Saddle joints have concave and convex surfaces. Identify a saddle joint of the skeleton.
A) interphalangeal joint of the finger
B) carpometacarpal joint of the phalanges
C) carpometacarpal joint of the thumb
D) metacarpophalangeal joint of the finger

Question

Quizplus · Accepted Answer

The carpometacarpal joint of the thumb is a saddle joint, as the surface of the trapezium bone that articulates with the base of the first metacarpal bone is concave, and the surface of the metacarpal bone is convex. The other options are all hinge joints, which have only one plane of movement.

Saddle Joints Have Concave and Convex Surfaces