The 19-year-old was given lengthy treatment before being carried off on a stretcher during a win over Annan Athletic in the Petrofac Training Cup on Saturday, with his club concerned initially that he would not return until next year.
Paterson visited a specialist in Bradford yesterday, however, and was given a far more promising prognosis. Indeed, the teenager was optimistic about his rehabilitation following his surgery. In a message on Twitter, he wrote: "Op went well and on to the recovery now. Will be back in no time."
Neilson - who had intimated his concern that Paterson had sustained ligament damage following the win over Annan - echoed that optimism, acknowledging that the defender is expected to resume full training in just two months. That is a relief for a coach who had suspected that he would be without one of his talented young players for the first half of the SPFL Championship campaign.
"We had Callum looked at and, once it was realised that the injury wasn't as bad as we first thought, went ahead with surgery," said Neilson, whose side will begin their league season away to Rangers on August 10. "The operation - a medial menisectomy - was a tidy-up job which went absolutely fine. Because of the nature of the injury, we believe Callum will return to the training field in around a couple of months.
"It will still keep him on the sidelines for the foreseeable [future], but because we could've been looking at six months out or longer, it's a huge relief that it isn't as bad as that. Callum will start his rehabilitation straight away and I'm sure he will come back better than ever."
The relief and renewed positivity around Tynecastle was also added to by confirmation that Jamie Walker has signed a new contract, tying him to Hearts until 2017. The winger has emerged as one of the club's brightest talents, excelling last season after his promotion into the first team, and was understood to be the subject of interest from clubs wishing to profit from Hearts' financial perils last term.
A broken foot helped bring an end to that speculation midway through the campaign, with the Edinburgh club having taken advantage instead by tying up the 21-year-old on a new three-year contract. Walker - who has made 56 first-team appearances for Hearts, scoring five goals - joins the likes of Paterson, Gary Oliver, Sam Nicholson, Kevin McHattie, Dale Carrick and Jack Hamilton by committing to a new deal.
Those supporters who helped to rebuild the club's finances by paying monthly donations will also feel closer to the club when they become members of the Foundation of Hearts officially next month.
Ian Murray, chairman of the FoH chairman and the Labour MP for Edinburgh South, has written to all contributors to inform them of the process as the fans' body prepares to take the next necessary step in their complex takeover of the Tynecastle club.
As a private company which is limited by guarantee, the fans' organisation is required by law to turn their 'pledgers' into full members, with this process due to take place automatically when supporters make their August payments. Membership will allow backers to vote on FoH business, with the group's inaugural annual general meeting expected to take place in either October or November.
FoH have already ploughed £1m into the club to help the process of clearing over £500,000 of football debt, a substantial sum which was taken on when businesswoman Ann Budge bankrolled the club's exit from administration last month. The organisation boasts in excess of 8000 monthly contributors, who will also finance £1.4m as a group towards the club's annual budget in each of the next two seasons.
Any surplus funds which are raised by FoH as a result of contributions will then be saved to allow the fans to pay off the £2.5m 'loan' from Budge and her BIDCO body within the next five years. That process is intended to ensure that the supporters can take full control of a club brought back from brink during 12 months of administration.