CN205411398U

CN205411398U - Reduce stress shielding's hip joint prosthesis structure

Info

Publication number: CN205411398U
Application number: CN201521031177.4U
Authority: CN
Inventors: 郭同彤; 赵唐雷
Original assignee: Shenzhen Graduate School Harbin Institute of Technology
Current assignee: Shenzhen Graduate School Harbin Institute of Technology
Priority date: 2015-12-11
Filing date: 2015-12-11
Publication date: 2016-08-03
Anticipated expiration: 2025-12-11

Abstract

The utility model provides a reduce stress shielding's hip joint prosthesis structure, it includes false body handle main part, false body handle main part surface is equipped with the plasma coating layer, false body handle main part includes upper segment X and hypomere Y, and upper segment X is 65 with hypomere Y's comparing of length: 79, the error is 3%, is transition region between upper segment X and the hypomere Y, and transition region is level and smooth, has a chamfer, the chamfer is the contained angle of transition face and vertical direction, and the sine value of chamfer is tan0.125, and the error is 3%. The utility model discloses femoral stem prosthesis, handle body length degree is medium, does not have the neck design, and the cross -section is the design of follow -on notch, and proper amount the reduction has increased the area of contact of false body with the bone when cutting the bone. For the zimmerTraper false body, the compact bone substance density regional when the greater trochanter has reduced by 0.2% at this false body of 0.69 - 0.77gcm3 at the stress of femoral near -end, and the average stress on the thighbone has reduced by 3.5%.

Description

A kind of hip prosthesis structure reducing stress shielding

Technical field

This utility model relates to medical instruments field, particularly relates to a kind of hip prosthesis structure reducing stress shielding.

Background technology

The enforcement of replacement of total hip be unable to do without hip stem, and the quality of prosthesis handle has conclusive impact for the success or not of replacement of total hip.A kind of novel applicable collodiaphyseal angle is less, and the longer prosthese of neck of femur is devised, thus obtains extraordinary surgical effect.

Existing femoral hip stem major part is standardized designs, standardized Hip stem design can not meet proprietary needs, such as collodiaphyseal angle is less, the femur type that neck of femur is longer, will result in that osteotomy is unreasonable causes prosthese bad with bony fusion when using standardized prosthese, thus cause prosthetic loosening.

Skeleton can occur bony remodeling after implanting prosthese, and skeletal reconstruction can be affected by external stress, so prosthese will be no longer appropriate for using when stress is concentrated excessive.

In sum, a osteotomy is appropriate, and prosthese primary stability is good, and bone remodelling at a specified future date is good, it is adaptable at greater trochanter, apparent bone density is at 0.69-0.77g/cm³Crowd, about the 8-10% of this kind of Ren Zhan China total population, this product will have the biggest market prospect.

Utility model content

The purpose of this utility model is to provide a prosthesis handle moderate-length, is improvement notch shape without neck design, shank body cross section, prosthesis handle surface uses plasma spraying to process, suitably reduce sclerotin intercepting amount, raising initial stage prosthese stability, it is suitable for little collodiaphyseal angle, the type femoral bone end prosthesis of the longer patient of neck of femur.

nullIn order to solve problem in prior art，This utility model provides a kind of hip prosthesis structure reducing stress shielding，It includes prosthesis handle main body，Prosthesis handle body surfaces is provided with plasma sprayed coating，Described prosthesis handle main body includes epimere X and hypomere Y，The length ratio of epimere X and hypomere Y is 65:79，Error is ± 3%，It it is transitional region between epimere X and hypomere Y，Transitional region smooths，There is a chamfering，Described chamfering is the angle of transition face and vertical direction，The sine value of chamfering is tan0.125，Error is ± 3%，The feature in three cross sections of prosthesis handle main body is as follows，AA cross section is the cross section of prosthesis handle body top，BB cross section is the cross section in the middle part of prosthesis handle body transition region，CC cross section is the cross section of prosthesis handle bottom part body，Three cross sections use of the same race sets up mode，The mode of setting up in cross section: in rectangular coordinate be，Three cross sections are class oval cross section，It is made up of 8 line segments altogether，Four arcs，Two orthodromes and two small arc-shapeds，Four sections of straight lines，Every straight line is the most tangent with two adjacent circular arcs，The ratio of semi-minor axis length in AA cross section is 20.16:12，Error is ± 3%，Orthodrome is 25:4 with the ratio of small arc-shaped radius，Error is ± 3%.

