CN115105182A - Dynamic triangular support intramedullary nail system for thighbone - Google Patents
Dynamic triangular support intramedullary nail system for thighbone Download PDFInfo
- Publication number
- CN115105182A CN115105182A CN202110309881.5A CN202110309881A CN115105182A CN 115105182 A CN115105182 A CN 115105182A CN 202110309881 A CN202110309881 A CN 202110309881A CN 115105182 A CN115105182 A CN 115105182A
- Authority
- CN
- China
- Prior art keywords
- nail
- tension screw
- screw
- rod part
- femoral
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
- A61B17/74—Devices for the head or neck or trochanter of the femur
- A61B17/742—Devices for the head or neck or trochanter of the femur having one or more longitudinal elements oriented along or parallel to the axis of the neck
- A61B17/744—Devices for the head or neck or trochanter of the femur having one or more longitudinal elements oriented along or parallel to the axis of the neck the longitudinal elements coupled to an intramedullary nail
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
- A61B17/72—Intramedullary pins, nails or other devices
- A61B17/7233—Intramedullary pins, nails or other devices with special means of locking the nail to the bone
- A61B17/725—Intramedullary pins, nails or other devices with special means of locking the nail to the bone with locking pins or screws of special form
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
- A61B17/84—Fasteners therefor or fasteners being internal fixation devices
- A61B17/86—Pins or screws or threaded wires; nuts therefor
- A61B17/8625—Shanks, i.e. parts contacting bone tissue
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
- A61B17/84—Fasteners therefor or fasteners being internal fixation devices
- A61B17/86—Pins or screws or threaded wires; nuts therefor
- A61B2017/8655—Pins or screws or threaded wires; nuts therefor with special features for locking in the bone
Landscapes
- Health & Medical Sciences (AREA)
- Orthopedic Medicine & Surgery (AREA)
- Surgery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Heart & Thoracic Surgery (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Neurology (AREA)
- Medical Informatics (AREA)
- Molecular Biology (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Surgical Instruments (AREA)
Abstract
The invention discloses a dynamic triangular support intramedullary nail system for a femur, which belongs to the technical field of orthopedic implants and comprises a main nail, a diagonal tension screw and a transverse tension screw, wherein the transverse tension screw comprises a first rod part positioned at the tail part and a second rod part positioned at the head part, and the diameter of the first rod part is larger than that of the second rod part. Because the stress concentration of the dynamic femoral triangular support intramedullary nail system is mainly transverse tension screws, the transverse tension screws are designed for different diameters (diameter-variable structures), and the diameter of the first rod part is thicker, so that the transverse tension screws can be prevented from being broken off in use; the second rod part is matched with a screw hole of the diagonal tension screw, the diameter of the second rod part is thin, the diameter of the screw hole matched with the second rod part can be reduced, and the diagonal tension screw is prevented from being broken due to the fact that the screw hole is too thin. Therefore, the invention can better avoid the fracture of the inclined tension screw and the transverse tension screw.
Description
Technical Field
The invention relates to the technical field of orthopedic implants, in particular to a dynamic triangular support intramedullary nail system for a femur.
Background
The proximal intramedullary nail of femur is mainly used for intertrochanteric fracture and high trochanteric fracture of femur. The traditional Proximal femoral intramedullary nail fixation mainly takes a Proximal femoral intramedullary nail (PFN), a novel Proximal femoral internal fixation system (PFNA), a TFNA (femoral bone marrow internal fixation) system of Shandong Weigao orthopedics and the like as main components, wherein the PFNA is a new improved PFN system and is suitable for various types of femoral intertrochanteric fractures, femoral subtrochanteric fractures, femoral neck base portion fractures, femoral neck fractures with femoral shaft fractures, femoral intertrochanteric fractures with femoral shaft fractures and the like.
