The advantages of day surgery knee replacement

Knee replacements were first performed in the UK in the 1970s. Since then, they have evolved and improved, to the point where we can now offer day-surgery knee replacement options.

There are approximately 160,000 total hip and knee replacements performed each year in England and Wales1. Longer life expectancy, as well as changes in lifestyle, have resulted in an increase in osteoarthritis. Osteoarthritis is the leading cause of pain2, which can lead to the need for total knee or hip replacement surgery.

Osteoarthritis is the most common joint disease worldwide, affecting an estimated 10% of men and 18% of women over 60 years of age3.

X-Ray image of a patient's knees
X-Ray image of a patient’s knees

What is knee replacement day surgery?

One of the latest improvements in knee replacement surgery has been the introduction of day surgery options. This means that a patient is discharged from hospital within 23 hours of surgery and at Practice Plus Group hospitals, they are usually discharged the same day. This differs from outpatients who typically visit for short consultations and don’t need a bed. Outpatient knee replacement surgery is not offered at Practice Plus Group.

Types of day surgery knee replacement

Practice Plus Group are proud to be able to offer the full range of knee surgery options for outpatients. From partial knee replacement surgery to total knee replacement surgery, Practice Plus Group will accommodate your needs. The type of surgery you need will be determined by your doctor and you will be assessed on whether you are suitable to be an outpatient.

How long does knee replacement surgery take?

The surgery itself depends on the type of knee operation. A total knee replacement, for example, will likely take between 1-2 hours. Whereas a partial knee replacement normally takes around an hour. Most knee surgeries take between 1-2 hours.

Can you go home the same day as a knee replacement?

Put simply, yes. The aim of day knee surgery is to discharge patients within 23 hours of surgery. However, there are criteria that must be met for this to happen.

Total knee replacement same day discharge criteria

Following surgery, you will only be considered for same-day discharge if you can:

  • climb stairs
  • safely mobilise (with the aid of crutches or a walker)
  • manage your pain with appropriate medication.

Other reasons for not being discharged on the same day include patients simply having their operation too late in the day, experiencing pain, and issues with the wound. Those not discharged on the same day as their operation can typically expect short hospital stays.

Is day knee surgery safe?

Day knee surgery is just as safe as inpatient surgery provided you have been adequately prepared and selected.

What to expect

If you have day surgery knee replacement, it’s likely your operation will take place in the morning. As with regular knee surgery, you’ll need to prepare in the same way. This includes only drinking clear liquids and no solid food six hours before the procedure.

Pre-knee surgery

You’ll meet your dedicated orthopaedic surgeon and anaesthetist for a pre-assessment appointment. This may include x-rays and MRI scans of the affected knee. This is your opportunity to ask questions and prepare yourself for the procedure, so fire away. Once the clinician has assessed you, you’ll be given a date for surgery.

Before your surgery, you’ll be told what you can and cannot eat or drink. Your consultant will also advise what medication you should be taking, and which types to avoid. Some medication can stop your blood from clotting and cause increased blood loss during surgery.

During surgery

ou’ll be given either a general or spinal anaesthesia. This will be discussed with you by your anaesthetist. During the surgery itself, the worn ends of the bones in your knee joint are removed and replaced with metal and plastic parts.

The surgery itself depends on the type of knee operation. A total knee replacement, for example, will likely take between 1-2 hours. Whereas a partial knee replacement normally takes around an hour. Most knee surgeries take between 1-2 hours.

After outpatient knee replacement surgery

Recovery time will depend on the type of surgery you’ve had and how old you are. However, for everyone there is a specific list of do’s and don’ts to follow after surgery.


  • walk when it’s safe to do so
  • strengthen your knee with exercises given to you by your doctor
  • follow the advice of your doctor.

A few weeks after your operation, your doctor may suggest including exercises into your recovery. Cycling after a knee replacement is often recommended.


  • try to do too much too early
  • participate in sports with a high risk of falling (i.e. football, rugby, mountain biking etc)
  • drive straight after the operation. You won’t be able to drive until you can fully bend your knee.

