Digital Scanning Guidelines

Scanning Methods

When sending your scans, please tell us which scanning method you used:

Scan the outside of the cast:
Measure the cast thickness at the forefoot, instep, and leg. Send these measurements to us with your scan.

Scan the plaster positive mold

Direct scan of patient:
Be sure they are sitting reasonably still and the scan captures their best corrected foot and ankle position as much as possible.

Accepted File Formats

.stl (recommended)
.obj
.ply
(Please convert your file to one of these file types before sending.)

File sizes between 1MB and 25MB.
When saving the scan file, ensure the units are in millimeters.

Try to keep your scan file to a reasonable size to ensure smooth transmission (apx. 10MB).

Benefits of Digital Scanning

Eliminates transportation time to Cascade Dafo

No cost for shipping casts to Cascade Dafo

Same excellent Cascade quality and Full (90-Day) Warranty

Available order status from your e-Order Dashboard

Potential Physical Models

• Outside of fiberglass cast
• Plaster positive mold
• Patient foot/leg

Accepted File Format

Please convert your file to one of these types before sending.

• .stl
• .obj
• .ply

File sizes between 1-25MB.

Save the scan file in millimeters to ensure it imports to proper scale.

Scanning Resources

For detailed techniques, take our free ABC-approved online course — Casting and Scanning for DAFOs — on the Cascade Dafo Institute.

For how-to videos, visit our YouTube Playlist on Scanning the outside of the cast.

Scanning Equipment

• The scanner you are using should have a tolerance level of +/-2mm, usually found in scanners using white light or laser technology.
• Follow the manufacturer's recommendations for setup, use, care, and maintenance, including regular calibration.
• The best resource for information about scanning equipment is directly from the manufacturer for this rapidly evolving technology.
• Please note: The infrared iPad scanners currently on the market do not meet our criteria for an incoming scan tolerance of +/-2mm when used at the distance required for scanning AFOs.

How to send us your files

Enter the order details directly into our e-Orders system and upload your digital scan files to: orders.cascade.com

You can add photos or videos, too!

Support

If you have any questions, contact:
Customer Support
CustomerSupport@dafo.com
800.848.7332 | fax: 877.856.2160
intl: +1 360 543 9306

Outside of fiberglass cast:

• 2" or 3" white fiberglass wrap
• Wrap 2-3 layers of wrap - less than 4mm thick
• Close cut seam
• Trim loose wrap
• Use calipers to measure cast thickness. See "How to Measure Cast Thickness" video

Plaster positive mold:

• Secure physical model to strong anchor point
• Remove fiberglass remnants

Direct scan of patient:

• Patient needs to be able to sit still
• Foot and ankle maintain intended position of function without manipulation
• Plexiglass surface recommended to simulate weight bearing and capture intended brace angles
• Evaluate scan while patient is still present to rescan if needed

Phone:

• Recommend iPhone 11 or newer
• Comb Scanning App
• Using a rig to scan

Handheld:

• White light scanner
• Using a rig to scan

Advantages:

• Freedom of movement - no wires from device to computer
• Provides online live training
• Scans unaffected by:
  • Lighting
  • Cast Color
  • Tape
  • Staples

Disadvantages:

• No built in CAD software
• Requires use of web portal to access scans

Advantages:

• White light scanner has years of use in the industry
• Supplied with CAS software included

Disadvantages:

• Limited mobility - wired connection to computer
• High intitial price point
• Typically additional cost per scan
• Can affect scan:
  • Over-lighting
  • Dark color cast
  • Dark color tape

Tips to resolve:

• Could be an isolated issue that can be resolved with a rescan.
• Follow scanner manufacturer guidelines for troubleshooting and calibration process.

Able to correct:

• Minimal missing data
• Limited guesswork of phyiscal model
• All anatomical features are fully represented

Unable to correct:

• Large area(s) of missing data
• Not able to recognize anatomical features

Tips to resolve:

• Adjust angle of rig to allow scanner to fully capture all planes of physical model and then rescan
• Utilize "Watertight," "Make Solid," "Solidify," or similar feature within scanning/CAD software.

Able to correct:

• When extra data can be trimmed without losing or altering the intended physical model.

Unable to correct:

• When an object and the physical model are scanned together and inseparable without creating a large unusable hole.

Tips to resolve:

• Remove unneeded remnants of loose fiberglass from cast or plaster positive mold and rescan
• Clear scanning area of everything except the scanning rig and physical model
• Prior to finalizing, identify unneeded scan data and trim:
  • Aspects of scanning rig (if scanning cast/plaster positive)
  • Frame of plexiglass plate (if scanning patient directly)

Able to correct:

• A scan exported in identifiable units, inches (in) or centimeters (cm)

Unable to correct:

• A scan exported in units greater than inches, as this creates guesswork for the amount needed to enlarge the scan and could result in low resolution scan issues

Tips to resolve:

• Adjust scanning/CAD software settings to mm

Able to correct:

• When the software is able to stitch separate data points into a single digital object.

