HK1164095B - Skin tensioner for hair transplantation - Google Patents

Description

Skin stretcher for hair transplantation

Technical Field

The present invention relates generally to devices, systems, and methods for applying tension to an area or surface of the skin, and in particular to skin stretchers and methods for use in connection with hair transplantation procedures.

Background

There are numerous surgical, cosmetic, therapeutic and dermatological procedures that involve manipulating an area of skin. Hair transplantation is one of those procedures and it typically involves harvesting a donor hair graft from a "donor area" and implanting it in a hairless area ("recipient area"). There are various known tools and instruments for harvesting and implanting follicular units ("FUs"), including various needles, perforators, and forceps. Hair transplantation is a very laborious and complex procedure requiring skill and precision. During a procedure performed manually by a physician, pressure is typically applied adjacent to the target location using two fingers in order to stretch the skin surface in the area where hair is harvested or implanted. Similar skin stretching techniques are used in various cosmetic and dermatological procedures other than hair transplantation.

An automated system for harvesting follicular units from a body surface is disclosed in U.S. patent publication 2007/0078466. In one embodiment, the skin stretcher in the form of two tines is pressed against the skin surface, thereby stretching the skin and enabling the FU to stand more upright relative to the scalp surface.

There are commercially available surgical retractors that hold tissue away from the operating field, including those manufactured by lonesstar Medical Products, Inc. However, these retractors are not well suited for skin stretching required for procedures such as hair transplantation.

Disclosure of Invention

The present application discloses various skin or body surface stretching devices and methods that can be applied to the scalp, skin or other body surface areas in various medical, cosmetic or dermatological procedures. Such devices are particularly useful, for example, in harvesting and/or implanting hair follicles or Follicular Units (FUs). In certain embodiments, the skin stretching device enables monitoring of the amount of stretch applied to the skin and adjustments thereto, as necessary. Furthermore, the disclosed stretching devices are relatively easy to apply by one person or one hand and can be easily removed and reapplied. Thus, the device can be easily removed from the treatment area to allow the patient to get up and move around in the middle of the procedure when needed. Another advantage of the various embodiments described herein is that the skin can be placed under substantially uniform or even tension across the treatment area. The device can be relatively inexpensive to manufacture and some parts can be disposable to facilitate cleaning and easily eliminate re-use of components for sterilization. In addition, the device may be provided with the ability to aspirate blood and flush with saline. In addition, the device may be provided with suction cups that hold the skin stretching device more firmly against the body surface. In combination with an imaging system, the stretching device may provide a platform for a reference point.

According to one aspect, a device for applying tension to a body surface includes a flexible frame including a skin contacting member having at least one skin grasper. The flexible frame is configured to move between a compressed configuration and a relaxed configuration due to the inherent flexibility of the frame. The flexible frame is also biased in the relaxed configuration, and in the relaxed configuration, the flexible frame is configured to provide tension in the body surface when the at least one skin grasper is engaged in the body surface. The frame may be inherently flexible due to the preferred selected material (e.g., an elastic material that is elastic in nature); and/or may be flexible due to shapes, structures, gaps, thicknesses, or other such design choices incorporated into portions of or into the overall frame that render the frame flexible. The body surface stretching device may apply a substantially uniform stretch across the body surface, or it may apply stretch in one or more directions across the body surface, depending on the embodiment and desired features. In other embodiments, the frame may comprise a plurality of (e.g., at least three) side sections, and compression of two of the at least three side sections causes at least three of the side sections to converge. Various skin graspers may include, for example, barbs, micro-barbs, adhesives, rough surface textures, or any other similar structures or features.

According to another aspect, a compression tool for use with a stretching device of the present application is provided. The compression tool is shaped and configured to engage a frame of the tension device and cause the frame to move between a compressed configuration and a relaxed configuration. The general plane of the compression tool (when positioned to engage the frame and move it between a compressed configuration and a relaxed configuration) may be substantially parallel to the general plane of the frame of the tension device, or it may be a different general plane, for example, substantially orthogonal to the plane of the frame.

According to yet another aspect of the invention, an apparatus for applying tension to a body surface includes a frame including a skin contacting member having a plurality of skin graspers, the frame configured to be operable to move between a compressed configuration and a relaxed configuration; and wherein when positioned on the body surface, in the compressed configuration at least one of the plurality of skin graspers is directed at a first angle relative to the body surface, and in the relaxed configuration the at least one of the plurality of skin graspers is directed at a second, different angle relative to the body surface. In some embodiments, the first angle may be substantially orthogonal to the body surface, and the second angle may be an angle different from substantially orthogonal to the body surface. Further, the frame may be a flexible frame operable to flexibly move between a compressed configuration and a relaxed configuration. The above device may be used with a compression tool such as described above, wherein the compression tool is shaped to engage the flexible frame and is configured to cause at least one of the plurality of skin graspers to move between a first angle and a second angle. Similar to the other described embodiments, the frame of the above device may generally lie in a first plane (including a curved plane), and the compression tool may be configured to be generally positioned in a second plane when the frame is caused to move between the compressed configuration and the relaxed configuration. The second plane may, for example, be substantially parallel to a general plane of the frame or substantially orthogonal to a general plane of the flexible frame.

According to yet another aspect, a device for applying tension to a body surface is disclosed. The device comprises a frame configured to move between a compressed configuration and a relaxed configuration, the frame comprising at least three contact members, each contact member having at least one skin grasper. The frame is further configured such that compression of two of the at least three contact members causes at least three of the contact members to converge into a compressed configuration. Thus, the frame may be conveniently compressed (manually or using a compression tool) with only one hand, and wherein the frame is configured to facilitate stretching of the body surface in the relaxed configuration when the at least one skin grasper is engaged in the body surface. The frame may be configured to conform to the body surface. In some embodiments, a first of the at least three skin contacting members may be in a first plane and a second of the at least three skin contacting members may be in a different plane than the first plane.

The features of the skin stretcher described with reference to one embodiment may be combined with one or more features described with reference to one or more of the other embodiments. Further, any of the described stretching devices may include at least one channel in the frame in fluid communication with one or more openings on a skin contacting member of the frame for placing the openings in fluid communication with a reduced pressure source for supplying suction to the skin. Alternatively, the stretching device may include, for example, an indicator on the frame that displays the magnitude of the stretching force; or a tension control on the frame that enables adjustment of the magnitude of the tension force.

Further, methods for applying tension to a body surface (for example, for use during hair harvesting and/or implantation) are disclosed. According to one aspect, the method includes using the inherent flexibility of a flexible frame to move the flexible frame from a relaxed configuration to a compressed configuration. The flexible frame may include a skin contacting member having at least one skin grasper; and the method further comprises placing the skin contacting member of the flexible frame on the body surface such that the at least one skin grasper engages the body surface; and releasing the flexible frame to cause the frame to move from the compressed configuration to the relaxed configuration so as to create tension across a treatment area in the body surface. According to another aspect, a method of applying tension to a body surface may include compressing a frame of a tension device in N directions to cause the frame to compress in more than N directions. According to yet another aspect, a method of applying tension to a body surface may include moving a frame of a tensioning device from a compressed configuration to a relaxed configuration so as to cause at least one skin grasper positioned on the frame to move from a first angle relative to the body surface to a second angle relative to the body surface. Any of the methods described herein may further include engaging the flexible frame using a compression tool and causing the flexible frame to move between the compressed configuration and the relaxed configuration. Similarly, any of the methods may comprise harvesting hair grafts from the body surface in the treatment area or implanting hair grafts into the body surface. As will be understood from the detailed description, one or more steps of the various methods of applying stretch to a body surface described herein with reference to different embodiments may be combined together or otherwise performed in the same method.

