Injuries shouldn't be used as an excuse as there are plently of teams worse off that are still having success. The fact is that if your team isn't doing well with one or two key injuries (ie. Spezza) then your team wasn't that good in the first place.
Never said injuries were the only thing
Goaltending has been as big a problem as the sens have had. Seriously what team could win anything with the Elliot/Leclaire tandem this year.
Injuries, goaltending, coaching, general malaise...