Detailed explanation of lumbar intervertebral disc

Lumbar spine (L) is located in the lower part of the spine, which has the functions of exercise, load bearing and protection. It is connected with thoracic vertebra and sacral vertebra, and its load and stability function is particularly important. The front part of lumbar vertebra is composed of vertebral body connected by intervertebral disc and longitudinal ligament; The posterior part consists of vertebral arch, lamina, transverse process and spinous process (Figure 1- 1-6). They are connected by joints, ligaments and muscles. Vertebral promontory L is enclosed between the anterior and posterior structures of lumbar vertebrae, and each vertebral body segment is connected into a spinal canal in turn to accommodate the lower end of spinal cord, conus and cauda equina nerve root. 2. Pedicle is the initial part of the vertebral arch, which is thick and emits vertically backward from the upper back of the lumbar body. The upper notch of the vertebral arch is shallower and narrower than the lower notch, and the upper and lower notches of adjacent vertebral segments form an ear-shaped intervertebral foramen. The vertebral arch extends backward to the lamina, superior and inferior articular processes, transverse processes and spinous processes.

Lumbar X-ray (B). Lateral X-ray film (a) shows: 1. Vertebral body; 2. Superior articular process; 3. Shimonoseki joint process; 4. pedicle; 5. spinous process; 6. transverse process 3. The lamina is a short, wide and thick plate-like structure formed by continuous posterior pedicle. Covered and connected by ligamentum flavum. The lumbar spine is tilted backward and downward. Normal blade thickness gradually becomes thinner from top to bottom.

4. Articular processes and articular processes The articular processes of lumbar vertebrae are obviously different from those of cervical vertebrae and thoracic vertebrae. The superior articular process originates from the posterior upper part of pedicle and inclines backward and outward. The inferior articular process emanates from the lower side of the lamina and protrudes forward. The upper and lower articular processes correspond to each other to form a articular process joint. The position and shape of facet joints in different segments of lumbar spine are not exactly the same. ~: The articular space of articular process is in the sagittal plane. The superior articular process forms a ring structure around the inferior articular process, which is quite stable. Lumbar facet joints gradually form a coronal position from top to bottom. The position, size and shape of bilateral articular processes are not completely symmetrical.

5. The transverse process grows laterally from the lateral posterior side of the vertebral arch. The transverse process of lumbar vertebra is flat and thin in the anteroposterior direction, and gradually increases from the second lumbar vertebra. The third lumbar vertebra is the longest, but the transverse process of the J lumbar vertebra is usually thicker, enlarged on one side or both sides, and rarely symmetrical. More deformed.

6. The laminae on both sides of spinous process are fused in the posterior center to form the base of spinous process. The spinous process is a long flat plate, extending backward and slightly below the vertical. The spinous process of lumbar spine is not on the same longitudinal axis. About 1/2 spinous process is left and right. The spinous process of the fifth lumbar vertebra is often deformed or abnormally developed. The lamina is not closed during ossification. The spinous process is missing and becomes a crack. It may also be a free spinous process, that is, floating spines, or floating spines combined with cracks.