Secondary outcome measures include: Pain evaluation with the use of VAS at rest, VAS on walking and on knee flexion; functional outcome evaluation with the 6 min walk tests, degree of knee flexion, Scores obtained in self-assessment questionaire (WOMAC-Western Ontario and McMaster University questionaire for knee osteoarthritis and CHAMPS-Community Healthy Activities Model Program for Seniors). These values will be compared with baseline values recorded before surgery.