U.S. patent number RE35,940 [Application Number 08/604,381] was granted by the patent office on 1998-10-27 for electromechanical back brace apparatus.
This patent grant is currently assigned to Bio-Cybernetics, International. Invention is credited to Thomas J. Heinz, Eric D. Plambeck, Thomas A. Walker.
United States Patent |
RE35,940 |
Heinz , et al. |
October 27, 1998 |
**Please see images for:
( Certificate of Correction ) ( Reexamination Certificate
) ** |
Electromechanical back brace apparatus
Abstract
A back brace apparatus disclosed which has electromechanical
means for tightening a brace around the trunk of a patient to a
desired tension. The electromechanical means is controllable by the
patient to effect predetermined tension settings. A cable and
pulley arrangement tightened by a motor provides a mechanical
advantage so that the brace may be tightened by a small motor. A
microprocessor controls the motor to obtain the desired repeatable
tension settings.
Inventors: |
Heinz; Thomas J. (Flintridge,
CA), Walker; Thomas A. (Ojai, CA), Plambeck; Eric D.
(Ventura, CA) |
Assignee: |
Bio-Cybernetics, International
(Flintridge, CA)
|
Family
ID: |
25509775 |
Appl.
No.: |
08/604,381 |
Filed: |
February 21, 1996 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
965305 |
Oct 23, 1992 |
05346461 |
Sep 13, 1994 |
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Current U.S.
Class: |
602/19; 128/96.1;
128/121.1 |
Current CPC
Class: |
A61F
5/028 (20130101) |
Current International
Class: |
A61F
5/02 (20060101); A61F 005/00 () |
Field of
Search: |
;602/19,32,33,36 ;24/32
;182/4 ;128/96.1,99.1,100.1,121.1,125.1,379,380,384,385 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Dvorak; Linda C.
Attorney, Agent or Firm: Nikaido, Marmelstein, Murray &
Oram LLP
Claims
What is claimed is:
1. A back brace apparatus comprising:
a brace body adapted to be wrapped around the trunk of a patient,
said brace body comprising two separate segments;
means at the end of each brace segment for allowing the two ends to
be detachably connected together around the patient's trunk;
and,
means for automatically tightening the brace comprising a cable
operatively connected to said two segments, a motor operatively
connected to apply tension to said cable, means for controlling
said motor, a reduction gear train connected to said motor, a worm
attached to said gear train, a worm gear engaged with said worm, a
spool connected to said worm gear to which is attached one end of
the cable with the other end of the cable affixed to the other
brace segment so that operation of the motor shortens or lengthens
the cable in order to tighten or loosen the brace.
2. The back brace apparatus as set forth in claim 1, wherein said
brace segments are held together by said cable.
3. The back brace apparatus as set forth in claim 1 wherein the
cable is run through at least one pulley mounted on one of the
brace segments.
4. The back brace apparatus as set forth in claim 1 further
comprising means for storing data including time and associated
brace tension settings and brace tension, and means for outputting
said data for use by a health care professional.
5. The back brace apparatus as set forth in claim 1, wherein said
means for allowing the two ends of the brace segments to be
detachably connected together comprises a section of hook-and-loop
fastener material on each of the ends.
6. A back brace apparatus comprising:
a brace body adapted to be wrapped around the trunk of a patient,
said brace body comprising two separate segments;
means at the end of each brace segment for allowing the two ends to
be detachably connected together around the patient's trunk;
and,
means for automatically tightening the brace comprising a cable
operatively connected to said two segments, a motor operatively
connected to apply tension to said cable, means for a set of
pulleys mounted on each controlling said motor, and brace segment
with the cable running through a pulley on each segment in
alternation, shortening of the cable pulling the two brace segments
together and tightening the brace with the aid of a mechanical
advantage dependent upon the number of pulleys mounted on each
brace segment.
7. A back brace apparatus comprising:
a brace body adapted to be wrapped around the trunk of a patient,
said brace body comprising two separate segments;
means at the end of each brace segment for allowing the two ends to
be detachably connected together around the patient's trunk;
and,
means for automatically tightening the brace comprising a cable
operatively connected to said two segments, a motor operatively
connected to apply tension to said cable, means for controlling
said motor comprising a microprocessor for controlling the
operation of the motor by controlling the number of revolutions
made by the motor; and means for inputting the number of
revolutions made by the motor into the microprocessor;
wherein the microprocessor can store for later recall the number of
revolutions made by the motor, the stored number thereby
constituting a position setting for the brace.
