Which of the following joints is an example of a symphysis joint?

• A. Elbow joint
• B. Knee joint
• C. The joint between the bodies of two vertebrae
• D. Shoulder joint

Answer: (C)

A symphysis joint is characterized by the presence of a fibrocartilaginous pad or disc that serves as a cushion between the bones, allowing for limited movement while also providing stability. The joint between the bodies of two vertebrae exemplifies a symphysis joint because it features intervertebral discs made of fibrocartilage that sit between the vertebral bodies. This design permits slight flexibility and movement of the spine while also acting as a shock absorber to protect the spinal column during activities such as bending and twisting.

In contrast, the elbow and shoulder joints are examples of synovial joints, which allow for a greater range of motion due to their structure involving a joint capsule and synovial fluid. The knee joint, while also a synovial joint, is specifically classified as a hinge joint, which primarily allows for flexion and extension. Therefore, the correct identification of the joint between the bodies of two vertebrae as a symphysis highlights its unique structural properties that differentiate it from the more mobile and complex synovial joints.