In recent years, a triangular support intramedullary nail design has emerged, as shown in fig. 1, which includes a main nail 1 'for implanting in the femoral medullary cavity, a diagonal tension screw 2' passing through the upper portion of the main nail 1 ', and a lateral tension screw 3' passing through the top of the main nail 1 'and the diagonal tension screw 2', which has the advantage that the fulcrum is moved inward, and the pressure can be distributed on the diagonal tension screw 2 'and the lateral tension screw 3'. In the research process, the inventor finds that in the existing design of the triangular support intramedullary nail, the main nail, the inclined nail (the inclined tension screw 2 ') and the transverse nail (the transverse tension screw 3 ') are matched with each other, so that the stress is concentrated on the transverse nail (the transverse tension screw 3 ') after the stress is applied, and the transverse nail is broken.
Disclosure of Invention
The invention aims to provide a dynamic femoral triangular support intramedullary nail system which avoids fracture of a transverse nail as much as possible.
In order to solve the technical problems, the invention provides the following technical scheme:
the utility model provides a thighbone developments triangular support intramedullary nail system, includes main nail, oblique tension screw and horizontal tension screw, horizontal tension screw is including the first pole portion that is located the afterbody and the second pole portion that is located the head, the diameter of first pole portion is greater than the diameter of second pole portion.
Further, the junction of the first rod part and the second rod part is a transition inclined plane, and the inclination angle of the transition inclined plane is 30-60 degrees.
Furthermore, a platform and a nail hole are arranged on the oblique tension screw, the nail hole is used for accommodating the transverse tension screw, and the platform is located on the nail hole and close to one side of the main nail along the upper edge.
Furthermore, the depth of the platform does not exceed the lowest point of the upper edge of a screw hole for accommodating a transverse tension screw on the inclined tension screw.
Further, the ratio of the length of the first rod part to the length of the second rod part is 1:1 to 2:1, and/or the ratio of the diameter of the first rod part to the diameter of the second rod part is 4:1 to 4: 3.
Further, the nail hole that is used for holding horizontal tension screw on the oblique tension screw includes two at least holes, two at least holes are followed oblique tension screw axial arrangement and handing-over setting, and the handing-over position forms protrudingly, two at least holes with horizontal tension screw clearance fit, protruding with horizontal tension screw interference fit.
Furthermore, the interference magnitude of the protrusions is 0.1 mm-1 mm, and/or the inclined tension screws are provided with 3 handing-over holes for accommodating the transverse tension screws.
Further, oblique tension screw includes the nail body and is located the tail cap of nail body tail end, the diameter of tail cap is greater than the diameter of the nail body, be used for installing oblique tension screw on the main nail hole 21 be equipped with the terminal surface matched with step of tail cap, the diametric (al) of step is no longer than be used for installing oblique tension screw's the central line in nail hole.
Furthermore, the tail end of the tail cap is an inclined plane, and an included angle between the inclined plane and the axis of the diagonal tension screw is 30-70 degrees.
Furthermore, the bolt body and the tail cap of the diagonal tension bolt are provided with a positioning mechanism on the opposite end faces.
The invention has the following beneficial effects:
according to the dynamic femoral triangular support intramedullary nail system, the transverse tension screw comprises a first rod part positioned at the tail part and a second rod part positioned at the head part, and the diameter of the first rod part is larger than that of the second rod part; because the stress concentration of the product is mainly transverse tension screws, the transverse tension screws are designed to have different diameters (diameter-variable structures), and the diameter of the first rod part is thicker, so that the transverse tension screws can be prevented from being broken off in use; the second rod part is matched with a screw hole of the diagonal tension screw, the diameter of the second rod part is thin, the diameter of the screw hole matched with the second rod part can be reduced, and the diagonal tension screw is prevented from being broken due to the fact that the screw hole is too thin. Therefore, the invention can better avoid the fracture of the inclined tension screw and the transverse tension screw.
Drawings
FIG. 1 is a schematic structural view of a prior art triangular support intramedullary nail design;
FIG. 2 is a schematic structural diagram of the femoral dynamic triangular support intramedullary nail system of the present invention, additionally showing an enlarged view of the nail hole on the oblique tension screw and an enlarged view of the step on the main nail;
FIG. 3 is a schematic diagram of the combination of a transverse tension screw and a diagonal tension screw of the present invention, wherein an enlarged view of the upper platform of the diagonal tension screw is additionally shown;
FIG. 4 is an exploded view of the diagonal tension screw of FIG. 2;
fig. 5 is a schematic view of the whole structure of the tension-stayed screw in fig. 2, wherein (a) is a front view and (b) is an a-direction view.
