Scratch Collapse Test
Purpose[edit | edit source]
Scratch Collapse Test is a diagnostic test for carpal tunnel syndrome and cubital tunnel syndrome.
Technique[edit | edit source]
Step 1. Patient position in standing or sitting.
Step 2. Ask the patient to flex the elbow 90 degree, then examiner applies internal rotation force over the distal arm while asking patient to resist.
Step 3. While in above position examiner applies scratch over the ulnar nerve ( compression area) on affected elbow, then immediately repeat above step 2.
Step 4. Positive test indicates quick loss of external rotation resistance on the affected side.
Evidence[edit | edit source]
| carpal tunnel syndrome | cubital tunnel syndrome |
|---|---|
| sensitivity 64% | sensitivity 69% |
| Specificity 99% | Specificity 99% |
| Positive Predictive Value 99% | Positive Predictive Value 99% |
| Negative Predictive Value 73% | Negative Predictive Value 86% |
| Accuracy 82% | Accuracy 89% |
