Customized surgical fixture

Abstract

A customized surgical fixture ( 400 ) is formed by scanning a body to form a three-dimensional image of the body, and then identifying in the image a target ( 310 ) in the body, and mounting points or structures ( 330 ) on the body. A model, such as a computer solid model, of the fixture ( 400 ) is specified in accordance with the locations of the target ( 310 ) and mounting structures ( 330 ) or points. The fixture ( 400 ) is formed in accordance with the model of the fixture ( 400 ), for example using a rapid prototyping and tooling machine. When attached to the body, the fixture ( 400 ) can be used to guide a surgical instrument ( 610 ) into the body, for example, by using a mechanical guide ( 600 ) attached to the fixture ( 400 ) or using a remote sensing device ( 1300 ) that tracks the relative position of the customized fixture ( 400 ) and the surgical instrument.

1 - 19 . (canceled)  
   
   
       20 . A method for designing a customized medical fixture comprising: 
 (a) locating a first plurality of devices attached to a body from a scanned image of the body;    (b) determining desired locations for a second plurality of devices relative to the locations of the first plurality of devices;    (c) computing a digital model of the shape of medical fixture wherein 
 the shape of the fixture is adapted for placement on the body in a predetermined location relative to the first plurality of devices,  
 the shape of the fixture includes structures for attaching the second plurality of devices, and  
 the shape of the fixture being such that when the second plurality of devices are attached to the medical fixture at said structures and the fixture is placed at said predetermined location, the second plurality of devices are at the desired locations of the second plurality of devices relative to the locations of the first plurality of device.  
   
   
   
       21 . The method of  claim 20  wherein the second plurality of devices includes a plurality of bone anchors attached to bone structures of the body.  
   
   
       22 . The method of  claim 21  wherein the first plurality of devices includes a plurality of tracking markers.  
   
   
       23 . The method  claim 21  wherein the shape of the fixture is adapted for attachment to the bone anchors.  
   
   
       24 . A method for stereotactic surgery comprising: 
 locating a first plurality of devices attached to a body from a scanned image of the body;    fabricating a medical fixture customized for the body, 
 the fixture including a plurality of structures for attaching a second plurality of devices,  
 the fixture being adapted for placement on the body in a predetermined location relative to the first plurality of devices such that when the fixture is placed in said predetermined location the structures of attaching the second plurality of devices are in a known geometry relative to the first plurality of devices;  
   attaching the second plurality of devices at the plurality of structures on the fixture;    positioning the customized medical fixture on the body at the predetermined location;    tracking locations of the second plurality of devices; and    computing a location of the body based on the tracked locations of the second plurality of devices, the known geometry, and locations of the first plurality of devices attached to the body.