1. Surgical clamping means comprising a pair of jaws mounted for movements toward and from each other, each of said jaws comprising at least one longitudinal rib having a row of teeth and at least one longitudinal groove located to receive the teeth of the rib of the opposite jaw, the teeth of the ribs on the respective jaws being laterally disposed relatively to each other, the ribs on the respective jaws having longitudinally extending flanks which are closely adjacent to each other when the jaws are in clamping relationship, and which are shaped to provide a longitudinally extending tissue-receiving pocket having, in transverse cross section an enlarged central portion and reduced end portions.
2. A clamp according to claim 1 in which each of said flanks is concave.
3. A clamp according to claim 1 in which the teeth are rounded.
4. A clamp according to claim 1 in which the jaws are provided with engageable surfaces to prevent engagement of the ribs with each other when the jaws are closed.
FIELD OF THE INVENTION
The invention relates to surgical clamping means adapted to clamp tubular vessels of the body or other tissues during surgery with avoidance of damage thereto.
DESCRIPTION OF THE PRIOR ART
Surgical forceps and other surgical clamping means have been made with a great variety of types of jaws having variously grooved, serrated, perforated or the like surfaces for the purpose of securing reliable holding despite slipperiness of vessels or other tissues which are clamped. Many of these have had the fault that when in use with sufficient application of force to prevent slippage they have damaged the clamped tissues either by penetrating or cutting them or by squeezing them too tightly with a crushing action.
Such damage has been avoided to a very major extent by the adoption of clamping means of the type disclosed in the Elvin E. Baker U.S. Pat. No. 2,668,538, dated Feb. 9, l954.
SUMMARY OF THE INVENTION
In accordance with the present invention, the type of clamping means disclosed in said Baker patent is still further improved by utilizing a somewhat different principle of operation. While in the Baker patent relatively sharp teeth are utilized to effect secure clamping, though they are so arranged that despite their sharpness they are prevented from penetrating or cutting the clamped tissues, the present invention makes possible secure clamping without the presentation to the tissues of sharp edges and thereby prevents even accidental damage to delicate tissues. Despite the existence of rounded edges, effective clamping is secured by utilization of the fact that the body tissues in general have elastic properties by virtue of which they resist deformation, particularly in the sense of resisting compression such as would be required to cause a tissue to pass from an enlarged region in which it was expanded into a more restricted region which would require its compression. The clamping means in accordance with the present invention provides, in effect, pockets which permit a tissue to expand, in association with restricted regions so that movement from the former into the latter would require substantial distortion by compression or other deformation of the tissue. In the case of tubular vessels, the compression action is further resisted by entrapment of liquid which would have to be extruded through clamped portions of a vessel to permit slipping movement. The characteristics giving rise to the effectiveness of the invention will become clearer from the following description.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plan view of a forceps provided in accordance with the invention;
FIG. 2 is an elevation of the same;
FIG. 3 is a fragmentary view showing gripping portions of the jaws of the forceps greatly enlarged and open;
FIG. 4 is a section taken on the plane the trace of which is indicated at 4--4 in FIG. 3, the jaws being completely closed; and
FIG. 5 is a view similar to FIG. 4 but showing the jaws clamping a vessel but not completely closed.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Clamps provided in accordance with the present invention may be of any conventional construction aside from the formation of the clamping surfaces of the jaws. FIGS. 1 and 2 show, for example, forceps comprising the members 2 and 4 which are hinged at 6 and provided with finger-receiving rings 12 and a latching arrangement indicated at 14 comprising interengaging toothed projections. The jaws 8 and 10 may have conventional shapes aside from the clamping surface structure and it will be understood that the invention is quite generally applicable to a great variety of forceps and other clamps having straight or curved jaws of various dimensions depending upon the particular uses for which they are intended. The handles or other manipulating means may be of various types including springs, wedges, cam devices, screws or the like for the purpose of closing or adjusting the jaws.
The jaws may be wholly or only partially serrated in accordance with the invention and the general nature of the serrations provided in carrying out the invention will be made clear from FIGS. 3 and 4 which show a preferred arrangement of the serrations for an aortic clamp.
The construction of the jaws may be made clear by describing the operations involved in the formation of their clamping surfaces. Referring first to the jaw 8, and assuming that milling is used in its formation, though it may be otherwise formed, as by casting, it comprises lateral surfaces 16 running lengthwise of the jaws and presenting, as illustrated in FIG. 4, rounded downwardly facing surfaces which have a clamping function. Simultaneously there may be milled a longitudinally extending groove 18, the milling also forming as a continuation of the surfaces 16 the longitudinal surfaces indicated at 20, while in the formation of the groove 18 side surfaces for the groove are provided at 22. The further result of the milling is to provide rounded longitudinally extending ribs as indicated at 24. As will be noted from FIG. 4, the surfaces 22 are concave as viewed in this transverse section and as will appear form outer walls of pockets. The surfaces 20 also have at the roots of the downwardly extending ridges concave portions which also tend to form pockets.
