Note: Descriptions are shown in the official language in which they were submitted.
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APPARATUS FOR ULTRASONIC BONE TREATMENT
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for therapeutically treating
injuries using ultrasound. More particularly, the present invention relates to
an apparatus
which utilizes a portable ergonomically constructed signal generator and an
ergonomically
constructed transducer for treating bone injuries or a variety of
musculoskeletal injuries
and/or problems.
2. Description of the Related Art
The use of ultrasound to therapeutically treat and evaluate bone injuries
is known. Impinging ultrasonic pulses having appropriate parameters, e.g.,
frequency, pulse
repetition, and amplitude, for suitable periods of time and at a proper
external location
adjacent to a bone injury has been determined to accelerate the natural
healing of, for
example, bone breaks and fractures. For patients with reduced healing
capacity, such as
elderly persons with osteoporosis, ultrasonic therapy may promote healing of
bone injuries
that would otherwise require prosthetic replacement or leave the patient
permanently
disabled.
U.S. Patent No. 4,530,360 to Duarte describes a basic non-invasive
therapeutic technique and apparatus for applying ultrasonic pulses from an
operative surface
placed on the skin at a location adjacent a bone injury. The applicator
described in the '360
patent has a plastic tube which serves as a grip for the operator, an RF plug
attached to the
plastic tube for connection to an RF source, and internal cabling connected to
an ultrasonic
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transducer. To apply the ultrasound pulses during treatment an operator must
manually hold
the applicator in place until the treatment is complete. As a result, the
patient is, in effect,
immobilized during treatment. The longer the treatment period, the more the
patient is
inconvenienced. The '360 patent also describes a range of RF signals for
creating the
ultrasound, ultrasound power density levels, a range of duration for each
ultrasonic pulse,
and a range of ultrasonic pulse frequencies.
U.S. Patent No. 5,003,965 to Talish et al. relates to an ultrasonic body
treatment system having a body-applicator unit connected to a remote control
unit by
sheathed fiber optic lines. The signals controlling the duration of ultrasonic
pulses and the
pulse repetition frequency are generated apart from the body-applicator unit.
Talish et al.
also describes a mounting fixture for attaching the body-applicator unit to a
patient so that
the operative surface is adjacent the skin location.
While the systems described in these patents relate to therapeutic
methods and apparatus for ultrasonically treating injured bone, they do not
disclose
ergonomically configured signal generators and transducers which permit
patient mobility
during treatment. Moreover, such systems do not describe techniques for
positioning the
transducer at the approximate external skin location of the injury to optimize
the ultrasonic
therapy received.
Therefore, a need exists for apparatus which optimize healing while
maintaining patient mobility. Also a need exists for an apparatus for
determining an external
location on the patient's body corresponding to the location of an internal
bone injury.
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SUMMARY OF THE INVENTION
The ultrasonic treatment apparatus of the present invention is used for
therapeutically treating injuries using ultrasound. The apparatus includes an
ergonomically
constructed ultrasonic transducer treatment head module with an integral
signal generator
which provides excitation signals for an ultrasonic transducer within the
module. The
portable main operating unit is constructed to fit within a pouch worn by the
patient and
provides treatment timing control circuitry as well as monitoring circuitry
for the proper
attachment and operation of the transducer assembly. In operation, the module
is positioned
adjacent the area of the injury and excited for a predetermined period of
time. To ensure
that the transducer treatment head module is properly positioned, a safety
interlock is
provided to insure compliance with the treatment protocol and to prevent
inadvertent
excitation of the transducer assembly.
Preferably, the main operating unit has an internal power source for
powering the signal generator circuitry in the transducer treatment head
module, a display
coupled to said signal generator circuitry to display treatment sequence data,
a keypad
coupled to said signal generator circuitry to permit user operation and/or
entry of data, said
signal generator circuitry including a processor, means for generating a
pulsed control signal,
and a switch coupled to said processor for regulating said pulsed control
signal. A
communication interface may be connected between a communication port and the
processor
to provide a communication link between the ultrasonic signal generator and an
external
computer or modem. Preferably, the communication interface is a serial
communication
interface, however, a parallel interface is also contemplated. An alarm is
provided to
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indicate to the user that the treatment time has expired. The alarm is coupled
to the
processor such that when ultrasonic treatment is completed the processor
activates the alarm
and terminates ultrasound generation.
