US20080125778A1

US20080125778A1 - Method for fixing an augmenter for vertebral body reconstruction

Info

Publication number: US20080125778A1
Application number: US11/599,305
Authority: US
Inventors: Kung-Chia Li
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-10-05
Filing date: 2006-11-15
Publication date: 2008-05-29
Also published as: CA2487227A1; EP1658830A1; US20060085007A1; US7500992B2

Abstract

A method for fixing an augmenter for vertebral body reconstruction includes following steps: incising a middle of a portion of a rear side of a person's body that faces a collapsed section of a vertebra; establishing a correct position for insertion of an augmenter and drilling a fixing hole on a pedicle of said collapsed vertebral section; putting filler such as harvested autogenous bone, artificial bone, and bone cement into said fixing hole; inserting an augmenter into said fixing hole, and filling said fixing hole with filler such as harvested autogenous bone, artificial bone, and bone cement.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a method for fixing an augmenter for vertebral body reconstruction, more particularly one, according to which an augmenter can be inserted in and firmly joined to a collapsed section of a vertebra so as to enlarge the collapsed vertebral section and restore the vertebra to its original position.
2. Brief Description of the Prior Art
Osteoporosis is a disease in which calcium content of bones gradually decreases, and in turns, bones become fragile and more likely to break. If not prevented or if left untreated, osteoporosis can progress to make bones become subject to breakage. Breakage of bones related to osteoporosis usually occurs in the spine.
Certain people are more likely to develop osteoporosis than others. Risk factors have been identified as followings, which will increase the likelihood of developing osteoporosis:
1. Being Caucasian or Asian; average skeletal mass of Caucasian and Asian is lower than that of black people, and Caucasian and Asian are more likely than black people to develop osteoporosis;
2. An improper lifestyle; use of alcohol, cigarette, excessive use of coffee, tea, and excessive or lack of exercises;
3. A family history of osteoporosis;
4. Use of certain medications, such as corticosteroids, and anticonvulsants;
5. Estrogen deficiency as a result of menopause, especially early or surgically induced in women or low testosterone levels in men; and 6. Being female and/or having a small frame; females who have never given birth to babies or had their first menstrual period at older age.
A conventional method of treating osteoporosis-related fracture is to insert steel nail into a vertebra from rear side of the vertebra. This method has the following disadvantages:
1. Two vertebras above the fractured vertebra and two under the fractured vertebra have to be fixed if this method is used. Consequently, a big portion of the spine becomes stiff, flexibility of the spine is reduced to a large degree.
2. A vertebra, which has fractured due to osteoporosis, is likely to become unsteady and fracture again after restoration of position with steel nails.
3. A relatively large incision has to be formed on the patient's back, and it takes relatively much time to perform the surgery and for the incision to heal, and the incision is prone to become infected.
Another conventional method of treating osteoporosis-related fracture is to insert steel nail into a vertebra from front side of the vertebra. This method has the following disadvantages:
1. Surgical equipments will have to be passed through thoracic cavity or abdominal cavity of the patient in operation therefore nearby organs, e.g. lungs and blood vessels, could be at risk.
2. It takes relatively much time to perform the surgery. And, there is risk of infection because donated bones or ribs of the patient from front side of the vertebra will be used according to this method.
3. It also will cause reduction of the flexibility of the spine.

SUMMARY OF THE INVENTION

It is a main object of the invention to provide an improvement on a method for fixing an augmenter for vertebral body reconstruction to overcome the above-mentioned problems.
The method of the present invention includes the following steps: incising a middle of a portion of a rear side of a person's body that faces a collapsed section of a vertebra; establishing a correct position for insertion of an augmenter and drilling a fixing hole on a pedicle of said collapsed vertebral section; putting filler such as harvested autogenous bone, artificial bone, and bone cement into said fixing hole; inserting an augmenter into said fixing hole, and filling said fixing hole with filler such as harvested autogenous bone, artificial bone, and bone cement. Therefore, the method of the present invention has the following advantages over the currently existing ones: The incision is relatively small, and will heal in relatively short length of time, and will not become infected. It takes less time to operate and plant the augmenters. There is no risk of the patient's organs and blood vessels getting injured. And, the augmenters won't cause other healthy vertebras to lose the freedom to move.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood by referring to the accompanying drawings, wherein:

FIG. 1 is a flow chart of the present invention,

FIG. 2 is a perspective view of the first augmenter for vertebral body reconstruction in the invention,

