thoracic spine

spine (spīn)

1. a slender, thornlike process or projection.

2. vertebral column.

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alar spine , angular spine s. of sphenoid bone.

bamboo spine  the rigid spine produced by ankylosing spondylitis, so called from its radiographic appearance.

cervical spine  that portion of the spine comprising the cervical vertebrae.

cleft spine  spina bifida.

ischial spine  a bony process projecting backward and medialward from the posterior border of the ischium.

lumbar spine  that portion of the spine comprising the lumbar vertebrae.

mental spine, inferior  the lower part of a small bony projection on the internal surface of the mandible, near the lower end of the midline, serving for attachment of the geniohyoid muscle.

mental spine, superior  the upper part of a small bony projection on the internal surface of the mandible, near the lower end of the midline, serving for attachment of the genioglossus muscle.

nasal spine, anterior  the sharp anterosuperior projection at the anterior extremity of the nasal crest of the maxilla.

nasal spine, posterior  a sharp, backward-projecting bony spine forming the medial posterior angle of the horizontal part of the palatine bone.

neural spine  the spinous process of a vertebra.

palatine spines  laterally placed ridges on the lower surface of the maxillary part of the hard palate, separating the palatine sulci.

poker spine , rigid spine the ankylosed spine produced by rheumatoid spondylitis.

spine of scapula  a triangular bony plate attached by one end to the back of the scapula.

sciatic spine  ischial s.

spine of sphenoid bone  the posterior and downward projection from the lower aspect of the great wing of the sphenoid bone.

thoracic spine  that part of the spine comprising the thoracic vertebrae.

spine of tibia  a longitudinally elongated, raised and roughened area on the anterior crest of the tibia.

trochlear spine  a bony spicule on the anteromedial part of the orbital surface of the frontal bone for attachment of the trochlea of the superior oblique muscle.

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thoracic spine,

that part of the spine comprising the thoracic vertebrae.

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spine [spīn]

1. a thornlike process or projection; called also acantha and spina.

2. the rigid bony structure in the midline of the back, composed of the vertebrae; called also backbone, spinal column, and vertebral column.



The spinal column is the axis of the skeleton; the skull and limbs are in a sense appendages. The vertebrae also provide the protective bony corridor (spinal canal) through which the spinal cord passes; they can move to a certain extent and so give flexibility to the spine, allowing it to bend forward, sideways and, to a lesser extent, backward. In the areas of the neck and lower back, the spine also can pivot, which permits the turning of the head and torso.

There are usually 24 movable vertebrae and nine that are fused together. The topmost are the seven cervical vertebrae, which form the back of the neck, supporting the skull. The head turns from side to side by means of a pivotal motion between the two highest vertebrae. Below these are the 12 thoracic vertebrae, the supports on which the ribs are hinged, and then the five lumbar vertebrae, the largest movable vertebrae (the cervical are the smallest). Below the lumbar vertebrae, the spine terminates with two groups of vertebrae fused into single bones: the sacrum, composed of five vertebrae, and the coccyx, composed of four vertebrae. Viewed from the side of the body, the spine has the shape of a gentle double S curve.

Malformations of the Spine. Of the various types of spinal malformations, some are congenital and others the result of postural defects or injuries. spina bifida is congenital. kyphosis may occasionally be congenital but is more often caused by one of the diseases that attack the structure of the bones. The most common of these is pott's disease, or tuberculosis affecting the vertebrae and soft tissues of the spine. Another is osteitis deformans, a type of bone inflammation in which parts of the bone are replaced by softer tissue. scoliosis is a curvature of the spine toward one side.

cervical spine that portion of the spine comprising the cervical vertebrae.

lumbar spine that portion of the spine comprising the lumbar vertebrae.

thoracic spine that part of the spine comprising the thoracic vertebrae.