Thumb MCP UCL stress Xray view

Xray beam angle 90 degrees.

The view to demonstrate "gamekeeper's thumb" - instability of the ulnar collateral ligament of the thumb metacarpophalangeal joint. 

Here's another way to position for this, as described in Radiology Technology Journal: 70(5), p 465-9, 1999 
Below, the same view with and without applied stress:
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