FIG. 3 is an exploded perspective view of the second augmenter in the invention,

FIG. 4 is an exploded perspective view of the third augmenter,

FIG. 5 is an exploded perspective view of the fourth augmenter,

FIG. 6 is an exploded perspective view of the fifth augmenter,

FIG. 7 is a sectional view of the fifth augmenter,

FIG. 8 is a view taken when the first augmenter is put into use,

FIG. 9 is a view taken when the second augmenter is put into use,

FIG. 10 is a view taken when the third augmenter is put into use,

FIG. 11 is a view taken when the fourth augmenter is put into use,

FIG. 12 is a view taken when the fifth augmenter is put into use,

FIG. 13 is a view taken when the first augmenter is put into use (2),

FIG. 14 is a view taken when the second augmenter is put into use (2), and

FIG. 15 is a view taken when the fifth augmenter is in use (2).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, a method for fixing an augmenter for vertebral body reconstruction includes the following steps:
(a) We find out which section of a vertebral body 2 is damaged (collapsed), and incise a middle of a portion of a rear side of the patient's body that faces the damaged vertebral section, and we peel off the soft tissues, and separate the vertebral bows, small-faced joints, and transverse processes;
(b) We establish the correct position for insertion of the augmenter with the help of a C-arm fluoroscopy, and drill a fixing hole 22 on the damaged vertebral section 2, through a pedicle 21 of the section 2;
(c) We enlarge the image of the fixing hole 22 for following fixing actions by means of a magnifier;
(d) We put filler such as harvested autogenous bone, artificial bone, and bone cement into the fixing hole 22;
(e) We insert an augmenter 1, 3 or 4 into the fixing hole 22, and establish that the augmenter 1, 3, 4 is in the correct position by means of a C-arm fluoroscopy;
(f) Finally, we fill the fixing hole 22 with filler such as harvested autogenous bone, artificial bone, and bone cement so as to level out the vertebral body 2 and prevent the augmenter 1, 3, 4 from falling off.
Referring to FIG. 2, a first preferred embodiment of an augmenter 1 is rectangular, and tapers off from a second end 12 towards a first end 11 thereof, and has a slightly convexly curved shape with a coarse surface for helping bone to grow as well as increasing firmness of connection between the augmenter 1 and the vertebral body 2. The augmenter 1 has a screw hole 14 extending from the second end 12 towards the first end 11; thus, a planting tool can be passed into the screw hole 14, and joined to the augmenter 1 for helping insert the augmenter 1 into the vertebral body 2. Referring to FIG. 8, the augmenter 1 will enlarge the vertebral body 2 after it is inserted in the fixing hole 22 of the vertebral body 2.
Referring to FIG. 3, a second preferred embodiment of an augmenter 3 consists of upper and lower planted bars 31 and 32, and a wedge-shaped bar 33. The upper and the lower planted bars 31 and 32 have a coarse surface. The upper planted bar 31 has an uppermost portion 311, an insertion portion 312 projecting down from a lower side of the uppermost portion 311, longitudinal fitting gaps 313 on lateral sides of front and rear ends of the insertion portion 312, and a convexly curved base portion 314 at a rear end thereof. Furthermore, the upper planted bar 31 has a screw hole 315 on a front end thereof for a tool to be connected to, which tool is used for planting the upper and the lower planted bars 31 and 32 into the vertebral body 2.
The lower planted bar 32 has a holding room 321, which has an opening facing upwards, for receiving the insertion portion 312 of the upper planted bar 31. The lower planted bar 32 has first and second openings 322 and 323 on front and rear ends respectively; the first opening 322 has a T-shape, and the second opening 323 has an U-shape. The lower planted bar 32 has lateral portions 324 on two sides of the first opening 322 and on two sides of the second opening 323, and the lateral portions 324 will be received in the fitting gaps 313 of the upper planted bar 31 when the upper planted bar 31 is inserted in the lower planted bar 32.
The wedge-shaped bar 33 is inserted in the holding room 321 of the lower planted bar 32, between the upper and the lower planted bars 31 and 32, for changing the volume of the whole augmenter 3. In addition, the wedge-shaped bar 33 has a screw hole 331 on a front end thereof for a tool to be connected to.
Referring to FIG. 9, to plant the augmenter 3 into a damaged vertebral section 2, first a tool is used to drill a fixing hole 22 on the vertebral section 2 through a pedicle 21 of the vertebral section 2. Second, the upper planted bar 31 is inserted in the lower planted bar 32 at the insertion portion 312, and a tool is passed into the screw hole 315 of the upper planted bar 31, and the upper and the lower planted bars 31 and 32 together are inserted in the fixing hole 22 of the vertebral section 2 with the help of the tool. Next, a tool is passed into the screw hole 331 of the wedge-shaped bar 33, and the wedge-shaped bar 33 is inserted in the holding room 321 of the lower planted bar 32, between the upper and the lower planted bars 31 and 32, with the help of the tool; thus, the upper and the lower planted bars 31 and 32 are propped upwards and downwards respectively by the wedge-shaped bar 33, thus the vertebral section 2 is propped, and the vertebra restored to its original position.
FIG. 4 shows a third preferred embodiment of an augmenter for vertebral body reconstruction in the present invention; the upper planted bar 31 of the above-mentioned augmenter 3 is further formed with a concavely curved surface 316 on a lower side of the insertion portion 31 thereof, and the concavely curved surface 316 has several threads 316 a thereon; the lower planted bar 32 is further formed with a concavely curved surface 325 on a bottom thereof, which faces the holding room 321, and the concavely curved surface 325 has several threads 325 a thereon. In use, a threaded element 34 is inserted between the concavely curved surfaces 316 and 325 of the upper and the lower planted bars 31 and 32 to engage the threads 316 a, 325 a; thus, the upper and the lower planted bars 31 and 32 are propped upwards and downwards respectively by the threaded element 34, as shown in FIG. 10.
FIG. 5 shows a fourth preferred embodiment of an augmenter for vertebral body reconstruction; the lower planted bar 32 of the above-mentioned augmenter 3 is further formed with several holes 326 on a front end thereof for another tool to be connected to, as shown in FIG. 10. Thus, the augmenter 3 can be inserted in a vertebral body more easily with the help of the tool. And, the wedge-shaped bar 33 further has a downwards sticking extension portion 332 at the front end, which will be stopped by the front end of the lower planted bar 32 when the wedge-shaped bar 33 is inserted in the lower planted bar 32; thus, the front ends of the upper planted bar 31 and the wedge-shaped bar 33 will be coplanar when the augmenter 3 is put into use, as shown in FIG. 11.