Drawings

The features and advantages of the invention described herein will become apparent and more readily appreciated as the same becomes better understood by reference to the specification, claims and appended drawings, wherein:

FIG. 1 is a perspective view of a first embodiment of a skin stretcher having a closed-loop frame, a plurality of independently adjustable skin contacting members, and a stretch control mechanism;

FIG. 2 is an enlarged perspective view of one example of the skin engaging member shown in FIG. 1;

FIGS. 3A and 3B are perspective and side elevational views of an alternative skin contacting component that may be used with the skin stretcher;

FIGS. 4A and 4B are perspective views of a skin contacting member that may be used with a skin stretcher incorporating suction cups and barbs;

FIGS. 5A and 5B are perspective views of an alternative skin contacting member incorporating a suction cup and a skin grasper, such as a barb;

FIG. 6A is a perspective view of an alternative skin stretcher having a compass-like frame with bifurcated legs each having a skin contacting member thereon incorporating suction cups and barbs;

FIG. 6B is an enlarged perspective view of the bottom side of one of the skin contacting components from FIG. 6A;

FIG. 7 is a perspective view of a skin stretcher having a helical spring frame with bifurcated legs each having a skin contacting component incorporating barbs thereon;

FIG. 8 is a perspective view of a skin stretcher having a compass-like frame with bifurcated legs each having a skin contacting component incorporating barbs thereon;

fig. 9A and 9B are perspective views of a butterfly skin stretcher frame shown in inwardly compressed and relaxed views, respectively;

fig. 10A and 10B are top and bottom perspective views, respectively, of a fluid irrigation alternative butterfly skin stretcher frame incorporating a fluid rinse to remove blood from an operating field;

FIGS. 11A and 11B are perspective views of yet another alternative butterfly skin stretcher in conjunction with a compression tool;

FIG. 11C is a perspective view of another alternative skin stretcher;

FIG. 11D is a perspective view of the alternative skin stretcher of FIG. 11C along with an alternative compression tool;

12A and 12B are top and bottom perspective views, respectively, of yet another alternative skin stretcher having a closed loop frame and four contact members each incorporating a skin grasper;

FIG. 13 is a top perspective view of yet another alternative bodyside tensioner in a relaxed configuration;

14A and 14B are top and bottom perspective views, respectively, of an alternative butterfly skin stretcher frame incorporating grooves for additional fastening and stretching devices;

15A and 15B illustrate that the angle of the barbs relative to the body surface is substantially the same when the frame is both compressed and relaxed;

16A and 16B illustrate the angle of the barbs relative to the body surface being a first angle when the frame is compressed and an angle different than the first angle when the frame is relaxed; and is

Fig. 17 is a perspective view of yet another alternative body surface stretching device.

Detailed Description

In the following detailed description, reference is made to the accompanying drawings that show, by way of illustration, specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as "top," "bottom," "front," "back," "side," "distal," "proximal," etc., is used with reference to the orientation of the figures being described. Because components or embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

It has been found that commercially available surgical retractors (such as those manufactured by lone star medical products) do not provide uniform and consistent skin stretching across the treatment area. Furthermore, if the patient needs to rest, it is difficult to install, remove and reinstall. The present application describes a number of systems and methods for creating stretch across the skin or body surface to facilitate various procedures on the body surface, such as harvesting of Follicular Units (FUs). For clarity, creating stretch in the skin surface means applying a stretching force such that the skin surface exhibits a lateral stretch that is greater than any stretch present in a relaxed state. Typically, this requires pulling at least two spaced apart locations apart or applying a separating force to the two locations, with the middle region undergoing stretching. It is understood that the stretching may be unidirectional (along a single axis) or multidirectional and even omnidirectional. For example, a circular frame that pulls the skin surface equally apart in all directions sets an omnidirectional stretch in the inner circular region.

To apply a stretching force to the skin surface, the systems described herein incorporate at least two or more spaced apart skin contacting members. The skin contact members each define a skin contact surface to be laid flat against the skin surface. The skin contacting surface features some means of holding the skin contacting member to the skin surface, such as suction cups in certain embodiments. However, in order to hold the skin contacting component to the skin surface, the system only needs to increase the lateral resistance to the movement of the skin contacting component across the skin surface from the resistance required to move the bottom smoothing component across the skin surface in the absence of any external downward pressing force.

One way to increase the lateral resistance to movement of the skin contacting element is to provide barbs on the skin contacting surface. In the context of the present application, "barb" means any small element protruding from the skin contacting component below the skin contacting surface to penetrate the skin surface or form a depression in the skin surface. That is, the barbs do not necessarily have to be sharp in order to be able to penetrate the skin surface. Thus, the term "barb" incorporates needles, pins, spikes, hooks, nubs, protrusions, and other similar terms. Furthermore, in certain embodiments and applications of the present invention, it may be beneficial to use the term "micro-barbs". The term "microbarbs" refers to small barbs having the largest size characteristic (typically their diameter (or cross-sectional dimension; reference to diameter in this context does not mean that the cross-section must be circular).

Although barbs are described herein as the primary means of ensuring a good grip of the skin contacting member to the skin, other solutions that merely increase the coefficient of friction are also contemplated. For example, skin contacting components with adhesives may be successfully utilized in connection with certain aspects described herein. Another possibility is to mate Velcro patches, one of which is temporarily adhered to the skin and one on the skin contacting part. As such, the term "skin grasper" as used herein encompasses various means of holding the skin contacting component to the skin surface by increasing the lateral resistance to movement of the skin contacting component across the skin surface relative to a smooth surface of the base. That is, "skin grasper" encompasses barbs, micro-barbs, suction cups, adhesives, velcro, ribs, ridges, pins, etc., and even rough surface textures. While the presence of one or more of such structures on items secured to the skin may be known theoretically (e.g., adhesive bandages), it is believed that their use in conjunction with inducing stretch across the treatment area is novel, particularly in the context of hair transplantation. Furthermore, various other features of the skin stretcher described herein in connection with one or more of these skin graspers are believed to be novel.

With reference to a system or process, the adjective "automated" generally means that some portion or all of a particular system or step in the process involves an autonomous mechanism or function; that is, the mechanism or function does not require manual actuation. Finally, one or more steps in the procedure may be automated or autonomous, with some portions requiring manual input. This definition encompasses automated systems that only require an operator to press an ON switch or schedule the operation, and also encompasses systems in which a handheld tool is used but some mechanism of the system functions autonomously (i.e., without human input) to perform a function. Some automated processes may also be robot-assisted or computer/software/machine instruction controlled. The apparatus and method of the present invention are useful in both manual procedures and systems, as well as in automated procedures and systems, and are particularly useful in robotic assistance systems and procedures. In contrast, when referring to using a particular component of a system or a particular step in a process, the adverb "automatically" means that this step is accomplished autonomously, i.e., without real-time manual assistance. The terms "coupled" or "attached" or "connected" or "mounted" as used herein mean directly or indirectly coupled, attached, integrated, or mounted, e.g., through one or more intervening components.

According to one aspect of the present application, a skin stretcher is provided that allows for control of stretching and provides substantially uniform stretching across an associated treatment area. In a first embodiment of the present application, FIG. 1 illustrates a skin stretcher 20 having a closed loop frame 22 and a plurality of independently adjustable skin contacting members 24. In this embodiment, the frame 22 features a generally square inwardly-facing wall 26 that defines the periphery of a similarly-shaped aperture into which the skin contacting component 24 protrudes. A plurality of skin contacting members 24 are shown protruding from each of two opposing parallel sides of the wall 26, but they could be provided in all four sides. Furthermore, as will be apparent from the description of the alternative embodiments, the frame 22 need not be a closed loop, nor does it need to define a linear aperture or have an even number of sides. For example, the apertures may be circular or elliptical or triangular.

