Sometimes attached items (e.g. torches, signs) are dropped when a game is loaded.

If block A (solid) is in chunk 1, and a sign/torch is attached to one side of block A (but in another chunk, say, chunk 2), then if chunk 2 is loaded preceding chunk 1 when re-entering the game, then that sign/torch will be dropped without being interrupted.
This problem is quite frequent in 1.1.0.55.