U.S. patent application number 10/692707 was filed with the patent office on 2004-05-13 for method of making a pin with multiple in-line contacts.
Invention is credited to Chinn, Kenny K., Goldman, Stephen L., Jang, Grace Ying Yang, Lauro, B. Reno, Sandford, Donald L..
Application Number | 20040093051 10/692707 |
Document ID | / |
Family ID | 26897509 |
Filed Date | 2004-05-13 |
United States Patent
Application |
20040093051 |
Kind Code |
A1 |
Chinn, Kenny K. ; et
al. |
May 13, 2004 |
Method of making a pin with multiple in-line contacts
Abstract
A tool-less connector with multiple contacts and a compact
design is provided. Therefore, a connector that is normally
tunneled through body tissue will now require only a minimally
invasive subcutaneous tunnel, which should reduce tissue healing
time, patient discomfort, and risk of infection. In addition,
providing additional contacts allows enhanced stimulation
protocols. One embodiment of the present invention provides a
connector pin containing multiple in-line contacts. Each "line"
consists of a row of independent contacts arranged in a linear
array running along the long axis of the pin. In other embodiments
of the invention, the mating receptacle of the connector allows for
multiple contacts while minimizing the space required for the
increased number of contacts. Additional embodiments provide
features that, for instance, prevent the contacts on the connector
pin to touch the contacts in the receptacle until all contacts are
appropriately aligned.
Inventors: |
Chinn, Kenny K.; (Castaic,
CA) ; Jang, Grace Ying Yang; (Calabasas, CA) ;
Goldman, Stephen L.; (Stevenson Ranch, CA) ;
Sandford, Donald L.; (Cooper City, FL) ; Lauro, B.
Reno; (Santa Clarita, CA) |
Correspondence
Address: |
ADVANCED BIONICS CORPORATION
12740 SAN FERNANDO ROAD
SYLMAR
CA
91342
US
|
Family ID: |
26897509 |
Appl. No.: |
10/692707 |
Filed: |
October 24, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10692707 |
Oct 24, 2003 |
|
|
|
09818380 |
Mar 27, 2001 |
|
|
|
60202259 |
May 5, 2000 |
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Current U.S.
Class: |
607/116 |
Current CPC
Class: |
A61N 1/05 20130101; Y10S
439/909 20130101 |
Class at
Publication: |
607/116 |
International
Class: |
A61N 001/05 |
Claims
What is claimed is:
1. A method of making a connector pin, comprising: providing a
pin-shaped mold; positioning a plurality of electrical contacts in
the pin-shaped mold; arranging the plurality of electrical contacts
in at least two rows; providing a plurality of conducting wires,
each having an end; electrically connecting the end of at least one
conducting wire to each of the electrical contacts; and introducing
insulating material into the mold to form a pin with electrical
contacts positioned in at least two rows along the pin.
2. The method of claim 1 further comprising providing a printed
circuit board for electrically connecting the end of at least one
conducting wire to each of the electrical contacts.
3. The method of claim 1 wherein electrically connecting the end of
at least one conducting wire to each of the electrical contacts
comprises providing a printed circuit board for electrically
connecting the end of at least one conducting wire to each of the
electrical contacts, and wherein positioning the plurality of
electrical contacts in the pin-shaped mold comprises positioning at
least a printed circuit board in a mold.
4. The method of claim 1 wherein the plurality of electrical
contacts are temporarily held together in an array with bridging
sections between the contacts, and the method further comprises
cutting the bridging sections.
5. The method of claim 1 wherein the contacts comprise stainless
steel, nickel-plated stainless steel, gold-plated beryllium copper,
titanium, tantalum, platinum, or platinum/iridium.
6. The method of claim 1 wherein the at least two rows are not
straight.
7. The method of claim 1 further comprising forming at least one
groove in the pin.
8. The method of claim 1 further comprising forming at least one
notch in the pin.
9. The method of claim 1 wherein the connector pin is configured to
provide electrical connection between any two selected from the
group consisting of an implantable pulse generator, a trial
stimulator, and external lead cable, a percutaneous lead extension,
an implantable lead extension, and a lead containing an electrode
array.
10. The method of claim 1 wherein the connector pin includes a
proximal portion and a distal portion and the method further
comprises forming at the proximal portion a means for securely
holding the pin.
11. The method of claim 1 wherein the connector pin includes a
proximal portion and a distal portion and the method further
comprises forming a strain relief at the proximal portion.
12. The method of claim 1 further comprising providing means for
maintaining alignment of the pin during use.
13. The method of claim 1 further comprising providing means for
assuring proper orientation of the pin during use.
14. The method of claim 1 further comprising providing means for
activating an electrical connection with the electrical contacts of
the pin.
Description
[0001] The present application is a Divisional of U.S. application
Ser. No. 09/818,380, filed Mar. 27, 2001, now allowed, which claims
the benefit of U.S. Provisional Application Ser. No. 60/202,259
filed May 05, 2000. These applications are incorporated herein by
reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a medical device
for stimulating tissue in a living body, and more particularly
relates to a multi-contact connector for use with such medical
devices.
BACKGROUND OF THE INVENTION
[0003] A variety of neurostimulation systems include an array of
electrodes, formed on a lead, that are electrically connected to an
implanted electronic package. Often, the electrical connection is
achieved in part via one or more lead extensions that connect to
the electronic package at a proximal end and connect to the lead
carrying the electrode array at a distal end (and together with the
lead carrying the electrode array, may be called a lead system).