The frame 22 provides a structure to which the movable skin contacting element 24 is mounted and provides rigid support for the contacting element. Fig. 1 illustrates three skin contacting members 24 protruding inwardly from each of two opposing parallel sides of the frame interior wall 26. As will be explained below, the frame 22 is designed to be placed on a skin surface with the skin contact member 24 applying tension to or stretching the skin within the frame aperture. That is, each skin contacting element 24 extends inwardly from the frame 22, contacts and is secured in some manner to the skin surface, and applies an outward force parallel to the skin surface toward the external frame.

In one particular embodiment, as seen enlarged in fig. 2, each of the skin contacting members 24 may include a barb or hook 28 on the distal end of the finger 30. In turn, each finger 30 is connected to an elongate flexible strand 32 (or alternatively a wire 32) that passes outwardly through an opening in the inner wall 26 of the frame. Barbs or hooks 28 may be inserted through incisions formed in the skin surface so that the skin contacting component 24 may exert a stretch when subjected to an outward force. Alternatively, the hook 28 may have a sharp tip adapted to penetrate the skin surface, making a previously formed incision unnecessary. Also, instead of directly engaging the skin surface, the hook 28 may engage a different skin contacting member and thus may serve only as a link in the overall stretching mechanism.

The skin stretcher 20 incorporates a mechanism for controlling the outward force on each of the skin contacting members 24. In the illustrated embodiment, each flexible strand 32 extends outwardly through an opening in the frame 22. There are numerous ways to apply outward forces to the flexible strands 32 and in turn to the skin contacting element 24. For example, each flexible strand 32 may be elastic and secured to the frame 22 such that it may be stretched prior to engaging the corresponding barb or hook 28 with the skin surface. In the illustrated example, each flexible strand 32 passes through a tension adjuster 40 mounted in the frame 22 or provided as a separate element on the exterior of the frame as shown. In a simple embodiment, each stretch adjuster 40 comprises: a housing 42 having a through bore for receiving the strand 32; and a knob 44 connected to a shaft (not shown) intersecting the through bore that applies friction to the strand in the through bore. For example, the knob 44 may be connected to a threaded shaft that is received in a similarly threaded bore in the housing 42 so that the shaft can be tightened onto the strand 32 in the manner of a set screw. The free ends of the strands 32 can be manually pulled outward until a desired tension is established in the skin surface, at which point the user actuates the knob 44 to secure the position of the strands relative to the housing 42 and frame 22. In this regard, the strands 32 may be elastic as mentioned above or relatively inelastic, such as stainless steel wires. In either case, engaging the skin contacting elements 24 with the skin surface and pulling outward creates tension in the skin surface.

In an alternative embodiment, each or either of the tensioning adjusters 40 incorporates an internal reel or friction wheel (not shown) for pulling the associated flexible strand 32. For example, the flexible strands 32 may be wound on a reel that is rotated by the knob 44. This provides the user with greater control over the amount of stretch in the flexible strands.

According to another aspect of the present application, the skin stretcher 20 may indicate the amount of stretch in each of the flexible strands 32, for example. For example, in the just described embodiment of the stretch adjuster 40 having a spool, the knob 44 may have indicia so that the number of rotations can be monitored, with the level of stretch being relative to the degree of rotation. In the illustrated embodiment, a shaft depending from each knob 44 engages the associated flexible strand 32 through a linear slot 50 in the housing 42. A pin 52 connected to the flexible strand 32 or knob 44 translates within another linear slot 54 in the frame 22. The pins 52 are spring biased outwardly within the slots 54 and translate inwardly along the slots 54 as the tension in the flexible strands 32 exceeds the spring bias. Thus, as the pins 52 move inwardly, they provide a visual indicator of the amount of stretch in the flexible strands 32. Calibrated indicia may also be provided next to and along the slot 54.

Of course, there are numerous other ways to indicate stretch in the flexible strands 32, such as analog or digital numerical force displays that are more complex and often more expensive. This application covers any number of indicators from the simplest to the most complex. Further, either or both of the stretch control mechanism and stretch indicator may be incorporated into any of the skin stretchers described herein, and the absence of an illustrated stretch indicator or stretch control should not be understood as not including a stretch indicator or stretch control. The stretch indicator helps the user establish the proper skin stretch. A minimum level of stretch is desirable, particularly for hair follicle removal to smooth the skin surface and encourage follicular units to stand upright. Furthermore, the predetermined minimum level of stretching helps the removal tool, such as a needle, to pierce the skin without having to cut away an excessive piece of skin around the follicular unit. However, the stretching should be limited to a maximum value to avoid excessive trauma of the skin surface. Finally, an indicator of stretch in each flexible strand enables the user to balance the amount of stretch to avoid applying too much stretch to one location or another.

Fig. 3A and 3B are perspective and side elevation views of an alternative skin contacting component 60 that may be used with the skin stretcher described herein. As mentioned above, it may be beneficial to eliminate or reduce wounds that may result from the use of certain barbs, such as the hooks 28 shown in fig. 2. Furthermore, in some applications, the use of a small number (e.g., 6 to 10) of relatively large hooks 28 may not provide a sufficiently uniform stretching of the skin throughout the treatment area. For example, skin stretching in the area around the location of the hooks may be sufficient, but in the space between the hooks, the skin may not be stretched or stretched enough for such procedures as hair harvesting and implantation. Alternatively, the stretch established by relatively few spaced hooks may be unequal, resulting in sub-optimal stretch in some areas. Thus, the hook 28 of fig. 2 may be avoided altogether or it may simply serve as an intermediate link to alternative skin contacting components (e.g., those shown at 60 in fig. 3A). While the present invention contemplates other ways to couple or connect the flexible strands 32 to the skin contacting member 60 without the use of the hooks 28, the hooks 28 on the skin contacting member 24 described previously may be used because they enable the entire frame 22 to be quickly removed. Further, the hook 28 (or similar expedient) is universal and coupled to any number of different skin contacting components.

An example of the skin contacting member 60 includes a coupling body 62, the coupling body 62 having a generally horizontal flange 64 extending therefrom, the generally horizontal flange 64 defining a skin contacting surface 65 on a bottom thereof. The coupling body 62 includes an upper tapered bore 66, the upper tapered bore 66 leading to a bore 68 that can be engaged by the hook 28 or other alternative connector 28. The tapered shape of the aperture 66 aids in rapid insertion of the connector 28. Flange 64 includes a plurality of perforations or bores 70 through which a plurality of microhooks or microbarbs 72 (as described below) pass, the microhooks or microbarbs 72 having sharp ends that project below skin contacting surface 65 and form a more uniform spread by distributing force across a larger area of skin. As an additional benefit, the micro-barbs 72 are desirably sized so as to eliminate or reduce the formation of wounds requiring healing. In the illustrated embodiment, bore 70 is angled downward in the proximal direction to enhance the ability of microbarbs 72 to anchor in the skin surface, however the angle of the bore is not limited to the illustrated angle. The micro-barbs 72 may be straight pins or needles that are easily inserted and secured within the bore 70, such as with a suitable adhesive. Alternatively, the micro-barbs 72 may be curved or angled and may be fixed in the material of the flange 64 during the molding process. The reader will appreciate that there are numerous ways to provide downwardly projecting micro-barbs on the skin contacting element.

There is at least one barb 72 provided on the skin contacting member 60, but preferably a plurality of barbs are included to enhance the gripping effect on the skin surface. Furthermore, increasing the number of barbs 72 desirably is combined with a reduction in their size. In a preferred embodiment, there are at least four and preferably ten or more barbs 72 (which will be referred to herein as "micro barbs," as explained previously). Furthermore, the length that the micro-barbs 72 extend below the skin contacting surface 65 is desirably less than about 5mm and preferably between 1mm and 4 mm.

As mentioned above, "barbs" and "microbarbs" are examples of various "skin graspers" or "skin bites," which should be understood to encompass any number of downward projections from the skin contacting surface 65. Such downward protrusions may be, for example, molded spikes, pins, or ribs on the underside of the skin contacting member 60. The use of sharp elements such as barbs 72 that pierce the skin surface is only one alternative.

