a shallow depression in the roof of the orbit close to the medial margin to which is attached the pulley for the superior oblique tendon.
What is trochlear fossa?
: a depression in the antero-medial aspect of each orbital plate of the frontal bone that forms a point of attachment for the corresponding superior oblique muscle .
What bone is the trochlear fossa on?
The trochlear notch (/ˈtrɒklɪər/), 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.
What is the function of the trochlear notch?
The articulation of the humeral trochlea and the trochlear notch of the ulna is the major facilitator of flexion and extension about the elbow . The radiocapitellar articulation supports motion in both the flexion and extension of the elbow in addition to supination and pronation of the forearm.
Is the trochlea the elbow?
In the human arm, the humeral trochlea is the medial portion of the articular surface of the elbow joint which articulates with the trochlear notch on the ulna in the forearm.
Why is the trochlear nerve unique?
The trochlear nerve is unique among the cranial nerves in several respects: It is the smallest nerve in terms of the number of axons it contains . It has the greatest intracranial length. It is the only cranial nerve that exits from the dorsal (rear) aspect of the brainstem.
What is the trochlea of the eye made of?
The trochlea of superior oblique is a pulley-like structure in the eye. The tendon of the superior oblique muscle passes through it. Situated on the superior nasal aspect of the frontal bone, it is the only cartilage found in the normal orbit.
What is Trochlear notch in anatomy?
In ulna. ...large C-shaped notch—the semilunar, or trochlear, notch— which articulates with the trochlea of the humerus (upper arm bone) to form the elbow joint .
What is the Trochlea in anatomy?
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 .
What is a radius bone?
The radius is one of the two bones that make up the forearm , the other being the ulna. It forms the radio-carpel joint at the wrist and the radio-ulnar joint at the elbow. It is in the lateral forearm when in the anatomical position. It is the smaller of the two bones.
What does the Trochlear notch look like?
The notch is concave from above downward , and divided into a medial and a lateral portion by a smooth ridge running from the summit of the olecranon to the tip of the coronoid process. The medial portion is the larger, and is slightly concave transversely; the lateral is convex above, slightly concave below.
What shape is the trochlea?
The trochlea is the roughly hourglass-shaped feature on the distal end of the humerus. It articulates with the trochlear notch of the ulna. The head of the radius articulates with the capitulum of the humerus, the ball-shaped feature just lateral to the trochlea.
Where is the radial notch located?
The Upper Limb
Proximally, the radial notch is located on the lateral side . In the shaft, the sharp interosseous border is lateral. The nutrient foramen is usually in the centre of the anterior upper half with its entrance directed proximally. Distally, the medial surface is slightly concave.
What forms the tip of the elbow?
An olecranon (oh-LEK-rah-nun) fracture is a break in the bony “tip” of the elbow. This pointy segment of bone is part of the ulna, one of the three bones that come together to form the elbow joint.
What is the difference between trochlea and capitulum?
is that capitulum is (botany) a densely clustered inflorescence composed of a large number of individual florets arising from a platform-like base while trochlea is (anatomy) structure resembling a pulley , typically in reference to the area connecting the upper and lower arm.
Which movement of the elbow is the radius involved in?
Bones and Joints of the elbow joint
The Radius is the smaller bone of the forearm situated on the outer surface of the joint. The head of the radius is circular and hollow which allows movement with the humerus. The connection between the ulna and radius helps the forearm to rotate .
