By Terrell S. Tate, BOCP,CO
Entering the digital world of orthotics and prosthetics begins with a decision on how to scan a patient. So we should first consider the scanning equipment. There are many choices for different applications in the world of digital scanning outside of orthotics and prosthetics. The automotive industry and the movie industry, for example, use scanning equipment that has great precision for replicating a model. But scanning a detailed model of a city street that will be enlarged on a movie screen and scanning an interior door panel are quite different.
In my experience, the same concept applies in orthotics and prosthetics. For example, the accuracy that is necessary for capturing the shape of the head in order to reliably produce a cranial molding helmet is different from the accuracy required to capture the shape of a torso for a scoliosis TLSO. Some prosthetists would argue that greater precision is necessary for scanning a transtibial limb. And I would use the same criteria to evaluate the need for accuracy. Do you tend to mostly scan directly to the skin because you have patients with challenging anatomical shapes, or are your patients always scanned over a 6mm gel liner?
After making this decision, we can consider how to capture the shape. Each scanning device has a minimum distance from the object being scanned. The recommended minimum distance for Structure Sensor (Mark II) is 11.8 inches. In my experience using this product, this was never an issue when scanning a torso–but could be challenging when scanning a transtibial limb. I got very comfortable maneuvering into awkward positions, sometimes on my back, to capture the limb with an amputee seated. Structure Sensor connects to the iPad and uses both cameras, so holding the iPad while I am doing the scan is very natural. I always carefully evaluate the quality of my scan on the screen to ensure that I have a good image without distortion. The iPad screen makes this very easy.
The Comb Scanner uses the True Depth technology in the iPhone front facing camera (model XR and higher). So scanning with the front facing camera is like taking a selfie. I transitioned to this scanner about a year ago and I had a learning curve because I honestly do not take a lot of selfies. But with a little practice, I am able to scan the lower limb without needing to move into awkward positions on the floor because the minimum distance for the Comb Scanner is 6 inches. I have found this to be very beneficial when scanning a patient in a doctor’s office or a patient’s living room.
Some practices that have transitioned fully to the digital platform have a dedicated room or space specifically for scanning. Historically, we have utilized a dedicated space for taking impressions because this was a messy process. Perhaps now we should take the same approach but make the space usable for the scanning process. In other words, should we set up a room with an elevated platform that allows the clinician to have more space between the limb and the floor? Perhaps a minor modification to your current casting room would be a great solution.
Another obvious consideration is how many scanners will be necessary within the practice? There is no simple answer, but evaluation of your current workflow and creative thinking is always the best answer. With multiple clinicians moving in multiple directions, perhaps one scanner could be used for clinicians outside of the main office and one scanner would remain as the dedicated in-office device. Another consideration could utilize the technician for scanning all of the impressions taken from multiple clinicians.
In my experience these and other questions should be considered and evaluated when making a decision to utilize digital scanning. However, I would argue that digital scanning produces repeatable, reliable shape capture that is superior in general to our traditional methods of impression taking for shape capture. So, the real question is not, should I scan, but how should I scan?
Terrell S. Tate, BOCP,CO, is founder and chief executive officer of MPower Health in Memphis, TN. Terry has been a prosthetist for more than 15 years and an orthotist for more than 25. He’ll be using this space on a regular basis to discuss all things technology related to the lower extremity. Reach him on LinkedIn for more about digital O&P technology.