Anatomy L13 - Embryo L05 - Development of Skeletal System Flashcards
How many cervical somites are there compared to cervical vertebrae?
8 cervical somites fuse to form 7 cervical vertebrae. The caudal aspect of the superior somite fuses with the rostral aspect of the inferior somite to form the vertebral body.
How are cervical spinal nerves named in relation to their vertebrae?
Cervical spinal nerves exit ABOVE their corresponding vertebra of the same number
What is the centrum?
The centrum is another term for the vertebral body.
What is the nucleus pulposus?
The nucleu pulposus is a remnant of the notochord formed when the notochord regresses everywhere except where it is incorporated into the intervertebral discs
What is congenital scoliosis?
Congenital scoliosis is the abnormal lateral curvature of the spine resulting from disruption of normal vertebral development. All defects in congenital scoliosis are the results of of abnormal formation and segmentation of the vertebral precursors.
What is the pathology of wedge formation leading to congenital scoliosis?
Failure of formation of vertebra
How do ribs form?
Ribs arise from zones of condensed mesenchyme lateral to the body of the vertebra (i.e the sclerotome). Ribs develop from costal processes only in the thoracic region.
How does the sternum form?
The sternum develops from cartilaginous sternal bars in the ventral body wall. These bars fuse with one another in the cranial/caudal direction.
What is the sternum?
The sternum is a osteologic structure comprising the manubrium, body, and xyphoid process that forms from cartilaginous sternal bars fusing to one another in the cranial/caudal direction in the ventral body wall.
What is pectus carinatum?
Pectus carinatum is an overgrowth of cartilage causing the sternum to protrude. It may occur as a solitary congenital abnormality or in association with other genetic disorders or syndromes. Often seen in adolescent males experiencing a growth spurt.
What is pectus excavatum?
Pectus excavatum is assumed to be caused by overgrowth of the costal cartilage. This overgrowth of costal cartilage restricts the expansion of the ribs and pushes the sternum inward. At present, the definite cause is unknown.
What is a sternal foramen?
A sternal foramen is an ossification anomaly found in 4-10% of the population. It is a hole (foramen) in any part of the sternum (usually the body) that can be mistaken for a bullet wound or sternal disease. This is a common acupuncture site that sits directly over the heart.
