What Are the Ways to Digitally Scan Feet for Orthotics?
3D foot scanning for orthotics has rapidly evolved from a niche technology into a mainstream clinical tool, with multiple hardware categories now available to podiatrists at dramatically different price points and levels of portability. Understanding the three primary categories of digital foot scanners — dedicated stand-up platforms, attachable structured-light cameras, and built-in smartphone and tablet sensors — is essential for any practitioner evaluating the transition from traditional casting to a digital workflow.
Dedicated Stand-Up Scanners represent purpose-built foot scanning hardware. Devices such as the Elinvision iQube series and the Envisic VeriScan Podiatric Scanner (VPS) are engineered specifically for capturing plantar foot morphology in a clinical setting. The iQube uses an array of up to five cameras beneath a tempered glass platform to capture a complete 3D plantar model in five to nine seconds, achieving accuracy down to 0.5 millimeters in its multi-camera configurations (Elinvision, 2025). The VeriScan utilizes red line-laser 3D imaging to generate a true-dimension digital cast in under 30 seconds (Envisic, 2024). These scanners support full weight-bearing, semi-weight-bearing, and non-weight-bearing positions, and can also digitize foam impression boxes and plaster casts. Their primary advantages are speed, hands-free operation, and consistency — the scanner’s fixed geometry eliminates the operator variability introduced by handheld devices. Their limitations are cost, size, and lack of portability for practitioners who treat patients across multiple locations.
Structured-Light Cameras such as the Structure Sensor series (now in its third generation) attaches to an iPad or operates as a standalone accessory. These devices project a pattern of infrared structured light onto the foot and use a dedicated depth camera to measure surface geometry at resolutions significantly higher than built-in tablet sensors. A 2023 study published in Prosthetics and Orthotics International evaluated seven different 3D scanners — including the Structure Sensor I, Structure Sensor Mark II, and several smartphone-based options — against clinical measurements and found that the Structure Sensor devices produced consistent results within acceptable clinical thresholds (Farhan et al., 2023). The Structure Sensor’s dedicated infrared hardware provides a denser point cloud and more reliable tracking than onboard phone sensors, particularly in the complex contours of the medial arch and heel, making it a favored choice among orthotic laboratories that prioritize scan fidelity while still requiring portability.
iPhone and iPad Scanning via TrueDepth represents the most accessible and portable tier of foot scanning technology. Apple’s TrueDepth system — present on the front-facing camera of iPhones since the iPhone X — projects over 30,000 infrared dots onto the scanned surface and measures their distortion to create a depth map, originally designed for Face ID authentication but now adapted for clinical 3D scanning through apps like Structure Capture and IOL TrueCast.
LiDAR. the rear-facing LiDAR sensor available on iPad Pro and iPhone Pro models since 2020, uses a time-of-flight method to measure distance at a resolution of 256 by 192 pixels, better suited to larger objects and room-scale scanning than close-range foot capture. Multiple orthotic scanning applications now leverage one or both of these sensors, allowing practitioners to capture a 3D foot impression using only the device in their pocket.
How Do the Digital Scanning Techniques Compare in Accuracy?
The accuracy among these three scanning categories is generally consistent across the available literature, though the clinical significance of the differences is a matter of ongoing debate.
Dedicated stand-up scanners deliver the highest precision – when used correctly. The iQube series achieves 0.5 to 1.0 millimeter accuracy depending on configuration, with extremely high repeatability due to the fixed scanner-to-foot geometry and elimination of operator hand movement (Elinvision, 2025). Because the patient simply stands on or places their foot on the glass platform, motion artifact is minimized and scan-to-scan consistency is maximized. For practices producing high volumes of orthotics, this repeatability may matter as much as raw accuracy. However, some versions of stand-up scanners may only house one camera, which can severely limit the range of foot that will be scanned. Poor foot positioning can also impact the capture of the lateral foot, medial arch, and heel. Some scanners may compensate for this with software that will “fill in” parts of the foot and make a best estimation of the missing contours, which can lead to inaccuracy.
Structured-light cameras like the Structure Sensor boast strong results. A 2023 multi-scanner comparison study found that the Structure Sensor Mark II demonstrated acceptable accuracy — within the five percent clinical threshold — for key foot landmarks when compared to plaster cast measurements (Farhan et al., 2023). A 2024 pediatric study comparing the Artec Eva (a high-cost industrial scanner) with the Structure Sensor II against plaster casting found that both scanners produced comparable accuracy for foot, ankle, and lower leg landmarks, with the Structure Sensor II achieving a mean bias of just 0.5 millimeters in a two-person scanning protocol (Farhan et al., 2024). The Structure Sensor’s advantage over smartphone sensors lies in its dedicated infrared projector, which provides a denser depth field and more reliable tracking through complex geometry. However, Structure cameras and their accompanying bracket systems can be pricy, and many users have reported that models (especially the Structure II) have concerning battery life or calibration issues.
iPhone and iPad scanning via TrueDepth has been studied extensively and shown to be competitively accurate with other scanning techiniques. Vogt et al. (2021) compared the iPad Pro’s TrueDepth capabilities against the industrial Artec Space Spider scanner and found that TrueDepth provided competitive accuracy, albeit with a slightly higher deviation depending on Apple model if not properly calibrated by its application software.