To ensure that the transducer treatment head module is properly
positioned prior to exciting the ultrasonic transducer, a safety interlock
mechanism is
provided. The transducer treatment head module is configured to interfit with
a fixture
positioned adjacent the injury. The fixture has an aperture configured to
receive a portion of
the ultrasonic transducer treatment head module. At least two bayonet lugs
connected to the
fixture and extending into the aperture, are electrically connected to form a
conductive path
therebetween. In addition, the ultrasonic transducer treatment head module
includes at least
two slotted lugs having at least a portion thereof extending from an outer
surface of the
module. The slotted lugs are configured to engage at least two bayonet lugs
and are
fabricated from conductive plastic such that when the slotted lugs engage the
bayonet lugs a
conductive path is formed between the slotted lugs. In this configuration, the
processor
sends a safety interlock signal to the transducer treatment head module along
one conductor
and the conductive path between slotted lugs returns the safety interlock
signal to the
processor along another conductor. When the processor receives the return
safety interlock
signal, the transducer can now be excited. This feature insures that the
patient correctly
complies with the ultrasound protocol and that the actual treatment is
accurately recorded.
The present invention also provides a kit for ultrasonically treating
injuries while maintaining patient mobility. The kit includes an ultrasonic
transducer
treatment head module, a fixture configured to be worn by a patient adjacent
the injury and
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configured to receive at least a portion of the ultrasonic transducer
treatment head module,
an integrated ultrasonic signal generator located in the ultrasonic transducer
treatment head
module, a main operating unit (MOU) or controller and a pouch constructed to
receive the
MOU. Preferably, the pouch has a belt and a shoulder strap which can be
releasably secured
to a patient during treatment thereby providing patient mobility.
It is a further feature of the present invention that a single or a plurality
of transducer treatment head modules can be attached to a single MOU and be
selectively
controlled thereby.
A method for ultrasonically treating musculoskeletal injuries and
surface injuries such as, for example, open wounds, burns and venous ulcers,
while
maintaining patient mobility is also provided. Initially, the location of the
injury is
determined. Once the location of the injury is ascertained, a fixture is
affixed to the patient
adjacent the location. Preferably, the fixture is configured to receive at
least a portion of an
ultrasonic transducer assembly which is releasably secured to the fixture. A
pouch having
the MOU therein is releasably secured to the patient and is connected to the
transducer
treatment head module. The signal generator in the transducer housing is then
activated so
as to excite an ultrasonic transducer to impinge ultrasonic waves against the
injury. To
permit patient mobility during treatment, the MOU has an internal power
source.
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BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention are described below with
reference to the drawings, which are described as follows:
Fig. 1 is a perspective view of a portable ultrasonic treatment apparatus
according to the present invention, illustrating a main operating unit or
controller and an
ultrasonic transducer treatment head module;
Fig. 2 is a perspective view with parts separated of the main operating
unit and transducer head module of Fig. 1 and a pouch shoulder strap and belt
for patient
mobility during treatment;
Fig. 3 is a perspective view of a patient wearing the portable treatment
apparatus according to the present invention during treatment;
Fig. 4 is an exploded view of the main operating unit of Fig. 1;
Fig. 5 is a block diagram of the circuitry for the main operating unit of
Fig. 1;
-15 Fig. 6 is a block diagram of one embodiment of the circuitry for the
ultrasonic transducer assembly;
Fig. 6A is a block diagram of an alternative embodiment of the
circuitry for the ultrasonic transducer assembly;
Fig. 7 is a perspective view of a locating ring and strap for locating
bone injuries;
Fig. 8 is a perspective view of the locating ring of Fig. 7 affixed to a
patient wearing a cast and illustrating a mark to define the location of a
bone injury;
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Fig. 9 is a perspective view of a template centrally located over the
mark;
Fig. 10 is a perspective view with parts separated of the patient's cast
with a removed section and a fixture for retaining and aligning the ultrasonic
transducer
assembly of Fig. 1;
Fig. 11 is a perspective view of the fixture being secured to the cast at
the removed section;
Fig. 12 is a perspective view with parts separated of the cast, the
fixture and a cap for the fixture; and
Fig. 13 is a perspective view with parts separated, illustrating the
ultrasonic transducer assembly aligned for releasable attachment to the
fixture.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The ultrasonic treatment apparatus of the present invention is used for
therapeutically treating injuries using ultrasound. Although shown here for
the treatment of
musculoskeletal injuries, other injuries including venous ulcers are also
contemplated. The
apparatus includes an ergonomically constructed ultrasonic transducer assembly
partially
fabricated with a conductive plastic material. The apparatus also utilizes a
portable,
ergonomically constructed main operating unit (MOU) which provides control
signals for the
ultrasonic transducer treatment head module. The portable MOU is constructed
to fit within
a pouch worn by the patient. In operation, the transducer treatment head
module is
positioned adjacent the injured area and excited for a predetermined period of
time. To
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ensure that the transducer treatment head module is properly positioned, a
safety interlock is
provided to prevent inadvertent excitation of the transducer assembly and to
insure patient
compliance.