Referring to FIGS. 6 and 7, a fifth preferred embodiment of an augmenter 4 consists of an upper planted bar 41, and a lower planted bar 42, both of which have a coarse surface.
The upper planted bar 41 has an uppermost portion 411, an insertion portion 412 on a lower side of the uppermost portion 411, and stopping post portions 414 protruding down from a rear end of the uppermost portion 411. The insertion portion 412 has a convexly curved lower side 412 a with a parabola-shape, and protruding portions 413 protruding sideways from two lateral sides of a lower end thereof.
The lower planted bar 42 has a fitting trench 421, which has an upward opening as well as a concavely curved lower side 421 a with a parabola-shape. The lower planted bar 42 further has guide grooves 422 next to two sides of a lower end of the fitting trench 421; thus, the protruding portions 413 will be received in respective ones of the guide grooves 422 when the insertion portion 412 of the upper planted bar 41 is fitted on the fitting trench 421. The lower planted bar 42 further has a screw hole 423 on a front end, and holding portions 424 on a rear end for receiving the stopping post portions 414 of the upper planted bar 41.
Referring to FIG. 12, to plant the augmenter 4 into a damaged vertebral section 2, first a tool is used to drill a fixing hole 22 on the vertebral section 2 through a pedicle 21 of the vertebral section 2. Second, the upper and the lower planted bars 41 and 42 are joined together with the insertion portion 412 of the upper planted bar 41 being fitted on the fitting trench 421 of the lower planted bar 42, and a tool is passed into the screw hole 423 of the lower planted bar 42, and the planted bars 41 and 42 together are inserted in the fixing hole 22 of the vertebral section 2 with the help of the tool. Next, the upper planted bar 41 is moved and adjusted in position in relation to the lower planted bar 42; because the insertion portion 412 of the upper planted bar 41 is fitted on the fitting trench 421 of the lower planted bar 42, and the sideways protruding portions 413 are received in the guide grooves 422, the longitudinal dimension of the whole augmenter 4 will be changed when the upper planted bar 41 is adjusted in position in relation to the lower planted bar 42. Consequently, the planted bars 41 and 42 are propped upwards and downwards respectively, thus the vertebral section 2 is propped, and the vertebra restored to its original position.
Referring to FIGS. 13 to 15, if it is necessary, a screw system 5 can be applied to both of the vertebral sections next to the damaged vertebral section 2 for helping increase stability of the spine after the augmenter 1, 3 or 4 of the present invention is planted.
The dimension of the augmenters 1, 3 and 4 is decided according to the vertical cross-section and the height of the pedicle 21 of the vertebral section 2; the vertical cross-section of the pedicle 21 is close to a rectangle, and somewhat oval, and the distance between an upper end and a lower end of the pedicle 21 is greater than that between a left side and a right side; the ratio of the height of pedicle 21 to the height of the vertebral section 2 is between 0.5 and 0.6. Therefore, the augmenter can be made with a size near to the pedicle 21 so that at least 50% to 60% of the vertebra 4 is reconstructed. Consequently, 70% to 80% of the vertebral section 2 will be reconstructed when the augmenter is combined with the remaining bone mass of the damaged vertebral section 2. Furthermore, the height of the augmenters (the second, the third, the fourth and the fifth preferred embodiments) will be changed up to 20 or 30% by means of changing the longitudinal dimension of the augmenter, and in turns, the vertebral section 2 can be nearly restored to the original size, which it had before the fracture. Therefore, with the help of the augmenter, the vertebra can be restored to the original position.
Because the above augmenters are planted into a collapsed vertebra through a pedicle of the vertebra instead of via the thoracic or abdominal cavity of the patient therefore the operation is relatively safe as compared with the last conventional way described in the Background, and mechanical strength of the vertebra is increased.
The augmenters 3 (the second and the fourth preferred embodiment) each consists of upper and lower planted bars 31 and 32, which can be propped upwards and downwards respectively with the help of the wedge-shaped bar 33 to adjust the longitudinal dimension of the augmenter according to needs. And, the augmenter 3 (the third preferred embodiment) consists of upper and lower planted bars 31 and 32, which can be propped upwards and downwards respectively to increase the longitudinal dimension of the augmenter with the help of the threaded element 34. The augmenter (the fifth preferred embodiment) consists of an upper planted bar 31 having a convexly curved lower side with a parabola-shape, and a lower planted bar 32, which has a concavely curved upper side touching the convexly curved lower side of the upper planted bar 31; thus, longitudinal dimension of the augmenter 4 will be changed when the upper planted bar 41 is adjusted in position in relation to the lower planted bar 42. Therefore, a damaged vertebral section can be restored to its original height and width after one of the augmenters is inserted and adjusted in longitudinal dimension, and bone draft is used to fill up the vertebral section. Furthermore, because the augmenters are coarse, having many small protrusions spread out on the surface, stability of connection of bone mass of the vertebral section will increase, and the augmenters can help bone heal. And, the augmenters can be used alone on a collapsed vertebra without having to carry out operation on other healthy vertebras near to the collapsed one, which operation could cause the other healthy vertebras to lose the freedom to move.
From the above description, it can be seen that the present invention has the following advantages:
1. The augmenters can be used alone on a collapsed vertebra without the need for operation being done on other healthy vertebras near to the collapsed one, which operation would cause damage and loss of freedom of motion to the other healthy vertebras.
2. The augmenters can be adjusted in their longitudinal dimension according to needs after they are inserted in a collapsed vertebra.
3. Doctors have to drill a hole on only that section of a vertebra that is collapsed, and the incision is relatively small therefore the incision will heal in relatively short length of time, and will not become infected.
4. It takes less time to operate and plant the augmenters.
5. Because the augmenters are planted from the rear side of the patient's body therefore there is no risk of the patient's organs and blood vessels getting injured.
6. The augmenters are only inserted in the collapsed vertebra therefore they won't cause other healthy vertebras to lose the freedom to move.

