REFERENCE · DIAGNOSTIC TECHNIQUE

Sign-Based Gait Comparison

Clinician-focused educational reference; assessment requires appropriate expertise and a safe clinical setting.

Purpose and Suitability
Anatomy and Physiology
Preparation and Safety
Performing the Assessment
Interpreting Findings
Explaining the Result
Evidence and Limitations
Media and Accessibility
Research and Sources

Purpose and Suitability

This assessment compares walking under selected conditions to ask whether a positive functional pattern is present. It is useful when the person can safely undertake a meaningful comparison; it is not suitable as a compulsory series of challenges for someone who cannot stand or walk safely.

Gait: The pattern of walking. Sign-based assessment: Using observed clinical findings to support a diagnosis, rather than relying on appearance or normal investigations alone.

The clinician should specify the question: for example, whether observed knee yielding fits the strength and balance demonstrated in other safe activities. The inventory describes the range of possible observations. [1]

Anatomy and Physiology

Walking combines leg strength and joint movement with balance, sensory feedback and planning. The spinal cord and brainstem contribute to stepping and postural control; cortical, basal-ganglia and cerebellar networks help select, adapt and coordinate movement. Vision, inner-ear signals and sensation from the limbs supply information about the body and surroundings.

Proprioception: The sense of where body parts are and how they are moving.

Changing direction, attention, rhythm or support changes the demands of the task. A comparison can reveal a pattern worth explaining, but cannot identify one brain-network mechanism in an individual. The clinical question remains whether that pattern fits a functional disorder, another condition, or both. [1]

Preparation and Safety

Explain the purpose before asking for unfamiliar movements. Agree consent, a stop signal, breaks and any touch or guarding. Ask about falls, injuries, pain, dizziness, fatigue, footwear and communication needs. Check the space, usual aid and available assistance before starting.

A trained clinician must judge which tasks are safe. Stop for loss of support, near-fall, new symptoms, pain or the person’s request. Do not introduce running, eye closure or a balance challenge simply because it appears in an inventory. A task omitted for safety is untested, not negative. These practical safeguards are part of this teaching outline, not diagnostic criteria.

Performing the Assessment

Obtain the history and complete a neurological, vestibular and musculoskeletal assessment appropriate to the presentation before interpreting gait variation.
Prepare a clear walkway with a trained spotter, gait belt when indicated, and the person’s usual aid. Do not remove an aid merely to make the sign more visible.
Record comfortable forward walking first. Note base, step length, rhythm, knee control, foot placement, trunk movement, arm swing and recovery from imbalance.
Select only safe comparison tasks relevant to the observed pattern. These may include a change in speed, backward walking, tandem walking, rhythmic cueing, a dual task or—in a person for whom it is genuinely safe—brief running.
Look for a reproducible change that is internally inconsistent with the baseline pattern or incongruent with recognized neurological gait disorders. An improvement during a more demanding task may be especially informative, but is not universal.
Consider fear of falling, pain, fatigue, footwear, environment, medication and coexisting disease. An unusual or dramatic gait is not automatically functional.
Explain any positive sign collaboratively and, where useful, connect the improved condition to physiotherapy rather than treating it only as a diagnostic observation.

This is the original source-based outline, not an independently validated seven-item test. [1]

For each comparison, describe what changed and what stayed the same: speed, direction, support, surface, instructions and symptoms. A dual task means walking while also doing another activity, such as a simple conversation if suitable. Record whether both activities were actually performed; stopping one task changes the meaning of the comparison. Choose a task the person understands and can manage without overload. [2]

Interpreting Findings

Supportive: A clinically meaningful, reproducible mismatch that the examiner can explain in relation to the rest of the neurological examination.

Incongruity: A finding that conflicts with established clinical expectations. Internal inconsistency: A meaningful mismatch between related functions, beyond ordinary fluctuation.

Negative or indeterminate: No informative change, an absent symptom, an unsafe task or a pain-limited comparison does not settle the diagnosis. Record the limitation and the remaining differential.

Alternative explanations: Backward improvement can occur in task-specific dystonia; rhythm can help parkinsonian freezing. Fear of falling, sensory loss, pain and joint restriction can alter gait too. An unfamiliar gait is not sufficient evidence of FND. [1]

Keep the diagnostic finding separate from endurance, fall risk and community mobility. It does not measure repeated walking with shopping, stairs at home or the need for an aid. Link the finding to an appropriate rehabilitation assessment, without assuming that brief improvement predicts treatment response.

Explaining the Result

An editorial example, to adapt only to a finding actually observed:

“We saw a clear change in your stepping when the task changed. Let me show you what changed and why it helps us understand the movement problem. It does not mean you chose the difficult walk, or that you can reliably reproduce the easier one outside this room.”

Then explain the specific clinical reasoning, possible coexistence and what remains to assess. Ask what happens on the person’s usual routes. If the comparison was inconclusive, say so plainly: “We could not make a useful comparison safely today.” See the symptom page for daily-function context.

Evidence and Limitations

The 2020 sign-based review offers an expert clinical framework and illustrative videos, not a prospectively validated score or one sensitivity/specificity estimate for all these tasks. Full text was reviewed for this expansion. [1]

Gandolfi and colleagues compared 29 people with functional gait disorder with 49 healthy participants during instrumented single- and dual-task walking. Some performance measures differed, while effects on their automaticity measure did not. Healthy controls do not establish specificity against neurological gait mimics. Despite the paper’s “biomarker” title, these findings do not validate a universal bedside rule. The primary abstract was checked; full-text methods and individual thresholds remain to be reviewed. [2]

Targeted update: September 30, 2026. This is not a systematic review of every gait sign. Each proposed standalone method needs its own validation review. A treatment response should not be substituted for diagnostic evidence.

Media and Accessibility

Film the same short walkway in this order:

Forward walking at the person’s comfortable pace.
One selected comparison task.
A second comparison only if clinically useful and safe.
A clinician summary explaining the observed change.

Use a wide side view and a front or rear view, but show the complete uninterrupted pass before any close-up. Keep the usual aid and safety person visible. Do not stage a fall, ask for repeated knee buckling or use slow motion to sensationalize the gait. Captions should identify the task and observed change, not diagnose from appearance alone.

Obtain explicit recording and educational-use consent. Provide captions, a transcript and a text description of each comparison, including support and stopping points. Do not require readers to watch a symptom video to understand the page. No media has yet been added.

Research and Sources

The clinical outline comes from sign-based guidance. The instrumented study addresses a narrower research question; its findings must not be generalized to every dual task or gait phenotype.

Citation	Figure	Full citation
[1]	—	Nonnekes J, Růžička E, Serranová T, Reich SG, Bloem BR, Hallett M. Functional gait disorders: a sign-based approach. Neurology. 2020;94(24):1093–1099. FND-CIT-0020. https://doi.org/10.1212/WNL.0000000000009649
[2]	—	Gandolfi M, Fiorio M, Geroin C, et al. Dual tasking affects gait performance but not automaticity in functional gait disorders: A new diagnostic biomarker. Parkinsonism & related disorders. 2023;108:105291. DOI. PMID: 36764083. FND-CIT-0132.