I am sorry but I can't get a close enough look at this issue to tell what it is either.  I have searched for diseases or insects that might cause this but had no success.  Are you sure that it's not the flowers that either aborted or were frost-damaged or somehow died prematurely, and then just stuck on the stem?  It seems to occur just where the flowers and berries are borne, which would be odd for either a disease or insect.  By this time, are they dry and just crumble off if you rub them?  Interesting!

Jeana M. 

You might take a very close look (magnifying glass) to see if there are scale, aphids, spider mites, or thrips that have colonized there.  Of course, once the flowers are dead all of them but scale would move on.  But I would try to see if it looks like it could be insect damage, and then next spring, you could really be on the lookout for pests that may be attacking the flower buds.  You could treat with horticultural oil now, as it will kill some insects, but it won't kill scale this time of year. Spray again in 7 days.