Claims

1. A method for fixing an augmenter for vertebral body reconstruction, comprising following steps:

(a) incising a middle of a portion of a rear side of a person's body that faces a collapsed section of a vertebra;

(b) establishing a correct position for insertion of an augmenter and drilling a fixing hole on said collapsed vertebral section, through a pedicle of said collapsed vertebral section;

(c) putting fillers into said fixing hole;

(d) inserting an augmenter into said fixing hole; and

(e) filling said fixing hole with fillers.

2. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein in drilling said fixing hole, the correct position for insertion of the augmenter is established with help of a C-arm fluoroscopy.

3. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein an image of said fixing hole is enlarged by means of a magnifier.

4. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein a C-arm fluoroscopy is used to establish that said augmenter is in the correct position after said augmenter is inserted into said fixing hole.

5. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein a screw system is applied to those of the vertebra that are next to said collapsed vertebral section for increasing healing speed of said vertebra.

6. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein the filler used in step (c) is harvested autogenous bone.

7. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein the filler used in step (c) is artificial bone.

8. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein the filler used in step (c) is bone cement.

9. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 1, wherein the filler used in step (e) is harvested autogenous bone.

10. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 6, wherein the filler used in step (e) is artificial bone.

11. The method for fixing an augmenter for vertebral body reconstruction as recited in claim 6, wherein the filler used in step (e) is bone cement.