The Ischium (the upper part of the spine) is a series of bones which connect the skull to the back. The most prominent feature are four pairs of ribs: two large ones at either side and one pair just above the shoulders. These are known collectively as the thoracic vertebrae or simply as vertebral bodies. There are also three pairs of abdominal ribs, but these do not have any bearing on your posture, so they’re not discussed here.
The lower part of the spine consists of five pairs of ribs, called the lumbar vertebrae. They lie between the thoracic vertebrae and the sacrum. Lumbar vertebrae are very flexible and can move around inside their sockets, which makes them ideal for bending over when sitting down. However, they cannot support much weight; if you try to bend over with too much force in one place it will cause damage to other parts of your body.
In addition to the vertebral bodies, there are several ligaments and tendons running through the spinal column. Most of these attach to the vertebral bodies, but some run along them instead. When you stretch out your neck, for example, you may feel a pull on one of these muscles. If it’s tight then it means that there is something blocking its movement from where it attaches to the vertebral body.
The spinal cord is the part of the nervous system that carries messages to and from your brain. It consists of a bundle of nerve cells, surrounded by protective layers of tissue. Nerves emerge from the spinal cord in long cables, called peripheral nerves, which carry messages to the rest of the body. These are classified according to which region of the body they affect.
Nerves that affect the trunk, or main mass of the body, are called somatic nerves . There are three of these: the lowest part of the spinal cord (the bulbous end, or conus medularis) is separated from the upper part (the trunk, or spinal canal) by a piece of connective tissue called the dura mater. The nerves emerging from this are known as the cauda equina .
Sources & references used in this article:
Avulsion fracture of the ischial tuberosity in adolescents—an easily missed diagnosis by S Gidwani, J Jagiello, M Bircher – Bmj, 2004 – bmj.com
Osteotomy of the ischial tuberosity to provide surgical access to the ischium and caudal acetabulum in the dog. by JA Chalman, CE Layton – Journal of the American Animal Hospital …, 1990 – cabdirect.org
Sensitivity for pressure difference on the ischial tuberosity by RHM Goossens, R Teeuw, CJ Snijders – Ergonomics, 2005 – Taylor & Francis
CO2 Laser Debridement and Negative Pressure Wound Therapy With Endoscopic Support for Treatment of Sinus Wound at the Ischial Tuberosity: Case Report by JJ Tang, G Tao, Y Liu, X Ma… – … Journal of Lower …, 2020 – journals.sagepub.com
Force on the sacrococcygeal and ischial areas during posterior pelvic tilt in seated posture by T Kemmoku, K Furumachi… – Prosthetics and …, 2013 – journals.sagepub.com
Proximal hamstring strains of stretching type in different sports: injury situations, clinical and magnetic resonance imaging characteristics, and return to sport by CM Askling, M Tengvar, T Saartok… – … American journal of …, 2008 – journals.sagepub.com
Acute first-time hamstring strains during high-speed running: a longitudinal study including clinical and magnetic resonance imaging findings by CM Askling, M Tengvar, T Saartok… – … American journal of …, 2007 – journals.sagepub.com
What role for MRI in hamstring strains? An argument for a difference between recreational and professional athletes by J Orchard – 2014 – bjsm.bmj.com