Medical forceps

Medical forceps for example for excision of tissue in arthroscopic applications, comprises a jaw element rigidly connected to a shaft and a movable jaw element which is operated via a rotary rod extending through the shaft and a first bevel gear secured to the rod within a proximal housing. The first gear meshes with a second bevel gear which is rotated by an operating lever, via a push rod and a radial lever arm connected to the second bevel gear.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to medical forceps, in particular for arthroscopic 
application, wherein a fixed jaw element situated at the distal extremity 
of a shaft has cooperation with it a movable jaw element which is actuated 
via a rotary rod extending through the shaft and a gear within a proximal 
housing by means of operating handles. 
2. Description of the Prior Art 
Such forceps operated by means of operating handles for the purpose of 
excising tissue or the like are known, in which connection the procedure 
followed in an embodiment according to the German Utility Model No. 83 11 
392 is such that the rigid branch of the operating handle is equipped with 
a guided toothed bar or rack which is coupled to the movable handle via a 
link. The rack is entrained by actuation of this handle and operates a 
proximal gear situated on the rotary rod, whereby the movable distal jaw 
element is operated for removal of tissue. Because of the exposed rack, 
soiling of the moving parts may occur and the functionality may be 
restricted thereby. In the case of other clippers or forceps, the 
disadvantage again arises that they require comparatively high production 
costs because of their structure. 
SUMMARY OF THE INVENTION 
It is an object of the invention to produce a medical cutter or forceps, 
particularly for arthroscopic applications which is simple and economical 
to produce and in which all operating elements are protected against 
soiling and failure. 
According to the invention, this object is achieved in the case of the 
medical forceps referred to in the foregoing in that the rotary rod 
carries a bevel gear within a proximal housing, which bevel gear meshes 
with a second bevel gear installed on a transverse spindle, which second 
bevel gear has a radial lever arm articulated on the one extremity of a 
push rod, whose other extremity is jointedly coupled to the upper arm of 
the movable operating handle. 
All the parts essential to uncomplicated entrainment of the movable jaw 
element are thus situated within a housing in a protected manner.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The medical forceps comprise a tubular shaft 1 with a fixedly attached jaw 
element 2 firmly joined to its distal extremity. A rotary rod 3 extends 
through the shaft 1 and has attached to its distal end a movable jaw 
element 4. At its proximal end, the shaft 1 passes into a housing 5, and 
the rotary rod 3 is secured by a grub or set screw in a hub 6 of a bevel 
gear 7. The rotary rod 3 passes through a rotary bearing 21 at the 
proximal end of the shaft 1. The shaft 1 is secured in the proximal 
housing 5 in a replaceable manner by means of a grub or set screw 19, and 
the housing 5 has installed in it a second bevel gear 8 mounted on a 
transverse spindle or axle 9 and meshing with the gear 7. The bevel gear 8 
is coupled to a radial lever arm 10 which is articulated on one end of a 
push rod 11. The other end of the link or push rod or link 11 is coupled 
to the upper arm 12 of the movable operating handle 13, which is pivotally 
attached by a spindle 14 to a second operating handle 15 which in turn is 
rigidly mounted on the housing 5. 
The gear 8 is rotated via the push rod 11 and the lever arm 10 by opening 
(i.e. pushing apart) the operating handles 13, 15 and thereby turns the 
gear 7 and the rotary rod 3 to open the forcep jaws 2, 4. For removal of 
tissue, the jaws 2,4 are closed by pressing the handles 13, 15 together 
(FIG. 1). 
According to the drawings, the hub 6 of the bevel gear 7 is installed or 
journalled in a cylindrical recess 5a of the housing 5 which is rigidly 
joined to the operating handle 15. According to FIGS. 1 and 2, the housing 
5 is enclosed by means of covers 16, 18. The passage 17 for the movable 
handle 13, which passes through the housing 5 and the external cover 18, 
may be sealed by means of elastic covers.