In use, with reference to the example illustrated in fig. 1, a user positions two or more of the skin contacting members 60 in a spaced apart relationship on the skin surface and applies a stretching force tending to separate the members. For example, six skin contacting members 60 may be used in conjunction with the skin stretcher 20 illustrated in fig. 1, with six hooks 28 attached to respective coupling bodies 62. Pulling the flexible strands 32 from the frame 22 places the skin surface between the two rows of three skin contacting elements 60 in tension.

According to another aspect of the present application, fig. 4A and 4B are perspective views of a skin contacting member 80 that may be used, for example, with the skin stretcher 20 of fig. 1 or other variations and incorporates suction cups and barbs. The skin contacting element 80 includes a central coupling body 82 and a pair of oppositely directed flanges 84. A tension applying member 86 is coupled to an upper surface of the coupling body 82. The member 86 may, for example, be identical to the skin contacting member 24 described above with respect to fig. 1 and 2, and thus may include a finger 88 having a distal barb 90 and a flexible strand 92 extending in a proximal direction. The hook 90 may engage a small aperture 94 or other similar feature in the top surface of the coupling body 82. Alternatively, the member 86 may have a connector 90 (rather than a hook), or it may be otherwise mounted or connected to the skin contacting member 80.

The flanges 84 each have a skin contacting surface 96 on an underside thereof, with a plurality of micro-barbs 98 projecting from the skin contacting surface 96. In the illustrated embodiment, there are ten such micro-barbs 98 on each flange 84, all angled downward in the proximal direction. The flange 84 and the micro-barbs 98 may be similar to those described above with respect to fig. 3A and 3B. The barbs and micro-barbs may be arranged in multiple rows, or they may be staggered to achieve higher density. Further, some of the barbs may have different depths than others, for example, the depth of a barb may be approximately in the range between 1mm and 4 mm. For example, one row of barbs may have the same depth of 1mm, while another row of barbs may have a depth of 2mm or more than 2 mm.

In addition to the micro-barbs 98, the suction cup also enhances resistance to lateral movement of the skin contacting member 80 across the skin surface. More particularly, as seen in fig. 4B, the underside of the coupling body 82 includes a hollow foot 100 defining a central cavity. A nipple 102 projecting upwardly from the top of the coupling body 82 provides access to the central cavity. The tube or conduit transmits reduced pressure or suction into the central lumen via the adapter 102. Since the hollow foot 100 extends approximately as far as being flush with the skin contacting surface 96 of the flange 84, it also contacts the skin surface to form a seal and form a vacuum within the central cavity. The hollow foot 100 may be formed of a resilient material to enhance sealing.

Fig. 5A and 5B show another skin contacting member 110 that is nearly identical to the member 80 described above. Where the member 80 is generally rectilinear with proximally and distally directed flanges 84, the skin contacting member 110 is generally circular in plan and has a cylindrical coupling body 112 surrounded by a circular outer flange 114. An array of circular barbs or micro-barbs 116 extend downwardly from the skin contacting surface 118 on the underside of the flange 114. A hollow tubular foot 120 projects downwardly in the space within the coupling body 112 to the level of the skin contact surface 118. Likewise, a suction tube may be connected to the upper tube fitting 122 to create a vacuum within the tubular foot 120 against the skin surface.

In one variation, the tubular foot 120 may be divided into multiple pockets, each pocket having its own vacuum attachment and being connected to its own suction port or tube fitting 122 (alternatively, there may be one suction port and some sort of selector to open fluid communication with different pockets). In this manner, rather than forming a vacuum over the entire surface area of tubular foot 120 (and possibly causing bleeding in the case of a prolonged procedure, resulting in a "bruised" bluish purple spot), multiple vacuum areas may be formed and repeatedly and/or sequentially opened and closed to avoid prolonged pressure on a particular skin surface portion within the same cavity.

Sometimes, the stretch applying member 86 (fig. 4A) pulls the skin contacting member 110 in a manner that it can cause the skin contacting member 110 to rotate or angle relative to the skin surface. To mitigate this effect, a small hole or opening 117 may be provided proximate to the barb 116, as shown in fig. 5B. An elastic tube or similar pulling connector may be attached through the hole 117 and connected to the tension applying member 86 to apply force to the skin contacting member 110 at the lower portion without creating a moment or rotation.

Fig. 6A is a skin stretcher 130 different from that described above, having a compass-like frame 132 with bifurcated legs 134 each having a skin contacting member 136 thereon that incorporates both suction cups and barbs. The frame 132 includes a pair of base members 140a, 140b pivotally connected about a vertical axis 142. Although not shown, the frame 132 preferably incorporates springs or other such biasing members intermediate the base members 140a, 140b (as shown, for example, in fig. 8) that tend to spread them apart.

Fig. 6B is an enlarged perspective view of the bottom side of one of the skin contacting members 136 from fig. 6A. Each of the legs 134 is a hollow tubular member having a plurality of ports 144 leading to a central lumen. Each of the ports 144 opens at a plenum 146 defined within the associated skin contacting member 136. The plenum chamber 146 opens downwardly in the skin contacting surface 148. The proximal end of each of the tubular legs 134 terminates in a tube fitting 150 to which a suction tube may be attached. By placing the skin contacting surface 148 on the skin surface and providing suction to the lumen of the tubular leg 134, a vacuum may be created within each of the plenum chambers 146, thereby holding the skin contacting member 136 against the skin surface.

As mentioned, the furcation frame 132 includes springs or other mechanisms for spreading apart the base members 140a, 140b and, in turn, the skin contacting member 136. To enhance the ability of the skin contacting member 136 to be held to the skin surface, an array of barbs 152 is provided in each. In the illustrated embodiment, there are ten barbs 152 projecting below the respective skin contacting surface 148 of each skin contacting member 136, but this number may be as small as one and greater than ten. The barbs 152 desirably are directed downwardly and at an angle from the opposing skin contacting component 136. More particularly, as seen in fig. 6B, each of the barbs 152 is angled relative to a vertical midplane 154. Angling the barbs 152 in one skin contacting component 136 with the other skin contacting component 136 enhances their ability to anchor to the skin surface and create tension therein.

Fig. 7 shows a skin stretcher 160 that is nearly identical to the device of fig. 6A in that it incorporates a frame 162 with bifurcated legs 164. The central member of the frame 162 includes a coil spring 166 that acts as a pivot for the leg 164 and provides a return spring force to the leg 164 if it is displaced from the relaxed configuration. In one embodiment, the relaxed configuration is shown with the distal portions of the legs 164 extending parallel, although other arrangements are possible.

Each of the bifurcated legs 164 terminates at a distal end in a skin contacting component 170 incorporating a barb 172 projecting below the lower skin contacting surface. As with the earlier embodiments, the barbs 172 in one or more of the skin contacting components 170 may be angled downward and into the other skin contacting component. The skin stretcher 160 shown in fig. 7 does not contain suction cups, but those skilled in the art will appreciate that suction cups can be provided that are nearly identical to the earlier described embodiments. In use, the user squeezes the bifurcated legs 164 towards each other prior to pressing the skin contacting element 170 against the skin surface. The resulting outward spring bias formed by the coil springs 166 tends to spread the skin contacting members 170 apart (as shown by the arrows) and apply tension to the skin surface therebetween.

Fig. 8 illustrates another skin stretcher 180 also having a compass-like frame with bifurcated legs 182 each having a skin contacting member 184 thereon. As with the embodiment of fig. 6A, the frame includes a pair of base members 186A, 186b arranged to pivot about a vertical axis 188 and biased apart by a spring 187 positioned in the space therebetween. The two side walls 189 of the gap provide a hard stop to set a minimum spacing between the legs 182 thereon and the skin contacting member 184. The user squeezes the base members 186a, 186b together until the side walls 189 touch, applies the spaced apart skin contacting members 184 to the treatment area, and releases the frame. The spring 187 applies an outward force to the base members 186a, 186b that creates tension across the treatment area between the skin contacting members 184. The strength of the spring 187 and the degree to which it is compressed is calibrated to establish the desired tensile force.