Passing next to the aspects of the lower jaw 10 formed also by milling, this has upwardly convex longitudinal lands 26 while milled inwardly of the lands are grooves 28 having concave walls 30, the grooves conjointly forming a ridge 32 the flanks of which are concave as indicated at 34.
All of the foregoing structural aspects extend longitudinal, and when the jaws are in completely closed position, with the lands 16 and 26 in contact, there will be longitudinally extending pockets as indicated at 36 which have enlarged transverse dimensions as compared with the dimensions of the passages between the ribs and the roots of the rib-receiving grooves. Other pockets of similar dimensions but enlarged with respect to adjacent passages, as viewed in the transverse section, are provided at the regions of the surfaces 30.
So far described have been only the longitudinally extending aspects of the jaw structures. Following the formation of these, as by milling, transverse cuts are made by milling or filing to produce teeth 38 in the ridges of the upper jaw and teeth 40 in the ridge of the lower jaw as will be seen most readily in FIG. 3, these teeth respectively having between them the hollow transverse grooves 42 and 44. The teeth are desirably rounded at their tips. In effect, there are then ridges of rounded teeth which appear rounded in both longitudinal and transverse sections. The matter of rounding of the teeth is mentioned particularly since even though they are rounded effective gripping is secured as will appear more fully later; but even if they are not rounded, the construction is such that cutting or penetration of the tissues is avoided by reason of the reception of the teeth in the grooves with clearances insured by the fact that closing movement is always limited at least by the longitudinally extending lands 16 and 26. Rounding is not essential, but it may be provided in those instances in which damage to very delicate tissues is to be minimized.
While not essential, it is usually desirable to have the teeth staggered in their longitudinal array as indicated in FIG. 3, though this is by no means essential, since, as will be evident from FIGS. 4 and 5, even during operation they are not in any effective shearing action with respect to each other. The staggering of the teeth does produce a more tortuous condition of the tissues enhancing the gripping action.
The production of effective gripping action will be best made clear from consideration of FIG. 5 in which the jaws of FIG. 4 are illustrated as clamping a vessel T which may be assumed to contain a liquid such as blood. The vessel T is tightly clamped as illustrated at T1 by the rounded lands 16 and 26 at both sides of the jaws. It will be evident that this action by closing off the vessel at two regions will trap in the intermediate region a quantity of the liquid. As the jaws are moved to this clamping condition, it would be noted that at the lower edge of the downwardly extending ribs, having the teeth 38, there will be some enlargement of the vessel at T3 , but most significantly there will be enlarged portions of the vessel at T4 in the pockets 36 previously described which retain their pocket form though now somewhat different in shape than as they appear in FIG. 4 wherein the jaws are shown fully closed. There is also some enlargement at T2.
What is illustrated in FIG. 5 is somewhat diagrammatic in that it is quite difficult to show the distortions which are produced, and desirably, by the fact that the longitudinally extended ribs are provided with teeth. FIG. 5, therefore, is to be visualized as involving some bulging of the clamped vessel forwardly and rearwardly of the rounded tips of the teeth.
What is significant is that it will be evident that even though the surfaces engaging the vessel T are rounded, a slipping movement of the clamping surfaces with respect to the vessel will be inhibited by the fact that in order for this to occur it would be necessary that substantial changes in volume and transverse dimensions of the vessel T would have to occur, and these changes are resisted by the elasticity of the walls of the vessel and by the necessity for compressing portions of the vessel with translation of the contained liquid. The operation is somewhat analogous with that which would be required to pull rubber tubing through an orifice substantially less in area than the overall cross section of the tubing. It should be noted that the resistance to this type of movement is not dependent on the existence of sharp edges or sharp points; by virtue of this damage to the tissues may be avoided.
While reference in FIG. 5 has been specifically made to a vessel which may contain a liquid, it will be clear that the matter of compression and necessary restriction for movement would apply to hold all types of body tissues which have the properties of being compressed or distorted with elasticity which will resist these deformations.
While the construction has been described as involving two ridges on one jaw and a single ridge on the other, with corresponding receiving grooves, more ridges and grooves cooperating in the same fashion may be provided to secure more extended clamping.