Between what we know should work and what actually happens lies a gap
More than 200,000 Britons undergo hip or knee replacement each year, yet fewer than one in a hundred return home the same day — despite NHS guidelines long recommending they do. The gap between policy and practice is rarely a failure of knowledge; it is a failure of understanding. A six-year, £3.8 million study now sets out to map the human terrain between what medicine knows and what medicine does, asking not only what is possible but why the possible so rarely becomes the actual.
- NHS guidelines have recommended same-day discharge for hip and knee replacements for years, yet fewer than 1% of patients actually leave hospital on the day of their operation.
- The cost of inertia is measurable: patients spend an average of 2.7 nights in hospital, beds remain occupied, waiting lists grow, and an estimated £40 million per year goes unspared.
- Day-case surgery, where it does happen, delivers faster recovery, lower infection rates, and a less disorienting experience — the benefits are real, but the barriers remain unmapped.
- The IDAPO study will spend its first phase listening — interviewing patients, caregivers, and clinicians to surface the fears, habits, and social constraints that keep same-day discharge from becoming routine.
- A new care pathway, built from those findings, will be tested in a randomized controlled trial, with the potential to fundamentally reshape how orthopedic surgery is delivered across the NHS.
Every year, more than 200,000 people in Britain have a hip or knee replaced — surgeries that arrive after years of pain and failed alternatives. The procedure itself is well-established. What happens afterward is now under scrutiny.
Despite NHS guidelines recommending same-day discharge, patients currently spend an average of 2.7 days in hospital after these operations. Fewer than 1% go home on the day of surgery. The gap between recommendation and reality is wide, and until now, no one has systematically asked why.
The IDAPO study — a six-year, £3.8 million research programme led by Dr. Ines Rombach of the University of Sheffield and orthopedic surgeon Antony Palmer of Oxford University Hospitals — is designed to do exactly that. The team will begin by reviewing existing evidence, mapping current practice across the UK, and conducting interviews with patients, caregivers, and clinicians. Their aim is to understand not just the clinical obstacles but the human ones: the anxieties, the practical limitations, the ingrained habits that keep same-day discharge rare.
Palmer, who has performed day-case replacements for over a decade, knows that patients who experience it are generally satisfied. But not everyone is a suitable candidate, and not everyone feels ready. Some lack adequate home support; some clinicians carry reservations rooted in training or genuine case-by-case judgment. These concerns have never been systematically mapped.
Once the barriers are understood, the team will design a new care pathway — complete with staff training, patient resources, and clear eligibility protocols — and test it in a randomized controlled trial. If it works, the NHS could save an estimated £40 million annually while treating more patients and improving their experience of care.
The study is, at its core, an acknowledgment that guidelines do not change practice on their own. Between what we know should happen and what actually does lies a space filled with real people and real constraints. The next six years will be spent learning to cross it.
Every year, more than 200,000 people in Britain have their hips or knees replaced. These are not elective surgeries undertaken lightly. They come after years of pain, after physiotherapy has stopped working, after weight loss and medication have failed to restore function. The surgery itself is routine, well-established, and effective. What happens after—where the patient recovers—is about to become the subject of a six-year, £3.8 million investigation.
Currently, patients undergoing hip or knee replacement spend an average of 2.7 days in the hospital. They arrive for surgery, wake in recovery, and remain as inpatients for at least one night before discharge. This has been the standard practice for decades. Yet the NHS guidelines have long recommended something different: same-day discharge. Patients should leave the hospital on the day of their operation and recover at home. The gap between what guidelines say should happen and what actually happens is stark. Fewer than 1% of hip and knee replacement patients are currently sent home the same day they are operated on.
The reasons for this gap are not obvious. Day-case surgery, when it does occur, produces measurable benefits. Patients recover faster. Infection rates drop. The experience of surgery—the anxiety, the disruption, the institutional feel of overnight hospitalization—diminishes. From a system perspective, the math is compelling: if more patients could be discharged same-day, hospitals would free up beds, reduce length of stay, and treat more people. The NHS estimates that shifting to day-case procedures could save £40 million annually. Yet the practice remains rare, and no one has systematically studied why.