Each of the skin contacting members 184 includes an array of barbs or micro-barbs 194 that project downwardly from the skin contacting surface 192. The skin contacting surface 192 is angled to better conform to a curvilinear surface, such as the patient' S scalp (S shown in phantom), as compared to the earlier embodiments. More specifically, each of the skin contacting surfaces 192 forms an angle with a horizontal line drawn across the distal end of the skin contacting member 184 and generally in a horizontal plane perpendicular to the vertical axis 188. The skin contacting surface 192 may be planar or may also be slightly concave.

Fig. 9A and 9B again illustrate a skin stretcher 200 with a closed frame 202 that is somewhat similar to a butterfly and is referred to as "butterfly". Fig. 9A shows the frame 202 having been compressed or collapsed inward, while fig. 9B shows the frame in a relaxed configuration after the external force is removed. The frame 202 is flexible and generally in a plane and preferably comprises a single element, typically of molded material, and is configured such that it can be compressed inwardly from a relaxed position. In one embodiment, the frame may comprise a resilient material that is elastic in nature. In another embodiment, flexibility may be obtained by structure, shape, gap, thickness, and/or material selection, for example, incorporated into portions of or into the entire frame.

In the illustrated example, the flexible frame 202 includes four side sections 204 joined by four spring corners 206 that project diagonally outward from the side sections. Any other even or odd number of side sections and spring corners of the frame are within the scope of the invention, so the following description refers to four side sections for illustration purposes only. The four side sections 204 are shown as being linear and arranged generally in a square, but they may be arcuate and otherwise arranged in various geometric patterns. In the illustrated embodiment, each of the four spring corners 206 has a thin beam 208 and a thick beam 209 extending outwardly from two adjacent side sections 204 and joined by an arcuate bridge 210. The spring corner essentially has a spring portion consisting of a narrower and flexible beam 208 and a bridge 210 and a second (basic) beam 209.

Fig. 9A shows the four side sections 204 displaced inwardly toward each other such that the gap between each pair of cross beams 208 tapers or narrows. In this manner, the length of cross beam 208 and the material and shape of arched bridge 210 make frame 202 highly flexible. In contrast, in the relaxed configuration of fig. 9B, the gap between each pair of cross beams 208 is substantially constant. It should be noted that the user compresses the frame 202 by squeezing two of the side sections 204 together (which also causes the vertical side sections to converge toward the center by virtue of their inward concavity as indicated by inward arrows 211). It can be seen that the opening formed by the side sections 204 is smaller when the frame 202 is in its compressed state than in its relaxed state.

Each side section 204 features a plurality of perforations 212 for receiving barbs or micro-barbs (not shown) as described above. Fig. 9A and 9B are both bottom views of the frame 202 illustrating the skin-contacting surface 214 on the bottom of each of the side sections 204. The barbs extend beyond the skin contacting surface 214 and provide an anchor on the skin surface for each of the side sections 204. In some embodiments, the frame 202 may be made of, for example, metal to be reusable, while the barbs and microbarbs may be made disposable to be glued or otherwise temporarily attached to the reusable frame. For example, a clip having a plurality of barbs (e.g., pins) may be removably attached to the frame or to a skin-contacting surface. Another variation is to use adhesive or velcro to temporarily attach the barb array to the frame surface. Furthermore, various fiducial points visible under image guidance may be similarly attached to the frame, thus providing a convenient reference framework for aiming follicular unit removal or implantation tools.

During a skin stretching procedure, the user compresses the frame 202 into the configuration shown in fig. 9A by squeezing the two opposing side sections 204 (as mentioned, the other two sides are also bowed inward) in the direction of arrow 211. Accordingly, a method of applying tension to a body surface may include compressing a frame of a tension device in N directions (e.g., N-2) to cause the frame to compress in more than N directions. More specifically, the method can include compressing a frame of a stretching device into a compressed configuration, the stretching device having at least three contact members, each contact member having at least one skin grasper; and releasing the frame into a relaxed configuration; wherein compressing the frame comprises compressing two of the at least three contact members to cause the at least three contact members to converge; and wherein releasing the frame into the relaxed configuration comprises facilitating stretching of a body surface while engaging the at least one skin grasper therein.

Since the opposing side sections 204 are arranged in a generally square shape, eventually the four side sections 204 will be prevented from moving further when the corners of the side sections 204 meet each other. However, improved stretching may result if the opposing side sections 204 are arranged to form a rectangular configuration, with the opposing side sections 204 extruded in the direction of arrow 211 being shorter than the other opposing sides 204. Altering the dimensions of the opposing sides in this manner may enable, for example, the end perforations 216 and 217 on the opposing side sections 204 to move inward until they reach the point where the perforations 215, 216, 217, and 218 form a substantially straight line. In this way, the perforations may be configured to form a rectangular arrangement of equidistant perforations (even at the corners), thus facilitating more uniform stretching. The four side sections 204 may then be pressed onto the skin surface surrounding the treatment area so that the barbs (or similar skin grasper expedients) engage the skin surface. After releasing the frame 202, the four side sections 204 are biased outward by the resilience of the spring corners 204, thus placing the skin surface in tension. Due to the configuration of the illustrated frame 202, the stretching is primarily biaxial, but other shaped frames (e.g., circular, hexagonal, triangular, etc.) may be utilized to achieve more omnidirectional stretching. The device of the present invention may be made of a variety of materials, including metal or plastic. It can also be made disposable.

Fig. 10A and 10B are top and bottom perspective views, respectively, of an alternative butterfly skin stretcher 220 incorporating a fluid flush to remove blood from an operating field. The elements of the frame 222 of the stretcher 220 are similar to those described above with respect to fig. 9A and 9B and will not be repeated. Of course, the reader will understand that fluid irrigation can be incorporated into any of the skin stretcher designs described herein.

At least one of the side sections 224 of the frame 222 includes a fluid flow channel therein. The salt or other inert fluid may be supplied through ports 226 in the side sections and distributed to the treatment area within the frame 222 through the side sections 224, or distributed from around the periphery of the treatment area through all of the side sections. The fluid lavage fluid will mix with any blood or other fluid in the treatment area and the suction port 228 in the side section 224 provides suction to remove excess fluid. In this regard, the lateral recesses 230 in the bottom side of the side section 224 provide reservoirs that distribute suction along one side of the treatment area so as to create a gradient to more effectively draw in excess fluid. One particularly advantageous feature of the embodiment shown in fig. 9A, 9B, 10A and 10B is that it allows one-handed operation of the device by pushing, for example, two sides 222 with a thumb and finger, which results in all four sides moving correspondingly.

Fig. 11A and 11B illustrate an alternative butterfly skin stretcher 240 along with an auxiliary device or tool 242 that facilitates its deployment. As previously described, the skin stretcher 240 may generally lie in a plane and include, for example, a frame having four side sections 244 that are engaged by four spring corners 245 that project diagonally outward therefrom. Each side segment 244 features a skin contacting surface 246 on which a skin grasper (e.g., a plurality of barbs or micro-barbs 248 as described above) is positioned. The reader will note the dimpling of the underside of the frame of the skin stretcher 240, which helps to conform or wrap the skin contacting surface over the convex skin surface.