Detailed Description
To make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.
The invention provides a femoral dynamic triangular support intramedullary nail system, which comprises a main nail 1, a diagonal tension screw 2 (an oblique nail for short) and a transverse tension screw 3 (a transverse nail for short), wherein the transverse tension screw 3 comprises a first rod part 31 positioned at the tail part (the left end in the figures 2-3) and a second rod part 32 positioned at the head part (the right end in the figures 2-3), and the diameter D1 of the first rod part 31 is larger than the diameter D2 of the second rod part 32, as shown in figures 2-5.
When the femoral nail is used, firstly, the main nail 1 can be held by a surgical tool, the treated femoral medullary cavity is implanted, then the diagonal tension screws 2 are implanted and pass through the nail holes 11 on the main nail 1 for installing the diagonal tension screws 2, and then the transverse tension screws 3 pass through the nail holes on the main nail 1 for installing the transverse tension screws 3 and the nail holes 21 on the diagonal tension screws 2 far away from the tail (namely, the nail holes 21 at the lowest positions in fig. 2-3 and the nail holes 21 at the leftmost positions in fig. 4).
The femoral dynamic triangular support intramedullary nail system comprises a transverse tension screw 3, a first rod part 31 and a second rod part 32, wherein the first rod part 31 is positioned at the tail part, and the diameter of the second rod part 32 is larger than that of the first rod part 31; because the stress concentration of the product is mainly the transverse tension screw 3, and the stress concentration position is as the marked point A in the figure, the transverse tension screw 3 is designed to have different diameters (diameter-variable structure), the diameter of the first rod part 31 is thicker, and the transverse tension screw 3 can be prevented from being broken off in use; the second rod part 32 is matched with the nail hole 21 of the inclined tension screw 2, the diameter of the second rod part 32 is thin, the diameter of the nail hole 21 matched with the second rod part can be reduced, and the inclined tension screw 2 is prevented from being broken due to the fact that the position of the nail hole 21 is too thin. Therefore, the invention can better avoid the fracture of the inclined tension screw 2 and the transverse tension screw 3. The invention is mainly used for intramedullary fixation of proximal femur fracture in surgical operation.
In order to improve the strength of the reducing position of the transverse tension screw 3, the junction of the first rod part 31 and the second rod part 32 can be a transition inclined plane 33, in addition, the transition inclined plane 33 can be positioned at the nail hole 21 which is used for accommodating the transverse tension screw 3 on the inclined tension screw 2 in use, a platform 26 matched with the transition inclined plane 33 can be arranged on the inclined tension screw 2, and the platform 26 can be positioned on one side, close to the main nail 1, of the nail hole 21. The upper edge of the nail hole 21 refers to the side of the nail hole facing upward when the nail hole is installed for use. The platform 26 may be formed by milling flat. After the first rod part 31 is thickened, the weak position of the transverse tension screw 3 is located at the junction of the first rod part 31 and the second rod part 32, and pressure acts on the right end of the transverse tension screw 3, so that the length of the first rod part 31 is prolonged as much as possible, the moment arm at the junction of the first rod part 31 and the second rod part 32 can be shortened, the transverse tension screw 3 is firmer, and the transverse tension screw 3 can be effectively prevented from being broken. Because the device acts in the human body, because of the particularity of the applied main body, the specification size and the like need to be strictly controlled, the change in any place can cause huge influence, and the arrangement of the platform 26 can provide a certain avoiding space for the first rod part 31, the length of the first rod part 31 can be increased to the maximum extent in the limited nail placing space, so that the length of the first rod part 31 can be effectively and properly prolonged, the pressure resistance of the transverse tension screw 3 can be increased, the change of the transverse tension screw 3 and even the size of the whole intramedullary nail system can not be caused, and the pressure resistance of the transverse tension screw 3 can be increased on the basis of not influencing other performances of the whole product.
