Functional Gait Disorder: Diagnostic Technique Inventory

Expanded pages: sign-based gait comparison and swivel-chair assessment. Further individual evidence reviews remain pending.

Original thirteen entries

Knee buckling with preserved support

The clinician compares visible knee yielding with demonstrated leg strength and balance. A mismatch can support functional gait disorder, but negative myoclonus, pain and other causes can also buckle knees. Never withdraw support to see whether someone falls. [1][2]

Dragging and uneconomic postures

The examiner describes dragging, excessive slowness or energy-demanding postures and compares them with strength and balance. These are phenotype clues, not diagnostic shapes: dystonia, spasticity and other disorders may look unusual. [1][3]

Cautious “walking on ice” pattern

A wide-based, hesitant gait with unexpected preservation of balance can contribute to a functional assessment. Fear of falling and vestibular or sensory disease can produce similar caution. The clinician must show the actual inconsistency rather than diagnose from appearance. [1][3]

Dual-task walking

Walking is compared with walking while carrying out another safe task. Unexpected improvement may support a functional pattern. Other disorders can also respond to attention or cueing; instrumented research is promising but not a universal diagnostic rule. [1][4]

Backward walking

A safely guarded comparison may reveal substantially better movement backward than forward. This is a supportive observation, not a standalone test, because task-specific dystonia and other gait disorders may also improve backward. [1]

Running or another automatic movement

Only when safe and clinically appropriate, a different movement may reveal capacity absent during ordinary walking. Improvement is an observation to explain, not proof or a requirement. Many patients cannot safely undertake such comparisons. [1]

Rhythm and externally cued walking

A clinician compares gait with a tolerable external rhythm or cue. Improvement may show task-dependent access to movement but is not specific: Parkinsonian freezing and other disorders can respond too. [1]

Tandem gait

Guarded heel-to-toe walking may reveal preserved balance despite apparent instability in ordinary walking. Unusual compensatory movements require context. This comparison must not expose someone to a fall and has no universal standalone accuracy estimate. [1][2]

Romberg comparison

A supported standing assessment compares balance with eyes open and closed. Disproportionate sway without the expected loss of balance can be informative, but sensory or vestibular disease also changes performance. The examiner must be ready to prevent falling. [1][2]

Postural-response comparison

A clinician may compare responses to a carefully controlled balance challenge with ordinary transfers or walking. Inconsistency can be supportive; musculoskeletal limits and neurological postural impairment remain relevant. This is a guarded clinical examination, never a home push test. [1]

Swivel-chair test

The person’s ability to propel a wheeled chair with their legs is compared with walking. Original research and later blinded testing support cautious use; low sensitivity means many functional gait disorders will not show the sign. Chair mobility does not prove safe walking. [5][6]

Effort-associated behaviour (“huffing and puffing”)

A video study examined marked effort-related sounds and expressions during standing and walking. Such behaviour can be supportive within a wider pattern, but pain, breathlessness and distress must be considered. It is neither evidence of pretence nor required for diagnosis. [7]

Instrumented balance and adaptation studies

Posturography and moving-platform research assess sway and gait adaptation under controlled conditions. These are specialist or research approaches with limited generalisability; group differences do not yet supply a routine individual diagnostic test. [8][9]

Research and Sources

Original citation numbering is retained. The detailed pages distinguish the studies reviewed in full from abstract-only access; the remaining inventory evidence awaits fresh individual review.

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]	—	Daum C, Gheorghita F, Spatola M, et al. Interobserver agreement and validity of bedside ‘positive signs’ for functional weakness, sensory and gait disorders in conversion disorder: a pilot study. Journal of neurology, neurosurgery, and psychiatry. 2015;86(4):425-430. DOI. PMID: 24994927. FND-CIT-0130.
[3]	—	Hayes MW, Graham S, Heldorf P, et al. A video review of the diagnosis of psychogenic gait: appendix and commentary. Movement disorders : official journal of the Movement Disorder Society. 1999;14(6):914-921. DOI. PMID: 10584664. FND-CIT-0143.
[4]	—	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.
[5]	—	Okun MS, Rodriguez RL, Foote KD, Fernandez HH. The “chair test” to aid in the diagnosis of psychogenic gait disorders. The neurologist. 2007;13(2):87-91. DOI. PMID: 17351529. FND-CIT-0127.
[6]	—	Lagrand TJ, Brusse-Keizer M, Charmley A, et al. A Critical Appraisal of the Whack-a-Mole and Swivel Chair Signs in the Diagnosis of Functional Movement Disorders. Movement disorders clinical practice. 2024;11(1):63-68. DOI. PMID: 38291841. FND-CIT-0181.
[7]	—	Laub HN, Dwivedi AK, Revilla FJ, et al. Diagnostic performance of the “Huffing and Puffing” sign in psychogenic (functional) movement disorders. Movement disorders clinical practice. 2015;2(1):29-32. DOI. PMID: 25961068. FND-CIT-0145.
[8]	—	Wolfsegger T, Pischinger B, Topakian R. Objectification of psychogenic postural instability by trunk sway analysis. Journal of the neurological sciences. 2013;334(1-2):14-17. DOI. PMID: 23932398. FND-CIT-0160.
[9]	—	Lin D, Castro P, Edwards A, et al. Dissociated motor learning and de-adaptation in patients with functional gait disorders. Brain : a journal of neurology. 2020;143(8):2594-2606. DOI. PMID: 32779724. FND-CIT-0117.