Turning to the figures, in particular Fig. 1, the portable ultrasonic
treatment apparatus 10 of the present invention is shown. The ultrasonic
treatment apparatus
includes an MOU 12 and an ultrasonic transducer treatment head module 14
coupled to
the MOU 12 by cable 16. The MOU 12 is ergonomically configured and constructed
to fit
with a pouch 18 which is worn by the patient using belt 19 and shoulder strap
9, as shown in
Figs. 2 and 3. Cable 16 is preferably a multi-conductor cable capable of
transmitting
10 relatively low frequency or optical signals, as well as digital signals.
Cable 16 may include
coaxial cable or other type of suitable shielded cable. Alternatively, cable
16 may include
fiber optic cable for transmitting optical signals.
Referring to Fig. 4, MOU 12 includes a housing 20 which is typically
constructed in two half-sections joined together by screws, ultrasonic welds
or adhesives. A
printed circuit board 22 is positioned within the housing 20 and coupled to
display assembly
24 via cable 26. Display assembly 24 includes mounting board 28, display 30
and a keypad
31, shown in Fig. 1. Display 30 may be, for example, a liquid crystal type
display or an
LED type display suitable for displaying text and numerals. Battery holder 32
is connected
to printed circuit board 22 for portable operation of the real time clock and
the ultrasonic
treatment head module of the present invention. In addition, a suitable
battery, such as a
bank of three (3) lithium batteries is positioned in the battery compartment.
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Communication port 34 is affixed to printed circuit board 22 and
accessible through channel 36 in housing 20. Communication port 34 is coupled
to signal
generator circuitry 38 on printed circuit board 22 and provides a
communication link, e.g.,
for serial communications, between the signal generator 12 and an external
computer. In this
configuration, a physician can download information, such as the number, date,
time of day,
and/or duration of actual treatments initiated by the patient, stored within
signal generator
circuitry 38.
Fig. 5 illustrates a block diagram of the signal generator circuitry 38
within the signal generator 12 which generates and controls the pulses
transferred to the
ultrasonic transducer assembly 14. Preferably, signal generator circuitry 38
includes a
processor 44 having memory 43 (e.g., RAM and ROM) and stored programs (e.g.,
system
and application) for controlling the operation of the processor, as well as
the transducer
treatment head module 14. Processor 44 is coupled to display 30 and keypad 31
and is
configured to receive data from the keypad 31 and to transfer data to the
display 30.
Processor 44 may include a microprocessor, such as the Intel 80/x86 family of
microprocessors, or processor 44 may be a microcontroller having internal
memory.
Communication interface 35 is connected between communication port 34 and
processor 44
and is provided to communicate with, for example, an external computer.
Communication
interface 35 may be a serial interface, such as an RS-232 interface, a
parallel interface, or a
modem. .
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Processor 44 is also utilized to control the treatment sequence, i.e., the
start time and the stop time of the ultrasonic treatment. The processor may be
pre-
programmed for treatment times and the user (e.g. the physician or patient)
selects one of the
treatment times via keypad 31, or the processor may be programmed by the user
via keypad
31 to set the start and stop sequence. Typical treatment times may range
between 1 and 55
minutes, although treatments in the order of 10-20 minutes are typical. When
the treatment
time is activated, processor 44 closes switch 60 which permits the modulated
signal to pass
to cable 16. When the treatment time expires, switch 60 is opened and the
modulated signal
is inhibited from passing to cable 16. In addition, when the treatment time
expires,
processor 44 may send an alarm signal to alarm 62 which activates.
Referring to Fig. 6, a block diagram of one embodiment of the
transducer treatment head module circuitry is shown. The transducer treatment
head module
circuitry includes a receiver 66 which receives the signals transferred by
signal generator 12
via cable 16. Receiver 66 is connected to transducer driver 67 which excites
transducer 68.
