Rod contouring apparatus for percutaneous pedicle screw extension

摘要

Anatomic points within the body are projected outside the body through the use of extenders (180, 182, 188). The projected points may then be used for measurement, or to facilitate the selection or configuration of an implant that is positioned proximate the anatomic points using a slotted cannula (143). Such an implant may be a rod (270) for a posterior spinal fusion system. Pedicle screws (140, 142, 148) may be implanted into pedicles of the spine, and may then serve as anchors for the extenders. The extenders (180, 182, 188) may have rod interfaces (214, 216, 218) that receive the rod (270) in a manner that mimics the geometry of the pedicle screws (140, 142, 148) so that the selected or configured contoured rod (270) will properly fit into engagement with the pedicle screws (140, 142, 148).

主权项

1. A system for configuring or selecting one or more implants and for implanting the implants proximate a bone in the body of a patient, the system comprising:
a first cannula having a proximal end and a distal end, the distal end being adapted to engage a first pedicle fastener implantable in a pedicle of a first vertebra of a spine proximate a first anatomic point, the first pedicle fastener having a first trough, the first cannula defining a first slot and a second slot in a side wall thereof, the first and second slots extending along the first cannula between the proximal and distal ends; a second cannula having a proximal end and a distal end, the distal end being adapted to engage a second pedicle fastener implantable in a pedicle of a second vertebra of the spine proximate a second anatomic point, the second pedicle fastener having a second trough, the second cannula defining a first slot and a second slot in a side wall thereof, the first and second slots extending along the second cannula between the proximal and distal ends; a first simulation member having a proximal end defining a first simulation trough, the first simulation member being configured to attach to the first cannula such that the first simulation trough is positioned outside the body when the first cannula is engaged with the first pedicle fastener implanted in the first vertebra; and a second simulation member having a proximal end defining a second simulation trough, the second simulation member being configured to attach to the second cannula such that the second simulation trough is positioned outside the body when the second cannula is engaged with the second pedicle fastener implanted in the second vertebra; wherein, when the first and second simulation members are attached to the respective first and second cannulas, the first and second simulation members provide a spatial transformation, whereby the first anatomic point is projected to a first projected point proximate the first simulation trough by a projection distance and the second anatomic point is projected to a second projected point proximate the second simulation trough by the projection distance, and the first and second simulation troughs are arranged to receive a rod in a position extending simultaneously through the first and second projected points.