Background technology
Have the history of decades by the mode operative treatment deformity of spine of internal fixation of spine technology; Adopt the internal fixation of spine technology so far the eighties in 20th century from China, from initial Harrington (Ha Shi rod) technology to the Luque vertebral plate of the seventies under fixation with steel wire, arrive again the CD internal fixation system, the internal fixation of spine technology has obtained very large progress.In recent years, along with the development of spinal biomechanics research and material science, to such an extent as to the internal fixation of spine technology is widely applied in the operative treatments such as spinal column degenerative disease, tumor of spine, wound Spondylitis.
The apparatus of internal fixation of spine utilization comprises pedicle nail and rod.Pedicle nail comprises nail seat and rivet nut, and in the implantable spinal column of rivet nut, nail seat is provided with U-shaped groove, and rod can be inserted in the U-shaped groove of pedicle nail nail seat.When carrying out the internal fixation of spine technology, select first suitable pedicle nail, the rivet nut of pedicle nail is implanted in the spinal column; Recycle suitable rod, it is inserted in the nail seat of pedicle nail in the U-shaped groove, carry out again curved rod, revolve rod, strut, the operation such as pressurization, realize backbone correcting is resetted.After operation, lose in order to prevent from resetting, by arrange in nail seat suitable screw thread and with the locking nut of threaded engagement, make rod and pedicle nail keep fixing.
The normal pedicle nail that uses mainly contains two kinds in the prior art, and a kind of is the fixed angle pedicle nail, and another kind is the multiaxis pedicle nail.
Please refer to Fig. 1, Fig. 1 is the structural representation of fixed angle pedicle nail in the prior art.
As shown in FIG., the fixed angle pedicle nail comprises nail seat and rivet nut, and the two is fixed as an overall structure; The rivet nut bottom has threaded area 3, and nail seat top is provided be used to the U-lag 1 that holds rod, and the sidewall along groove above U-lag 1 is provided with screw thread 2, and this screw thread 2 cooperates and rod can be locked with suitable locking nut.In operation process, implant pedicle nail and carry out orthopedic reset wait operation the time, the position maintenance of rivet nut and nail seat is relative fixing.
The multiaxis pedicle nail comprises nail seat and rivet nut, and nail seat is provided with the female thread that cooperates for locking nut, and is same, and nail seat top is provided be used to the U-shaped groove that holds rod.The bottom of nail seat adopts the ball-joint structure to be connected with the top of rivet nut; With respect to nail seat, rivet nut can be at a plurality of direction rotations, and therefore, the multiaxis pedicle nail also is Universal vertebra arch root screw.
In operation process, implanting and carrying out the pressure bar operation has certain requirement to the rivet nut of pedicle nail and the motility of nail seat, and will prevent from resetting losing after operation, then requires the nail seat of pedicle nail and rivet nut to keep relative stability.
Lose although the fixed angle pedicle nail can reduce postoperative resetting, when carrying out operation process, owing to keep fixing between the nail seat of fixed angle pedicle nail and the rivet nut, can not relatively rotate; When implanting rivet nut, require very strict to each steps such as the selection of entry point and nail road preparations; When revolving the operation of rod, curved rod, in order smoothly rod to be implanted and moulding physiological curve to the patient, often need to cooperate a large amount of apparatuses, thereby cause pedicle nail implant and reset operation very difficult.
Because the rivet nut of multiaxis pedicle nail and nail seat can be rotated in that a plurality of directions are relative, and be more convenient in implantation and reset operation process; But because can not fixed-direction and angle, nail seat also can be rotated on perpendicular to the direction of spine axis relatively with rivet nut, and then causes easily to reset afterwards in operation and lose.
Therefore, providing a kind of respective flexibility that has in operation process, can reduce the pedicle nail that resets and lose after operation, is the technical problem of the required solution of those skilled in the art.
Summary of the invention
Therefore, the purpose of this invention is to provide a kind of pedicle nail, this pedicle nail not only has respective flexibility in operation process, can also reduce to reset after operation and lose.