The depth of the platform 26 is preferably not more than the lowest point of the upper edge of the nail hole 21 of the diagonal tension screw 2 for accommodating the transverse tension screw 3, so that the strength of the nail hole 21 of the diagonal tension screw 2 is not weakened, and the length of the first rod part 31 matched with the platform can be prolonged as much as possible, so that the transverse tension screw 3 is firmer.
Optionally, the first rod part 31 passes through a nail hole of the main nail 1 for installing the main nail, or the hole of the main nail 1 for installing the nail hole of the transverse tension screw 3 is completely located on the first rod part 31, so as to ensure that the stress concentration point a is located on the first rod part 31 with the thicker diameter of the transverse tension screw 3, thereby increasing the strength of the transverse tension screw 3. In the limited nail placing space, the length of the first rod part 31 can be effectively increased through the arrangement of the platform 26, so that the first rod part 31 is ensured to completely penetrate through the nail hole of the main nail 1 for installing the main nail.
It can be understood that the platform 26 and the transition inclined plane 33 may not directly contact each other at the initial stage of installation according to actual requirements, a certain gap may be left between the two, or the two may just overlap each other, and the platform 26 may not cause too large reverse acting force to the transition inclined plane 33 in the later stage of activity, so as to prevent the transverse lag screw 3 from backing up.
Alternatively, the angle of inclination of the transition slope 33 may be 30-60 degrees. Specifically, the angle may be 30 degrees, 45 degrees or 60 degrees. Within this range, the contact between the transition slope and the platform 26 is more sufficient, and the contact area is relatively larger, so that the lifting effect of the diagonal tension screws 2 on the transverse tension screws 3 can be properly increased, and the pressure resistance of the whole intramedullary nail system can be increased.
Considering the strength requirement of the transverse tension screw 3 and the size of the space of the femoral nail, the ratio of the lengths of the first rod part 31 to the second rod part 32 is preferably 1:1 to 2:1, and the ratio of the diameters of the first rod part 31 to the second rod part 32 is preferably 4:1 to 4: 3. By defining the length and diameter between the first and second shaft portions 31 and 32, the strength of the lateral tension screw 3 can be sufficiently ensured in a limited femoral nail insertion space. In practical applications, different ratio ranges can be selected according to different specifications, for example, the ratio of the lengths of first rod part 31 and second rod part 32 can be 1:1, 1.5:1, 2:1, etc., and the ratio of the diameters can be 4:1, 2:1, 4:3, etc.
The first rod portion 31 and the second rod portion 32 may be integrally connected or detachably connected.
Further, the screw hole 21 of the diagonal tension screw 2 for accommodating the transverse tension screw 3 may include at least two holes, the at least two holes are arranged along the axial direction of the diagonal tension screw 2 and are arranged in a cross-connection manner, a protrusion 22 is formed at the cross-connection position, the at least two holes are in clearance fit with the transverse tension screw 3, and the protrusion 22 is in interference fit with the transverse tension screw 3, so that the screw hole 21 is in clearance fit with the transverse tension screw 3 to ensure that the transverse tension screw 3 can pass through the screw hole 21; the bulge 22 is in interference fit with the transverse tension screw 3, so that the transverse tension screw 3 can support the diagonal tension screw 2 to bear certain pressure conducted downwards by the diagonal tension screw 2, and meanwhile, the bulge 22 and the transverse tension screw 3 are in interference fit, so that the nail withdrawing phenomenon caused by the diagonal tension screw 2 after operation can be effectively relieved; when the pressure of the diagonal tension screw 2 on the transverse tension screw 3 is too large, the transverse tension screw 3 slides through the bulge 22 in the groove (namely the screw hole 21) of the diagonal tension screw 2 and is transited from one hole to the other hole, so that the pressure is reduced through position transition, the bearing pressure is reduced, the transverse screw can be better prevented from being broken, and the dynamic support is realized.
