HOME





Levator Scapulae
The levator scapulae is a slender skeletal muscle situated at the back and side of the neck. It originates from the transverse processes of the four uppermost cervical vertebrae; it inserts onto the upper portion of the medial border of the scapula. It is innervated by the cervical nerves C3-C4, and frequently also by the dorsal scapular nerve. As the Latin name suggests, its main function is to lift the scapula. Anatomy Attachments The muscle descends diagonally from its origin to its insertion. Origin The levator scapulae originates from the posterior tubercles of the transverse processes of cervical vertebrae C1-4. At its origin, it attaches via tendinous slips. Insertion It inserts onto the medial border of the scapula (with its site of insertion extending between the superior angle of the scapula superiorly, and the junction of spine of scapula and medial border of scapula inferiorly). Relations One of the muscles within the floor of the posterior triangle of th ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Vertebral Column
The spinal column, also known as the vertebral column, spine or backbone, is the core part of the axial skeleton in vertebrates. The vertebral column is the defining and eponymous characteristic of the vertebrate. The spinal column is a segmented column of vertebrae that surrounds and protects the spinal cord. The vertebrae are separated by intervertebral discs in a series of cartilaginous joints. The dorsal portion of the spinal column houses the spinal canal, an elongated body cavity, cavity formed by the alignment of the vertebral neural arches that encloses and protects the spinal cord, with spinal nerves exiting via the intervertebral foramina to innervate each body segment. There are around 50,000 species of animals that have a vertebral column. The human spine is one of the most-studied examples, as the general structure of human vertebrae is fairly homology (biology), typical of that found in other mammals, reptiles, and birds. The shape of the vertebral body does, howev ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Posterior Triangle Of The Neck
The posterior triangle (or lateral cervical region) is a region of the neck. Boundaries The posterior triangle has the following boundaries: Apex: Union of the sternocleidomastoid and the trapezius muscles at the superior nuchal line of the occipital bone Anteriorly: Posterior border of the sternocleidomastoideus Posteriorly: Anterior border of the trapezius Inferiorly: Middle one third of the clavicle Roof: Investing layer of the deep cervical fascia Floor: (From superior to inferior) 1) M. semispinalis capitis 2) M. splenius capitis 3) M. levator scapulae 4) M. scalenus posterior 5) M. scalenus medius Divisions The posterior triangle is crossed, about 2.5 cm above the clavicle, by the inferior belly of the omohyoid muscle, which divides the space into two triangles: * an upper or occipital triangle * a lower or subclavian triangle (or supraclavicular triangle) Contents A) Nerves and plexuses: * Spinal accessory nerve (Cranial Nerve XI) * Branches of cervic ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cervical Nerves
A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the corresponding cervical, thoracic, lumbar, sacral and coccygeal regions of the spine. There are eight pairs of cervical nerves, twelve pairs of thoracic nerves, five pairs of lumbar nerves, five pairs of sacral nerves, and one pair of coccygeal nerves. The spinal nerves are part of the peripheral nervous system. Structure Each spinal nerve is a mixed nerve, formed from the combination of nerve root fibers from its dorsal and ventral roots. The dorsal root is the afferent sensory root and carries sensory information to the brain. The ventral root is the efferent motor root and carries motor information from the brain. The spinal nerve emerges from the spinal column through an opening ( intervertebral foramen) between adjace ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Gray's Anatomy
''Gray's Anatomy'' is a reference book of human anatomy written by Henry Gray, illustrated by Henry Vandyke Carter and first published in London in 1858. It has had multiple revised editions, and the current edition, the 42nd (October 2020), remains a standard reference, often considered "the doctors' bible". Earlier editions were called ''Anatomy: Descriptive and Surgical'', ''Anatomy of the Human Body'' and ''Gray's Anatomy: Descriptive and Applied'', but the book's name is commonly shortened to, and later editions are titled, ''Gray's Anatomy''. The book is widely regarded as an extremely influential work on the subject. Publication history Origins The English anatomist Henry Gray was born in 1827. He studied the development of the endocrine glands and spleen and in 1853 was appointed Lecturer on Anatomy at St George's Hospital Medical School in London. In 1855, he approached his colleague Henry Vandyke Carter with his idea to produce an inexpensive and access ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Clavicle
The clavicle, collarbone, or keybone is a slender, S-shaped long bone approximately long that serves as a strut between the scapula, shoulder blade and the sternum (breastbone). There are two clavicles, one on each side of the body. The clavicle is the only long bone in the body that lies horizontally. Together with the shoulder blade, it makes up the shoulder girdle. It is a palpable bone and, in people who have less fat in this region, the location of the bone is clearly visible. It receives its name from Latin ''clavicula'' 'little key' because the bone rotates along its axis like a key when the shoulder is Abduction (kinesiology), abducted. The clavicle is the most commonly fractured bone. It can easily be fractured by impacts to the shoulder from the force of falling on outstretched arms or by a direct hit. Structure The collarbone is a thin doubly curved long bone that connects the human arm, arm to the torso, trunk of the body. Located directly above the first rib, it ac ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Serratus Anterior
