M2B-Humerus and Clavicle

Humerus

Consists of one long bone and it has two articulations

Humeral Condyle

Entire articular surface of the distal humerus that articulates with the bones of the forearm to form the elbow joint. There are 2 parts of the condyle, capitulum and trochlea

Capitulum

Rounded surface on the lateral side of the condyle, shaped like a half-sphere, articulates with the radial head

Trochlea

Located on the medial side of the condyle, it is shaped like a pulley, has two distinct edges and articulates with the ulna

Lateral Epicondyle

Lateral edge of the distal humerus, lateral and superior to the capitulum, proximal to elbow joint

Medial Epicondyle

Located on the medial edge of the distal humerus, can be easily palpated, proximal to elbow joint

Supracondylar Ridges

Sharp bony edges that are located above both epicondyles. These ridges extend up the shaft of the distal humerus, giving it the shape of wide and flat

Humeral Head

Smooth, rounded surface that is covered by hyaline cartilage.  It is directed superior, medial and posterior in relation to the rest of the humerus

Greater Tuberosity (Tubercle)

Situated on the postero-lateral side of the humerus and is best seen in profile radiographically in true anatomical position, site for the attachment of the supraspinatous, infraspinatous and teres minor muscles

Lesser Tuberosity (Tubercle)

Situated in the mid-anterior aspect of the humerus and serves as a site for the attachment of the subscapularis muscle

Bicipital Groove

Channel located between the lesser and greater tuberosities. It is a passageway for the biceps tendon

Clavicle

Connects the arm and shoulder girdle to the axial skeleton. It is the first bone to ossify in utero

Medial End of Clavicle

Also referred to as the sternal end as it articulates with the sternum at the lateral aspect of the manubrium to form the SC Joint, This is the only true articulation that the upper limb has with the torso

Lateral End of Clavicle

Also referred to as the acromial end as it articulates with the medial side of the acromion to form the AC Joint

Shaft of Clavicle

Consists of a double curve in the ant-post direction. The medial 2/3^rd is convex (towards anterior) while the lateral 1/3^rd is concave (from anterior)

Conoid Tubercle

Small bony prominence on the inferior surface on the lateral end of the clavicle. It is the attachment site for the conoid ligament