The factors such as stress are comprehensively considered, the interference magnitude of the bulge 22 is preferably 0.1-1 mm, and the interference magnitude can be adjusted according to the specification of the screw. In the embodiment shown in the figure, the bolt hole 21 for accommodating the transverse tension bolt 3 on the diagonal tension bolt 2 is 3 holes arranged in a cross way. It should be understood that the implementer can appropriately adjust the number of the intersecting holes according to different requirements, and appropriately increase or decrease the number of the intersecting holes as long as the technical problem to be solved by the embodiment of the invention can be achieved.
The inventor discovers in the research process that when the fracture line M is located in the femoral neck, the oblique tension screws penetrate through the fracture line M to connect the femoral head and the femoral shaft together, the oblique tension screws need to be pulled backwards at the tail end through an instrument to pressurize the fracture line M by the conventional oblique tension screws, but the oblique tension screws rebound when the instrument is removed, and the fracture line M is at a position where the fracture line M risks to be opened again. If direct tail cap at the tail end of oblique tension screw adds, the tail cap of oblique tension screw can all bulge main nail because it is fixed through the rotation to draw tension screw and main nail to one side, can cause like this to draw tension screw tail cap and main nail point contact, and fixed fastness is poor. To solve this problem, the present invention preferably adopts the following structural form here:
as shown in fig. 2-5, the oblique tension screw 2 may include a screw body 23 and a tail cap 24 at the tail end of the screw body 23, the diameter of the tail cap 24 is greater than the diameter of the screw body 23, a step 12 matched with the end surface of the tail cap 24 is disposed in the screw hole 11 for mounting the oblique tension screw 2 on the main screw 1, so that the end surface of the tail cap 24 abuts against the step 12 and is in surface contact, which is firmer than point contact, at this time, the oblique tension screw 2 is continuously screwed by an instrument, the head (right end in the figure) of the oblique tension screw 2 can tighten the femoral head to pressurize the fracture line M, and when the instrument is removed, the oblique tension screw 2 cannot rotate reversely, so that there is no risk of re-opening the fracture line M. In the main nail 1, the nail hole 11 is arranged to weaken the strength of the main nail 11 at the position, and the thickness of the main nail 1 corresponding to the position of the center line of the nail hole 11 is the lowest, and the strength is also the lowest, therefore, in order to ensure the strength of the main nail 1, the diameter direction of the step 12 is preferably not more than the center line of the nail hole 11. Therefore, the thickness of the main nail 1 corresponding to the central line position of the nail hole 11 is prevented from being reduced due to the arrangement of the step 12, and the strength of the main nail 1 is effectively ensured.
The intramedullary nail operation requires that the tail cap end of the diagonal tension screw is flush with the outer side of the femoral shaft, and if the oblique tension screw penetrates into the femoral shaft, the oblique tension screw grows into the bone in the fracture healing process, so that the screw is difficult to take; if it leaks out of the femoral shaft, its outer slope may damage the collateral muscles. To avoid this problem, the tail end of the tail cap 24 is preferably an inclined surface 241, and an included angle α between the inclined surface 241 and the axis of the diagonal tension screw 2 is preferably 30-70 degrees, and specifically may be 30 degrees, 45 degrees, 50 degrees, 70 degrees, and the like, so as to match the inclination angle of the femoral shaft.
In order to select the tail cap 24 with a suitable length according to the diameter of the femoral shaft of different people and enable the tail cap to be flush with the outer side of the femoral shaft, the tail cap 24 can be designed as a separate tail cap, and can be detachably connected to the nail body 23 of the diagonal tension screw 2 through the fixing nail 25, and the specific structure of the fixing nail 25 for fixing the tail cap 24 on the nail body 23 can adopt a conventional structure in the field, and is not described herein again.
In order to fix the orientation of the tail cap 24, the end faces of the body 23 of the tension bolt 2 opposite to the tail cap 24 may be provided with a positioning mechanism, and the positioning mechanism may be provided in various manners as will occur to those skilled in the art, for example, one of the positioning mechanism is provided with a groove, and the other one is provided with a boss matching with the groove. In the embodiment shown in the figures, the locating mechanism includes a groove 242 on the end face of the tail cap 24 and a boss 231 on the shank 23 that mates with the groove 242.