For achieving the above object, pedicle nail provided by the invention comprises rivet nut and nail seat, and the top of described rivet nut has column, and the shape of cross section of this column is that radian is greater than or equal to the first arc of 180 degree; The bottom of described nail seat is provided with cavity volume, and what the shape of cross section of this cavity volume was radian greater than 180 degree is second arc; The outer peripheral face of described column cooperates with the rotation of the internal face of described cavity, and the under shed that the threaded area of the bottom of described rivet nut is passed described cavity volume stretches out, and described rivet nut is positioned at the diameter of described lower opening less than the width of described under shed.
Optionally, the axis of described column is mutually vertical with the axis of described threaded area.
Optionally, the first arc radian of described column is 180 degree, and the distance between the described column both ends of the surface is greater than the largest contours diameter of described threaded area.
Optionally, an end opening of described cavity volume.
Optionally, the equal opening in the two ends of described cavity volume.
Optionally, also comprise snap ring, on the inwall of an end of the opening of described cavity volume annular groove is set, described snap ring matches with annular groove, and the end face of described snap ring and the end face of described column are inconsistent.
Optionally, the axis direction along described column sets gradually some described annular grooves on the inwall of an end of the opening of described cavity volume.
Optionally, the both sides of the under shed of described cavity volume have the holding tank corresponding with the bottom of described rivet nut.
Optionally, a side of the under shed of described cavity volume has the holding tank corresponding with described rivet nut bottom.
Optionally, the top of described column is provided with nail nail hole, and the top of described cavity volume is provided with the through hole corresponding with described nail nail hole.
Pedicle nail provided by the invention comprises rivet nut and nail seat, and the top of described rivet nut has column, and the shape of cross section of this column is that radian is greater than or equal to the first arc of 180 degree; The bottom of described nail seat is provided with cavity volume, and what the shape of cross section of this cavity volume was radian greater than 180 degree is second arc, and described first arc and the described second arc radius equates; Described column is arranged in described cavity, and the under shed that the threaded area of the bottom of described rivet nut is passed described cavity volume stretches out, and described rivet nut is positioned at the diameter of described lower opening less than the width of described under shed.Above-mentioned pedicle nail is simple in structure, and the first arc and second of the cavity volume cross section the arc radius of column cross section equates to realize that column and cavity volume are rotatable cooperates; Rivet nut is positioned at the diameter of cavity volume lower opening less than the width of cavity volume under shed, and rotating with respect to nail seat for rivet nut provides the space.Adopt said structure, cavity volume cooperates with column can make rivet nut with respect to the axis rotation of nail seat around column, in the process of operation, can regulate easily the position relationship between nail seat and the rivet nut like this, the dress rod for the implantation rivet nut and after implanting facilitates with operations such as revolving rod; After operation, because rivet nut can only be with respect to the axis rotation of nail seat around column, on other directions of space, rivet nut can keep relative fixing with nail seat, can prevent from a predetermined direction resetting like this and lose, reduce on the whole the appearance of the postoperative loss situation that resets.The radian of the maximum radial cross section of column is greater than or equal to 180 degree, can avoid rivet nut with respect to the nail seat translation; The radian of the radial cross-section of the maximum of cavity volume can provide prerequisite with respect to the suitable angle of nail seat rotation for rivet nut greater than 180 degree.
A kind of preferred embodiment in, the first arc radian be 180 the degree, the distance between the column both ends of the surface is greater than the largest contours diameter of threaded area; The column that is about to rivet nut top is set to semicylinder, and the length of column is greater than the maximum gauge of threaded area.This structure can make things convenient for the processing of rivet nut when reaching the object of the invention, make the processing technique of pedicle nail simpler.
