Which maneuver specifically provokes symptoms by compressing the space between the clavicle and first rib?

• A. Adson's test
• B. Costoclavicular test
• C. Halstead maneuver
• D. Allen maneuver

Answer: (B)

The space between the clavicle and the first rib is a defined window through which nerves and vessels pass. When you perform the costoclavicular maneuver, you pull the shoulders downward and back, effectively narrowing that costoclavicular space. That targeted narrowing can compress the subclavian artery and lower brachial plexus in that specific interval, provoking symptoms such as arm pain, numbness, or a dulled pulse in this position. Other maneuvers load different outflow spaces (like the scalene interval), so they don’t specifically isolate compression in the clavicle–first rib space.