For instance, for a typical neurostimulation system, the proximal
end of one or more lead extensions is connected to an implanted
pulse generator, while the distal end of the lead extension(s)
connects to one or more leads bearing electrode arrays, which
electrodes are positioned in the spinal column.
[0004] For many neurostimulation systems, it is common to perform a
"trial stimulation" wherein the electrodes are positioned at the
target location, while a pulse generator remains external to the
patient during the trial period. For a number of days, the
patient's response to a variety of stimulation parameters is
gauged, prior to performing the surgical procedure of implanting
the pulse generator in the patient's body. If the patient's
response to the trial stimulation is not acceptable, the pulse
generator is simply not implanted, and only the electrode
array/lead system needs to be removed.
[0005] For the trial stimulation period, a lead extension commonly
called a percutaneous lead extension connects, at its distal end,
to the proximal end of the electrode array lead. The percutaneous
lead extension lies in a tunnel through body tissues and extends
outside the body, where its proximal end is connected (possibly via
an additional external cable) to an external "trial
stimulator."
[0006] A typical surgical process for implanting a trial
stimulation system includes first using an electrode insertion
needle to implant the electrode array so that the electrodes are
positioned at the target stimulation site. The electrode insertion
needle is a hollow needle preferably carrying a removable
solid-core stylet. After the needle is situated, the stylet is
removed, leaving a hollow opening. To ensure the needle tip has
entered the epidural space, a loss of resistance procedure is
typically employed.
[0007] To prevent damage to the electrode array, a lead blank that
approximates the diameter of the electrode array lead may be
inserted into the needle to clear away any tissue obstructing the
path through the needle and into the epidural space. The lead blank
is then removed and the electrode array is passed through the
needle and cleared path into the epidural space.
[0008] When the series of electrodes are in the general vicinity of
the target, the physician fine-tunes placement by connecting the
electrode array to an external trial stimulator and soliciting
patient feedback of paresthesia for each electrode. After the
electrode array is properly positioned, the needle must be removed,
either by pulling it out over the end of the electrode array's
lead, or by disassembly if the connector at the proximal end of the
electrode array is larger than the needle. With the array
positioned at the target site, the surgeon secures the lead by
making an incision near the point where the lead enters the spine.
The lead is secured at that point via a lead anchor.
[0009] The physician then creates a tunnel between the anchored,
proximal end of the electrode array and the percutaneous exit site
(i.e., the location where the percutaneous lead extension exits the
body through the skin). At the incision where the lead is anchored,
the distal end of the percutaneous lead extension is connected to
the proximal end of the electrode array. A tunneling tool is used
to create the tunnel from the percutaneous exit site to this same
incision. The proximal end of the percutaneous lead extension is
attached to the tunneling tool, which pulls the proximal end of the
extension back through the tunnel as the tool is removed, and out
through the percutaneous exit site. The proximal end of the
percutaneous extension, now protruding through the skin, is
connected to the trial stimulator cable (possibly via an additional
external cable).
[0010] The percutaneous extension preferably has a small connector
at its proximal end to minimize the diameter of the tunnel through
which the extension is pulled. The larger the tunnel, the more
tissue trauma, post surgical pain, recovery time, and possibility
of infection.
[0011] In addition, for some patients, two electrode arrays are
used. With current designs, the surgeon typically creates a
separate subcutaneous tunnel for each percutaneous extension. It
would be a great advantage to need only one extension and one
subcutaneous tunnel.
[0012] Additionally, current connector designs typically have four
or eight contacts per connector pin. To increase the number of
contacts per connector, a connector with two (or more) pins is
typically used. This is often referred to as a dual connector.
[0013] A need exists for more compact electrical connections, both
inside and outside the body. In addition, a need exists for a
greater number of contacts per connector, without increasing the
size of the connector or space required for the connector
receptacle within an electronic package.
SUMMARY OF THE INVENTION
[0014] In view of the above, it would be preferable to have a
single percutaneous extension with a proximal connector having, for
example, 16 contacts on one small-diameter pin. The number of
subcutaneous tunnels would preferably be reduced to one, and the
size of the tunnel required to draw the connector through the
tunnel would also preferably be minimized.
[0015] The receptacle portion of the connection currently faces the
same limitation regarding number of contacts versus connector size.
For instance, available 16-contact connectors result in a
receptacle size that greatly impacts the overall size of an
electronic package. By creating a receptacle that accepts a
connector with a single small-diameter 16-contact pin, the
electronic device size is significantly reduced.
[0016] Other connection points within a trial stimulation setting
and within a "permanent" stimulation setting can benefit from a
design with the improvements described herein. For instance,
connections within the body, such as between the electrode array
lead or internal extension and the implanted pulse generator, are
generally quite bulky, especially for 16-contact (16-electrode)
configurations.
[0017] As such, the invention disclosed and claimed herein provides
a tool-less connector with multiple contacts and a compact design.
As a result, using this connector, e.g., within a trial stimulator
setting, a minimally invasive subcutaneous tunnel can be created
which should reduce tissue healing time, patient discomfort, and
infection risk. Advantageously, providing additional contacts
allows enhanced stimulation protocols and/or additional channels
for other purposes, such as for feedback. In some embodiments of
the invention, the mating receptacle of the connector allows for
multiple contacts while minimizing the space required for the
increased number of contacts.
[0018] One embodiment of the present invention provides a connector
pin containing multiple in-line contacts. Each "line" consists of a
row of independent contacts arranged in a linear array spaced along
the long axis of the pin. Each contact is connected to a conductor
that lies within the pin. Each conductor extends out through the
end of the pin and into a cable. This cable may be the body of a
percutaneous lead extension, an internal lead extension, or any of
a number of other components within a trial or "permanent"
stimulation setting.
