Bones of upper limb
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Bones of upper limb
description
Bones of upper limb. Clavicle. GENERAL FEATURES The clavicle is the first bone to begin ossification, which occurs during the 6 th week intrauterine life. It ossifies from membrane (membranous ossification). THE CLAVICLE HAS TWO ENDS, TWO SURFACES AND TWO CURVES . . - PowerPoint PPT Presentation
Transcript of Bones of upper limb
Bones of upper limb
Clavicle
•GENERAL FEATURES
•The clavicle is the first bone to begin ossification, which occurs during the 6th week intrauterine life. It ossifies from membrane (membranous ossification). •THE CLAVICLE HAS TWO ENDS, TWO SURFACES AND TWO CURVES.
•The medial two thirds of the clavicle are curved forwards, while the lateral third is curved backwards. Its lateral third is flattened from above downward, while its medial two-thirds are rounded.
•How can you identify the side, whether right or left?• Put the rounded end medially. Put the smooth surface upwards. Put the large curve medially with forward
convexity.
•It is most often fractured in the middle third of its length which is its weakest point. The lateral fragment is depressed by the weight of the arm and is pulled medially and forward by the strong adductor muscles of the shoulder joint, especially the pectoralis major. The medial segment is pulled upwards by the sternomastoid muscle.
Scapula
•GENERAL FEATURES
•The scapula is triangular in shape, thus it has three borders and three angles. It also has three processes and three fossae.
How can you identify the side, whether right or left? Put the spine posteriorly. Put the acute angle inferiorly. Put the glenoid cavity laterally.
Scapula
Humerus
It has an upper end, shaft, and lower end.
How can you identify the side, whether right or left?
Put the head above and medially.Put the bicipital groove anteriorly.
Humerus
Anterior view Posterior view
Nerves Related to the Humerus:The following nerves are intimately related to the humerus:
1.Radial nerve: passes in the spiral groove. Thus it can be injured in fractured shaft of the humerus.
2.Axillary nerve: passes around the surgical neck of the humerus.
3.Ulnar nerve: passes behind the medial epicondyle.
THE ULNA
It is a long bone, placed at the medial side of the forearm, parallel with the radius.It is divisible into a body and two ends .
The Radius
It is situated on the lateral side of the ulna.Its upper end is small, disc like and forms only a small part of the elbow-joint; but its lower end is large, and forms the chief part of the wrist-joint. It has a shaft and two ends.
�ٌRadius& Ulna
Hand bones
THANK YOUProf. Dr. Maha Safwat