With a relatively small sized butterfly frame, the user may experience difficulty compressing the frame while positioning the frame over the treatment area and pressing downward to engage the barbs. Thus, the compression tool 242 may be utilized to simplify the procedure. One example of the compression tool 242 illustrated in fig. 11A and 11B includes a compass-like clamp having two diverging legs 250 connected at a hinge 251. The distance between the two bifurcated legs 250 may be reduced to accommodate a smaller hand or sized in a manner suitable for the user. The free ends of the legs 250 terminate in blocks 252, in this example, each of the blocks 252 is shaped to fit over an outer edge of one of the side sections 244; while conformability is beneficial for a better fit, it is not necessary. In the illustrated embodiment, the blocks 252 each have a convex groove 256 that receives a concave lip 254 on the opposite side section 244. In use of this particular configuration, a user may hold the compression tool 242 such that the general plane of the tool is substantially orthogonal to the frame of the body surface tensioning device 240 in a "top-mount" manner. The user engages the block 252 with the opposite side section 244 so that the tool grips the stretching device tightly on its outer edge and squeezes inwardly with one hand on the finger grips 258, thus compressing the frame. Finger grip 258 and the area over which it extends may be sized and shaped to accommodate various hand sizes and reduce the force exerted on the user's hand during operation. When the tool is utilized in this manner, the user may sometimes find that removal of the compression tool from the frame is impeded by the frame of the stretcher having conformed to the shape of the body surface.

In an alternative configuration of the stretcher illustrated in fig. 11C, a recess in the substantially planar frame may enable a user to more easily remove the compression tool from the stretching device. Fig. 11C illustrates a skin stretcher 253 having a recess 255 formed in the outer edge of the skin stretcher 253. These recesses 255 provide defined locations where a suitably adapted compression tool can grasp and compress the stretching device 253. The recess 255 provides a location from which the tool can be more easily manipulated to assist in the removal of the tool from the frame of the stretching device regardless of whether the frame changes shape for the shape of the surface of the abutment. The recess feature may enable a user to compress and relax the skin stretcher more easily with only one hand.

The tool illustrated in fig. 11D is not only adapted to grip the skin stretching device 261 via the recesses 259 disposed on the outer edge of the skin stretching device 261, but is also adapted for use with the generally plane of the compression tool 257 being substantially parallel to the frame of the body surface stretching device 261. The use of this "side-mounted" compression tool 257 in conjunction with a female tension device 261 may reduce the distortion that the tension device 261 may experience when a user is compressing the frame.

The compression tool illustrated in fig. 11D includes a compass-like clamp having two diverging legs 263 connected at a hinge 265. Similar to the tools previously described, the distance between the bifurcated legs, the size of the finger grips, and the area over which they extend can be configured to optimize the performance of the device based on the intended user. The free ends of the legs 263 terminate at distal ends in end portions 267 that may be shaped to correspond to the outer edge of one of the side sections 244. In the illustrated embodiment, the end portion includes a projecting section configured to correspond to a recess or notch located in the opposing side section 244 and a side section configured to be positioned adjacent to the opposing side section 244. In use of this particular configuration, the user holds the compression tool 257 so that the general plane of the tool 257 is substantially coplanar with the body surface or frame of the skin stretching device 261. The user engages the projecting section 269, for example, into a recess or notch on the opposite side section 244 and squeezes inwardly with one hand on the finger grip, thus compressing the frame. When the body surface stretching device 267 has been placed on the body surface and the skin grasper (e.g., barb) has engaged the body surface, the user releases his grip on the compression tool 257, the frame of the stretching device 261 returns to its relaxed configuration, and the protruding section 269 is removed from the recess of the frame.

As was earlier suggested, the manner of using the compression tool may also promote a reduction in the distortion of the frame of the stretching device. Since the bifurcated legs of the two compression tools illustrated are hinged, it will be apparent that the ends of the legs move radially about the hinge. When utilized in the manner of a top-mounted compression tool, radial movement may be transmitted to the frame and cause planar distortion, e.g., in the form of frame distortion, when the frame is compressed and/or released in use. By using the compression tool in a side-mounted manner, the radial movement of the ends of the legs has less influence on the frame of the stretching device, especially if recesses are formed in the frame. An added advantage is improved visual access to the treatment area by the user.

Fig. 12A and 12B are top and bottom perspective views, respectively, of yet another alternative skin stretcher 260, the skin stretcher 260 having a closed-loop frame 262 and four contact members 264 each incorporating barbs 266. The frame 262 has a generally square configuration with four equal quadrants. Of course, as explained above, the principles embodied in this version may be transformed into other shapes and even into a frame that is open as opposed to a closed shape.

The frame 262 includes four side segments 270 a-270 d coupled to one another across a corner gap 272. The adjacent side segments 270 translate toward and away from each other via the shaft 274, and are biased away from each other by the spring 276. Much as with the butterfly frame described above, the four side segments 270 a-270 d may be compressed inwardly toward one another along the shaft 274 against the bias of the springs 276. The thumb lug 278 protrudes upwardly from the side segments 270 a-270 d and assists in manipulating the side segments 270 a-270 d.

Each side segment 270 a-270 d includes an inwardly directed contact member 264 connected thereto via a flexible joint 282 (e.g., a living hinge). The flexible joint 282 allows some rotation and movement of the contact member or pad 264 out of the plane of the side section 270 to accommodate skin surface curvature, for example, when working on a patient's head. The contact member 264 is capable of flexing in a vertical direction relative to and generally perpendicular to a plane defined by the side segments 270 a-270 d. An array of barbs 266 project downwardly from the skin contacting surface 284 on the bottom of each pad 264. In the illustrated embodiment, each contact member 264 comprises a rounded trapezoidal pad that widens toward the center of the frame 262. As seen in fig. 11B, the barbs 266 angle outward from the center of the frame 262 to achieve greater grip on the skin when pulled outward.

In use, a technician or any user compresses the frame 262 such that the side segments 270 a-270 d move toward each other against the spring 276 to narrow the gap 272. The user then presses the skin stretcher 260 against the patient so that the frame 262 encircles the treatment site and the barbs 266 engage the skin surface. The flexible nature of the contact members 264 helps the polymer of the pad conform to a circular surface, such as the scalp. Upon release of the frame 262, the side segments 270 a-270 d tend to move away from each other, thus causing the contact members 264 and barbs 266 to apply tension to the skin surface in the treatment area in four outward directions.

Fig. 13 illustrates yet another embodiment of a "butterfly" body surface stretching device or stretcher 290 in a relaxed configuration, shown as a top perspective view. The frame 292 is flexible and configured such that it can be compressed inwardly from a relaxed position. As an example, the frame 292 includes four contact members 294 a-294 d, the top surfaces of which are illustrated in fig. 13. Any or each contact member 294 a-294 d may feature a plurality of optional perforations 296 for receiving a skin grasper, such as a barb or a microbarb (not shown) as described above. Although illustrated as extending from the top surface to the bottom surface of the contact members 294 a-294 d, the perforations may take other forms, such as recesses in the bottom side or bottom surface of the contact members that do not extend all the way to the top surface of the contact members. Alternatively, the perforations 296 may not be present, and the skin grasper may be, for example, located or formed on or otherwise connected to the bottom side (or bottom) surface 306 of the contact member. The barbs extend beyond (extend below) the underside or bottom surface 306 of the contact member and provide an anchor on the body surface. This particular configuration shows the top surfaces of the contact members 294 a-294 d being angled or inclined relative to the body surface with which the contact members will make contact. The sloped top surface is illustrated as one continuous surface that tapers down toward the center of the opening 302, although alternative configurations and other geometries to achieve the slope may be used, for example, one or more steps or chamfers. Such an angled top surface may be useful when the stretcher is to be used in conjunction with a treatment tool (e.g., a hair harvesting tool), enabling the tool to be angled more easily relative to the treatment area defined by the opening 302 formed by the inwardly facing edges of the contact members 294 a-294 d. The angled top surface may be particularly useful when the stretching device 290 is to be used in conjunction with a robot or automated tool. In addition, the angled configuration of the top surface of the contact component also provides a more open or wider angle view that would be observed by any imaging device available when utilizing an automated or robotic system.

