Instrument holder for surgical instrument

Instrument holder comprising a shank (1) equipped with a head (2) designed to receive an instrument and a locking component (4) pushed against the head by a spring (9) bearing on a ring (11) sliding on the shank, and having means of connection (8, 12) on the shank which is engaged by rotation of the ring, in such a way that the release of the ring allows the locking component, the spring and the ring to slide freely in order to permit cleaning of the instrument holder.

BACKGROUND OF THE INVENTION
 The invention relates to an instrument holder for a surgical instrument,
 comprising a shank equipped with a head designed to receive an instrument,
 and an annular locking component mounted so as to slide about the shank,
 under the head, equipped with locking means which cooperate with the head
 so as to lock the instrument on the head, and pushed against the head by a
 helical spring.
 An instrument holder of this type is known in particular from U.S. Pat. No.
 5,658,290 and U.S. Pat. No. 5,236,433, the contents of which are
 incorporated by reference.
 A surgical instrument, for example for preparing for the fitting of a hip
 prosthesis, works in a medium which causes considerable soiling of the
 instrument and the instrument holder. Moreover, a surgical instrument
 holder must be cleaned very frequently and very carefully in order to
 avoid any risk of infection. However, cleaning of surgical instruments is
 difficult, in particular cleaning of the space between the shank and the
 locking component on account of the presence of bone debris and coagulated
 blood.
 SUMMARY OF THE INVENTION
 The object of the invention is to provide optimum conditions for rapid
 cleaning.
 To this end, the instrument holder according to the invention is
 distinguished by the fact that the thrust spring bears on a ring sliding
 on the shank, and that the shank and the ring have means of connection set
 in use manually by rotation of the ring, in such a way that the release of
 the ring allows the locking component, the spring and the ring to slide
 freely on the shank. This almost instantaneous disassembly of the
 component parts of the instrument holder allows it to be thoroughly and
 quickly cleaned.
 According to a preferred embodiment of the invention, the shank has, under
 the head, a section with a diameter greater than the diameter of the rest
 of the shank, on which section the ring is fixed by a bayonet fastening.
 The play of the components making up the locking means on the shank permits
 good cleaning without it being necessary to remove these components from
 the shank, which avoids the risk of losing a component or mixing them up,
 and it obviates the need to fit the components back on the shank. The
 fastening and release of the ring take place instantaneously, which
 represents a saving in time. This makes it possible to ensure that a
 complete kit of instruments is not rendered unusable because of a single
 component being inoperative.
 The head and the fastening and locking means of the instrument can be
 designed in many ways. These means do not form part of the actual
 invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
 The instrument holder shown comprises a cylindrical shank 1 at one end of
 which a head 2 is fixed which is identical to the head described in U.S.
 Pat. No. 5,658,290, the content of which is incorporated by reference.
 This head has a central recess, the head forming a crown around this
 recess. This crown has four bayonet catches 3 diametrically opposite in
 pairs. A reamer analogous to the reamer shown and described in U.S. Pat.
 No. 5,658,290 is fixed in these catches 3. The reamer is locked in the
 catches 3 by an annular locking component 4 equipped with a plate 5 having
 four parallel fingers 6 which pass through the head 2 in order to close
 the bayonet catches 3, as is described in U.S. Pat. No. 5,658,290.
 The locking component 4 does not slide directly on the section of the shank
 seen in FIG. 1, but on a section 7 with a greater diameter than the
 diameter of the rest of the shank. This section 7 can consist of a tubular
 component arranged on the shank 1. At least one bayonet catch 8 is formed
 at the end of the section 7 remote from the head 2. These catches are
 preferably at least two in number and diametrically opposed to facilitate
 assembly, as will be seen below. Also arranged around this section 7 there
 is a helical spring 9 which engages in a frustoconical widened part 10 of
 the locking component 4 and bears against this locking component, the
 median part of which slides freely on the section 7. The instrument holder
 is completed by a ring 11 which also slides on the section 7 and is
 equipped internally with a radial stud 12, that is oriented in the
 direction of the shank 1.
 Starting from the disassembled position shown in FIG. 1, and in order to
 assemble the instrument holder, the locking component 4 is brought under
 the head 2, engaging its locking fingers 6 through the head, then, with
 the ring 11, the spring 9 is pushed against the locking component 4 and
 this spring is compressed, at the same time turning the ring 11 to the
 left until its stud 12 engages in the bayonet catch 8 respectively in one
 of the bayonet catches, in which it fastens by holding the ring 11 which
 is pushed rearward by the spring 9. The instrument holder can then be used
 as is described in U.S. Pat. No. 5,658,290. The frustoconical widened part
 10 gives a grip for the thumb and index finger for pulling the locking
 component 4 back counter to the action of the spring 9 in order to release
 the instrument fixed on the instrument holder.
 Conversely, in order to disassemble the instrument holder, it suffices to
 push the ring 11 forward counter to the action of the spring 9 and to turn
 it in the direction of the hands of a watch in such a way that its stud 12
 is pushed out of the bayonet catch 8 by the spring 9.
 It will be seen that assembly and disassembly of the instrument holder are
 effected instantaneously and can be done using one hand.
 As is shown in FIG. 1, the shank 1 allows the components 4, 9 and 11 to be
 removed totally from the shank. Given the substantial play of the
 components 4 and 11 on the shank 1, such complete disassembly is not
 necessary for cleaning purposes. It i s therefore possible to provide an
 abutment at the end of the shank in order to hold the components on the
 shank.
 The end of the shank remote from the head 2 is shown as being cylindrical,
 but it can have another shape, in particular a hexagonal cross section for
 fastening the instrument holder on the means for driving the instrument
 holder in rotation.
 The ring 11 could be made integral with the shank by screwing, that is to
 say having a screw thread in the ring and on the part 7.
 The head 2 and the fingers 6 are only one example from all the possible
 means for connection of an instrument.
 Although illustrative embodiments of the invention have been shown and
 described a wide range of modification, change and substitution is
 contemplated in the foregoing disclosure and in some instances, some
 features of the present invention may be employed without a corresponding
 use of the other features. Accordingly it is appropriate that the appended
 claims be construed broadly and in a manner consistent with the scope of
 the invention.