The pivot joint between atlas and axis is a type of

Options

A. fibrous joint
B. cartilaginous joint
C. synovial joint
D. saddle joint

Answer

To determine the type of joint between the atlas and axis, we need to analyze the options given and understand the characteristics of the joints mentioned.

### Step-by-Step Solution:

1. **Identify the Joints**: The atlas (C1) and axis (C2) are the first two cervical vertebrae in the human spine. They play a crucial role in the movement of the head.

2. **Understand Joint Types**:
- **Trapezoid Joint**: This is not a recognized type of joint in human anatomy.
- **Cartilaginous Joint**: These joints are characterized by the presence of cartilage and allow for slight movement. They are found between vertebrae.
- **Synovial Joint**: These joints are freely movable and allow for a wide range of motion in various directions.
- **Saddle Joint**: A type of synovial joint that allows for movement in two planes, found in the thumb.

3. **Analyze the Movement**: The joint between the atlas and axis allows for rotation of the head, which is more than just slight movement. This indicates that it is not a cartilaginous joint.

4. **Determine the Correct Answer**: The joint between the atlas and axis is classified as a **synovial joint**, specifically a pivot joint, which allows for rotational movement.

### Final Answer:
The pivot joint between the atlas and axis is a type of **synovial joint**.

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