Inclusion Criteria:  age between 55 and 85 years inclusive, Normal weight patients with BMI 18-24.9 included Obese patients with BMI ≥ 30 Patients with gonarthrosis awaiting knee replacement surgery Patients awaiting knee replacement surgery Patients who agree to sign informed consent  Exclusion Criteria:  Patients less than 55 years of age. Patients over 85 years of age Patients with diabetes mellitus Patients who are unable to understand and want Patients with severe neurological disorders or with severe disabilities Rheumatoid arthritis patients Cancer patients Patients on immunosuppressive therapy