Tomkins dislocated his shoulder in training last week and reports suggested that the defender would play no further part in the campaign, but West Ham remain hopeful he will feature in the run-in.
"James Tomkins underwent successful surgery on his dislocated shoulder on Wednesday and will now commence his rehabilitation, with a view to him returning to fitness before the end of the season," read a statement from Stijn Vandenbroucke, the club's head of medical and sports science, on West Ham's official website.
West Ham also confirmed that Carlton Cole will be fit to face Sunderland on Saturday after a near month-long lay-off with a hamstring injury.
Enner Valencia's toe injury means he remains sidelined until after the international break, while Winston Reid is nearing a comeback from his hamstring complaint suffered against Chelsea on March 4.
