Femoral intramedullary nail with adjustable angleTechnical Field
The invention belongs to the technical field of orthopedic implants, and particularly relates to an angle-adjustable femoral intramedullary nail.
Background
The femoral intramedullary nail is a preferred treatment scheme for femoral intertrochanter combined femoral diaphysis fracture, aiming at the bone difference of patients, the lag screw is divided into a plurality of neck shaft angles for implantation, at present, one main nail cannot be matched with the lag screw with a plurality of neck shaft angles, so that the lag screw implanted in different neck shaft angles needs to be divided into different angle specifications for the main nail to correspond to patients with different requirements and clinical needs, and therefore, a medical instrument production enterprise can stock a large number of main nails with various specifications.
At present, when in operation, a plurality of specifications of main nails are required to be sent to a hospital for selection by doctors, so that stock delivery can be carried out on the multi-neck dry-corner all-specification main nails, the consumption of raw materials is large, the processing period is long, the number of tool specifications required to be prepared is large (occupying a pressing tool stock area), the multi-specification production changing and debugging time is increased, and the risks of defective products generated in debugging are increased. Meanwhile, because the intramedullary nail products have high manufacturing cost and the consumption periods of the main nails with different specifications are different, a large amount of main nails with different specifications are stored, so that backlog cost is high, great challenges are presented to productivity arrangement, and in addition, the main nails with various specifications are required to be circulated, so that cost increase in various aspects is easily caused by one operation stock of the main nails with various specifications. Accordingly, there is a need for an angularly adjustable femoral intramedullary nail to address the above-mentioned problems.
Disclosure of Invention
In view of the above, the invention aims to provide an angle-adjustable femoral intramedullary nail, so that a main nail with one specification can form various different included angles with a lag screw, and can be matched with the needs of patients in clinic in real time so as to achieve the best postoperative effect, and simultaneously, the inventory cost and the turnover cost can be effectively reduced.
In order to achieve the above purpose, the technical scheme of the invention is realized as follows:
An angularly adjustable femoral intramedullary nail, comprising:
the main nail is used for being implanted into a longitudinal marrow cavity of a femur, and is provided with an oblique directional hole;
The guide sleeve assembly comprises a plurality of guide sleeves, the guide sleeves can be arranged in the directional holes in a penetrating mode and fixed in the directional holes, inclined holes are formed in the guide sleeves, and when different guide sleeves are fixed in the directional holes, the included angles between the central lines of the inclined holes and the longitudinal directions of the main nails are different;
And the lag screw is penetrated in the inclined hole, and the center line of the lag screw coincides with the axis of the guide sleeve.
Further, the guide sleeve comprises a tubular main body and a flange, the flange is arranged at one end of the tubular main body, the tubular main body is penetrated in the main nail, the flange is attached to the outer surface of the main nail, a screw hole is formed in the flange, and the flange is locked and fixed on the main nail through a fixing nail penetrating through the screw hole.
Further, the tubular body and the flange are integrally formed.
Further, the outer edge of the orientation hole is provided with a groove, and when the flange is embedded in the groove, the outer surface of the flange does not exceed the surface of the periphery of the groove.
Further, the flange is carved with the angle value of the included angle between the central line of the inclined hole and the longitudinal direction of the main nail.
Further, a first guide pin hole is formed in the longitudinal center of the main pin, a second guide pin hole is formed in the tubular main body, when the guide sleeve is installed in the inclined hole, the center line of the first guide pin hole is coincident with the center line of the second guide pin hole, and the diameter of the first guide pin hole is smaller than or equal to that of the second guide pin hole.
Further, the pull screw is provided with an anti-rotation groove, the main screw is provided with an anti-rotation screw, and the anti-rotation screw can extend into the anti-rotation groove.
Still further, the anti-rotation nail includes a nut threadably coupled within the main nail and extending longitudinally along the main nail and a polish rod.
Further, the anti-rotation groove extends in a strip shape along the length direction of the lag screw.