Although the contact members 294 a-294 d in this embodiment are in a general plane, the four flexible corners 298 that engage the four side sections may be angled (e.g., downward) relative to this general plane. The curvature of the frame formed by the angled flexible corners 298 is such that, when in use, the frame 292 rests closer to the body surface in question. The curvature may be symmetrical or asymmetrical across the frame 292, and may be appropriately shaped to fit the body surface in question.

The frame 292 may also include one or more channels or grooves 300 for receiving strands (not shown) therein. The strands may be relatively flexible, inflexible, relatively elastic, or inelastic, depending on the purpose for which they are to be used. Similar to the strands 32 discussed with reference to fig. 2, possible uses for the strands may include, for example, maintaining engagement of the contact member 294a or 294b to the body surface and/or creating additional tension across the body surface. In the case where the tensioning device 290 is being used to harvest hair from a donor area on the skin, the strands may be used to alter the angle of hair follicles that protrude from the body surface within the openings 302 formed by the edges of the contact members 294 a-294 d when the frame 292 is placed on the body surface. The frame may also have one or more additional grooves 304 in one or more of the contact members for receiving strands (also not shown). These strands may be used, for example, to secure the frame 292 in place during treatment.

As illustrated in fig. 13, a bottom surface of the contact member configured to contact the body surface, such as surface 306, is substantially planar. However, as illustrated in yet another embodiment of the stretcher 310 of fig. 14A and 14B, the bottom surface 306 of any one or more of the contact members 312 a-312 d may be curved or formed such that, when in use, the frame better conforms to the body surface in question. The curvature may be symmetrical or asymmetrical across the bottom surface of the contact members 312 a-312 d, and may be appropriately shaped to fit the body surface in question. In one particular configuration, such as when used to assist in hair harvesting from a donor area on the scalp, one or more of the bottom surfaces of the contact members 312 a-312 d may include a spherical radius that approximates the shape of the scalp. However, the center of the spherical radius of the bottom surface of one contact member does not necessarily match the center of the spherical radius of the bottom surface of another adjacent contact member. For example, in the illustrated embodiment of fig. 14A and 14B, the bottom surfaces of the two sets of opposing contact members may have their respective spherical radius offsets such that one set of opposing contact members contacts the surface (in this case the scalp) before the other set of opposing contact members.

In the example of a stretching device being used to assist a user in harvesting hair from a donor area, the user compresses the frame by pressing the two sides of the stretching device 290 together with a tool as described above. So doing, the user then pushes the contact members 294 a-294 d onto the body surface so that the barb/skin grasper engages the body surface. However, the user may find that while he/she is able to provide sufficient force via the contact members associated with the compression tool (e.g., 294c and 294d in fig. 13) to keep the barbs engaged in the body surface, the other contact members 294a and 294b that are not held by the compression tool may lift off or otherwise will not firmly contact the body surface. The user may have to use one hand to push the contact members 294a and 294b towards the body surface and the other hand to hold and operate the stretching device 290.

Fig. 14B is a bottom view of the stretcher 310 of fig. 14A illustrating the bottom surfaces of the contact members 312a to 312 d. Unlike the previous embodiment illustrated in fig. 13, the visible bottom surfaces of the contact members 312a and 312b are positioned in a substantially plane (which may be a curved substantially plane as explained above) that is different from the visible bottom surfaces of the contact members 312c and 312 d. In other words, if these bottom surfaces were placed on a treatment area of the body, one of the opposing sets of these bottom surfaces (e.g., the bottom surfaces of contact members 312a and 312 b) would first contact the treatment area before the other set. There are various ways in which this configuration can be achieved, one of which is described herein. Fig. 14A and 14B illustrate a configuration in which the top surfaces of all contact members 312 a-312 d are in a first general plane. The bottom surfaces of the contact members 312a and 312b are in a second general plane, and the bottom surfaces of the contact members 312c and 312d are in a third general plane. In use, this particular configuration assists the user in operating the stretcher more easily with only one hand. With the embodiment illustrated in fig. 14A and 14B, the user will find that the contact members 312a and 312B will engage the surface of the body before the contact members 312c and 312 d. In this particular embodiment, the above configuration is achieved by forming two contact members 312a and 312b to have different heights relative to the other two contact members 312c and 312 d. As illustrated in the embodiment shown, the depth 314 of the contact features 312a and 312b is greater than the depth of the contact features 312c and 312d from a first plane in which the top surfaces of all of the contact features 312 a-312 d are located as a reference. In the example of a stretching device being used to assist a user in harvesting hair from a donor area, the user will compress the frame by squeezing the two sides of the stretching device 310 together in the direction indicated by the inward arrow 320 with a tool as described above. With the embodiment illustrated in fig. 14A and 14B, the user will find that the contact members 312a and 312B will engage the surface of the body before the other contact members 312c and 312 d. By doing so, the barbs received therein will grip the body surface and be less urged to lift off the body surface as the user continues to push the remaining two contact members 312c and 312d to engage in the body surface. As indicated earlier, it will be apparent that differences in the disposition of the bottom planes (including the curved planes) associated with the respective contact members may be facilitated in other ways not described herein but within the scope of the invention described herein.

In order for the butterfly frame type device to sufficiently maintain engagement during the stretching process and during the duration of the treatment procedure, the described barbs are typically angled relative to the body surface rather than orthogonal to the body surface. In this orientation, the barbs encounter resistance from the body surface and are more easily retained therein. Fig. 15A shows a side view of the frame of the generally planar stretching device 330. FIG. 15A shows the device 330 in a relaxed or uncompressed configuration, and FIG. 15B shows the device 330 in a compressed configuration. The frame includes a contact member 332 that is curved in the particular illustration, the contact member 332 having a skin grasper 334 extending therefrom. In use, in order to move the frame configuration from the relaxed configuration of 15A to the compressed configuration of fig. 15B, a user must apply a compressive force to the frame. If the user were to use a tool similar to that illustrated in fig. 11A or 11B, a compressive force would typically be applied at the point 336 indicated in fig. 15B by grasping the stretching device from above. Application of the compressive force causes the frame to be compressed substantially in the plane of the frame and in a manner such that the barbs will remain at substantially the same angle as in the relaxed or uncompressed configuration. As illustrated, the point 336 at which the compressive force is applied is relatively high on the frame itself. Thus, when compressed in this manner, the compression is generally in the same plane as the frame of the stretcher itself. Thus, the movement of the barb is generally translational rather than rotational. That is, the orientation of the barbs relative to the body surface is substantially maintained. The desired angle of the barbs relative to the body surface is optimized to generally provide sufficient retention within the body surface within the time period required to complete a procedure or a step in the procedure. However, the same barb angle designed to provide sufficient retention can cause difficulties experienced by the user when initially engaging the barb into the body surface. Because of this, and because of the relatively small size of the butterfly frame, the user may also experience difficulty pressing the barbs downward and into the body surface of the patient while compressing and positioning the frame over the treatment area.

