RT Journal Article
SR Electronic
T1 “Stretched Slinky” Sign
JF Neurology: Clinical Practice
FD Lippincott Williams & Wilkins
SP e121
OP e123
DO 10.1212/CPJ.0000000000200075
VO 12
IS 5
A1 Wilson K.W. Fung
A1 Alfonso Fasano
YR 2022
UL http://cp.neurology.org/content/12/5/e121.abstract
AB Objective Functional tremor (FT) is the most common functional movement disorder, although its diagnosis can be challenging. Archimedes spiral drawings can be helpful in eliciting additional signs associated with tremor. Here, we present examples of an unusual looping of Archimedes spirals only seen in FT.Methods Clinical information regarding demographic data, clinical history, and examination findings (including Archimedes spiral drawings) and investigation results of patients with FT in the movement disorders clinic were reviewed.Results Three paradigmatic patients with FT demonstrated a unique looping appearance of Archimedes spiral drawings, akin to the appearance of a stretched slinky. The degree of randomness of the spirals varied from patient to patient and often mirrored tremor severity, regardless of the diagnosis.Discussion The clinical hallmarks of a FT include a variable combination of positive signs, such as inconsistency (variability and distractibility), incongruence with known tremor syndromes, entrainment, and coactivation, although these findings might not always be present. We describe a unique appearance of spiral drawings, which could add as another clinical sign for FT. Consider looping of spirals as another diagnostic clue to FT.