The thoracic vertebra is characterized by multiple-choice questions.

The characteristics of thoracic vertebrae are as follows:

The thoracic vertebra, located in the chest, is an important part of human skeleton, which is of great significance to people's overall action ability and coordination ability. Of course, the thoracic vertebra is also composed of different parts. Different types of thoracic vertebrae play different roles and affect other nerves.

I. Concept

1. Human thoracic vertebrae 12.

2. The vertebral body gradually increases from top to bottom, and the cross section is heart-shaped. The upper and lower edges on both sides are respectively provided with upper and lower rib recesses related to the rib heads. There is a recess of transverse process related to costal tubercle in front of the end of transverse process.

3. The costal fossa of each thoracic vertebra below the first thoracic vertebra and the ninth thoracic vertebra is atypical.

4. The articular surface of the articular process is almost coronal, with the articular surface of the upper articular process facing backward and the articular surface of the lower articular process facing forward.

5. The spinous process is long and inclined backward and downward, and the adjacent spinous processes are arranged in imbricate shape.

Second, thoracic vertebra anatomy

1, spine

The thoracic vertebra (T) has 12 vertebrae, T 1- 12 is from top to bottom, and 1 thoracic vertebra is sometimes called the eighth cervical vertebra, which is obviously different from cervical vertebra and lumbar vertebra. It has ribs to help maintain stability. In fact, the thoracic segment of the spine is a barrel structure composed of thoracic vertebrae, ribs and sternum. Compared with cervical vertebrae and lumbar vertebrae, it is less likely to be dislocated because of its good stability.

Typical thoracic vertebrae include vertebral body, vertebral arch and protuberance, and the vertebrae gradually increase from top to bottom (that is, from chest 1 to chest 12). There is spinous process behind the vertebral body, transverse process on the side and one articular process on the left and right. There is a hemispherical rib pit at the back of the vertebral body near the upper and lower edges of the body, which forms an intercostal transverse seam with the ribs.

The articular surfaces of the superior articular process and the inferior articular process are almost coronal; The spinous process is long, extending backward and covering each other in turn, showing imbricate shape. These are different anatomical features of cervical and lumbar vertebrae.

2. Thoracospinal nerve

The thoracic spinal nerve and thoracic nerve from the thoracic segment of the spinal cord are 12 pairs, which pass through the lower edge of the thoracic vertebra in the same order, and both have anterior and posterior branches. Except 1 thoracic nerve participates in brachial plexus, the anterior branch is not a plexus, which is called intercostal nerve and runs in intercostal sulcus. The posterior branch enters the back backward and is divided into medial branch and lateral branch, which dominate the back.

3. Sympathetic nerve

Thoracic sympathetic nerve and spinal nerve go hand in hand, which can be called visceral nerve, regulating and directing visceral activities. Among them, cardiothoracic nerve, splanchnic nerve, splanchnic nerve and visceral nerve are in charge of the functions of heart, stomach, liver, gallbladder, pancreas, small intestine and kidney respectively. Therefore, dislocation of thoracic vertebrae is closely related to the whole visceral function and general health.

Third, the relationship with organs.

Upper segment: The thoracic nerve belongs to the "cardiothoracic nerve".