In another preferred embodiment, the under shed both sides of cavity volume arrange the holding tank corresponding with the rivet nut bottom.Holding tank can match with the shape of rivet nut, terminates in the holding tank when rivet nut is rotated, and then can increase rivet nut with respect to the rotating range of nail seat, increases the angle between two extreme positions of rivet nut, improves the motility of corresponding operating in the operation process.
The specific embodiment
Core of the present invention provides a kind of pedicle nail, and this pedicle nail not only has respective flexibility in operation process, can also reduce to reset after operation and lose.
In order to make those skilled in the art person understand better the present invention program, the present invention is described in further detail below in conjunction with the drawings and specific embodiments.
Please be simultaneously in conjunction with Fig. 3 and Fig. 4, with reference to figure 2, Fig. 2 is the structural representation of a kind of specific embodiment of pedicle nail provided by the present invention, and Fig. 3 is the structural representation of the rivet nut of pedicle nail shown in Figure 2, and Fig. 4 is the structural representation of the nail seat of pedicle nail shown in Figure 2.
Pedicle nail provided by the present invention comprises rivet nut 5 and nail seat 4.
The top of rivet nut 5 has column 51, and the shape of cross section of column 51 is first arc, and the first arch roof forms cylindrical surface, and the first arc radian can equal 180 degree, also can be greater than 180 degree; The bottom of rivet nut 5 is threaded area 52.In the optimal technical scheme, when the axis of the axis of column 51 and threaded area 52 is mutual vertical, also can form sharp angle between both axis.
The bottom of nail seat 4 is provided with cavity volume 41, and the cross section of cavity volume 41 also is cylindrical surface, and second arc greater than 180 degree of the radian that forms.Nail seat 4 tops are provided with U-shaped groove, and the bearing of trend of U-shaped groove is vertical with the centrage of the Cylinder Surface that cavity volume 41 internal faces form.In addition, same as the prior art, on the U-shaped groove sidewall corresponding female thread 44 can be set, this female thread 44 can match with suitable locking nut.
Please refer to Fig. 5, Fig. 5 is the scheme of installation of pedicle nail duty provided by the present invention.Column 51 is arranged in cavity volume 41, the structure that the first arc radius and the second arc radius are set to equate, the outer peripheral face of column 51 is cooperated with the internal face of cavity 41 is rotatable, rivet nut 5 can be rotated with respect to the axis of nail seat 4 around column 51.The under shed that the threaded area 52 of rivet nut 5 bottoms is passed cavity volume 41 stretches out (take Fig. 5 as reference) downwards.Rivet nut 5 is positioned at the diameter of lower opening of cavity volume 41 less than the width a of under shed; Have corresponding gap like this between the under shed of rivet nut 5 and cavity volume 41, this gap can provide condition with respect to the rotation of nail seat 4 for rivet nut 5; With respect to nail seat 4, rivet nut 5 can be rotated by the axis around column 51 in suitable scope.
In order to make column 51 and nail seat 4 keep linking to each other, the shape of cross section of cavity volume 41 be set to radian greater than 180 spend second arc, can avoid like this rivet nut 5 to separate with nail seat 4 diametrically; The purpose that the first arc radian of column 51 is not less than 180 degree is, makes rivet nut 5 can not carry out translation with respect to nail seat 4.Further, the first arc radian can on radial section, make more subcylindrical of column 51 greater than 180 degree, and such structure can increase the reliability that rivet nut 5 is connected with nail seat 4.
When utilizing above-mentioned pedicle nail operation; Before operation, diameter, the length of the pedicle nail that select to be fit to as required, enter to follow closely angle etc., then enter selection and the preparation of nail road of nail point, implant again above-mentioned pedicle nail.Compare with the pedicle nail of fixed angle, adopt above-mentioned pedicle nail, when implanting the rivet nut of this pedicle nail, can regulate nail seat 4 with respect to the angle of rivet nut 5 according to the operation needs, make things convenient for the implantation of pedicle nail; Compare with the multiaxis pedicle nail, after operation, because rivet nut 5 only can be around the axis rotation of column 51, in the other direction, rivet nut 5 can not be rotated with respect to nail seat 4, thereby can reduce the generation that resets and lose.