Further, the main nail comprises a proximal end, a middle section and a distal end, a tail cap is detachably arranged at the proximal end of the main nail, an interlocking hole is formed in the distal end of the main nail along the radial direction, and a locking nail is detachably arranged in the interlocking hole.
The invention has the beneficial effects that:
The angle-adjustable femoral intramedullary nail utilizes the guiding sleeve to guide to replace the main nail to guide the lag screw, and uses a more flexible low-cost accessory guiding sleeve to replace the high-cost main nail. The outer surface dimensions of different guide sleeves are completely consistent, and the guide sleeves are matched with the same main nail, and the included angles between the central lines of the inclined holes of different guide sleeves and the longitudinal direction of the main nail are different. The guide sleeve assembly is formed by different guide sleeves, so that the neck dry angle of a patient is matched, only a group of guide sleeve assemblies, a main nail and a lag screw are needed to be equipped, compared with the original mode of arranging the directional holes with different angles on the main nail, the number of the main nails needed to be prepared in operation is greatly reduced, the stock period is greatly shortened, the site occupation of storage logistics is effectively reduced along with the reduction of the stock quantity of the main nails, and the circulation cost of warehouse in and warehouse out is saved.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention. In the drawings:
FIG. 1 is a schematic view showing the structure of an angle-adjustable femoral intramedullary nail according to an embodiment of the present invention;
FIG. 2 is a partial cross-sectional view of an angularly adjustable femoral intramedullary nail according to an embodiment of the present invention;
FIG. 3 is a cross-sectional view of a staple according to an embodiment of the present invention;
FIG. 4 is a schematic structural view of a guide sleeve according to an embodiment of the present invention;
FIG. 5 is a cross-sectional view of a guide sleeve according to an embodiment of the present invention;
FIG. 6 is a schematic view of a lag screw according to an embodiment of the present invention;
FIG. 7 is a schematic view of an embodiment of the present invention;
Fig. 8 is a schematic view showing the cooperative installation of the lag screw and the guide sleeve according to the embodiment of the present invention.
Reference numerals illustrate:
1. a main nail; 11, a first guide pin hole, 12, a directional hole, 13, a groove, 14 and an interlocking hole;
2. 21, a tubular main body, 22, a flange, 23, an inclined hole, 24, a screw hole, 25 and a second guide pin hole;
3. a lag screw 31, a threaded end 32, a mating end 33, and an anti-rotation groove;
4. tail cap, 5, fixing nail, 6, locking nail;
7. anti-spin nail, 71, screw cap, 72, polish rod.
Detailed Description
The guide pin hole 11 is aligned with a guide pin, and is implanted into the longitudinal intramedullary canal of the femur along the guide pin. The proximal end of the main nail 1 is provided with an inclined directional hole 12, the included angle between the central line of the directional hole 12 and the axis of the first guide pin hole 11 can be 120-130 degrees, and the outer edge of the directional hole 12 is provided with a groove 13.
As shown in fig. 4, the guide sleeve 2 includes a tubular body 21 and a flange 22. The tubular body 21 and the flange 22 are integrally formed, the flange 22 is arranged at one end of the tubular body 21, the tubular body 21 is arranged in the directional hole 12 of the main nail 1 in a penetrating way, and the flange 22 is attached to the outer surface of the main nail 1. Specifically, in this embodiment, when the guide sleeve 2 is mounted in the orientation hole 12, the flange 22 is embedded in the groove 13, and the outer surface of the flange 22 does not exceed the surface of the periphery of the groove 13, so that a smooth transition effect can be achieved, and irritation to soft tissues is effectively reduced.
In the present embodiment, the cross section of the orientation hole 12 is oblong, and the inner wall of the orientation hole 12 and the outer wall of the tubular body 21 are in contact with each other, so that the tubular body 21 of the guide bush 2 is also in an oblong tubular structure.