Fig. 16A and 16B illustrate an alternative embodiment that provides improved engagement of the stretcher with the body surface. Fig. 16A is similar to the embodiment of fig. 15A. The skin grasper (e.g., barb 334) is shown at a first angle θ relative to the body surface BS_FAs in fig. 15A, however, the figure shows the application of a compressive force at a lower point 338 relative to the plane of the frame of the stretching device 330. This compressive force may be applied using a compression tool such as the compression tools illustrated in fig. 11C and 11D. A tool of this nature facilitates gripping of the stretcher 330 not only from the side but also at a lower point. A compression tool such as that illustrated in fig. 11A and 11B (a tool used in a vertical position) may also be utilized, so long as it is adapted to apply a compressive force at a desired location. When compressed in this manner, in the illustrated configuration, the section 340 of the frame is lifted and the skin contacting member 332 is urged in a downward direction, as illustrated. Movement of the respective members 332 and 340 causes the orientation of the barbs 334 relative to the stretcher to change different than the first angle θ_FAngle theta of_SAnd in this example becomes more orthogonal to the body surface BS. The change in orientation of the barbs 334 assists the user in engaging the barbs with the body surface. In an orientation generally orthogonal to the body surface, the barbs encounter less resistance from the body surface and penetrate the body surface more easily. Once engaged, the user looses his grip and the compressive force is released. Movement of the respective contact members or sections 332 and 340 causes the orientation of the barbs 334 to again change relative to the body surface stretching deviceBack to the first angle theta_FThereby becoming less orthogonal to the body surface BS and encountering more resistance in order to retain the barbs in the body surface. According to the above embodiments, a method of applying tension to a body surface may comprise moving a frame of a tensioning device from a compressed configuration to a relaxed configuration so as to cause at least one skin grasper, e.g. a barb, positioned on the frame to move from a first angle relative to the body surface to a second angle relative to the body surface. In certain embodiments, the method comprises compressing a frame of the stretching device (the frame including a skin contacting member having a plurality of skin graspers) into a compressed configuration such that at least one of the plurality of skin graspers is disposed at a first angle relative to the body surface; and releasing the frame to cause the at least one of the plurality of skin graspers to move from the first angle relative to the body surface to a second angle different from the first angle, thereby creating tension across the body surface in a treatment area between the plurality of skin graspers. The method may further comprise removing hair grafts from the area of the body surface under tension or implanting hair grafts into the area of the body surface under tension.

Fig. 17 illustrates yet another alternative stretching device 342 and corresponding method of applying stretch, which exhibits the properties described with respect to fig. 16A and 16B. The illustrated example shows a flexible frame 342 including four contact members 346, each of the contact members 346 featuring a plurality of optional perforations 348 for receiving barbs or micro-barbs (not shown) as described above. In a relaxed configuration corresponding to the relaxed configuration illustrated in fig. 15A, the top surface of the contact member 346 is angled in a downward manner with respect to the body surface toward the center of the frame 342. The perforation 348 is also angled if present, or the skin grasper is angled if no perforation is present.

In a skin stretching procedure, the user compresses the frame 342 into the configuration shown in fig. 17 by squeezing the two opposing side sections with the recesses 344. As mentioned in the previous embodiment, the other two sides are also bowed inwardly. As the side moves inward, a more central portion of the skin contacting member (or contacting member) 346 is caused to rise due to the flexibility of the frame, and the more outwardly disposed portions of the contacting member 346 remain substantially at the same level. Due to the above compression, the initially angled skin grasper is caused to reorient substantially orthogonal to the body surface and thus can be engaged more easily in the body surface. The contact members 346 are then pressed onto the body surface surrounding the treatment area so that the redirected barbs (or similar skin grasper expedient) engage the skin or body surface. After releasing the frame 342, the contact members 346 return to their relaxed configuration and the barbs assume their original angled configuration, which in turn enables improved retention of the stretcher with the body surface.

It will be appreciated that the change in orientation may be facilitated by means other than that described above with reference to the examples of fig. 15-17. For example, the compression tool may be configured in a manner to apply a compressive force to the stretching device to enable a change in the orientation of the barbs to occur, or the shape of the stretching device may be configured to ensure that a compressive force is applied in a desired location, or the materials may be selected such that the frame compresses in a desired manner, or the overall design of the stretching device and/or compression tool may be such that all of the elements involved contribute to the end result, and/or any other means may be considered to contribute to the change in the orientation of the barbs.

It is to be understood that the words which have been used are words of description rather than limitation, and that various changes and modifications may be made to the invention described herein by those skilled in the art without departing from the scope of the invention. Furthermore, although individual features of one embodiment may be discussed herein or shown in the drawings of one embodiment and not in other embodiments, it should be apparent that individual features of one embodiment may be combined with one or more features of another embodiment or features from multiple embodiments. Accordingly, changes may be made within the appended claims without departing from the true scope of the application.

Claims (22)

1. An apparatus for applying tension to a body surface, comprising:

a flexible frame comprising at least three skin contacting members and at least one skin grasper;

the flexible frame is configured to move between a compressed configuration and a relaxed configuration such that compression of two of the at least three skin contacting members causes the at least three skin contacting members to converge, wherein in the relaxed configuration the flexible frame is biased and in the relaxed configuration the flexible frame is configured to provide tension in the body surface when the at least one skin grasper is engaged in the body surface.

2. An apparatus for applying tension to a body surface, comprising:

a flexible frame having a butterfly shape comprising two generally parallel side sections perpendicular to another two generally parallel side sections, the side sections connected by flexible corners, wherein the flexible corners extend generally diagonally outward from a center of an opening defined by the side sections, the flexible frame comprising a frame having at least one skin grasper;

the flexible frame is configured to move between a compressed configuration and a relaxed configuration, wherein in the relaxed configuration the flexible frame is biased and in the relaxed configuration the flexible frame is configured to provide tension in the body surface when the at least one skin grasper is engaged in the body surface; and wherein in the compressed state the size of the opening is reduced.

3. The device of claim 1 or 2, wherein at least a portion of the flexible frame comprises an elastic material.

4. The device of claim 1, wherein the flexible frame comprises portions shaped to make the flexible frame flexible and/or having a thickness that makes the flexible frame flexible.

5. The device of claim 1, wherein the at least three skin contacting members are connected by flexible corners.

6. The device of any one of claims 1 or 2, wherein the flexible frame comprises a plurality of skin contacting sections flexibly interconnected to one another.

7. The device of claim 1, wherein the flexible frame comprises a closed loop configuration defining a central opening therein.

8. The device of any one of claims 1 or 2, wherein the flexible frame provides substantially uniform tension across the body surface when positioned on the body surface in the relaxed configuration.

9. The device of any of claims 1 or 2, wherein the flexible frame is configured to conform to the body surface.

10. The device of claim 1 or 2, wherein the flexible frame comprises one or more fiducial points visible under image guidance.

11. The device of any one of claims 1 or 2, wherein the skin grasper comprises one or more of a barb, a micro barb, an adhesive, or a rough surface texture.

12. The device of any of claims 1 or 2, wherein the skin grasper comprises at least a first barb and a second barb, the first barb being angled away from the second barb.

13. The device of any of claims 1 or 2, wherein the skin grasper is a barb or a micro-barb, and when positioned on the body surface, in the compressed configuration the barb is directed at a first angle relative to the body surface, and in the relaxed configuration the barb is directed at a second angle relative to the body surface.

14. The device of claim 13, wherein the first angle is substantially orthogonal to the body surface and the second angle is an angle different from substantially orthogonal to the body surface.

15. The device of claim 1 or 2, wherein the frame is molded.

16. The device of claim 1, wherein a first one of the at least three skin contacting members is in a first plane and a second one of the at least three skin contacting members is in a different plane than the first plane.

17. The device of claim 5, wherein the frame has a butterfly shape with two substantially parallel side sections perpendicular to the other two substantially parallel side sections, and the flexible corners extend substantially diagonally outward from a center of an opening defined by the side sections.

18. The device of any of claims 1 or 2, wherein the flexible frame is generally planar in the relaxed configuration and the frame is configured such that a portion of the frame flexes out of the plane when the flexible frame is compressed.

19. The device of any of claims 1 or 2, further comprising an input port for delivering fluid to the body surface and an output port for removing fluid from the body surface.

20. The device of any one of claims 1 or 2, wherein at least one of the skin contacting members comprises a chamber such that when positioned on the body surface, a vacuum can be created within the chamber to create suction between the contacting member and the body surface.

21. The device of any one of claims 1 or 2, wherein the device is configured and sized to stretch the body surface containing hair follicles to facilitate harvesting hair follicles from the stretched body surface.

22. The device of any of claims 1 or 2, further comprising: an indicator on the flexible frame that displays a magnitude of the stretch being applied to the body surface; and/or a stretch control on the flexible frame that enables adjustment of the amount of the stretch being applied to the body surface.