April 24, 2002

Boise State Project Creates Human Bone and Joint Prototypes for Surgeon

The unlikely collaboration of a Boise orthopaedic surgeon and two engineering professors at Boise State has provided a much clearer meaning to the term “anatomically correct.”

While it would seem that Dr. Kevin Shea’s medical practice and the rapid prototype technology employed by mechanical engineering professors Steve Tennyson and Joe Guarino would not have much in common, the trio, along with other colleagues from the university, has developed a cutting-edge process to provide surgeons such as Shea with anatomically precise solid models of knees, hips, spines and other body parts on which they are to operate.

Using specialized imaging software to create virtual graphic models from CT (computerized tomography) and MRI (magnetic resonance imaging) scans electronically transmitted from Intermountain Medical Imaging, Guarino and Tennyson are able to take those images and program them into the university’s rapid prototyping machine, which was installed in the College of Engineering a year and a half ago, and build exact physical and virtual models of bones and joints.

Unlike conventional prototype processes that would take considerably longer to make exact models, the technology used by Tennyson and Guarino can produce the models in a matter of hours. The machine is located on the fourth floor of Boise State’s Micron Engineering Center. Prototyping is a standard operation in most manufacturing processes. As new products are developed, parts and assemblies are often reproduced in clay, wood and metal to assure form, fit and function. Rapid prototyping is used to save time and cut costs at every stage of the product development process. Once the scan has been made, Intermountain Medical Imaging can transmit a file of the image to Guarino and Tennyson, who then run the computerized prototyping machine to produce the plastic-like model.

Assisted by Boise State kinesiology professor Ron Pfeiffer and BSU radiologic sciences professor Lorrie Kelley, who provide anatomical and imaging expertise, Guarino and Tennyson can quickly and efficiently furnish Shea with a prototype that replicates the body part right down to the most minute detail.

“That way,” said Pfeiffer, “surgeons like Kevin can ‘rehearse’ the surgery using the model before they actually go in. It helps the surgeons prepare, which can improve the outcome for the patient.”

Given the precision needed in the operating room — especially during surgeries to correct spinal deformities such as Shea performs — the availability of a three-dimensional model that so closely resembles the real thing is an invaluable tool.

“There are certain risks associated with spinal surgery,” said Shea, who specializes in pediatric surgery. “Having a model of the spine allows us to plan the surgery more completely and do it more safely.”

Shea, an adjunct professor in Boise State’s kinesiology department, says the union of high-speed image transmission and rapid prototyping to assist surgeons is a fairly new process that has yet to receive widespread notice in the medical community. “I’ve used the process to prepare for about six patients since last year,” he said, “and the Shriners Hospital for Children in Salt Lake City has contacted us about making models.”

Shea and his Boise State colleagues have applied for funding to continue their efforts. Given the advantages the models provide, there’s a good chance it will only be a matter of time before the practice becomes commonplace.