Computer Assisted Therapies
3D Computer-Assisted Preoperative Planning for Distal Radius Osteotomies
A three-dimensional preoperative planning system has been developed and used in conjunction with an intraoperative image-guided system for distal radius osteotomy. The planning system permits the surgeon to determine the exact location of drill holes for a given fixation plate used in surgery. A plan can be imported into the guidance system which ensures that surgical results will match what was planned preoperatively. A laboratory study comparing the accuracy and reproducibility of this corrective procedure has shown that the computer-assisted surgical approach gave significantly more accurate and reproducible results than the traditional method. Clinical trial outcomes are also encouraging. This study indicates that three-dimensional planing is essential for achieving accurate surgical results.
- H. Croitoru. 3D Computer-Assisted Preoperative Planning for Distal Radius Osteotomies. Master's thesis, Queen's University at Kingston, 1999.
- H. Croitoru, R. E. Ellis, C. F. Small, R. Prihar, and D. R. Pichora. Fixation-based surgery: A new technique for distal radius osteotomy. Journal of Computer Aided Surgery, 6:160-169, 2001.
- H. Croitoru, R. E. Ellis, C. F. Small, and D. R. Pichora. Fixation-based surgery: A new technique for distal radius osteotomy. In Medical Image Computing and Computer-Assisted Intervention - MICCAI 2000, pages 1126-1135. Springer Lecture Notes in Computer Science #1935, 2000.
A Preoperative Planning System for High Tibial Osteotomy
A three-dimensional pre-surgical planner and image-guided surgery system for high tibial osteotomy has been developed. The planning software permits a surgeon to establish the tibial axes, plan the corrective osteotomy, and visualize both the preoperative state and the predicted postoperative state in three dimensions. The parameters that describe the placement and orientation of the osteotomy resection planes can be transmitted to an accompanying guidance system that allows the surgeon to accurately perform the planned procedure. Tests were performed in vitro; to compare the accuracy of the computer-enhanced technique to the traditional technique, and an in vivo; pilot study has been initiated. The computer-enhanced techniques produced a significant reduction in the error of correction and is simple to use while performing the surgical procedure. The work indicated that three-dimensional planning and surgical performance of high tibial osteotomy is essential to the accuracy of the procedure.
- R. E. Ellis, C. Y. Tso, J. F. Rudan, and M. M. Harrison. A surgical planning and guidance system for high tibial osteotomy. Journal of Computer Aided Surgery, 4(5):264-274, 1999.
- C. Y. Tso. A Preoperative Planning System for Osteotomies. Master's thesis, Queen's University at Kingston, 1997.
- C. Y. Tso, R. E. Ellis, J. F. Rudan, and M. M. Harrison. A surgical planning and guidance system for high tibial osteotomies. In Medical Image Computing and Computer-Assisted Intervention - MICCAI'98, pages 39-50. Springer Lecture Notes in Computer Science 1496, 1998.
Computer-Assisted Planning and Guidance of the Ilizarov Method
The Ilizarov method is used to correct various bone deformities by using an adjustable mechanical frame to simultaneously align and distract bone fragments after the bone has been cut. We have adapted the idea of fixation-based surgery, which requires computer-assisted planning and guidance, to the Ilizarov method as used with the Taylor spatial frame.
This work incorporates the kinematics of the Taylor frame, which is a type of Stewart platform, into the planning and application phases of surgery. Using 3D models derived from a CT scan of the deformity, a surgeon can use a preoperative software system to plan the correction and determine the placement of the frame. We have developed techniques and software for inverting the correction, finding the kinematics of the Taylor frame so that the frame fits onto the deformed bone, and planning the correction schedule that will gradually remodel the deformity into the desired correction.
We used a computer guidance system to accurately attach the frame to model of a deformed bone. In a laboratory study that compared the accuracy and repeatability of the new method, we found that the computer-assisted technique was more repeatable than the traditional technique and had a smaller range of errors. The study also showed that the computer-assisted technique required almost no intraoperative X-ray exposure and that complex corrections could easily be achieved.
- O. O. Iyun. Computer-assisted Planning and Guidance of the Ilizarov Method with the Taylor Spatial Frame. Master's thesis, Queen's University at Kingston, 2002.
- O. O. Iyun, D. P. Borschneck, and R. E. Ellis. Computer-assisted correction of bone deformities using a 6-DOF parallel spatial mechanism. In T. Dohi and R. Kikinis, editors, Medical Image Computing and Computer-Assisted Intervention - MICCAI 2002, pages 232-240. Springer Lecture Notes in Computer Science #LNCS 2488, 2002.