Medical syringe abstract
A tubular supply container for use in a medical syringe to dispense
bone cement has a pipe formed tube with a slidable plunger. A smaller
diameter injection pipe is removably secured to the forward end
of the pipe formed tube. A funnel may also be applied to the forward
end of the tube to assist in filling the container or may be placed
on the rear end to serve as a stand.
Medical syringe claims
We claim:
1. A tube-type supply container for viscous media, in particular
bone cement, that is adapted to be inserted in an appliance provided
with a manually actuable push rod, said supply container comprising:
a cylindrical tube, both ends of said tube being open, one of said
ends having first thread means adjacent thereto;
injection pipe means including a relatively elongated pipe portion
of relatively small diameter and a conically flared portion, said
pipe portion being formed of a shearable, elastic material, said
conically flared portion having second thread means by which the
conically flared portion can be connected to one of the ends of
said cylindrical tube by coaction with said first thread means;
a plug-like piston that is sealingly displaceable within said cylindrical
tube and adapted to be actuated by said push rod; and
a funnel member having a cylindrical portion adapted to be slid
on the outer side of either end of said cylindrical tube and having
an abutment in its interior cooperating with either end face of
said cylindrical tube.
2. A tube-type supply container set forth in claim 1 wherein said
conically flared portion includes a tube-like extension adapted
to be introduced into said elastic pipe portion and secured by a
clamp.
3. The container according to claim 1 characterized in that a thread
means (21) is formed on the outside of the tube (20) and on the
inside of the cylindrical section (13) of the conically flared portion
(12).
4. The container according to claim 1 characterized in that the
abutment is formed of a ring-like band (43) in front of the transition
to a conical part (42).
5. The container according to claim 1 characterized in that the
plunger (30) has a forward cylindrical section (35) and a rearward
formed section with ring-like circular flexible ribs (36), wherein
the diameter of the cylindrical section (35) corresponds to the
inner diameter of the tube (20) and the diameter of the ribs is
somewhat greater than the diameter of the tube.
6. The container according to claim 5 characterized in that the
ribs (36) have sawtoothed surfaces in cross-section, whereby when
seen in the pushing direction, the forward surfaces (37) incorporate
a smaller angle to the longitudinal axis than the rearward surfaces
(38) and the apex of the ribs (36) is formed as a ring surface (39)
parallel to the cylindrical section (35).
Medical syringe description
The invention relates to a tubular sypply container for use in
a medical syringe for viscous media, in particular bone cement.
The apparatus has a pipe-like tube, whose forward end is connected
with a smaller diameter injection pipe, and a sealed and slidably
movable plunger in the pipe-like tube.
A syringe is already known by which a pipe-like tube filled with
a viscous medium is insertable in a channel formed support bar (DE-GM
No. 7607385). In the manipulation of the syringe, a pusher rod
is longitudinally displaceably supported in the thrust of a plunger
in the tube. The known apparatus has the advantage of bringing measured
quantities of sterilized materials in a simple manner within a short
period of time to the desired location. Its use is of particularly
great advantage in orthopedic surgery for the injection of bone
cement in the treatment of bone fractures and/or the insertion of
endoprotheses.
Bone cement is ordinarly manufactured from a pair of powder and
liquid components. The pair of components are initially mixed in
a separate container and subsequently loaded into the pipe-like
tube. This procedure is however proportionately troublesome and
time consuming.
The present invention has as its object to provide a tubular supply
container for a medical syringe for viscous media, which results
in a simple working of the viscous medium.
This object is achieved through the invention in that the forward
end of the pipe-like tube is open and has securing means for the
fastening of the injection pipe.
The invention proceeds from the recognition that the pipe-like
tube open at both ends can be used at the same time as the mixing
vessel. For this purpose the plunger is initially inserted in an
assigned end of the tube and left in the initial position. Thereafter,
the bone cement powder is introduced and the fluid component added.
After the stirring of the mixture the injection pipe is then fastened
on the tube and the assembled arrangement inserted in the syringe,
as is known, for example from DE-GM No. 7607385. The mixing of
the bone cement components in a separate vessel is avoided.
The supply container according to the invention is considered as
a unitary article and is correspondingly formed of appropriate,
but inexpensive plastic material.
With the invention, the injection pipe must be put on the tube
after the production of the mixture, that is, be connected with
the tube. Thus a preferred embodiment of the invention provides
that the securing means comprises a thread, preferably a fast locking
thread. It is of course possible, to provide the injection pipe
with outer threads and the tube with inner threads in order to join
the two parts to each other. It is preferably however, if, according
to a further embodiment of the invention, the thread is formed on
the outer side of the tube and on the inner side of the cylindrical
section of the injection pipe. In order to assure the most advantageous
transition possible between the tube and the injection pipe, another
embodiment of the invention provides that the injection pipe has
a conically flaring section on the rear end, the end of which is
bringable into engagement with the securing means of the wall of
the tube. Between the tube and the injection pipe a funnel shaped
transition is thus produced.
The particular use of the supply container according to the invention
is improved according to a further refinement of the invention in
that a funnel is provided having a cylindrical part which can be
pushed on the outer side of the tube and has a flaring conical part.
