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Publication numberUS3665927 A
Publication typeGrant
Publication dateMay 30, 1972
Filing dateMay 29, 1968
Priority dateMay 29, 1968
Also published asDE1936965A1, DE1936965B2, DE1936965C3
Publication numberUS 3665927 A, US 3665927A, US-A-3665927, US3665927 A, US3665927A
InventorsKurtz Leonard D
Original AssigneeSutures Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Impregnation of polyfilamentous sutures with synthetic polymer particles
US 3665927 A
Abstract
Polyfilamentous sutures having the attributes of a monofilamentous suture are prepared by impregnating the sutures with an aqueous dispersion of inert, synthetic polymeric particles and then subjecting the impregnated suture to centrifugal force to simultaneously extract water and dry the suture.
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Description  (OCR text may contain errors)

United States Patent urtz [54] IMPREGNATION OF POLYFILAMENTOUS SUTURES WITH SYNTHETIC POLYMER PARTICLES [21] Appl. No.: 732,859

[52] [1.5. CI. ..128/335.5,ll7/l01', 117/141,

117/161 R [51] Int. Cl. ..A6lI17/00 [58] Field ofSearch ..l17/l01, 141, 145, 161 R, 169; 128/3355 1 1 *May 36, 1972 [56] References Cited UNITED STATES PATENTS 2,888,363 5/1959 Matter et al. .1 17/102 x 3,322,125 5/1967 Kurtz ..128/335.5 2,193,188 3/1940 Bradley... 1 28/3355 2,478,229 8/ 1949 Be ..260/29.6 2,734,506 2/1956 Nichols et a]. 128/3355 2,890,136 6/1959 Vaughan et a1 ....117/143 3,379,552 4/1968 Kurtz ..117/7 3,424,164 1/1969 BlOCh et al ..128/335.5

Primary Examiner-Edward G. Whitby Attorney-Larson, Taylor & Hinds [57] ABSTRACT Polyfilamentous sutures having the attributes of a monofilamentous suture are prepared by impregnating the sutures with an aqueous dispersion of inert, synthetic polymeric particles and then subjecting the impregnated suture to centrifugal force to simultaneously extract water and dry the suture.

6 Claims, No Drawings IMPREGNATION OF POLYFILAMENTOUS SUTURES WITH STIC POLYMER PARTICLES This invention relates to surgical sutures. More particularly, the invention relates to sutures having decreased reactivity with tissue and to a method for their preparation.

Sutures are classified either as absorbable or nonabsorbable and may be polyfilamentous or monofilamentous. Polyfilament sutures are preferred by surgeons because they have superior knotting characteristics relative to monofilament materials; On the other hand, monofilament sutures are preferable for the patient as there is less trouble in cases of infection.

It is generally accepted that monofilaments, such as monofilament stainless steel, monofilament nylon, monofilament polyethylene and monofilament polypropylene are the most inert of the nonabsorbable sutures. When implanted in an area where infection occurs, as a rule, they are not spit" spontaneously by the wound, nor do they require surgical removal. On cross section, all of these monofilaments have one thing in common. They are solid with no dead spaces or interstices.

On the other hand, braided and twisted sutures when implanted where infection occurs, will, as a rule, be spit spontaneously by the wound, or require surgical removal in order for healing to occur. On cross section, the braided and twisted sutures consist of many filaments and dead spaces. For example, on cross section, braided silk has 40 to 50 percent dead space.

On the basis of the above facts, it seems possible that there is a direct relationship between dead spaces in a suture and the incidence of spontaneous spitting or the necessity for surgical removal of the suture when infection occurs. if this hypothesis is correct, monofilaments should be the sutures of choice for the patient undergoing surgery. However, surgeons have a great deal of difiiculty in their use. All of them are stiff, difficult to knot, and have a tendency to open spontaneously. Some, in addition, have sharp ends, kink, or are too elastic. All monofilaments apparently pose difficulties in surgical techniques. Many surgeons continue to use the monofilaments despite their problems because of the excellent patient response. However, obviously, monofilaments cannot be used if the surgical knotting technique becomes inadequate.

