Patent Application
20230149059
The present teachings relate to intramedullary (IM) fixation. More particularly, the present teachings relate to an implant and a method for implanting an implant in a medullary canal in performing intramedullary fixation.
Surgical procedures to repair bone fractures can include the use of implants, such as plate fixation, IM nails, and interfragmentary screws, that are commonly associated with complications such as infection, wound breakdown, nonunion, implant failures, poor cosmetic outcome, and local numbness, etc. The term “intramedullary” means that the nail resides at least partly in the medullary canal of a bone. IM fixation involves the treatment of unstable fractures with an intramedullary nail as a treatment option for bone fractures and other injuries. Generally, intramedullary fixation devices for bone fractures are complicated by the need to perform reliable fixation of the bone while providing some flexibility supporting anchoring and/or improving fixation of the device. Additionally, “interfragmentary” screws are used to provide compression between the fracture fragments to stabilize the fracture.
In one example, U.S. Pat. No. 7,625,395 to Helmut Muckter (“Muckter”) discloses an interfragmentary screw that is required to be implemented in separate pieces during implantation. For example, Muckter discloses that a threaded part with a bone thread must be screwed into the bone utilizing a cannulated wrench that is pushed over a wire cable before a hexagon socket head nut is subsequently attached with a metal thread. Additionally, Muckter’s interfragmentary screw may not be utilizable in procedures that require minimizing bone compression.
Improvements in IM fixation are therefore desired.
During the preparation and placement of existing intramedullary nails and associated syndesmotic fixation, there is the potential for the placement of those syndesmotic members be overly rigid and inflexible, complicating the healing process and introducing instability to the fixation members. Additionally, some known syndesmotic members can be configured in a way that introduces undesirable bone compression in certain injuries. This is solved in the presently disclosed embodiments by providing a surgical nail that limits bone compression yet imparts flexibility to an implant and therefore the healing bone, according to some embodiments.
According to embodiments, a surgical nail can include a nail body having a proximal end, an elongate intermediate portion comprising an intermediate flexible portion, and a distal end. In some embodiments, the proximal end and the distal end are coupled and offset from one another by the elongate intermediate portion. The intermediate flexible portion can include two or more cables that are bonded together (e.g., by welding, adhesive bonding, fusing, and/or the like) to maintain a fixed length.
According to some embodiments, the cable can include two or more cables twisted around one another in a helical arrangement and bonded together. In some embodiments, the proximal portion can include a threaded proximal portion coupled to the threaded portion by the intermediate flexible portion. According to some embodiments, the distal end portion can include a threaded end portion.
According to some embodiments, the proximal portion can include a threaded proximal portion coupled to the threaded end portion by the intermediate flexible portion. In some embodiments, the proximal end portion can include a cylinder having an outer surface defining a perimeter of the surgical nail.
According to some embodiments, the one or more cables is configured in one or more arrangements consisting of a Helical Hollow Strand (HHS) arrangement, and/or a simple stranded cable arrangement. In some embodiments, the proximal portion and the threaded end portion are coupled together by the intermediate flexible portion as a unitary, integrated element prior to any use of the surgical nail in an implant procedure. According to some embodiments, the cylinder can include at least one through holes for receiving a fixation element configured to anchor the surgical nail into a bone fragment.
According to some embodiments, the intermediate flexible portion is configured to permit the proximal portion to bend at an angle relative to the distal portion such that a health practitioner is enabled to implant the surgical nail in a medullary canal as a unitary, integrated element. Also, in some embodiments, the intermediate flexible portion is configured to be flexible when implanted in the medullary canal and is further configured to minimize bone compression.
A method for performing implantation of a surgical nail during a surgical procedure to repair a fracture of a bone is described. According to some embodiments the method can include identifying a starting point of a medullary canal of a patient’s bone; providing an opening in the bone using a surgical device; inserting the surgical nail as a unitary element into the medullary canal; driving the surgical nail through a first bone fragment via a portion of the medullary canal; and fixing the intramedullary canal to a second bone fragment, where the intramedullary nail is be flexibly fixed to the bone first and second bone fragments and is configured to minimize compression of the bone. The intermediate flexible portion can be configured to be flexible when implanted in the medullary canal and is further configured to minimize bone compression.
Embodiments may be implemented in hardware, firmware, software, or any combination thereof. Intramedullary fixation can be performed utilizing surgical nails, such as intramedullary nails, to facilitate the healing of fractured bones. However, rigid intramedullary nails that do not sufficiently flex can impede anchoring to bone fractures and aggravate the healing process. Further, conventional intramedullary nails having some degree of flexibility may compress and cause additional complications. The embodiments shown in the exemplary methods and devices are not exhaustive and other operations can be performed in addition to the illustrated processes. In some embodiments of the present disclosure, the operations may vary and/or can be performed in a different order.
