The Royal National Orthopaedic Hospital is perhaps the leading centre of its kind in the NHS. It treats patients from all over the country and plays a key role in training surgeons for the rest of the health service.
But while the quality of care is second to none, the buildings patients are treated in leave a lot to be desired.
A host of adult wards are housed in buildings clad in corrugated iron which are linked to an operating theatre by a sloping corridor. It is so steep that patients have to be towed back on to wards by an electric vehicle.
The problem the hospital, in Stanmore, Middlesex, on the outskirts of north west London, has faced like many in the NHS is a lack of investment in its buildings.
The wards and corridor in question were only built as a temporary facility in the 1930s to treat TB patients. But as demands on the health service have increased it has been pressed into permanent use.
This is not the only problem, however. In total, 61% of the estate is classed as not suitable.
While some of these areas include office space, other clinical areas are also affected. For example, imaging facilities - X-rays, CT scans and MRIs - are not located together, while physio and occupational health rooms are considered too small.
Mark Masters, the hospital's director of estates and facilities, said it means staff are left do their best in the circumstances.
"We have been managing the ageing infrastructure for many years and staff work hard to maintain high quality patient outcomes.
"This is supported by a number of clinical and financial reviews, which conclude that despite the infrastructure, staff continue to provide high quality and in some cases, world class services."
The trust has been wanting to push ahead with a major redevelopment for years. It has received initial approval from government to press ahead with its plans, but has yet to find a private sector backer or get the final go-ahead for its business plans.
Unfortunately, the situation at the trust is mirrored in many other parts of the health service.
Nearly a fifth of the NHS estate is classed as not suitable either because of concerns over space, layout or a lack of facilities. In total, there are more than 30 hospitals with 50% or more of their estate not up to scratch. A host of mental health units and community hospitals are also affected.
In the centre of London, Great Ormond Street Hospital has its own problems. Some 35% of its estate is not good enough.
This includes single rooms that are so small staff struggle to get all the equipment in, while parents are sometimes forced to sleep in armchairs or ready beds as they are not big enough for proper beds.
Some of the wards are too small too. In total, about a quarter of beds are located in this wing of the children's hospital. The trust has plans to build new facilities, but it is still £95m short in its fund-raising.
A spokesman for the trust said: "We know some of our facilities are not what we would wish for families and for our staff but we are always determined to deliver high quality safe care."
Elsewhere in the capital there are hospitals that have had major investment which are still struggling to meet the standards.
Kingston Hospital has undergone a major PFI project to build a state-of-the-art surgical centre, but 55% of its buildings are still deemed not suitable. None of these areas is in the new part of the hospital, but a significant number of areas where patients are seen are still affected.
And despite the investment in new hospitals over the past decade - there have been more than 100 PFI projects - there are still significant chunks of the NHS estate which date back to before the start of the NHS in 1948.
Parts of the North Staffordshire Royal Infirmary in Stoke were built in the 1860s under the Poor Laws.
In total, 83% of the hospital is unsuitable, making it one of the worst sites in the country.
Wards are spread out across the site, leaving them too far away from diagnostic suites and operating theatres. There is also a lack of basic amenities such as toilets.
The buildings have also caused problems when the hospital has bought new equipment. In one case, £400,000 had to be spent adapting part of the building to accommodate new cancer equipment.
Meanwhile, the helipad for emergency patients has had to be situated on the other side of the hospital to trauma care. The facilities, in the trust's words, are "simply unsuitable".
However, the hospital is one of the lucky ones. It has got funding in place for redeveloping the site and is hoping to move out of the old buildings in 18 months time.
Many other of the worst hit places have drawn up plans. But with the capital budget for building improvements being cut and less appetite for privately-funded projects, it remains to be seen how many will see the light of day.
Bristol Royal Infirmary is treating patients in even older wards than the North Staffordshire. It has one building which dates back to 1735. The trust said the situation makes providing services "more difficult and less efficient to deliver".
But even more modern sites are struggling. Airedale Hospital in West Yorkshire opened in 1970, but 48% of its estate is now out of date. The A&E unit is badly affected. It does not have a separate children's area, while the cubicles are too small. Overall, 48% of the hospital is classed as not suitable.
Hospitals can also find themselves failing on what may seem relatively minor issues. For example, 60% of the Leicester General estate is below standard.
Storage space is an issue. The trust has set up three designated storage rooms to house everything from mattresses to heart monitors. But the trust says the situation costs it time and money as porters have to spend time ferrying the equipment back and forth.
The hospital has also run into problems with ensuring wards are close to areas such as imaging suites, operating theatres and intensive care. There is a corridor which is a third of a mile long. The trust has tried to minimise the issue by placing the sickest patients nearest to the core facilities.
Meanwhile, Birmingham's Good Hope Hospital does not have enough wash basins to meet standards which are designed to combat infection control. There is also too little single sex accommodation, which compromises "observation and patient dignity". The Heart of England trust said improving facilities at the hospital was a priority.
In all of these cases, there is no suggestion patients are at risk. In fact, most of the trusts score highly for their quality of care. But many acknowledge the facilities make providing those services more difficult than it should in a 21st century health system.