Abstract: A positioning insert for two adjacent vertebral bodies includes a plate like insert adapted to fix relative positions of the two adjacent vertebral bodies and provided with a sharp edge oppositely formed relative to the dull side and first holes defined through a side face of the plate like insert, wherein the sharp edge is formed to have an angle between 5 to 15 degrees; and an annular insert adapted to be inserted into a space between the two adjacent vertebral bodies and having second holes and a slot defined in a peripheral side face thereof to accommodate the plate like insert so as to have the plate like insert received in the slot.

Abstract: A composite layer intervertebral retrieving device implantable between two vertebrae is provided, including a main carrier having a middle layer, and a securing groove on respective surfaces; multiple securing pieces stably coupled to the securing grooves; wherein the middle layer is a macromolecular material having an elastic modulus of between 2 to 22 GPa, close to the original elastic modulus of the spine of between 12 to 18 GPa. The securing pieces are affinitive to and easily fused with osteocytes, and capable of medically imaging. The securing pieces are coupled to the securing grooves, and when the device is implanted between vertebrae, the securing pieces come into direct contact with the osteocytes of the neighboring vertebrae, with securing bulges thereof pressing against the osteocyes, and the middle layer has an elastic modulus similar to that of the vertebrae to prevent the stress shielding effect.

Abstract: A plug-type spinal retrieving device includes a retrieval rod; a fastening screw assembly including a fastening screw and a C-shaped ring having a convex outer surface; a plug; and a fixation seat having a receiving hole in which the retrieval rod is slidably received, a fastening hole having a concave wall in which the C-shaped ring is rotatably received, and an interconnecting hole through which the receiving hole communicates with the fastening hole. The C-shaped ring is mounted on the fastening screw, so that the fastening screw is grasped by the C-shaped ring, when the C-shaped ring is received in the fastening hole of the fixation seat. The C-shaped ring and the retrieval rod are immobilized in the fastening hole and the receiving hole of the fixation seat by inserting the plug into the interconnecting hole.

Abstract: A vertebral retrieval device includes a retrieval rod which is gripped firmly in a receiving slot of a fixation seat between two grooves of a pressing element and a C-shaped ring. The C-shaped ring rests on a spherical head fastening screw, a spherical head of which is received in the fixation seat and a shank of which is protruding from a through hole provided in a bottom of the fixation seat. The pressing element is pressed against the retrieval rod by a pressing screw, which is threaded into a threaded hole formed in a fixation element mounted in the receiving slot of the fixation seat.

Abstract: A vertebral retrieval device includes a retrieval rod which is gripped firmly in a receiving slot of a fixation seat between two grooves of a pressing element and a C-shaped ring. The C-shaped ring rests on a spherical head fastening screw, a spherical head of which is received in the fixation seat and a shank of which is protruding from a through hole provided in a bottom of the fixation seat. The pressing element is pressed against the retrieval rod by a pressing screw, which is threaded into a threaded hole formed in a fixation element mounted in the receiving slot of the fixation seat.

Abstract: A plug-type spinal retrieving device includes a retrieval rod; a fastening screw assembly including a fastening screw and a C-shaped ring having a convex outer surface; a plug; and a fixation seat having a receiving hole in which the retrieval rod is slidably received, a fastening hole having a concave wall in which the C-shaped ring is rotatably received, and an interconnecting hole through which the receiving hole communicates with the fastening hole. The C-shaped ring is mounted on the fastening screw, so that the fastening screw is grasped by the C-shaped ring, when the C-shaped ring is received in the fastening hole of the fixation seat. The C-shaped ring and the retrieval rod are immobilized in the fastening hole and the receiving hole of the fixation seat by inserting the plug into the interconnecting hole.