CBP CBP Spinal Physics and Mechanics 1 — Questions and Answers
Question 1: In CBP, the normal cervical lordosis measured on a lateral radiograph is approximately how many degrees?
- 17 degrees
- 34 degrees (Correct answer)
- 42 degrees
- 60 degrees
Correct answer: 34 degrees
CBP establishes the normal cervical lordosis as approximately 34 degrees (Cobb angle C2–C7) based on geometric modeling of ideal spinal curvature.
Question 2: Which mathematical model does CBP use to describe the ideal spinal curvature?
- Fibonacci spiral
- Circular arc or Harrison posterior tangent method (Correct answer)
- Parabolic curve
- Elliptical model
Correct answer: Circular arc or Harrison posterior tangent method
CBP uses the circular arc model (Harrison posterior tangent method) to quantify and compare spinal curvatures to an ideal geometric standard.
Question 3: What does the term 'antalgic posture' mean in CBP spinal mechanics?
- A posture adopted to reduce pain by shifting spinal loading (Correct answer)
- The ideal upright posture with balanced spinal curves
- A posture caused by leg length inequality alone
- A normal postural variant requiring no treatment
Correct answer: A posture adopted to reduce pain by shifting spinal loading
An antalgic posture is one the body assumes to offload a painful structure, often resulting in lateral or sagittal imbalances that CBP aims to correct.
Question 4: In CBP, what is the primary mechanical consequence of a loss of cervical lordosis?
- Reduced cervical rotation range of motion only
- Increased compressive loading on anterior disc structures (Correct answer)
- Decreased intervertebral foramen size at all levels
- Improved shock absorption through the spine
Correct answer: Increased compressive loading on anterior disc structures
Loss of cervical lordosis shifts the head's center of gravity anteriorly, dramatically increasing compressive and shear forces on anterior disc and vertebral body structures.
Question 5: The 'mirror image' principle in CBP refers to which treatment concept?
- Using bilateral spinal adjustments simultaneously
- Positioning the patient in the exact opposite of their postural deformity during treatment (Correct answer)
- Replicating the patient's posture on a mannequin for analysis
- Applying equal force on both sides of the spine
Correct answer: Positioning the patient in the exact opposite of their postural deformity during treatment
The mirror image principle means the corrective exercise, traction, or manipulation posture is the precise geometric opposite of the patient's measured postural deviation.
Question 6: Which law of physics is most directly applied in CBP when calculating the moment arm effect of forward head posture?
- Newton's First Law of Inertia
- Hooke's Law of Elasticity
- Lever mechanics (torque = force × distance) (Correct answer)
- Bernoulli's Principle
Correct answer: Lever mechanics (torque = force × distance)
CBP applies lever/torque mechanics: as the head translates anteriorly, the moment arm increases, multiplying the effective load on the cervical spine proportionally.
CBP CBP Spinal Physics and Mechanics 1
In CBP, the normal cervical lordosis measured on a lateral radiograph is approximately how many degrees?