There actually is an orthopedic hand problem called 'trigger finger' or stenosing tenosynovitis BUT the finger gets "stuck" bent, rather than being unable to bend.
http://orthoinfo.aaos.org/fact/thr_report.cfm?Thread_ID=168&topcategory=
http://www.mayoclinic.com/health/trigger-finger/DS00155
Sometimes an inflammatory nodule developes on the extensor tendon (along the top of the hand) which 'hangs up' within the tendon sheath and prevents bending the finger.
It seems much more likely that what Jim and your friend are describing is a 'trigger flinch'; or an involuntary inability to contract the trigger finger despite a voluntary 'command' to do so. This is one (of many and most often multifactorial) flinch that can usually be 'cured' with a release trigger.

Last edited by revdocdrew; 04/29/07 04:22 PM.
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