[0019] In other embodiments of the present invention, a receptacle
is provided that has contacts arranged to align with the matching
contacts on the connector pin.
[0020] Additional embodiments of the invention provide contacts
that may be in the form of spring loaded pins or leaf-style
springs.
[0021] Yet other embodiments of the invention provide features that
prevent the contacts on the connector pin from touching the
contacts on the receptacle until all contacts are appropriately
aligned.
[0022] Thus, the present invention provides connector pins that
allow, inter alia, the diameter of a tunnel created for a
percutaneous lead extension to be minimized. By reducing the tunnel
diameter, recovery time, patient discomfort, and possibility of
infection are reduced. Using subject connectors/receptacles in
other system locations offers similar advantages due to the
decreased area affected by the surgery and the implanted
components.
[0023] Other advantages of the present invention include (but are
not limited to) decreased size of any electrical device that houses
a receptacle for a subject connector, access to a greater number of
simulation alternatives or other use of additional channels,
enhanced pin-to-receptacle contact schemes, and tool-less operation
of the connection. The connector pins of the present invention may
be used advantageously wherever an electrical connection is
required, such as between the percutaneous extension and any
external cable, between the percutaneous extension and the trial
stimulator, and/or between the fully implanted extension and the
implanted pulse generator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The above and other aspects, features, and advantages of the
present invention will be more apparent from the following more
particular description thereof, presented in conjunction with the
following drawings wherein:
[0025] FIG. 1A is a block diagram that illustrates an exemplary
system that can benefit from the present invention;
[0026] FIG. 1B illustrates examples of various types of electrode
arrays that may be used with the present invention;
[0027] FIG. 1C shows various components that interface with the
implantable electrode arrays of FIG. 1B or with other arrays;
[0028] FIG. 2 is an exploded trimetric view of a connector pin of
an exemplary embodiment of the present invention;
[0029] FIG. 3 is a trimetric view of the underside of the assembled
body of the pin of FIG. 2;
[0030] FIG. 4 is a side view of the body of the pin of FIG. 3;
[0031] FIG. 5A is an end view of a contact of the pin of FIGS.
2-4;
[0032] FIG. 5B is a section view through line 5B-5B shown in FIG.
4;
[0033] FIG. 5C is an end view of a contact of the pin of FIGS.
2-4;
[0034] FIG. 5D is a trimetric view of a contact of the pin of FIGS.
2-4;
[0035] FIG. 6A is an end view of the top section of the pin of
FIGS. 2-4;
[0036] FIG. 6B is a top view of the top section of the pin of FIGS.
2-4;
[0037] FIG. 6C is a side view of the top section of the pin of
FIGS. 2-4;
[0038] FIG. 7A is a trimetric view of a receptacle of an exemplary
embodiment of the present invention;
[0039] FIG. 7B is an end view of the receptacle of FIG. 7A;
[0040] FIG. 7C is a section view through line 7C-7C shown in FIG.
7B;
[0041] FIG. 8A is a trimetric view of a connector pin of an
exemplary embodiment of the present invention;
[0042] FIG. 8B is a trimetric view of the receptacle of FIGS. 7A-7C
and the connector pin of FIG. 8A;
[0043] FIG. 9A is a trimetric view of a receptacle of an exemplary
embodiment of the present invention;
[0044] FIG. 9B is an end view of the receptacle of FIG. 9A;
[0045] FIG. 9C is a side view of the receptacle of FIG. 9A;
[0046] FIG. 9D is a top view of the receptacle of FIG. 9A;
[0047] FIG. 10 is a trimetric view of the receptacle of FIGS. 9A-9D
and a connector pin of an exemplary embodiment of the present
invention;
[0048] FIG. 11A is a trimetric view of a connector pin of another
exemplary embodiment of the present invention;
[0049] FIG. 11B is a side view of the pin of FIG. 11A;
[0050] FIG. 11C is an exploded trimetric view of selected
components of the pin of FIG. 11A; and
[0051] FIG. 11D is a trimetric view of selected assembled
components of the pin of FIG. 11A.
[0052] Corresponding reference characters indicate corresponding
components throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0053] The following description is of the best mode presently
contemplated for carrying out the invention. This description is
not to be taken in a limiting sense, but is made merely for the
purpose of describing the general principles of the invention. The
scope of the invention should be determined with reference to the
claims.
[0054] For illustration purposes, the following description of the
present invention is shown in conjunction with a Spinal Cord
Stimulation (SCS) system. The SCS system depicted via a block
diagram in FIG. 1A illustrates an exemplary system that can benefit
from the present invention. As will be apparent to those of skill
in the art, the present invention may be applied to other systems,
whether or not the system components are intended to be implanted
into a living body. Any components intended to be used in a
surgical situation must be capable of sterilization for use within
an operating room (OR), and more preferably, may be sterilized with
ethylene oxide (ETO). In addition, non-biocompatible components
intended to be implanted are preferably hermetically sealed (e.g.,
processor chip(s) and related components of an implantable pulse
generator (IPG)), and any surfaces of components that will
interface with body tissues and/or fluids must be made of
biocompatible materials (e.g., the container for the components of
the IPG).
[0055] The components of the SCS system shown in FIG. 1A may be
subdivided into three broad categories: (1) implantable components
10, (2) external components 20, and (3) surgical components 30. As
seen in FIG. 1A, the implantable components 10 include an
implantable pulse generator (IPG) 100, an electrode array 110, and
(as needed) a lead extension 120. The stimulation is delivered via
electrode array 110. Extension 120 may be used to electrically
connect the electrode array 110 to IPG 100, if the lead containing
the electrodes (i.e., the electrode array 110) is not long enough
to reach the IPG implantation site.
