Patent Abstract:
A portable therapeutic device and method of use generate longitudinally propagating ultrasound and shear waves generated by such longitudinally propagating ultrasound to provide effective healing of wounds. A transducer having an operative surface is disposed substantially adjacent to the wound to emit ultrasound to propagate in the direction of the wound to promote healing. Reflections of the ultrasound by bone tissue, by skin layers, or by internally disposed reflective media propagate toward the wound as longitudinal waves, with shear waves generated by the longitudinal waves for the healing of the wound. A focusing element is used for focusing the propagation of the ultrasound at a predetermined angle toward the wound. The operative surface of the transducer may be annularly shaped to encircle the wound to convey the ultrasound and/or reflected ultrasound thereto. A housing may be provided for positioning the transducer near a portion of the skin near the wound, and for indenting the skin to form a cavity, with the transducer disposed in the cavity to emit the ultrasound toward an internal surface of the wound. Fixture structures, such as adjustable straps, may extend about a portion of the body to position the transducer near the wound.

Full Description:
PRIORITY 
     The present application is a divisional application of U.S. patent application Ser. No. 08/886,217 filed on Jul. 1, 1997, now U.S. Pat. No. 5,904,659 issued on May 18, 1999, which is a continuation application of U.S. patent application Ser. No. 08/799,240 filed on Feb. 14, 1997 now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This disclosure relates to the non-invasive application of ultrasonic energy to enhance and/or accelerate the process of wound healing, and more particular, to the healing of wounds including ulcers, such as venous ulcers. 
     2. Description of the Related Art 
     Venous ulcers on human legs have proven difficult to treat, for example, because of the lack of vascularization in and around the wound. 
     The term “wound” for the purposes of “wound healing”, as used throughout the present disclosure, includes ulcers such as venous ulcers as well as burns, ulcerated wounds due to, for example, diabetes, surgical incisions or other surgical cuttings including stitched surgical cuttings, skin grafts, hair transplants, re-vascularization, bed sores, tissue dehiscence, and ligament and tendon repair and reconstruction. In general, as used throughout the present disclosure, the term “wound healing” encompasses addressing damage to, repair of, or restoration of soft tissue. 
     U.S. Pat. No. 4,530,360 to Duarte (hereafter “Duarte”), describes a basic therapeutic technique and apparatus for applying ultrasonic pulses from an ultrasonic applicator placed on the skin at a location adjacent a bone injury. Duarte gives a range of radio frequency (RF) signals for creating the ultrasound, ultrasonic power density levels, a range of duration of each ultrasonic pulse, and a range of ultrasonic pulse frequencies. The length of daily treatment is also described in Dart. The Dart patent is incorporated herein by reference. 
     U.S. Pat. Nos. 5,003,965 and 5,186,162, both to Tallish and Lifshey (hereafter “Tallish &#39;965” and “Tallish &#39;162”, respectively) describe an ultrasonic delivery system in which the RF generator and transducer are both part of a modular applicator unit which is placed at the skin location. The signals controlling the duration of ultrasonic pulses and the pulse repetition frequency are generated apart from the applicator unit. Tallish &#39;965 and Tallish &#39;162 also describe fixture apparatus for attaching the applicator unit so that the operative surface is adjacent to the skin location. In one application described in Tallish &#39;965 and Tallish &#39;162, the skin is surrounded by a cast. 
     U.S. Pat. No. 5,211,160 to Tallish and Lifshey (hereafter “Tallish &#39;160”) also describes a fixture apparatus which is mounted on uncovered body parts; i.e. without a cast or other medical wrapping. Tallish &#39;160 also describes various improvements to the applicator unit. Each of Tallish &#39;965, Tallish &#39;162, and Tallish &#39;160 is incorporated herein by reference. 
