Patent Application
20120303067
Fractured fragments of a bone may be brought together using, for example, surgical forceps. Currently, surgical forceps include a pair of jaws that pivot around a central hinged joint such that it is often difficult to achieve proper compression of the fragments. In addition, a combination of multiple devices must be used to compress the fragments, hold the compressed fragments in a desired position relative to one another and to guide drills, bone fixation elements and other tools through one or more holes of a bone plate positioned along the fractured bone to permanently fix the fragments in position.
The present invention relates to a device for compressing fractured portions of a bone, comprising first and second jaws movable relative to one another to compress fractured portions of a bone therebetween, the first and second jaws being connected to one another such that bone gripping portions thereof remain parallel to one another throughout a permitted range of motion of the first and second jaws and a first guide sleeve attached to the distal end of the first jaw and a second guide sleeve attached to the distal end of the second jaw, the first and second guide sleeves having central axes coaxial with one another.
The present invention may be further understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The present invention relates to a device for treating fractures and, in particular, to a device for compressing portions of a fractured bone. Exemplary embodiments of the present invention describe a device including a pair of parallel jaws configured to compress fractured portions of a bone such as, for example, an end of the humerus forming the elbow joint. In addition, the parallel jaws of the device maintain a desired compression of the fractured portions of bone and provide a guide for drilling a hole into a bone at an angle desired for insertion of a bone fixation element. Although the exemplary embodiments specifically describe a fractured end of a humerus, it will be understood by those of skill in the art that the device may be used to compress fractured portions of any of a variety of bones. It should be noted that the terms “proximal” and “distal” as used herein with reference to the device, are intended to refer to a direction toward (proximal) and away from (distal) a user of the device.
As shown in
The device 100 may further include one or more variable angle tips 112, as shown in
Each of the handles 102a, 102b, as shown in
The jaws 104a, 104b are placed over fractured portions of a bone and moved toward one another to compress the bone therebetween to draw the fractured portions of bone into a desired spatial relation to one another. Once the portions of the bone have been compressed to the desired relation, this desired compression is maintained via the locking mechanism 110 which holds the jaws 104a, 104b in the desired position relative to one another. The locking mechanism 110 includes a longitudinal rod 144 and a nut 152 longitudinally movable therealong. The rod 144 extends longitudinally from a first end 146 to a second end 148. The first end 146 is pivotably attached to the first handle 102a at a position proximal of the connecting portion 118a. The second end 148 includes a stop 153 extending radially outward therefrom to prevent the nut 152 from becoming disengaged from the rod 144. The second handle 102b includes an elongated opening 150 extending along a length thereof, sized and shaped to slidably accommodate the rod 144. The elongated opening 150 permits the rod 144 to be longitudinally and laterally moved therein as the handles 102a, 102b are moved toward and away from one another.
The nut 152 is movable between the stop 153 at the second end 148 of the rod 144 and the elongated opening 150 in the second handle 102b from an unlocked position to a locked position. The nut 152 may be longitudinally moved along the rod 144 via, for example, spinning engagement of an external threading along a length of the rod 144 and a corresponding internal threading along an interior of the nut 152. In the unlocked position, the nut 152 is positioned adjacent the stop 153 such that the handles 102a, 102b are movable relative to one another. As the handles 102a, 102b are moved relative to one another, the rod 144 slides through the elongate opening 150. Once sufficient movement of the handles 102a, 102b has been achieved so that the jaws 104a, 104b are in the desired position relative to one another, the device 100 may be locked by moving the nut 152 toward the first end 146 of the rod 144 until the nut abuts the second handle 102b. This prevents the handles 102a, 102b and, consequently, the jaws 104a, 104b from being moved apart from one another. Thus, the bone remains compressed between the jaws 104a, 104b.
The connecting portions 118 of the handles 102a, 102b cross over one another to attach to the jaws 104a, 104b. First and second connecting portions 118a, 118b are pivotably connected to one another via, for example, a pin 142 at the point at which the connecting portions 118a, 118b cross over one another. A proximal end 120a of the first connecting portion 118a of the first handle 102a is connected to a proximal end 126a of a first corresponding connecting portion 124a of a first jaw 104a via a sliding joint 138a while a distal end 122a of the first connecting portion 118a is pivotably coupled to a distal end 128b of a second corresponding connecting portion 124b of a second jaw 104b via a pin 140a. Similarly, a proximal end 120b of the second connecting portion 118b of a second handle 102b may be coupled to a proximal end 126b of the second corresponding connecting portion 124b via a slidable joint 138b while a distal end 122b of the second connecting portion 118b is coupled to a distal end 128a of the first corresponding connecting portion 124a via a pin 140b. The slidable joints 138a, 138b may include, for example, a pin 192 extending from the proximal ends 120a, 120b of the connecting portions 118a, 118b slidably received within an elongated opening 194 extending longitudinally through the proximal ends 126a, 126b of the corresponding connecting portions 124a, 124b. The connection between the connecting portions 118 and the corresponding connecting portions 124 of the handles 102a, 102b and the jaws 104a, 104b via the slidable and pivotable joints 138a, 138b, 140a, 140b, 142 permit movement of the handles 102a, 102b toward and away from one another so that the jaws 104a, 104b toward and away from one another while maintaining the parallel configuration of the jaws 104a, 104b.