According to some embodiments, intermediate flexible portion 116 is configured to be bendable throughout its length. According to some embodiments, intermediate flexible portion 116 is configured to resist compression. In this regard, these embodiments differ substantially from concepts related to interfragmentary screws that may be configured to achieve compression. For example, in the embodiment illustrated in
In some embodiments, intermediate flexible portion 116 can comprise two or more cables 116a and 116b bonded together. For example, two or more cables 116a and 116b can be twisted and bonded together in a helical arrangement. In other embodiments, two or more cables 116a and 116b can be welded together in a braided arrangement.
In some non-limiting examples, cable 116 can be a single or multi-layered Helical Hollow Strand (HHS) tube. In another example, cable 116 can be a simple stranded cable arranged in various n×m cable classifications, where n represents the number of strands in a cable and m represents the number of wires in each strand (e.g., 1×19, 1×7, 7×19, etc.). In some examples, cable 116 can be a multi-layered multi-directional cable. Additionally, cable 116 can be solid or cannulated.
In one non-limiting example, the component bodies such as proximal end 110, intermediate flexible portion 116, and distal end 120, can be bonded together (e.g., by welding, adhesive bonding, or otherwise joining) at a fixed length prior to the point of use. In this integrated implementation, surgical nail 100 is configured to be inserted in a medullary canal as a unitary structure, not to be inserted as independent component bodies as in prior art devices. According to some embodiments, the intermediate flexible portion is configured to permit the proximal end to bend at an angle relative to the distal end such that the health practitioner is enabled to implant the surgical nail in a medullary canal as a unitary, integrated element. For example, surgical nail 100 can be joined stably by bonding each component to another, such that the whole assembly rotates as one.
According to some embodiments, proximal end 110 includes one or more threaded portions. As shown, for example, proximal end 110 can include first proximal threaded portion 111 and second proximal threaded portion 112. Also, as shown, distal end 120 of surgical nail 100 can include threaded end portion 118. Each of the threaded portions 111, 112, and 118 can be configured having cutting threads capable of being driven into one or more bone fragments. For example, threaded end portion 118 can be driven, for example, by a driving device (as described hereinbelow) such that threaded end portion 118 is fixed into a bone fragment. Likewise, threaded proximal portion 111 and threaded intermediate portion 112 can be driven to fix the cutting threads into corresponding portions of a bone fragment proximal to an opening lumen in the bone. Also, according to some embodiments (not shown) a surgical nail can be configured to perform proximal or distal end fixation, e.g., by an anchoring element.
As above, intermediate flexible portion 216 is configured to be bendable throughout its length. According to some embodiments, intermediate flexible portion 216 is configured to resist compression. In this regard, these embodiments differ substantially from concepts related to interfragmentary screws that may be configured to achieve compression. In one example, cables 216a and 216b can be formed of any flexible material, such as metal and/or metal alloy material in some embodiments. For example, cables 216a and 216b can be formed of steel, iron, aluminum, copper, nickel, any other suitable metal material, fiber, metal-fiber, polymer, and/or any other flexible material. Cables 216a and 216b can be welded (or otherwise bonded) to one another to avoid unraveling and to improve stability of the cables. Additionally, as described above, bonding cables 216a and 216b configures intermediate flexible portion 216 to resist compression.
According to some embodiments, proximal end 210 includes one or more threaded portions. As shown, for example, proximal end 210 can include first proximal threaded portion 211 and second proximal threaded portion 212. According to some embodiments, distal end 220 can include threaded end portion 218.
According to additional embodiments, surgical nail 200 can include a cylindrical body portion 214 and at least one through hole 213 for receiving a fixation element configured to anchor the surgical nail into a bone fragment (not shown). Cylindrical body portion 214 defines an outer perimeter of surgical nail 200 and is disposed having at least one through hole 213 entering one side of the surgical nail outer perimeter and exiting through the other side of the outer perimeter. In this manner, surgical nail 200 is configured to accept transverse screws for fixation of surgical nail 200 to one or more bone fractures.
In some embodiments, intermediate flexible portion 216 comprises two or more cables 216a and 216b bonded together. For example, cables 216a and 216b can be twisted and bonded together in a helical arrangement. In other embodiments, cables 216a and 216b can be bonded together in a braided arrangement.
In some non-limiting examples, cable 216 can be a single or multi-layered HHS tube, or a simple stranded cable arranged in various n×m cable classifications, where n represents the number of strands in a cable and m represents the number of wires in each strand as described in detail above, a multi-layered multi-directional cable, and/or any other arrangement of a cable. Additionally, cable 216 can be solid or cannulated.
As noted above, surgical nail 200 can include one or more threaded portions, such as threaded proximal portion 211, threaded intermediate portion 212 and threaded end portion 218. Each of the threaded portions, 211, 212, and 218 can be configured using cutting threads to be driven into one or more bone fragments. For example, following insertion through a medullary canal, threaded end portion 218 can be driven by a driving device (as discussed hereinbelow) such that threaded end portion 218 is fixed into a bone fragment. Likewise, threaded proximal portion 211 and threaded intermediate portion 212 can be driven to fix the cutting threads into corresponding portions of a bone fragment proximal to an opening lumen in the bone.
