That by itself without any other MS symptoms is not likely to be MS. Spasticity is not generally an early sign and wouldnt be the first and only sign. Also it wouldnt likely effect a single finger selectively.
Trigger finger is a specific thing but its not the only thing that can cause the finger to do that. So when they say it's not trigger finger that doesnt mean it isnt a primary injury to the muscle or tendon. Xrays only show bones so probably wouldnt have be very helpful. Nothing is impossible but the odds that is MS, in the absence of other MS symptoms is extraordinarily low.

Thank you all! Mo74, she has a ton of MS type symptoms, but they certainly could be from her EDS/POTS/CRPS/Fibromyalgia/RLS so it's tough to know. She has had eyeball pain on and off for over 2 years, times her legs completely stop working (brain cannot make legs hold her up or move whatsoever, frequent headaches, zinging senstations from behind her ear down her jaw line and elsewhere every now and then since she was maybe 5, joint pain, nerve pain, dizziness/vertigo, feeling like she's going to pass out, etc, etc. This finger thing is just the latest in mystery symptoms.

PS..Dupuytren's contracture? I forgot to mention that but check it out and see if that fits. The hand surgeon will know. Good luck hope she feels better soon.

So asked my Neuro & he said it could b spasticity w/MS

Possibly. The orthopedic hand MD did not have an answer at all and did not do any xrays. She was only instructed to pry it open and put it under her leg regularly to keep that finger flat/straight along with her other fingers. She will see Ortho again at the beginning of next week, but it seems the MD and PT are stumped. I was concerned that maybe this was an indicator of MS that the doctors have missed. Wondering if anyone else has experienced this?