It is an object of the present invention to provide a method whereby polyfilament sutures can be imbued with monofilament characteristics.

These and other objects, which will become apparent in light of the description which includes a preferred embodiment, are achieved according to the invention by substantially eliminating the dead air spaces in a polyfilamentous suture by filling the interstices of the silk suture with a plurality of solid particles of synthetic polymeric materials. It has been discovered that the reactivity of the polyfilamentous suture can be reduced to such an extent that reactivity of the suture is as low as reactivity of a monofilament when these solid particles are incorporated therein.

The inert material used to fill the sutures may be any suitable inert, insoluble, synthetic polymeric material small enough to penetrate the interstices of the silk suture. Tetrafluroethylene polymers such as Teflon(polytetrafluoroethylene) are particularly suitable as particles. Other inert, insoluble synthetic resins which can be used include polyolefins such as polyethylene, polypropylene and the like; polydiolefins such as polymers of butadiene and isoprene; polystyrene; polyesters, polyamides and like materials. Aqueous dispersions of these materials such as the aqueous dispersions of Teflon described in Berry, US. Pat. No. 2,478,229 are suitable to incorporate the particles into the suture. Saturated aqueous dispersions are particularly suitable. Ordinarily, the inert particles employed will have a particle size of up to 1 micron.

The sutures which can be improved according to this invention include all nonabsorbable sutures. Illustrative of such sutures are polyfilament sutures made from silk; hydrophobic synthetic materials such as polyesters (e.g. Dacron), polyolefins (e.g. polypropylene), polyamides (e.g. nylon and polyacrylonitrile), and like materials;- cotton and linen.

It is believed that by filling the dead space within the interstices of the silk suture, the pockets which are conducive to harboring invading organisms are eliminated or at least reduced to an extent that clinical results indicate that the su ture is monofilamentous. In other words, while it is not certain that the voids are eliminated, the sutures produced in accordance with this invention behave like a monofilament. In any event, the amount of the particles introduced into the suture should be an amount sufiicient to render the suture substantially monofilamenteous. It is preferred, however, that the particles substantially fill the dead space within the interstices of the suture. The exact amount of particles necessary to fill the dead spaces within the suture varies with the nature and configuration of the suture and, of course, on the density of the particulate matter employed. For instance, a minimum of about 6 percent by weight of polytetrafluoroethylene based on the weight of the suture up to as much as may be impregnated into the suture and which will remain there is generally used to render the suture substantially monofilamentous. The maximum will depend upon techniques as well as materials and pressurized impregnations that may be used. it should be noted, however, that a suture exhibiting monofilamentous characteristics can be obtained without entirely filling the dead spaces in the suture.

Impregnation of the suture is accomplished in accordance with the present invention by immersing the suture in an aqueous dispersion of the solid polymeric particles for a time sufficient to introduce said polymeric particles into the suture. After the immersion, the impregnated suture is subjected to centrifugal force to extract the water carrier and simultaneously dry the suture. This extraction-drying step has been found to provide a suture having the polymeric particles distributed and set uniformly and homogeneously throughout the entire suture. Thus, the method of the invention prevents the dripping and exuding of the aqueous dispersions from the impregnated suture which causes nonuniform distribution and loss of impregnated particulate matter.

Any suitable centrifuge or spinning means capable of providing a centrifugal force sufficient to remove the water carrier and dry the suture while spinning can be used. It is preferred, however, that a relatively slow extractor be employed in order to avoid the throwing off of impregnated solid particles that is likely to occur with excessively fast extractors. Although fast extractors, for example, extractors having a spinning rate of 1600 to 1750 or more r.p.m., can be employed for the extraction-drying operation, they frequently necessitate repeated impregnation-spinning cycles to provide the desired final product. Use of slower extractors for the extraction-spinning operation such as an extractor having a spinning rate of about 700 r.p.m., for example, provides the desired impregnated suture in a single cycle. The spin time will vary, of course, with the centrifugal force to which the impregnated suture is subject. With the slower extractors, the spin time is usually at least 1 minute. If desired, heat may be provided the spinning means to reduce the spinning time.