The flange 22 is provided with screw holes 24, and the flange 22 is locked and fastened to the main nail 1 by the fixing nails 5 penetrating the screw holes 24. In the present embodiment, the screw hole 24 is a counter bore, and when the fixing nail 5 locks the flange 22 to the main nail 1, the head of the fixing nail 5 is sunk into the screw hole 24, so that soft tissue irritation can be reduced.
The tubular main body 21 of the guide sleeve 2 is provided with a second guide pin hole 25, and when the guide sleeve 2 is arranged in the directional hole 12 of the main pin, the center line of the first guide pin hole 11 is overlapped with the center line of the second guide pin hole 25. In particular, the diameter of the second guide pin hole 25 is not smaller than that of the first guide pin hole 11, so that the preset guide pin can smoothly pass through, and the main pin 1 can be conveniently installed.
As shown in fig. 5, the axis of the first guide pin hole 11/the second guide pin hole 25 intersects with the central line of the inclined hole 23 to form an obtuse included angle α, and the flange 22 is carved with an angle value of the included angle α, and the angle value of the included angle α is equal to the angle value of the neck dry angle of the patient.
The neck-drying angle of men was 132 ° on average and the neck-drying angle of women was 127 ° on average. In the present embodiment, the guide sleeve 2 assembly includes three guide sleeves 2 with included angles α of 125 °, 130 °, and 135 °, but is not limited to these three angles. The guide sleeve 2 with a plurality of different angles can be arranged in the guide sleeve 2 assembly according to specific conditions. In this embodiment, the included angle between the center line of the directional hole 12 and the axis of the first guide pin hole 11 is 120 ° -130 °, so that the inclined holes 23 with different inclination angles can be processed inside the guide sleeve 2.
As shown in fig. 6, the lag screw 3 includes a threaded end 31 and a mating end 32, the threaded end 31 being locked in the femoral head, the mating end 32 being disposed through the angled bore 23 of the guide sleeve 2. The threaded end 31 is designed as a conical thread, that is, the outer diameter of the thread of the threaded end 31 is consistent, and the bottom diameter of the thread is gradually increased from the left end to the right end so as to realize compression in operation. The mating end 32 is of a polish rod structure, and the side surface of the mating end 32 is provided with an anti-rotation groove 33.
As shown in fig. 7, the anti-rotation nail 7 includes a nut 71 and a polish rod 72, and the nut 71 is screwed into the main nail 1 and extends longitudinally along the main nail 1. In this embodiment, the nut 71 and the polish rod 72 are integrally formed.
Fig. 8 is a schematic diagram showing the cooperation installation of the lag screw 3 and the guide sleeve 2, wherein the anti-rotation groove 33 is communicated with the second guide pin hole 25 when the lag screw 3 is inserted into the guide sleeve 2. Referring to fig. 2, the lower end of the polish rod 72 of the rotation preventing nail 7 can extend into the rotation preventing groove 33 along the second guide pin hole 25, so that the rotation of the lag screw 3 along the circumferential direction can be effectively avoided. In particular, the anti-rotation groove 33 extends along the length direction of the lag screw 3, providing a certain adjustment space for the implantation depth of the lag screw 3.
The intramedullary nail of the embodiment is implanted by matching a guide sleeve 2 corresponding to a neck stem angle according to clinical needs before operation, installing the guide sleeve in an orientation hole 12 of a main nail 1, fixedly assembling the guide sleeve on the main nail 1 by using a fixed nail 5, implanting the main nail 1 into a femoral intramedullary cavity through a preset guide pin, then implanting a lag screw 3 into a patient through an inclined hole 23 in the guide sleeve 2, screwing a rotation preventing nail 7 into the main nail 1, extending the lower end of the rotation preventing nail into a rotation preventing groove 33, intersecting the lag screw 3 to achieve the rotation preventing function, implanting a lock nail 6 in an interlocking hole 14 at the far end of the main nail 1, and finally assembling a tail cap 4 at the top end of the main nail 1.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.