     U.S. Pat. No. 5,755,746 to Lifshey and Talish (hereafter “Lifshey &#39;746”); U.S. Pat. No. 5,626,554 to Ryaby, Talish and McCabe (hereafter “Ryaby &#39;554”); U.S. Pat. No. 5,556,372 to Talish, Ryaby, Scowen and Urgovitch (hereafter “Talish &#39;372”); and U.S. Pat. No. 5,520,612 to Winder, Talish and Ryaby (hereafter “Winder &#39;612”), entitled Locator Method and Apparatus, Gel Containment Structure, Apparatus for Ultrasonic Bone Treatment, and Acoustic System for Bone-fracture Therapy, respectively, provides ultrasonic apparatus and methods which are applicable to wound healing. Lifshey &#39;746, Ryaby &#39;554, Talish &#39;372, and Winder &#39;612 are incorporated herein by reference. 
     In general, an ultrasound carrier frequency between 20 kHz and 10 MHZ coupled with a relatively low-frequency modulating signal, such as 5 Hz to 10 kHz, and a spatial peak temporal average acoustic intensity, such as an intensity less than about 100 milliwatts/cm 2 , should aid in and should be effective in wound healing. 
     Heretofore, such techniques have not been applied to heal wounds by internal application of ultrasound, such as using reflection of ultrasonic waves by reflection from internal tissue such as bone. 
     SUMMARY 
     It is herein recognized that both longitudinally propagating ultrasound and shear waves generated by a transducer mechanism and/or by such longitudinally propagating ultrasound provide effective healing of wounds. 
     A portable therapeutic device and method of use thereof for healing a wound includes a transducer having an operative surface, with the transducer, disposed substantially adjacent to the wound to emit ultrasound to propagate in the direction of the wound for the healing thereof. Reflections of the ultrasound by bone tissue and by skin layers propagate toward the wound as longitudinal waves for the healing thereof, and shear waves are generated by the longitudinal waves and/or the reflected longitudinal waves for the healing of the wound. 
     The transducer may include an axis and a focusing element for focusing the propagation of the ultrasound at a predetermined angle with respect to the axis, with the focused ultrasound propagating toward the wound for the healing thereof. 
     Alternative configurations of the operative surface of the transducer include an annularly shaped operative surface for emitting the ultrasound therefrom, with the wound encircled by the operative surface for receiving the ultrasound and/or reflected ultrasound. 
     A housing may be provided for positioning the transducer substantially adjacent to a portion of the skin substantially adjacent to the wound, and for causing the portion of the skin to form a cavity, with the operative surface of the transducer disposed in the cavity to emit the ultrasound to an internal surface of the wound for the healing thereof. 
     Reflective media may be internally disposed within the body having the wound for reflecting the ultrasound from the transducer to propagate toward the wound for the healing thereof. Fixture structures, extending about a portion of the body having the wound, may also be provided for positioning the transducer substantially adjacent to the skin substantially adjacent to the wound. The fixture structure may include an adjustable strap. 
     In other embodiments, the transducer may be a rod-shaped operative surface having an axis for emitting the ultrasound radially toward the wound for the healing thereof. 
     Using the disclosed therapeutic devices, wounds are safely and simply treated, with such wounds as venous ulcers responsive to therapeutic ultrasound to be healed effectively. Such therapeutic devices and methods of use provide for wound treatment by modest adaption of existing devices for delivering ultrasound in therapeutic settings. 
     In one embodiment, a device is provided for delivering an ultra-high-frequency carrier signal for low power excitation of an acoustic transducer which is acoustically coupled to a limb or other part of a living body. The transducer is positioned adjacent an external skin location in the vicinity of the external border of the wound on the skin to provide a surgical, non-invasive transcutaneous delivery of at least part of its acoustic energy directed from the external skin location toward a portion of a bone located within the body in the vicinity of the boundary of the wound internal to the body. The boundary of the wound internal to the body is also referred to herein as the internal or interior surface of the wound. 
     Once the acoustic energy enters the body, it passes into internal body tissue and/or fluids. The acoustic energy, in the form of ultrasonic pulses, is reflected off the surface of underlying bone or other ultrasound reflective material, and the reflected ultrasound travels toward at least part of the internal surface or underside of the wound. Healing of the wound at the internal surface by the generation of epithelial cells is enhanced via the acoustic stimulation. 
