Knee endoprosthesis: complications due to too many kilos
Overweight patients with a knee endoprosthesis are at an increased risk of complications from a body mass index (BMI) of about 30. They often suffer from wound healing disorders and infections and need to be re-operated more often. From a BMI of 40, the risk of complications increases exponentially. Therefore, the AE - German Society of Endoprosthetics recommends to reduce the body weight for planned prosthesis implantation as long as possible before the procedure. Even better, however, would be to maintain normal weight throughout life, according to the AE. Because too many kilos are one of the main causes of painful arthrosis of the knee joint. Patients are often unaware of this relationship.
Every year around 169,000 knee endoprosthesis are used in Germany. Some of these interventions could be prevented by losing weight. Because: "Being overweight on the knee joints and is one of the main reasons for osteoarthritis," says Prof. Dr. med. Karl-Dieter Heller, Secretary General of the AE and chief physician of the Orthopedic Clinic at the Duchess Elisabeth Hospital in Braunschweig. In addition, the higher the BMI, the faster the painful joint wear progresses. "In overweight, knee osteoarthritis often occurs at a young age," says the specialist in orthopedics and trauma surgery. Even five kilos overweight doubled the risk of developing knee arthrosis, in which the cartilage in the joint wears off.
Over 65 percent of men and more than 50 percent of women between the ages of 18 and 79 are overweight in Germany, according to figures from the Robert Koch Institute. Obesity refers to a BMI of over 25 - that is, a body weight of more than 25 kg / m2 - as obese, who has a BMI over 30. A quarter of adults are obese. The proportion of overweight and obese patients who receive a knee endoprosthesis also increases accordingly. But with the fullness of the body also increases the risk of surgery: "Obesity is often associated with multiple diseases, such as cardiovascular problems in combination with diabetes," says Heller. These underlying diseases weaken the organism and make it more susceptible to complications such as infections. In addition, operative access to the joint, ie the incision size and depth, is greater in the case of obesity and the situation is more confusing. "The precision of the surgical procedure may be impaired," says Heller. A particularly common and lengthy complication are wound healing disorders: "The fat layer is less well supplied with blood and thus also the overlying skin. As a result, the wound edges are undersupplied and can die, so that the wound may no longer close - the breeding ground for infections is thus laid, "Heller continues.
"We therefore recommend our patients to lose weight before a planned prosthetic surgery and do something for general fitness," says Prof. Dr. med. Florian Gebhard, President of the AE and Medical Director of the Department of Trauma, Hand, Plastic and Reconstructive Surgery at the University Hospital Ulm. For untrained obese are very suitable as electric bikes. They protect the joints and help with hills and longer distances. And he adds, "We also advise keeping the new weight for a while before surgery." Because in the phase of losing weight, the risk of complications is also increased.
Despite the risks mentioned above, overweight patients up to a BMI of about 40 benefit from a knee endoprosthesis. "But before that, all conservative options, such as physiotherapy and pain therapy, must be exhausted," emphasizes Heller. Only after that, together with the patient, the pros and cons of an operation should be carefully weighed. If a knee endoprosthesis is unavoidable, Heller advises all, but especially strongly obese patients to go for the procedure in a certified endoprosthetics center (EndoCert certification of the German Society of Orthopedics and Orthopedic Surgery (DGOOC)). And if the surgery is over, it is one of the homework of the patient, the weight regularly to control and stay active: Because the artificial joint benefits from less kilos and well-trained muscles.