[0056] In a preferred embodiment, IPG 100 comprises a rechargeable,
multichannel, 16-contact (or more), telemetry-controlled pulse
generator housed, for instance, in a rounded titanium enclosure.
The connector receptacle of the present invention preferably forms
an integral part of IPG 100, allowing electrode array 110 or
extension 120 to be detachably secured and electrically connected
to IPG 100. As will be understood by those of skill in the art, the
connectors/receptacles of the present invention, when implanted,
must be sealed (i.e., electrically isolated) to protect electrical
connections from shorting.
[0057] IPG 100 preferably contains stimulating electrical circuitry
("stimulating electronics"), a power source (e.g., a rechargeable
battery), and a telemetry system. Typically, IPG 100 is placed in a
surgically-made pocket either in the abdomen, or just at the top of
the buttocks. It may, of course, be implanted in other locations of
the patient's body. Once implanted, IPG 100 is connected to the
lead system, comprising one or more lead extensions 120, if needed,
and at least one electrode array 110. Lead extension 120, for
example, may be tunneled up to the spinal column. Once implanted,
electrode array(s) 110 and lead extension(s) 120 are intended to be
permanent. In contrast, IPG 100 may be replaced when its power
source fails or is no longer rechargeable, or as improved models
become available.
[0058] Advantageously, IPG 100 can provide electrical stimulation
through a multiplicity of electrodes (e.g., sixteen electrodes)
included within the electrode array(s) 110. Different types of
electrode arrays 110 that may be used with the invention are
depicted in FIG. 1B. A common type of electrode array 110 is the
"in-line" lead, as shown at (A), (B), and (C) in FIG. 1B. An
in-line lead includes individual electrodes 114 spread
longitudinally along a small diameter flexible cable or carrier
116. The flexible cable or carrier 116 carries small wires embedded
(or otherwise carried) therein from each electrode to a proximal
end of the lead (not shown), where such wires may be electrically
connected to IPG 100 (or to a lead extension 120, which in turn
connects to IPG 100).
[0059] An advantage of an in-line lead is its ease of implantation,
i.e., it can be inserted into the spinal canal through a small
locally-anesthetized incision while the patient is kept awake. When
the patient is awake, he or she can provide valuable feedback of
paresthesia for a given electrode or electrodes 114 for a given
positioning of the array 110. Note, as used herein, the term
"paresthesia" refers to that area or volume of the patient's tissue
that is affected by the electrical stimuli applied through the
electrode array. The patient may typically describe the paresthesia
as an area where a tingling sensation is felt.
[0060] To overcome migration problems often associated with in-line
electrodes, a different type of electrode array 110 may be used,
known as a paddle lead. Various types of paddle leads are
illustrated at (D), (E), (F) and (G) of FIG. 1B. In general, each
type of paddle lead is shaped with at least one wide platform 119
on which a variety of electrode configurations or arrays are
situated. For instance, lead (F) of FIG. 1B has two platforms 119a
and 119b, at the end of lead branches 117a and 117b, respectively.
Electrodes may be in a variety of shapes and configurations. For
example, leads (D) and (E) in FIG. 1B have two columns of
longitudinally staggered, rectangular-shaped electrodes 115. Arrays
of circular-shaped electrodes 115' are shown in (F) and (G) of FIG.
1B. As also seen in FIG. 1B, the electrodes may vary in number and
spacing, as well as shape and orientation.
[0061] Still other types of leads may be used with IPG 100 in
addition to the representative leads shown in FIG. 1B. For example,
the deployable electrode array disclosed in U.S. Pat. No. 6,205,361
represents a type of lead and electrode array that may be used with
the invention. The '361 patent is incorporated herein by reference
in its entirety.
[0062] Whichever type of lead and electrode array is used, an
important feature of the exemplary SCS system is the ability to
support one or more leads with two or more channels. Here, a
"channel" is defined as a specified electrode, or group of
electrodes, that receives a specified pattern or sequence of
stimulus pulses. Having multiple channels that may be connected to
multiple electrodes, positioned within one or more electrode arrays
so as to cover more tissue/nerve area, greatly facilitates
providing the type of stimulation pattern and stimulation
parameters needed to treat a particular patient.
[0063] As seen in FIGS. 1A and 1C, electrode array 110 and its
associated lead system typically, but not necessarily, interface
with the implantable pulse generator (IPG) 100 via a lead extension
120. As needed, e.g., for testing and/or fitting purposes,
electrode array 110 may also interface with an external trial
stimulator 140. Electrode array 110 may interface directly with
trial stimulator 140, or the connection may be made via one or more
percutaneous lead extensions 132 and/or through one or more
external cable leads 134. In this manner, the individual electrodes
included within electrode array 110 may receive an electrical
stimulus from either trial stimulator 140 or IPG 100.
[0064] Because of this percutaneous, or "through-the-skin"
connection, trial stimulator 140 is also referred to as a
"percutaneous stimulator" 140. The main purpose of stimulator 140
is to provide a stimulation trial (typically 2-7 days) with the
surgically placed electrode array 110 before implanting IPG
100.
[0065] Typically, during implant of the electrode array, when
stimulator 140 is under control of a surgeon, stimulator 140 is
connected to electrode array 110 through external cable(s) 134 and
possibly, but not necessarily, percutaneous extension 132. Then,
after implant, during a trial period when stimulator 140 is under
control of the patient, stimulator 140 is connected to electrode
array 110 directly through percutaneous extension 132. In other
words, once the patient leaves the operating room, there is
generally no need for external cable(s) 134.
