This article uses some professional terms to describe relative positions and directions. See Anatomical terms of location for more detailed information. In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species

Bone: Clavicle
Gray's	subject #49 200
MeSH	Clavicle

In human anatomy, the clavicle or collar bone is classified as a long bone that makes up part of the shoulder girdle (pectoral girdle). Introduction ( classes Long bones body or Diaphysis Medullary canal Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus Anatomy (from the Greek anatomia, from ana separate apart from and temnein, to cut up cut open is a branch of Biology that is the consideration Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce In Human anatomy, the shoulder joint comprises the part of the body where the Humerus attaches to the Scapula. This article is about the item of clothing In the Scots language, girdle refers to a cooking griddle. The pectoral girdle is the set of bones which connect the upper limb to the axial skeleton on each side It receives its name from the Latin clavicula ("little key") because the bone rotates along its axis like a key when the shoulder is abducted. Abduction, in functional anatomy is a movement which draws a limb away from the median ( Sagittal) plane of the body (This movement is palpable with the opposite hand). In some people, particularly females who may have less fat in this region, the location of the bone is clearly visible as it creates a bulge in the skin.

Overview

Right clavicle - from below, and from above.

Left clavicle - from above, and from below.

The clavicle is a doubly curved short bone that connects the arm (upper limb) to the body (trunk), located directly above the first rib. In Human anatomy, the upper limb (also upper extremity) refers to what in common English is known as the arm, that is the region of the shoulder It acts as a shunt to keep the scapula in position so the arm can hang freely. Medially, it articulates with the manubrium of the sternum (breast-bone) at the sternoclavicular joint. The sternum (from Greek στέρνον sternon, "chest" or breastbone) is a long flat Bone located in the center of the thorax (chest The sternoclavicular articulation is a double arthrodial Joint composed of two portions separated by an Articular disc. At its lateral end it articulates with the acromion of the scapula (shoulder blade) at the acromioclavicular joint. The acromion process, or simply the acromion (from Greek akros, "highest" ōmos, "shoulder" is an anatomical feature In Anatomy, the scapula, omo, or shoulder blade, is the Bone that connects the Humerus (arm bone with the Clavicle (collar The acromioclavicular joint, or AC joint, is a Joint at the top of the Shoulder. It has a rounded medial end and a flattened lateral end.

From the roughly pyramidal sternal end, each clavicle curves laterally and posteriorly for roughly half its length. It then forms a smooth posterior curve to articulate with a process of the scapula (acromion). The acromion process, or simply the acromion (from Greek akros, "highest" ōmos, "shoulder" is an anatomical feature The flat, acromial end of the clavicle is broader than the sternal end. The acromial end has a rough inferior surface that bears prominent lines and tubercles. These surface features are attachment sites for muscles and ligaments of the shoulder.

Functions

The clavicle serves several functions:

• It serves as a rigid support from which the scapula and free limb are suspended. This arrangement keeps the upper limb (arm) away from the thorax so that the arm has maximum range of movement.
• Covers the cervicoaxillary canal (passageway between the neck and arm), through which several important structures pass.
• Transmits physical impacts from the upper limb to the axial skeleton. The axial skeleton consists of the 80 bones in the head and trunk of the human body

Even though it is classified as a long bone, the clavicle has no medullary (bone marrow) cavity like other long bones. The long bones are those that are longer than they are wide and grow primarily by elongation of the Diaphysis, with an Epiphysis at the ends of the growing Bone It is made up of spongy (cancellous) bone with a shell of compact bone. Cortical bone, or compact bone, is one of two main types of Osseous tissue. It is a dermal bone derived from elements originally attached to the skull. The dermal bone, the pattern and form of bones derived from Intramembranous ossification, define essential components of the Vertebrate skeleton including the skull

Attachments

Muscles and ligaments that attach to the clavicle include:

