Patent Application
20230355409
This invention relates generally to an orthopaedic implant tool interfacing socket.
Orthopaedic implants generally require a feature to allow a surgeon to manipulate the implant into position. For example, femoral prosthetic devices for hip arthroplasty are inserted into a patient's femur with an impacting tool interfacing the prosthetic device.
Some implants comprise an indentation which locates a tip of an insertion tool which may then be impacted to drive in the implant.
Other implants comprise a threaded socket into which an insertion tool is screwed which may also assist the extraction of the implant. For example, US 20180311050 A1 (DEPUY SYNTHES PRODUCTS, INC.) 1 Nov. 2018 discloses an implant having neck proximal end portion with an insertion/extraction cavity which engages a threaded shaft of an instrument for insertion or extraction.
However, threading may be damaged by inadvertent cross threading or by the insertion tool not being correctly seated during impaction.
Damaged threading may prevent or hinder disengagement of the insertion tool or, worse, removal of the implant as may be required during initial or revision surgery.
The present invention seeks to provide a way to overcome or substantially ameliorate at least some of the deficiencies of the prior art, or to at least provide an alternative.
It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country.
There is provided herein an orthopaedic implant tool interfacing socket for an orthopaedic implant which has a stage spaced from an entrance of a threaded blind hole thereunderneath. The stage at least partially defines an impaction face, a keyed entrance therethrough and an extraction tool engagement edge thereunderneath being out of rotational alignment with the keyed entrance.
The impaction face is preferably indented and may be hemi-spheroidal.
The threading is protected deep within the socket which may avoid cross threading and/or incorrect tool seating.
An insertion tool having a rod having a widened portion at a distal end thereof may be used to impact the impaction surface from differing angles to, for example, manipulate the implant around corners as may sometimes be required for direct anterior approach insertion of hip implants.
The widened portion and the impaction surface may be hemi-spherical to equally allow for impaction from various angles or non-hemi-spherical such as being hemi-elliptical to bias the insertion tool within an impaction angle range.
An insertion tool further comprising a distal threaded rod tip extending distally from the widened portion may screw into the threading of the threaded blind hole wherein and the widened portion abuts against the impaction face to take a load off the threading.
Furthermore, a rotation tool comprising a key fitting and locating within the keyed entrance may be used to control the version of the implant.
Furthermore, an extraction tool comprising a key fitting through the keyed entrance may be used to engage the extraction tool engagement edge to quickly and easily remove the implant.
According to one aspect, there is provided apparatus comprising an orthopaedic implant comprising an orthopaedic implant tool interfacing socket, the socket having a stage spaced from an entrance of a threaded blind hole thereunderneath, the stage at least partially defining an impaction face, a keyed entrance therethrough and an extraction tool engagement edge thereunderneath being out of rotational alignment with the keyed entrance.
The impaction face may be indented. The impaction face may be hemi-spheroidal. Alternatively, the impaction face may be non-hemi-spheroidal, such as hemi-elliptical.
In cross-section perpendicular with a longitudinal axis of the blind hole, the keyed entrance may comprise a central section being larger in cross-section than that of the threaded blind hole. The central section may be circular in cross-section.
In cross-section perpendicular with a longitudinal axis of the blind hole, the keyed entrance may be elongate in cross-section wherein the keyed entrance may define a pair of slots diametrically opposite the central section.
The socket may define a frustoconical lead-in from beneath the stage into the threaded blind hole.
The apparatus may further comprise an insertion tool comprising a rod and a widened section at a distal end thereof and wherein the insertion tool engages the socket such that the widened section fits the impaction face thereof.
The insertion tool may comprise a threaded rod tip extending distally from the widened section which screws into the threaded blind hole. The threaded rod tip may screw into the threaded blind hole until the widened section abuts the impaction face.
The impaction face and the widened section may be hemi-spheroidal. Alternatively, the impaction face and the widened section are non-hemi-spheroidal such as hemi-elliptical.
The apparatus may further comprise an extraction tool comprising a rod and a key at a distal end thereof, the key shaped to fit through the keyed entrance and engage under the extraction tool engagement edge when rotated out of alignment with the keyed entrance.
The apparatus may further comprise a rotation tool comprising a rod and a key at a distal end thereof, the key shaped to fit into the keyed entrance and wherein the rotation tool has a feature which locates the key within the keyed entrance when the rotation tool may be pressed into the socket.
The feature may comprise a platform above the key which abuts against the impaction face.
There are also provided methods for inserting, extracting and rotating an implant having the socket with the various tools.
Other aspects of the invention are also disclosed.
Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:
The socket 100 may however be applied to other types of orthopaedic implants requiring insertion and/or extraction.
With reference to
The spacing of the stage 105 from the entrance of the blind hole 106 may form a void 107 therebetween. The socket 100 may comprise a slight frustoconical lead-in 111 from the void 107 into the threaded blind hole 106.
The stage 105 at least partially defines an impaction face 108 and a keyed entrance 109 therethrough. The stage 105 further defines an extraction tool engagement edge 110 thereunderneath being out of rotational alignment with the keyed entrance 109.
The impaction face 108 is preferably indented. The impaction face 108 may be hemi-spheroidal. In one embodiment, the impaction face 108 may be hemi-spherical (i.e., forming part of a sphere of constant radius). In alternative embodiments, the impaction face 108 may be non-hemi-spherical such as being hemi-elliptical.
As is best shown in
In embodiments, a rotation tool (not shown) may be employed which comprises a key which is shaped to fit and locates within the shaped entrance 109. The rotation tool may comprise a feature which locates the key within the shaped entrance 109. For example, the rotation tool may comprise a platform above the key which abuts against the impaction face 108 to locate the key within the shaped entrance. As such, when the rotation tool is twisted, the shaped key thereof engages the keyed entrance 109 to rotate the implant.
The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required in order to practise the invention. Thus, the foregoing descriptions of specific embodiments of the invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed as obviously many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the following claims and their equivalents define the scope of the invention.
The term “approximately” or similar as used herein should be construed as being within 10% of the value stated unless otherwise indicated.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020903641 | Oct 2020 | AU | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/AU2021/051175 | 10/8/2021 | WO |
