Lumbar vertebra posterior internal fixation device

The utility model relates to a lumbar vertebra posterior internal fixation device, which comprises pedicle screws, a positioning block, positioning rings, a screw and a connecting rod, wherein the pedicle screws are implanted in pediculus arcus vertebrae of vertebra of patient in order to play the role of anchoring and provide three-dimensional correction and firm internal fixation, the positioning block is positioned between the pedicle screws and the screw to be bridge arc-shaped, and the positioning block creates slide with the connecting rod owing to smooth internal surface, the positioning rings are positioned at two ends of the fixation device and are used for preventing lumbar vertebra from excessive flexion and distraction, the screw is positioned at the upper part of the pedicle screw and used for fixing the positioning block and the connecting rod, and the connecting rod is used for the connection with various pedicle screws so as to play the role of fixation. The device of the utility model has the characteristics that: long segment spine dynamic internal fixation is adopted for dislocation-type lumbar vertebra fracture, which can not only guarantee effective fixation strength to recover the stability of spine, but also prevent degenerative diseases on fixed segments and adjacent segments so as to protect intervertebral disc tissue and favor postoperative rehabilitation.