Abstract
A fluoroscopic based computer enhancement system was designed for accurate insertion of guide wires for hip fracture fixation while decreasing fluoroscopy time. A saw bone model was created. The femur was imaged with fluoroscopy and a three-dimensional computer model was created. The femur, fluoroscopy drum, and drill were tracked with an optical tracking device. Guide wire position was planned on the computer model. Using a tracked drill the guide wire was inserted. The number of fluoroscopic images was decreased by 85% and the number of passes required to place the guide wire in acceptable position was decreased by 60% using computer enhanced technique.
A fluoroscopic based computer enhancement system was designed for accurate insertion of guide wires for hip fracture fixation while decreasing fluoroscopy time.
The number of fluoroscopic images and passes required to place the guide wire in acceptable position were decreased using computer enhanced technique. Final guide wire position was not different between the two groups.
Orthopedic surgeons are exposed to radiation from fluoroscopy on a daily basis. This system allowed us to insert guide wires using substantially less fluoroscopy, without compromising accuracy.
An average of 13.5 images were taken for each standard technique trial compared to two images for each computer enhanced trial, representing a reduction in fluoroscopy of 85%. One pass was used for each computer enhanced trial. An average of 2.4 trials was used for standard technique. Average final error was 3.6mm using standard technique and 3.8mm using computer technique.
A saw bone model with a soft tissue sleeve was created. A DRB (dynamic referencing body) was fixed to the femur. The DRB, fluoroscopy drum, and drill were tracked with an optical tracking device. The system created a 3D model from two orthogonal fluoroscopic images. Guide wire position was then planned on the computer model. Using a tracked drill the guide wire was inserted.
Computer enhanced trials were compared to standard techniques in regards to number of fluoroscopic images taken, number of trials to obtain acceptable guide wire position, and accuracy of guide wire placement. Guide wire position was measured on AP and lateral x-rays.
Funding: This project was funded in part through a grant from the Canadian Foundation for Innovation
Correspondence should be addressed to Cynthia Vezina, Communications Manager, COA, 4150-360 Ste. Catherine St. West, Westmount, QC H3Z 2Y5, Canada
