Vacuum-assisted wound healing around a pin-site

Information

  • Patent Application
  • 20080051828
  • Publication Number
    20080051828
  • Date Filed
    August 02, 2006
    17 years ago
  • Date Published
    February 28, 2008
    16 years ago
Abstract
A vacuum-assisted wound healing device is provided comprising an airtight hollow conical member surrounding a skin-breaching bone stabilization device, and a port for attaching a suction tube. The conical member has an opening at one end conforming to the circumference of the shaft of a bone stabilization device, and a opening at the other end to enclose a wound in a patient's skin surrounding the bone stabilization device. The device may be used to provide controlled reduced pressure to the wound site, reducing healing time and risk of infection.
Description

BRIEF DESCRIPTION OF THE FIGURES


FIG. 1 shows a perspective view of a wound treatment device for applying therapeutic vacuum to a wound surrounding the shaft of a bone stabilization device that extends through a patient's skin.



FIG. 2 shows a perspective view of an alternative embodiment of a wound treatment device for applying therapeutic vacuum to a wound surrounding the shaft of a bone stabilization device that extends through a patient's skin.



FIGS. 3A-3C show an enlarged perspective view of an alternate port design in three stages of operation—before insertion of the tube, with the tube inserted and withdrawing air, and after sealing.



FIG. 4 shows a perspective view of a further alternative embodiment of a wound treatment device for applying therapeutic vacuum to a wound surrounding the shaft of a bone stabilization device that extends through a patient's skin.





Although these Figures depict an embodiment of the contemplated invention, they should not be construed as foreclosing alternative or equivalent embodiments readily apparent to those of ordinary skill in the subject art.


DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG. 1, a wound treatment device 10 is provided for applying a therapeutic vacuum for treating a wound 15 caused by a bone stabilization device 11 that protrudes through a patient's skin 13. In the embodiment shown in FIG. 1, the device 10 includes a hollow, preferably generally conical member 12. At one end, the conical member 12 has a small opening conforming to the shaft of the bone stabilization device 11. At the other and opposite end, the conical structure 12 has a larger opening that is dimensioned to enclose the wound 15 surrounding the bone stabilization device 11. While the openings in the generally conical member 12 will typically be circular, it is noted that other shape openings are possible. For example, the body of the conical member may be oval in cross-section, and the opening contacting the skin will be oval. Likewise, the shape of the opening for engaging the shaft of the bone stabilization device is advantageously selected to conform to the cross-sectional shape of the shaft, if other than circular.


It is also contemplated that the openings may not be predetermined, instead being defined by the attachment of the member 12 to the bone stabilization device 11. Thus, in the event that the stabilization device is rectangular, the upper opening would conform to the shape of the device upon application of negative pressure, as will become more apparent below.


Preferably, the conical member is comprised of a flexible, semi-rigid, airtight material so that when reduced pressure is applied, the walls of the conical member are drawn inwards toward the skin and stabilization device. In a preferred embodiment, the conical member is comprised of a flexible, semi-rigid polymer such as silicone or low linear density polyethylene. Ideally, the cone geometry is such that while the ends of the cone conform to the stabilization device and the skin respectively, the middle section of the cone is drawn inwards under the applied negative pressure. Use of a flexible but semi-rigid polymer in the conical member allows the structure to conform roughly to the surfaces of the stabilization device shaft and the patient's skin while also retaining its shape when the vacuum is applied. Whatever material is used, the conical member preferably has sufficient flexibility at the end having the smaller opening to contract against the stabilization device and form an air tight seal, but preferably has sufficient rigidity to generally maintain its conical shape and prevent the structure from collapsing onto the wound, as well as the ability to securely support the vacuum port and tube. The conical member should also have sufficient flexibility at the opposite end to form an airtight seal with the skin. The conical member 12 can be optionally secured to the stabilization device 11 and to the skin 13 by adhesive 14. Any suitable adhesive which can adhere to the skin can be used.


As shown in FIG. 1, the wound 15 is completely enclosed within the conical member 12. Negative pressure is supplied to the interior of the enclosure formed by the member through a tube 16. The tube 16 connects to the conical member 12 through a port 18 formed in the conical member 12, preferably at a location that is between the ends of the conical member. Tube 16 connects the port 18 to a vacuum source (not shown) which supplies a negative pressure (vacuum) to the space inside the conical member 12. The tube 16 may be either integrally connected to port 18, or it may be capable of attachment by any commonly understood or suitable means. In a preferred embodiment, the tube measures ¼ inch in diameter and is comprised of a flexible polymer such as polycarbonate, e.g. LEXAN® brand polycarbonate.


While the port 18 and tube 16 are both shown as cylindrical in shape, it is also contemplated that either or both can be formed in a variety of shapes. For example, referring to FIGS. 3A-3C, the port 18 can be formed from two flaps of material that extend from the member 12 and which flaps are attached at their upper and lower ends, thereby defining a narrow slit. The tube 18 can be easily inserted into the slit when a vacuum is needed. After sufficient negative pressure is applied to the enclosure, the flaps can then be closed, such as by clipping or taping, and the tube 18 removed.


The level and duration vacuum pressure necessary to achieve a suitable antiseptic effect is well understood in the art. In a preferred embodiment, the vacuum pressure applied is 5 in Hg below atmospheric pressure until the bacterial count is reduced to a desired level. Although not shown, a sensing device can be located along the tube for monitoring bacterial count. Alternately, when substantially all the air is withdrawn from the enclosure, the enclosure could be sealed.


