CN217793473U - Femoral stem system and hip prosthesis system - Google Patents

Abstract

The utility model discloses a thighbone handle system and hip joint prosthesis system belongs to orthopedic implant technical field, thighbone handle system includes the long crescent thighbone handle of a plurality of handles, each the eccentricity of thighbone handle all is located 32mm-49 mm's within range, and a plurality of the variation range less than or equal to 7mm of the neck height of thighbone handle. The utility model discloses but furthest's every crowd's offset and neck height value of recovery to resume hip joint abduction lever arm, make the vast majority of people match well. The utility model provides a selection to real crowd's more suitable offset and the high setting of neck to make the effectual abductor arm of force of recovering of patient and suitable leg length, obtain good postoperative effect.

Description

Femoral stem system and hip prosthesis system

Technical Field

The utility model relates to the technical field of orthopedic implants, in particular to a femoral stem system and a hip joint prosthesis system.

Background

Pain relief and restoration of Hip biomechanics are ideal targets for modern Total Hip Arthroplasty (THA). Reconstruction of Femoral offset/eccentricity (FO) is important to restore the biomechanics of the hip joint, particularly of the abduction lever arm. Proper offset recovery may enhance hip joint motion and reduce the risk of dislocation.

The current clinical total hip replacement has the problem that offset (offset/eccentricity) is not recovered in place, so that the stability of the hip joint, the reaction force of the joint, the polyethylene abrasion and the moving range are influenced. Gait analysis and finite element analysis studies report that a 15% to 20% reduction in FO is associated with a weakness in the abductor mechanism (as shown in figure 1) because of the reduced lever arm, resulting in a change in lameness gait, reducing the extent of shock-free THA motion. In addition, this reduction in offset results in increased knuckle reaction forces exerted on the bearing surfaces and outer race, which negatively impacts THA wear and survival.

It has been found that the human body has an offset range of 30-57mm, but the offset range of the early prosthesis in the market is 36-52.8mm, and because of the limited range of the offset for each model, the offset of the prosthesis is small (as shown in fig. 2 (a)) even if the longest ball is selected, and the offset of the prosthesis is large (as shown in fig. 2 (b)) even if the shortest ball is selected for some patients when matching the prosthesis. The existing prosthesis offset setting cannot meet the requirements of people, the selection of the upper and lower limit ranges of the offset needs to be increased for the size of each femoral stem, and the proposed selection range of the offset needs to be provided for each size of femoral stem because the offset of the femoral stem has certain correlation with the size selection of the stem.

In addition, the problem of unequal leg lengths exists in current clinical total hip replacements, and it has been reported clinically that although there are two options for offset and high offset handles in the current handle, the difference in leg length is up to 56% even when the difference exceeds 11 mm. The leg length difference after hip replacement exceeds 1 cm, which causes claudication, abnormal force transmission of hip joint and revision surgery, and is the main reason of litigation. It has been reported that unequal lower limb length is perceived in 32% of total hip arthroplasty patients. There is a significant correlation between leg length differences and chronic low back pain and hip joint symptoms. Unequal lengths of 20 to 30mm are the critical limits for increasing the physiological load on the lungs, heart and neuromuscular system.

The research shows that the human body self-test femoral neck height range is as follows: 20-37mm, while the stem height of the existing prosthesis is in a higher position in the human body data, which will cause the problem of unequal leg lengths after the replacement of a considerable part of the human (fig. 3). The neck height is related to the femoral stem model setting, so it is also necessary to propose a suggested neck height range for each stem model, i.e. a different neck height range for each model stem.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is to provide an offset and neck height set up thighbone handle system and hip joint prosthesis system that more accords with the human body.

In order to solve the technical problem, the utility model provides a technical scheme as follows:

in one aspect, a femoral stem system is provided, which comprises a plurality of femoral stems with gradually increased stem lengths, wherein the eccentricity of each femoral stem is within the range of 32mm-49mm, and the variation range of the neck heights of the plurality of femoral stems is less than or equal to 7mm.

Further, the neck height is in the range of 23mm-30mm.

Further, the stem lengths of the femoral stems are all in the range of 93mm-153 mm.

Furthermore, the length range of the femoral stem is [93mm,107mm ], the eccentricity of the femoral stem is 32mm-41mm, and the neck height is 23mm-30mm.

Furthermore, the stem length range of the femoral stem is (107mm, 113mm), the eccentricity of the femoral stem is 36mm-43mm, and the neck height is 23mm-30mm.

Furthermore, the length range of the femoral stem is (113mm, 125mm), the eccentricity of the femoral stem is 37mm-49mm, and the neck height is 23mm-30mm.

