Which joint is formed by the humerus and ulna at the elbow?

Which joint is formed by the humerus and ulna at the elbow?

• A. Shoulder
• B. Elbow
• C. Wrist
• D. Hip

Answer: (B)

At the elbow, the joint is formed where the distal humerus meets the proximal ulna, creating the humeroulnar joint. This hinge-shaped articulation allows bending and straightening of the forearm. The ulna’s trochlear notch fits onto the humeral trochlea, providing the primary stability for the elbow. The radius also engages with the humerus at the elbow (and with the ulna via the proximal radioulnar joint) to enable forearm rotation, but the direct humerus–ulna contact defines the elbow itself. Regions involving the shoulder, wrist, and hip use different bone connections: the shoulder pairs the humerus with the scapula and clavicle, the wrist involves the radius with the carpal bones, and the hip involves the femur with the pelvis.

At the elbow, the joint is formed where the distal humerus meets the proximal ulna, creating the humeroulnar joint. This hinge-shaped articulation allows bending and straightening of the forearm. The ulna’s trochlear notch fits onto the humeral trochlea, providing the primary stability for the elbow. The radius also engages with the humerus at the elbow (and with the ulna via the proximal radioulnar joint) to enable forearm rotation, but the direct humerus–ulna contact defines the elbow itself. Regions involving the shoulder, wrist, and hip use different bone connections: the shoulder pairs the humerus with the scapula and clavicle, the wrist involves the radius with the carpal bones, and the hip involves the femur with the pelvis.