Dual reamer holder for surgical use

A surgical tool holder has a shank having a central axis, a first driveable end and second coupling end. The second end has a coupling device having interfaces each for mating with corresponding structures on the inside of a hollow reamer. The interfaces mate with centering structures at or near a base end of each tool, the tool being held in functional assembly to the shank by a releasable locking mechanism.

BACKGROUND OF THE INVENTION

This invention relates to surgical tool holders, and more particularly, to holders of rotary surgical cutting tools.

Surgical tools and their respective holders have to be kept clean and sterile before any use in a hospital environment in order to minimize risk of transfer of disease or infection from patient to patient following the emergence of certain “prions” that are not killed by normal hospital sterilization and thus need to be physically removed through washing and rinsing. A surgical tool, for example for preparing for the fitting of a hip prosthesis, works in a medium which causes considerable soiling of the tool and of the tool holder. Despite the importance of doing so, the thorough cleaning of these devices is difficult. Surgical tool holders of the prior art are designed such that washing and rinsing are generally not an effective way of cleaning the tool. This is due to the small spaces left between component parts which allow only minimal access by cleaning agents.

Further, among the many different styles of reamers used by surgeons in orthopaedic surgical operations, there are two that are particularly pervasive, yet which present different interfaces to the holders, thus not permitting a single reamer holder to be able to fasten to the two different interfaces. This requires that the two reamers each have a dedicated holder, which adds to the bulk and expense of surgical tool kits.

What is needed therefore is a surgical tool holder which is quickly and simply disassembled for cleaning and sterilization. Still further, what is needed is a dual reamer holder capable of holding the two different styles of reamers which are pervasively used in orthopaedic surgery.

The surgical tool holder of the invention has a shank having first driveable end and second coupling end, a coupling device mounted on the coupling end, and a locking mechanism. The coupling device has at least two pairs of bayonet interfaces spaced apart from the central axis. Each interface is made up of at least a portion of a slot having a two-tiered opening transverse to the central axis. The two-tiered opening is of a form so as to be able to receive corresponding elongated structures of at least two types of reamer tools, at the selection of the user. The corresponding structures are elongated in a direction substantially perpendicular to the central axis.

In another aspect of the invention, the locking mechanism in made up of an annular capture component, a spring, a locking sleeve which slides on the shank, and a locking device. The capture component is mounted so as to slide along the shank and includes two pairs of longitudinally protruding pins, the matching pin to the pair being positioned 180 degrees apart. In a preferred configuration, the four pins are spaced apart evening on a circle centered on the axis of the shank.

The locking device cooperates with the capture component so as to lock the tool onto the interface. The spring biases the capture component in a locking direction and bears on the locking sleeve. The locking sleeve is disengageably lockable to the shank via a connection device. The connection device is preferably a bayonet mechanism.

The object of the invention is to enable quick disassembly for cleaning and component sterilization.

Another object of the invention is to provide one holder capable of holding the two pervasively used hollow reamers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Referring now toFIG. 1, the dual surgical reamer holder10of the invention is shown. The holder10connects to a surgical tool12or12′ to enable controlled manipulation of that tool. The holder10has a shank14having a coupling end16, a drive interface20attached to an opposite end22(shown in phantom lines) of the shank, a coupling device24and a locking mechanism26. The coupling end16has a series of bayonet grooves30therein, cut transverse to the central axis27of the shank14, and having a two-tiered form in that there are two surfaces presented for receiving an elongated cross bar31,53of an OTHY™-type or PRECIMED™-type of reamer tool12or12′. The locking mechanism26is made up of a capture sleeve32, a helical compression spring34, a locking sleeve36all of which slide along the shank14, and pin receiving holes35. Preferably, to ensure that the tool12′ is retained in an axially aligned relationship with the holder10, a central recess41capable of receiving a boss11on the tool12′ is centrally disposed in the coupling end16of the shank14.

The annular capture sleeve32mounts so as to slide along the shank14. Pins33are mounted in the capture sleeve32and enter into the corresponding holes35in the coupling end16, thus preventing relative rotation of the sleeve32with respect to the shank14.