Wax, of course, has been used for treating polyfilament silk sutures for years. Likewise, silicones have also been proposed to treat Dacron and silk polyfilament sutures for various reasons. In these and all analogous instances, however, the sutures when used clinically have behaved like polyfilaments and not like monofilaments. If is believed that the monofilament characteristics achieved by the present invention are due primarily to the use of dispersions of the solid particles to load the suture with the particulate matter. The old wax-type and silicone treatments have been strictly concerned with the use of liquid solutions of the was or silicon material.

The following examples are included to further illustrate the present invention.

EXAMPLE I A silk suture is immersed in a suspension of colloidal size Teflon (polytetrafluoroethylene) particles available from Dupont as Teflon Te 3170, and having an average particle size of about 0.2 micron. The suspension described by Berry, US. Pat. No. 2,478,229 is also suitable for this purpose. The suture has a core of 3 ends of 2 threads and a braided cover of 12 ends of 2 threads. The total denier of the suture is 420. The impregnation is continued for 5 minutes after which it is subjected to spinning and drying for minutes in a spin-extractor at a spinning rate of 700 r.p.m. The resulting suture exhibits a weight gain of about 9 percent and behaves substantially like a monofilament. The particles of Teflon remain tenaciously imbedded in the body of the suture and repeated wash cycles will not dislodge a detectable amount thereof.

The sutures can be sterilized in the usual manner and at any stage of manufacture or may be sterilized by the user. Since silk sutures tend to swell in water or steam, it is preferred to sterilize them by electromagnetic radiation techniques or with ethylene oxide. The sutures may, of course, be attached to surgical needles.

EXAMPLES lI-lll Polyfilamentous silk sutures exhibiting monofilament characteristics can be prepared by substituting the following synthetic particles in the process described in Example I: Example ll-polyethylene; Example III-polystyrene in latex EXAMPLE IV A 40 polyfilamentous suture made from Dupont type 55 Dacron and having a 4 thread core of 56 denier and a braided cover with two threads of 13-15 denier per carrier is provided with monofilamentous characteristics by impregnating the suture by the method described in Example 1 above.

It is claimed:

1. A method for imparting attributes of a monofilament to a polyfilament suture comprising the steps of immersing a polyfilamentary suture in an aqueous dispersion of insoluble, inert synthetic polymeric particles, the particles being of a size sufficiently small to enter within the interstices of the suture, maintaining the immersion to introduce said polymeric particles into said suture in an amount sufficient to imbue the polyfilament suture with substantially monofilamentous properties and subjecting said impregnated suture to centrifugal force to simultaneously extract water and dry said suture.

2. A method according to claim 1 wherein the suture is polyfilament silk and the synthetic polymeric particles are particles of tetrafluoroethylene polymer.

3. A method according to claim 2 wherein the tetrafluoroethylene particles are polytetrafluoroethylene particles having an average size of up to 1 micron.

4. A method according to claim 3 wherein the suture is filled with at least 6 percent by weight said particles based on the weight of the suture.

5. A suture comprising a polyfilamentary silk suture having a plurality of fine, solid particles of inert, insoluble, synthetic polymeric material incorporated in the interstices thereof in an amount sufiicient to imbue the polyfilament silk suture with substantially the properties of a monofilament.

