What is primarily associated with synarthroses joints?

Synarthroses joints are characterized by their immobility, meaning that they do not allow any movement between the bones they connect. This type of joint is vital for providing stability and strength to the skeletal system. Examples of synarthroses include sutures in the skull, where the bones are tightly bound together to protect the brain and maintain the shape of the head.

In contrast, joints that allow free movement are classified differently, such as diarthroses, while those offering slight movement are referred to as amphiarthroses. Excessive mobility is not a characteristic of any joint type that emphasizes stability; rather, it can lead to joint issues. Therefore, the defining feature of synarthroses lies in their lack of movement, aligning with the correct answer.