WEBVTT 00:00:00.000 --> 00:00:03.100 (English captions by Jade Cheng from the University of Michigan) 00:00:03.100 --> 00:00:07.230 Testing for osteoarthritis of the thumb at the trapezium metacarpal joint is done by 00:00:07.230 --> 00:00:09.320 using the axial grind test. 00:00:09.320 --> 00:00:14.049 The examiner grasps the thumb and places an axial force with grinding. 00:00:14.049 --> 00:00:16.270 Reproduction of pain is a positive test.