A Critical Appraisal of the Whack-a-Mole and Swivel Chair Signs in the Diagnosis of [FMD]s 2024 Lagrand, Edwards et al

Full title: A Critical Appraisal of the Whack-a-Mole and Swivel Chair Signs in the Diagnosis of Functional Movement Disorders

Abstract

Background
The demonstration of positive signs during neurological examination is a cornerstone of the diagnosis of functional movement disorders, however, the available data supporting the diagnostic value of some of these signs is limited.

Objectives
To determine the diagnostic value (sensitivity and specificity) of the “whack-a-mole” (WAM) and “swivel chair” (SC) tests in patients with functional movement disorders (FMD).

Methods
We enrolled patients with functional and organic movements in the WAM test if they exhibited tremor, dystonia, myoclonus, chorea, or tics. For the SC test, patients with a gait disorder as their primary impairment were recruited. Two blinded movement disorder specialists rated the presence of these signs in edited videos.

Results
Inclusion criteria were met by 42 patients with FMD and 65 patients with organic movement disorders. Both tests demonstrated high specificity (means, 78% and 96%), but their sensitivity was low (means, 52% and 37%). Interobserver agreement for the WAM sign was 0.77 in the FMD group, against 0.28 in patients with organic movement disorders, whereas Movement Disorders Clinical Practice for Review Only for the SC sign was 0.69 in both groups.

Conclusions
The present study indicates that physicians must be cautious in the application and interpretation of these clinical signs in the diagnosis of functional movement disorders, and they should be carefully considered and used as necessary.

Paywall, https://movementdisorders.onlinelibrary.wiley.com/doi/10.1002/mdc3.13895

 

Uhhhh. OK. See, we've ALWAYS been at war with East Asia. The feud with West Asia didn't start recently, it was a long time coming, and we will win thanks to our long-time allies in East Asia.

Objectively, I'm really not sure if this is actually better than dunking poor women in water to check for their witchiness. Bring out your calipers, folks! Gotta measure those skulls for signs of barbarism and stuff, but you have to do it carefully and used as necessary. Or maybe they could ask that folksy dude Phil Parker and what his hover hands think of it!