Knee replacement surgery is also known as knee arthroscopy and is used to repair, restore and relieve severely diseased knee joints. The knees carry the brunt of the body’s weight and due to ageing or osteoarthritis, these joints may become eroded and inflamed leading to severe pain and limitation of movement; activities like walking, climbing stairs and getting in and out of chairs become difficult. The purpose of total knee replacement is to use artificial materials to repair and create a new knee joint that would give back the knees their ability to roll and glide effortlessly again.
In the earlier days, knee joints were little more than just crude hinge joints, but with time, this procedure has become very refined and the doctors and patients can now choose from a variety of materials and designs to suit the patient’s age, weight, health and overall activity level.
During the procedure, the surgeon cuts off the damaged bone and cartilage from the lower head of the thigh bone, upper head of the shin bone as well as the knees; he then replaces it with artificial joint parts made with metal alloys, high grade plastics and polymers and glues them with a special gum. Recovery can take anytime from 3 months to one year, depending on the person’s age and health.
As with all surgeries, total knee replacement (TKR) surgery also comes with its own share of risks and serious complications can occur in 2% of the cases. Before heading for the operating theater, the patient needs to know that there is a 30-day mortality rate for those opting for TKR surgery and occurs in 1 out of every 400 cases (0.25%)….which also means that 99.75% survive the surgery! Let’s take a look at some of the complication factors:
Infections – Though all the materials and prosthetic parts are sterilized prior to commencing surgery, infection can set into the newly replaced joint; in such cases, the joint is removed and replaced with a new one during a second surgery after the infection has cleared.
Blood clots – Surgery of any kind stimulates the clotting process and clots can form in the leg vessels (DVT) or the lungs (PE), within a few hours after surgery to within two weeks. Some of these clots can prove fatal when lodged in the heart or lungs.
Nerve damage – These can occur during surgery but improve with time.
Joint failure – In rare cases there may be a malfunction in the prosthesis or improper placement; it could also become loosened. In some cases, presence of scar tissue or Baker’s cyst may limit proper functioning of the joint and require a follow-up procedure for correction.
In extremely rare cases, there may be an allergic reaction to some parts of the prosthesis which are usually made of titanium or cobalt-chromium alloys. Equally rare are cases where metal or plastic fragments break off and enter the circulation, causing inflammation.
As risks are extremely lower than benefits, knee replacements can be considered as boons.
