I'm also interested in above phenomenon which sounds much like an extrapolation of new symptoms I just began about 2-3 months ago and which are on the increase...tho much less powerful so far. I am in my 9th post-dx yr and 8th yr of Sinemet use. I have found this symptom different..... rendering any earlier PD challenge to balance as trivial. Though not yet forcing a fall, its push to (my) right and down is increasing. Also unfamiliar with "trunkeal" I am very interested in comments by list, by my neuro next meeting and furthur to me by Marty.