The guide sleeves 106a, 106b are attached to the distal ends 116 of the jaws 104a, 104b such that channels 154 extending therethrough have central axes substantially perpendicular to the bone gripping portions 136 of the jaws 104a, 104b and substantially coaxial with one another. Since the jaws 104a, 104b remain parallel through the entire range of motion, the central axes of the guide sleeves 106a, 106b also remain coaxial through the range of motion. The guide sleeves 106a, 106b may also include teeth 156, or other bone engaging structures, along surfaces 158 thereof, which face a bone to be gripped therebetween. Thus, when the device 100 is used to compress fractured portions of bone, the teeth 156 grip the bone, preventing the device 100 from being inadvertently moved out of the desired position. In an alternate embodiment, the device 100 further comprises a spike couplable to one of the guide sleeves 106a, 106b such that a tip of the spike engages the bone and/or an opening of a bone plate positioned over the bone. The spike may, for example, be coupled to the first guide sleeve 106a to engage the bone and/or an opening of a bone plate positioned over the bone while the bone is being drilled via the second guide sleeve 106b.
The variable angle tip 112, as shown in
The body 162 may further include a cap 172, as shown in
In use, fractured portions of a bone are reduced by placing the jaws 104a, 104b over the fractured portions and moving the jaws 104a, 104b toward one another via the handles 102a, 102b to compress the fractured portions of bone therebetween until a desired spatial relationship between the fractured portions has been achieved. If it is desired to maintain the compression of the fractured portions, the jaws 104a, 104 may be locked over the bone by moving the nut 152 of the locking mechanism 110 from the unlocked position along the rod 144 to the locked position. The bone may then be temporarily fixed using, for example, K-wires inserted through the bone via, for example, the guide sleeves 106a, 106b. A bone plate may be positioned over the fractured portions of the bone and engaged by one of the jaws 104a, 104b, while the other jaw contacts an opposite surface of one of the fractured portions of bone to reduce the fracture as desired. One or more holes may then be drilled into the portions of bone through holes in the bone plate guided by the guide sleeves 106a, 106b so that the plate may be fixed to the fractured portions bone by inserting one or more bone fixation elements through the plate holes as would be understood by those skilled in the art. Once the fractured portions of the bone have been fixed in the desired position, the device 100 may be removed from the bone. Although the exemplary surgical technique only describes one bone plate, it will be understood by those of skill in the art that the bone may be fixed using more than one bone plate.
If the bone plate includes variable angle holes, a user may couple a variable angle tip 112 to the one of the first and second guide sleeves 106a, 106b which is to engage the bone plate. The above process is repeated with the hole being drilled through the variable angle hole and into the portions of bone at an angle relative to the axis of the variable angle hole which is within the permitted range of angulation for the hole. As would be understood by those skilled in the art, where two bone plates are being fixed the opposite sides of the fractured portions of bone, it may be desirable to couple a variable angle tip 112 to each of the guide sleeves 106a, 106b. As described above, the variable angle tip 112 is coupled to the guide sleeve 106a, 106b by inserting the drill sleeve 160 into the channel 154 such that, in the operative position, the body 162 faces the bone. The drill sleeve 160 is inserted substantially coaxially along the central axis of the guide sleeve 106a, 106b. The second end 186 of the tip portion 174 of the variable angle tip 112 is then inserted into a variable angle hole of the bone plate such that a central axis of the tip portion 174 is substantially coaxial with a central axis of the variable angle hole. The device 100 is then closed over the bone (i.e., jaws 104a, 104b are moved toward one another such that both the jaws 104a, 104b contact the bone). As the jaws 104a, 104b are closed, the body 162 of the variable angle tip 112 pivots relative to the drill sleeve 160, defining an angle of insertion of a bone fixation element to be inserted through the variable angle hole. In particular, the angle of insertion is determined by the central axis of the drill sleeve 160 relative to the central axis of the tip portion 174. Thus, a guide wire and/or drill tip inserted through the variable angle tip 112, coaxially with the drill sleeve 160 is angled within a predetermined range of angulation relative to the tip portion 174 such that a hole may be drilled into the bone at the desired angle of insertion relative to the central axis of the bone plate.
In a further embodiment, the device 100 further comprises drill guides which may be coupled to the guide sleeves 106a, 106b to facilitate drilling of the bone coaxial to central axes of the guide sleeves 106a, 106b. The drill guides is shaped so that it is insertable through the guide sleeves 106a, 106b (e.g., cylindrical) and includes a lumen extending therethrough such that a drill tip and/or guide wire may be inserted therethrough coaxially with the central axes of the guide sleeves 106a, 106b. In addition, the drill guide may be available in a variety of different sizes (e.g., varying diameters of the lumen) to accommodate drill tips and/or guide wires of various sizes).
As shown in
The handles 202a, 202b may further including springs 230, biasing the handles apart from one another. Thus, a user may simply release the pressure on the handles 202a, 202b to allow the handles 202a, 202b to move apart from one another. In an alternative embodiment, the handles 202a, 202b are substantially similar to the handles 102a, 102b of the device 100, including finger loops at proximal ends 214 thereof which permit a user to draw the handles away from one another using their fingers. The handles 202a, 202b may also include a locking mechanism 210, substantially similar to the locking mechanism 110 of the device 100. Similarly, the locking mechanism 210 includes a rod 244 extending from a first end 246 pivotable attached to the first handle 202a and slidably attached to the second handle 202b. A nut 252 may be used to lock the handles 202a, 202b relative to one another (e.g., prevent the handles 202a, 202b and jaws 204a, 204b from moving farther apart from one another) such that the jaws 204a, 204b may maintain a compression of fractured bone held therebetween. It will be understood by those of skill in the art that the device 200 may be used in a manner substantially similar to the exemplary technique as described above with respect to the device 100.
It will be apparent to those of skill in the art that various modifications and variations can be made in the structure and the methodology of the present invention, without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of the appended claims and their equivalents.