6. The suture of claim 5 wherein the solid particles are of tetrafluoroethylene polymer.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2193188 *Jun 16, 1938Mar 12, 1940American Cyanamid CoNoncapillary silk suture and method of preparing the same
US2478229 *Sep 5, 1946Aug 9, 1949Du PontConcentrated aqueous colloidal dispersions of polytetrafluoroethylene and methods for their preparation
US2734506 *Dec 14, 1953Feb 14, 1956 Silk sutures and ligatures
US2888363 *Jul 8, 1955May 26, 1959American Viscose CorpMethod for applying finish to filamentary yarns
US2890136 *Jan 16, 1956Jun 9, 1959Canadian Hanson And Van WinkleSisal buff resin impregnation method
US3322125 *Apr 4, 1966May 30, 1967Sutures IncSutures and method of making same
US3379552 *Nov 15, 1963Apr 23, 1968Sutures IncImpregnation of stretched multifilament polyester suture with polytetrafluoroethylene
US3424164 *May 20, 1966Jan 28, 1969Ethicon IncSilk suture
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3755824 *Sep 24, 1971Sep 4, 1973Plus Hair Centers Int IncMethod for avoiding the appearance of baldness
US4362162 *Mar 23, 1981Dec 7, 1982Daikin Kogyo Co., Ltd.Surgical sutures
US4461298 *Jul 26, 1982Jul 24, 1984Ethicon, Inc.Composite sutures of silk and hydrophobic thermoplastic elastomers
US4649920 *Jan 30, 1986Mar 17, 1987Pfizer Hospital Products Group, Inc.Coated suture
US5051272 *Jul 19, 1988Sep 24, 1991United States Surgical CorporationMethod for improving the storage stability of a polymeric article susceptible to hydrolytic degradation and resulting article
US5165993 *Feb 19, 1991Nov 24, 1992Akzo N.V.Aromatic polyamide yarn impregnated with lubricating particles, a process for the manufacture of such a yarn, and packing material or rope containing this yarn
US5222978 *Aug 16, 1990Jun 29, 1993United States Surgical CorporationPackaged synthetic absorbable surgical elements
US5312642 *Mar 5, 1993May 17, 1994United States Surgical CorporationMethod and apparatus for calendering and coating/filling sutures
US5359831 *Jun 18, 1993Nov 1, 1994United States Surgical CorporationMolded suture retainer
US5366081 *Jul 10, 1992Nov 22, 1994United States Surgical CorporationPackaged synthetic absorbable surgical elements
US5447100 *Feb 14, 1994Sep 5, 1995United States Surgical CorporationApparatus for calendering sutures in orthogonal directions
US5468252 *Jun 22, 1993Nov 21, 1995United States Surgical CorporationPackaged synthetic absorbable surgical elements
US5503638 *Feb 10, 1994Apr 2, 1996Bio-Vascular, Inc.Soft tissue stapling buttress
US5540773 *May 18, 1995Jul 30, 1996United States Surgical CorporationApparatus for calendering and coating/filling sutures
US5769892 *Oct 22, 1996Jun 23, 1998Mitroflow International Inc.Surgical stapler sleeve for reinforcing staple lines
US8869584Apr 9, 2008Oct 28, 2014Panduit Corp.Progressive crimping method
US20050100733 *Aug 13, 2004May 12, 2005Foss Manufacturing Co., Inc.Synthetic fibers modified with PTFE to improve performance
US20060246096 *Dec 29, 2004Nov 2, 2006University of Debrecen, Department of Colloid and Environmental ChemistryNanoparticles from biopolymers
US20090255319 *Apr 9, 2008Oct 15, 2009Panduit CorpProgressive Crimping Method
Classifications
U.S. Classification606/231, 427/2.31, 427/352, 427/240, 428/372
International ClassificationA61L17/00, A61L17/14
Cooperative ClassificationA61L17/145
European ClassificationA61L17/14C
Legal Events
DateCodeEventDescription
Oct 17, 1985AS01Change of name
Owner name: HOWMEDICA, INC.
Effective date: 19840624
Owner name: PFIZER HOSPITAL PRODUCTS GROUP INC.
Oct 17, 1985ASAssignment
Owner name: PFIZER HOSPITAL PRODUCTS GROUP INC.
Free format text: CHANGE OF NAME;ASSIGNOR:HOWMEDICA, INC.;REEL/FRAME:004471/0589
Effective date: 19840624