As shown in Figure 3, this specific embodiment, the distance between column 51 columns 51 both ends of the surface can greater than threaded area 52 largest contours diameters, make the length of column 51 greater than the maximum gauge of threaded area 52.Make between column 51 both ends of the surface and the threaded area 52 to have stand out, can utilize like this this stand out that rivet nut 5 is connected with nail seat 4.Rivet nut 5 can be the combination of semicylinder and threaded area 52, so that each several part is processed respectively; Also can be structure as a whole.Add respectively man-hour, can also be provided for specially in column 51 and threaded area 52 junctions the recessed cross section that is connected with threaded area 52, to make things convenient for being fixedly connected with of column 51 and threaded area 52.In the optimal technical scheme, the shape of cross section of column 51 is that radian is greater than or equal to the first arc of 180 degree, and making column 51 is a semicylinder, can make things convenient for like this processing of rivet nut 5, reduces the processing cost of pedicle nail.
The cavity volume 41 of nail seat 4 bottoms can be the structure of an end opening; The column 51 that can make things convenient for like this rivet nut 5 inserts and is installed in the cavity volume 41 from the end face of opening.Certainly, also can make cavity volume 41 be the structure of both ends open, with from arbitrary end all can be packed column 51 into cavity 41.When cavity volume 41 1 end openings or the equal opening in two ends, column 51 can link to each other by the snap ring location with cavity volume 41.Please refer to Fig. 5, Fig. 5 is in the pedicle nail provided by the present invention, the structural representation of snap ring.As shown in FIG., snap ring 6 is for having the circulus of opening.The inwall of one end of cavity volume 41 openings arranges annular groove 42; During installation, under shed that can be by cavity 41 is packed snap ring 6 in the annular groove 42, and snap ring 6 matches with annular groove 42; When snap ring 6 cooperated with annular groove, the part of snap ring 6 was exposed in the cavity 41, and the end face of the end face of its exposed portions serve and column 51 is inconsistent, slided with respect to nail seat 4 at the axis direction of column 51 to stop rivet nut 5.By the annular groove 42 that snap ring 6 is set and matches with it, can make rivet nut 5 keep relative fixing with nail seat 4 at column 51 axial directions.In addition, in order to increase the stability of location, also can suitable groove be set in the position that column 51 matches with snap ring 6, perhaps directly utilize the chamfering of column 51 to cooperate 6 pairs of columns 51 of snap ring to position.When cavity volume 41 when only an end is set to hatch frame, the structure that its other end can be set to seal.
In addition, can also adopt other modes to realize the position of rivet nut 5 and nail seat 4 at column 51 axis directions; Such as: can column 51 be located by the mode that lock pin is set, also can adopt positioning sleeve with column 51 location, make positioning sleeve and nail seat 4 fixing, and positioning sleeve is stretched in the cavity 41, inconsistent with the end face of column 51.
According to foregoing description, those skilled in the art can also be on the inwall of an end of cavity volume 41 openings successively the axis direction along column 51 set gradually several annular grooves 42; Like this, different according to the distance between column 51 both ends of the surface of rivet nut 5, select suitable annular groove 42 to cooperate with snap ring, nail seat 4 is matched from different rivet nut 5, same nail seat 4 can be connected with the rivet nut 5 of different model, increase the scope of application and the adaptability of pedicle nail nail seat 4.
Certainly, for the scope of the rotational angle that increases pedicle nail, can improve in the structure of pedicle nail.
Wherein preferred improved procedure is the side setting holding tank 43 corresponding with rivet nut 5 bottoms at the under shed of cavity volume 41.When holding tank 43 is set, during rivet nut 5 rotation, can make holding tank 43 admit the threaded area of rivet nut 5, when rivet nut 5 rotates to extreme position, can be by 43 pairs of rivet nuts of holding tank, 5 location.Similarly, the corresponding holding tank 43 in bottom with rivet nut 5 can also be set in the both sides of the under shed of cavity volume 41, holding tank 43 is set in both sides can further increase rivet nut 5 with respect to the rotating range of nail seat 4, improves the operating flexibility of pedicle nail.
