Which term describes joints such as the knee, lumbar, scapula, lower cervical, and elbow?

• A. Mobile Joints
• B. Synarthrotic Joints
• C. Stable Joints
• D. Ball-And-Socket Joints

Answer: (C)

Mobility is what these joints share. The knee and elbow are classic examples of diarthrodial or synovial joints, designed for a wide range of motion and supported by a robust capsule, ligaments, and often additional structures like menisci or discs. The scapular region contributes to shoulder motion, and the lumbar and lower cervical joints also permit bending, twisting, and various degrees of movement. Because their defining feature is movement rather than rigid stability, the best descriptor is mobile joints.

Immovable joints (synarthroses) exist, like skull sutures, but that doesn’t describe the group here. Ball-and-socket is a specific type of mobile joint, not a universal description for all listed joints. While these joints are stabilized by ligaments, the overarching idea that characterizes them collectively is their mobility.