[0066] Trial stimulator 140 preferably has circuitry that allows it
to perform the same stimulation functions as does IPG 100. Further,
the circuitry within trial stimulator 140 allows it to receive and
store programs that control its operation through a suitable
communication link 205 (FIG. 1A) with the clinician programmer 204.
Thus, with such link 205 established, the clinician programmer 204
may be used to program trial stimulator 140 in much the same way
that the clinician programmer is used to program IPG 100, once IPG
100 is implanted. Advantageously, link 205 is bi-directional,
thereby allowing programming data sent to the stimulator 140 from
clinician programmer 204 to be verified by sending the data, as
stored in the stimulator 140, back to programmer 204 from
stimulator 140. In one embodiment, link 205 comprises an infra-red
(IR) link; in another embodiment, link 205 comprises a cable
link.
[0067] As suggested in the block diagram of FIG. 1A, percutaneous
extension(s) 132 and lead extension(s) 120 are inserted through the
patient's tissue through the use of appropriate surgical components
30, and in particular through the use of tunneling tools 152, as
are known in the art, or as are especially developed for purposes
of spinal cord stimulation systems.
[0068] In a similar manner, electrode array 110 is implanted in a
desired position, e.g., adjacent the spinal column of the patient,
through the use of an insertion needle 154 and, if needed, a guide
wire 156. The insertion needle, for example, may be a 15-gauge
Touhy needle. Additionally, as required, a lead blank may be used
to aid in the insertion process. A lead blank is a somewhat
flexible wire that approximates the lead diameter. The lead blank
is used to clear the path through the insertion needle and into the
epidural space before inserting electrode array 110. Use of the
lead blank prevents damage to the electrode array when tissue is
obstructing the insertion path.
[0069] One manner of using surgical components 30 during an implant
operation is described in the above referenced deployable electrode
patent, U.S. Pat. No. 6,205,361.
[0070] Another exemplary manner of using surgical components 30
(FIG. 1A) during an implant operation of an in-line electrode array
may be summarized as follows: A fifteen gauge hollow needle 154 is
used to create an opening in the spinal canal to insert an in-line
array, e.g., an in-line array of the type shown in FIG. 1B (A),
(B), or (C). The hollow needle includes a removable stylet (solid
core) for use during the needle insertion. After the needle has
been situated, the stylet is removed to reveal the hollow opening
through needle 154. To ensure the needle tip has entered the
epidural space, a loss of resistance technique (commonly known to
those skilled in SCS procedures) would typically be employed.
[0071] As described above, a lead blank approximating the diameter
of the electrode array may then be inserted into needle 154 to
clear away any tissue obstructing the path through the needle and
into the epidural space. The electrode array 110 is then passed
through the needle into the epidural space.
[0072] Next, the surgeon will typically apply stimulation to
electrode array 110, soliciting patient feedback of paresthesia, to
confirm proper array placement. As stated previously, the electrode
array(s) 110 may interface directly with the trial stimulator 140,
or the connection may use one or more external cables 134.
[0073] After the electrode array 110 position is confirmed, the
electrode array needs to be secured. An incision is made adjacent
needle 154 so that the needle is visible via the wound. Needle 154
is then removed, preferably by pulling the needle over the proximal
end of the lead. Hence, if the connector at the proximal end of the
lead is larger than the fifteen gauge needle tube, a split needle,
or some other mechanism, must be used to allow removal of the
needle over the connector.
[0074] A section of the lead containing electrode array 110 is now
visible through the wound, where needle 154 was previously visible.
The section of the lead visible through the wound is carefully
pulled into the wound, followed by the entire proximal end of the
lead containing, at its distal end, electrode array 110. Since the
connector for electrode array 110 is pulled into the wound, it is
preferable that the diameter of the connector be minimized, and
most preferably be no larger that the diameter of the lead body.
Hence, the present invention may be used advantageously for this
connection. Once the lead is pulled through, the proximal end of
the electrode array no longer exits the body where needle 154 was
inserted, but exits instead through the wound. This is herein
called the spinal exit site.
[0075] Next, a lead anchor is placed around the electrode array's
lead and positioned at the spinal exit site. The anchor is secured
in place to prevent movement of the electrode array and its
lead.
[0076] If additional electrode arrays 110 are implanted, the above
procedure may be repeated for each array 110, or multiple needles
154 may be used at one time to implant multiple electrode arrays
110 at the same time.
[0077] If a trial stimulation period is to be used, a tunnel is
then created between a percutaneous exit site and the spinal exit
site. If the lead containing electrode array 110 is not long enough
to extend out the percutaneous exit site, one or more percutaneous
extension(s) 132 are used to connect electrode array 110 to
external trial stimulator 140. As described earlier and shown in
FIGS. 1A and 1C, electrode array 110 or percutaneous extension 132
may be connected to the trial stimulator 140 via one or more
external cable(s) 134.
[0078] The surgeon uses suitable tunneling tools 152 to create a
tunnel between a percutaneous exit site and the spinal exit site.
According to one alternative, the proximal end of either the
electrode array 110 or a percutaneous lead extension 132 is
attached to the distal end of the tunneling tool 152. As the
tunneling tool 152 is retracted, it pulls the proximal portion of
the lead back out through the tunnel as the tool is removed. In
another alternative, the tunneling tool 152 deposits a tube in the
tunnel created, through which the lead is threaded. The exiting end
of the lead may then be connected to either trial stimulator 140 or
external cable 134. Additional tunnels are typically created for
each electrode array 110.
