BACKGROUND: The scratch collapse test is a recently described provocative test 
for diagnosis of peripheral nerve compression.
METHODS: The scratch collapse test was studied prospectively in 24 consecutive 
patients with a diagnosis of common peroneal nerve compression neuropathy. The 
diagnosis was confirmed by history, physical examination, and electrodiagnostic 
testing. Provocative testing by the scratch collapse test and Tinel's sign was 
performed.
RESULTS: The scratch collapse test showed a sensitivity of 0.77 and a 
specificity of 0.99, while the Tinel's sign showed 0.65 and 0.99, respectively.
CONCLUSION: The scratch collapse test is a sensitive and specific provocative 
test that compares favorably to existing clinical tests and aids in the 
diagnosis of common peroneal neuropathy.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II.