Tool12has centering bars40, also known as cross bars31, which are received into recesses55in the capture sleeve32, and then locked into the recesses when the capture sleeve is biased up the shank into a locked position, thus ensuring that the cross bar is locked into the bayonet groove30. Note that each groove30has a recess53in order to capture cross bars31. The spring34biases the capture sleeve32in a locking direction, bearing against the locking sleeve36. The locking sleeve36is disengageably lockable to the coupling end16of the shank14via a bayonet mechanism, which includes a bayonet slot50and a locking pin52. The bayonet slot50is cut in the coupling end16of the shank14. The locking pin52is press fit into the locking sleeve36.

The locking sleeve36locks over the shank14near the coupling end16. The shank14has a longitudinal groove37within which the bayonet pin52slides so as to enable the locking pins52or52′ to freely slide along the shank14when the locking sleeve is unlocked and slid back along the shank, in order to provide cleaning access to all surfaces of the locking mechanism26.

Referring now toFIG. 2, all recesses30receive the cross bar31of the PRECIMED™ tool12(shown inFIG. 4) and specialized recesses30′ receive the boss11and rectangular arm13(shown inFIG. 3) of the OTHY™ reamer12′. Note that the recesses30′ include a narrow rectangular arm receiving portion53. Further, pins52′ include small nipples58on their ends, which enable the pins to lock in the cross bars31more fully, while rising along the shank14to the same position (approximately) as is the case when the arms13of the “OTHY” product are captured, thus ensuring that the visual impression of locking is consistent when locking either product into the holder10, despite the different geometric configuration of the interfaces. Thus, the current embodiment requires that the user place the arm13of the “OTHY”™-type tool in the appropriate corresponding recesses30′.

The pins33and33′ are chamfered or tapered in order to wedge the rectangular arm13or the bar31into the corresponding recesses53or55respectively, so as to eliminate play.

Referring now toFIG. 5, optionally, chamfered surfaces60facilitate the insertion of the rectangular arm13or the bar31into the corresponding recesses30or30′.

Referring now toFIG. 6, it can be clearly seen (see alsoFIG. 2) that grooves30have recess53, these recess each have a two-tiered structure. A first tier T1of the opening which the groove30defines accommodates the rectangular cross section68“OTHY”™-type reamer (seeFIG. 5), capturing the rectangular cross section68(shown in dashed lines in the figure) against three surfaces70,72, and the locking pin33′. A second tier T2, captures and locks a round bar31(shown in dashed lines in the figure) of the “PRECIMED”™ cross bar reamer interface against rounded surface78and the pin33′.

In operation, the cross bar31or the bar13enters the appropriate bayonet groove30or30′ and is turned so as to move into the recess55or the receiving portion53, as the case may be. The tool12or12′ is locked in this position when the capture sleeve32is raised into a position in which the pins33and33′ pass through the holes35and into recesses30and30′ of the holder10so as to lock the tool in place inside the recess.

To unlock the holder10, the locking sleeve36is urged against the bias of spring34so as to lift it out of a bayonet seat51, and then twisted so as to move the pin52out of the bayonet slot50in the coupling end16of the shank14. The locking sleeve36may then be slid back along the shank14, releasing the spring34and the sleeve32, and thereby providing cleaning and sterilization access to the recesses that might otherwise not be accessible.

In an advantage of the invention, the bayonet mechanism holds the locking sleeve36and thus the spring34in an operational position, as well as enabling quick disassembly for cleaning and component sterilization.

In another advantage of the invention, the holder is adapted to hold more than one tool interface, thus minimizing the bulk and weight of a surgeon's tool kit.

In another advantage, the holder10of the invention minimizes play and maximizes alignment with the turning axis27.

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. The elastic devices used of course can be selected from a large variety of equivalents to a helical, compression spring, including, for example, leaf springs, flat springs, multiple compression springs, just to name a few. Still further, the connection mechanism can be substituted for a variety of connection mechanisms such as a threaded connection mechanism, a clasp, spring detents, or even magnetic retention devices. Accordingly it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.