On the inside of the cylindrical part a boss is provided which cooperates
with the end surface of the tube. The funnel is set up with the
cylindrical part on the open forward end surface of the tube and
thus facilitates the filling with the components of the bone cement.
After the filling the funnel is removed and pushed on the opposite
end of the pipe formed tube, whereby the boss comes to lie against
the rearward end surface of the tube. The funnel thus serves as
a stand for the tube. The boss, which according to a further refinement
of the invention, is formed from a ring-like band before the transition
to the conical part also prevents falling out of the plunger formed
stop.
After the mixing, the injection pipe is set up and the arrangement
so formed, after removal of the funnel, inserted in the syringe.
The plunger usable for the invention can be formed in suitable
manners and ways. A refinement of the invention thus provides that
the plunger has a smooth forward cylindrical section and has a rear
section formed with ring-like circular, flexible ribs, whereby the
diameter of the cylindrical section corresponds to the inner diameter
of the tube and the diameter of the ribs is somewhat greater than
the inner diameter of the tube. With the insertion of the plunger
in the inner cylinder of the tube, the flexible ribs are deformed
somewhat rearward and inward, so that the plunger is held formlocked
on the inner cylinder of the tube and is also self-holding therein.
An exemplary embodiment of the invention is more particularly explained
with the aid of the following drawings.
FIG. 1 shows a section through a supply container according to
the invention.
FIG. 2 shows a section through a portion of the plunger of the
supply container according to FIG. 1.
FIG. 3 shows a section through another portion of the supply container
according to FIG. 1.
The supply container shown in FIG. 1 is formed of four assembleable
parts, namely a two-part injection pipe 10 a cylindrical tube 20
a plunger 30 and a funnel 40. The tube 20 is proportionately thin
walled cylinder with a continuous inner bore, so that it is open
at both ends. On the forward end a rapid locking thread 21 is formed
on the outside.
For functional efficiency, the injection pipe 10 is formed out
of two parts, namely a proportionately long pipe section 11 with
a proportionately small inner diameter, formed out of a quantity
produced tubing which is cut to the desired length. Its fastening
is shown in detail in FIG. 3. On the rear end the injection pipe
10 is connected with a conical section 12 which overlaps the outside
of tube 20 with a cylindrical section 13 the outside of tube 20.
An inner quick locking thread 14 of the conical section 12 coacts
with thread 21 of the tube 20. On the inside of the cylindrical
section 13 a shoulder 15 is formed against which the edge surface
of tube 20 lies, whereby the inner diameter of the cylindrical section
13 is the same as that of tube 20 so that an even transition is
established between the conical section 12 and tube 20. A boss 16
sits on the narrow portion of the conical section 12 over which
the tubing 11 is drawn (FIG. 3).
The plunger 30 includes a cylindrical ring, which on the forward
end is sealed through a massive disc 32. On the inside of the ring
31 are arranged perpendicularly crossing webs 32 and 33 connected
with the disc formed part 32. From the crossing point of the webs
32 33 extends rearwardly a peg 34 which coacts with a not shown
pusher rod of the syringe.
The plunger ring 31 includes, as is apparent from FIG. 2 a section
35 the outer side of which is smoothly cylindrically formed. It
extends approximately two-thirds of the length of the plunger. Thereafter
are rearwardly attached three ring formed circular ribs 36 which
are sawtoothed formed in cross-section such that the forward surfaces
37 join the longitudinal axis of plunger 30 at a smaller angle than
the rear surfaces 38. The outside the ribs 36 form a smooth ring-formed
section 39 which runs parallel and coaxial to the cylindrical section
35. The outer diameter of the cylindrical section 35 corresponds
to the inner diameter of tube 20. The outer diameter of ribs 36
is somewhat greater than the inner diameter of the tube so that
the ribs 36 with the insertion of the plunger 30 are elastically
deformed rearwardly and radially inward.
The funnel 40 has a cylindrical part 41 the inner diameter of
which corresponds approximately to the outer diamter of tube 20.
A conical part 42 is joined to cylindrical part 42. In the transition
between the cylindrical part 41 and the conical part 42 a ring-like
band 43 formed, which functions as a boss when the funnel 40 is
pushed over one of the two ends of tube 20. When the funnel is pushed
over the forward end, it serves as a filling funnel. When it is
pushed on the rear end, it serves as a stand and simultaneously
prevents the pusher 30 from falling downwardly out of the tube.
The parts 10 20 30 and 40 can be manufactured out of a suitable
plastic material. They are, before the use, preferably individually
placed in a sterilized packing. The injection pipe 11 has a proportionately
long length, for example up to 36 cm. Its material is so selected
that a shortening with a scapel or sharp knife is possible for each
desired length. In this way can also long shaft prostheses be provided.
The fastening of the tubing piece 11 on the boss 16 is apparent
from FIG. 3. The shoulder 16 conically tapers to the forward end
and has in the rear region an annulus (17) for the fastening of
the tubing piece 11 by means of joinder ring 18 of stainless steel.
The tubing piece 11 may also possibly rest sufficiently firmly on
the shoulder 16 without a clamping collar (18) of this type. Customarily
tubing piece 11 and section 12 are assembled at the time of manufacture. |