The serratus anterior is a muscle of the chest. It originates at the side of the chest from the upper 8 or 9 ribs; it inserts along the entire length of the anterior aspect of the medial border of the scapula. It is innervated by the long thoracic nerve from the brachial plexus. The serratus anterior acts to pull the scapula forward around the thorax. The muscle is named from Latin: ''serrare'' = to saw (referring to the shape); and ''anterior'' = on the front side of the body. Structure Origin Serratus anterior normally originates by nine or ten muscle slips – arising from either the 1st to 8th ribs, or the 1st to 9th ribs; because two slips usually arise from the 2nd rib, the number of slips is greater than the number of ribs from which they originate. Insertion The muscle is inserted along the medial border of the scapula between the superior and inferior angle of the scapula. The muscle is divided into three parts according to the points of insertion: * the se ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Scalene Muscles
The scalene muscles are a group of three muscles on each side of the neck, identified as the anterior, the middle, and the posterior. They are innervated by the third to the eighth cervical spinal nerves (C3-C8). The anterior and middle scalene muscles lift the first rib and bend the neck to the side they are on. The posterior scalene lifts the second rib and tilts the neck to the same side. The muscles are named from the Ancient Greek (), meaning 'uneven'. Structure The scalene muscles are attached at one end to bony protrusions on vertebrae C2 to C7 and at the other end to the first and second ribs. Anterior scalene The anterior scalene muscle (), lies deeply at the side of the neck, behind the sternocleidomastoid muscle. It arises from the anterior tubercles of the transverse processes of the third, fourth, fifth, and sixth cervical vertebrae, and descending, almost vertically, is inserted by a narrow, flat tendon into the scalene tubercle on the inner border of the ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Mastoid Part Of The Temporal Bone
The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, the mastoid part articulates with two other bones. Etymology The word "mastoid" is derived from the Greek word for "breast", a reference to the shape of this bone. Surfaces Outer surface Its outer surface is rough and gives attachment to the occipitalis and posterior auricular muscles. It is perforated by numerous foramina (holes); for example, the mastoid foramen is situated near the posterior border and transmits a vein to the transverse sinus and a small branch of the occipital artery to the dura mater. The position and size of this foramen are very variable; it is not always present; sometimes it is situated in the occipital bone, or in the suture between the temporal and the occipital. Mastoid process The mastoid process is ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Trapezius
The trapezius is a large paired trapezoid-shaped surface muscle that extends longitudinally from the occipital bone to the lower thoracic vertebrae of the human spine, spine and laterally to the spine of the scapula. It moves the scapula and supports the arm. The trapezius has three functional parts: * an upper (descending) part which supports the weight of the arm; * a middle region (transverse), which retracts the scapula; and * a lower (ascending) part which medially rotates and depresses the scapula. Name and history The trapezius muscle resembles a trapezoid, trapezium, also known as a trapezoid, or diamond-shaped quadrilateral. The word "spinotrapezius" refers to the human trapezius, although it is not commonly used in modern texts. In other mammals, it refers to a portion of the analogous muscle. Structure The ''superior'' or ''upper'' (or descending) fibers of the trapezius originate from the spinous process of C7, the external occipital protuberance, the me ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Splenius Capitis
The splenius capitis () () is a broad, straplike muscle in the back of the neck. It pulls on the base of the skull from the vertebrae cervical vertebra, in the neck and upper Thoracic vertebrae, thorax. It is involved in movements such as shaking the head. Structure It arises from the lower half of the nuchal ligament, from the spinous process of the Vertebra prominens, seventh cervical vertebra, and from the spinous processes of the upper three or four thoracic vertebrae. The fibers of the muscle are directed upward and laterally and are inserted, under cover of the sternocleidomastoideus, into the mastoid process of the temporal bone, and into the rough surface on the occipital bone just below the lateral third of the superior nuchal line. The splenius capitis is deep to sternocleidomastoideus at the mastoid process, and to the trapezius for its lower portion. It is one of the muscles that forms the floor of the posterior triangle of the neck. The splenius capitis muscle is in ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Sternocleidomastoid Muscle
The sternocleidomastoid muscle is one of the largest and most superficial cervical muscles. The primary actions of the muscle are rotation of the head to the opposite side and Anatomical terms of motion#Flexion and extension, flexion of the neck. The sternocleidomastoid is innervated by the accessory nerve. Etymology and location It is given the name ''sternocleidomastoid'' because it originates at the manubrium of the Human sternum, sternum (''sterno-'') and the clavicle (''cleido-'') and has an Insertion (anatomy), insertion at the mastoid process of the temporal bone of the human skull, skull. Structure The sternocleidomastoid muscle originates from two locations: the manubrium of the Human sternum, sternum and the clavicle, hence it is said to have two heads: sternal head and clavicular head. It travels obliquely across the side of the neck and inserts at the mastoid process of the temporal bone of the human skull, skull by a thin aponeurosis. The sternocleidomastoid is thick ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Spinal Accessory Nerve
The accessory nerve, also known as the eleventh cranial nerve, cranial nerve XI, or simply CN XI, is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. It is classified as the eleventh of twelve pairs of cranial nerves because part of it was formerly believed to originate in the brain. The sternocleidomastoid muscle tilts and rotates the head, whereas the trapezius muscle, connecting to the scapula, acts to shrug the shoulder. Traditional descriptions of the accessory nerve divide it into a spinal part and a cranial part. The cranial component rapidly joins the vagus nerve, and there is ongoing debate about whether the cranial part should be considered part of the accessory nerve proper. Consequently, the term "accessory nerve" usually refers only to nerve supplying the sternocleidomastoid and trapezius muscles, also called the spinal accessory nerve. Strength testing of these muscles can be measured during a neurological examination to assess functio ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]