trochlea

anatomy

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July 14, 2026

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The trochlea is an anatomical structure that resembles a pulley. In human anatomy, it is specifically the spool-shaped articular surface located on the medial condyle of the humerus, the bone of the upper arm. This trochlea fits into a notch in the ulna, one of the bones of the forearm, forming a crucial part of the elbow joint. This articulation allows for the bending and extension of the forearm. The term "trochlea" originates from the Latin word for a block of pulleys, reflecting its pulley-like shape and function in joint movement.123

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humerus
…smooth articular surfaces (capitulum and trochlea), two depressions (fossae) that form part of the elbow joint, and two projections (epicondyles). The capitulum laterally articulates with the radius; the trochlea, a spool-shaped surface, articulates with the ulna. The two depressions—the olecranon fossa, behind and above the trochlea, and the coronoid fossa,…
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…smooth articular surfaces (capitulum and trochlea), two depressions (fossae) that form part of the elbow joint, and two projections (epicondyles). The capitulum laterally articulates with the radius; the trochlea, a spool-shaped surface, articulates with the ulna. The two depressions—the olecranon fossa, behind and above the trochlea, and the coronoid fossa,…
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