Can you walk on the day of a knee replacement?

One of the criteria for being discharged on the same day of your knee replacement is to walk. This will be with the aid of crutches or a walker. If you cannot complete this task to the satisfaction of your doctor, you will be kept in hospital. You can then typically expect to be discharged the day after your operation.

What are the advantages of same day knee replacement surgery?

There are some advantages to this – for both the patient, and the health system. In 2019, 66% of surgical admissions within NHS England were being undertaken as day cases4. The benefits of day surgery include:

  • Fewer complications – because you are on the move quicker
  • Faster recovery – due to fewer complications
  • Reduced pressure on the NHS – faster turnaround of patients means using less NHS resource and reducing the backlog of patients waiting for surgery
  • Recover in the comfort of your own home
  • Reduced risk of deep vein thrombosis (DVT)
  • 100% of one-day joint patients would have the surgery again.

Does day surgery reduce the risks of complications?

If a patient leaves hospital within 24 hours, they will get up and move around in preparation for leaving the hospital. Research has shown that patients who mobilise early, make a quicker recovery and have fewer complications.

Early mobilisation increases blood flow around a patient’s body which decreases the potential risks of blood clots. According to a multicentre observational study on hip and knee surgery5: “in many studies, early mobilization protocols reduced the rate of complications/morbidity (e.g. respiratory decompensation/pneumonias, deep venous thrombosis/pulmonary embolism, urinary tract infections, sepsis or infection).”

What are the risks of outpatient knee replacement?

There are no added risks following day case knee surgery compared to regular knee replacement procedures. The only reasons you might be denied discharge on the same day as your surgery are an inability to carry out the following:

  • climb stairs
  • safely mobilise (with the aid of crutches or a walker)
  • manage your pain with appropriate medication.

How long does it take to recover from knee replacement surgery?

Day surgery means faster recovery due to early mobilisation and less knee pain and swelling from less complex procedures. A typical recovery time from knee replacement in the UK is around six weeks. This is likely to involve using crutches or walking aids for two to three weeks after the procedure and moving down to a single crutch by week four. By week six most patients are moving independently and are safe to drive.

Who is eligible for day surgery?

At Practice Plus Group, there is rigorous selection criteria in order for a patient to qualify for a day case knee replacement. More complex cases will usually mean a longer hospital stay, but there are other reasons why someone might not be selected for day case surgery. Whilst age specifically is not a factor, they need to be in general good health and have sufficient support at home during the recovery period.

Think you may need surgery? Learn how to spot the signs you need a knee replacement in our blog.

Reducing pressure on the NHS

Day case treatment also reduces the overheads and staffing resource needed for each patient. If we can do more day cases we can treat more people.

Top level modelling by The Kings Fund shows “by treating more patients as day cases, the NHS had in effect saved around £2 billion”6 between 1998 and 2013. This means more resource can be invested elsewhere in the health system in order to benefit other patients.

Reducing knee surgery waiting lists

Following the pandemic, reports show that the total hospital waiting list for treatment on the NHS has hit a record 6 million7. The positive knock-on effect of discharging patients early is that beds become free for other patients. This leads to more patients being seen thus reducing the waitlist for those in need, whether that is privately, or on the NHS.

Ensuring positive outcomes

The key to successful day case surgeries is:

  • careful selection criteria
  • ongoing support once the patient is home.

GIRFT8 have been driving change and promoting the benefits of day case surgery in all specialities. The vision is that the average length of stay in non-day case joint surgery should be 48 hours. This will achieve better outcomes for our patients.

Practice Plus Group are working hard to make this a reality. Our Practice Plus Group Hospital in Ilford currently achieves an average length of stay of 40 hours for all joint replacements.


1 Surgeon Profile
2 NHS conditions – hip replacement
3 CKS Nice – osteoarthritis
4 Getting it right first time – National Day Surgery Delivery Pack PDF
6 Kings Fund – Day case surgery
7 Royal College of Surgeons press release – waiting times
8 Getting it right first time