The dynamic triangular support intramedullary nail system for the femur of the embodiment of the invention shown in the drawings can be used in the operation with reference to the following steps:
as shown in fig. 2-3, the screw thread at the top end of the main nail 1 is held by a special surgical tool and inserted into the prepared femoral medullary cavity. The inclined tension screw 2 is implanted to penetrate through the nail hole of the main nail 1 until the tail cap 24 (playing a depth limiting role due to larger diameter) is tightly clamped at the left side position of the main nail 1. In operation, the left end of the inclined tension screw 2 is required to be flush with the bone surface after being implanted into the femur. Too deep implantation causes bone growth into the inner hole at the tail end in the fracture healing process, and difficulty in taking out; the left end of the implant is too shallow and leaks out of the bone surface, causing tissue friction and muscle damage. Because the thickness of thighbone of different people is different, the partial length of the limit for depth of the tail end of the oblique tension screw of every length all can have different specifications, oblique nail tail cap 24 and oblique tension screw 2 split type design, tail cap 24 tail end is fluted 242, and oblique tension screw 2 nail body 23 tail end has complex boss 231 with it, guarantees that the tail end implants back inclined plane 241 direction and bone face parallel and level. Meanwhile, the depth of the inclined tension screw 2 can be freely selected according to the measured thickness of the femoral shaft, and the specification of the inclined tension screw 2 can be reduced. After the oblique tension screw 2 is implanted, the tail cap 24 is locked by using the fixing nail 25.
Thereafter, the cross pin 3 is implanted. A transverse nail 3 with a proper length is selected to be implanted, a first rod part 31 of the transverse nail 3 penetrates through a transverse hole in a main nail 1, a second rod part 32 penetrates through a lower nail hole 21 which is positioned on an inclined tension screw 2 and is closest to the left cortex bone of the femur, and the joint position of the first rod part 31 and the second rod part 32 is close to the platform 26 of the inclined nail 2. At the moment, the main nail 1, the transverse nail 3 and the inclined nail 2 form a triangular supporting structure, and the internal stress reaches a stable and uniform distribution state. Human weight presses on the femoral head after operation, the femoral head acts on the cross pin 3 through the oblique tension screw 2, the moment arm from the femoral head to the junction position of the first rod part 31 and the second rod part 32 on the cross pin 3 is smaller than the moment arm from the femoral head to the junction position of the cross pin 3 and the main pin 1, the diameter of the first rod part 31 is thickened, and the length of the first rod part 31 is prolonged, so that the strength of the cross pin 3 is higher. When the pressure on the inclined nail 1 is further increased, the position of the second rod part 32 on the transverse nail 3 passes through the lowest cross hole and gradually enters the upper cross hole, and the fracture of the transverse nail 3 due to excessive bearing force is avoided by further compressing the fracture line M to share a part of the pressure.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. A dynamic femoral triangular support intramedullary nail system comprises a main nail, a diagonal tension screw and a transverse tension screw, and is characterized in that the transverse tension screw comprises a first rod part positioned at the tail part and a second rod part positioned at the head part, and the diameter of the first rod part is larger than that of the second rod part.
2. The femoral dynamic triangular support intramedullary nail system according to claim 1, wherein the junction of the first and second rod portions is a transition bevel, and the inclination angle of the transition bevel is 30-60 degrees.
3. The femoral dynamic triangular support intramedullary nail system according to claim 2, wherein the oblique tension screw is provided with a platform and a nail hole for accommodating the transverse tension screw, and the platform is located on one side of the nail hole close to the main nail.
4. The femoral dynamic triangularly supported intramedullary nail system of claim 3, wherein a depth of said platform does not exceed a lowest point of an upper edge of a nail hole in said diagonal tension screw for receiving a lateral tension screw.
5. The femoral dynamic triangular support intramedullary nail system of claim 1, wherein the ratio of the length of the first rod portion to the second rod portion is 1:1 to 2:1 and/or the ratio of the diameter of the first rod portion to the second rod portion is 4:1 to 4: 3.
