Wrinkling Test
- Fysiobasen
- Oct 3
- 2 min read
The Wrinkle Test is used to evaluate nerve integrity in the hand by analyzing the autonomic response to prolonged water exposure. It is particularly useful for diagnosing digital nerve injury or denervation of the fingers, and may be especially valuable in assessing patients who have lost sensory function¹.
Test execution
Patient position
The patient is seated in a comfortable position.
Examiner preparation
A bowl or container is filled with warm water.
Test procedure
The patient’s affected or tested hand is submerged in the water.
The hand remains immersed for 10–30 minutes.
After the set time, the hand is removed, and the examiner inspects the fingertips for wrinkling.
Interpretation
Positive test: Absence of fingertip wrinkling in one or more fingers indicates reduced nerve function or denervation.
Negative test: Normal fingertip wrinkling in all fingers suggests intact nerve supply¹.
Diagnostic validity and evidence
Rubin et al. reported that the Wrinkle Test demonstrates:
Sensitivity: 69.5%
Specificity: 62.5% for diagnosing digital nerve injury².
According to the Journal of Hand Therapy, the test is particularly useful in infants and young children, as it does not require cognitive understanding or active participation from the patient³.
Clinical relevance
Advantages
Simple and non-invasive method to assess nerve function.
Particularly valuable in patients unable to provide verbal feedback, such as children or individuals with cognitive impairment.
Limitations
Individual variation in skin response to water may affect accuracy.
Moderate specificity means the test should be combined with other clinical assessments for greater diagnostic reliability.
Conclusion
The Wrinkle Test is a useful clinical tool for evaluating digital nerve integrity, especially in patients unable to actively participate in testing. Although it has only moderate sensitivity and specificity, it provides significant diagnostic value as part of a multimodal assessment strategy for nerve injury.
References
Image by Nicole Hanusek, 2007, Mike's wrinkly hands, Flickr, [Assessed on 26, November, 2022]
Rubin G, Orbach H, Rinat B, Shay R, Rozen N. The utility of diagnostic tests for digital nerve injury. Annals of Plastic Surgery. 2020 Jan 1;84(1):73-5.
Packham T, Ahmad A, Huxtable M, Jacob N, Schutten D, Gjertsen D, DeMatteo C, MacDermid JC, Bain J. Skin Temperature Asymmetry and Stimulated Skin Wrinkling: Reliability and Validity for Evaluating Obstetrical Brachial Plexus Injuries. Journal of Hand Therapy. 2019 Oct 1;32(4):550.
Dr thomas McClellan In the Clinic: Fingertip Skin Wrinkling in Water and Digital Denervation Available from: https://www.youtube.com/watch?v=GIuVr9OgT_M
