Surgery for knees, hips and eyes is under pressure across the NHS, with evidence of rationing to save money, a report suggests.
Data from health analysis firm Dr Foster highlighted the effects of recent austerity, with some operations at their lowest level for several years.
The number of knee operations has been rising steadily since 2002, against a background of an increasingly ageing population, but fell for the first time last year.
In 2011, there were 82,122 operations, dropping to 81,572 in 2012.
And while cataract operations had also been rising, the number started dropping in 2009 and there are now fewer taking place than in 2008.
In 2008 there were 326,456, in 2012 the total fell to 321,957.
While the data alone cannot shed light on whether patients' needs are being met, a spokesman for Dr Foster said it was likely that NHS trusts were changing the thresholds at which people qualify for treatment.
This means people who would have got an operation in the past either do not qualify or may have to wait for their condition to get worse.
The report shows that 24% of people live in areas where the number of hip, knee and eye operations have been cut, while there has been a rise in avoidable admissions to hospital.
Some 41 areas are identified as having rise rates of avoidable emergency admissions.
The report also reveals that, in some parts of the country, spending on important treatments is being reduced while resources are "wasted" on avoidable or less effective care.
Less effective procedures include removing tonsils, knee "washes" and injections for back pain - treatments that have been shown to have little or no clinical benefit.
Dr Foster said Croydon in south London and west Cheshire were two areas where spending on knee, hip and eye operations has dropped while, at the same time, there has been an increase in spending on ineffective treatments.
Across the whole of England, 3% of people live in areas where effective treatments are being cut while the amount of money wasted on ineffective treatments has increased, the study said.
But, overall, parts of the NHS were found to be cutting their spend on ineffective operations while maintaining or increasing the numbers of hip, knee and eye operations.
Areas including Wigan, west London, east Leicestershire and Rutland, and Cornwall were found to have maintained or increased their numbers of hip, eye and knee surgery while keeping unnecessary emergency admissions low and decreasing ineffective treatments.
Across England, 7% of people live in such areas while 15% live in areas where unnecessary hospital admissions have been reduced and knee, hip and eye operations remain stable.
Dr Foster director of research Roger Taylor said: "We have highlighted these figures to GPs so that throughout this period of austerity money can be spent wisely providing care for people that need it.
"Across England as a whole, austerity has caused the NHS to be more careful about the way it spends money on planned care and to cut waste.
"But there are significant differences in how well commissioners are coping with the financial squeeze. The quality of the service you can expect to get from the NHS will increasingly be affected by how well your local commissioners manage their budgets."
Steve Winyard, head of campaigns at the Royal National Institute of Blind People (RNIB), said: "It is scandalous that some commissioners continue to restrict access to cataract surgery through the use of arbitrary thresholds; and that they do so without a robust evidence base and without being able to demonstrate that they will not harm patients.
"This postcode lottery is simply unacceptable.
"NHS 'efficiency savings' achieved by cutting cataract operations are a false economy as denying treatment leaves patients at risk of depression, social isolation and fall-related hip fractures, which are more costly to treat.
"Everyone with a sight-threatening condition deserves early access to treatments that will delay or halt sight loss."
Katherine Murphy, chief executive of the Patients Association, said: "Here is the evidence of an NHS under financial strain where the Nicholson Challenge is really starting to bite and yet again sadly those who will be most affected will be patients on waiting lists for knee, hip and cataract surgery.
"Those responsible in the NHS for making harsh decisions in order to satisfy their financial directors and boards should remember that patients are in pain but yet their operations are being cancelled.
"The NHS is a national health service and we must never get to a situation where dependence on your postcode determines whether or not you receive NHS treatment. We cannot, and should not, have a postcode lottery within healthcare."
Colin Howie, vice-president of the British Orthopaedic Association, which represents orthopaedic surgeons, said NHS organisations which restrict access to hip and knee replacements were denying needy patients the chance to regain their mobility.
"It's disappointing that the health service is failing to provide treatments of proven benefit to patients that make a substantial and real improvement in their lives," he said.
The charity Age UK said the Dr Foster figures showed that NHS organisations were guilty of "ageism" in deciding who deserved which treatments.
Caroline Abrahams, its charity director, said: "It is distressing that ageism remains deeply rooted in the way older people are treated by the NHS, despite being outlawed by legislation.
"Too often decisions are made on age alone with informal 'cut-offs' imposed on whole services."
Unison head of health Christina McAnea said: "It is shameful that rationing is leaving patients in pain and waiting for months on end before they receive life-enhancing operations.
"In yesterday's Autumn Statement the Chancellor said again that the NHS is protected from Government cuts - try telling that to someone waiting for a cataract operation which would literally change their life.
"The financial pressures on parts of the NHS are building and it cannot be right that the treatment patients receive should depend on the area they live in.
"Without timely hip and knee surgery, the need for one operation can easily be doubled to two, as a patient's condition deteriorates. Waiting longer ends up costing the NHS more."