Replacing the knee joint with a prostheses, or artificial joint may cause problems. The long term complications of knee replacements can vary according to the individual, the type of surgery performed and the prostheses itself. The immediate complications right after surgery could intensify and get worse. The quality of the recovery after surgery, in terms of the mobility regained, and quality of life could affect the long term. Additional disease or injury can happen. The person’s age and gender can affect the outcome. Gait or movement disorders may become evident as the artificial knee affects the other parts of the body like the hips.
Arthroplasty in the knee, or the shaping of a joint, has developed over the years. The first knee replacement was performed in 1968; surgical techniques and outcomes have changed and improved. The degree of trauma to the body varies, such as the size of the incision, the ligaments and tendons severed. Minimally invasive techniques that reduce trauma can have better long term outcomes, as the body does not have as much work to heal. Movement may be more natural and reduce negative effects on other body parts and structures. The degree of initial trauma to the knee during surgery will affect the future.
Recovery After Surgery
Recovery after the initial surgery should be as complete as possible to restore function, range of motion and a normal active life. Incomplete recovery can lock the knee’s function with scar tissue, affect the other knee, hips and spine. Pain management is the major goal of knee replacement initially and if this does not occur, long term pain can be expected. Recovery should include restoration of range of motion, a variety of low-impact exercise, avoidance of harmful recreational or work related activities, weight management, proper nutrition to lubricate the joint, and other therapies like acupunture.
Complications immediately after surgery such as deep vein thrombosis, bleeding, infection, pain in the hips and back may worsen over time. Having two knees replaced at the same time could prove a heavy burden for the body to bear. Medical conditions such as diabetes can affect the whole body and adversely affect the knee. A person’s genetics, age, physical condition and gender may complicate matters as well.
The prostheses design and it’s lifespan varies and it may malfunction. An artificial joint can last 10-15 years, with 85 percent lasting 20 years. Prostheses are made from ceramic, plastic and metal or a combination. Zirconia and carbon are new materials currently being tested with the hope of having longer lifespans and less malfunction. These newer materials have not been around long enough to know their long term benefits or disadvantages. Cementing methods, adhering the artificial joint to the natural bone, vary as well and have improved. Their long term effects are not known yet.
A person’s age can affect the long term complications of knee replacements. A person in their fifties could expect the joint to wear out in 10-20 years, making it necessary to replace the joint again in their sixties or seventies. With the average lifespan increasing, a person could get three knee replacements if they start too young. Each additional surgery of any type increases complications. Lifestyle changes are advised to those considered too young for surgery.
Revision Surgery Reasons
Each year, an estimated twenty thousand knee revision (correction) surgeries are performed. The reasons for these are mainly:
prostheses: material failure, loosening, malalignment, mechanical failure.
body: joint instability, infection, tissue death, bone fracture, and patellar damage.