     Preferably, a low frequency signal which is present as a modulation of the carrier frequency is transmitted from the ultrasonic transducer, through interposed soft tissue, and onto the surface of the bone. The carrier wave incident on the bone surface, or other reflection surfaces in the body, is reflected toward the internal surface of the wound. When the carrier wave impinges the internal surface of the wound, at least a portion of the carrier wave is converted into therapeutically beneficial shear waves of acoustic energy, flooding a region of the internal surface of the wound. The shear waves increase vascularization at the internal surface of the wound, thus enhancing growth of epithelial cells. The epithelial cell growth represents healing of the wound. The technique thus promotes healing of the wound from the internal surface of the wound. 
     The number, position, and size of ultrasonic applicators used at the external skin location are chosen based on the size and position of the wound, and the relative position and proximity of the bone from which the ultrasonic waves are reflected. One or more ultrasonic therapy treatments per day, each having a duration of approximately 20 minutes, is suitable. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The features of the disclosed therapeutic ultrasound apparatus and method will become more readily apparent and may be better understood by referring to the following detailed description of an illustrative embodiment of the present invention, taken in conjunction with the accompanying drawings, where: 
     FIG. 1 is a cut-away perspective view showing a device and method of use thereof for wound healing; 
     FIG. 2 is a side view of an embodiment of an ultrasound transducer; 
     FIG. 3 is a side cross-sectional view of the device using a focusing attachment; 
     FIG. 3A is a cut-away perspective view of an alternative embodiment of the transducer configured to have an annular shape and a woven fabric covering; 
     FIG. 4 is a frontal view of a typical wound disposed on a torso; 
     FIG. 5 is a cut-away perspective view of the wound healing device disposed near the wound in the torso; 
     FIG. 6 is a cut-away perspective view of the wound healing device applied to a wound in conjunction with a gel bladder; 
     FIG. 7 is a cut-away perspective view of the wound healing device causing an indentation of the torso to orient the transducer for healing the wound; 
     FIG. 8 is a cut-away perspective view of the wound healing device operating in conjunction with an internally disposed reflecting medium; 
     FIG. 9 is a cut-away perspective view of an alternative configuration of the wound healing device having an annular configuration and a woven fabric covering and operating in conjunction with an internally disposed reflecting medium; 
     FIG. 10 is a cut-away perspective view of an alternative configuration of the wound healing device having a rod-like configuration; 
     FIG. 11 is a cut-away perspective view of an alternative configuration of the wound healing device having an annular configuration without a woven fabric covering; and 
     FIG. 12 is a perspective view of an alternative configuration of the wound healing device attachable to a thigh for healing a wound thereupon. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now in specific detail to the drawings, with like reference numerals identifying similar or identical elements, as shown in FIG. 1, the present disclosure describes an apparatus  10  and method of use thereof for wound healing, which includes an ultrasonic generator  12  and one or more ultrasonic applicators  14 , which include ultrasonic transducers  16  known in the art, for applying ultrasonic waves  18 ,  20  to a wound  22 , such as an ulcer. More than one applicator  14  or transducer  16  may be used to stimulate larger wounds, as needed. The spatial peak temporal average acoustic intensity of the applicators  14  is between about 5 mW/cm 2  and about 100 mW/cm 2 . The carrier frequency and intensity of the ultrasonic treatment is selected by taking into account such factors as: (1) the amount of soft tissue interposed between the external skin location, where the ultrasonic applicator  14  is positioned, (2) the position and cross-section of the bone site  24  from which the ultrasonic waves  18  are reflected, (3) the amount of soft tissue interposed between the bone  26  and the internal surface  28  of the wound  20 , and (4) the size, topography and medical characteristics of the internal surface  28  of the wound  20 , and, consequently, shear waves or surface acoustic waves (SAW) and longitudinal waves to be generated at the site. 
