What are knee replacements?
Knee replacement surgery, also called knee arthroplasty, is a common orthopaedic procedure in Singapore. Knee replacement surgery can help to relieve pain in knee joints as well as help restore function in knee joints that are severely damaged or diseased.
During a knee replacement surgery, tissue and bone around the knee joint are removed and replaced with a new implant which can help you to retain the function of a healthy knee. The procedure usually involves removing damaged bone, cartilage, and tissues within one knee joint, and replacing it with an artificial implant (prosthesis), made out of metal alloys, polymers, and high-grade plastics.
Partial knee replacements, also known as unicompartmental knee replacements, are a subset of knee replacement surgeries. In partial knee replacements, the orthopaedic surgeon removes damaged tissue and bone in one part of the knee while the rest of the knee is preserved. These surgeries are often done with smaller incisions over the skin, thereby allowing recovery time to be shorter, smoother, and with a lower risk of complications such as bleeding, infection, and pain.
Why do people undergo partial knee replacement surgery?
The two main purposes of partial knee replacement (i.e. using a relatively tiny artificial implant known as a prosthesis to replace the medial compartment of your knee joint) are as follows:
Relief of knee pain, stiffness and other symptoms
The most common reason people have for going through partial knee replacement surgery is to ease pain from osteoarthritis, which gets quite severe as the disease progresses. Osteoarthritis is a prevalent disease seen in the elderly as it is a form of degenerative change that happens to our joints as we age. Patients will often complain of pain, stiffness, and swelling of a joint when it is affected by arthritis, and this can lead to discomfort and pain, which often interferes with daily life. Thankfully, partial knee replacement can often alleviate these symptoms by addressing the root cause of the problem.
Boost in quality of life
Another reason for choosing to go under the knife is to enhance joint functionality (or preserve and maintain overall knee function), potentially widening the range of activities available to the individual. Often, patients may be recommended for knee replacement surgery if their symptoms hamper their daily life. This can include having pain so severe they are unable to sleep soundly through the night, and knee pain that prevents them from doing daily activities. Fortunately, partial knee replacements provide various enhancements that will restore your knee’s function and maintain a natural feeling when moving the knee. It has been proven to be more effective in increasing knee range of movement and providing a more natural-feeling knee when compared to total knee replacement. A high percentage of patients are even able to go back to the sporting activities that they love, gradually.
As with any operation, there are still some plausible risks, such as infection, loosening of the implant and bone fracture around the implant, although these are rare.
Who gets the most out of a knee replacement?
Most people who do knee replacement are around their middle age or age 60 years and older. Partial knee replacements are a good choice in patients who not recovering well despite non-surgical treatments and only have arthritic changes in one part/side of the knee. Implants will only cover these damaged areas, and the rest of the normal knee joint tissue will be retained.
The operation is rarely complicated, and recovery time is usually fast as well. With a knee replacement, patients will benefit from less pain and stiffness in their knee joint and will be able to walk more comfortably again.
What happens before, during and after a knee replacement?
Pre-surgery preparations
Your orthopaedic surgeon will usually assess your need for a knee replacement during a clinic visit. This will involve taking a history, physical examination, and tests like X-rays to assess the health of the knee joint and look for any areas of damage. If damage is present to more than one part of the knee, you may need a total knee replacement.
Before the operation, you will be seen by an anaesthetist as the procedure is usually done under anaesthesia. The anaesthesia given during partial knee replacement will either be general anaesthesia (where patients are asleep throughout the procedure) or regional anaesthesia (where patients will be numb from the waist down, but will be given medications to help them to relax or feel sleepy). The anaesthetist will assess your suitability for anaesthesia and whether or not you are fit for surgery and may advise you on certain things before the operation (e.g. to stop smoking for several weeks beforehand, to stop taking blood thinners a few days before the operation, etc).
Surgical process
Knee operations are usually around 2-3 hours long, and patients tend to recover quickly. During the operation itself, once you are under anaesthesia, the orthopaedic surgeon will begin by making a cut along your knee. The incisions are usually a few inches long. The surgeon will inspect the knee joint and slowly remove the damaged bone and tissue. Once the tissues are removed, the implant will then be put in its place and attached with bone cement. The wound will then be closed with stitches.
Post-surgery
If there are no complications, you may be able to go home within 1-2 days after the procedure, and patients can usually put their full weight on the knee right away. However, walking comfortably on the implant may take a few weeks. High-impact activities like jogging should be avoided for a few weeks after the operation.
After discharge, you may be prescribed painkillers in addition to home leave for a few weeks after the operation to allow you time to recover. For some patients, physical therapy may also be advisable to help improve the range of motion around their new knee joint and strengthen the muscles around the knee. This is usually for cases with long-standing damage and deterioration to both the knee joint and the muscles around it. Physiotherapy can help to improve mobility and function as well as reduce pain overall.
Overall, most patients recover quickly after knee replacements and have much less pain than before surgery. Patients who have had partial knee replacements typically recover faster than those with a total knee replacement.
How does a Partial Knee Replacement offer faster recovery?
Since the surgery involves one side of your knee, the Unicompartmental Knee Replacement Surgery alleviates arthritis pain in the affected or damaged section of your knee while preserving the remaining joint surfaces. Due to the less invasive nature of the surgery, there is a shorter hospital stay and faster recovery.
Visit Oxford Orthopaedics for tailored advice
This blog article provides general information everyone considering partial knee replacement should know. For personalised advice from an esteemed and experienced orthopaedic surgeon, please schedule an appointment with Oxford Orthopaedics. Oxford Orthopaedics is a specialist centre conveniently located at Singapore’s Mt Elizabeth Hospital, Mt Alvernia Hospital, and Farrer Park Hospital. Our friendly staff will be happy to help you book a consultation with Senior Consultant Orthopaedic Surgeon Dr James Wee, who has close to 20 years of clinical experience.