Figure 3. Percentage difference between clinical measures and 3D scans of the foot, ankle and lower leg. The 3D scanners are: Artec Eva (Eva), Structure Sensor I (SSI), Structure Sensor II (SSIl), Sense, Spectra, and Trnio applications for iPhone 11 (Trnio 11) and iPhone 12 (Trnio12). Positive differences in the y-axis show that the 3D scan was larger in size than the clinical measurement. Dotted line represents 5% difference.
*Trnio has since retired the apps used here.
Reprinted from Farhan M, Wang JZ, Lillia J, Cheng TL, Burns J. Comparison of multiple 3D scanners to capture foot, ankle, and lower leg morphology. Prosthet Orthot Int. 2023;47(6):625-632. doi: 10.1097/PXR.0000000000000230. Use is per Creative Commons License CC BY.
By Robert Weil, DPM
Prescription orthotics have always been a crucial part of my sports podiatry practice. Athletes of all sports, levels, and ages expect comfort and positive results with their foot, ankle, knee, and postural problems from using their orthotics. Let’s also include enhanced performance among those benefits. However, preciseness and accuracy of the prescription along with manufacturing turnaround time are key! My figure skating specialty with boot-fitting demands and alignment criteria are good examples.
An exciting innovation advance to the orthotics world with the new smartphone 3D technology was introduced to me by orthotics consultants at Henhat’s lab and my long time “orthotics guru” lab manager Darrin Harpham. I have forever used neutral position plaster casting with FAB results from superstars to kids and grandmas and was a very tough sell for any scan alternatives (Figure 3), let alone scans with my iPhone! Even with the time-consuming and messy casting always included, as well as turnaround time challenges, I was always stubborn and reluctant to depend on any of the available alternatives. Darrin also initially felt the same cautious reluctance. Well, my how times have changed!
Orthotics and foot scanning has been available for some time at walking and running shoe stores and with some podiatrists and physical therapists, but I always questioned their accuracy and results. Too many patient complaints and necessary orthotics adjustments were needed. I was pleasantly surprised with not only my personal positive consistently great results with patients and athletes over this past year, but also with lab feedback from other podiatrists and doctors with the new iPhone 3D phone scanning. Big step up!
With some easy and proper instructions for technique and methods provided by the lab, podiatrists can really take advantage of this progressive innovation for themselves and their patients.
Robert A. Wei, DPM,l is a sports podiatrist in private practice in Lisle, Illinois. He hosts “The Sports Doctor,” a live weekly radio show on bbsradio.com, or you can visit his website, thesportsdoctorradio.com. His book, #HeySportsParents written with Sharkie Zartman, is available on Amazon.com. Dr. Weil was inducted into the prestigious National Fitness Hall of Fame in April 2019. Find him at thesportsdoctorradio.com.
