Video report by ITV News Correspondent Juliet Bremner
Some 4.7 million people in England were waiting to start hospital treatment at the end of February, the highest number ever recorded.
It is the most people waiting for treatment recorded by NHS England since records began in August 2007.
In January, 4.59 million people were on the waiting list, and in December, it was 4.52 million.
The NHS' treatment backlog is widening and has built up during the pandemic as resources were diverted to support coronavirus patients.
The number of people who had been waiting more than a year for hospital treatment was 387,885 in February - the highest number since December 2007.
In the same month last year, the number was 1,613.
The number of people admitted for routine treatment in hospitals in England fell 47% in the space of a year - from 285,918 in February 2020 to 152,642 in February 2021. Although, February 2020 had 29 days rather than the usual 28 due to the leap year.
The year-on-year decrease in January was 54%, while in December 2020 the drop was 25%.
NHS England national medical director Professor Stephen Powis said: “Treating 400,000 patients with Covid-19 over the course of the last year has inevitably had an impact on the NHS.
"But it is a testament to the hard work and dedication of staff that they managed to deliver almost a million ops and procedures in the face of the winter wave and improve waiting times for them, along with A&E and ambulance services.”
NHS England highlighted staff carried out almost two million operations and other elective care (that is planned in advance) in January and February this year, while providing hospital treatment for nearly 140,000 Covid-19 patients.
Meanwhile, around two in five of all patients who were treated for the coronavirus were admitted in the first two months of 2021.
What impact does a delay in treatment have on patients?
Tracey Loftis, head of policy and public affairs at the charity Versus Arthritis said delays to treatment can lead to “serious physical and mental health implications”.
She added: “Delays to planned treatment can lead to serious physical and mental health implications, especially for those with arthritis who have debilitating pain or limited mobility.
“Whilst it is understandable that operations are cancelled at this time, thousands of people are having to endure longer periods of pain.
“People waiting for joint replacement surgery urgently need clear communication about their care, and support including advice on pain management and mental health and wellbeing.”
"For many people, waiting for a joint replacement operation, it's like their life is on hold"
"For many people, waiting for a joint replacement operation - it's like their life is on hold until they have the operation," Ms Loftis said.
Clearly at the moment there will be people who need support, need ongoing communication from the NHS about what is and what isn't happening, and also what we need to see is progress with the backlog for these sorts of operations."
What else did the NHS data release show us?
Data shows 1.9 million elective care for patients took place amid the winter surge of Covid infections and there were some 2.6 million A&E visits in that period, NHS England said.
It said a £1 billion elective recovery fund will help trusts catch up on the backlog, with every area of the country being asked to “maximise their capacity to provide care for as many urgent and non-urgent patients as possible”.
The number of people on waiting lists for diagnostic tests also soared.
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A total of 327,663 patients had been waiting more than six weeks for one of 15 standard tests, including an MRI scan, non-obstetric ultrasound or gastroscopy in February 2021. In February 2020, the number was 29,832.
The monthly total peaked at 571,459 in May 2020.
There were 8% fewer urgent cancer referrals in February 2021, compared to the same month in 2020. A total of 174,624 urgent cancer referrals were made by GPs in England in February 2021, compared with 190,369 in February 2020.
For January, the year-on-year fall was 11%. But in December 2020, there were 7% more urgent cancer referrals compared with December 2019.
Urgent referrals where breast cancer symptoms were present fell 10% from 13,627 in February 2020 to 12,199 in February 2021.
NHS England said 22,000 people began cancer treatment in February, in line with numbers for February 2020. And the 174,000 people being referred for cancer checks was twice as many as during the peak of the first Covid wave in April last year.
A&E attendances in March were up 10% year-on-year. But NHS England said this could be partly because of the lower-than-usual numbers for March 2020, the start of the coronavirus pandemic.
There were 1.7 million A&E attendances in March 2021, an increase from 1.5 million in the same month in 2020. Before the pandemic in March 2019, the number was 2.2 million.
Emergency admissions to A&E departments also rose from 427,968 in March 2020 to 503,913 in March 2021. In March 2019, there were 555,457 emergency admissions.
NHS England said the time taken for ambulances to reach “category one” patients, whose condition is classed as life-threatening, fell to six minutes and 47 seconds against a seven-minute target.