Bones of the upper limb

3,605views

00:00 / 00:00

Notes

Bones of the Upper Limb

Figure 1. Anterior and B posterior view of scapula.
Figure 2. A Anterior view and B inferior view of clavicle.
Figure 3. A Anterior and B posterior view of humerus.
Figure 4. A Anterior view of ulna and radius and anterior view of the bones of the hand.
UNLABELLED DIAGRAMS

Transcript

Watch video only

The upper limb is connected to the axial skeleton, which is the cranium, vertebral column, and associated thoracic cage, by the bony pectoral girdle at the sternoclavicular joint, which is the connection between the clavicle and sternum.

Each upper limb is made up of 32 bones, and has a number of different regions.

First, there’s the pectoral girdle, which consists of 2 bones: the scapula, also called the shoulder blade, and the clavicle, also known as the collarbone.

Then there’s the arm, which only has one bone, called the humerus.

Then we have the forearm, which has two bones called the radius and the ulna.

Next, there’s the wrist, which has 8 carpal bones, and finally, the hand, which has 5 metacarpal bones, and the fingers, who have 14 phalanges in total.

OK, now let’s have a look at the shoulder girdle first.

The shoulder girdle consists of the scapula and clavicle, and articulates anteriorly with the manubrium of the sternum.

Starting with the scapula, it’s a flat triangular bone located on the posterior aspect of the shoulder, extending over the second to the seventh ribs.

The scapula helps to connect the rest of the upper limb to the trunk, while stabilizing and assisting the shoulder during movement while serving as an attachment point for numerous muscles and ligaments.

Now, like any respectable triangle, the scapula has three borders; the shortest and the thinnest of them is the superior border.

Then there’s the medial border, which runs parallel to the vertebral column, and finally, there’s the lateral border which is the thickest one.

The lateral border is also known as the axillary border because it points towards the axilla, or armpit region.

The point where the medial and lateral borders meet is the inferior angle, and we also have the superior angle which is the junction of the superior and medial borders.

At the lateral part of the superior border, there’s a small indentation called the scapular notch through which the suprascapular nerve passes.

Summary

The upper limb starts from the pectoral girdle to hand. The pectoral girdle is made up of the clavicle and scapula. Next is the arm, which contains the humerus, the forearm containing the radius and the ulna; the wrist made up of the carpals; the hand made up of the metacarpals; and finally, digits contain phalanges. Each bone has a unique shape that helps it perform its specific function.

Elsevier

Copyright © 2024 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Cookies are used by this site.

USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.

RELX