Surgery – Instruments – Orthopedic instrumentation
Reexamination Certificate
1998-09-04
2001-02-06
Mancene, Gene (Department: 3732)
Surgery
Instruments
Orthopedic instrumentation
Reexamination Certificate
active
06183477
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to drill guides and other medical instruments that are attached to medical implants such as intramedullary nails which assist in the performance of surgical steps such as targeting and guiding the installation of bone screws from outside the body. More particularly, the invention is directed to a tool that facilitates the detachment of drill guides and the like from medical implants and minimizes the time to perform the detachment step and the size of the incision through body tissue in the vicinity of the implant.
2. Description of the Prior Art
During a procedure to insert an intramedullary nail, a drill guide is connected to the intramedullary nail with a connecting bolt. The connecting bolt is threaded into the proximal end of the intramedullary nail aligned generally with the longitudinal axis of the intramedullary nail. During insertion of the intramedullary nail into the patient, a mallet is used to strike an insertion driver which communicates the impact through the drill guide to the intramedullary nail. After insertion of the intramedullary nail, the drill guide provides alignment for drilling transverse bores through the bone to accommodate transverse screws to lock the intramedullary nail to the bone. In addition, other orthopedic devices that require precise alignment or sturdy connection to the intramedullary nail, such as drills, modular drill guides, reaming devices, guide tubes, guide pins, fasteners, or removal drivers, can be attached to the drill guide.
The connection of the drill guide to the intramedullary nail is an important part of the femoral shaft fracture procedure. The connecting bolt is often obscured by soft tissue and cannot be seen by the surgeon. Getting a tool to the connecting bolt can be difficult, may require several minutes, and often results in soft tissue damage. In addition, a large incision is often required to accommodate the required tool. An example of such a drill guide showing a conventional attachment is disclosed in U.S. Pat. No. 4,911,153.
One prior art device, the Synthes drill guide, allows remote actuation of the connecting bolt. However, the Synthes device achieves remote actuation through a long, bent neck for guiding a universal-jointed driving tool to the bolt. The neck is permanently attached and continuously interferes with soft tissue during the medical procedure. In addition, the bolt used with the Synthes device is not cannulated. Cannulation of the bolt is desirable to allow the surgeon access to the interior of an implant.
It is an object of the present invention to provide an attachment tool for an implant drill guide that can be remotely actuated with minimal soft tissue damage. It is a further object of the present invention to provide an attachment tool that is capable of using cannulated fasteners. These objects are solved by the attachment tool of the present invention.
SUMMARY OF THE INVENTION
The problems discussed above have been solved by providing an attachment tool for use with a medical implant such as an intramedullary nail which includes a housing having a first end adapted for connection to a medical implant. The first end includes a first opening through which passes an elongated threaded fastener such as a bolt or screw that is designed to be inserted into an elongated opening in the implant. The housing includes a guide surface and may include a second opening that intersects and is offset from the first opening for guiding a driving tool into contact with the fastener at an angle offset from the axis of the fastener. The housing is designed to minimize the size of the necessary incision in the body tissue while facilitating connection of drill guides and other orthopedic devices. The housing may have various shapes depending upon the shape of the implant, drill guide or other orthopedic device to which it connects. In the case of a drill guide for an intramedullary nail, the housing is preferably U-shaped, L-shaped, or S-shaped.
The first end includes a tab or other type of alignment and positioning member for engaging a slot or the like formed in the proximal end of an implant such as an intramedullary nail. When the tab is aligned with the slot, the first opening is aligned with the opening in the intramedullary nail so that the threaded fastener can easily be inserted in the nail opening through the first opening. Tab and slot alignment also assures that holes drilled using the integral drill guide holes or an attached drill guide align with implant fastening holes.
The fastener is preferably a bolt with a female hexagonally-shaped driving head. The driving tool, on the other hand, has a driving head that is adapted to engage and drive the fastener from a angle offset relative to the axis of the fastener. One example of such a driving head is a rounded male hexagonally-shaped driving head that is designed to cooperate with the hexagonally-shaped female driving head on the fastener.
The guide surface for the driving tool can include a groove for receiving the driving tool and guiding it to an opening in the housing. Said opening could be the first opening, but is preferably a second opening that intersects the first opening at a point where the driving tool can extend through the second opening and engage the fastener for driving it into place. If the fastener is cannulated, i.e., has an opening along its axis, a guide rod can be inserted through the fastener to help reduce the fracture during surgery.
The tool can include one or more drill guide hole(s) in the guide housing aligned with openings in the implant when the guide housing is connected to the implant for targeting a drill to form openings in the tissue and bone around the implant to receive implant fastening screws. The drill guide holes could alternatively be formed in an attachment for the tool instead of being formed in the tool itself.
A tool of the type generally described can be used to guide and align a driving tool to a fastener more quickly and with less damage to tissue surrounding an implant than in prior art devices. Moreover, with a cannulated fastener, the tool allows a guide rod to be inserted for fracture reduction.
REFERENCES:
patent: 4103683 (1978-08-01), Neufeld
patent: 4465065 (1984-08-01), Gotfried
patent: 4622959 (1986-11-01), Marcus
patent: 4733654 (1988-03-01), Marino
patent: 4862883 (1989-09-01), Freeland
patent: 4911153 (1990-03-01), Border
patent: 4913137 (1990-04-01), Azer et al.
patent: 5047034 (1991-09-01), Sohngen
patent: 5176681 (1993-01-01), Lawes et al.
patent: 5178621 (1993-01-01), Cook et al.
patent: 5295991 (1994-03-01), Frigg
patent: 5334192 (1994-08-01), Behrens
patent: 5346496 (1994-09-01), Pennig
patent: 5352228 (1994-10-01), Kummer et al.
patent: 5429641 (1995-07-01), Gotfried
patent: 5458600 (1995-10-01), Stapert et al.
patent: 5478341 (1995-12-01), Cook et al.
patent: 5713902 (1998-02-01), Friedl
patent: 5728128 (1998-03-01), Crickenberger et al.
patent: 5741266 (1998-04-01), Moran et al.
Synthes; The Titanium Unreamed Femoral Nail System; published in the Original Instruments and Implants of the Association for the Study of Internal Fixation—AO/ASIF.
Fulbright & Jaworski L.L.P.
Mancene Gene
Robert Eduardo C.
Smith & Nephew Inc.
LandOfFree
Attachment tool for drill guide does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Attachment tool for drill guide, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Attachment tool for drill guide will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2565477