Split dynamic and static dual-purpose pedicle screw and mounting tool thereof

Abstract

A split type dynamic and static dual-purpospedicle screw capable of being fused or fixed in a non-fused mode and assembled in an operation is used for a spinal internal fixation operation, and is composed of a screw base (1), a connecting claw (4), a ball screw (10), an auxiliary connecting rod (13) and a locking screw (14) which are assembled in the operation. The screw base (1) is provided witha circular hollow cavity, an open through groove (2) for restraining the connecting rod (13) is formed in the top end or the side wall of the screw base (1), and the lower end of the screw base (1) isan umbrella-shaped opening (3); the upper half portion of the connecting claw (4) is a hollow cylindrical body (5) connected with the screw base (1), the lower half portion of the connecting claw (4)is an umbrella-shaped body (6), an annular deformation groove (9) is formed in the outer surface of the joint, the umbrella-shaped body (6) is evenly divided into a plurality of petals (8) capable ofbeing opened outwards, and a spherical cavity (7) is formed inside. During an operation, the ball screw (10) is implanted into the pedicle of the vertebral arch, then the inner cavity of the umbrella-shaped body (6) at the lower end of the connecting claw (4) wraps the ball head part (11), the screw base (1) is sleeved in the connecting claw (4) and is connected with the connecting claw (4) through a threaded structure, and finally the connecting rod (13) is inserted into the open through groove (2) and locks threaded connection. The incisura of the pedicle screw is extremely low, so that discomfort such as pain and the like caused by muscle stimulation of a highly convex implant can be greatly reduced.

Description

technical field [0001] The invention relates to a human body implant used in orthopaedics or neurosurgery in the field of medical instruments, in particular to a split dynamic and static dual-purpose pedicle screw and an installation tool thereof. Background technique [0002] With the development of biomechanical research and material science, the application of internal fixation technology has become more and more extensive. The pedicle screw rod fixation system currently used in orthopedic surgery is composed of several pedicle screws connected to each vertebral arch. The pedicle screw is composed of the connecting rod of the root screw, and the pedicle screw is composed of a conjoined screw seat, a screw body and a separate locking screw. [0003] During the operation, firstly use tools to connect the screw bases and screw the nails into the pedicles of different vertebrae, then use connecting rods to connect the screw bases of each pedicle screw on the same side of the ...

AI Technical Summary

Problems solved by technology

The former means that the system has sufficient rigidity and can completely limit the movement of the fixed segment. It is a static fixation method. The pedicle screw with this function is called a "fixed screw"; the latter deliberately retains the proper space between the fixed segments. It is a dynamic fixation method, in order to achieve the purpose of reducing the stress concentration of adjacent segments, and the pedicle screw body under the dynamic fixation method can still obtain dynamic activities relative to the connecting rod after the fixation operation is completed, so it is also It is called "dynamic nail", but these non-fused dynamic nails all have the disadvantages of large nail base and many parts.

[0005] In addition, at present, whether it is a static or dynamic pedicle screw, the screw base and the screw body have been assembled and integrated before the operation. When the pedicle screw is implanted, the thick screw base blocks the It is difficult for doctors to accurately judge whether the implantation depth is just right due to the observation of the relatively small screw neck. If the implantation is too deep, the tip of the screw will penetrate the front edge of the vertebral body and endanger the safety of large blood vessels, or if the implantation is too shallow, the fixation strength will be reduced. It is not uncommon in clinical

Once these situations occur, if the implantation is too shallow, the fixation rod can be removed and then screwed deeper for re-fixation, which only prolongs the operation time and increases the risk of bleeding and infection; but if the implantation is too deep and then removed, not only the above disadvantages, Back-tightening of the pedicle screw will greatly reduce the fixation strength of the screw channel and reduce the quality of the operation.

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