According to epidemiological studies, osteoarthritis accounts for 10–12 % of all cases of musculoskeletal diseases. In the general structure of knee pathology, degenerative diseases make up 57.8 %. The urgency of the problems of gonarthrosis is due to not only its widespread prevalence, but also the high risk of developing knee dysfunction, accompanied by a significant reduction in the quality of life of patients and often leading to partial or permanent disability of patients. Gonarthrosis has significant gender features. Women account for about 70 % of the number of patients, while men had this disease almost 2 times less often, but other data indicate that the incidence of gonarthrosis in men under 60 years of age is higher, and in women it begins to increase after 65 years. Knee replacement is a leading method in the treatment of knee osteoarthritis stages III–IV. The tendency towards an increase in the total number of surgeries leads to an increase in the frequency of complications and unsatisfactory results: according to some authors, from 3.3 to 13.2 % of patients complain of knee replacement outcomes. Studies of long-term complaints after arthroplasty have shown that in addition to pain reduction, some patients had an increase in varus angle when bending the knee while walking but they didn’t mark an improvement in gait parameters compared to preoperative examination. After unilateral total knee arthroplasty, the load patterns of the frontal plane in the operated knee remain pathological in the long run. After knee arthroplasty, there is muscle weakness, and studies have shown changes in all muscles of the lower extremity. Weakening of some muscles led to compensatory strengthening of others. Studies of the effect of preoperative rehabilitation on the outcome of knee arthroplasty have shown its low efficiency. Many studies have studied motor activity of patients after total knee arthroplasty in recent years. Not only gait features, but also movements of the pelvis, trunk and upper extremities are studied. Modern methods of diagnosing spatial oscillations of the body when walking have shown that disorders of body movements — excessive hand movements, pelvic loosening, asymmetrical flexion of the knee joints, etc., after arthroplasty are preserved in patients and restore slowly, and some disorders remain forever. Conclusions. Knee arthroplasty relieves pain, improves quality of life, but according to many authors, patients complain of incomplete restoration of the functionality of the prosthetic limb. According to the researchers, the main cause for incomplete reco-very of gait parameters is the difference in the frontal angles of the knee joint flexion and the difference in the length of the steps. Special training exercises can reduce the asymmetry of the steps, but it is difficult to completely restore the symmetry of the steps within 2 years. Studies of the effect of preoperative rehabilitation on the outcome of knee arthroplasty have shown its low effectiveness.