Furthermore, the handle body of the femoral handle is a rectangular double-taper handle;

or the handle body of the femoral handle is provided with a groove and is a rectangular double-taper handle;

or the handle body of the femoral handle is provided with a groove and a vertical ridge.

In another aspect, a hip joint prosthesis system is provided, comprising a plurality of hip joint prostheses, each hip joint prosthesis comprising a ball head and a femoral stem in the femoral stem system, wherein the ball head is connected with a free end of a neck of the femoral stem.

Further, the eccentricity of the hip joint prosthesis is within the range of 30mm-55mm, and the variation range of the neck heights of the hip joint prosthesis is less than or equal to 17mm.

Further, the neck height of the hip joint prosthesis is in the range of 20mm-37 mm.

The utility model discloses following beneficial effect has:

the utility model discloses a thighbone handle system and hip joint prosthesis system, including the long crescent thighbone handle of a plurality of handles, the eccentricity of each thighbone handle all is located 32mm-49 mm's within range, and the variation range less than or equal to 7mm of the neck height of a plurality of thighbone handles, and the neck height of thighbone handle does not have obvious increase trend along with the increase of prosthesis model size promptly, and the neck height variation range is no longer than 7mm, this be with the obvious difference of current product, current product neck height increases obviously. By the arrangement, the offset and the neck height of each crowd can be recovered to the maximum extent, so that the hip joint abduction lever arm is recovered, and most people can be well matched. The utility model provides a selection to true crowd's more suitable offset and neck height setting to make the effectual abductor arm of force of recovering of patient and suitable leg length, obtain good postoperative effect.

Drawings

Fig. 1 is a prior art illustration of the moment arm of abductor affected by offset, wherein (a) is preoperative, (b) is postoperative, and the arrow in (b) shows the shortening/insufficiency of offset resulting in abductor relaxation;

FIG. 2 is a prior art, more clinically significant case-difference plot of offset, where (a) shows the offset being smaller and (b) shows the offset being larger;

FIG. 3 is a prior art, more widely differing case presentation of neck heights, wherein (a) shows a small neck height and (b) shows a large neck height;

fig. 4 is a schematic structural view of a femoral stem in the femoral stem system of the present invention;

fig. 5 is another schematic structural view of the femoral stem in the femoral stem system of the present invention;

fig. 6 is a schematic view of another structure of the femoral stem system of the present invention;

fig. 7 is a good case-showing diagram of the femoral stem in the femoral stem system according to the present invention, wherein (a) is a structural hip joint prosthesis femoral stem, and (b) is another structural hip joint prosthesis femoral stem;

fig. 8 is a schematic diagram showing different specifications of the prosthetic ball head in the hip joint prosthesis system of the present invention.

Detailed Description

To make the technical problems, technical solutions and advantages of the present invention clearer, the following description is made in conjunction with the accompanying drawings and specific embodiments.

In one aspect, the present invention provides a femoral stem system, as shown in fig. 4-6, including a plurality of stem length increasing femoral stems, the eccentricity (offset, horizontal distance from the center of the femoral head to the axis of the stem body) of each femoral stem is within the range of 32mm-49mm, and the variation range of the neck height (vertical distance from the center of the femoral head to the joint of the femoral stem and the proximal end of the medullary cavity) of the plurality of femoral stems is less than or equal to 7mm, preferably, the neck height is within the range of 23mm-30mm.

The inventor researches and discovers that by setting different offsets and neck heights for different types of prostheses (the types of the prostheses can be divided according to different handle lengths of femoral stems), the offset and neck height values of each crowd can be recovered to the maximum extent, so that the hip abduction lever arm can be recovered, and most people can be well matched, as shown in figure 7.

The utility model discloses a femoral stem system, including the long crescent femoral stem of a plurality of handles, the eccentricity of each femoral stem all is located 32mm-49 mm's within range, and the high variation range less than or equal to 7mm of neck of a plurality of femoral stems, the neck height of femoral stem does not have obvious increase trend along with the increase of false body model size promptly, the high variation range of neck is no longer than 7mm, the value scope can be at 23-30mm, this is the obvious difference with current product, current product neck height increases obviously. By the arrangement, the offset and the neck height of each crowd can be recovered to the maximum extent, so that the hip abduction lever arm is recovered, and most people can be well matched. The utility model provides a selection to real crowd's more suitable offset and the high setting of neck to make the effectual abductor arm of force of recovering of patient and suitable leg length, obtain good postoperative effect.

In the utility model, the handle length of a plurality of femoral handles (especially the length of the inner handle) can be within the range of 93mm-153 mm.

