The articulation between the head of the femur and the acetabulum is which type of joint?

The articulation between the head of the femur and the acetabulum is which type of joint?

• A. Ball and socket joint
• B. Pivot joint
• C. Hinge joint
• D. Saddle joint

Answer: (A)

A ball-and-socket arrangement best fits the hip joint. The head of the femur is a rounded ball that fits into the cup-shaped acetabulum of the pelvis, forming a ball-and-socket synovial joint. This setup allows movement in multiple directions: flexion and extension, abduction and adduction, internal and external rotation, and even circumduction. The joint is stabilized by the deep socket, the acetabular labrum, and a strong fibrous capsule with reinforcing ligaments. Other joints described would not permit the same range of spherical movement. A pivot joint rotates around a single axis, a hinge joint mainly bends in one plane, and a saddle joint allows two directions of movement but not the full ball-in-cup rotation.

A ball-and-socket arrangement best fits the hip joint. The head of the femur is a rounded ball that fits into the cup-shaped acetabulum of the pelvis, forming a ball-and-socket synovial joint. This setup allows movement in multiple directions: flexion and extension, abduction and adduction, internal and external rotation, and even circumduction. The joint is stabilized by the deep socket, the acetabular labrum, and a strong fibrous capsule with reinforcing ligaments.

Other joints described would not permit the same range of spherical movement. A pivot joint rotates around a single axis, a hinge joint mainly bends in one plane, and a saddle joint allows two directions of movement but not the full ball-in-cup rotation.