     The carrier wave is modulated with an audio signal approximately between 5 Hz and 10 Khz. Low level ultrasound delivers a primary wave called the longitudinal wave  30 , which is emitted by the transducer  16  of the applicator  14  as shown in FIG.  1 . There are also shear waves or SAW  32  generated by the ultrasound from the transducer  16  which radiate outward along the skin surface. The primary longitudinal wave  30  is partially incident on a bone  26  in the body, and so is partially reflected at a reflection site  24  to generate a reflected portion  34 , with the reflected portion  34  directed toward the internal surface  28  of the wound  22 . The primary longitudinal wave  30  may also be reflected by other surfaces. For example, as shown in FIG. 1, the internal layer  36  of skin on the opposite side of a limb to the transducer  16  may provide a reflective surface to thus generate additional reflected longitudinal waves  38  directed from the opposite internal skin layer  36  to the wound  22 . 
     When the reflected longitudinal waves  34 ,  38  impinge on the internal surface  28  of the wound  22 , such reflected longitudinal waves  34 ,  38  are at least partially converted to shear waves or SAW  32  in and around the internal surface  28  of the wound  22 , which enhance wound healing at the internal surface  28  by stimulating cell production by the mesenchymal line, thus promoting vascularization and epithelialization. 
     As shown in the illustrative embodiment in FIG. 1, the ultrasonic applicator  14 , including the transducer  16  configured as a modular unit, is placed adjacent an external skin location  40  in the vicinity of the external border of the wound  22 . A gel bladder  42 , or alternatively a loose conducting gel or other ultrasound conducting media, is positioned between the transducer  16  and the external skin location  40 . As shown in FIG. 1, the ultrasound which is transmitted into the soft tissue medium in the form of longitudinal waves  30  diverges as it moves toward the bone  26  or other surfaces such as the skin layer  36  providing reflection. The reflected ultrasound, in the form of longitudinal waves  34 ,  38 , continues to diverge as it approaches the internal surface  28  of the wound  22 , so that the ultrasonic treatment delivered to the general site of the wound  22  covers a relatively large region of the internal surface  28  of the wound  22 . 
     Alternatively, as shown in FIG. 2, the transducer  16  may have an attachment, typically positioned between the operative surface  46  of the transducer  16  and the gel bladder  42 , which acts as a focusing element to focus the ultrasound emitted from the operative surface  46  into the soft tissue. In another embodiment, the transducer  16  may be configured to have the focusing element integrally formed with the transducer  16 . FIG. 3 shows a side view of the transducer housing of FIG. 2 showing the transducer  16  including the focusing element, illustratively embodied as the attachment  44 . Thus, the ultrasound emitted from the transducer  16  in the form of a primary longitudinal wave  30  may be directed at an angle  48  with respect to an axis  50  associated with the transducer and thence toward the bone  26  or other reflective surfaces when the ultrasound enters the soft tissue. The reflected waves  34 ,  38  also remain relatively focused. 
     The reflected longitudinal waves  34 ,  38  may generate respective sets of shear waves or SAW for providing a combined therapeutic treatment to the wound  22 . As shown in FIG. 3, the reflected longitudinal wave  34  created by reflection of the primary longitudinal wave  30  off the bone  26  is incident on a portion of the internal surface  28  of the wound  22 , thus creating a first set of shear waves  52 . The reflected longitudinal wave  38  created by the reflection of the primary longitudinal wave  30  off the opposite side layer  36  of tissue is incident on a separate portion of the wound  22 , thus creating a second set of shear waves  54 . In addition to this technique, the angle  48  of the ultrasonic emission may be swept and/or modified, either physically or electronically, so that different regions of the internal wound surface  28  may be treated. 
     In either technique, two or more transducers may be used, as determined by the size, length, etc. of the wound  22 . Generally, multiple transducers may be provided at a number of external skin locations around the wound  22  in order to increase the effectiveness of the ultrasonic therapy reflected to the internal surface  28  of the wound  22 . 