As further improvement of the utility model, a length of 4mm of described transitional region vertical direction, error is ± 3%.

As further improvement of the utility model, the ratio of semi-minor axis length in BB cross section is 19.5:8, and error is ± 3%, and orthodrome is 5:2 with the ratio of small arc-shaped radius, and error is ± 3%.

As further improvement of the utility model, the ratio of semi-minor axis length in CC cross section is 14.33:6.5, and error is ± 3%, and orthodrome is 5:3 with the ratio of small arc-shaped radius, and error is ± 3%.

The beneficial effects of the utility model are:

This utility model type femoral bone end prosthesis, shank body is of moderate length, and without neck design, cross section is follow-on notch design, increases the contact area of prosthese and bone while appropriate minimizing osteotomy.

This utility model prosthese is biconial, in front view, prosthesis handle lower end is conical grip, and with near-end sectional design, segment identifier transitions smooth, this being designed to increases the contact area with proximal femurs, can also reduce the injury to pulp cavity, the stress simultaneously reduced in femoral stem is concentrated, and reduces femoral stem fracture incidence rate.

Relative to Zimmer/Traper prosthese, when the bone density in greater trochanter region reduces 0.2% at this prosthese of 0.69-0.77g/cm3 at the stress of the near-end of femur, and the mean stress on femur reduces 3.5%.

This utility model left view is the taper of gradually transition, so can preferably disperse the power that prosthese produces on femur, make stress distribution uniform.

Accompanying drawing explanation

Fig. 1 is a kind of hip prosthesis structural representation reducing stress shielding of this utility model；

Fig. 2 is the sectional view of Fig. 1；

Fig. 3 A, Fig. 3 B, Fig. 3 C are the AA of Fig. 2, BB, CC sectional view；

Fig. 4, Fig. 5, Fig. 6 are the strain energy comparison diagrams on dual extension-compression modulus femur of prosthese and traditional Z immerM/LTraper prosthese；Fig. 4 is near end of thighbone contrast, and Fig. 5 is distal femur, and Fig. 6 is the maximum stress contrast on femur；

Fig. 7 is the schematic diagram of region chamfering shown in section B-B.

Detailed description of the invention

Below in conjunction with the accompanying drawings this utility model is described further.

This utility model is a kind of near-end anatomical form type femoral bone end prosthesis, the notch tee section design that prosthesis handle is of moderate length, designs without neck, improves, and shank body near-end meets femur anatomical structure, and prosthese just face uses plasma spray coating process to process；The proximate transition in terms of front view of described near-end anatomical form type femoral bone end prosthesis uses stagewise tapered profile, transitional region has a less chamfering, can effectively reduce stress to concentrate and occur and prosthesis handle fractures incidence rate, the strengthening design and can improve the contact area of prosthese and femur of epimere；In terms of left view, the easement curve of prosthese the most smooth prosthesis handle cross section is modified model notch shape, increases the contact area with bone.The applicable different patient of this utility model type femoral bone end prosthesis, can carry out proportional zoom according to the measurement size of patient femur's near-end and select；Meet human femur under loading near-end anatomical structure to greatest extent, it is adaptable at greater trochanter, apparent bone density enables the patient to faster and better recovery human normal motor capacity the patient of 0.69-0.77g/cm3, improves the service life of prosthese.Use this type type femoral bone end prosthesis can improve the motility of operation, shorten operating time, alleviate the misery of sufferer.

Shown in Figure 2, this Novel thighbone handle prosthese, femoral stem shank body (hatched parts) uses plasma spraying to process.

In Fig. 3 A, Fig. 3 B, Fig. 3 C, in Fig. 2 there is a chamfering in region shown in section B-B, and from the beginning of at the upper and lower 2mm of section B-B, this can make the part of upper end, BB cross section keep greater area of contact with bone, it is possible to so that transition region smooths.

The mode of setting up in cross section: three cross sections use of the same race sets up mode, rectangular coordinate is, this is class oval cross section, it is made up of 8 line segments altogether, four arcs, is shown in circular arc S1, S2, S3, the S4 in Fig. 3 A, four sections of straight lines, seeing straight line L1, L2, L3, the L4 in Fig. 3 A, every straight line is the most tangent with two adjacent circular arcs.Figure midpoint M is the central point of class oval cross section, and some P is the midpoint of circular arc S4, and some N is the intersection point of the extended line of straight line L1 and L2, the length of a length of short axle of class oval cross section of line segment MN, the length of a length of class oval cross section major axis of PM.For Fig. 3 B and Fig. 3 C, the distribution with Fig. 3 A is similar, it is simply that size changes.

