Humerus and Ulna Flashcards
Humerus
the bone of the upper arm or forelimb, forming joints at the shoulder and the elbow
Humerus head
At the shoulder, the head of the humerus articulates with the glenoid fossa of the scapula
anatomical neck (humerus)
obliquely directed, forming an obtuse angle with the body of the humerus. in the upper half it is represented by a narrow groove separating the head of the humerus from the two tubercles, affords attachment to the articular capsule of the shoulder-joint
greater tubercle
situated lateral to the head of the humerus and posterolateral to the lesser tubercle. Its upper surface is rounded and marked by three flat impressions
lesser tubercle
although smaller, is more prominent than the greater tubercle: it is situated in front, and is directed medially and anteriorly
intertubercular groove
the deep groove that divides the greater and lesser tubercles
deltoid tuberosity
a rough, triangular area on the anterolateral (front-side) surface of the middle of the humerus to which the deltoid muscle attaches
lateral epicondyle
a small, tuberculated eminence, curved a little forward, and giving attachment to the radial collateral ligament of the elbow-joint, and to a tendon common to the origin of the supinator and some of the extensor muscles
medial epicondyle
gives attachment to the ulnar collateral ligament of elbow joint, to the Pronator teres, and to a common tendon of origin (the common flexor tendon) of some of the Flexor muscles of the forearm
sulcus for ulnar nerve
groove for ulnar nerve: a shallow vertical groove on the posterior surface of the medial epicondyle of the humerus for the ulnar nerve; called also ulnar groove
capitulum
the small rounded eminence on the lateral half of the distal end of the humerus for articulation with the radius
trochlea
the medial portion of the articular surface of the elbow joint which articulates with the trochlear notch on the ulna in the forearm
coronoid fossa
a small depression superior to the anterior portion of the trochlea, which receives the coronoid process of the ulna during flexion of the forearm
olecranon fossa
a deep triangular depression on the posterior side of the humerus, superior to the trochlea, in which the summit of the olecranon is received during extension of the forearm
supra condular ridge
either of two ridges above the condyle of the humerus of which one is situated laterally and the other medially and which give attachment to muscles
Ulna
the thinner and longer of the two bones in the human forearm, on the side opposite to the thumb
semilunar notch (ulna)
narrow, oblong, articular depression on the lateral side of the coronoid process; it receives the circumferential articular surface of the head of the radius also known as the radial notch.
olecranon process
the large process of the ulna that projects behind the elbow, forms the bony prominence of the elbow, and receives the insertion of the triceps muscle
coronoid process
a projection from the front of the ulna forming part of the articulation of the elbow
ulnar tuberosity
a prominence at the lower border of the anterior surface of the coronoid process, giving attachment (insertion) to the brachialis muscle
radial notch
a narrow depression on the lateral side of the coronoid process of the ulna that articulates with the head of the radius and gives attachment to the annular ligament of the radius
interosseous (border) crest
begins above by the union of two lines, which converge from the extremities of the radial notch and enclose between them a triangular space for the origin of part of the Supinator; it ends below at the head of the ulna
ulna head
see picture
styloid process
found at distal end of the forearm, and projects from the medial and back part of the bone; it descends a little lower than the head, and its rounded end affords attachment to the ulnar collateral ligament of the wrist