     In the illustrative embodiments of FIGS. 1-3, the ultrasonic head module of the ultrasonic applicator  14  includes the transducer  16  of an ultrasonic treatment apparatus. For clarity, the fixture structure which holds the head module adjacent the external skin location  40  is omitted. Also omitted are the electronics and other features which ultimately provide the excitation signals for the transducer  16 . These are described in further detail in the above-referenced patents and patent applications, which have been incorporated by reference. 
     Alternatively, or in conjunction, the at least one ultrasonic applicator  14  may be moved, or may be configured to be movable, to a different external skin location adjacent the wound  22  in order to provide treatment to various portions of the wound  22 . Varying the position of the at least one ultrasonic applicator, including moving the transducer  16  circularly or linearly along the skin, also provides treatment of varying intensity at portions of the wound  22 . 
     The transducer  16  itself may also be configured to vibrate with respect to a given external skin location, so that the longitudinal waves  30  generated therefrom and transmitted through the soft tissue are more uniform, thus providing more uniform treatment, including more uniform shear waves, at the internal wound surface  28  where the reflected longitudinal waves  34 ,  38  impinge. The transducer  16  may be made to vibrate with respect to a housing (not shown in FIGS. 1-3 for clarity) which holds the transducer  16  adjacent an external skin location to accomplish such uniformity of longitudinal waves  30 . 
     The focusing of ultrasonic waves described with respect to FIGS. 2-3 above is illustratively shown with a substantially planar operative surface  46  and a substantially conical attachment  44 . In alternative embodiments, the focusing of ultrasonic waves may be provided by configuring the transducer  16  with non-planar surfaces such as non-planar operative surfaces or non-planar segments to generate and emit ultrasound with different propagation characteristics in order to allow differing patterns and intensities of ultrasonic waves to be transmitted toward the internal surface  28  of the wound  22 . This provides a variety of therapeutic ultrasonic stimulation and treatment at the internal surface  28 . 
     For example, the transducer segments may be pie shaped, annular rings, or other configurations, which may be activated separately or in unison. Alternatively, or in conjunction, the transducer  16  may be provided with a modal converter or transducer lens, which may also change the pattern of the ultrasound emitted from the transducer  16 . 
     The carrier frequency and/or the modulating frequency may also be varied or swept through a range of frequencies in order to provide a variety of treatments to the internal wound surface  28 . The frequencies may be varied either in a continuous manner, or discrete changes may be made in the applied frequency. Varying the carrier and/or modulating frequency is especially useful in applying ultrasonic treatment to promote a variety of stages of cell regeneration in approximately the same region during the same therapy session. 
     In an alternative embodiment, FIG. 3A illustrates treatment of a wound  22  such as a venous ulcer as in FIGS. 1-3, but utilizing an annular-shaped transducer  56  having a curved operative surface  58  (shown in a cut-away perspective view in FIG. 3A) composed of a composite piezoelectric material attached by a connector  60  to an ultrasonic generator (not  9  shown in FIG.  3 A), in which the composite piezoelectric material disposed in a woven fabric  62  or a semi-permeable member provides ultrasonic conductivity between the transducer  56  and the skin of the patient. The woven fabric  60  may have either a hard or a pliable construction, and may be composed of material conductive of ultrasound. Alternatively, the woven fabric  60  may be porous for retaining and releasing ultrasound conductive gel. 
     The transducer  56  is cut or constructed to surround the external surface of the wound  22 . When the appropriate RF signals are applied, the composite piezoelectric material of the transducer  56  emits ultrasonic waves having the therapeutic parameters previously described. Primary longitudinal waves  64 ,  66  are emitted from the composite piezoelectric material into the body, as shown in FIG. 3A, and reflected from the surface of the bone  26  or from other reflective interfaces, to generate reflected longitudinal waves  68 ,  70 , respectively, which are directed onto the internal surface  28  of the wound  22 , thus creating therapeutic shear waves  72 ,  74 , respectively. It is understood that the composite piezoelectric material may completely surround the wound  22 ; thus, the primary longitudinal waves  64 ,  66  are emitted from around the entire wound, reflected from the reflecting material, and incident on the internal surface  28  of the wound  22 , thereby flooding the internal surface  28  of the wound  22  with the induced shear waves  72 ,  74 . 
