Total Knee Replacement Surgery
What is involved?
A total knee replacement is a procedure that involves replacing both sides of the knee joint (femur and tibia). If the cartilage within the knee has become worn or eroded due to either arthritis or another pathology, it will lead to pain and swelling within the joint. A total knee replacement can be performed to improve the range of movement and reduce the pain within your knee. The knee joint is opened and specialised instruments are used to remove the worn out surfaces of the tibia and femur. The bony cuts are made in such a way as to allow any deformity within your knee joint to be corrected, and an implant to be placed within the knee joint. The ends of the bone are resurfaced with metal attached to your bone using a special cement. In between the two metal components a highly specialised plastic bearing is fitted, to then allow the prosthesis to move smoothly and the joint to bend, straighten and twist like a normal knee.
The procedure is normally carried out under a spinal anaesthetic where your legs are numb. This can be combined with various levels of sedation to ensure you are either fully awake during the surgery or have no recollection of it. The spinal anaesthetic will also help with pain control immediately following surgery.
Why might I need a knee replacement?
A knee replacement is a procedure to allow the knee to move in a pain-free and smooth fashion. It may be required if you have a degenerative condition, such as osteoarthritis or rheumatoid arthritis, affecting your knee joint, or in certain instances a significant injury to the knee can mean require a knee replacement.
What happens after surgery?
We are committed to ensuring our patients have the most up-to-date and efficient post-operative rehabilitation. We use Hilotherm cold water therapy; when you are transferred back to the ward, your knee will be wrapped in a specialised cooling device which provides compression and the circulation of cold water circumferentially around the knee, to reduce pain and swelling. You will be offered pain killers and the nursing staff will take regular observations. Once you have fully recovered from the anaesthetic, our expert physiotherapy team will get you up and walking on the day of surgery. You will be able to bear your full weight through the replaced knee immediately, as early mobilisation, with the assistance of crutches or sticks, has been shown to reduce pain, lower the risks of blood clots, and improve your outcome in the long term.
Your leg may be swollen and bruised, so continued ice therapy and elevation is useful in the days following knee replacement surgery to reduce this. You will have an x-ray of your new knee replacement on the day of surgery, which will be checked by the surgical team prior to your discharge. The average length of stay following a knee replacement is between one and four nights, depending on your medical comorbidities (other medical conditions) and your personal preferences. Following discharge your surgeon will arrange to see you two to three weeks after surgery to check your wound and ensure you are progressing as planned.
Recovery milestones
Days 1 to 4: Over this period of time you will take regular pain killers and have regular physiotherapy. Once you are safe on your feet and would like to go home, you will be discharged by the physiotherapy team.
Weeks 1 to 2: Over this period of time the swelling and bruising will gradually subside in your knee. You must keep the dressing on at all times to maintain the sterile environment around the knee wound and allow it to heal. If the dressing becomes soaked through with blood and leaks, our expert ward team will see you to re-dress it in an appropriate fashion. Rest, ice and elevation, as well as gently bending and straightening the knee, will ensure it settles down and you achieve good results.
Weeks 2 to 12: Over this period of time your range of movement will continue to improve. You may occasionally find the knee swells and becomes uncomfortable if you do a lot of walking, but this is nothing to be worried about. Gradually your physiotherapists will work with you to improve the strength around your knee and you will find you’ll be able to walk longer distances over time.
Months 3 to 18: Recovery from a knee replacement is long and requires patience. Over a period of up to 18 months the soft tissues around your knee will settle and soften, and your knee will feel more and more natural over this period of time. It is not unusual for there to be good days and bad days, so be patient.
Frequently asked questions
How is the wound closed?
You will have a straight wound over the front of your knee between 15cm and 30cm long. This can be closed with either metal clips or dissolving stitches. Please ask your surgeon what their preference is, as it varies in each case.
When can I start to drive again?
There will be no damage to your knee replacement if you start driving, however, the DVLA state that it is the responsibility of the driver to ensure they are always in control of their vehicle. In reality when you feel you can press down hard enough to perform an emergency stop with the operated leg, this is a good indicator of when you could start driving. Recent research has indicated that on average this is between four to six weeks after surgery. It is advisable to notify your insurer that you have had surgery and intend to start driving again.
When can I return to work?
This depends on the type of work you do and whether or not you have a long commute. As a rough guide, if you have an office-based job, you could return to work after approximately six weeks, but if your job involves manual work, it may be more like three to four months.
Can I kneel after a knee replacement?
Yes. There are no restrictions to your ability to kneel after having had a knee replacement. Approximately 30 per cent of patients, however, find it too uncomfortable to do so following knee replacement surgery, and this is normally related to the level of discomfort you might have had in kneeling prior to the operation.
When can I return to sports?
Returning to sports generally depends on how quickly you recover after your surgery, and the complexity of your knee replacement operation. It is advisable not to return to sport until you have adequate flexibility, strength and fitness, as you can incur further injury if you return too soon. It is realistic to expect to get back to activities that do not place too much strain on the knee joint, such as walking, cycling, golf, bowls, hiking and swimming. However, more active sports, such as football, squash and skiing, can be difficult after a knee replacement. Talk to your surgeon about your specific case, and whether it is advisable to return to these activities.
Will my knee replacement set off airport metal detectors?
In most instances metal joint replacements do set off airport security alarms, and it is advisable to take evidence of your surgery with you when travelling. However, on most occasions, if you show the airport staff your scar, they will accept this as evidence.
How long does a knee replacement last?
Advances are being made in arthroplasty surgery all the time. We currently have much more sophisticated plastic-bearing surfaces available in comparison to those that were used in the past. Wear of this plastic bearing was the most common reason for knee replacements requiring revision. It is therefore likely that the knee replacements we are putting in today will last longer than those put in previously. As a rough estimate we would hope that your knee replacement would last at least 15 to 25 years.
