Clinic foot screening guide: plantar thermal protocol

The seven zones

Each foot is divided into seven zones: on the sole, the great toe (hallux), the metatarsal head region (ball of foot), the central forefoot (metatarsal shaft region), the fifth metatarsal head, the midfoot and the heel; plus the dorsal midfoot on the top of the foot, where Charcot (neuropathic) arthropathy typically shows first. PodiaScan records temperature in each zone and compares the matching zone on the opposite foot.

Screening workflow

1. Explain the procedure and confirm the patient has no open wounds.
2. Ask the patient to rest seated for 10–15 minutes before measuring.
3. Record each zone with a handheld infrared thermometer, holding the sensor 1–2 cm from the skin.
4. Enter or sync readings into PodiaScan in the same order each time.
5. Review the contralateral delta for each zone automatically.
6. Document any hotspots, visual findings and action taken.

Interpreting the delta

• Below 1.5 °C: normal variation. Continue routine review.
• 1.5 °C to 2.1 °C: warning zone. Increase monitoring, consider footwear and activity review, and recheck within 24–48 hours.
• 2.2 °C or above: high-inflammation alert. Examine the foot closely, off-load pressure, and refer or escalate according to clinic protocol.

Caveat: contralateral comparison assumes one foot is unaffected. In bilateral disease, previous amputation or absent contralateral limb, a normal delta can be falsely reassuring; an ascending toe-to-knee gradient has been suggested as an alternative. Temperature alone can neither confirm nor exclude active Charcot arthropathy, and no dorsal-specific threshold has been validated. Evidence and references.

Documentation and follow-up

PodiaScan stores every session, calculates a 90-day trend, and exports a PDF report with the temperature grid, deltas and summary status. Use these reports for MDT meetings, patient education and audit.