     While the embodiments of the present invention described above refer to the reflection of a primary longitudinal wave from a bone to an internal surface of a wound, the present invention also encompasses delivery of ultrasound to the internal surface of the wound where there is no bone or other reflecting surface in the vicinity of the wound, as described below in further detail with reference to FIGS. 4-11. 
     FIG. 4 illustrates the front of a male torso  76  having a wound  78  on the stomach. The views illustrated in FIGS. 5-11 are cross-sectional views of FIG. 4 taken across lines  5 — 5 . As shown in FIG. 5, a transducer  80  is positioned in a transducer housing  82  disposed upon the external skin of the torso  76  adjacent to the external border of the wound  78 , and a longitudinal wave  84  emitted from the transducer  80  penetrates far into the body before it is reflected off a surface internal to the torso  76  such as the spine or any internal organs such as the lungs, stomach, or intestines, which may contain gases such as air, with reflected longitudinal waves then directed onto the internal surface  86  of the wound  78 . This is especially true when the person is overweight, or when the cross-section of available reflecting surfaces is small and/or uneven. The longitudinal wave  84  may provide some therapeutic healing of the wound  78 , but the intensity of the reflected wave incident on the internal surface  86  of the wound  78  may be too attenuated to provide the necessary therapeutic treatment. 
     FIG. 6 shows an alternative method and embodiment of treating such wounds of the torso  76 , in which a gel bladder  88  is interposed between the external surface of the wound  78  and the operative surface of the transducer  80 . The longitudinal wave  84  emitted from the transducer  80  travels directly through the gel bladder  88  and into the wound  78 , thus creating a shear wave  90  when the longitudinal wave  84  is incident on the internal surface of the wound  78 . The gel bladder  88  is to be sterile, especially if the wound  78  is open, and may be impregnated with medication, such as an antibacterial ointment, which flows into the wound  78  and/or its surface during the ultrasonic treatment. 
     FIG. 7 illustrates another method and device for treating the wound  78  of a torso  76 , in which the transducer  80  is pressed against the external surface of the lower torso, such as approximately adjacent the stomach, to be positioned near the wound  78 . By pressing the transducer housing  82  against the external region of the stomach, a local indentation  92  is created. The transducer housing  82  may be turned as it is pressed inward, so that the operative surface  94  of the transducer  80  is directed in the general direction toward the internal surface  96  of the wound  78  within the indentation  92 . As shown, the longitudinal wave  98  emitted is incident directly on at least a portion of the internal surface  96  of the wound  78 , thus inducing therapeutic shear waves  100 . If a specially configured transducer, or alternatively a transducer attachment  102 , is used, such as shown in FIG. 3, for focusing the ultrasound in a specific direction, the longitudinal wave  98  may be emitted off of a center axis  104  of the transducer  80 , for example, in a direction toward the internal surface  96  of the wound  78 , without the need for turning the transducer housing  82  as it is pressed against the skin. 
     FIG. 8 illustrates another method and device for treating a wound  78 , in which a reflecting medium  106  is inserted into the body in the proximity of the internal surface  96  of the wound  78 . The properties of the reflecting medium  106  provide for the reflection of the longitudinal wave  108  toward the internal surface  96  of the wound  96 , as if a bone were present, such as described above with reference to FIGS. 1-3A. The reflecting medium  106  may be composed of a variety of materials, and may be fixed in the body or inserted temporarily. For example, the reflecting medium  106  may be a metallic plate, a gas filled pouch, or other quasi-permanent inserts. The reflecting medium  106  may be also be, for example, a contrast agent composed of, for example, bubbles in a gelatin, which is injected intravenously prior to the treatment. In one embodiment, the contrast agent may be absorbable by the body in a relatively short period, thus the contrast agent acts as a temporarily inserted reflecting medium. 
