Spring piece type cone cavity forming device for fixing vertebral bodyTechnical Field
The invention relates to the technical field of auxiliary instruments for spine reconstruction treatment, in particular to a shrapnel type cone cavity forming device for fixing a vertebral body.
Background
Currently, in the surgical procedures for treating various unstable fracture dislocation of thoracolumbar vertebrae, degeneration of intervertebral disc, spondylolisthesis and kyphosis, it is necessary to fix one or more vertebral bodies above and below the affected part. At present, the upper vertebral body and the lower vertebral body are generally fixed by adopting a mode of matching pedicle screws with connecting rods, namely: firstly, respectively nailing pedicle screws at two sides of a vertebral body of an affected part, wherein the pedicle screws are distributed in an acute angle of ﹀, the other vertebral body is treated in the same way, then the pedicle screws at the same side of the two vertebral bodies are respectively connected and fixed by a connecting rod, and a plurality of vertebral bodies are treated in the same way; the internal fixation of the vertebral body can achieve the purposes of reducing and stabilizing fracture and performing functional exercise in early stage. However, when the vertebral body to be beaten with the pedicle screw is osteoporosis, the pedicle screw can loosen, cut out or withdraw after being beaten into the vertebral body, so that the fixation in the vertebral body is invalid, and the surgical treatment is failed.
Disclosure of Invention
The invention aims to provide a shrapnel cone cavity forming device for fixing a vertebral body, which can improve the fixing effect of a pedicle screw.
In order to achieve the above purpose, the invention adopts the following technical scheme: an elastic piece type cone cavity forming device for fixing a vertebral body, comprising: the pedicle screw is characterized in that a central hole is formed in the axial center of the pedicle screw, a plurality of bone cement diffusion holes communicated with the central hole are formed in the side wall of the front end of the pedicle screw in the circumferential direction, an outer tube main pipe is movably arranged in the central hole, a plurality of outer tube branch pipes communicated with the outer tube main pipe are arranged at the front end of the outer tube main pipe, the outer tube branch pipes are in one-to-one correspondence with the bone cement diffusion holes, each outer tube branch pipe is inserted into the corresponding bone cement diffusion hole, the tube end of each outer tube branch pipe is an elastic tube end with elasticity, the elastic tube end of each outer tube branch pipe is circumferentially divided into a plurality of elastic tube petals, a pull rod is movably inserted into the outer tube main pipe, a plurality of supporting rods are arranged at the front end of the pull rod, the supporting rods are respectively movably inserted into the corresponding outer tube branch pipes and are fixed with the outer ends of all elastic tube petals corresponding to the outer tube main pipe, when the outer tube main pipe pushes the tube ends of the outer tube branch pipes out of the corresponding bone cement diffusion holes, the pull rod drives the corresponding outer tube branch pipes to move inwards, the supporting rods drive all the elastic tube branch pipes to the corresponding outer tube branch pipes to move inwards, the elastic tube ends of the corresponding outer tube branch pipes are driven inwards to bend the corresponding elastic tube main pipe to expand the elastic tube petals outwards around the vertebral pedicle screw to be used for expanding the vertebral pedicle screw outwards.
Further, the above-mentioned elastic piece type cone cavity forming device for fixing a vertebral body, wherein: the outer pipe main pipe and the outer pipe branch pipes are integrally formed, and the pull rod and the support rods are integrally formed.
Further, the above-mentioned elastic piece type cone cavity forming device for fixing a vertebral body, wherein: the pore diameter of the bone cement diffusion pore is gradually reduced from inside to outside.
Through implementation of the technical scheme, the invention has the beneficial effects that: the vertebral body cavities distributed around the vertebral pedicle screws can be formed outside the vertebral pedicle screws driven into the cone, and when bone cement is injected into the vertebral body cavities through the central holes of the vertebral pedicle screws and the bone cement diffusion holes, the bone cement can be uniformly distributed outside the vertebral pedicle screws and effectively fix the vertebral pedicle screws, so that the fixing effect of the vertebral pedicle screws is improved, and the surgical treatment effect is improved.
Drawings
Fig. 1 is a schematic structural view of a shrapnel-type cone cavity forming device for fixing a vertebral body according to the present invention.
Fig. 2 is a schematic view of the structure of the pedicle screw shown in fig. 1.
Fig. 3 is a schematic view of the construction of the outer tube manifold, outer tube branches, tie rods and struts shown in fig. 1.
Fig. 4 is a schematic view of the usage state of fig. 1.
FIG. 5 is a schematic view of the outer tube manifold, outer tube branches, tie rods and struts of FIG. 4 in use.
Detailed Description
The invention will be described in further detail with reference to the drawings and the specific examples.
