When osteoarthritis has reached a clinical stage with severe musculoskeletal pain, prosthetic replacement of the joint may become necessary. There are two main types of knee-replacement techniques: total knee replacement (TKA, total knee arthroplasty) and partial knee replacement (UKA, unicompartmental knee arthroplasty / uni-prosthesis surgery). There are also different types of prostheses. The kind of prosthesis that is most suitable depends on several factors such as the nature of the damage, patient weight, knee size etc.

Some patients only suffer from lesions on the inside of the knee joint. In those cases a uni-prosthesis can replace the inner joint surfaces only and a partial knee replacement is performed. This is primarily done on patients between 60 and 70 years of age. Patients with severely deteriorated knee joints need to undergo total knee-replacement surgery.

For most patients, the results of knee replacement surgeries are very satisfying. The purposes of these surgeries are to eliminate pain and increase the quality of everyday life. A knee prosthesis is, however, not a natural joint. Patients cannot expect to perform intensive exercise or engage in activities that put excessive stress on a replaced knee joint.

Image: an Episealer implant compared to a total knee prosthesis

Prosthetic knee joint replacements require the removal of large amounts of the patient’s bone prior to the implantation of the prosthesis. The rehabilitation period is rather long, often 6-12 months. The estimated life-time of a knee prosthesis is generally alleged to be up to 20 years. For young individuals, prostheses are less suitable, since they would need to be replaced during the patients’ life-time. The replacement of a worn-out prosthesis is a risky procedure and the rehabilitation is often difficult, therefore doctors generally try to delay knee replacement surgery as long as possible. As a result, there is a reluctance to offer patients younger than 65 years knee-replacement surgery.