There are so many questions that a patient begins to ask before undergoing knee replacement surgery. Knee arthroplasty is one of the most frequently performed orthopedic surgeries: about 85,000 prostheses are implanted in Italy each year. This occurs because, the prosthesis by knee, is one of the most successful interventions and the only solution that can ensure functional recovery as well as the disappearance of joint pain whenarthrosis has now worn away the cartilage.
Despite this, patients turn out, often, to be very concerned about this type of surgery, both before and after the operation. In reality, thanks to improved prosthetic designs, increasingly biocompatible and durable materials, and minimally invasive surgical techniques, clinical results are, to date, truly excellent.
To reassure those who are about to undergo this surgery, I decided to answer the most frequently asked questions that come to us orthopedic surgeons.
When is knee replacement surgery necessary?
Whencartilage wear is such that it makes daily activities difficult and causes pain, knee replacement should be considered. Knee replacement surgery, in fact, by replacing the suffering and nonfunctional joint, allows people to return to their activities without pain and thus regain full mobility.
At what age is it advisable to undergo the surgery?
Improved materials and long-term clinical outcomes have made it possible to extend the surgical indication to relatively young patients who have not found benefit from infiltrative therapies or nonprosthetic surgeries such as osteotomy and/or meniscus allograft transplantation. There is, therefore, no inadvisable age at which to undergo surgery.
How can I avoid knee arthroplasty?
Certainly a radical change in one’s lifestyle (such as may be weight loss), or undergoing specific physical therapies can help manage problems related to cartilage wear and tear and relieve knee pain. Recent studies have shown that sports such as swimming or yoga improve motility and pain in the knee.
All of this, however, is not a final resolution of the problem; in fact, postponing the surgery could make the situation worse: loss of muscles, deviation of the knee axis, and chronic joint inflammation are just some of the problems associated with continuing the pathological condition ofknee osteoarthritis.
It is always best to consult a specialist who will evaluate the specific case.
Are there knee replacements specifically for women?
Yes! Increasingly accurate tests on patients have led to the production of so-called gender prostheses, specifically designed to more functionally match a woman’s specific conformation at the femoral level.
What are the risks of surgery?
Keeping in mind that most surgeries end without complications, it is good to keep in mind that, in rare cases, complications such as infection or thrombophlebitis of the operated limb may occur. To prevent these types of inconveniences, antibiotic and antithrombotic prophylaxis are administered during and after the operation. There are also dangers associated with anesthesia: one should know that any surgery is considered potentially risky; in this regard, anesthesiologists will evaluate on a case-by-case basis whether to perform spinal anesthesia, loco-regional anesthesia, or general anesthesia. Even in the case of non-general anesthesia, the anesthesiologist will administer mild medications so that the patient can sleep and not make him “worry” about what is happening around him.
What materials are used for the prostheses? Could I be allergic to them?
The knee prosthesis is made of metal alloys, specifically an alloy of chromium and cobalt; these materials are biocompatible and have been used successfully for several decades. THE EXISTENCE OF HYPERSENSIVITY (allergy) TO METALS prosthetics has been debated for many years. However, if the Patient reports in history intolerance or allergy to materials such as Nickel (such as skin reactions from costume jewelry), a hypoallergenic prosthesis made of Titanium alloy or ceramic alloy (Oxinium) will be implanted. Skin allergy tests do not appear to be reliable studies and therefore are not applied as screening.
A special plastic material (polyethylene) is then used, interposed between the two metal surfaces for the purpose of facilitating sliding(prosthetic insert). Since 2000, high-molecular-weight polyethylene (UHMWPE) used in knee prosthetics has documented a very low wear rate, making it plausible that the knee prosthesis will last well over 20 years.
What is the recovery time after knee replacement surgery?
As early as the day after surgery, it will be possible to mobilize the knee, starting to take the first steps. In order to resume normal daily activities (without the use of crutches), however, it will be necessary to wait a period varying between 3 and 5 weeks; we expect that, within 4 months, the patient will be able to resume sports.
How to sleep with knee replacement?
There is no limitation in the positions in which one prefers to sleep; however, one must absolutely avoid placing the pillow under the operated knee for a long time during the first few days: knee extension is of primary importance for the proper functioning of the joint.
Which sports are recommended and which should be avoided?
After surgery, it is recommended to perform activities such as walking, exercise biking and swimming that promote the resumption of movement without burdening the knee; contact sports (soccer, basketball), however, should be avoided. Recent articles have documented that continuous ground impact activities such as running, once discouraged, do not change the life of the knee replacement. Upon reaching full recovery, if the physique allows, sports such as skiing and tennis.
Can knee replacement activate airport warning system?
This is a possibility, depending on the calibration of airport detectors; after Sept. 11, 2001, documents attesting to implantation are no longer accepted at checkpoints as “passes.” But the simple specific examination with the hand-held metal-detector will enable officials to understand the presence of an implanted synthetic means and subsequent air boarding.
How long does a knee replacement last?
It is safe to say that, to date, knee replacements have a survival rate of about 94% 17 years after surgery from data from the Emilia-Romagna regional registry (R.I.P.O.). Obviously, prostheses have a variable duration that depends on several factors such as the weight of the subject and the activities performed daily. In any case, after normal postoperative visits, it will be advisable to perform routine checkups every two years or so.
Do you have any other questions you would like to ask me about the surgery of knee replacement? Do not hesitate to contact me.
