Humerus The humerus is the skeletal element of the brachium and it is the largest bone of the upper limb. It has a long cylindrical shaft that expands at the proximal and
distal ends. The proximal end is rounded, while the distal end is fl attened from anterior to posterior. The ends consist of a spongy core of bone covered with a thin lamina of compact bone. The shaft is a cylinder of thick compact bone surrounding a large medullary cavity. The humerus articulates with three bones — the scapula, ulna, and radius.
1 Head
2 Anatomical neck
3 Surgical neck
4 Greater tubercle
5 Lesser tubercle
6 Intertubercular sulcus or groove
7 Crest of greater tubercle
8 Crest of lesser tubercle
9 Shaft or body
10Groove for radial nerve
11Medial supracondylar ridge
12Deltoid tuberosity
13Capitulum
14Trochlea
15Olecranon fossa
16Coronoid fossa
17Radial fossa
18Medial epicondyle
19Groove for ulnar nerve
20Lateral epicondyle
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Left humerus |
Left humerus |
Anterior view, lateral to right |
Posterior view, lateral to left |
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Left humerus
Lateral view, anterior to left
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Left humerus
Superior view, lateral to left
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Ulna The ulna is the medial and longer bone of the antebrachium. It is thick and notched at its proximal end where it is a major contributor to the elbow joint. From the notched proximal end it tapers to a thin shaft that ends distally as a small rounded head. The ulna articulates with two
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Coronoid process |
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Radial notch |
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Trochlear notch |
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10Supinator crest
11Head
12Articular circumference
13Ulnar styloid process
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Left ulna |
Left ulna |
Anterior view, lateral to right |
Posterior view, lateral to left |
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Left ulna
Lateral view, anterior to left
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Left ulna
Superior view, lateral to left
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Left ulna
Inferior view, lateral to right
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Left ulna
Medial view, anterior to right
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