8. A back brace apparatus comprising:
a brace body adapted to be wrapped around the trunk of a patient,
said brace body comprising two separate segments;
means at the end of each brace segment for allowing the two ends to
be detachably connected together around the patient's trunk;
means for automatically tightening the brace comprising a cable
operatively connected to said two segments a motor operatively
connected to apply tension to said cable, and means for controlling
said motor; and
means for atuomatically loosening the brace tension when the brace
is taken off of a user comprising means to periodically sense the
tension of the brace, means to store information of a last user
input, means to compare tension of the brace with what it should be
in accordance with the last user input, and means for spreading the
brace segments when the tension sensed is substantially less than
what it should be in accordance with the last user input.
9. The back brace apparatus as set forth in claim 8, wherein said
means for periodically sensing the tension of the brace comprises
means for momentarily turning the motor on and determining
load.
10. A back brace apparatus comprising:
a brace body adapted to be wrapped around the trunk of a patient,
said brace body comprising two separate segments;
means at the end of each brace segment for allowing the two ends to
be detachably connected together around the patient's trunk;
means for automatically tightening the brace comprising a cable
operatively connected to said two segments, a motor operatively
connected to apply tension to said cable, and means for controlling
said motor;
means for determining whether user has removed said brace without
loosening the tension setting and for operating said means for
controlling said motor to loosen said cable; and
means for loosening the tension setting and unspooling the
cable.
11. The back brace apparatus as set forth in claim 10, wherein said
means for determining whether user has removed said brace without
loosening the tension setting and for operating said means for
controlling said motor to loosen said cable comprises means for
periodically sensing the tension of the brace by momentarily
turning the motor and checking the motor current consumption, means
for comparing motor current consumption with what it should be in
accordance with the last user input and means for operating said
motor to unspool said cable when said motor current consumption is
substantially less than what it should be in accordance with the
last key input.
12. The back brace apparatus as set forth in claim 10, wherein said
means for unloosening the tension setting and unspooling the cable
comprises spring means for spreading said brace segments apart upon
loosening of said cable.
13. The back brace apparatus as set forth in claim 10, wherein said
means for determining whether user has removed said brace without
loosening the tension setting and for operating said means for
controlling said motor to loosen said cable comprises means for
periodically sensing the tension of the brace, means to store
information of a last user input, means to compare tension of the
brace with what it should be in accordance with the last user
input, and means for operating said motor to unspool said cable
when the tension sensed is substantially less than what it should
be in accordance with the last user input.
14. The back brace apparatus as set forth in claim 13, wherein said
means for periodically sensing the tension of the brace comprises
means for momentarily turning the motor on and determining
load.
15. The back brace apparatus as set forth in claim 13, wherein said
means for loosening the tension setting and unspooling the cable
comprises spring means for spreading said brace segments apart upon
loosening of said cable. .Iadd.
16. A back brace apparatus comprising:
a brace body adapted to be wrapped around the trunk of a patient,
said brace body comprising two separate segments;
means at the end of each brace segment for allowing the two ends to
be detachably connected together around the patient's trunk;
a cable operatively connected to said two segments; and
a set of pulleys mounted on each brace segment with the cable
running through a pulley on each segment in alteration, shortening
of the cable pulling the two segments together and tightening the
brace apparatus with the aid of a mechanical advantage dependent
upon the number of pulleys mounted on each brace
segment..Iaddend..Iadd.17. The back brace apparatus as set forth in
claim 16, further comprising a pair of plates, said plates being
detachably mounted on said segments, said set of pulleys being
mounted on said plates..Iaddend..Iadd.18. The back brace apparatus
as set forth in claim 17, wherein said pulleys are mounted on each
plate at staggered positions relative to the other
plate..Iaddend..Iadd.19. The back brace apparatus as set forth in
claim 16, wherein said means for allowing the two ends to be
detachably connected together comprises a section of hook-and-loop
fastener material on each of the ends..Iaddend..Iadd.20. The back
brace apparatus as set forth in claim 16, further comprising spring
means for spreading said brace segments apart upon loosening of
said cable..Iaddend.