LiDAR however, is constrained by its lower resolution and one-meter minimum distance and was the least precise option for close-range scanning. Its 256 by 192 pixel resolution and minimum distance requirement make it fundamentally less suited to the close-range, high-detail demands of foot scanning than TrueDepth’s 640 by 480 resolution and 15-centimeter minimum range (Structure.io, 2025).
Despite these differences, all three of the first three categories capture foot length and forefoot width with high reliability. The parameter that shows the most variability across all scanning methods — including plaster casting — is arch height, due to the inherent flexibility of the midfoot and the difficulty of maintaining a consistent foot position during capture (Farhan et al., 2021).
How Does Digital Scanning Compare to Traditional Plaster Casting?
The comparison between digital scanning and plaster casting has been evaluated in multiple peer-reviewed studies, and the evidence suggests that well-executed 3D scanning produces clinically comparable results to the traditional gold standard — with advantages in speed, cost, and workflow efficiency.
A 2021 systematic review published in the Journal of Foot and Ankle Research (Farhan et al.) analyzed six studies comparing 3D scanning to traditional capture methods including plaster casting, foam impression boxes, and clinical assessment. The review found that 3D scanning was consistently faster — two to eleven minutes versus eleven to sixteen minutes for plaster casting — and that accuracy and reliability between methods were variable but generally comparable for most foot parameters. The review concluded that the quality and quantity of comparative literature remained low, but that 3D scanning showed promise as a clinically viable alternative.
Lee and Wang (2014), in a study published in the Journal of Foot and Ankle Research, compared 3D scanning directly against conventional measurement methods for capturing foot dimensions used in orthotic fabrication. Their findings indicated that the 3D scanning method produced more precise and reproducible measurements, leading the authors to recommend digital scanning over plaster casting for collecting foot measurements.
A key nuance in this comparison is that accuracy depends as much on technique as on technology. A 2024 randomized controlled trial noted that laser 3D scanning did not improve the quality or speed of ankle-foot orthosis delivery compared to plaster casting when the scanned group required more remakes and rescans — suggesting that operator proficiency with the scanning protocol is a critical variable (Roberts et al., referenced in Farhan et al., 2024). Plaster casting, for all its messiness and time cost, provides the practitioner with direct tactile feedback: the clinician physically holds the subtalar joint in neutral, locks the midtarsal joint, and dorsiflexes the fifth metatarsal head to load the lateral column — all through hand contact with the foot. This proprioceptive control is difficult to replicate when the clinician must simultaneously hold the foot and manipulate a handheld scanner, which is why two-person scanning protocols consistently outperform single-person protocols in accuracy studies.
From a cost perspective, plaster casting materials range from approximately 28 to 50 dollars per impression, while a 3D scan costs between 3 and 10 dollars on average when amortized over device lifespan (Payne, 2007; KevinRoot Medical, 2023). The digital file also eliminates shipping costs and transit damage risk, and allows for indefinite storage, easy modification, and instant reorder without recasting.
The emerging consensus in the podiatric literature is that 3D scanning — across all three technology tiers — is a clinically acceptable alternative to plaster casting for orthotic fabrication, provided the clinician maintains proper foot positioning during the scan. The technology is faster, less costly, and more efficient, but its accuracy is ultimately constrained by the same variable that determines plaster cast quality: the practitioner’s ability to capture the foot in a corrected, neutral position.
References
Farhan, M., Wang, J.Z., Bray, P., et al. (2021). Comparison of 3D scanning versus traditional methods of capturing foot and ankle morphology for the fabrication of orthoses: a systematic review. Journal of Foot and Ankle Research, 14(2).
Farhan, M., et al. (2023). Comparison of multiple 3D scanners to capture foot, ankle, and lower leg morphology. Prosthetics and Orthotics International, 47(6), 625–632.
Farhan, M., et al. (2024). Comparison of accuracy and speed between plaster casting, high-cost and low-cost 3D scanners to capture foot, ankle and lower leg morphology of children requiring ankle-foot orthoses. Journal of Prosthetics and Orthotics.
Lee, Y.C., Lin, G., & Wang, M.J. (2014). Comparing 3D foot scanning with conventional measurement methods. Journal of Foot and Ankle Research, 7(1), 44.
Payne, C.B. (2007). Cost benefit comparison of plaster casts and optical scans of the foot for the manufacture of foot orthoses. Australasian Journal of Podiatric Medicine, 41(2), 29–31.
Vogt, M., Rips, A., & Emmelmann, C. (2021). Comparison of iPad Pro’s LiDAR and TrueDepth capabilities with an industrial 3D scanning solution. Technologies, 9(25).
Structure.io. (2025). Foot landmark detection with Structure. 3DBODY.TECH Journal — International Journal of 3D Body Technologies, Vol. 2.