摘要 |
An improved apparatus is provided to reduce the extent of displacement between adjacent vertebrae in a person's spinal column and to subsequently maintain the vertebrae in a reduced displacement relationship. When the apparatus is to be installed, holes are formed in the displaced vertebra and in vetebrae on opposite sides of the displaced vertebra. Force transmitting members are mounted in the holes in the vertebrae. A spinal plate is then positioned on the spinal column with the force transmitting members extending outwardly through slots in the spinal plate. Nuts are tightened on the force transmitting members connected with vertebrae on opposite sides of the displaced vertebra to anchor the spinal plate in place. A nut on the force transmitting member connected with the displaced vertebra is then tightened to pull the displaced vertebra to a desired position. In one embodiment of the invention, the force transmitting member has a relatively large diameter helix which engages a side wall of the hole in the displaced vertebra. In another embodiment of the invention, an insert is positioned in a hole in the displaced vertebra and expanded by the force transmitting member to securely grip the vertebra.
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