Pedicle screw capable of correcting kyphosis malformation

Abstract

The invention discloses a pedicle screw capable of correcting kyphosis deformity. The pedicle screw comprises a screw body, a screw tail and two blades with internal threads; a first U-shaped concavesurface is machined at the tail end of the screw tail, and a height difference exists between the two ends of the first U-shaped concave surface to form a first continuous slope surface; the pedicle screw comprises a nut, and the nut comprises a threaded block and a pressing block which can be connected in a relative rotating mode; the threaded block is provided with external threads matched withthe internal threads of the blades, and the threaded blocks can rotate and move in the blades in the thread direction; one end of the lower pressing block is connected with the threaded block in a relative rotating mode, the other end of the lower pressing block faces the screw tail, a second U-shaped concave face is machined at the end facing the screw tail, and a height difference exists betweenthe two ends of the second U-shaped concave face to form a second continuous slope, and the inclination directions and inclination angles of the first continuous slope and the second continuous slopeare the same. The accurate reduction of different compression degrees is achieved through the screw tail with different gradients, and kyphosis malformation caused by thoracolumbar vertebral fractureis effectively corrected.

Description

technical field [0001] The invention relates to a pedicle screw, in particular to a pedicle screw capable of correcting kyphotic deformity. Background technique [0002] In recent years, with the development of medicine and biomechanics and the emergence of various new internal fixation devices and methods, pedicle screw reduction and internal fixation has become a common method for the treatment of thoracolumbar fractures. Pedicle screws can penetrate through the anterior, middle and posterior three columns of the spine. Correction of deformities and fixation of injured vertebrae can be achieved through posterior surgery. It has the advantages of small surgical trauma, easy exposure, simple operation, and reliable fixation. Thoracolumbar fractures are mostly flexion-type injuries Whether it is the most common flexion-compression type injury or flexion-distraction type injury, it will cause different degrees of kyphosis in the injured vertebra and adjacent segments. The trad...

AI Technical Summary

Problems solved by technology

Pedicle screws can penetrate through the anterior, middle and posterior three columns of the spine. Correction of deformities and fixation of injured vertebrae can be achieved through posterior surgery. It has the advantages of small surgical trauma, easy exposure, simple operation, and reliable fixation. Thoracolumbar fractures are mostly flexion-type injuries Whether it is the most common flexion-compression type injury or flexion-distraction type injury, it will cause different degrees of kyphosis in the injured vertebra and adjacent segments. The traditional posterior pedicle screw reduction is mostly through distraction or compression The height recovery of the injured vertebra can be achieved by means of the method. Some studies have shown that the average correction degree of the posterior surgery on the sagittal plane is only 1.8°. ability is limited

like Figure 7 As shown, the correction of kyphotic deformity is not obvious despite efforts to propel and reduce

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