Knee arthroplasty is a new method of preparing an operation, allowing for a precise adjustment of the endoprosthesis to each patient. So read on about knee arthroplasty and how the implant fits.
Knee arthroplastyis rarely the patient's first choice. The initial symptom of degenerative changes is pain and limited mobility of the joint. Initially, the patient is recommended pharmacotherapy and rehabilitation. The administration of hyaluronic acid, collagen, growth factors and recently stem cells to the knee joint is also very successful. Unfortunately, such treatments do not always bring improvement. Many patients require surgery to replace the natural knee joint with an endoprosthesis. One of the methods used isknee arthroplasty .
Knee arthroplasty: what is it about?
Depending on the severity of the degenerative changes, a partial or total knee arthroplasty may be performed, i.e. a part or the entire joint may be removed. The operation consists in replacing the articular surfaces damaged by the disease with prosthetic elements. Precise removal of the damaged bone is an extremely important moment of the operation, because its final result and correct reconstruction of the so-called the mechanical axis of the limb. If the axis passes exactly through the center of the knee, the forces acting on the implant are evenly distributed. Thanks to this, no part of the artificial joint is overloaded, and therefore not prematurely damaged.
- In the traditional method, bone fragments are cut, simplifying the problem, a bit "by eye". In all patients, the bones are prepared for the procedure in the same way - says Andrzej Kotela, MD, PhD, an orthopedist from the Department of Orthopedics and Traumatology of the Motor Organ at the Clinical Hospital. Baby Jesus in Warsaw. - When using the traditional method, the doctor has at his disposal an X-ray image, in which not all elements of the sick joint are clearly visible. So the surgeon does not know all the details of the procedure when proceeding with the operation.
The premise of modern knee arthroplasty is an individual approach toeach patient. Before the operation, computed tomography or magnetic resonance imaging of three joints is performed - ankle, knee and hip. The obtained photos allow very precise determination of the mechanical axis of the operated limb.
- Even before the procedure, using special computer software, the implant is virtually placed in the patient's leg in the most advantageous way from the point of view of the limb biomechanics. The idea is for the joint to behave like a natural one after the surgery, explains Dr. Kotela.
After computer planning of the operation, the so-called bone measures that can be compared to guides that guide the physician during surgery. In other words, the doctor has at his disposal a type of template that is adapted to the patient's bone. During the operation, after opening the knee joint, a ruler is placed over the patient's bone and it is it that determines the lines, angles and the scope of bone beheading.
Worth knowingHow do degenerative changes in the knee joints occur?
Experts estimate that about 40% of degenerative changes in the knee joints are caused by the aging of the organism. The remaining 60% is the result of overload, contusions and injuries - hard physical work, competitive sports, but also being overweight and obese lead to faster wear of the joints. There are also idiopathic degenerations, i.e. those whose causes cannot be determined.
Knee arthroplasty: the effects of the operation
The benefits of such a knee arthroplasty are primarily the precise reconstruction of the joint axis, less bleeding and simplification of the surgical technique. In addition, computer simulation allows you to precisely select the type of implant to the needs of a specific person. The rest of the procedure is carried out in a typical way. A knee joint implant is placed on the precisely prepared bones. The new physician support system is especially useful when the joint is badly damaged. And this is often the case, for example, in patients with rheumatoid arthritis.