Human osteology : comprising a description of the bones ; with delineations of the attachments of the muscles, the general and microscopic structure of the bone and its development : to which is added a brief notice of the unity of type in the construction of the vertebrate skeleton / by Luther Holden.

  • Holden, Luther, 1815-1905.
Date:
1857
Catalogue details

Licence: Public Domain Mark

Credit: Human osteology : comprising a description of the bones ; with delineations of the attachments of the muscles, the general and microscopic structure of the bone and its development : to which is added a brief notice of the unity of type in the construction of the vertebrate skeleton / by Luther Holden. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    adaptation to the dorsal curve. They have two little cup-like articular surfaces on each side for the reception of the heads of the ribs, the lower cups being the larger. By referring to the spine (Plate II.), we observe that the socket for the head of the rib is formed by the articular cups of two vertebrae with the intervening fibro-cartilage. Their spinous processes are long and slanting, so that they overlap each other, and prevent extension of the spine in this region. Their transverse processes are thick and strong, and have each, near their ends, an articular surface for the ribs, which they support like so many buttresses. Observe that those of the eleventh and twelfth are very small, and have not this surface, because the corresponding ribs are too small and short to need their support. Of the articular processes, the upper look back- wards, the lower forwards, and the planes of both are so nearly vertical that it is manifest there can be but little movement between any two dorsal vertebra. The vertebral foramen is nearly roimd. Characters of With regard to the cervical vertebra3, their the Ckevical bodies present lateral ridges which fit into Vertebra. corresponding depressions on the side of the ver- tebra above, so as to prevent lateral displacement. They are smaller than in the dorsal region, and their greatest diameter is transverse. Their spinous processes are short and horizontal, m order to permit the free extension of the neck: observe more particularly the shortness of the third, fourth, and fifth. They are bifurcated* at the summit for muscular insertion. That of the seventh cervical vertebra is not bifurcated,—it projects beyond the others: and hence this vertebra is called the vertebra prominens. The reason of its greater projection is, to give additional leverage to the elastic ligament (Hgamentum nuchae), and the muscles which maintain the head erect. Their transverse processes are very remarkable. There is a large foramen through their base, for the passage of the vertebral artery: there is a groove on their upper surface for the lodgment of the spinal nerves; and this . This bifurcation of the spines of the cervical vertebra, is peculiar to the hunian skeJon the object being to afford n,ore room for the insertion of the powerful muscles which maintain the neck, and therefore the head, erect.