Mechanical nociception protocol
Electric Von Frey Protocol
Practical workflow for measuring rodent mechanical withdrawal threshold with an electronic von Frey aesthesiometer. Built for mechanical allodynia, inflammatory pain, neuropathic pain, and analgesic efficacy studies.
Use this protocol when
- Mechanical withdrawal threshold is the primary pain endpoint.
- You need direct force values in grams instead of filament sequence scoring.
- You are running longitudinal pain testing before and after injury, treatment, or recovery.
- You need explicit response criteria, exclusion rules, and confound controls.
Primary endpoint
Withdrawal force, g
Species
Mouse or rat
Trials
3-5 per paw
Main risk
Ambiguous movement
Protocol Steps
Prepare the apparatus
Place animals in individual clear chambers on an elevated mesh platform. Verify the electronic von Frey probe is calibrated, clean, and zeroed before testing.
Acclimate animals
Allow 30-60 minutes on the mesh platform before testing. Begin only when exploratory movement, grooming, rearing, and chamber-directed escape behavior are minimal.
Apply the probe
Contact the mid-plantar hind paw perpendicular to the surface. Avoid toes, pad edges, inflamed wounds, sutures, or areas where probe placement cannot be repeated consistently.
Ramp force smoothly
Increase force steadily until a brisk withdrawal, licking, shaking, or clear escape response occurs. Do not tap, jab, or accelerate suddenly.
Record valid trials
Collect 3-5 valid trials per paw with at least 60 seconds between applications. Alternate paws when bilateral testing is planned.
Summarize threshold
Report trial-level force values and the median threshold per paw, subject, group, and timepoint. Compare against baseline and contralateral controls when appropriate.
Operating Parameters
| Parameter | Default | Why it matters |
|---|---|---|
| Habituation | 30-60 min | Extend if animals remain highly active or grooming. |
| Trials per paw | 3-5 valid trials | Exclude ambiguous movement before calculating threshold. |
| Inter-trial interval | At least 60 s | Reduces sensitization and response carryover. |
| Probe site | Mid-plantar hind paw | Keep placement consistent across animals and timepoints. |
| Endpoint | Withdrawal force in grams | Use median threshold when outliers are likely. |
Score as positive
- Brisk paw withdrawal
- Withdrawal followed by licking or shaking
- Clear escape response tied to probe pressure
Exclude or repeat
- Grooming before probe contact
- Weight shift without withdrawal
- Climbing, rearing, or chamber movement
- Probe slip or contact with toes/pad edge
- Startle from experimenter or cage disturbance
Methods Text
Mechanical withdrawal thresholds were measured using an electronic von Frey aesthesiometer. Animals were acclimated in individual chambers on an elevated mesh platform before testing. The probe was applied perpendicular to the mid-plantar hind paw with a steady force ramp until a brisk withdrawal, licking, shaking, or clear escape response occurred. Three to five valid trials were collected per paw with at least 60 seconds between applications. Ambiguous movements, grooming, chamber disturbance, probe slip, or non-plantar contact were excluded. Thresholds were summarized as the median withdrawal force in grams for each paw, subject, group, and timepoint.
Evidence
Verification and citation records
The protocol is paired with product verification, the ConductScience citation registry, and peer-reviewed methods references.
ConductScience verification
Product evidence, storefront checks, and verification context live in the ConductScience verification area.
https://conductscience.com/verifiedVon Frey registry result
Product: Von Frey Apparatus. Brand: MazeEngineers. Result: one related methods citation for electric Von Frey hyperalgesia testing.
https://conductscience.com/citations?product=von-freyhttps://conductscience.com/citationsPublished methods result from the registry
Kodali M, Madhu LN, Kolla VSV, et al. FDA-approved cannabidiol [Epidiolex] alleviates Gulf War Illness-linked cognitive and mood dysfunction, hyperalgesia, neuroinflammatory signaling, and declined neurogenesis. Military Medical Research (2024). DOI: 10.1186/s40779-024-00563-2.
The registry result identifies a published methods use of an electric Von Frey apparatus from Maze Engineers for hyperalgesia testing.
https://doi.org/10.1186/s40779-024-00563-2Citation
Cite this protocol
Version 1.0.0. Last updated 2026-05-05. Use the canonical URL below when citing this protocol in lab documentation, methods drafts, or internal study plans.
Recommended citation
ConductScience. (2026). Electric Von Frey Protocol (Version 1.0.0). ConductScience. https://conductscience.com/protocol/electric-von-frey
BibTeX
@misc{conductscience_electric_von_frey_protocol_2026,
title = {Electric Von Frey Protocol},
author = {{ConductScience}},
year = {2026},
version = {1.0.0},
url = {https://conductscience.com/protocol/electric-von-frey},
note = {Rodent mechanical withdrawal threshold protocol}
}Literature
References behind the workflow
These papers support the measurement logic, the electronic force-readout approach, and the broader use of mechanical withdrawal thresholds in rodent pain studies.
Assessing mechanical allodynia in the rat paw with a new electronic algometer
Angeby Moller K, Johansson B, Berge OG. Journal of Neuroscience Methods (1998). DOI: 10.1016/S0165-0270(98)00083-1.
Directly relevant to electronic force measurement in rats. The paper describes a hand-held electronic pressure algometer and pressure-induced withdrawal thresholds after neuropathy.
https://doi.org/10.1016/S0165-0270(98)00083-1An electronic pressure-meter nociception paw test for mice
Cunha TM, Verri WA Jr, Vivancos GG, et al.. Brazilian Journal of Medical and Biological Research (2004). DOI: 10.1590/s0100-879x2004000300018.
Validates an electronic mechanical paw test in mice and supports direct force readouts for inflammatory nociception studies.
https://doi.org/10.1590/s0100-879x2004000300018Quantitative assessment of tactile allodynia in the rat paw
Chaplan SR, Bach FW, Pogrel JW, Chung JM, Yaksh TL. Journal of Neuroscience Methods (1994). DOI: 10.1016/0165-0270(94)90144-9.
Foundational rodent von Frey threshold paper. It documents stimulus-response threshold estimation and reproducibility considerations for neuropathic pain testing.
https://doi.org/10.1016/0165-0270(94)90144-9A Simplified Up-Down Method (SUDO) for Measuring Mechanical Nociception in Rodents Using von Frey Filaments
Bonin RP, Bories C, De Koninck Y. Molecular Pain (2014). DOI: 10.1186/1744-8069-10-26.
Useful when a study uses filament-style von Frey scoring or needs a comparator method for threshold estimation.
https://doi.org/10.1186/1744-8069-10-26Methods Used to Evaluate Pain Behaviors in Rodents
Deuis JR, Dvorakova LS, Vetter I. Frontiers in Molecular Neuroscience (2017). DOI: 10.3389/fnmol.2017.00284.
Review-level context for mechanical, heat, cold, and spontaneous pain behavior assays, including electronic von Frey systems.
https://doi.org/10.3389/fnmol.2017.00284
Related product
Electric Von Frey
Use the Electric Von Frey product page for product specifications, ordering, quote requests, and configuration details. This protocol defines the experimental workflow for labs planning mechanical pain threshold testing.
https://conductscience.com/lab/electric-von-frey/