An alternative embodiment of the transducer treatment head module circuitry is
shown in
Fig. 6A. In this embodiment, the transducer treatment head module 14 includes
an internal
battery 69 which supplies power to the internal components of the transducer
treatment head
module. For example, battery 69 supplies power to signal monitoring circuit 70
and signal
driver 71. The signal monitoring circuit 70 provides, preferably, a digital
output signal 72
which represents the waveform characteristics of the output of transducer
driver 67. Such
characteristics may include, for example, the frequency, pulse repetition
frequency, the pulse
width and the average output power of the signal driving transducer 68. The
output signal
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72 of signal monitoring circuit 70 is transferred to signal generator 12 via
driver 71 and
cable 16. Fixture interlock 73, which may include switches on the outer
surface of the
transducer treatment head module, provides power to the internal components of
the
transducer treatment head module 14 so as to ensure that the transducer
treatment head
module 14 is properly positioned before the transducer is excited. A more
detailed
description of this alternative embodiment is described in U.S. Patent No.
5,003,965.
Although shown herein with a single transducer treatment head module,
the present invention also envisions a plurality of modules for use with a
single MOU.
Referring now to Fig. 7, a locating ring 80 for determining the location
of injured bone is shown. The locating ring 80 includes a strap 82 for
releasably securing
the ring to a patient. The strap 82 preferably has two sections 84 and 86
which permit quick
fastening and unfastening of the ring 80 on and off the patient. The ring 80
is constructed of
material that may be seen with a chosen medical visualizing system. Thus, if X-
rays are
used, the ring 80 is at least partially opaque to X-radiation. If infra-red
radiation is used, the
ring 80 is at least partially opaque to infra-red radiation, and, if magnetic
resonance imaging
is used, the ring 80 is at least partially paramagnetic. However, the other
materials may be
used for the ring which permits detection by medical visualizing or imaging
systems.
The dimensions of the ring 80 are typically a function of the size of the
patient, the estimated size and location of the injury, and the type of
visualizing system used.
For example, to determine the location of a bone fracture in an average human
limb, e.g.,
the ulna'or radius, and using an X-ray imaging system, the diameter of the
ring may
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nominally be 1.5 inches. In this example, the ring may be a rigid torus of
metallic material
of cross-sectional diameter nominally .2 inches. As another example, if the
visualization
system utilized is an ultrasonic imaging system, the ring 80 may be
substantially flexible and
planar, so that it may contour to a surface it is placed adjacent to, thereby
allowing the
scanning or imaging transducer to be moved across the surface and the ring.
As noted, the strap 82 has two sections 84 and 86, each section has one
end fastened to the ring 80. The two sections 84 and 86, preferably, have hook
and loop
type fastening assembly, such as VELCRO , so that they may be fastened
together and
quickly unfastened. Other quick release fastening techniques are also
contemplated.
Figs. 8 through 12 illustrate locating an injured bone, affixing a fixture
configured to maintain the transducer treatment head module adjacent the area
of the injured
bone, and connecting the ultrasonic transducer assembly to the fixture for
treating the injured
bone. Initially, the locator ring 80 is positioned on a cast 88 on, for
example, a patient's
arm, at a location corresponding to the estimated or approximated location of
the injury.
This initial position is a preliminary approximation of the external location
of the bone
injury, and may be based on previously taken X-rays, a physician's diagnosis
or the patient's
recall of the point of injury.
An external image, e.g., an X-ray, of the fractured region is taken to
include the locating ring 80. Although the initial position of the locating
ring 80 with respect
to the bone injury is a preliminary approximation, in many instances the
initial placement
will be sufficiently accurate so that the X-ray will depict the bone injury
framed by the ring
80. The resulting X-ray image indicates the position of the bone injury
relative to the
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locating ring 80. The X-rays are used as a guide to locate and mark 90 the
corresponding
point on the cast relative to the actual locating ring 80. The mark 90 gives
an approximate
external location on the cast of the bone injury. If greater accuracy is
required, the ring 80
may be centered about the mark 90, another X-ray is taken, and a new mark (not
shown) is
made on the cast based on the location of the bone fracture relative to the
ring on the X-ray.
Successive iterations of repositioning the locating ring 80 and X-raying the
site will yield
even greater accuracy.
As shown in Figs. 9 and 10, a rectangular template 92 is pressed
against the cast 88 and centered on the mark 90 of the external location on
the cast 88 of the
bone fracture. The outline of the inner edges of the template opening is
traced on the cast
88, and the traced portion of the cast is removed so that the opening 9_4 in
the cast 88
exposes the slan, as shown in Fig. 10. The opening 9: in the cast 88 receives
a felt pad 96
having a thickness approximately the same as the thickness of the cast. The
felt pad 96 also
has a cylindrical bore that receives a cylindrical felt pad 98. Felt pad 96 is
provided to
support fixture 102 and to maintain pressure against the skin which helps
prevent window
edema (swelling) and is substantially equivalent to the pressure exerted by
the cast 88 against
the skin and is described in more detail below.
