First time posting here, though I've lurked for a bit. We have a daughter just under 4 months old now who has a preliminary diagnosis of CMTC with what we believe is a VM in her left wrist - that hand also swells/becomes puffy when she's sleeping or occasionally when she's nursing, but with a little movement or if we rub it gently, the swelling quickly resolves.
We just had the big MRI/MRA done yesterday so waiting on results for that. We've definitely noticed that she has less muscle tone in her left arm and arm (with the CMTC and VM), but she seems to not favor the weaker side so far (we'll see once she starts crawling and walking). We've tried to measure carefully but haven't noticed any length discrepancies either, just the girth. She's otherwise a very happy, laughing, smiling baby, full of energy, and is ahead of all of her developmental milestones, which is a delight for us.
Otherwise, we're also in the wait-and-see holding pattern.
Best wishes to you all!