How many primary classifications of joints are there?

The correct answer reflects the established classification in anatomy and kinesiology, where joints are primarily classified into three categories: fibrous, cartilaginous, and synovial.

Fibrous joints are connected by dense connective tissue and generally allow for little to no movement, such as those found in the skull. Cartilaginous joints, which provide slightly more flexibility, are connected by cartilage and include joints like the intervertebral discs in the spine. Synovial joints are the most common and allow for a wide range of movement, featuring a fluid-filled joint capsule, with examples including the knee and elbow.

Understanding these primary classifications helps in evaluating the mechanics of movement and injury risk in running and other physical activities, emphasizing the importance of proper joint health for overall athletic performance.