The number of operations cancelled at the last minute has hit a 10-year high.
Figures from NHS England show nearly 75,000 NHS operations were postponed at the last minute in 2015/16 and more than 5,000 patients then had to wait more than 28 days for them to be rescheduled.
This affects patients who had their operations cancelled at the last minute due to non-clinical reasons, such as beds or staff being unavailable.
It does not include patients told in advance of cancellations due to junior doctor strikes.
Under the NHS constitution, cancelled operations are supposed to be rescheduled within 28 days.
The data shows that 74,086 patients had their operations cancelled during 2015/16.
Some 5,063 patients (6.8% of the total) were then not treated within 28 days.
Clare Marx, president of the Royal College of Surgeons, said: "It is disappointing that the number of patients waiting for their cancelled operations to be rescheduled has hit the highest level in a decade. This is yet another indication of the pressure the NHS is under.
"Situations where patients have to wait longer for their treatment are highly stressful for them and their families and, in some cases, their condition could deteriorate. It is vital that access to healthcare must be provided at a time when patients can benefit most from the result.
"There are likely to be a number of factors behind this rise that Government and the NHS need to continue to tackle, including pressures in emergency departments, staffing shortages, and lack of bed availability due to rising delayed transfers of care.
"Industrial action may not have helped but the underlying causes are likely to be more strongly related to the broader pressures the NHS faces."