Development

The clavicle is the first bone to begin the process of ossification (laying down of minerals onto a preformed matrix) during development of the embryo, during the 5th and 6th weeks of gestation. In Human anatomy, the deltoid muscle is the Muscle forming the rounded contour of the Shoulder. In Human anatomy, the trapezius is a large Superficial Muscle which extends longitudinally from the occipital bone to the lower thoracic vertebrae The Subclavius is a small triangular muscle placed between the Clavicle and the First rib. On the medial part of the Clavicle is a broad rough surface the costal tuberosity (rhomboid impression rather more than 2 cm The Conoid Ligament, the posterior and medial fasciculus is a dense band of fibers conical in form with its base directed upward The Coracoclavicular Ligament serves to connect the Clavicle with the Coracoid process of the scapula At the posterior border of the Scapula, near the point where the prismatic joins with the flattened portion is a rough eminence the conoid tubercle (or coracoid tuberosity The trapezoid ligament, the anterior and lateral fasciculus is broad thin and quadrilateral it is placed obliquely between the coracoid process and the clavicle The Coracoclavicular Ligament serves to connect the Clavicle with the Coracoid process of the scapula From the Coracoid tuberosity an oblique ridge the trapezoid line (or trapezoid ridge, or oblique) runs forward and lateralward and affords attachment The Pectoralis major (popularly known as pecs) is a thick fan-shaped muscle situated at the upper front ( Anterior) of the Chest wall In Human Anatomy, the sternocleidomastoid (pronounced /ˌstɚ The sternohyoid muscle is a thin narrow muscle attaching the Hyoid bone to the Sternum, one of the paired Strap muscles of the Infrahyoid muscles In Human anatomy, the trapezius is a large Superficial Muscle which extends longitudinally from the occipital bone to the lower thoracic vertebrae Ossification is the process of Bone formation in which connective tissues such as Cartilage are turned to bone or bone-like tissue However, it is one of the last bones to finish ossification, at about 21-25 years of age. It forms by intramembranous ossification. Intramembranous ossification is one of the two processes during Fetal development of the mammalian skeletal system in which Bone tissue is created It consists of a mass of cancellous bone surrounded by a compact bone shell. Cancellous Bone is a type of Osseous tissue with a low density and strength but very high Surface area, that fills the inner cavity of long bones Cortical bone, or compact bone, is one of two main types of Osseous tissue. The cancellous bone forms via two ossification centres, one medial and one lateral, which fuse later on. The compact forms as the layer of fascia covering the bone stimulates the ossification of adjacent tissue. Fascia (făsh'ē-ə pl fas·ci·ae (făsh'ē-ē adj fascial (făsh'ē-əl (from Latin: a band is the Soft tissue component of The resulting compact bone is known as a periosteal collar.

Common clavicle injuries

• acromioclavicular dislocation
• sternoclavicular dislocations
• clavicle fractures
• osteolysis
• degeneration of the clavicle

Additional images

Pectoral girdle - front	Human arm bones diagram	Diagram of the human shoulder joint	Sternoclavicular articulation. A separated shoulder, otherwise known as an acromioclavicular separation or AC separation is a common injury to the Acromioclavicular joint. A clavicle fracture is a Bone fracture in the Clavicle, or collarbone. Osteolysis refers to an active resorption or dissolution of Bone tissue as part of an ongoing disease process Anterior view.
The left shoulder and acromioclavicular joints, and the proper ligaments of the scapula.	Muscles of the neck. Lateral view.	Muscles of the neck. Anterior view.	Anterolateral view of head and neck.
Front view of neck.

See also

• Clavicle fracture
• Bone terminology
• Terms for anatomical location
• The collarbones are sometimes partly or completely absent in cleidocranial dysostosis
• Wishbone or furcula - the fused clavicles of most birds

References

• Chung, Kyung. A clavicle fracture is a Bone fracture in the Clavicle, or collarbone. Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species Cleidocranial dysostosis, also called Cleidocranial dysplasia, is a Hereditary Congenital disorder due to Haploinsufficiency caused by mutations Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Board Review Series: Gross Anatomy, 4th edition.
• Moore, Keith L. and Arthur F. Dalley. Clinically Oriented Anatomy, 4th edition.
• Stedman's Medical Dictionary, 27th edition.
• Mosby's Medical, Nursing, and Allied Health Dictionary, 5th ed.

External links

• Illustration
• Fractures