U.S. patent application number 13/734170 was filed with the patent office on 2013-05-16 for tissue monitoring surgical retractor system.
This patent application is currently assigned to WARSAW ORTHOPEDIC, INC.. The applicant listed for this patent is Warsaw Orthopedic, Inc.. Invention is credited to Jeff R. Justis, Nikolas F. Kerr, Greg C. Marik, Newton H. Metcalf, Joseph Jude Saladino, Hai H. Trieu, Jusong Xia.
Application Number | 20130123582 13/734170 |
Document ID | / |
Family ID | 44309462 |
Filed Date | 2013-05-16 |
United States Patent
Application |
20130123582 |
Kind Code |
A1 |
Xia; Jusong ; et
al. |
May 16, 2013 |
TISSUE MONITORING SURGICAL RETRACTOR SYSTEM
Abstract
An apparatus for monitoring the characteristics of tissue
adjacent a surgical site and communicating that information to a
health care provider includes a retractor, a sensor, and a
processing system. The sensor is disposed on the retractor and is
configured to measure a parameter indicative of at least one
characteristic of the tissue adjacent the first or the second
blade. The processing system is in communication with the sensor
and configured and arranged to receive information from the sensor
indicative of the measured parameter. It includes a threshold
stored therein indicative of excessive trauma to the tissue and it
is configured in a manner such that it compares the received
information to the stored threshold and communicates information to
the health care provider regarding the comparison.
Inventors: |
Xia; Jusong; (Collierville,
TN) ; Saladino; Joseph Jude; (Memphis, TN) ;
Justis; Jeff R.; (Germantown, TN) ; Metcalf; Newton
H.; (Memphis, TN) ; Marik; Greg C.;
(Collierville, TN) ; Kerr; Nikolas F.;
(Germantown, TN) ; Trieu; Hai H.; (Cordova,
TN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Warsaw Orthopedic, Inc.; |
Warsaw |
IN |
US |
|
|
Assignee: |
WARSAW ORTHOPEDIC, INC.
Warsaw
IN
|
Family ID: |
44309462 |
Appl. No.: |
13/734170 |
Filed: |
January 4, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12695211 |
Jan 28, 2010 |
8376937 |
|
|
13734170 |
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Current U.S.
Class: |
600/202 |
Current CPC
Class: |
A61B 1/32 20130101; A61B
46/17 20160201; A61B 2017/00022 20130101; A61B 2017/00199 20130101;
A61B 2017/00221 20130101; A61B 2017/00119 20130101; A61B 2017/00115
20130101; A61B 17/0206 20130101 |
Class at
Publication: |
600/202 |
International
Class: |
A61B 1/32 20060101
A61B001/32 |
Claims
1-14. (canceled)
15. A sensor system for use on surgical refractor system
comprising: a detector for receiving a signal or stimulus that
creates a signal based on the received signal or stimulus; an
anchor portion shaped to removably attach to a portion of the
surgical retractor system.
16. The sensor system of claim 15, wherein the anchor portion
comprises a sleeve configured to receive a portion of the retractor
therein.
17. The sensor system of claim 15, wherein the anchor portion is a
C-shaped clip configured to clip onto the refractor.
18. The sensor system of claim 15, wherein the anchor portion is a
flexible patch having an adhesive layer therein.
19-20. (canceled)
Description
FIELD OF THE INVENTION
[0001] The present disclosure is directed to a surgical retractor
system. More particularly, the present disclosure is directed to a
retractor system that monitors parameters indicative of the state
of a patient's tissue adjacent a retractor of the retractor
system.
BACKGROUND
[0002] Side effects of anterior cervical decompression and fusion
procedures may include post-operative dysphagia. This condition,
making swallowing difficult or impossible, can be relatively long
lasting, with up to twelve percent of patients with dysphagia
symptoms still having those symptoms a year after surgery. Surgeons
and scientists are researching whether the incidence and recovery
from dysphagia corresponds with the size of the surgical
dissection, the trauma induced by retractors, and the length of the
time the retractors are used to maintain an open surgical site.
