iPad propels Apple to top of PC market as growth stalls without tablets

Apple (s aapl) is the king of the PC heap, as long as you consider the iPad among those devices. Research firm Canalys does, and its most recent look at client PC sales, focusing on the fourth calendar quarter of 2011, shows the PC market growing, but mostly as a result of strong iPad sales for the year.

With Apple’s more than 15 million iPads shipped during the quarter, the worldwide PC market grew 16 percent year over year. Not counting tablets, of which the iPad is easily the most successful, the PC market actually shrank by 0.4 percent worldwide when compared to the same period a year ago, according to the Canalys data.

Apple’s success both with the iPad and its Mac computers allowed it to take top honors for the quarter, knocking HP (s hpq) to second place overall. Canalys says the lack of a valid HP tablet competitor, now that the TouchPad is shelved, will mean that HP will continue to struggle against Apple’s success.

The iPad wasn’t the only tablet to do well during the quarter, however. Canalys says that the Amazon Kindle Fire (s amzn) and Nook Tablet (s bks) also helped contribute to the success of tablets in the U.S. Amazon ranked as the second strongest tablet manufacturer worldwide, while Barnes & Noble took the fourth place spot.

All told, iPads accounted for 22 percent of all worldwide PC shipments in the fourth quarter of 2011, as measured by Canalys. It’ll be interesting to see what effect a new iPad launch in the coming months might have on the worldwide momentum of tablets, and the larger PC industry.