Description
BACKGROUND OF THE INVENTION
A common method of alleviating pain and promoting healing in
post-operative back surgery patients and those otherwise suffering
from back injuries is to stabilize the spine by means of a brace.
Such braces typically comprise a corset made of canvas or similar
material which can be snugly fitted around the patient's trunk. The
back portion of the corset usually has pockets into which are
inserted rigid stays for providing vertical support.
Such braces are effective if worn properly and consistently, but
most patients have difficulty manually adjusting the brace to a
tight enough fit for providing adequate support. This is especially
true in the case of post-operative paitents who are in pain and
lack sufficient strength. Such patient non-compliance obviously
reduces the effectiveness of the brace.
Another problem with these types of braces is their inability to
adapt as the patient moves from a standing to a sitting position.
That is, the patient is required to make any necessary adjustments
manually to vary the tension depending on whether standing or
sitting. Further, it is extremely difficult to adjust the brace to
have exactly the same amount of tension or even to set a particular
tension for a particular patient.
SUMMARY OF THE INVENTION
The present invention is a corset-type back brace which is
tightened around a patient by a motor which can be computer
controlled. The brace comprises two segments linked together by a
cable. The two segments can be physically separate pieces or can be
portions of the same brace body.
At the free ends of each brace segment is a section of
hook-and-loop fastener material for connecting the two free ends
when the brace is wrapped around the trunk of a patient. The motor
is mounted to one of the segments. The cable is connected at one
end to a driven shaft or gear of the motor and to the brace body at
the other end so that, as the cable is reeled in by the motor, the
brace is cinched tight and tensioned.
In one embodiment, the cable is run through a pulley mounted on the
brace segment opposite from the motor, with the fixed end of the
cable attached to the same brace segment as the motor to result in
a 2:1 mechanical advantage when tightening the brace around a
patient's trunk. By mounting a series of pulleys on each brace
segment and running the cable through them serially, a greater
mechanical advantage may be obtained. This reduces the necessary
size of the motor. Additionally, the size of the entire apparatus
is reduced leading to a less bulky appearance of the back brace and
less discomfort for the patient.
The brace can also comprise a microprocessor mounted on the brace
body for controlling the operation of the motor. The microprocessor
can be appropriately programmed so that the brace is tightened to a
predetermined setting, with separate repeatable settings for
sitting and standing positions. The microprocessor can also
function as a data collection device for monitoring patient
compliance. The microprocessor does not need to be at the position
of the motor and can be mounted at any place on the back brace. The
microprocessor can be mounted to the brace body using a section of
hook-and-loop fastener material.
It is preferable that the back brace be operated by a user
interface keypad device. The keypad device can have an LCD readout
which indicates relative tightness. The microprocessor may also
monitor battery condition and other feedback important to the user
and display the same on the readout both for the use of the patient
and for the use of a health care professional. The microprocessor
can alternatively be mounted in the user interface keypad device
remotely from the brace body and be linked to the motor by cable.
In such an embodiment, the keypad device can be mountable at any
place on the back brace by using a section of hook-and-loop
fastener material.
It is a first object of the present invention to provide a back
brace which may be tightened around a patient with little physical
effort on the part of the patient and yet provide the necessary
support.
It is a further object of the invention for the back brace to be
capable of being tightened automatically to a predetermined extent,
thus ensuring repeatability of patient treatment.
It is still a further object of the present invention to provide a
back brace enabling a health care professional to predetermine and
subsequently monitor patient treatment.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features, and advantages of the invention will
become evident in light of the following detailed description
considered in conjunction with the referenced drawings of a
preferred exemplary embodiment according to the present invention,
wherein:
FIG. 1 shows the back brace in accordance with the present
invention in its extended position;
FIG. 2 is a detailed view of the plates; and
FIG. 3 shows the front of the control module.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a planar view of one side of the back brace apparatus
in an extended position. The brace 10 comprises a brace body 11.