As shown in FIG. 2, an alternative form of the device of the invention includes a slit 20 in the member which extends from one end to the other. This allows the device to be opened to fit around the shaft of a bone stabilization device which has already been inserted into the body of the patient, where access to the end of the stabilization device is blocked, for example, by a bar, rack, brace or frame or other structure, as shown in FIG. 2. The slit is then sealed, preferably by means of flexible adhesive material, such as adhesive tape or glue 14. This method of attachment enables the device to be used when the stabilization device is itself attached to a larger apparatus, such as in the case of a badly shattered bone where a series of pins or screws may be attached to a rack or brace 21. It should be readily apparent that the shape of the member 12 in this embodiment need not be conical before application of pressure. Instead, the member 12 may be formed from flexible material that has a flat sheet with a square, trapezoidal, or other shape. The sheet is wrapped around the pin and sealed to the pin and the skin, thus defining the conical shape.


The embodiment of the device of the invention shown in FIG. 1 may be fitted to the patient by passing the bone stabilization device shaft axially through the openings in the conical member until the larger opening contacts the patient's skin. Where the protruding end of the bone stabilization device is connected to a rack or frame, the alternative embodiment of the device of the invention, as shown in FIG. 2, is preferably employed. The stabilization device shaft passes through the slit in the conical member until the shaft extends through each opening in the conical member. The vacuum pressure is applied at either a constant or cyclical rate and for a time period sufficient to achieve the desired antiseptic effect as understood by those of ordinary skill in the art.


As shown in FIG. 4, an alternative form of the device of the invention includes a conical member 12 that is sufficiently flexible to collapse under the pressure difference between external ambient pressure and the negative pressure inside the conical member. To protect the wound 15, a soft element 22, which may be a sponge, is placed between the conical member 12 and the wound. The soft element 22 may be treated with an antimicrobial substance. The antimicrobial sponge may be supplied in a package with the conical member 12 when the wound treatment device is supplied, or may be provided separately and combined with the conical member only when the wound treatment device 10 is applied to a patient. In some circumstances, the mechanical contact between the soft element 22 and the wound 15, where gentle mechanical forces are transmitted to the wound from the conical member 12 through the soft element 22, may mechanically stimulate the wound in such a manner as to promote healing. The use of the flexible conical member 12 without the soft element 22 is possible but in most circumstances less preferred.


All references cited herein are incorporated by reference. The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof.


For example, although distinct embodiments have been described and shown in the several drawings, features from the different embodiments may be combined in a single embodiment. For example, the treatment device 10 shown in FIG. 4 may have either the connector 18 shown in FIG. 1 or the connector shown in FIGS. 3A to 3C. For example, the treatment device 10 shown in FIG. 4 may have a conical shape similar to that shown in FIG. 1 or may have the slit 20 shown in FIG. 2.


Accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indication the scope of the invention.

Claims
  • 1. A device for applying therapeutic vacuum to a wound surrounding the shaft of a bone stabilization device that extends through the skin of a patient, comprising: a hollow generally conical member having at a first end a first opening adapted to conform to the bone stabilization device shaft, and having at a second opposite end a second opening adapted to enclose a wound surrounding the bone stabilization device shaft;the conical member having, at a point between the ends thereof, a port for connecting a suction tube to the conical member to communicate a negative pressure from a vacuum source to a space defined by the conical member;the conical member having sufficient flexibility at the first end to form an airtight seal around the stabilization device shaft.
  • 2. A device according to claim 1, wherein the conical member has sufficient rigidity to resist collapsing onto the wound during use.
  • 3. A device according to claim 1, wherein the conical member has sufficient flexibility to collapse onto the wound during use, further comprising a soft element dimensioned to be placed between the conical member and the wound, and to separate the collapsed conical member from the wound.
  • 4. A device according to claim 1, further comprising a sealable slit in the conical member extending from said first opening to said second opening.
  • 5. A device according to claim 1, wherein the first opening is generally circular.
  • 6. A device according to claim 1, wherein the second opening is generally circular.
  • 7. A method of treating a wound surrounding the shaft of a bone stabilization device that protrudes through the skin of a patient comprising: placing the device of claim 1 over a wound and protruding bone stabilization device shaft such that the shaft passes through both openings in the conical member and the device encloses the wound;connecting the vacuum tube to a source of vacuum; andapplying vacuum pressure to the device.
  • 8. The method of claim 7, wherein the applied vacuum pressure is constant.
  • 9. The method of claim 7, wherein the applied vacuum pressure is cyclical.
  • 10. The method of claim 7, wherein the edge of the second opening in the conical member is adhered to the skin of the patient with an adhesive.
  • 11. The method of claim 7, wherein the edge of the first opening in the conical member is adhered to the shaft of the bone stabilization device with an adhesive.
  • 12. A device for applying therapeutic vacuum to a wound surrounding the shaft of a bone stabilization device that extends through the skin of a patient, comprising: a hollow member formed from a sheet of material impervious to air, the hollow member having a first opening located at a first end, the first opening adapted to conform to the bone stabilization device shaft, and having a second opening at a second end of the hollow member, the second end being spaced axially apart from the first end, the second opening being larger than the first opening and adapted to enclose a wound surrounding the bone stabilization device shaft;the hollow member having a port located at a point between the first and second ends, the port permitting air passage between the inside of the hollow member and the outside of the hollow member, the port adapted to connect with a suction tube for communicating a negative pressure from a vacuum source to a space inside the hollow member;the hollow member having sufficient flexibility at the first end to form an airtight seal around the stabilization device shaft.
  • 13. A device according to claim 12, wherein the hollow member has a shape that resists collapsing of the hollow member onto the wound during use.
  • 14. A device according to claim 12 wherein the port is formed integral with the member.
  • 15. A device according to claim 12 wherein the member has flaps which extend out from the sheet, the flaps defining the port.