Spinous process (plural spinous processes) (anatomy) A bony process of a vertebra that projects posteriorly from the neural arch and serves as attachment for muscles and ligaments. Also, why are the spinous processes of cervical vertebrae bifid? The spinous process of a typical cervical vertebra is short and bifid posteriorly. This is an opening in the ‘transverse process’ that allows passage of a small artery called the ‘vertebral artery’. ‘Bifid’ means that the spinous process is divided into two ‘clefts’. The spinous process protrudes where the laminae of the vertebral arch join and provides the point of attachment for muscles and ligaments of the spine. Spinous process is a bony projection off the posterior (back) of each vertebra.
These grooves are formed by laminae in the cervical and lumbar regions. Lateral to the spinous processes are the vertebral grooves. Some muscles attaching to the spinous processes also rotate the vertebrae to which they attach.
Most of the muscles that attach to the spinous processes act to extend the vertebral column. There are seven processes projecting from the vertebra: These processes provide sites to which back muscles and ligaments attach. The two transverse processes are located on either side of the ring, while the spinous process is located in the middle. On each vertebra, there are two transverse processes and one spinous process. Two regions of the spinal cord are enlarged to accommodate the greater number of nerve cells and connections needed to process information related to the upper and lower limbs (see Figure 1.10B). Why is spinal cord thicker in cervical and lumbar regions? The inferior and superior articular processes arise at the junction of the transverse process and the laminae. What is the first vertebra with bifid spinous process?Ĭervical Vertebrae (C2-C7) Each vertebra has two laminae posteriorly that fuse to form small bifid spinous processes, with the exception of C7, which has a long prominent spinous process. The spinous processes of the C3–C6 vertebrae are short, but the spine of C7 is much longer. Which spinous processes are bifid?Ĭervical vertebrae usually have a bifid (Y-shaped) spinous process. The spinous process is short and bifid (to allow ligamentum nuchae to run through). What is the function of the bifid spinous process?īony Structures The laminae are long, narrow, and thinner above than below.
At each of these levels, whites showed a higher frequency of bifidity than blacks and males a higher frequency of bifidity than females. Significant differences between race/sex subgroups were found at C3-C6. At C7, nearly all (98%) had nonbifid spinous processes. At C2, most individuals (91%) had bifid spinous processes. Data were analyzed using Chi-square and logistic regression analysis. Sex and race were kept entirely unknown to the classifier (S.M.D.) during data collection. Spinous processes were classified as "bifid," "partially bifid," or "nonbifid" based on previously defined criteria. The sample was selected from the Hamann-Todd collection, a large modern anatomical collection of known sex and race. In this study, the frequency of bifidity of cervical spinous processes at different vertebral levels was examined in a sample of 359 Americans of African (black) and European (white) descent. Few reliable postcranial indicators are known. Race is most commonly assessed using cranial traits. Determination of race (ancestry) is an important step in the identification of individuals in forensic cases.
0 kommentar(er)