[0079] Any connector that will be pulled or threaded through the
tunnel will preferably have a minimal diameter, and preferably a
diameter that is no larger than the diameter of the lead. As the
tunnel diameter increases, so does patient discomfort, recovery
time, and possibility of infection. As such, if the proximal end of
the lead containing the electrode array is to be pulled or threaded
through the tunnel, the connector at its proximal end will benefit
from the present invention. Likewise, if the connector at the
distal or proximal end of a percutaneous lead extension is to be
pulled or threaded through the tunnel, the present invention may be
used to minimize the connector diameter, and thus the tunnel
diameter.
[0080] Percutaneous extension 132 is typically at least 150 mm in
length, but may be as long as about 800 mm. The percutaneous
extension diameter is preferably minimized, e.g., no greater than 3
mm in diameter when it connects with a single 8 electrode array,
(e.g., an in-line electrode array having eight electrodes, or an
electrode of the type shown in FIG. 1B(G)), or preferably no
greater than 4 mm in diameter when it connects with a dual-8
electrode array, (e.g., an electrode array of the type shown in
FIG. 1B(E)).
[0081] If more than one electrode array 110 is implanted, and a
percutaneous lead extension 132 is used, it may be preferable to
use a connector at the distal end of extension 132 with more than
one receptacle, or more preferably, a receptacle that accepts two
or more pins. In this manner, the number of subcutaneous tunnels
may be reduced. The proximal connector of extension 132 would
preferably use the present invention to include contacts for all
electrodes in one connector. Thus, the teachings of the present
invention may be used in connections with multiple connector pins
and multiple receptacles.
[0082] Of course, connectors that are not tunneled or threaded
through body tissues can also incorporate the teachings of the
present invention. For instance, an external cable 134 preferably
has a connector based on the present invention, and the trial
stimulator 140 preferably has a receptacle based on the present
invention. In addition, when link 205 comprises a cable link, it
may advantageously use connections described herein for connecting
to trial stimulator 140 and clinician programmer 204.
[0083] The IPG and related components may similarly incorporate the
present invention. For instance, the connector pin(s) at the
proximal end of extension 120 are inserted into receptacle(s) in
the IPG 100. By using a connector and receptacle of the present
invention for this interface, the size of IPG 100 may be reduced,
so the surgical pocket for holding IPG 100 may be smaller. In
addition, the proposed design, materials, and construction methods
of the present invention may reduce the cost of connector
receptacles and/or connector pins. Connections that are implanted
need to be properly sealed to insulate electrical contacts from
shorting. Techniques for sealing connectors and insulating
electrical contacts are known to those of skill in the art.
[0084] Turning now to FIG. 2, an exploded view of connector pin 220
of the present invention is shown. Pin body 230 is preferably made
of a biocompatible material that is also an electrical insulator,
more preferably of polyurethane, silicone, or
polytetrafluorethylene (PTFE), and most preferable of epoxy,
styrene-butadiene, polysulfone, or the like. Body 230 preferably
comprises a tube with an outer diameter of about 3 mm to 4 mm, and
more preferably about 3.2 mm, and an inner diameter of about 1.5 mm
to 2 mm, and more preferably about 1.7 mm. Body 230 preferably has
a channel with an opening at the top along its length of about 1.5
mm to 2 mm wide, and more preferably about 1.7 mm wide.
[0085] The end of body 230 tapers to a blunt tip, to ease insertion
into a receptacle. Two or more rows of grooves 232 are formed along
body 230 where contacts 240 are positioned. For instance, as seen
in FIGS. 2 and 3, if two rows of eight contacts each are desired,
the end of body 230 preferably has eight grooves 232 along each
side. As best seen in FIGS. 4 and 5B, grooves 232 extend from the
top, open edge of the tube nearly to the bottom (contacts 240
should not touch at the bottom), then preferably extend into body
230. Therefore, in a preferred embodiment, each contact 240 (FIGS.
5A, 5B, and 5C) wraps around approximately one-third of body 230.
However, additional rows of contacts 240 are possible.
[0086] Contacts 240 are typically made of, for instance, stainless
steel, nickelplated stainless steel, gold-plated beryllium copper,
titanium, tantalum, or noble metal(s) such as platinum or
platinum/iridium. The contacts 240 are positioned in grooves 232
via any number of means known to one of skill in the art. For
instance, as shown in FIG. 2, each row of contacts may be formed in
one piece, as a contact array 242. Each individual contact 240 is
then removed from the array, via, e.g., cutting the bridging
sections 243 between contacts. Once separated from the array, each
contact 240 is pressed or snapped into a groove 232 in pin body
230. For example, in the alternative depicted in FIGS. 4 and 5A-5C,
a contact will slide from below into the section of groove 232
through pin body 230, then snap over the lip at the top of body
230.
[0087] Each contact 240 is connected to a suitable wire (not
shown), which extends out of connector pin 220 through a channel
248 in pin body 230 (FIG. 2). Each wire ultimately connects
(possibly through one or more extensions and additional connectors)
a contact 240 at a proximal end of the wire to an electrode
114/115/115' or other electrical component (e.g., a sensor) at the
distal end of the wire.