Unable to correct:

• Algorithm fails to stitch separate data points together.

Tips to resolve:

• Utilizing "Watertight," "Make Solid," "Solidify," or similar feature within scanning/CAD software

Why unable to correct:

• Drifted amount is inconsistent along scan
• Inaccurate anatomical features

Tips to resolve:

• Secure physical model to a fixed position and rescan
• While scanning, allow slow movement in transition from medial/lateral to anterior/posterior to dorsal/plantar aspects

Why unable to correct:

• File contains no usable data

Tips to resolve:

• Rescan

Why unable to correct:

• Not able to recognize anatomical features
• Volume of scan does not match volume of physical model

Tips to resolve:

• Set resolution in scanning/CAD software to a higher resolution
• Adjust export settings to allow for 1 - 25MB file size

Why unable to correct:

• Unknown volume added to open portion of scan

Tips to resolve:

• Align cast wrap, close seam with staples or tape, and then rescan

Why unable to correct:

• Unable to estimate original features of physical model
• Entire volume of scan changed due to reducing high points and increasing low points

Tips to resolve:

• Turn off automated smoothing process within the scanning/CAD software and rescan
• Do not apply smoothing tool/feature to scan

1. Cast accurately

Use a thin, even, white fiberglass wrap to cast the foot and lower leg in the patient's best position of function. Capture angles as close to the balanced position — vertical heel, level forefoot, and 3 degrees of dorsiflexion — as your patient can use in the finished brace.

2. Collect cast thickness information

Prepare

• Trim off any excess casting tape or stockinette at the toes or top; do not remove the stockinette layer from inside the cast.
• The best way to measure cast thickness is with digital calipers. We recommend the iGaging 6" Digital Electronic Outside External OD Caliper with Handle. They feature a large mouth that allows you to measure deep within the cast, and they're very accurate at measuring small thicknesses (to the 1/10 mm).
• Set the measurement format to millimeters and calibrate to zero.
• Use the hold button to preserve the measurement on the screen if desired.

Measure

• Measure right after removing the cast. It's easier to get the calipers inside the cast before it's completely hardened.
• Open the jaws and place them around the target area.
• Move the calipers around a little to get an average reading of the thickness, rather than capturing the high or low point there.

Record

• Do not round up or down; simply record the measurement to the tenth of a millimeter on your cast. You'll use these measurements later, when uploading the scans.

3. Scan the outside of the cast

• Tape the cast together using light-colored tape (yellow, red, white). Darker colors will not scan well.
• General tips for setting up your scanning zone:
  • Avoid background movement in the scanning zone.
  • Make sure the scanning zone is not too close to any walls and remove clutter form the area.
  • Follow manufacturer's directions for scanning technique, distance from camera, and the size of the scanning zone.
  • Avoid excessive particulates in the air that can be captured in the scan.
  • Avoid strong beams of light. Flat, even lighting is best.
  • To best capture all critical anatomy, you'll need to create a holder for the casts. The casts should be at a 35°-55° angle with the toes pointed up.
• Scan according to the scanning equipment manufacturer's directions.
• Save the cast so you can check the accuracy of the scan.

4. Check raw scan and resolve issues

• Large holes or holes at critical anatomy points = rescan.
• Anomalies from scan image or stitching mismatches (odd lines/bumps/missing pieces) = rescan.
• Save this raw scan file in case you need to make changes later.
• Do not smooth.
• Trim excess info included in scan (e.g., the table, bits of extraneous info).
• Simplify scan to reduce unnecessary detail to keep the exported file size within 1-25MB.

5. Export scan

• Save in millimeters to standardize with our process for accuracy.
• Export as .stl, .ply, or .obj because these are universal 3D object file types.
• Verify the file size is under 25MB. If the file is too large, go back to the saved raw scan, simplify some more, and make sure all extra information has been removed. Export the file again.

6. Final check of exported scan

• Spikes = go back to saved raw scan to clean up extra data bits causing spikes, then export again.
• Scans can look perfect on the screen, but may not be accurate. Verify the scan accuracy by comparing width measurements of the scan to actual measurements of the cast at the met head M/L, malleolar M/L, mid-tibia M/L and A/P, and overall foot length. If your software does not provide a measurement function, there are some free downloadable programs online that you may find useful. See Scanning and Software for recommendations.
• Re-scan if measurements are not accurate to within +/-2mm. Do not alter scan to match because it may keep the overall volume while adding or subtracting from other areas, resulting in a poor fit. Be sure to follow the scanner manufacturer's directions for regular calibration of your scanner.

7. Order and upload your scan

• Place your DAFO order using our e-Orders sit. You'll upload your scan files as part of the ordering process.
• If you indicate the scan is of the outside of a cast, you'll see fields to enter the cast thickness measurements. This is important! It tells us to include steps to remove the excess cast volume.