[0003] Conventional retractors are placed at a surgical site and
used to retract tissue based solely upon a surgeons preference and
experience. A surgeon conventionally attempts to "feel" when the
retractor applies excessive loading to the tissue. If the loading
links to the incidence of dysphagia, it would be helpful to have a
system for monitoring loading or other parameters indicative of the
state of the tissue.
[0004] The systems and methods disclosed herein address one or more
of the shortcomings of the prior art.
SUMMARY
[0005] These and other aspects, forms, objects, features, and
benefits of the present invention will become apparent from the
following detailed drawings and description.
[0006] The present disclosure is directed to a surgical retractor
system for monitoring the characteristics of tissue adjacent a
surgical site and communicating that information to a health care
provider. The surgical retractor system may include a retractor, a
sensor, and a processing system. The retractor may include a first
blade for interfacing with tissue on a first side of a surgical
site, a second blade for interfacing with tissue on a second side
of the surgical site opposite the first side of the surgical site,
and a body portion supporting the first blade relative to the
second blade. The body portion may be adjustable in situ in a
manner that changes tissue parameters by displacing the first blade
relative to the second blade to displace tissue and provide access
to a surgical site. The sensor is disposed on the retractor and is
configured to measure a parameter indicative of at least one
characteristic of the tissue adjacent the first or the second
blade. The processing system is in communication with the sensor
and configured and arranged to receive information from the sensor
indicative of the measured parameter. The processing system
includes a threshold stored therein indicative of excessive trauma
to the tissue. The processing system is configured in a manner such
that it compares the received information to the stored threshold
and communicates information to the health care provider regarding
the comparison.
[0007] In another aspect, the present disclosure is directed to a
sensor system for use on surgical retractor system. The sensory
system includes a detector for receiving a signal or stimulus that
creates a signal based on the received signal or stimulus and an
anchor portion shaped to removably attach to a portion of the
surgical retractor system. In some aspects, the sensor system is
one of a sleeve configured to receive a portion of the retractor
therein, a C-shaped clip configured to clip onto the retractor, and
a flexible patch having an adhesive layer therein.
[0008] In another aspect, the present disclosure is directed to a
surgical retractor system for monitoring the characteristics of
tissue adjacent a surgical site and communicating that information
to a health care provider. The surgical retractor system may
include a retractor and a tissue parameter detecting system. The
retractor includes a first blade for interfacing with tissue on a
first side of a surgical site, a second blade for interfacing with
tissue on a second side of the surgical site opposite the first
side of the surgical site, and a body portion comprising a first
arm and a second arm and an adjustment element adjustably
connecting the first and second arms. The first and second arms
respectively support the first blade and the second blade. The
adjustment element is adjustable in situ in a manner that changes
tissue parameters by displacing the first blade relative to the
second blade to displace tissue and provide access to a surgical
site. The tissue parameter detecting system is structurally
configured and arranged to measure a parameter indicative of at
least one characteristic of the tissue adjacent the first or the
second blade. The tissue parameter detecting system has a threshold
stored therein indicative of excessive trauma to the tissue. The
tissue parameter detecting system is structurally configured and
arranged in a manner such that it compares the measured information
to the stored threshold and communicates information to the health
care provider regarding the comparison.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The accompanying drawings serve to exemplify some of the
embodiments of this invention.
[0010] FIG. 1 is an illustration of a perspective view of a
surgical retractor of the present disclosure with a sensor for
detecting data indicative of the state of tissue adjacent the
retractor.
[0011] FIG. 2 is an illustration of a top view of two surgical
retractors in a surgical application, one of the surgical
retractors having a sensor thereon and in communication with a
retraction monitor and system in accordance with the disclosure of
FIG. 1.
[0012] FIG. 3 is an illustration of an exemplary retraction monitor
connectable to the sensor in FIGS. 1 and 2.
[0013] FIG. 4 is an illustration of a sensor system in the form of
a sensor sleeve having a built-in sensor in accordance with the
present disclosure.
[0014] FIG. 5 is an illustration of a sensor system in the form of
a clip having a built-in sensor in accordance with the present
disclosure.
