posterior intercostals
No one bone protects the spinal cord. The spine consists of 33 bones called vertebrae, of which the spinal cord travels through the center. These vertebrae are held in place, or supported, by ligaments and muscles. Cushions between each vertebrae are called discs. So, essentially, the spinal cord is protected by bone, discs, ligaments and the muscles.
The diaphragm is stimulated the same way all other muscles are - nerve impulses that originate in the brain (or sometimes the spinal cord). The intercostal muscles expand during inhalation and contract during exhalation in response to the movement of the lungs by the diaphragm.
The abdominal muscles are primarily innervated by the lower intercostal nerves, which originate from the thoracic spinal nerves. These nerves come together to form the lower thoracic intercostal nerves and the subcostal nerve, collectively contributing to the innervation of the abdominal muscles.
The vertebral artery passes through the transverse foramina of the cervical vertebrae. These arteries supply blood to the brain and spinal cord.
Intercostal muscles are several groups of muscles that run between the ribs, and help form and move the chest wall. There are three principal layers; * the external intercostal muscles, which aid in quiet and forced inhalation. They originate on ribs 1-11 and have their insertion on ribs 2-12. The external intercostals are responsible for the elevation of the ribs, and expanding the transverse dimensions of the thoracic cavity. Located around the the ribs * the internal intercostal muscles, which aid in forced expiration (quiet expiration is a passive process). They originate on ribs 1-11 and have their insertions on ribs 2-12. The internal intercostals are responsible for the depression of the ribs decreasing the transverse dimensions of the thoracic cavity. * the innermost intercostal muscle Both the external and internal muscles are innervated by the intercostal nerves (the ventral rami of thoracic spinal nerves), and are provided by the intercostal arteries and intercostal veins. Their fibers run in opposite directions.
The spinal processes of the upper thoracic vertebrae are the origin of the rhomboid muscles, specifically the rhomboid major and rhomboid minor. These muscles play a role in scapular retraction and provide stability to the shoulder blade region.
The ventral rami serves as a form of intercostal nerves, which supply the muscles between the ribs and the skin and muscles of the anterior and lateral trunk.
The spinal cord
That is a good question. You have twelve intercostal nerves going between your ribs. They supply the intercostal muscles and carry back the sensations. You have the brachial plexus and lumbosacral plexuses. They are complicated as on today. But long back in evolution scale they were parallel. There complicated arrangement tells the the movement of muscle mass during evolution.
Anterior branches of thoracic spinal nerves.
in the spinal canal between the vertebrae.
second lumber vertebrae