Mechanistic classification of complex fracture - dislocation of the elbow

1. Acute elbow injury
Sumroeng Neti, M.D.
Orthopaedic center
Bumrungrad International Hospital

2. LCL complex
 4 bundles
1. LUCL
2. RCL
3. Annular ligament
4. Accessory LCL

3. Medial collateral ligament

4. Medial collateral ligament

5. “Biomechanical study of elbow ligaments”
Regan WD et al. Clin Orthop 1991 ;271:170-9
Tensile strength (N)
MCL anterior band 261
MCL posterior band 159
LCL 233
Palmaris longus 358
Anterior band of MCL is the strongest

6. Biomechanical of the elbow
Andrew A.Amis : Prof.of Orthopaedic Biomechanics
 MCL complex is more important than LCL
complex for functional stability
 Because the carrying angle biases the
loading towards valgus
 Anterior band of MCL is the strongest
elbow ligament
 Anterior band of MCL is isometric
 It is an important elbow stabilizer at all
angles of elbow flexion

7. Synovial membrane – Ant.

8. Synovial membrane – Post.

9. 5/21/2014 menu
Proximal R-U
joint
Radial notch
of ulna

10. Pattern of injuries
 Valgus instability
 Varus instability
 Olecranon #-dislocation
 Anterior #-dislocation
 Posterior Olecranon #-dislocation (Monteggia
lesion)

12. Valgus instability

13. Valgus instability
 Valgus + axial load
 #radial head
 Pure valgus  MCL injury
(overhead throwing athletes)
 Valgus + axial load + ext.rotation
 PLRI : elbow dislocation (Horii circle)
 Valgus + axial load + ext.rotation
 PLRI : elbow # - dislocation
+/- #radial head, +/- #coronoid

14. Valgus instability
 Valgus + axial load
Compressive failure  #radial head

15. Valgus instability
 Valgus + axial load
Compressive failure  #radial head

16. Valgus + axial load
 #radial head

17. Valgus + axial load
 #radial head

18. Valgus instability
 Pure valgus  MCL injury
Distractive failure
(overhead throwing athletes)

19. Valgus instability
 Pure valgus  MCL injury
Distractive failure
(overhead throwing athletes)

20. Valgus instability
 Pure valgus  MCL injury
Distractive failure
(overhead throwing athletes)

21. Surgical repair is performed by placing two limbs of a running, locked number-2
nonabsorbable suture through the substance of the medial collateral ligament. Drill-holes are
prepared at the footprint of the medial collateral ligament on the medial epicondyle with an
anterior and a posterior bone tunnel

22. Fig. 5-B The sutures are tied over the bone bridge with the elbow held in slight varus and
flexion.

23. Surgical Technique
 The avulsed flexor-pronator tendon
was repaired to the residual tendon
with use of
interrupted figure-of-eight
nonabsorbable sutures.
 Finally, the ulnar nerve was
transposed anteriorly with use of a
fascial sling.

26. Valgus instability
 Valgus + axial load
 #radial head
 Pure valgus  MCL injury
(overhead throwing athletes)
 Valgus + axial load + ext.rotation
 PLRI : elbow dislocation (Horii circle)
 Valgus + axial load + ext.rotation
 PLRI : elbow # - dislocation
+/- #radial head, +/- #coronoid

27. PLRI : PosteroLateral
Rotational Instability
 Valgus + axial load + ext.rotation
 PLRI : elbow dislocation
 Horii circle
 Stage 1 : disrupted LUCL
= PLRI
 Stage 2 : A-P capsule
= Perched
 Stage 3 : disrupted MCL
= Dislocation

28. PLRI : PosteroLateral
Rotational Instability
 Valgus + axial load + ext.rotation
 PLRI : elbow dislocation

29. PLRI : PosteroLateral
Rotational Instability
 Valgus + axial load + ext.rotation
 PLRI : elbow dislocation

30. Valgus instability - PLRI
 Valgus + axial load + ext.rotation
 PLRI : elbow # - dislocation
+ #radial head

31. Valgus instability - PLRI
 Valgus + axial load + ext.rotation
 PLRI : elbow # - dislocation
+ #radial head

32. Valgus instability - PLRI
 Valgus + axial load + ext.rotation
 PLRI : elbow # - dislocation
+ #coronoid

33. ORIF # coronoid process

35. Valgus instability - PLRI
 Valgus + axial load + ext.rotation
 PLRI : elbow # - dislocation
+ #radial head, #coronoid = Terrible triad

36. Terrible triad

38. Pattern of injuries
 Valgus instability
 Varus instability
 Olecranon #-dislocation
 Anterior #-dislocation
 Posterior Olecranon #-dislocation (Monteggia
lesion)

39. Varus instability

40. Varus instability : PMRI
 Varus + axial load (+/- int.rotation)
 elbow #-subluxation
Stage 1  #coronoid (anteromedial facet)
Stage 2  LCL disruption

42. Varus instability : PMRI
Stage 1 :Coronoid # (anteromedial facet)
 elbow subluxation

43. Minor coronoid # ?

44. Varus instability : PMRI
Stage 2 :Coronoid # + LCL disruption
 elbow subluxation

45. Thank you