[0015] FIG. 6 is an illustration of the sensor system in FIG.
5.
[0016] FIG. 7 is an illustration of a sensor system in the form of
an adhesive patch having a built-in sensor in accordance with the
present disclosure.
[0017] FIG. 8 is an illustration of a perspective view of a
surgical retractor of the present disclosure with a sensor for
detecting data indicative of the state of tissue adjacent the
retractor usable in a wireless environment.
[0018] FIG. 9 is a diagram of an exemplary wireless transmission
system using inductive coupling.
DETAILED DESCRIPTION
[0019] The present disclosure relates generally to the field of
orthopedic surgery, and more particularly to devices, systems and
methods for monitoring tissue displaced by a retractor system. For
the purposes of promoting an understanding of the principles of the
invention, reference will now be made to embodiments or examples
illustrated in the drawings, and specific language will be used to
describe these examples. It will nevertheless be understood that no
limitation of the scope of the invention is thereby intended. Any
alteration and further modifications in the described embodiments,
and any further applications of the principles of the invention as
described herein are contemplated as would normally occur to one
skilled in the art to which the disclosure relates.
[0020] This disclosure is directed to instruments and methods for
performing percutaneous surgery, including spinal surgeries that
include one or more techniques such as laminotomy, laminectomy,
foramenotomy, facetectomy, discectomy, interbody fusion, spinal
nucleus or disc replacement, and implant insertion including
plates, rods, and bone engaging fasteners, for example. A retractor
system, including a retractor, permits a surgeon to perform through
a working channel or passageway through skin and tissue of the
patient. The retractor is adjustable in situ to increase the size
of the working channel to facilitate access to the working space at
the distal end of the retractor while minimizing trauma to tissue
surrounding the retractor. The retractor can be used with any
surgical approach to the spine, including anterior, posterior,
posterior mid-line, lateral, postero-lateral, and/or antero-lateral
approaches, and in other regions besides the spine.
[0021] FIG. 1 shows an exemplary a retractor system 100, including
a retractor 102 and a processing system 103 that, in this
embodiment, includes a monitor 104 and a console, such as a
computer system 106. The retractor 102 includes a variable width
main body tube 108 formed of a first blade 110 and a second blade
112. It also includes a first arm 114 and a second arm 116
extending from the main body tube 108. These are adjustably
connected to each other at a proximal end by an adjustment element
118. The adjustment element 118 adjusts the distance between the
first and second arms 114, 116, and likewise, adjusts the distance
between the first and second blades 110, 112.
[0022] In this embodiment, the blades 110, 112 have an arcuate
cross section with a concave inner surface and a convex outer
surface. In other embodiments, the blades have other configurations
such as flat, curved, or other geometries. The first blade 110 has
a distal end 120 and an opposite proximal end 122. The second blade
112 has a distal end 124 and an opposite proximal end 126. The
distal ends 120, 124 may be beveled to facilitate insertion,
although non-beveled ends are also contemplated. A working channel
128 is formed between the first and second blades 110, 112. After
insertion into a patient, the working channel 128 is enlarged by
spreading the first and second blades 110, 112 apart using the
adjustment element 118. In this embodiment, the adjustment element
118 is a rack and pinion assembly, although outer adjustment
elements are contemplated. In some examples, the adjustment element
118 comprises a motor, such as an electric, hydraulic, or pneumatic
motor that spreads apart the first and second blades.
[0023] The first and second blades 110, 112 are respectively
coupled with the first and second arms 114, 116 which are engaged
with adjustment element 118. It should be appreciated that the
blades 110, 112 may be coupled with the arms 114, 116 in any
suitable arrangement, including dovetail connections, fasteners,
threaded coupling members, clamping members, snap rings,
compression bands, straps, ball-detent mechanisms, releasably
interlocking cams or tabs, welding, fusing, and/or adhering, just
to name a few possibilities. In some embodiments, the blades 110,
112 are integrally formed with the arms 114, 116. Still further,
the blades 110, 112 may be removably coupled with the arms 114,
116, and alternative retractor blades may be chosen from a
plurality of retractor blades to replace retractor blades 110, 112
to better suit a particular application in which the retractor 102
may be used. In addition, it should be noted that alternative
embodiments use more than two plates, and in further alterative
embodiments, a single blade may be used.
