APPARATUS FOR THE CLOSURE OF WIDE SKIN DEFECTS BY STRETCHING OF SKIN

Abstract: An apparatus for closing wide skin defects comprises two long pins (I, I') for insertion underneath the skin close to the margins of the defect; two U-shaped members (II, II') each provided with a sharp hook (23) at the end of each leg (20) adapted to pierce the skin and to engage one pin (I, I') each in two places; and a contracting screw (IV) connecting the two members (II, II') and adapted to approximate the pins (I, I') and the skin margins until final closure of the defect.

Description: APPARATUS FORTHECLOSURE OFWIDE SKIN DEFECTS BYSTRETCHING OFSKIN BACKGROUNDOFTHEINVENTION The invention relates to apparatus serving to stretch skin so as to cover an open wound and to enable the surgeon to suture together the opposite skin margins. It relates especially to apparatus to be used during operations following wide excision of skin lesions or for closure of skin defects or otherwise damaged skin areas, thereby obviating the conventional method of using local skin flaps or grafting of skin from other body portions. U.S. Patent No.4,896,680, by one of the present inventors, Bernard Hirshowitz, describes a method and apparatus for stretching the skin over a wound by load cycling including applying a pulling force on opposite skin margins during several periods interrupted by relaxation periods. In this way the skin can be stretched over a wide area in a manner not previously used until the invention by Bernard Hirshowitz. The above patent discloses a surgical stretching apparatus which comprises two pins to be inserted into the skin along both edges of the wound which are gradually pulled together by means of a flexible strap. According to the invention the pulling is done in intervals to allow the collagen fibers of the skin to rearrange themselves for further stretching. The pins of the described apparatus are more or less in the shape of safety pins each provided with a loop for attachment to the flexible strap; the strap, for its part, has projections or apertures for engagement with a ratchet-shaped device which will hold the two pins in forceful apposition. It has, however, been shown that the described apparatus has certain drawbacks which should be overcome by the present invention, the main drawback being that after the two pins have been drawn together, SUBSTITUTE SHEET they do not leave room for suturing the approximated skin margins. Another drawback is that manual pulling on the flexible strap is rather crude, in that the pulling force cannot be minutely controlled. And finally that the two pins grip only relatively narrow strips of skin along both edges, thereby not permitting closure of a wide wound by one pulling operation. It is, therefore, an object of the invention to provide apparatus which will permit suturing together of the skin edges while the stretching apparatus is in situ without disturbing the suturing operation. It is another object to permit insertion into the skin edges of longer pins adapted to grip practically the entire length of the wound and to permit shifting of the stretching means along the wound edges thereby enabling the two pins to be engaged in different locations. And it is a further object to permit prolonged use of the apparatus as well as of the pins, contrariwise to the apparatus described in the previous patent which had to be disposed after one use. SUMMARY OF THE INVENTION A preferred embodiment of the apparatus for stretching skin comprises essentially; 1. two long pins to be inserted under the skin along the two edges of a wound to be closed; 2. two U-shaped retaining members each having a top surface, and a bottom surface to be placed close to the skin, each member being provided with a sharp hook at the end of each leg of the "U"; 3. Contracting means for pulling and approximating the two retaining members with their legs extending towards the open wound. The retaining members are adapted to be placed behind the pins in opposite alignment with their hooks piercing the skin SUBSTITUTE SHEET and engaging the respective pin in a position along the wound edges. The contracting means are designed to pull the two retaining members slowly and gradually together so as not to cause damage to the skin area. The U-shape permits suturing of the skin edges with the apparatus in position, due to the open spaces left between and on both sides of the two legs. A preferred embodiment of the contracting means comprises two contractor arms in parallel alignment, connected by a screw means adapted to approximate the two components by rotating the screw means. One end of each contractor arm is in the shape of a bar of smooth, even cross section adapted to retain one retaining member each in opposite alignment on both sides of a wound and to allow shifting of each retaining member along its respective bar. The contractor arms are preferably slidably connected at their other ends by a smooth bar engaging with bores in corresponding locations with a view to keeping the two arms in parallel alignment. Each U-shaped retaining member comprises two legs with outwardly bent hooks at the bottom surface of their ends connected by a longitudinally perforated flange adapted to be singly mounted on the smooth bar of a contractor arm. After the two pins have been inserted along the wound margins, the apparatus is placed across the wound with the retaining members positioned behind the