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Published on: March 16, 2015
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The Shoulder-Tapping Sign: A Highly Specific Indicator of Neurocognitive Disorders.
Brad T Tyson1, Laszlo A Erdodi2, Matthew Holcomb3
1Eastside Neuroscience Institute, EvergreenHealth Medical Center, Kirkland, Washington.
Summary
The shoulder-tapping sign (STS) is a quick test for neurocognitive disorders. A positive STS is highly specific for these conditions, aiding in diagnosis during brief mental status exams.
Area of Science:
- Neurology
- Neuropsychology
- Cognitive Science
Background:
- Perseveration is a recognized indicator of neurological dysfunction.
- The shoulder-tapping sign (STS) is an easily identifiable motor perseveration.
- STS involves the inappropriate continuation of a response.
Purpose of the Study:
- To evaluate the diagnostic value of the STS for identifying neurocognitive disorders.
- To assess the STS in patients referred for neuropsychological evaluation.
- To determine the utility of STS in cognitive assessments.
Main Methods:
- Administered a five-step verbal command to 400 patients with suspected cognitive decline.
- Defined a positive STS as tapping either shoulder more than twice.
- Calculated sensitivity, specificity, and likelihood ratios for STS as a diagnostic marker.
Main Results:
- The STS was positive in 23% of patients, with 96% having a neurocognitive disorder.
- STS showed high specificity (0.96) but low sensitivity (0.28) for neurocognitive disorders.
- The sign was present in 38% with dementia and 21% with mild neurocognitive disorder.
Conclusions:
- The STS is a highly specific indicator of neurocognitive disorders.
- Despite low sensitivity, STS is a valuable addition to cognitive assessment tools.
- A positive STS can be a key feature in brief mental status examinations for neurocognitive disorders.
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