For example, when the stem length of the femoral stem ranges from [93mm,107mm ], the eccentricity of the femoral stem ranges from 32mm to 41mm, and the neck height ranges from 23mm to 30mm.

As another example, when the stem length of the femoral stem is in the range of (107mm, 113mm), the femoral stem has an eccentricity of 36mm to 43mm and a neck height of 23mm to 30mm.

For another example, when the stem length of the femoral stem is in the range of 113mm,125mm, the eccentricity of the femoral stem is 37mm to 49mm, and the neck height is 23mm to 30mm.

In the utility model, the femoral stem in the femoral stem system can be a bone cement type or a non-bone cement type, the specific structure can be various conventional structural forms in the field, in one embodiment, as shown in fig. 4, the bone cement type and the non-bone cement type femoral stem can be rectangular double taper stems; in another embodiment, as shown in fig. 5, both the cement-type and non-cement-type femoral stems may be provided with grooves for the stem body (the grooves may include elongated grooves on the distal side of the stem body for increasing the contact area), the stem body being a rectangular double taper stem; in another embodiment, as shown in fig. 6, the stem bodies of the bone cement type and non-bone cement type femoral stems can be provided with grooves and vertical ridges (the characteristics of the grooves are that the contact area is increased, 2-4 vertical ridges are embedded into cancellous bone to play a role of stable fixation, and the outer side notch at the far end of the stem body is convenient for implanting the femoral stem).

On the other hand, the utility model provides a hip joint prosthesis system, including a plurality of hip joint prostheses, each hip joint prosthesis all includes the femoral stem in bulb and the foretell femoral stem system, and the bulb is connected with the free end of the neck of femoral stem. Since the structure of the femoral stem system is the same as above, it will not be described herein again.

The utility model discloses a hip joint prosthesis system, including the long crescent femoral stem of a plurality of handles, the eccentricity of each femoral stem all is located 32mm-49 mm's within range, and the variation range less than or equal to 7mm of the neck height of a plurality of femoral stems, and the neck height of femoral stem does not have obvious increase trend along with the increase of prosthesis model size promptly, and the neck height variation range is no longer than 7mm, and the value scope can be at 23-30mm, this be with the obvious difference of current product, current product neck height increases obviously. By the arrangement, the offset and the neck height of each crowd can be recovered to the maximum extent, so that the hip abduction lever arm is recovered, and most people can be well matched. The utility model provides a selection to true crowd's more suitable offset and neck height setting to make the effectual abductor arm of force of recovering of patient and suitable leg length, obtain good postoperative effect.

Considering that the ball heads usually have different specifications for selection (fig. 8), after the ball heads with different specifications are adopted, the eccentricity of the hip joint prosthesis is correspondingly changed (different from the eccentricity of a single femoral stem), preferably, the eccentricity of the hip joint prosthesis is in the range of 30mm-57mm, the variation range of the neck heights of a plurality of hip joint prostheses is less than or equal to 17mm, namely, the adjustment is carried out by adding the ball heads with different specifications to reach a larger comprehensive neck height range of 17mm, so that the adaptability of the hip joint prosthesis is better. It is further preferred that the neck height of the hip prosthesis is in the range of 20mm-37 mm.

The present invention relates to a femoral stem system and a hip joint prosthesis system, which will be described below with reference to specific examples.

Example 1 (for femoral stem prosthesis with shorter stem length shown in fig. 4):

the relevant parameter ranges for this prosthesis are shown in table 1 below.

TABLE 1 (units of size are mm)

In the table 1, the prosthesis models are divided according to the different lengths of the femoral stems, and are specifically divided into 11 models, namely 1#, 2#, 8230 \8230, 11#; the eccentricity (namely the basic handle offset) of each femoral handle is within the range of 32mm-49mm, the neck heights (namely the basic handle neck heights) of the femoral handles are within the range of 23mm-30mm, and the variation range of the neck heights is less than or equal to 7mm; the stem lengths of the plurality of femoral stems are in the range of 93mm-125 mm. The 'offset range suggestion (after the ball head is arranged)' corresponds to the eccentricity of the hip joint prosthesis after the combination of the ball head and the femoral stem, and the 'neck height range suggestion (after the ball head is arranged)' corresponds to the neck height of the hip joint prosthesis after the combination of the ball head and the femoral stem.

Example 2 (for femoral stem prosthesis with longer stem length shown in fig. 5):

the relevant parameter ranges for this prosthesis are shown in table 2 below.