The concrete shape of above-mentioned holding tank 43 can specifically be determined according to the structure of column 51 or threaded area 52; Such as: can be set to curved surface groove as shown in Figure 4, the holding tank 43 of the concrete structures such as V-type groove, elliptical slot also can be set, as long as holding tank 43 is corresponding with rivet nut 5, can hold rivet nut 5, for rivet nut 5 provides corresponding space with respect to nail seat 4 rotations, and increase the rotational angle of rivet nut 5, just can realize increasing the purpose of pedicle nail motility.Select the size of suitable holding tank 43, rivet nut 5 is rotated in preset range, the rotating range of rivet nut 5 is controlled in the rational scope, avoid rivet nut 5 rotating ranges too small, operation technique is inconvenient, and rotating range is excessive, reduces easily the stability of pedicle nail.
As shown in Figure 3 and Figure 4, nail nail hole 53 can also be set at the top of column 51; Corresponding with nail nail hole 53, be provided with through hole 45 at the top of cavity volume 41.The purpose of nail nail hole 53 and through hole 45 is: when operation, suitable shaft can be inserted in the nail nail hole 53 by through hole 45, so that position and the direction of control rivet nut 5 facilitate the carrying out of convenient operation for implanting pedicle nail.
The below is specifically described installation site and the specific works state of pedicle nail provided by the present invention.
Please refer to Fig. 7 and Fig. 8, Fig. 7 is that the rivet nut of pedicle nail provided by the present invention is rotated the sketch map of diverse location with respect to nail seat, and Fig. 8 is the position view that the nail seat of pedicle nail provided by the present invention is rotated with respect to rivet nut.
After implanting pedicle nail, the used rod 8 of operation is installed in the U-shaped groove of nail seat 4, make rod 8 pass across the U-shaped groove of nail seat 4; Female thread 44 on the U-shaped groove sidewall on locking nut 7 and the nail seat 4 is matched, rod 8 and nail seat 4 are fixed together.
When carrying out the orthopedic operation that resets, then revolve rod, pressure bar or other operations with revolving excellent instrument or pressure bar instrument.Usually these operations hocket and realize orthopedic resetting.If the pedicle nail nail seat can not be rotated with respect to rivet nut, then the plasticity of rod 8 there is very high requirement, just can reach the accuracy of operation; And adopting pedicle nail provided by the present invention can adjust by adjusting rivet nut 5 and the position relationship between the nail seat 4 angle of rod 8 and pedicle nail, this just can be providing great convenience of performing the operation, and can guarantee the accuracy of performing the operation.
As shown in Figure 7, the rivet nut 5 of pedicle nail can be rotated with respect to nail seat 4 between A and two positions of C, position shown in the B is that rivet nut 5 is in conplane state with nail seat 4, and the position shown in A and the C is rivet nut 5 rotates to limit state around column 51 axis with respect to nail seat 4 position.But the concrete rotation amplitude of rivet nut 5 also depends on the fit structure of cavity volume 41 and column 51; When holding tank 43 is set, also depend on holding tank 43 concrete sizes.
Certainly, the angle of nail seat 4 also can be adjusted; As shown in Figure 8, nail seat 4 can be rotated certain limit along cylindrical surface with respect to rivet nut 5, the space multiaxis can not occur and rotate; In the other direction, can make like this rivet nut 5 keep relative fixing with nail seat 4.
More than pedicle nail provided by the present invention is described in detail.Used specific case herein principle of the present invention and embodiment are set forth, the explanation of above embodiment just is used for helping to understand method of the present invention and core concept thereof.Should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention, can also carry out some improvement and modification to the present invention, these improvement and modification also fall in the protection domain of claim of the present invention.