The Ankle Inversion Test measures how far the foot and ankle move inward. It can be used to track ankle mobility, compare sides and add context to ankle movement, balance and lower-limb testing.
A client may report that one ankle feels stiff when turning the sole inward, or they may show different movement control between sides after a period of reduced ankle loading. The Ankle Inversion Test provides a repeatable way to record inward ankle movement and monitor change.
This test is useful for establishing baseline ankle range of motion, comparing left and right sides, and adding context to related ankle strength, balance, hop and lower-limb movement assessments. It should not be interpreted as a complete measure of ankle function on its own.
Test name: Ankle Inversion Test
Purpose: Assess ankle inversion range of motion
What it assesses: The ability to move the sole of the foot inward
Equipment: Measurz inclinometer or equivalent inclinometer
Key finding: Inversion angle in degrees
Best used with: Ankle eversion, dorsiflexion, plantarflexion, balance, hop testing and ankle strength measures
Key limitation: It measures ROM, not ankle control, strength or stability on its own.
The Ankle Inversion Test measures movement of the foot and ankle into inversion. Inversion is the movement where the sole of the foot turns inward toward the midline.
The result is recorded in degrees using the Measurz inclinometer or an equivalent inclinometer. Because inversion can be influenced by subtalar motion, midfoot movement and whole-leg rotation, the test position, stabilisation and device placement need to be consistent.
The Ankle Inversion Test is used to:
Establish baseline ankle inversion ROM.
Compare left and right sides.
Monitor change over time.
Add context to ankle strength testing.
Support balance and hop test interpretation.
Track progress after periods of reduced loading.
Identify whether further ankle mobility or control testing may be useful.
It is most useful when interpreted alongside symptoms, ankle eversion, dorsiflexion, plantarflexion, balance, strength and functional movement findings.
The test measures ankle inversion ROM in degrees.
It does not directly measure:
Ankle strength.
Balance.
Proprioception.
Pain source.
Lateral movement quality.
Ligament integrity.
Overall ankle function.
Return-to-sport readiness.
A reduced inversion score may indicate less inward ankle movement under the test condition, but it does not explain the cause by itself.
Ankle inversion may be measured actively or passively.
Active inversion means the client moves the foot inward using their own effort.
Passive inversion means the professional guides the foot inward while the client remains relaxed.
Both methods can be useful, but they should not be mixed without clear recording. Active ROM may be affected by strength, motor control, pain or confidence. Passive ROM may provide more information about available assisted range.
When retesting, use the same method each time.
This test may be useful for:
Runners.
Field sport athletes.
Court sport athletes.
Dancers.
Gym clients.
Ankle mobility clients.
Lower-limb progress tracking.
Clients where side-to-side ankle ROM comparison is useful.
Use caution when the client has acute ankle pain, high irritability, recent injury, swelling, neurological symptoms or pain that meaningfully limits movement.
Measurz inclinometer or equivalent inclinometer.
Table or mat.
Measurz app.
Notes for side, active/passive method, symptoms and compensation.
Ask the client to remove shoes and socks. Position the client so the lower leg can remain stable while the foot moves into inversion.
The client may be positioned lying down or seated depending on your chosen protocol. Whichever position is used, record it and repeat the same position at retest.
Stabilise the lower leg to limit whole-leg rotation. The goal is to measure ankle and foot inversion rather than hip or tibial movement.
Open the Measurz inclinometer or equivalent device. Place the inclinometer consistently according to the chosen protocol.
Ask the client to move the foot inward as far as comfortable and controlled.
Use a consistent instruction such as:
“Turn the sole of your foot inward as far as you comfortably can without rotating the whole leg.”
At the end of the movement, pause and record the inversion angle in degrees.
If testing passively, guide the foot gently into inversion while keeping the lower leg stable. Record that the test was performed passively.
Repeat the same method on the other ankle if side comparison is needed.
Ask the client what they feel and where they feel it. Record pain, tightness, blocking, stretch, apprehension or instability sensations. Stop if symptoms meaningfully alter movement quality.
Record inversion ROM in degrees.
Compare:
Left versus right side.
Active versus passive ROM, if both are tested.
Baseline versus retest.
Inversion versus eversion.
ROM findings with symptoms.
ROM findings with strength, balance and hop testing.
A lower value may indicate reduced inversion movement under the tested method, but it does not explain the reason on its own. A higher value is not automatically better, especially if the client reports apprehension, pain, poor control or a history of recurrent ankle sprains.
Stronger interpretation depends on symptoms, side comparison, eversion ROM, dorsiflexion ROM, plantarflexion ROM, strength, balance and functional findings.
Evidence level: Level 2 — closest available published reference values.