skin margins, while the hooks are pressed through the skin into engagement with the pins. Now the screw means is rotated so as to slowly approximate the two contractor arms and the attached retaining members and the operation is continued at intervals as described in the aforementioned patent. Another embodiment of the apparatus comprises two U-shaped retaining members having forwardly bent hooks attached to the underside of the legs at their respective ends, a connecting flange provided with a SUBSTITUTE SHEET lug protruding out of its top surface which is perforated and provided with screw thread for engagement with a screw adapted to be rotated for the purpose of approximating the two members. A preferred embodiment of the apparatus includes one screw-threaded member and one smooth-bored member, and a screw provided with a collar at its one end engaging with the smooth bore and screw thread over its remaining length engaging with the screw-threaded member. The drawback of this apparatus, compared with the afore-described one, lies in the obstruction caused by the screw preventing suturing of the area between the two legs. Other contracting means may be provided for approximating the two retaining members, but it will be understood that the essence of the invention lies in the shape of the two retaining members which permits suturing of the wound margins while the apparatus is still in situ, pulling the margins together. BRIEF DESCRIPTION OF THE DRAWINGS. Figure 1 is a plan view of an apparatus positioned over an open skin wound, Figure 2 is a section through the apparatus along line A-A of Figure 1, Figure 3 is a section through the apparatus along line B-B of Figure 1, Figure 4 is a side view of the apparatus along line C-C of Figure 1, Figure 5 is a top view of another embodiment of the apparatus of the invention, and Figure 6 is a side view of the apparatus illustrated in Figure 5. DETATT.ED DESCRIPTION OF THE DRAWINGS With reference to Figures 1 through 4 of the drawings the skin stretching apparatus comprises two long pins I and F each provided with SUBSTITUTE SHEET a head 1 which are inserted under the skin along the wound margins as shown in Figures 1 and 2, and two retaining members II and IF each engaging one of the two pins. Each retaining member is in U-shape and comprises two parallel, spaced-apart legs 20 connected by a flange 21 which is longitudinally perforated by a bore of rectangular cross section (22). Forwardly extending hooks 23 are connected to the underside of the members one each at the end of each leg 20 which are shown to have pierced the skin and to have engaged the pins from the side remote from the wound. The retaining members are held in position by two contractor arms III and III' and are slidingly mounted on the bar-shaped ends 30 by means of their rectangular bores 22. The contractor arms are held in parallel alignment by a cylindrical bar 31 which extends through horizontal bores in lugs 32 at the other ends of the arms. A screw IV is adapted to pull the two arms together and extends through a screw- threaded bore in a lug 33 on the top surface of the arms III and through a smooth bore in a lug 33' on the top surface of the arm III'. The screw IV comprises a screw-threaded end 40, a collar 41 abutting to the lug 33' of arm III' and a handle or knob 42 attached to the screw IV by means of a flexible tube or helical spring 43. By rotating the handle 42 the screw- threaded end in engagement with the thread in the lug 33 pulls the arms III and III' to each other whereby the retaining members II and IF contract the wound margins by means of the hooks 23 and the pins I and I'. AS described in the previous patent, the operation is performed in several stages to allow the skin to stretch in a gradual manner during intervals between the stretching stages. After the wound margins have been contacted the wound is sutured in a manner known to the art, whereby it is evident that the legs 20 do not interfere with the operation, being remote from the margins. A second embodiment of the apparatus is illustrated in Figures 5 and 6, wherein two retaining members 5 and 5' are contracted by a screw SUBSTITUTE SHEET 6. The members which are essentially identical with those shown in Figures 1 and 2, are provided with perforated lugs 51 and 51' on their respective top surfaces, lug 51 being perforated by a screw- threaded bore and lug 51' by a smooth bore. The screw 6 comprises a screw-threaded end 61 cooperating with the screw thread in lug 51 of member 5, a smooth portion 62 rotating in lug 51', a collar 63 abutting lug 51' and a flexible operating portion 64 terminating in a knob or handle 65. The skin contracting operation is similar to that described with reference to the former embodiment, however it becomes evident that the screw 6 somewhat obstructs the suturing operation. SUBSTITUTE SHEET

