The utility of the scratch collapse test has been demonstrated in examination of 
patients with carpal and cubital tunnel syndromes and long thoracic and peroneal 
nerve compressions. In the authors' clinic, this lesser known test plays a key 
role in peripheral nerve examination where localization of the nerve irritation 
or injury is not fully understood. Test utility and accuracy in patients with 
more challenging presentations likely correlate with tester understanding and 
experience. This article offers a clear outline of all stages of the test to 
improve interrater reliability. The nuances of test performance are described, 
including a description of situations where the scratch collapse test is deemed 
inappropriate. Four clinical scenarios where the scratch collapse test may be 
useful are included. Corresponding video content is provided to improve 
performance and interpretation of the scratch collapse test.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, V.