1. NUCCA Biomechanics
By Takanobu Nakaseko

2. Review of Misalignment Types

3. Type1 Misalignment Side of Laterality Characteristics
- C1 laterality on the same side of
angular rotation
- Contralateral acute angle
- Skull is parallel to vertical axis
- C1 is above parallel
Side of Laterality

4. Type2 Misalignment Side of Laterality Characteristics Mainly by Skull
- C1 laterality on the opposite side of
angular rotation
- Ipsilateral acute angle
- Skull is tipped toward vertical axis
- C1 remains fairly horizontal
- Laterality produced mainly by skull
Mainly by
Skull
Side of Laterality

5. Type3 Misalignment Side of Laterality Directly by Skull
Characteristics
- C1 laterality on the same side of
skull tipping
- No angular rotation
- C1 remains fairly horizontal
- Laterality produced by skull tipping
Directly by
Skull
Side of Laterality

6. Type4 Misalignment Side of Laterality Characteristics
- C1 laterality on the same side of
angular rotation
- Contralateral acute angle
- Skull is tilted away from vertical axis
- C1 is above parallel
Side of Laterality

7. SUMMARY Acute Angle Cause Type 1 Type 2 Type 3 Type 4 Contralateral
C1 Sideslip
Type 2
Ipsilateral
Head tilt
Type 3 -
Type 4
C1 sideslip / Head tilt

8. How to Correct Misalignment?
Combination of the Head piece placement and Triceps pull
Patient placement is extremely crucial!
Using 3-D Xray (Lateral, Nasium, Vertex) to analyze how to set the patient on the table and specific correction vector.

9. Head Piece A B C D

10. Mastoid Process 1 4
2/3

11. Mechanism of Head Piece Skull COG on the B

12. Mechanism of Head Piece Skull COG on the C

13. Mechanism of Head Piece Skull COG on the A

14. C/A? Condylar circle over Axial circle
C/A is the specific vector which allows both condylar circle and axial circle to rotate the same distance, but different speed.
C/A is unique to each individual
Can be calculated. C/A=(A-C)/2

15. C/A?
Condylar Circle
Lever
Axial Circle

16. C/A?

17. C/A?
C/A

18. C/A?
Type 1
The vector is always higher than C/A in order to affect lower angle.
Type 2&3
The vector is always lower than C/A in order to affect head tilt.
Type 4
The vector is close to C/A because both lower angle and head tilt should be corrected at the same time.

19. Type 1 Correction

20. Type 1 Correction
COG B

21. Type 2 Correction

22. Type 2 Correction
COG D

23. Type 3 Correction

24. Type 3 Correction
COG D

25. Type 4 Correction

26. Type 4 Correction
COG C