According to some embodiments, the intermediate flexible portion 316 is configured to be bendable throughout its length. As above, intermediate flexible portion 316 is configured to resist compression as opposed to interfragmentary screws that may be configured to achieve compression.
According to some embodiments, surgical nail 300 can include a cylindrical body portion 314 and at least one through hole 313 for receiving a fixation element configured to anchor the surgical nail into a bone fragment. For example, after implantation of surgical nail in a surgical procedure, a health practitioner can drive one or more screws into through holes 313 to fix and anchor a first fragment of the bone to surgical nail 300, such that it is retained sufficiently to heal together with a second fragment of the bone.
As above, intermediate flexible portion 316 is flexible and configured by two or more cables 316a and 316b to be bendable without producing compression. By permitting flexibility without compression, intermediate flexible portion 316 allows the surgical nail to stay stably fixed to each bone fragment minimizing risks of nonunion or aggravation to the healing process. Cables 316a and 316b can be formed of any flexible material, such as one or more metal and/or metal alloy material. Cables 316a and 316b can be bonded (such as by welding, adhesives, or any other suitable bonding process or device) one cable to another to another to avoid unraveling and to improve stability of the cables. In some embodiments, a ratio of length lc of cylindrical body portion 314 to length li of flexible intermediate portion 316 may be large relative to a corresponding ratio in the embodiment of
As described in detail above, cable 316 can be a single or multi-layered HHS tube, or a simple stranded cable arranged in various n×m cable classifications, where n represents the number of strands in a cable and m represents the number of wires in each strand, a multi-layered multi-directional cable, and/or any other arrangement of a cable. Additionally, cable 316 can be solid or cannulated.
According to some embodiments, proximal end 410 can include a drive socket 411 to receive and engage a driver of an implement useful to insert surgical nail 400 into a medullary canal. For example, drive socket 411 of intramedullary nail 400 may include a Hexalobe opening therein that can be rotated by a driver inserted therein to cause intramedullary nail 400 to be inserted as a unitary element into a medullary canal of a bone.
As in the embodiment of
As above, the intermediate flexible portion 416 is flexible and may be configured to bend. According to some embodiments, intermediate flexible portion 416 is configured to resist compression. In this regard, these embodiments differ substantially from concepts related to interfragmentary screws that may be configured to achieve compression. For example, intermediate flexible portion 416 is configured by two or more bonded cables 416a and 416b to resist compression, which is distinct and different Muckter’s interfragmentary screw that is configured to achieve bone compression.
In some embodiments, intermediate flexible portion 416 can comprise two or more cables 416a and 416b bonded together. For example, cables 416a and 416b can be twisted and bonded together in a helical arrangement. In other embodiments, cables 416a and 416b can be bonded together in a braided arrangement.
According to additional embodiments, surgical nail 400 can include a cylindrical body portion 414 and at least one through hole 413 for receiving a fixation element configured to anchor the surgical nail into a bone fragment (not shown).
In some non-limiting examples, cable 416 can be a single or multi-layered HHS tube, a simple stranded cable arranged in various n×m cable classifications, as described above. In some examples, cable 416 can be a multi-layered multi-directional cable. Additionally, cable 416 can be solid or cannulated.
In one non-limiting example, as shown in
Referring to
A surgical nail 400 is discussed for illustration, although any method 700 can be implemented using any embodiment of a surgical nail (e.g., 100, 200, 300, 400). According to some embodiments, a reamer or other suitable device can be used to access a lumen of the bone. For example, a patient may be prepared for surgery, including placing the patient under general anesthesia or sedation, administering antibiotics, and placing the patient on an operating room table. A radiographic/fluoroscopic imaging device can be directed toward the site of the procedure. According to some embodiments, reaming can be performed.
Procedure 700 continues with operation 710, in which the health practitioner can insert the surgical nail 400 into the medullary canal of a first bone fragment, where the surgical nail is inserted as a unitary element. In other words, the surgical nail is disposed such that the proximal end 410 and distal end 420 are integrated together by the intermediate flexible portion 416 prior to use/insertion into the medullary canal. According to some embodiments, the intermediate flexible portion is configured to permit the proximal end to bend at an angle relative to the distal end such that the health practitioner is enabled to implant the surgical nail in a medullary canal as a unitary, integrated element.
Procedure 700 continues with operation 715, in which the health practitioner can driver the intramedullary nail through a bone fracture via a portion of the medullary canal. According to some embodiments, the unitary surgical nail 400 is inserted utilizing a driving device, such as driving device 500.
Procedure 700 continues with operation 720, where the health practitioner fixes the surgical nail to a second bone fragment. In some examples, a threaded end portion 418 is driven utilizing driving device 500 into the second bone fragment. In an embodiment, syndesmotic fixation members can be placed, for example, in through holes 413 to minimize enable the bone fragments to join efficiently having some degree of flexibility while minimizing compression of the bone.
The present invention has been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.
The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present invention. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.
The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments but should be defined only in accordance with the following claims and their equivalents.