The brace body 11 is made of canvass or similar fabric and is
adapted to be wrapped around the trunk of a patient. A plurality of
elastic portions 16 can be provided along upper and lower edges of
the brace body for greater patient comfort during use. The brace
body 11 is made up of two brace segments 11a and 11b, each having
part of the means for automatically tightening the brace. A section
of hook-and-loop fastener fabric 18 is mounted on opposite sides of
each brace segment at the free ends opposite from the plates
described below for securing the two free ends together after the
brace is wrapped around the patient's trunk. Such material is
capable of withstanding a large amount of shear stress so that the
brace 10 may be kept under tension but can be easily peeled away
when the apparatus is to be taken off.
The means for automatically tightening the brace can include a
cable 12 and a plate 13a or 13b mounted on each brace segment. Each
plate 13a or 13b has a series of pulleys 15 mounted on it at
staggered positions relative to the other plate. The cable 12 runs
serially through the pulleys 15 and is fixed at each end in a
manner described more fully below so as to hold the brace segments
in position.
The brace segments can be held together at their ends by the cable.
Foldover or slip sleeve fabric covers can be provided for the cable
and plate portions of the brace. The plates 13 are detachably
mounted on the brace segments 11 by section of hook-and-loop
fastener fabric 18.
FIG. 2 shows part of the means for automatically tightening the
brace including the pair of plates 13a and 13b in greater detail.
An electric motor 35, a reduction gear train 32, a worm 33, and a
worm gear 31 are mounted on plate 13a and are mechanically coupled
together so that rotation of motor 35 causes rotation of worm gear
31. A spool 30 is coaxially attached to the worm gear 31 and cable
12 is attached at one end to the spool. The cable 12 is attached at
the other end to a fixed point 17 on the plate 13a. Motor 35 thus
reels in or out the cable 12 to determine the cable's length. Cable
12 runs through the pulleys 15 on each brace segment in alternating
fashion so that shortening of the cable by the motor 35 pulls the
two brace segments 11a and 11b closer together and tightens the
brace body 11 around the patient's trunk with a mechanical
advantage. That mechanical advantage is, of course, determined by
the number of pulleys and in the embodiment shown in FIG. 2 is
14:1; with the most preferred embodiment being 16:1.
The means for automatically tightening the brace further includes a
means 20 for controlling the operation of the motor. The means for
controlling the operation of the motor can include a control module
21 mounted on plate 13a. Alternatively, the means 20 can be
included in the keypad interface device 22 described hereinbelow.
In a preferred embodiment, the operation of the apparatus is
controlled by means of a microprocessor 40 within the module 21 to
minimize any power or signal loses.
A plurality of battery brackets (not shown) can also be mounted on
the plates together with the necessary wiring for powering the
motor. Wires (not shown) running between the plates provide
electrical connections for the transmission of power and signals as
necessary.
It is preferable that the back brace be operated by a user
interface keypad device 22. The keypad interface device 22 can be
provided for patient ease of use. A number of buttons which may be
accessed by the patient on the front panel 23 of the keypad
interface device. Buttons A and B loosen and tighten, respectively,
the brace 10 by controlling the length of the cable 12 with the
motor 35. In one embodiment during the tightening process, the
microprocessor counts the number of rotations made by the motor by
optically coupling the motor to the microprocessor's data input
circuitry. That number of motor rotations, constitutes a setting
for the brace and may be stored for later recall in the
microprocessor's memory by the use of the memory button F. If the
number of turns of the motor shaft is used as the setting for the
tension of the brace, the tension is repeatable for the same
patient, but is not presentable to a certain degree of tension.
In another embodiment, the microprocessor monitors and stores the
output of a strain gauge either connected within the fabric of the
brace or connected to the cable which measures the tension of the
brace. The strain gauge can be a spring loaded linear potentiometer
attached at the fixed end of the cable.
The preferred embodiment uses monitoring of the motor current as an
indirect indicator to measure the tension in the back brace. If the
motor 35 is driven by a MOSFET H-bridge, one of the MOSFETs used to
drive the motor can be used in conjunction with the resistor below
it. An A/D converter could be used to measure the voltage drop
across the resistor to indicate the motor current and thus the
relative tension on the cable which is proportional to the tension
of the brace. The motor current is periodically polled by the
microprocessor.
