The most widely used and effective lumbar dynamic reconstruction devices are: Coflex Dynamic Stabilization and Isobar Stretch Bar, as well as the lumbar artificial disc. The basic philosophy is to maintain normal lumbar spine motion and minimize the number of fixed segments and the extent of fixation. I. The core principle of the design of the interspinous dynamic fixation device (Coflex Dynamic Stabilization): it is equivalent to the role of internal support, limiting the movement, regulating the stress distribution, and reducing the pressure on the three joints of the lumbar spine segments. Its functions and roles are as follows: (1) to limit the range of motion of lumbar segments; (2) to reduce the pressure on the articular eminence and the intervertebral disc space; (3) to slow down the rate of degeneration of the lumbar intervertebral disc and small articular eminence; (4) to reduce the rate of degeneration of the intervertebral disc in the segments adjacent to the fixed range. Therefore, the main scope of application: 1, combined with the lumbar spine mechanical pain degenerative disorders; back pain can be relieved by rest. 2.Young patients with lumbar disc herniation who need surgical treatment. (1) Lumbar disc herniation combined with lower back pain (mechanical pain, axial pain). (2) Lumbar spinal stenosis combined with lower back pain. (3) Prevention of degeneration of adjacent segments of internally fixed segments (activity limitation, stress distribution regulation). (4) Degenerative slippage within 1°. Contraindications: 1.Sagittal plane displacement instability; Cobb 20° angulation instability. (2) Rotational instability, degenerative scoliosis is not suitable. 3, degenerative slippage, greater than 1°. 4.Smaller spinous process, osteoporosis, heavy manual laborers, overweight. 5, anterior lumbar convexity straightened or posterior convexity with sagittal imbalance (structural change, not functional change). 6.No gap between the spinous processes. Surgical tips: 1. Operate in the flexed position, so that after placement of the Coflex, the following criteria are used for evaluation: the endplates above and below the anterior interspinous space are parallel, not in a posteriorly convex state. 2, If the spinous interspace is narrow and the Coflex cannot be placed, then the Coflex cannot be placed by overpropping the spinous interspace, but by widening the interspinous gap with a grinding drill or a special eminence chisel. 3. When decompression is performed, care is taken not to bite the bone at the base of the spinous process where it is attached to the vertebral plate to avoid destabilizing the spinous process. Second, the design principle of Isobar elastic rod design: based on the design of the artificial joint, which is a restrictive joint Indications are basically the same as Coflex dynamic stabilization device, but more widely applicable than Coflex, more stable. It is particularly suitable for lumbar spine disorders with incomplete plates, small spinous processes, segmental instability, and cases where the application of dynamic reconstruction is indicated, but the application of Corflex is not suitable. Disadvantages: Both the Isobar elastic rod and the Coflex dynamic stabilization device have a certain degree of risk of recurrence of disc herniation. III. Lumbar artificial disc replacement: artificial joint-based design Indication: discogenic pain. Advantages: Preservation of disc motion; complete removal of disc tissue without risk of recurrence of disc herniation. Disadvantages: expensive.