3D-printed model can be cheap, effective in surgical planning for hip condition

Utilizing a 3D model in the preoperative planning of osteoplasty for a hip impingement condition can alter the location and extent of preparation, potentially improving patient outcomes at minimal cost.

The experimental study, led by a group of four researchers from New York, was published online June 6 in the American Journal of Roentgenology.

“3D models can be an adjunct for surgical planning because they provide surgeons with more detailed observation and intuitive understanding of osseous anatomy,” wrote corresponding author Tony T. Wong, with the department of radiology at NewYork-Presbyterian Hospital at Columbia University Medical Center and colleagues. “They are perceived to be able to reduce surgical time and have a favorable impact on patient outcomes. In this study, we found that 3D models alter preoperative planning for osteoplasty in [femoroacetabular impingement] surgery.”

Wong and colleagues used data from 10 consecutive patients with a clinical diagnosis of femoroacetabular impingement who had received radiographs, CT and MRI.

A 3D model of each patient’s hip was printed to scale from the CT data. Two orthopedic surgeons performed a preoperative evaluation of each patient, and the effect of the 3D models in changing the planned surgery was then calculated.

Results showed after using the 3D model, the planned osteoplasty was changed for at least one reader in 90 percent of femurs and in 100 percent of acetabula. The proportions of these changes ranged from 20 to 55 percent at femoral positions and 35 to 75 percent at acetabular positions.

Additionally, authors noted a higher number of changes occurred in patients with alpha angles of 60 degrees or more.

“Although we cannot conclude that 3D models would lower the rates of revision surgery, our results show the potential they have for localizing candidate areas for a more aggressive osteoplasty that would not have been seen otherwise,” Wong et al. wrote.

But what's the cost?

The cost and effort that go into the postprocessing of 3D printing must be considered in these situations, the authors wrote. However, in this study, the print materials for the femur and acetabulum model amounted to a mere $3.01, and all models were completed on a relatively inexpensive desktop printer.

It took one hour of processing time to properly calibrate the 3D printer, and an additional two hours and 37 minutes to physically print the model, according to the study. While proper training is required for this process, authors see a bright future in three-dimensional printing.

“Although costlier printers have advanced capabilities, generating a model for surgical planning can be simple and affordable,” Wong et al. wrote. “As this growing technology develops, costs will inevitably decrease and efficiency will rise.”