[0024] In use, after insertion into the patient, the working
channel 128 can be enlarged by separating first retractor blade 110
and second retractor blade 112. Separation of the retractor blades
110, 112 increases the size of working channel 128. However, as
with any invasive surgery, this separation applies some level of
stress and trauma to the tissue about the surgery site.
[0025] FIG. 2 is a top view showing two retractors 140, 142,
respectively, in use at a surgical site to maintain or retract
tissue in a position providing surgical access according to an
exemplary aspect of the present disclosure. Here, the retractors
140, 142 are similar in many respects to the retractor 102
described above, and for efficiency, will not be re-described in
great detail. It is sufficient to note that the retractors 140, 142
each include first and second blades, arms, and an adjustment
element that controls the separation between the arms and
blades.
[0026] To quantify the level of stress and trauma to the tissue at
the surgical site, each of the retractor 102 in FIG. 1 and the
retractor 140 in FIG. 2 includes a sensor 150 associated therewith.
The sensor 150 provides information indicative of one or more
parameters of the loading stress, trauma, status, or other
parameter of the tissue at the surgical site. For example, the
sensor 150 may provide information including mechanical, thermal,
chemical fluidity (such as pressure, time, heat, blood flow, lactid
acid build-up, or other parameters) determined to be useful in a
surgical setting. In the embodiment in FIG. 1, the sensor 150 is
disposed upon the blade 110 of the retractor 102. Accordingly, in
addition to sensing the pressure on the blade 110, the sensor may
interface directly with the tissue and may provide information
relating to either the state of the retractor or directly measure
parameters of the tissue. In some examples, a sensor 150 may be
used on each blade. In other examples, the sensor 150 may be used
only on a single blade. The blade may be the medial blade,
responsible for retracting the midline structures from the anterior
aspect of the spine. For example only, the sensor 150 may be a
strain sensor, a thermocouple, a flow meter such as a Transonic
VLF-21 Laser Doppler Flowmeter, other sensors, or a plurality of
sensors arranged in a manner known in the art.
[0027] In the embodiment in FIG. 2, the sensor 150 is disposed upon
a retractor arm of the retractor 142. In this embodiment, the
sensor 150 is a strain sensor arranged to sense the arm strain
indicative of pressure applied to the retractor blade 110 by
patient tissue during use.
[0028] In either case, the monitor 104 is structurally configured
to receive information from the sensor 150. In the embodiment
shown, the monitor 104 is connected to the sensor 150 via a wired
connection 134. Signals transmitted over the wired connection 134
provide information that may be filtered or processed to identify
information gathered by the sensor 150.
[0029] FIG. 3 shows an exemplary monitor 104. It includes both a
display portion 160 and an input portion 162. The display portion
includes a visual indicator 164 labeled "Normal," a visual
indicator 166 labeled "Alarm," and a visual indicator 168 labeled
"Blade Size." The display portion 160 provides real time feedback
based on information received from the sensor indicative of the
level of tissue trauma. For example, the monitor 104 may indicate
that the received information indicates that the tissue at the
surgical site is subject to trauma above or below a pre-established
threshold. In some embodiments, the monitor 104 is configured to be
operable with different blade sizes, and the threshold value may be
different based on the retractor blade size.
[0030] When the Normal visual indicator 164 is active, the sensor
information is indicative of trauma levels below a preset
threshold. In some instances the threshold value level is
configured to automatically adjust over time. For example, the
monitor 104 may be programmed so that the threshold decreases over
a surgical period, such that even a lower level of trauma is not
maintained too long.
