England still have two games to play in this year's RBS 6 Nations - Italy at home and Wales at the Millennium Stadium - and boss Stuart Lancaster had been hopeful of calling on Croft in the latter stages of the competition.
Croft will play in back-to-back weeks for the Tigers for the first time in 12 months this weekend as Leicester tackle Sale - and Cockerill has called for calm over the player's international ambitions.
Four years ago Croft was a key factor for the Lions in South Africa and already the Leicester man has been talked about as a possible summer tourist - but Leicester are not looking too far ahead at present.
"Tom is now ready to play consecutive weeks for us," said Cockerill.
"He has metal work in his neck to hold everything together while it heals.
"What you don't want is the screws to be working loose and that's why he was only playing every other week, to control the amount of impact and vibration going through him.
"He's been doing that for two months and we have had no adverse reaction to that. He has looked more and more comfortable as he has played every week.
"He was scanned on Monday and his X-ray has been sent to the specialist, who is happy that it has healed enough.
"It will take months for it to be completely healed so we will still manage him, but Tom was looking good at the weekend and I am pleased for him, because it was a serious injury."