Antimicrobial Wound Dressing and Skin Fixator for Orthopedic Pins

The present invention is directed to a device which serves as an antimicrobial wound dressing, skin fixator and anchoring device for orthopedic pins.

Orthopedic pins, which are normally used in medical practice to temporarily immobilize and/or suture fractured bones, cause a breach in the skin. This wound provides a path for normal skin microorganisms to invade along the pin wound tract into deeper tissues, thus threatening the therapy being utilized and the health of the patient. Moreover, the potential for antimicrobial infection along the pin tract is increased by the relative motion of the pin into and out of the wound, and by bacterial proliferation at the wound site. Moreover, tissues contacting the pin are in a state of chronic inflammation, thus impairing the normal defense mechanisms against the progressive bacterial infection.

Thus it is an object of the present invention to stabilize an orthopedic pin at the wound site.

It is a further object of the present invention to provide an antimicrobial wound dressing at the pin site which can protect the wound site from the environment.

It is a further object of the present invention to provide a device which can be used both to anchor a pin with respect to the wound site and serve as a wound dressing, but which is disposable and readily replaced as needed without removing the pin or without undo disruption at the wound site.

These and other objects will be apparent from the following description and from the practice of the invention.

The present invention is directed to an antimicrobial orthopedic pin percutaneous protection kit. The kit comprises a shield comprising a central elastomeric collar having a longitudinal orifice and having one end of the collar substantially orthogonally disposed to an elastomeric, porous, peripheral flange, the flange extending around the end of the collar, with a radial slit extending through the collar and flange from the longitudinal orifice of the collar to the outer edge of the flange to provide a lateral insertion route for an orthopedic pin into the collar. The shield is adapted with means for securing the collar around an orthopedic pin to prevent longitudinal motion of the pin through the collar. The kit also comprises an absorbent patch containing an antimicrobial agent, centrally attached to a porous pad, the pad and patch having a pressure-sensitive adhesive coating on the exposed surface of the patch and the surrounding surface of the pad. The maximum dimensions of the pad are such that when the pad is placed upon the skin of a patient the superimposition of the shield upon the pad prevents contact of the flange of the shield upon the skin of patient. The patch and pad have a radial slit extending from a central point of the pad and patch to the outer edges of the pad and patch to provide a lateral insertion route of an orthopedic pin and to the pad and patch.

FIG. 1 is an exploded perspective view of one embodiment of the present invention showing a shield and pad/patch combination;

FIG. 2 is a partial cross-sectional of the pad and patch shown in FIG. 1.

Referring to FIG. 1, an orthopedic pin shield 10 formed of an elastomeric material such as polyurethane, formed for example by conventional vacuum formation, injection molding or other means, is sterilizable and compatible with medication and body tissues. The shield 10 comprises a porous elastomeric peripheral flange 11 which is made porous by ventilation holes 12 and/or micropores (not shown) of sufficient size to allow the passage of moisture therethrough. Flange 11 may be flat, or have a slight curvature, as shown, to conform to skin surfaces. Co-formed or separately made and later attached, with the flange 11 is a central collar 13 orthogonally projecting above the plane of the flange 11. A radial slit 14 communicating the interior of collar 13 with the outer edge of flange 11 allows the insertion of an orthopedic pin into the collar 13 from a lateral direction. Eyelet 15 is co-formed or separately formed and later attached to, the exterior surface of the collar 13. Additional eyelets 16 are located on the flange 11 on either side of the radial slit 14.

The other component of the kit according to the present invention is an absorbent patch 18 centrally attached to a pad 17. The exposed surface of the pad 17 contains a pressure-sensitive adhesive for the attachment of the pad 17 to the skin of a patient, which serves in part to hold the patch 18 in close contact with the wound site formed by the orthopedic pin (not shown). A radial slit 19 communicates an interior orifice 20 of the pad 17 and a central point of patch 18, respectively, with the outer edges to allow the insertion of the pin into the orifice 20 and patch 18 from a lateral direction. It will be appreciated that orifice 20 may be of any desired dimension to accommodate different sized pins.

Referring to FIG. 2 there is shown a partial cross-section of the pad and patch shown in FIG. 1. The cross-sectional view shows the additional feature of the removable tab 21 (shown in section) which covers the lower adhesive surface of the pad 17 (shown in section) for storage prior to use. The tab 21 may be made of any convenient material, such as paper or plastic. The tab (or tabs) is removed prior to the use of the pad 17 and patch 18.

During use, the tab 21 is removed from the pad 17 and patch 18 and the adhesive surface is placed onto the skin of a patient with the orthopedic pin extending through the orifice 20 and patch 18. Both the pad 17 and patch 18 are sufficiently porous to allow the passage of moisture therethrough. For use the shield 10 is placed over the pad 17 with the orthopedic pin (not shown) being inserted into the collar 13. The shield 10 is aligned with the pad 17 for the purpose, in part, of avoiding any abrasive effect of the flange 11 on the skin of the patient. The collar 13 is then tightened around the orthopedic pin (not shown) by inserting a suture or other suitable tying means (not shown) through the eyelets 15 and 16. The eyelets 16 are secured together by tying a knot to maintain closure of the radial slit 14, and the collar 13 is secured tightly around the orthopedic pin by tying a knot through eyelet 15 around the circumferential diameter of the collar 13.

The antimicrobial material contained in patch 18 may be any available antimicrobial agent such as chlorhexidene or an antimicrobial silver salt. In one particularly preferred embodiment the patch 18 is made of collagen and antimicrobial agent will be absorbed therein. The collagen will serve as an antimicrobial drug reservoir whereby the antimicrobial drug will be released gradually, thus providing a long-acting antimicrobial surface at the wound site.

In one modification the pad 17, flange 11 and/or interior of collar 13 may be impregnated with an antimicrobial agent to further reduce the risks of infection at the wound site. This is advantageous because incidental axial movement of the orthopedic pin through the collar 13 would result in a squeegee effect whereby bacteria are wiped off the orthopedic pin surface as it passes through the collar and into the tissues, and the antimicrobial agent is wiped over the orthopedic pin to further deter infection.

In a particularly preferred embodiment, the pad 17 and patch 18 may be used alone, without shield 10, in instances where pressure upon the skin and wound site caused by the immobilized shield 10 upon the orthopedic pin needs to be avoided. By using the patch 17 and pad 18 alone, minimal pressure is exerted upon the wound site and the orifice 20 serves to provide a squeegee effect whereby bacteria are wiped off the orthopedic pin surface as it passes through the orifice and into the tissues and antimicrobial agent is wiped over the orthopedic pin to further deter infection. If it is to be used without the shield 10, the patch 17 may be fabricated with an integral collar (not shown) centrally disposed thereon, and an eyelet similar to collar 13 and eyelet 15. In such a configuration the collar may also be impregnated with an antimicrobial agent.

The orthopedic pin kit according to the present invention may be used with any type of percutaneous device, particularly with bone fixation pins.

Having described the preferred embodiments of the present invention, it will be apparent to those skilled in the art that various modifications and variations may be made within the spirit and scope of the invention. The present invention is not to be limited except by the scope of the following claims.