NUCCA Biomechanics
By Takanobu Nakaseko
Review of Misalignment Types
Type1 Misalignment
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
Type2 Misalignment
Characteristics
- 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
Type3 Misalignment
Characteristics
- C1 laterality on the same side of
skull tipping
- No angular rotation
- C1 remains fairly horizontal
- Laterality produced by skull tipping
Directl
y by
Skull
Side of
Laterality
Type4 Misalignment
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
SUMMARY
Acute Angle
Cause
Type 1
Contralateral
C1 Sideslip
Type 2
Ipsilateral
Head tilt
Type 3
Type 4
Contralateral
Head tilt
C1 sideslip /
Head tilt
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.
Head Piece
Mastoid Process
Mechanism of Head Piece
Skull COG on the B
Mechanism of Head Piece
Skull COG on the C
Mechanism of Head Piece
Skull COG on the A
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
C/A?
C/A?
C/A?
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.
Type 1 Correction
Type 1 Correction
Type 2 Correction
Type 2 Correction
Type 3 Correction
Type 3 Correction
Type 4 Correction
Type 4 Correction