     An inserted reflecting medium  106 , as described with respect to FIG. 8 above, performs particularly well in conjunction with a piezoelectric ultrasonic material or device. As shown in FIG. 9, the piezoelectric ultrasonic device  110  may be embodied as the device  56  described above with respect to FIG.  3 A. The piezoelectric ultrasonic device  110  may be configured to surround the exterior boundary of the wound  78 . As shown in FIG. 9, illustrative examples of the longitudinal waves  112 ,  114  generated from the piezoelectric ultrasonic device  110  surrounding the wound  78  are reflected off of an internally disposed medium  116  and onto the internal surface  96  of the wound  78 , thereby generating therapeutic shear waves (not shown in FIG. 9) at the internal surface  96  of the wound  78 . It is understood that the piezoelectric ultrasonic device  110  completely surrounds the wound  78 ; thus, longitudinal waves not limited to the illustrative examples of longitudinal waves  112 ,  114  are emitted around the entire wound  78 , reflected from the reflecting material  116 , and incident on the internal surface  96  of the wound  78 , to flood the internal surface  96  of the wound  78  with induced shear waves. 
     In an alternative embodiment shown in FIG. 10, an ultrasonic transmitting rod  118  is provided which emits at least one longitudinal wave  120  radially from the axis of the ultrasonic transmitting rod  118 . The rod  118  may be composed of, for example, a composite piezoelectric material, and the rod  118  is secured to the patient by a harness apparatus  122 ,  124  such that the rod  118  is pressed against the skin adjacent the wound  10 , and a portion of the longitudinal wave  120  is incident on the internal surface  96  of the wound  78 , thus inducing therapeutic shear waves (not shown in FIG.  10 ). 
     In another alternative embodiment shown in FIG. 11, an ultrasonic transmitting ring  126  is provided which emits longitudinal waves  128 ,  130  radially from the surface of the ring  126 . The ring may be composed of, for example, a composite piezoelectric material, and may be configured in a manner similar to the piezoelectric ultrasonic devices  56  and  110  in FIGS. 3A and 9, respectively, without the woven fabric to act as an ultrasonic conductor. Accordingly, ultrasonic conductive gel may be used with the ring  126  of FIG.  11 . With the ring pressed against the skin surrounding the wound  78 , a portion of the longitudinal waves  128 ,  130  emitted from the ring  126  is incident on the internal surface  96  of the wound  78 , thus inducing therapeutic shear waves  132 ,  134 . It is understood that the ring  126  may be configured to completely surrounds the wound  78 ; thus, longitudinal waves including the illustrative longitudinal waves  128 ,  130  are emitted from around the entire wound  78  and incident on the internal surface  96  of the wound  78 , to flood the internal surface  96  of the wound  78  with induced shear waves  132 ,  134 . 
     In an alternative configuration shown in FIG. 12, the wound healing device  136  includes a transducer  138  positioned in a housing  140  which is secured by an adjustable securing structure  142  to a thigh for healing a wound  78  thereupon, with the transducer  138  emitting longitudinal ultrasonic waves  144  which generate shear waves (not shown in FIG. 12) upon contact with the internal surface of the wound  78 . In an illustrative embodiment, the adjustable securing structure  142  shown in FIG. 12 includes an adjustable strap  146  having a first portion  148  engaging a second portion  150  using hook and link fasteners. Alternatively, a belt with a buckle and notches may be used, or a sterile adhesive strip for adhering to the thigh. 
     As noted above, the term “wound” as used herein, has a broad meaning, generally encompassing addressing damage to, repair of, or restoration of soft tissue. The present invention may be used, for example, to prevent surgical adhesions, by stimulating the proper repair of surgical incisions. It may also prevent or arrest wound dehiscence, by promoting vascularization at the surfaces adjacent surgical incisions. It may also be used in cosmetic surgery, for example, by enhancing the healing of hair transplants, or by directly stimulating regeneration of cells. 
     Accordingly, modifications such as those suggested above, but not limited thereto, are to be considered within the scope of the invention.

Technology Classification (CPC): 0