TABLE 2 (units of size are mm)

In the table 2, the prosthesis models are also divided according to different stem lengths of femoral stems, specifically divided into 11 models, namely 1#, 2#, 8230, 8230and 11#; the eccentricity (namely the basic handle offset) of each femoral handle is within the range of 32mm-49mm, the neck heights (namely the basic handle neck heights) of the femoral handles are within the range of 23mm-30mm, and the variation range of the neck heights is less than or equal to 7mm; the stem lengths of the plurality of femoral stems are in the range of 95mm-153 mm. The offset range (after the ball head is arranged) is recommended to correspond to the eccentricity of the hip joint prosthesis after the combination of the ball head and the femoral stem and is within the range of 30mm-55mm, the neck height range (after the ball head is arranged) is recommended to correspond to the neck height of the hip joint prosthesis after the combination of the ball head and the femoral stem and is within the range of 20mm-37mm, and the variation range of the neck height is less than or equal to 17mm.

Example 3 (femoral stem prosthesis centered on stem length shown in fig. 6):

the relevant parameter ranges for this prosthesis are shown in table 3 below.

TABLE 3 (all size units are mm)

In the table 3, the prosthesis models are also divided according to different stem lengths of femoral stems, specifically divided into 11 models, namely 1#, 2#, 8230, 8230and 11#; the eccentricity (namely the basic handle offset) of each femoral handle is within the range of 32mm-49mm, the neck heights (namely the basic handle neck heights) of the femoral handles are within the range of 23mm-30mm, and the variation range of the neck heights is less than or equal to 7mm; the stem lengths of the plurality of femoral stems are in the range of 95mm-143 mm. The offset range (after the ball head is arranged) is recommended to correspond to the eccentricity of the hip joint prosthesis after the combination of the ball head and the femoral stem and is within the range of 30mm-55mm, the neck height range (after the ball head is arranged) is recommended to correspond to the neck height of the hip joint prosthesis after the combination of the ball head and the femoral stem and is within the range of 20mm-37mm, and the variation range of the neck height is less than or equal to 17mm.

To sum up, the utility model discloses a with the automatic good back that matches of hip joint prosthesis and human femoral medullary cavity, obtain corresponding law after carrying out human big data measurement to design out femoral stem and hip joint prosthesis's corresponding size, this size is implanted the use with clinical and has carried out strict verification, but each crowd's of furthest's recovery offset and neck height value, thereby resume hip joint abduction lever arm, make most people match well.

Through tests, when the femoral stem/hip joint prosthesis shown in the figures 4-6 of the utility model is adopted, the parameter ranges are shown in the tables 1-3, the offset and the neck height value of each population can be recovered to the maximum extent, so that the hip joint abduction lever arm is recovered, the match of most people is good, and the good match rate is 98%; and the good matching rate of the conventional hip joint prosthesis femoral stem in the prior art is only 59 percent (the proportion of the difference of the post-operation leg length exceeds 10mm accounts for 41 percent of people).

The foregoing is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims (10)

1. A femoral stem system is characterized by comprising a plurality of femoral stems with gradually increased stem lengths, wherein the eccentricity of each femoral stem is within the range of 32-49 mm, and the variation range of the neck heights of the plurality of femoral stems is less than or equal to 7mm.

2. The femoral stem system of claim 1, wherein the neck height is in the range of 23mm-30mm.

3. The femoral stem system of claim 1, wherein the stem lengths of a plurality of the femoral stems each lie in the range of 93mm-153 mm.

4. The femoral stem system of claim 3, wherein the femoral stem has a stem length in the range of [93mm,107mm ], an eccentricity of 32mm to 41mm, and a neck height of 23mm to 30mm.

5. The femoral stem system of claim 3, wherein the femoral stem has a stem length in the range of (107mm, 113mm), an eccentricity of 36mm to 43mm, and a neck height of 23mm to 30mm.

6. The femoral stem system of claim 3, wherein the femoral stem has a stem length in the range of [113mm,125mm ], an eccentricity of 37mm to 49mm, and a neck height of 23mm to 30mm.

7. The femoral stem system of claim 1, wherein the stem body of the femoral stem is a rectangular double taper stem;

or the handle body of the femoral handle is provided with a groove and is a rectangular double-taper handle;

or the handle body of the femoral handle is provided with a groove and a vertical ridge.

8. A hip joint prosthesis system, comprising a plurality of hip joint prostheses, each of which comprises a ball head and a femoral stem in the femoral stem system according to any one of claims 1 to 7, the ball head being connected to a free end of a neck portion of the femoral stem.

9. The hip prosthesis system according to claim 8, wherein the eccentricity of said hip prosthesis is in the range of 30-57mm, and the variation of the neck height of a plurality of said hip prostheses is less than or equal to 17mm.

10. The hip prosthesis system according to claim 9, wherein the neck height of the hip prosthesis is in the range of 20-37 mm.

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