As an example of how the buttons on the keypad device 22 can be
used: to store a setting appropriate for the sitting position,
button F can be pressed in conjunction with button E. For the
standing position, button F can be pressed in conjunction with
button D. To recall these settings, the patient would press either
button D or E alone which causes the motor 35 to rotate to
establish the stored degree of tension. In this way, a patient may
easily adjust the setting of brace according to whether they are
sitting or standing. A toggle button C is also provided for
toggling between the sitting and standing tensions. The keypad
device 22 can be attached at any point to the brace and can be
connected to the microprocessor by wire. If the keypad device 22 is
provided with physical landmarks, the patient could retain it under
clothing and using tactile feedback, set and reset the tension of
the brace as desired.
The length of the cable 12 is effectively locked when the desired
setting is reached simply by the inherent effect of the worm gear
and worm together with the reduction gearing.
The keypad device can have an LCD readout 24 which indicates
relative tightness and whatever other information that the device
is programmed to deliver. The microprocessor may also monitor
battery condition and other feedback important to the user and
display the same on the readout both for the use of the patient and
for the use of a health care professional. The microprocessor can
alternatively be mounted in the user interface keypad device
remotely from the brace body and be linked to the motor by cable.
In such an embodiment, the keypad device can be mountable at any
place on the back brace by using a section of hook-and-loop
fastener material. It is most preferred that the keypad device be
connected to the microprocessor with the minimum of wires. That is,
it is most preferred that the keypad device be as autonomous as
possible. In this regard, the keypad device has its own power
supply and independent microprocessor and communicates with the
microprocessor in an asynchronous serial fashion.
An additional interface device can be connected to the
microprocessor together with a small peripheral electronic device
connectable to a personal computer to enable a health care
professional to download data stored in the microprocessor and to
upload to the microprocessor the prescribed tension settings. This
can simply plug into the keypad device. The use of such an
additional interface device enables an interactive brace monitoring
system which can empirically derive the optimum usage of the brace.
The data downloaded can include a complete hour by hour history of
the use of that brace, along with the associated tension. The
various connections such as between the microprocessor in the brace
and the keypad device, between the additional interface device and
the small peripheral electronic device, and between the
microprocessor in the brace and the additional interface device may
be a direct RF link, or capacitive, inductive or optical
non-electrical (i.e. IR link) connection. It is simply required
that the data be transferrable.
Additionally, the microprocessor can be adapted to continuously or
periodically sense the tension of the brace. Periodic sensing can
be accomplished by momentarily turning the motor on. The motor is
turned on only to check the tension vis-a-vis its current
consumption. This can be accomplished very quickly without
tightening or loosening the brace. Since the microprocessor has
available the information of which key was last pressed to set the
tension, by periodically checking the motor current
consumption/brace tension and comparing it with what it should be
in accordance with the last key pressed, it is possible for the
microprocessor to determine if the brace has been taken off. That
is, if a patient takes the brace off in the fully tightened
condition (which is possible since the brace is held in the front
by hook-and-loop fasteners), and no loosening of the cable occurs,
it will be impossible for the patient to retighten the brace after
putting it back on since the cable has been extensively spooled up.
The microprocessor would sense this by determining the that the
last setting was for a particular tension setting and now that the
brace is off of the patient, there is no tension on the cable. When
the microprocessor senses that the brace has been taken off, it can
unspool the cable so that the brace is automatically ready to be
put back on. In such an embodiment, a spring mechanism is added
between the two plates and the pulley mountings as the means for
loosening the tension setting and unspooling the cable as shown in
FIG. 4. The spring mechanism can comprise a pair of piano wire
springs 36 engaged in spring brackets 38 and biassing the plates 13
away from each other. It is preferable that the microprocessor poll
the current setting and compare it to the last setting desired (by
memory of the last key pressed) every 15 seconds. Of course, the
timing of the polling can be set to any value desired.
Continuous sensing of the tension level is most desired and with
continuous or at least short interval periodic sensing, continuous
or semi-continuous adjusting of the tension can be obtained. In
this manner, automatic control of the brace can be obtained. The
patient can then have the same level of comfort and compliance with
the tension required without any additional input.
Although the invention has been described in conjunction with the
foregoing specific embodiment, many alternatives, variations, and
modifications will be apparent to those of ordinary skill in the
art. Those alternatives, variations, and modifications are intended
to fall within the scope of the following appended claims.
* * * * *