Exact norms for this specific Measurz inclinometer setup are limited, but peer-reviewed ankle motion data gives useful context. A normative study of 100 healthy adults aged 19–25 years reported ankle inversion rotation of:
Men: 20.5° ± 6.3°
Women: 25.5° ± 6.2°
Dominant ankle: 22.2° ± 6.8°
Non-dominant ankle: 23.9° ± 6.6°
These values were measured with an ankle arthrometer, not the Measurz inclinometer, so use them as contextual benchmarks, not strict pass/fail cut-offs.
For practical Measurz interpretation, ankle inversion around 20–25° may be a reasonable reference range for many healthy young adults. Interpret results with side-to-side comparison, baseline change, active/passive method, symptoms, eversion ROM, strength, balance and hop test findings.
Avoid using one universal number as a pass/fail rule. A lower value may still be acceptable if both sides are similar and symptoms are absent, while a higher value may still need context if pain, apprehension or poor control is present.
A 2025 systematic review of lower-limb ROM measurement reported wide variability in reliability across goniometry, photogrammetry and smartphone methods. This reinforces that protocol consistency is important when measuring ankle ROM.
Kiatkulanusorn et al. reported that common clinical goniometric devices can vary in concurrent validity and reliability. For ankle inversion specifically, consistency in stabilisation and device placement is critical because foot, subtalar and whole-leg movement can influence the score.
No universal MDC or MCID should be assumed for this exact Measurz ankle inversion protocol unless the same protocol, device, population and testing method are used.
Common errors include:
Rotating the whole leg instead of moving the foot and ankle.
Measuring toe movement rather than rearfoot/ankle movement.
Inconsistent device placement.
Failing to stabilise the lower leg.
Failing to record symptoms.
Confusing active and passive ROM.
Comparing different test positions directly.
Assuming the ROM score reflects strength or control.
Over-interpreting side differences without symptoms or functional context.
Limitations include:
Inversion can come from multiple foot and ankle regions.
Device placement can change the score.
Passive and active ROM may differ.
A larger ROM is not always better.
ROM does not equal stability, strength or control.
Exact norms are limited for many field protocols.
Use the test for:
Ankle ROM baseline.
Side-to-side comparison.
Progress tracking.
Ankle mobility programming.
Supporting lower-limb movement assessment.
Adding context to balance and hop testing.
Deciding whether ankle strength or control testing would add useful information.
For example, a client with reduced inversion ROM, discomfort during side hopping and reduced ankle eversion strength may need a different interpretation than a client with reduced inversion ROM but no symptoms, strong balance scores and normal function.
Record:
Test name: Ankle Inversion Test.
Side tested: left or right.
Score: inversion ROM in degrees.
Method: active or passive.
Position: lying, seated or the specific position used.
Device: Measurz inclinometer or equivalent inclinometer.
Landmarks/device placement: record the placement used.
Pain score: 0–10.
Symptom location: lateral ankle, medial ankle, foot, Achilles, calf or other.
Symptom quality: stretch, pinch, block, pain, apprehension or instability.
Compensations: whole-leg rotation, toe movement, hip movement or poor control.
Comparison side: opposite ankle.
Related findings: eversion ROM, dorsiflexion ROM, plantarflexion ROM, ankle strength, balance and hop testing.
Progress comments: whether range improved, symptoms changed or side-to-side difference reduced.
Retest date: for monitoring change.
This helps make the result repeatable, easier to interpret and more useful for progress tracking.
Ankle Eversion Test
Ankle Dorsiflexion Test
Ankle Plantarflexion Test
Weight-Bearing Lunge Test
Y-Balance Test
Single-Leg Balance
Side Hop Test
Ankle Inversion Strength Test
Ankle Eversion Strength Test
It measures how far the foot and ankle move inward, with the result recorded in degrees.
Either can be useful. Active testing records the range the client can achieve themselves. Passive testing records the range achieved with assistance. Record the method and repeat it consistently.
It provides movement comparison information, but it does not explain the cause on its own. Interpret it alongside symptoms, strength, balance and functional findings.
Not always. A larger range may be useful in some contexts, but if it is associated with apprehension, pain or poor control, it should be interpreted cautiously.
Use the same position, same device placement, same active/passive method and compare both sides over repeated sessions.
The Ankle Inversion Test measures inward ankle ROM.
Stabilisation and device placement matter.
Record whether testing is active or passive.
Use side comparison and baseline tracking.
Do not interpret ROM as strength, control or stability.
Canever, J. B., Nonnenmacher, C. H., & Lima, K. M. M. (2025). Reliability of range of motion measurements obtained by goniometry, photogrammetry and smartphone applications in lower limb: A systematic review. Journal of Bodywork and Movement Therapies. Advance online publication. https://doi.org/10.1016/j.jbmt.2025.01.009
Kiatkulanusorn, S., Luangpon, N., Srijunto, W., Watechagit, S., Pitchayadejanant, K., Kuharat, S., Anwar Bég, O., & Paepetch Suato, B. (2023). Analysis of the concurrent validity and reliability of five common clinical goniometric devices. Scientific Reports, 13, 20915. https://doi.org/10.1038/s41598-023-48344-6
