False positive and negative results in Allen test

Area of Science:

• Vascular Surgery
• Diagnostic Imaging
• Hand Surgery

Background:

• The Allen test is a clinical maneuver to assess collateral circulation in the hand.
• Accurate assessment of palmar arch patency is crucial for preventing complications, especially before radial artery harvesting or in peripheral arterial disease.
• Understanding factors leading to false results is essential for reliable diagnostic application.

Purpose of the Study:

• To analyze the factors contributing to false-positive and false-negative results in the Allen test.
• To evaluate the diagnostic accuracy of the Allen test compared to arteriography in patients with peripheral arterial disease and in healthy individuals.

Main Methods:

• Arteriography was performed on 44 hands with peripheral arterial disease under independent compression of radial or ulnar arteries.
• The Allen test was applied to 140 normal hands and 52 hands with arterial occlusion.
• Results were compared with arteriographic findings to identify discrepancies.

Main Results:

• False-positive Allen tests were attributed to arterial spasm in the uncompressed artery or erroneous compression of both arteries.
• False-negative results were linked to improper compression technique or occlusion of both radial and ulnar arteries.
• No false-positive results were observed when the Allen test was carefully performed and compared with arteriography.

Conclusions:

• The Allen test is a reliable diagnostic tool for assessing palmar arch patency when executed with proper technique.
• It is valuable for pre-operative evaluation and post-operative follow-up after reconstructive surgery involving the radial and ulnar arteries.
• Careful performance is key to avoiding diagnostic errors and ensuring its utility in vascular assessment.