[0088] As seen in FIGS. 2 and 6A-6C, a pin top 250 completes
connector pin 220. Pin top 250 is preferably made of the same
material as pin body 230. Once contacts 240, with their wires, are
assembled along pin body 230, pin top 250 is set on top of body
230. Pin top 250 is preferably secured to body 230 via ultrasonic
welding, and more preferably with a medical-grade adhesive. As best
seen in FIGS. 6A-6C, top 250 is shaped so that part of the top
extends into body 230, which helps hold the wires in place and also
forms a better connection and seal.
[0089] More preferably, individual contacts 240 and their
associated wires are placed into a mold as mold inserts, and the
insulating material for pin 220 is then used to fill the mold,
which securely affixes contacts 240 to the outside of pin 220. In
this case, the wires would be encased in pin 220, which is
preferably solid, without a separate pin body 230 and pin top 250.
Alternatively, as indicated earlier, each row of contacts may be
formed as a contact array 242 (FIG. 2). After molding, bridging
sections 243 between contacts 240 are preferably protruding from
pin 220, so the contacts are readily separated by removing the
bridging sections, via, e.g., cutting. Other alternatives for
forming and joining pin 220 and contacts 240 will be apparent to
those skilled in the art.
[0090] Referring next to FIGS. 7A-7C, contacts 240 along the length
of connector pin 220 make electrical contact with receptacle
contacts 270 along the inside of a receptacle 260 when connector
pin 220 is inserted into receptacle 260. Receptacle contacts 270
are, in turn, electrically connected to wires leading either to
another lead/cable, such as lead extension 120, percutaneous
extension 132, or external cable 134, or to an electrical device,
such as IPG 100 or trial stimulator 140. Receptacle contacts are
typically made of, for instance, stainless steel, nickel-plated
stainless steel, gold-plated beryllium copper, titanium, tantalum,
or noble metal(s) such as platinum or platinum/iridium.
[0091] In the embodiment depicted in FIGS. 7A-7C, receptacle
contacts 270 comprise spring-loaded pins, also known as spring
plungers. These spring-loaded pins typically comprises a helical
compression spring biased into a position that causes the distal
tip of spring-loaded pin to protrude into receptacle 260. During
insertion into receptacle 260, connector pin 220 pushes the distal
tip of the each spring-loaded pin in a proximal direction, which in
turn compresses the spring within each spring-loaded pin. Once
connector pin 220 is fully inserted, the distal tip of each
spring-loaded pin is pushed distally by its spring into contacts
240 in the side of connector pin 220. Suitable spring-loaded pins
are commercially available from Interconnect Devices, Inc. of
Kansas City, Kans.
[0092] As is readily apparent from FIGS. 7A and 7C, in some
preferred embodiments, eighteen receptacle contacts 270 are
provided, which would electrically connect to eighteen pin contacts
240. As mentioned earlier, providing additional contacts allows
enhanced stimulation protocols and/or additional channels for other
purposes, such as for feedback.
[0093] A preferred connector pin 220 for use with the receptacles
depicted in FIGS. 7A-7C is shown in FIGS. 8A and 8B. Between two
rows of contacts 240 is a hooked groove 280. On the side of
connector pin 220 opposite hooked groove 280 is another groove (not
shown), which may or may not be hooked. As shown in FIG. 8B, when
connector pin 220 is inserted, it should be rotated so that grooves
280 align with the distal ends of receptacle contacts 270. This
will also allow groove 280 to slide over locking pin 272 (FIGS. 7B
and 7C).
[0094] Locking pin 272 guides connector pin 220 during insertion
into receptacle 260. As locking pin 272 reaches hook 282 of groove
280, connector pin 220 is turned as locking pin 272 slides along
hook 282. As the locking pin reaches the end of groove 280, at the
tip of hook 282, all contacts 240 become properly connected to
their respective receptacle contacts 270. Therefore, if the
connector pin 220 is intended to be inserted in only one
orientation, it is preferable that only one groove 280 include a
hook 282. In this preferred embodiment, therefore, contacts 240 are
advantageously prevented from touching receptacle contacts 270
until all contacts are appropriately aligned.
[0095] In another alternative, the receptacle 260 shown in FIGS.
9A-9D is used. Receptacle contacts 270 are comprised of
leaf-springs secured to the receptacle. These leaf-springs are
preferably thin pieces of metal formed into a shape that allows the
springs to return to their original position after moderate
displacement. Thus, receptacle contacts 270 of FIGS. 9A-9D are
biased to make reliable electrical connections with contacts 240
when connector 220 (FIG. 10) is fully inserted, yet the
leaf-springs may be displaced slightly to allow easy insertion of
the connector.
[0096] Furthermore, the configuration of leaf-spring receptacle
contacts 270 aids in holding connector pin 220 in place after
insertion. (As expected, connector pin 220 of FIG. 10 comprises two
rows of contacts 240, with the second row positioned on the side
opposite the contacts 240 visible in FIG. 10.)
[0097] As best seen in FIG. 9D and FIG. 10, receptacle 260 and
connector pin 220 are keyed to allow insertion of the connector pin
in only one orientation. A channel 286 is provided in receptacle
260 that accepts the section of connector pin 220 with a notch 276.
Since connector pin 220 will not fit into receptacle 260 in any
other orientation, contacts 240 are advantageously prevented from
touching the leafspring receptacle contacts 270 until all contacts
are properly aligned.
[0098] In yet another alternative, the connector pin 220 shown in
FIGS. 11A and 11B is used. Once again, connector pin 220 comprises
two rows of contacts 240, with the second row positioned on the
side opposite the contacts 240 visible in FIGS. 11A and 11B.
