Orthopaedic surgeons, like many physicians who perform surgery, often rely on imaging to understand a case prior to entering the operating room. Images such as X-rays however only create a two-dimensional snapshot that often leaves much to interpretation and do not accurately or vividly depict the surface areas of bone.
In a recent Yale Department of Surgery Grand Rounds, Orthopaedics Chair Lisa Lattanza, MD, discussed how 3D imaging has enabled surgeons to become much more well-prepared before even entering the operating room. Thanks to virtual reality manipulation technology that 3D imaging offers, surgeons are able to plan a surgery using guides and jigs, which are later used during surgery to provide the surgeon with a precise cutting path or accurate drill angles. In many cases orthopaedic surgeons evaluate several different scenarios long before making an incision.
Improvements in imaging have been decades in development. Using this technology, Lattanza, is able to detect indicators for complex deformities after trauma or congenital deformities in the upper extremities. Bilateral 3D renderings are generated from scans that reveal the patient’s skeletal anatomy. Those mirrored images are laid on top on one another, which allow Lattanza to directly compare and evaluate bone topography and deformity in three planes and allow for exact correction back to normal as well as better identify locations for drill guides, cuts, and screws that may be needed.
“This type of technology allows me to perform types of operations I would otherwise be unable to perform or at least could not perform with as much accuracy,” Lattanza said.
For example, cubitus varus is a deformity that occurs after common elbow fractures in children or adults (supracondylar) where the forearm is angled too close to the body because of improper healing of the fracture. Correction is done with an osteotomy, where the bone is cut and put back in the correct position. However, X-rays and common types of osteotomies only allow surgeons to see and correct deformity in one-to-two planes and, these deformities are often times multi-planar.
“I like to compare the generic term cubitus varus to the generic term pasta,” Lattanza said. We know what pasta is but is it spaghetti, penne, or fusilli? It matters just like it matters knowing how many planes of deformity make up the cubitus varus if we are going to accurately restore the anatomy.” It is a tremendous benefit to physicians to know precisely what they are dealing with beforehand so that they can plan which of the various permutations of the procedure is most appropriate.
The clarity of the imaging technology also allows orthopaedic surgeons like Lattanza to accurately identify various conditions by categorizing into types and subsets, which then allows for a much more accurate surgical intervention. Using this imaging technology, the surgery is preplanned to implement the model that has proven to show the best possible functional outcome.
During the presentation, Lattanza referenced a case where she performed the first ever elbow transplant and spoke to how 3D imaging, developing a comprehensive team, and in this instance, rehearsing this operation with the team on a cadaver, all helped prepare them for success.
Sharing her experience, Lattanza recommended that surgeons plan carefully but remain flexible in the operating room as not everything will always go according to plan. She observed a decrease in operating time resulting from virtual planning with models and jigs through the use of 3D imaging. Although this technology is a critical tool, she added that it comes with a learning curve in the planning process. That process, which entails working in conjunction with an imaging team and engineers, is a delicate balance between computer modeling and a comprehensive understanding of both biomechanics and anatomical function.
“3D will likely become the standard of care and less expensive in the future,” Lattanza added. “The future is bright and we are looking forward to the next steps in technology where augmented reality and 4D printing of bone and cartilage become a reality in the near future.”