The ratio of semi-minor axis length in AA cross section is 20.16:5, in figure, orthodrome (S1, S3) is 10:1 with the ratio of small arc-shaped (S2, S4) radius, the ratio of semi-minor axis length in BB cross section is 39:25, in figure, orthodrome is 3:1 with the ratio of small arc-shaped radius, the ratio of semi-minor axis length in CC cross section is 14.33:6.5, in figure, orthodrome is 5:3 with the ratio of small arc-shaped radius, such as Fig. 2, BB cross section is X to the distance of the peak in AA cross section, BB cross section is Y to the distance in CC cross section, and the length ratio of epimere X and hypomere Y is 65:79.So benefit of design: anti-torsion, four arcs design can reduce the stress inside femur and concentrate, reduce bone resorption, and the sine value scheming medium and small chamfering is tan0.125, so the benefit of design: increase the volume of epimere, reduces initial stage deflection.

It show prosthesis handle lower end biconial shank body with reference to Fig. 2.

It show the cross sectional shape at three major section with reference to Fig. 3 A, Fig. 3 B, Fig. 3 C, be modified model notch cross section, AA, BB, CC cross section has different sizes respectively, can select according to different patient's conditions, and do so can improve the contact area of prosthese and femur.

With reference to Fig. 4, Fig. 5, Fig. 6 are the strain energy correlation curves on dual extension-compression modulus femur of prosthese and traditional Z immerM/LTraper prosthese.Fig. 4 is near end of thighbone contrast, and Fig. 5 is distal femur, and Fig. 6 is the maximum stress contrast on femur.In figure, transverse axis is the elastic modelling quantity coefficient on femur, the elastic modelling quantity of former femur be cortical bone be 17000Mpa, spongy bone is 3000Mpa, can change the elastic modelling quantity of femur after being multiplied by coefficient, relative to Zimmer/Traper prosthese, when the bone density in greater trochanter region is at 0.69-0.77g/cm³This prosthese reduces 0.2% at the stress of the near-end of femur, and the mean stress on femur reduces 3.5%.

Above content is to combine concrete preferred implementation further detailed description of the utility model, it is impossible to assert that of the present utility model being embodied as is confined to these explanations.For this utility model person of an ordinary skill in the technical field, without departing from the concept of the premise utility, it is also possible to make some simple deduction or replace, all should be considered as belonging to protection domain of the present utility model.

Claims

null1. the hip prosthesis structure reducing stress shielding，It is characterized in that: it includes prosthesis handle main body，Prosthesis handle body surfaces is provided with plasma sprayed coating，Described prosthesis handle main body includes epimere X and hypomere Y，The length ratio of epimere X and hypomere Y is 65:79，Error is ± 3%，It it is transitional region between epimere X and hypomere Y，Transitional region smooths，There is a chamfering，Described chamfering is the angle of transition face and vertical direction，The sine value of chamfering is tan0.125，Error is ± 3%，The feature in three cross sections of prosthesis handle main body is as follows，AA cross section is the cross section of prosthesis handle body top，BB cross section is the cross section in the middle part of prosthesis handle body transition region，CC cross section is the cross section of prosthesis handle bottom part body，Three cross sections use of the same race sets up mode，The mode of setting up in cross section: in rectangular coordinate be，Three cross sections are class oval cross section，It is made up of 8 line segments altogether，Four arcs，Two orthodromes and two small arc-shapeds，Four sections of straight lines，Every straight line is the most tangent with two adjacent circular arcs，The ratio of semi-minor axis length in AA cross section is 20.16:12，Error is ± 3%，Orthodrome is 25:4 with the ratio of small arc-shaped radius，Error is ± 3%.
A kind of hip prosthesis structure reducing stress shielding the most according to claim 1, it is characterised in that: a length of 4mm of described transitional region vertical direction, error is ± 3%.
A kind of hip prosthesis structure reducing stress shielding the most according to claim 1, it is characterised in that: the ratio of semi-minor axis length in BB cross section is 19.5:8, and error is ± 3%, and orthodrome is 5:2 with the ratio of small arc-shaped radius, and error is ± 3%.
A kind of hip prosthesis structure reducing stress shielding the most according to claim 1, it is characterised in that: the ratio of semi-minor axis length in CC cross section is 14.33:6.5, and error is ± 3%, and orthodrome is 5:3 with the ratio of small arc-shaped radius, and error is ± 3%.