Search results
Results from the WOW.Com Content Network
During elbow flexion, the vertical anterior part of the trochlea keeps the upper arm and forearm aligned (when viewed in front). During elbow extension, however, the oblique posterior part makes contact with the trochlear notch on the ulna so that this obliquity forces the main axis of the forearm to form a small angle with that of the upper arm.
The humeroulnar joint (ulnohumeral or trochlear joint [1]) is part of the elbow-joint. It is composed of two bones, the humerus and ulna, and is the junction between the trochlear notch of ulna and the trochlea of humerus. [1] It is classified as a simple hinge-joint, which allows for movements of flexion, extension and circumduction.
The trochlear notch (/ ˈ t r ɒ k l ɪər /), [1] also known as semilunar notch and greater sigmoid cavity, is a large depression in the upper extremity of the ulna that fits the trochlea of the humerus (the bone directly above the ulna in the arm) as part of the elbow joint. It is formed by the olecranon and the coronoid process.
The elbow is the region between the upper arm and the forearm that surrounds the elbow joint. [1] The elbow includes prominent landmarks such as the olecranon , the cubital fossa (also called the chelidon, or the elbow pit), and the lateral and the medial epicondyles of the humerus .
The radius can thus glide on the capitulum during elbow flexion-extension while simultaneously rotate about its own main axis during supination-pronation. [2] Between the capitulum and the trochlea of the humerus is the capitulotrochlear groove. A semi-lunar surface around the circumference of head is shaped to articulate continuously with this ...
The coronoid fossa is smaller than the olecranon fossa and receives the coronoid process of the ulna during maximum flexion of the elbow. Coronoid fossa of the humerus Above the front part of the capitulum is a slight depression, the radial fossa , which receives the anterior border of the head of the radius, when the forearm is flexed.
Is a simple hinge-joint, and allows of movements of flexion and extension only. Humeroradial joint: head of the radius: capitulum of the humerus: Is a ball-and-socket joint. Superior radioulnar joint: head of the radius: radial notch of the ulna: In any position of flexion or extension, the radius, carrying the hand with it, can be rotated in it.
Superior to the anterior portion of the trochlea is a small depression, the coronoid fossa, which receives the coronoid process of the ulna during flexion of the forearm. It is directly adjacent to the radial fossa of the humerus .