6. The femoral dynamic triangular support intramedullary nail system according to one of claims 1 to 5, wherein the nail holes for accommodating the lateral tension screws on the oblique tension screws comprise at least two holes, the at least two holes are axially arranged along the oblique tension screws and are arranged in a cross-connection manner, a protrusion is formed at the cross-connection position, the at least two holes are in clearance fit with the lateral tension screws, and the protrusion is in interference fit with the lateral tension screws.
7. The femoral dynamic triangular support intramedullary nail system according to claim 6, wherein the interference of the protrusion is 0.1mm to 1mm, and/or the screw holes of the oblique tension screws for accommodating the transverse tension screws are 3 holes arranged in a cross-over manner.
8. The dynamic femoral triangular support intramedullary nail system according to any one of claims 1 to 5, wherein the oblique tension screws comprise a nail body and a tail cap at the tail end of the nail body, the diameter of the tail cap is larger than that of the nail body, a step matched with the end surface of the tail cap is arranged in a nail hole for installing the oblique tension screws on the main nail, and the diameter direction of the step does not exceed the center line of the nail hole for installing the oblique tension screws.
9. The femoral dynamic triangular support intramedullary nail system according to claim 8, wherein the tail end of the tail cap is a bevel, and the bevel forms an angle of 30-70 degrees with the axis of the oblique tension screw.
10. The femoral dynamic triangular support intramedullary nail system according to claim 8, wherein a positioning mechanism is provided on the opposite end surfaces of the nail body and the tail cap of the oblique tension screw.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110309881.5A CN115105182A (en) | 2021-03-23 | 2021-03-23 | Dynamic triangular support intramedullary nail system for thighbone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110309881.5A CN115105182A (en) | 2021-03-23 | 2021-03-23 | Dynamic triangular support intramedullary nail system for thighbone |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115105182A true CN115105182A (en) | 2022-09-27 |
Family
ID=83324141
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110309881.5A Pending CN115105182A (en) | 2021-03-23 | 2021-03-23 | Dynamic triangular support intramedullary nail system for thighbone |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115105182A (en) |
-
2021
- 2021-03-23 CN CN202110309881.5A patent/CN115105182A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6562042B2 (en) | Orthopedic implant used to repair intertrochanteric fractures and a method for inserting the same | |
| AU2005304439B2 (en) | Endosteal nail | |
| US4950270A (en) | Cannulated self-tapping bone screw | |
| US7666207B2 (en) | Fixation device for bones | |
| US7918853B2 (en) | Orthopaedic plate and screw assembly | |
| TW200408367A (en) | Bone screw | |
| US8758345B2 (en) | Interlocking nail geometry and method of use | |
| CN217793288U (en) | Femoral reverse triangular support intramedullary nail | |
| CN115105182A (en) | Dynamic triangular support intramedullary nail system for thighbone | |
| CN103654934B (en) | For blade plate combined locking screw and comprise its bone plate system | |
| CN211534741U (en) | Internal fixing device for limb fracture | |
| CN215384529U (en) | Femoral intramedullary nail fixing system | |
| CN219289653U (en) | Proximal femur combined internal fixing device | |
| CN216876560U (en) | Fixed triangular support intramedullary nail for femoral screw hole | |
| CN217566270U (en) | Femoral neck triangular locking and fixing system | |
| CN220655655U (en) | Assembled intramedullary nail plate system for treating proximal femur fracture | |
| CN215129915U (en) | Steel plate supporting fracture fixing system | |
| CN213787728U (en) | Tail cap for intramedullary nail system and intramedullary nail system thereof | |
| CN113729903B (en) | Femoral intramedullary nail fixation system | |
| CN220588338U (en) | PFNA system with self-sustaining locking tail cap | |
| CN216394227U (en) | Internal fixing system for intertrochanteric fracture of femur | |
| CN219782704U (en) | Dynamic hybrid intramedullary fixation device for treating ankle fusion | |
| CN215129900U (en) | Double anti-rotation interlocking system for femoral neck | |
| CN220404098U (en) | Femoral neck sliding locking system | |
| CN220124794U (en) | Reinforced medical screw expansion sleeve |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |