Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B17/00—Surgical instruments, devices or methods
  • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
  • A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws or setting implements
  • A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
  • A61B17/70—Spinal positioners or stabilisers, e.g. stabilisers comprising fluid filler in an implant
  • A61B17/7049—Connectors, not bearing on the vertebrae, for linking longitudinal elements together
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B17/00—Surgical instruments, devices or methods
  • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
  • A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws or setting implements
  • A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
  • A61B17/70—Spinal positioners or stabilisers, e.g. stabilisers comprising fluid filler in an implant
  • A61B17/7001—Screws or hooks combined with longitudinal elements which do not contact vertebrae
  • A61B17/7041—Screws or hooks combined with longitudinal elements which do not contact vertebrae with single longitudinal rod offset laterally from single row of screws or hooks
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B17/00—Surgical instruments, devices or methods
  • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
  • A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws or setting implements
  • A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
  • A61B17/70—Spinal positioners or stabilisers, e.g. stabilisers comprising fluid filler in an implant
  • A61B17/7047—Clamps comprising opposed elements which grasp one vertebra between them
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B17/00—Surgical instruments, devices or methods
  • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
  • A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws or setting implements
  • A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
  • A61B17/70—Spinal positioners or stabilisers, e.g. stabilisers comprising fluid filler in an implant
  • A61B17/7056—Hooks with specially-designed bone-contacting part

Definitions

• Hook for vertebral osteosynthesis device and device comprising it.
• the invention relates to the field of prostheses intended to be implanted on the spine of a patient, called vertebral osteosynthesis devices.
• Different pathologies may require the implantation of such a device, such as damage to the vertebrae and / or disks separating them, following a degenerative disease, a tumor or trauma, or a misalignment of the vertebrae with respect to their positions. normal. They aim to secure two consecutive vertebrae or more in a specific relative position.
• longitudinal elements such as elongated rods or plates, extending along the vertebral column and attached to the vertebrae by various means are often used.
• the longitudinal elements may be attached to the column according to an anterior surgical approach or a posterior surgical approach. Both approaches have their advantages and disadvantages, and the surgeon's choice must be made according to the particular needs of the patient.
• the anterior approach may be particularly indicated when the vertebrae of the patient have a non-pathological internal structure, for example an absence of osteoporosis affecting the cancellous bone, which makes it possible to implant bone screws to which are connected (directly or through the intermediate connectors) the longitudinal elements.
• the posterior approach may be more appropriate in cases where osteoporosis weakens the spongy part of the vertebrae and makes it risky to implant bone screws in areas where the cancellous bone is particularly thick as is the case in the anterior part. vertebrae. In this case, we can take advantage of the vertebral processes to implant on the posterior vertebrae hooks engaging on these processes, these hooks themselves carrying elements for connecting a longitudinal element.
• the object of the invention is to provide a device for fixing a longitudinal element by the posterior route whose design is simple and easy to install, requiring only as little intervention time as possible.
• the subject of the invention is a hook, intended to be implanted on the isthmic part of a vertebra, and comprising a lower part and a part upper, connected by an intermediate portion substantially perpendicular to the lower and upper parts, and intended to extend, when the hook is attached to a vertebra, along the outer face of the isthmic portion of said vertebra, a clamping piece can to be secured to a rod inserted into an orifice and passing through the upper part of the body, non-return means being provided to prevent extraction of the rod from the orifice after insertion, and means for securing the a longitudinal member of a spinal osteosynthesis device to said rod.
• Said means for securing a longitudinal element of a spinal osteosynthesis device to said rod may comprise a connector fitted on the rod and means for clamping said connector on the upper part of the hook.
• Said rod and said connector can be oriented in relation to one another in a polyaxial manner.
• the connection between the rod and the clamping piece may be polyaxial.
• It may comprise means allowing the connection of two hooks located on the two isthmic parts of the same vertebra.
• Said means allowing the connection of two hooks located on the two isthmic parts of the same vertebra may comprise an appendage oriented substantially perpendicular to the upper part of the hook, and having an orifice to be traversed by a connecting rod and means of locking said connecting rod in said orifice.
• the rod may have a thread and the hole of the hook may have a thread corresponding to that of the rod, said threads constituting said non-return means.
• the subject of the invention is also a vertebral osteosynthesis device, comprising at least one longitudinal element and fastening elements of this longitudinal element on at least two consecutive vertebrae, characterized in that at least one of said fastening elements is a hook of the previous type. It may comprise at least two hooks intended to be implanted on the same vertebra and having means for their connection, and connection means to each other of said hooks.
• the invention is based on the use of a hook intended to be implanted laterally, on an isthmic part of a vertebra, by simply clamping said isthmic part between the upper and lower parts of the hook.
• FIG. 1 which shows in exploded perspective the main parts of an example of a vertebral osteosynthesis device hook according to FIG. invention
• FIG. 2 which shows exploded perspective the main parts of an exemplary vertebral osteosynthesis device according to the invention
• FIG. 5 which shows in perspective in the assembled state an example device according to the invention intended to be implanted on a vertebra and having two hooks according to the invention connected by a connecting rod;
• FIG. 6 which shows in perspective an example of vertebral osteosynthesis device according to the invention implanted on two vertebrae;
• Figure 7 shows another variant of the hook according to the invention, implanted on a vertebra.
• Figure 1 shows in exploded view a first example of isthmic hook used in the context of the invention. It contains the elements that we will enumerate.
• a body 1 forming a hook having a lower portion 2 and an upper portion 3, connected by an intermediate portion 4 intended to extend, when the hook is attached to a vertebra, along the outer face of the isthmic part of said vertebra.
• the lower part 2 is intended to be inserted against the lower face of the isthmic part, and the upper part 3 is intended to come above the upper face of the same. isthmic part, as seen in Figure 6. They are each substantially perpendicular to the intermediate portion 4.
• the tightening of the body 1 against the vertebra is provided by a clamping piece in the general form of disc 5 (in the example shown ) can be secured to a threaded rod 6 inserted in an orifice 7 having a corresponding thread and passing through the upper part 3 of the body 1, at a spherical dome 8 on which is intended to rest a connector 9 to connect the body 1 of the hook to a longitudinal rod 10.
• the fastening of the disc 5 and the threaded rod 6 is provided by two screws 11, 12 intended to be inserted into a groove 13 formed at the lower end of the threaded rod 6 , as can be seen in FIG. 4.
• the body 1 also comprises, in the example shown, an appendage 14 oriented substantially perpendicularly to the upper part 3 of the body 1 forming an eighth t.
• Appendix 14 has an orifice 15 to be traversed by a connecting rod 16 for connecting the body 1 to a body similar to him and disposed symmetrically to him on the other isthmic portion of the vertebra.
• a threaded orifice 17 makes it possible to introduce a clamping screw 18 to block the rod 16 in the orifice 15.
• Figure 2 shows an exploded view of the main parts of a complete device including the elements which have just been described, and intended to be implanted on both sides of the same vertebra. It shows in particular the configuration of the connector 9, which is of a type known in itself. It comprises an orifice 19 for insertion of the longitudinal rod 10 to be connected to the hook 1 and an orifice 20 for inserting the connector 9 on the rod 6.
• the lower face 21 of the connector 9 is shaped to rest on the dome spherical 8 of the body 1.
• the connector 9 also has a slot 22 putting in communication the two orifices 19, 20, so that, when the rod 10 is inserted into the orifice 19, a tightening nut 23 threaded onto the rod 6 causes a ruzement of the walls of the orifice 19, thus a clamping and locking of the longitudinal rod 10.
• FIG. 3 and 4 show the hook 1 and connector 9 assembled (without the rods 10, 16). It is seen, in particular, in the sectional view of FIG. 4 how the screws 11, 12 (not shown in FIG. 2) make it possible to secure the disc 5 and the threaded rod 6.
• Clamping of the hooks 1 against the isthmic parts of the vertebra is ensured by a rotation of the threaded rod 6 performed by the surgeon with the aid of a conventional tool engaging the upper end 24 of the rod 6, so as to bring the disk 5 in contact with the vertebra.
• the disc 5 is, in the example shown, in free rotation relative to the rod 6 and can easily come to take its best position on the vertebra.
• the disk shape of this clamping piece 5 shown in the drawings is in no way limiting and may be modified, in particular to better adapt its underside to the precise configuration of the part of the vertebra on which it is intended to 'to press.
• the connection between the rod 6 and the disk 5 could be of a type other than that shown in the figures, providing the same functionality, such as a ball joint. In general, it is preferable to provide a polyaxial connection between the rod 6 and the disk 5.
• FIG. 5 shows two hooks 1, each assembled with a connector 9 and a rod 6, and connected by a rod 16. It can also be seen that the upper parts of the threaded rods 6 and nuts 23 have been removed in order to limit the size of the device after his pose. This is also the case, preferably, for the upper part of the clamping screw 18 of the rod 16. This can be achieved, in a conventional manner, by providing on these different members areas of least resistance that break during their tightening as soon as a sufficient tightening torque is reached.
• FIG. 6 shows the implantation of this exemplary device according to the invention on a vertebra 24. The hooks 1 are tight on the isthmic parts 25 of the vertebra 24, and the connecting rod 16 passes behind the spinous process 26.
• the longitudinal rods 10 are fixed to the next vertebra 27 by passing through the head 28 of a pedicle screw 29 fixed in said vertebra 27 and locked by a clamping screw 30 of conventional type.
• a device similar to that of the invention or by any other suitable device could also extend, if necessary, to a larger number of vertebrae.
• a caudal hook 31 anchored in the caudal region of the vertebra is represented the case where the caudal hook 31 is substituted for the appendix 14 and, therefore, the hooks 1 located on the two isthmic parts of the same vertebra are not connected to each other.
• a caudal hook 31 is particularly useful if one wishes to install longitudinal rod 10 on one side of the spine, in that it improves the rigidity of the entire device.
• the rod 6 preferably has at least one flat 32 which, in cooperation with a corresponding form of the orifice 20 of the connector 9, prevents rotation of the connector 9 after its introduction.
• the threading of the rod 6 and the corresponding thread of the orifice 7 of the body 1 can be replaced by any non-return means making it possible to avoid the extraction of the rod 6 after it has been inserted into the orifice 7, for example teeth placed on the rod 6 and elastic strips placed in the orifice 7, the respective shapes would be adapted to obtain such a non-return effect.
• the longitudinal rod 10 may be replaced by another type of longitudinal element such as an elongate plate.
• any means could be used to secure the rod 6 and the longitudinal member 10, for example at the upper end of the threaded rod 6 a receptacle for the longitudinal member 10 and means, such as a threaded plug cooperating with a corresponding thread of the walls of the receptacle, for maintaining the longitudinal member in the receptacle.
• the assembly formed by the appendix 14 and the connecting rod 16 may be replaced by any functionally equivalent means allowing the connection of two hooks 1 located on the two isthmic parts of the same vertebra.
• the device according to the invention can be used in particular, but not exclusively, in the thoracic region of the spine.

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• Health & Medical Sciences (AREA)
• Orthopedic Medicine & Surgery (AREA)
• Life Sciences & Earth Sciences (AREA)
• Neurology (AREA)
• Surgery (AREA)
• Heart & Thoracic Surgery (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Medical Informatics (AREA)
• Molecular Biology (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Surgical Instruments (AREA)

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• 2008
  • 2008-05-02 FR FR0852966A patent/FR2930719B1/fr not_active Expired - Fee Related
• 2009
  • 2009-05-04 EP EP09738552A patent/EP2288302A1/de not_active Withdrawn
  • 2009-05-04 WO PCT/IB2009/051819 patent/WO2009133539A1/fr not_active Ceased

Non-Patent Citations (1)

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