The influential 35-year-old suffered the injury in training, after struggling with a succession of monir knocks, and must now give the bone time to heal
Shrimpers physio John Stannard said: "We had monitored the situation but that was the final straw that broke the camel's, or should I say goat's, back.
"Everybody is disappointed, none more so than Shaun, who is eager to be involved."