The personalKNEE Trial

Robotic knee surgery makes it possible to adopt different alignment philosophies in total knee arthroplasty. The classical operation where the knee is placed in a neutral manner, the so called mechanical alignment, has been used for decades. The kinematical alignment has recently won popularity. With this technique the focus is to render the natural knee anatomy even if this means to end up with a varus or valgus position. In this study, the investigators will compare the mechanical alignment and kinematical alignment and test the patients clinically and with a special CT scan to see if this technique gives equal or better longevity of the implants.

Inclusion Criteria: • femoro-tibial or patello-femoral osteoarthritis (Kellgren-Lawrence, K-L) grade 2-4 with persistent pain, referred to Kristiansund Hospital for primary TKA Exclusion Criteria: * serious psychiatric disorders * dementia * drug abuse * patients not able to speak and read Norwegian language making them noncompliant or unable to perform an informed consent * Patients with ongoing cancer therapy * Patients with ASA (The American Society of Anesthesiologists physical status class risk stratification system) classification \>3 * Patients in the need of walking aid devices * Patients in need of primary revision arthroplasty or more than 15 degrees of varus or 5 degrees of valgus on preoperative HKA images.