankle Fracture
Indrect ankle Fx.
One of the most common injury on OS

3. Ankle Anatomy

4. Ankle Anatomy

5. Ankle Fracture Lauge-Hansen Classification
Pronation : abd, eversion, DF
Supination : add, inversion, PF

6. Ankle Fracture Lauge-Hansen Classification
Supination - External Rotation
Supination Addution
Pronation - External Rotation
Pronation Addution
40-75%

7. Ankle Fracture Lauge-Hansen Classification
Supination - External Rotation
Supination Adduction
Pronation - External Rotation
Pronation Addution
10-20%
(I) a low avulsion fracture of the lateral malleolus
or lateral ligament injury; and (II) a vertical shear fracture of the medial malleolus (Fig. 3).
This pattern is also associated with an impaction injury to the medial tibial plafond.6

8. Ankle Fracture Lauge-Hansen Classification
Supination - External Rotation
Supination Addution
Pronation - External Rotation
Pronation Addution
5-20%

9. Ankle Fracture Lauge-Hansen Classification
Supination - External Rotation
Supination Addution
Pronation - External Rotation
Pronation Addution
7-15%

10. SER type

11. Syndesmosis injury
a joint in which the bones are united by fibrous connective tissue forming an interosseous membrane or ligament.
A syndesmosis is slightly movable articulation where the contiguous bony surfaces are united by an interosseous ligament or membrane as in the inferior tibiofibular articulation

12. Hypothesis
Bony attenuation vs Syndesmosis

13. Hypothesis
Bony attenuation vs Syndesmosis

14. Patients Patents : ankle Fx. c OP in our hospital Inclusion Exclusion
From Mar to Feb. 2013
1109 cases
Inclusion
SER type
Preoperative X-ray, 3D-CT
Exclusion
Direct injury, anatomical deformity
Inadequate radiography

15. Measurement Method
3-Dimension CT
X-ray (Mortise view)

16. Radiographic measurement
Fracture height
Fracture length
Medial joint space
Bony attenuation
Age
Gender
Injury mechanism

17. Fracture height

18. Medial joint space

19. Fracture length

20. Bony attenuation (Lat. Malleolus)

21. Bony attenuation (Med. Malleolus)

22. Bony attenuation (Talus)

23. Ankle Mortise view

24. Fracture height
leg internally rotated 15 to 20 deg so that x-ray beam is nearly perpendicular to the intermalleolar line.

25. Medial joint space

26. Statistical Method median, interquatile range(IQR) and proportions
Kolmogogrov-Smirnov test
Univariate analyses (Mann-Whitney U test or chi- square exact test)
receiver operating characteristic (ROC) curve
Delong’s test
detect the significant of the area under the curve (AUC)

27. Result SER type ankle Fx. : total 191 patients
Male : Female = 104 : 87
Mean age = 53.2±15.2 years (range 18-85)
Syndesmotic injury (+) : 38 patients
Syndesmotic injury (-) : 153 patients

28. Result : CT Fracture height Medial joint spaces
Syndesmotic injury (+) : 13.89±17.36
Syndesmotic injury (- ) : -0.87±6.95
P-value < 0.001
Medial joint spaces
Syndesmotic injury (+) : 5.58±3.48
Syndesmotic injury (- ) : 3.41 ±1.55

29. Result : CT Medial joint spaces Fracture length
Syndesmotic injury (+) : ±91.03
Syndesmotic injury (- ) : ±94.69
P-value < 0.001
Fracture length
Syndesmotic injury (+) : 37.45±13.57
Syndesmotic injury (- ) : ±11.63
P-value =0.232

30. Result : CT
AUC : 0.765
AUC값이 00이상으로 유의하게 나왔다

31. Result : CT
AUC : 0.731

32. Result : CT
AUC : 0.753

33. Result : CT Fracture height Medial joint spaces
Syndesmotic injury (+) : ±18.79
Syndesmotic injury (- ) : -1.28±7.22
P-value < 0.001
Medial joint spaces
Syndesmotic injury (+) : 5.84±3.39
Syndesmotic injury (- ) : 3.34±1.49

34. Result : CT
AUC : 0.569

35. Result : X-ray
AUC : 0.779

36. Result : X-ray
AUC : 0.726

37. Conclusion SER type Ankle Fx. X-ray CT frature height > 7mm
Medial joint space > 4.5mm CT
Fracture height > 3mm
Medial joint space > 4.9mm
Bony attenuation > 262.7

38. Conclusion Consideration of treatment on Ankle Fx.
Predictive Factors of Syndesmotic injury

39. Thank you for your attention

40. Discussion X-ray, CT Limitation Factors to detect syndesmotic injury
Retrospective study
Technical problem in radiograph