[0031] When the Alarm visual indicator 166 is active, the sensor
information is indicative of trauma levels above a preset
threshold. This alerts the surgeon to reduce the pressure on the
tissue at least for a period of time. In addition to a visual Alarm
indicator, the monitor includes an audible indictor. Further, some
embodiments include a tactile indicator where the monitor 104
vibrates as an alarm indicator. Also, in some embodiments, the
visual indicators have color-based lighting schemes, for example,
with green indicating that measured parameters are below a
threshold, red indicating that measured parameters are above a
threshold, and flashing red or yellow indicating that tissue should
be relaxed for a period of time. Other alarm schemes are also
contemplated. Accordingly, the surgeon may be alerted to
over-trauma levels in any of multiple ways.
[0032] The input portion 162 of the monitor 104 includes a power
selector 170, a blade selector 172, a record selector 174, and a
mute selector 176. These are shown as buttons, but may be icons on
a touch screen, or may be selectable by a mouse, keyboard, or other
input device. The record selector 174 turns on a recorder that
records the feedback from the sensor 150. The recorder may be a
microcomputer or chip capable of receiving, recording, or
processing information communicated by the sensor 150 on the
retractor 102.
[0033] In some examples, the monitor 104 is configured to monitor
retraction force/pressure and force/pressure vs. time. In other
examples the monitor is configured to monitor temperature, chemical
fluidity (e.g., pressure, time, heat, blood flow, lactid acid
build-up) or other parameters.
[0034] In some embodiments, the monitor 104 is also a safety
mechanism. For example, when a detected sensor signal exceeds a
pre-established threshold, then in addition to the alarm system
being activated as described above, a safety mechanism may be
activated. This may include automatically controlling the retractor
to relieve pressure on the tissue. This may cooperate with
retractors having an automatic distraction control as is disclosed
in U.S. Patent Publication No. 2009/0306480, filed Jun. 6, 2008,
incorporated herein by reference. The automatic control may provide
a gradual reduction in pressure by distracting the blades, may
provide oscillation, or massaging vibration, or other safety
mechanisms that provide relief to the tissue. As the pressure
decreases, the alarm function on the monitor 104 may likewise
adjust, such as changing from a solid light indicator to a flashing
indicator, for example.
[0035] In the embodiment shown, the monitor 104 connects to the
computer system 106. This may be a personal computer or other
computer system, and may include its own input devices, such as a
keyboard, mouse, and other standard input devices. The computer
system 106 may further process the sensor signal and may provide
graphs or additional information indicative of the information
detected by the sensor. In some embodiments, the computer system
106 is component that records the detected information when the
record input is selected on the monitor 104. In some embodiments
the monitor 104 and computer system 106 are combined into a single
unit that monitors the tissue. In other embodiments, the computer
and the monitor are used independently of each other, without being
attached together.
[0036] FIGS. 4-7 disclose sensor systems for removably attaching
the sensor 150 to the retractor 102. Accordingly, in some
embodiments, the sensor system may be removed and discarded after
use and before the retractor is sterilized.
[0037] FIG. 4 discloses a sensor system 200 including an anchor
portion for attachment to the retractor 102 and the sensor 150. In
this embodiment, the anchor portion is a sleeve 202. The sleeve 202
includes at least one end with an opening 204 for receiving at
least part of the retractor 102. Accordingly, the sleeve 202 may be
sock-like, with a single open end, or may be tube-like, with two
open ends. In this embodiment, the sleeve 202 is sized and shaped
to receive at least a part of the first blade 110. In some
embodiments, it is formed to have a particular shape matching the
retractor 202, while in other embodiments, the sleeve 202 is
configured of a conformable material, such as a fabric, that may
conform to the shape of the retractor 102. The disposable sleeve
202 can be made of any suitable material, including flexible or
elastic polymers, such as polyurethane, silicone, and rubber, among
many others.
[0038] In some embodiments, the sensor 150 is built into or
embedded within the sleeve 202 such that the sensor 150 is applied
against the retractor 102, and configured to measure a particular
parameter of the retractor 102. For example, the sensor 150 may be
configured to measure, for example only, force, displacement,
contact stress, torque deflection, tension, compression, strain,
and pressure on the retractor 102. In other embodiments, the sensor
is associated with the sleeve in a manner that enables it to
measure parameters of the tissue adjacent the sleeve. For example,
the sensor 150 may be configured to measure temperature, pressure,
blood flow, lactid acid build-up, or other parameters. When placed
on the retractor, the sleeve 202 and the sensor 150 are configured
to cooperate with the processing system 103 to record and/or
process the pressure or strain information communicated from the
sensor 150 during the surgery.