As shown in fig. 1, 2, 3, 4 and 5, the elastic sheet type cone cavity forming device for fixing a vertebral body comprises: the axial center of the pedicle screw 1 is provided with a central hole 2, the side wall of the front end of the pedicle screw 1 is provided with a plurality of bone cement diffusion holes 3 communicated with the central hole 2 along the circumferential direction, an outer pipe main pipe 4 is movably arranged in the central hole 2, the front end of the outer pipe main pipe 4 is provided with a plurality of outer pipe branch pipes 5 communicated with the outer pipe main pipe, the outer pipe branch pipes 5 are in one-to-one correspondence with the bone cement diffusion holes 3, each outer pipe branch pipe 5 is inserted into the corresponding bone cement diffusion hole 3, the pipe end of each outer pipe branch pipe 5 is an elastic pipe end with elasticity, the elastic pipe end of each outer pipe branch pipe 5 is divided into a plurality of elastic pipe flaps 51 along the circumferential direction, a pull rod 6 is movably inserted into the outer pipe main pipe 4, the front end of the pull rod 6 is provided with a plurality of supporting rods 7, the struts 7 of the pull rod 6 are in one-to-one correspondence with the outer tube branch pipes 5 of the outer tube main pipe 4, each strut 7 of the pull rod 6 is movably inserted into the corresponding outer tube branch pipe 5 and is fixed with the outer ends of all the elastic tube petals 51 at the tube ends of the corresponding outer tube branch pipe, when the outer tube main pipe 4 pushes the tube ends of the outer tube branch pipes 4 out of the corresponding bone cement diffusion holes 3, the pull rod 6 drives each strut 7 to move inwards relative to the corresponding outer tube branch pipe 4, each strut 7 drives the outer ends of all the elastic tube petals 51 of the corresponding outer tube branch pipe 5 to move inwards, and all the elastic tube petals 51 of the corresponding outer tube branch pipe 5 are simultaneously bent outwards and expanded, so that a plurality of vertebral body cavities 9 which are distributed around the pedicle screw 1 and used for pouring bone cement are expanded in vertebral bodies 8 outside the pedicle screw 1; in the embodiment, the outer pipe main pipe 4 and the outer pipe branch pipes 5 are integrally formed, and the pull rod 6 and the support rods 7 are integrally formed, so that the use safety can be improved; in the embodiment, the aperture of the bone cement diffusion holes 3 is gradually reduced from inside to outside, so that the flow rate of bone cement can be increased in the process of passing through the bone cement diffusion holes 3, thereby enabling the bone cement to be injected into the cavities of each vertebral body more rapidly and improving the operation efficiency;
during the internal fixation operation of the cone, the pedicle screws 1 are completely nailed into the vertebral body 8 along the nail feeding direction, and the two pedicle screws are distributed in an acute angle shape of ﹀; then the pipe ends of the outer pipe branch pipes 4 are pushed out of the corresponding bone cement diffusion holes 3 through the outer pipe main pipe 4, then the struts 7 are driven to move inwards relative to the corresponding outer pipe branch pipes 4 through the pull rods 6, and all the elastic pipe petals 51 of the corresponding outer pipe branch pipes 5 are synchronously driven to move inwards when the struts 7 move inwards, so that all the elastic pipe petals 51 of the corresponding outer pipe branch pipes 5 are simultaneously bent and expanded outwards, and a plurality of vertebral body cavities 9 which are distributed around the pedicle screws 1 and used for pouring bone cement are expanded in vertebral bodies 8 outside the pedicle screws 1;
then the pedicle screw 1 is rotated for one turn, all the elastic tube petals 51 of each outer tube branch tube 5 of the expanded protruding pedicle screw 1 are driven to rotate for one turn around the pedicle screw 1, and a plurality of annular vertebral body cavities surrounding the pedicle screw are swept out in the vertebral body 8 outside the pedicle screw 1 through all the elastic tube petals 51 of each outer tube branch tube 5;
then, each supporting rod 7 is driven to move outwards relative to the corresponding outer tube branch 4 through the pull rod 6, when each supporting rod 7 moves outwards, the outer ends of all the elastic tube petals 51 corresponding to the outer tube branch 5 are synchronously driven to move outwards, so that all the elastic tube petals 51 corresponding to the outer tube branch 5 simultaneously return to a collapse state capable of retracting the bone cement diffusion holes 3, then, the outer tube main tube 4, the outer tube branch 5, the pull rod 6 and the supporting rod 7 are simultaneously pulled out of the pedicle screw 1, and at the moment, a plurality of rings of annular vertebral cavities surrounding the pedicle screw are formed in the vertebral body 8 outside the pedicle screw 1;
then injecting bone cement into the pedicle screw 1 from the central hole 2 of the pedicle screw 1, and continuously rotating the pedicle screw 1 in the gradual curing process of the bone cement after the bone cement flows into the corresponding annular vertebral body cavities from the central hole 2 of the pedicle screw 1 through the bone cement diffusion holes 3 until the bone cement in the annular vertebral body cavities forms internal threads matched with the external threads of the corresponding pedicle screw 1; after the bone cement is completely solidified, the fixation of the pedicle screw is realized; because the bone cement forms the internal thread matched with the external thread of the pedicle screw, the pedicle screw 1 can more conveniently withdraw from the vertebral body after the treatment is finished, thereby reducing the damage to the vertebral body of the patient and further improving the treatment effect of the operation.
The invention has the advantages that: the vertebral body cavities distributed around the vertebral pedicle screws can be formed outside the vertebral pedicle screws driven into the cone, and when bone cement is injected into the vertebral body cavities through the central holes of the vertebral pedicle screws and the bone cement diffusion holes, the bone cement can be uniformly distributed outside the vertebral pedicle screws and effectively fix the vertebral pedicle screws, so that the fixing effect of the vertebral pedicle screws is improved, and the surgical treatment effect is improved.