1. Field of Art
This invention relates in general to surgical tools, and in particular to rotary powered surgical resection tools.
2. Description of the Prior Art
Surgical resection tools have been used for resecting, or cutting, bone and tissue during surgical procedures. Many such tools employ pneumatic or electric motors to rotate the cutting elements of these tools. In their most basic form, such surgical instruments comprise a rotary motor having a rotary shaft, or spindle, a dissecting tool having a cutting element which is rotated by the motor, a bearing tube to surround and support the dissecting tool, and a means for connecting the dissecting tool to a spindle of the motor. A standard type of collet chuck is typically mounted to the motor spindle for securing the dissecting tool to the motor. The collet chuck is mounted within a base of a stationary housing which is threadingly secured to a stationary portion of the motor. The bearing tube is mounted to the base, typically by a threaded connection.
In order to replace a dissecting tool, the base has to be unscrewed from the motor so that the collet chuck can be accessed. The bearing tube is usually secured to the base by a threaded connection, and is often sized so that it cannot be removed from over the resecting tool because of the size of the cutting element. Wrenches or other hand tools are used to threadingly secure and release bearing tubes from the base, and the base from the motor. Collet chucks for securing the dissecting tool to the motor are usually provided with a collet nut and slotted sleeve, which are mounted to the rotary motor spindle. The collet nut must be rotated for some distance around the slotted sleeve for the dissecting tool to be released for removal from the slotted sleeve and the spindle. Usually a wrench or other type of hand tool is used to rotate the collet nut. Once the dissecting tool is removed and replaced, the collet nut is rotated to clamp the dissecting tool within the slotted sleeve and to the spindle. The base is also rotated to secure the bearing tube to the stationary portion of the motor.
It is often necessary to replace dissecting tools many times during a given surgical procedure. This requires that the above procedure be carried out frequently. It is also often required that bearing tubes be replaced with other bearing tubes of various lengths and diameters to accommodate dissecting tools of various sizes. Replacing the bearing tube requires that another threaded connecting be broken and then made up. Replacing dissecting tools and bearing tubes is usually a time consuming task since wrenches and rods are often necessary to break and make up the threaded connections securing dissecting tools and bearing tubes to surgical resection tools. What is needed is a means for coupling dissecting tools, bases and bearing tubes within a surgical resection tool so that the dissecting tools and bearing tubes may be quickly and easily removed and replaced.