Claims: WE CLAIM 1. An apparatus for the closing of wide skin defects by gradual stretching of skin comprises, two long pins serving for insertion underneath the skin close to the margins of the skin defect to be closed, two U-shaped retaining members each having a top surface, and a bottom surface to be positioned close to the skin, each member being provided with a sharp hook at the end of each leg of said "U" protruding out of its bottom surface, said hooks serving for insertion into the skin behind each said pin and to engage said pin, with said hooks on said two members positioned in opposite alignment, contracting means connecting said two retaining members and adapted to approximate said retaining members and said pins by screw means, until final closure of said skin defect. 2. The apparatus as defined in Claim 1, wherein said contracting means comprise two contractor arms in parallel alignment, each said arm carrying one said retaining member in sliding engagement, said contractor arms being connected by screw means for mutual approximation by manual rotation of said screw means. 3. The apparatus as defined in Claim 2, wherein each said contractor arm includes a straight and smooth bar at its one end, and wherein each said retaining member comprises two legs connected by a flange remote from said skin margin, said flange being longitudinally perforated by a bore cooperating with said bar of said contractor arm and mounted on said bar in sliding engagement. 4. The apparatus as defined in Claim 3, wherein each of said contractor bar is provided with a bore perpendicular to said straight bar, and wherein a screw extends through said bores in said two arms connecting said two arms, and wherein one of said arms is provided with a smooth bore and the other with a screw-threaded bore cooperating with the screw thread of said screw. SUBSTITUTE SHEET 5. The apparatus as defined in Claim 4, wherein said screw connecting said two contractor arms includes a screw-threaded portion engaging said screw-threaded bore, with a collar abutting the smooth bore • on the side remote from said skin defect and with a handle or know for manual rotating said screw. 6. The apparatus as defined in Claim 4, wherein said two contractor arms are provided with coaxial bores at the ends remote from said straight bars and are connected by a cylindrical bar extending through said two bores in sliding engagement. 7. The apparatus as defined in Claim 6, wherein each said contractor arm has a bottom surface to be positioned close to the skin and a top surface remote from the skin and wherein said bores are provided in lugs protruding out of the top surface of said arms. 8. The apparatus as defined in Claim 1, wherein each of said two U-shaped retaining members comprises two parallel legs connected by a flange, said flange being perforated by a bore in parallel alignment with said legs and wherein said retaining members are connected by a screw means extending through said bores and are adapted to be approximated by rotation of said screw in screw-thread provided in at least one of said bores. 9. The skin closing apparatus according to claim 8, wherein one of said U-shaped retaining member bores is a threaded bore, another of said U-shaped retaining member bores is a smooth bore, said contracting mechanism comprising at least a screw extending through said U-shaped retaining member bores. 10. The skin closing apparatus according to claim 1, wherein said plurality of U-shaped retaining members comprises two U-shaped retaining members, each of said retaining members exhibits two legs, a flange connecting said legs and a bore. 11. The skin closing apparatus according to claim 1, wherein said plurality of pins comprises two pins. 12. A skin defect closing apparatus comprising: a plurality of retaining members, each of said retaining members exhibiting: at least two legs, a flange connecting said legs and exhibiting a bore located between said legs, a plurality of skin piercing elements, each of said skin piercing elements protruding from a surface of one of said legs; and a contracting mechanism connecting said retaining members and engaging one of said flange bores, said contracting mechanism configured to approximate said retaining members. 13. The skin defect closing apparatus according to claim 12, wherein each of said retaining members is configured so said retaining member legs are in parallel alignment. 14. The skin defect closing apparatus according to claim 12, further comprising two pins, each of said pins is configured for insertion underneath skin proximal to a margin of a skin defect, each of said retaining member skin piercing elements engaging one of said pins. 15. The skin defect closing apparatus according to claim 12, wherein said plurality of retaining members comprises two retaining members. 16. The skin defect closing apparatus according to claim 12, wherein each of said skin piercing elements is a skin-piercing hook, said plurality of skin-piercing hooks comprising two skin-piercing hooks. 17. A skin defect closing apparatus according to claim 12, wherein said contracting mechanism comprises at least a screw. 18. A skin defect closing apparatus according to claim 17, wherein one of said retaining member flange bores is a screw-threaded bore, said screw engaging said screw-threaded bore. 19. A skin defect closing apparatus according to claim 17, wherein one of said retaining member flange bores is a smooth bore, said screw exhibits a collar configured to contact said retaining member exhibiting said smooth bore, said screw extending through said smooth bore. 20. A skin defect closing apparatus according to claim 17, further comprising a knob and a flexible portion attached to said screw and said knob, said screw is adapted to be rotated by said knob. 1

Inventors: HIRSHOWITZ BERNARD, LEVY AMNON, HIRSHOWITZ, BERNARD, LEVY, AMNON
Applicants: LIFE MEDICAL SCIENCES INC, LIFE MEDICAL SCIENCES, INC.
Application year: 1992
Main classification: A61B17
IPC codes: A61B17