Last year, more than 2,000 people from Mid-Scotland and Fife received elective, day-case and outpatient procedures or appointments thanks to the NHS south of the border.
Those arrangements would be at risk should Scotland vote to break away from the rest of the UK in September.
In 2012-13, a total of 387 people from across Mid-Scotland and Fife received elective inpatient/day-case care from English hospitals.
A further 1,876 outpatients were seen by health professionals in England, the statistics confirmed.
In all, some 2,263 patients were dealt with south of the border, almost 300 more than the previous year.
Should Scotland separate from the rest of the UK, it would be regarded as a foreign country and such cross-border healthcare arrangements would no longer exist.
Additionally, the many patients from England who receive care in Scotland could lose out too.
The figures were revealed following a parliamentary question by Scottish Conservative MSP Mary Scanlon.
Mid-Scotland and Fife MSP Murdo Fraser said:
“These figures show just how strong the bond is between NHS Tayside, NHS Fife, NHS Forth Valley and the rest of the UK.
“This arrangement means that every year thousands of patients can get the care they need more quickly.
“However all of this would be jeopardised by a yes vote and the Scottish Government must be very careful not to sacrifice patient care for independence at any cost.
“Patients on both sides of the border benefit from the UK being together, and it would be very foolish to threaten that arrangement. The UK NHS benefits patients north and south of the border in so many ways.”