[0039] It is worth noting that the more than one disposable sleeve
may be used with the retractor 102 at a single time. For example,
the blades 110, 112 may each by outfitted with a sleeve-type sensor
system 200. Further, each sleeve 202 may include more than one
sensor 150 disposed thereon for measuring more than one parameter.
These may be sensors of the same or different types. As explained
above, the sensors 150 may include one or more of any those that
measure the following data: temperature, force, displacement,
contact stress, torque deflection, tension, compression, pressure,
and strain, among others. The disposable sensors 150 may track,
record, transmit, or store the above data as a function of
time.
[0040] FIG. 5 shows another embodiment of a retractor 102 with a
first arm 114, a second arm 116, and a sensor system 210 for
removable attachment to the retractor. In this embodiment, the
sensor system 210 includes an anchor portion as a flexible C-shaped
clip that snaps onto the retractor. In FIG. 5, the sensor system
210 is attached to the first arm 114, but may be configured to
attach to any suitable portion on the retractor 102. FIG. 6 shows
the sensor system 210 in greater detail. As can be seen, the sensor
system 210 comprises the clip body 212, a sensor 150, and in this
embodiment, a coil 213 for wireless transmission using inductive
coupling, explained further below. Here, the clip body 212 includes
two legs 214, 216 and a side 218 that together form a C-shape. A
lip 220 at the ends of the legs 214, 216 permits the clip body 212
to snap onto the retractor 102, securing it in place. The clip body
212 can be made of any suitable material, including flexible or
elastic polymers, such as polyurethane, silicone, and rubber, among
many others.
[0041] In some embodiments, the sensor 150 is built into or
embedded within the body 212 such that the sensor 150 is applied
against the retractor 102 and configured to measure a particular
parameter of the retractor 102, as explained above. In other
embodiments, the sensor 150 is associated with the clip body 212
and the retractor 102 in a manner that enables it to measure
parameters of the tissue adjacent the clip body, as explained
above. When placed on the retractor, the sleeve 202 and the sensor
150 are configured to cooperate with the processing system 103 to
record and/or process the pressure or strain information
communicated from the sensor 150 during the surgery.
[0042] FIG. 7 shows another sensor system 220 as an adhesive patch.
This sensor system 220 includes an anchor portion for removable
attachment to the retractor 102 in the form of an adhesive layer
222. The adhesive patch includes the adhesive layer 222, a backing
layer 224, and the sensor 150. The adhesive layer 222 may be formed
of any adhesive that securely holds the sensor 150 in place and
that can be removed from the retractor 102 prior to sterilization.
The backing layer 224 may be a flexible woven or non-woven
material. The sensor system 220 may be placed either on the blade
to be contact with tissue or on the retractor arm, out of contact
with the tissue. This sensor system 220 may be removed from a
sterile packet and attached to an appropriate location on the
retractor.
[0043] In all the embodiments in this disclosure, more than one
sensor may be used at the same time in the same region or different
regions of the retractor, for measuring the same parameter or for
measuring different parameters. Accordingly, the sensor systems as
well as directly placed sensors as in FIG. 1, may include a
plurality of sensors 150. As explained above, the sensors 150 may
include one or more of any sensors that measure the following data:
temperature, force, displacement, contact stress, torque
deflection, tension, compression, pressure, and strain, among
others. The disposable sensors 150 may track, record, transmit, or
store the above data as a function of time.
[0044] FIG. 8 shows another embodiment of the of the retractor in
FIG. 2. In this embodiment, instead of employing a wired
communication system, the device employs a wireless communication
between the sensor 130 and the monitor 104. Accordingly, the
information collected by the sensor 130 may be communicated via a
wireless transmission the monitor 104. This wireless communication
may be accomplished via any suitable wireless method, including RF,
Bluetooth, inductive, coupling, transmissions via ultrasound,
microwave, or other ranges and frequencies.
