US 1920821 A
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1, 1933- J. -..l. s. WASSENAAR DISTRACTION BONE FORCEPS Filed Dec. 31, 1931 Patented Aug. 1, 1933 rarest or ies DISTRACTEGN BONE FORCEPS Jan .lacob Stephanns Wassenaar, Pilgrims Rest, Transvaal, Union of South Africa Application December 31, 1931, Serial No. 584,215, and in the Union of South Africa September 6 Claims. (01. 128-432) This invention relates to improvements in surgical instruments of the type known as distraction bone forceps. The present invention provides an instrument which is simple in construction, positive in its action, and is readily dismantled for purposes of cleaning and sterilization. Furthermore, the manner in which the jaws of the instrument are designed to grip the bones, precludes any possibility of their slipping and damaging the tissue covering the same.
The instrument comprises two straight jaw members whose shanks are rotatable and slidable in guide brackets, which brackets are connected by a screw member by which means the distance between them may be varied and adjusted at will within predetermined limits. To provide rigidity a slidable guide member preferably of square section passes through suitable holes in bosses on each guide bracket at right angles to said jaw member and thus retains the two jaw members in parallel relationship with one another, although allowing free movement of said members either toward or away from one another under the influence of the screw member.
The ends or" the jaw members are provided with fixed curved forked or claw-like jaws with which a movable sliding jaw member co-oper ates. The shanks of said jaw members are bored out centrally and a cylindrical projection integral with said movable jaw slides within the portion of said bore adjacent said fixed jaw members. A slot parallel with the axis of said shank allows free movement for the connecting lweb between the jaw proper and the sliding cylindrical portion. A screwed rod provided with a ball shaped end engages movably with a socket in the end of said sliding cylindrical projection and provides the means whereby the movable jaw is caused to approach or recede from the fork-like fixedjaw members for purposes of gripping 'or releasing the bone ends.
The shanks of the gripping members are further provided with grooves parallel with their axes and on opposite sides thereof. A set screw located in the boss on each guide bracket is adapted to engage with these grooves and to lock said members where desired. Further, circular grooves may be provided to enable the said member to rotate with the end of the set screw in engagement therewith.
To enable the invention to be more readily understood reference is made to the accompanying sheet of drawing, in which is shown one I construction embodying the invention.
Fig. 1 is an elevation of the instrument in an operative position.
Fig. 2 is an end elevation of one of the guide brackets and part of the jaw shank.
Fig. 3 is the thumb screw whose end engages in the slots in the shank. g s
Fig. 4. is an elevation of the screwed rod operating the movable jaw.
Fig. 5 is a part sectional elevation of one fixed jaw and shank with movable jaw and operating square holes 8 in the boss 18 on each guide bracket while the hand operated screw 5 provides the means whereby the parallel distance between the jaw members may be varied. It
will be noted that the screw 5 is rotatably located in the guide bracket 2, while bracket 1 is tapped taco-operate with said screw member 5.
The movable jaw is shown at 9 and is actuated by the screw rod 12 whose ball end 11 engages with a socket 10 on the integral cylindrical projection 17 which is slidable in a bore 13. 5
The longitudinal grooves are shown at 14 while one circumferential groove is shown at 15. A set screw 16 screws into each bracket member in such a manner that its end is adapted to engage with said grooves as desired. One or more cir- 9'0 cumferential or longitudinal grooves may be provided.
Fig. 1 shows the instrument in use for the purpose of bringing the two ends of a fractured bone into direct alignment and contact. The
screw 5 is first of all rotated so as to bring the ends clear of one another. One of the jaw members 3 may then be moved in its guide bracket until the two ends of the bone are in alignment,
when the screw 5 may again be operated to bring the two ends into direct contact for bone plating, jointing and other purposes.
The serrations or teeth on the gripping faces- 01" the fixed jaws lwill preferably be at an angle to the shank as shown in Figs. 5 and 6 which will further aid in preventing said jaws slipping longitudinally of bones with which they are in gripping contact.
What I claim is:-
1. An improved surgical instrument of the dis- 1 traction bone forceps type, comprising two straight gripping members terminating at one end in fixed forked claw-like jaws, separate guide brackets in which said members are slidable and rotatable, a transverse guide rod slidably connected to the bracketsvand retaining said jaw members in parallel relationship, a hand operated rod threadedly connecting said guide brackets to adjust said parallel relationship, and a hand operated screw rod cooperating with a tapped bore in the other end of each jaw member and having a ball at the inner end and a cylindrical sliding member having a curved jaw member positioned to cooperate with said forked claw-like jaws for bone gripping purposes, and also having a socket in which said ball end of the hand operated rod is engaged.
2. An improved surgical instrument, according to claim 1, wherein said cylindrical sliding member is located in a bore adjacent the fixed claw-like jaws and a longitudinal slot in the walls thereof forms positioning and guiding means for the said cylindrical sliding member.
3. An improved surgical instrument as claimed in claim 1, wherein the slidable guide rod is of square section.
4. An improved surgical instrument as claimed e in claim 1, wherein the hand operated screwed her is located inra bore adjacent the fixed clawlike jaws and a longitudinal slot in the walls thereof forms positioning and guiding means for the said cylindrical sliding member and wherein said fixed claw like jaws and said movable jaw members have serrations or teeth on their inner surfaces arranged at an angle to the axis of the jaws, to prevent said jaws slipping longitudinally.
JAN JACOB STEPHANUS WASSENAAR.