The IDAPO study—Implementation of Day-case Hip and Knee Arthroplasty ensuring Optimal Patient Experience and Outcomes—is designed to answer that question. Led by Dr. Ines Rombach, a senior medical statistician at the University of Sheffield's Clinical Trials Research Unit, and Antony Palmer, an orthopedic surgeon at Oxford University Hospitals, the research team will begin by listening. They will review existing evidence, examine current practices across the U.K., and conduct interviews with patients, their caregivers, and the clinicians who treat them. The goal is to understand not just the medical barriers but the human ones—the fears, the practical constraints, the assumptions that keep same-day discharge from becoming routine.
Palmer, who has been performing day-case hip and knee replacements for more than a decade, notes that patients who undergo the procedure are generally satisfied with it. But satisfaction is not universal. Some patients and their support networks harbor doubts. Not everyone is medically suitable for same-day discharge; some lack the home environment, the caregiver support, or the social circumstances that make it feasible. The clinicians themselves may have reservations rooted in training, habit, or genuine clinical judgment about individual cases. These barriers—patient concerns, clinician hesitation, social factors—have never been systematically mapped.
Once the research team understands what is preventing day-case surgery from becoming standard, they will design a new pathway. This will include training for hospital staff, resources for patients, and clear protocols for identifying who is and is not suitable for same-day discharge. The pathway will then be tested in a randomized controlled trial, comparing it against current practice. If the new approach works—if it safely increases the proportion of patients discharged on the day of surgery while maintaining or improving outcomes—it could reshape how orthopedic surgery is delivered across the NHS.
The study represents a recognition that guidelines alone do not change practice. Between what we know should work and what actually happens in hospitals lies a gap filled with real people, real concerns, and real constraints. The next six years will be spent mapping that gap and building a bridge across it.
Notable Quotes
Most patients who undergo day-case surgery are pleased with their experience, but some patients and their support networks express reservations, and not everyone is suitable for day-case surgery for medical or social reasons.— Antony Palmer, orthopedic surgeon at Oxford University Hospitals
We have performed day-case surgeries for more than 10 years, and they are strongly encouraged by the NHS, yet only a very small portion of patients leave the hospital the same day. There is much to find out about day-case surgery, including patient and clinician views, barriers and facilitators of day-case surgery, and what represents the best clinical care for each individual.— Antony Palmer
The Hearth Conversation Another angle on the story
Why hasn't this happened already? The NHS has recommended day-case surgery for years. What's the actual barrier?
That's the question nobody has properly answered. It's not a medical problem—the surgery itself is safe and routine. It's something else. Maybe it's habit, maybe it's that clinicians worry about complications at home, maybe patients are scared to leave the hospital the same day they've been under anesthesia. We don't know because we haven't asked systematically.
But if it saves money and patients recover faster, shouldn't hospitals just do it?
You'd think so. But healthcare doesn't work that way. There's a difference between what's theoretically optimal and what feels safe to the people doing the work. A surgeon who's trained to keep patients overnight might genuinely believe that's better care, even if the evidence suggests otherwise.
What about the patients themselves? Are they refusing to go home?
Some might be. Others might not even know it's an option. And some genuinely shouldn't go home—they live alone, they have no support, they have other health conditions. The point is, we're making blanket decisions without understanding individual circumstances.
So this study is really about changing culture, not just changing protocol?
Exactly. You can write a new guideline, but if the people delivering care and the people receiving it don't understand why it matters or how to make it work, nothing changes. That's what the next six years are about.
And if it works, what does the NHS actually gain?
Forty million pounds a year. More patients treated. Shorter waiting lists. Fewer hospital beds occupied by people who could safely recover at home. But more importantly, patients get home sooner, which most of them prefer.