Connector pin 220 of FIGS. 11A and 11B is comprised of an outer
portion 290, which is preferably but not necessarily molded of a
thermoplastic polymer material, such as Lexan.RTM. PC polycarbonate
resin, Ultem.RTM. polyetherimide (PEI), or the like. Outer portion
290 may alternatively be cast, in which case, outer portion 290 may
be made of an epoxy resin material, such as Hysol.RTM. resin, or
the like.
[0099] Outer portion 290 preferably has a grooved portion 292,
which advantageously provides for a secure hold to the lead cable
or carrier 116 (not shown) and a strain relief portion (not shown)
that is preferably overmolded to the grooved portion and lead
cable. Additional grooves, or alternative configurations, such as
dimples, spirals, etc., may be used.
[0100] Contact portion 294 and end portion 296 are configured to be
inserted into a receptacle. End portion 296, when used, preferably
provides a means for activating the electrical connections between
the contacts 240 in connector pin 220 and the receptacle contacts
270 with, e.g., an electrically or mechanically activated switch
298 or other means known in the art. Alternatively, connector pin
220 may incorporate a grooved hook or the like, as described above,
to prevent electrical contact until the pin and receptacle contacts
are properly aligned. In addition, contact portion 294 is
preferably keyed, such as with a flat top and rounded bottom as
shown, to allow insertion of the connector pin in only one
orientation.
[0101] Internal to connector pin 220 is preferably a printed
circuit board (PCB) 300 (FIGS. 11C and 11D), made using techniques
known in the art of PCB manufacturing. For instance, PCB 300 may be
made of multiple layers, each containing a number of the traces
(e.g., gold plated copper traces) on its top and bottom which carry
electrical current from conductor pads 302, where the lead
conductors are soldered, to contact pads 304, where the contacts
240 are soldered. To do this, conductor pads 302 and contact pads
304 preferably include plated-through holes 306, made via
traditional means known in the PCB art, e.g., by ionic deposition,
electroplating, or the like. Conductor pads 302, contact pads 304,
and the material deposited in the plated-through holes 306 is
preferably gold or other conductive metal.
[0102] Contacts 240 are preferably manufactured by stamping the
desired contact shape out of a sheet 308 of material, such as
stainless steel, nickel-plated stainless steel, gold-plated
beryllium copper, titanium, tantalum, or noble metal(s) such as
platinum or platinum/iridium. Contacts 240 are soldered to contact
pads 304, then removed from sheet 308 via bending, breaking,
trimming, or the like. Alternatively, contacts 240 may be removed
from sheet 308 prior to soldering the contacts to contact pads
304.
[0103] Alternatively, contacts 240 could be made by depositing gold
or other conductive metal at PCB edges 310, similar to depositing
in the plated-through holes 306 extending through the PCB. This
would make sheet 308 unnecessary, and contacts would not need to be
soldered to the contact pads or removed from the sheet. When this
method is used, edges 310 are preferably, but not necessarily,
rounded from top to bottom, to better conform with the shape of
outer portion 290.
[0104] Switch 298 may be a ring or similar structure that fits at
the end of PCB 300. If switch 298 is intended to be an electrical
switch, it is preferably plated with, e.g., gold, and soldered,
molded into, or similarly attached to PCB 300. In one alternative,
a trace on one of the layers of PCB 300 electrically connects a
conductor pad 302 to switch 298. In another alternative, receptacle
260 has one or more receptacle contacts 270 that are electrically
activated by switch 298. For instance, two specialized contacts
within the connector receptacle may contact switch 298, thereby
completing a circuit that activates all electrical connections
between pin contacts 240 and receptacle contacts 270. In these
cases, switch 298 is preferably smaller in diameter than pin
contacts 240 to prevent unintended contact between switch 298 and
receptacle contacts 270. Other alternatives are possible, such as a
mechanical switch mentioned earlier. It is preferable that switch
298 is activated (by closing a circuit or other method), thus
electrically activating the device, only after all pin contacts and
receptacle contacts are aligned.
[0105] As mentioned earlier, outer portion 290 is preferably
provided by placing the finished subassembly of PCB 300, contacts
240, switch 298, conductor pads 302 with wires attached, etc. into
a mold and molding, via insert molding or other molding method
known in the art, outer portion 290. Connector pin 220 of FIGS. 11A
and 11B may advantageously be used with the receptacles 260
previously described, with slight modifications made to
accommodate, e.g., end portion 296, switch 298, and/or the flat top
of contact portion 294. Upon reading the information herein, those
of skill in the art will be capable such modifications.
[0106] An additional advantage of the connector pin 220 and
receptacle 260 combinations disclosed herein are their tool-less
operation. Although not a required feature, tool-less electrical
connections between connector pin 220 and receptacle 260 will
result in less surgical time, and less opportunity for error. The
present invention provides small connector pins 220, that are
preferably configured to provide tool-less connections to
receptacles 260 and are preferably keyed to allow only one
connection orientation.
[0107] While the invention herein disclosed has been described by
means of specific embodiments and applications thereof, numerous
modifications and variations could be made thereto by those skilled
in the art without departing from the scope of the invention set
forth in the claims. For instance, more than two rows of contacts
240 on connector pin 220 may make electrical connection with more
than two rows of receptacle contacts 270 in receptacle 260. This
allows for additional electrical components, such as electrodes
114, 115, and/or 115' positioned at the distal end of cable 116, or
allows for additional electrode arrays 110 to connect to one
device, such as IPG 100 or trial stimulator 140. In another
variation, the rows of contacts may not be straight. For instance,
the contacts may be in staggered positions around the pin, or may
be arranged helically, with the contacts in the receptacle
preferably arranged to coincide with the contacts along the
connector pin.
* * * * *