[0045] FIG. 9 discloses one example of a wireless system 300 for
communicating between the sensor 150 and the monitor 104. This
embodiment uses inductive coupling to wirelessly power the sensor
and retrieve data. Here, the sensor or sensor system comprises the
sensor 150, circuitry 302, and a transmission coil 304. The monitor
104 comprises a reader coil 306 as an inductive antenna. The reader
coil 306 need not be contained within the monitor housing, but may
extend from the housing for placement somewhere adjacent the
surgical site. The reader coil 306 and the transmission coil 304
cooperate by transfer data and energy. In use, the reader coil 306
supplies energy to the transmission coil 304. This in turn powers
the circuit 302 and retrieves data from the sensor 150. This
information maybe processed at the sensor or may be wirelessly
transmitted from the transmission coil 304. Once received, the
information may be processed as described above.
[0046] Wireless communications other than those described above
also may be used. For example, the sensor 150 may be associated
with a power source and transmitter disposed on the retractor 102.
Accordingly, the range of the wireless transmitted signals may be
greater than when inductive coupling is used. In some instances,
the sensor 150 may be a passive sensor, while in other embodiments,
the sensor 150 may be an active sensor. In addition, the sensor may
be either a one way or two way sensor, and may be internally
powered or externally powered. In some aspects, the sensors are
connected to an antenna for improved wireless signaling. As
described above, the sensor 150 may be either disposable or
non-disposable. All the features described above are also relevant
when wireless technology is used to transmit and process
information. For example, even using wireless technology, the
monitor 104 or computer system 106 may, record and interpret
data.
[0047] In use, a surgeon makes an incision into a patient. If a
sensor is not attached to the retractor, the surgeon may attach the
sensor. As described above, this may be accomplished by attaching a
removable and flexible sleeve including the sensor about a portion
of the retractor, attaching a clip including the sensor, or
adhering an adhesive patch including the sensor. Other attachment
methods are contemplated.
[0048] With the retractor prepared, the surgeon inserts the
retractor blades into the incision. In some examples, the blades
are formed to create a working channel between them. In other
examples, the adjustment element spreads apart the arms and blades,
and the spreading blades spread the tissue, creating a working
channel. During this spreading step and/or with the blades in place
against the tissue, the sensor detects changes in measurable
parameters indicative of the state of the tissue adjacent the
blades. As described above, the measurable parameter may be strain
on the blades or arm, direct force on the blades, pressure,
temperature, or any of the other listed or unlisted parameters.
[0049] The monitor receives signals from the sensor with
information indicative of the measured parameter. In some
embodiments, the monitor stores a threshold value for the retractor
that coincides with a value beyond which there is an increased risk
of tissue damage. The monitor may compare the received information
with the stored threshold. If the received information exceeds the
threshold, the monitor may give a warning as discussed above. For
example, the warning may be activated with a pressure greater than
100 mmHg has been sustained for more than 15 minutes or when a
pressure greater than 50 mmHg has been sustained for more than 30
minutes.
[0050] The monitor or an associated computer system also may record
the information and display graphs or charts indicative of the
measured parameters of the status of the tissue.
[0051] While the present invention has been illustrated by the
above description of embodiments, and while the embodiments have
been described in some detail, it is not the intention of the
applicant to restrict or in any way limit the scope of the
invention to such detail. Additional advantages and modifications
will readily appear to those skilled in the art. Therefore, the
invention in its broader aspects is not limited to the specific
details, representative apparatus and methods, and illustrative
examples shown and described. Accordingly, departures may be made
from such details without departing from the spirit or scope of the
applicant's general or inventive concept. It is understood that all
spatial references, such as "longitudinal axis," "horizontal,"
"vertical," "top," "upper," "lower," "bottom," "left," and "right,"
are for illustrative purposes only and can be varied within the
scope of the disclosure.
* * * * *