Preferably, the template 92, and consequently the opening 94 in the
cast 88, is smaller than the flange of a fixture 102 for retaining and
aligning the ultrasonic
transducer assembly 14, so that the flange engages the cast surface
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surrounding the opening 94 when the fixture is placed over the opening 9Y. The
fixture 102
also has a circular aperture 104 and bayonet locking lugs 106. Aperture 104
has
substantially the same diameter as the cylindrical felt pad 98.
Fig. 11 shows the fixture 102 positioned over the opening 94 in the
cast 88 and the felt pad 96 so that the aperture 104 and the cylindrical felt
pad 98 are
coaxially aligned. The fixture 102 partially compresses the felt pad 96, shown
in Fig. 10,
against the skin as flange of fixture 102, shown in Fig. 8, engages the cast
88, thereby
approximating the pressure of the removed portion of the cast where the felt
pad engages the
slrin.
Referring to Fig. 12, a cap 108 for the fixture 102 is shown. The cap
108 is provided to maintain pressure on the body tissue exposed in fixture 102
when the
ultrasonic treatment is completed. The cap 108 has a cylindrical portion 110
that extends
into the aperture 104 of the fixture 102. The cap 108 has slotted lugs 112 on
the cylindrical
portion 110 that engage the bayonet lugs 106 in the fixture 102. The
cylindrical felt pad 98
is positioned in the aperture 10N, and the cylindrical portion 110 is inserted
into the aperture
104 with the slotted lugs 112 offset from the bayonet lugs 106. The cap 108 is
pressed
against the cylindrical felt pad 98 until the pressure exerted by the cap 108
and cylindrical
felt pad 98 against the sldn approximates the pressure exerted by the cast 88
against the slan.
(The cylindrical felt pad 98 may also be comprised of substantially planar
circular layers that
may be removed one layer at a time in order to adjust the thickness of the
felt pad and the
resulting pressure against the skin.) This pressure helps to inhibit window
edemas. The cap
108 is then rotated so that its slotted lugs 112 engage the bayonet lugs 106.
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Fig. 13 is a perspective view illustrating the alignment of the ultrasonic
transducer treatment head module 14 with the fixture 102 for ultrasonic
treatment of the
injured bone. The transducer treatment head module projection 114 has slotted
lugs 116 that
engage the bayonet lugs 106 in the fixture 102. With the cap 108 and
cylindrical felt pad 98,
shown in Fig. 10, removed, the projection 114 fits into the aperture 104 of
the fixture 102
and the bore of the felt pad 96, and is inserted with the slotted lugs 116
offset from the
bayonet lugs 106. The operative surface 118 of the transducer treatment head
module 14 is
pressed adjacent the skin and the transducer treatment head module 14 is then
rotated so that
its slotted lugs 116 engage the bayonet lugs 106. The ultrasonic treatment
then commences.
Referring again to Figs. 5 and 6, to prevent inadvertent excitation of
transducer treatment head module 14 and to insure compliance with treatment
protocol,
slotted lugs 116 are preferably fabricated from a conductive plastic and the
bayonet lugs 106
in fixture 102 are electrically connected, such that when the slotted lugs 116
engage the
bayonet lugs 106 an electrical path is completed between at least two of the
slotted lugs 116.
Suitable conductive plastics which may be utilized include conductive ABS
plastics with
either carbon, stainless steel, nickel or aluminum fibers.
Preferably, the operative surface 118 of transducer treatment head
module 14 includes a gel sensing element for confirming the presence of
ultrasonic
conductive material on the operative surface 118. This surface 118 is pre-
coated with a
coupling gel before it is inserted in the fixture 102 and engages the skin.
Alternatively, the
gel may be contained adjacent the operative surface 118 of transducer
treatment head module
14 using a gel sack, gel bladder or like container.
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It will be understood that various modifications can be made to the
various embodiments of the present invention herein disclosed without
departing from its
spirit and scope. For example, various shapes of the pouch and signal
generator are
contemplated, as well as various types of construction materials. Also,
various modifications
may be made in the configuration of the components used to excite the
ultrasonic transducer.
Therefore the above description should not be construed as limiting the
invention but merely
as presenting preferred embodiments of the invention. Those skilled in the art
will envision
other modifications within the scope and spirit of the present invention as
defined by the
claims presented below.
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