The objective of this clinical trial is to verify the effectiveness of polyvinyl pyrrolidone collagen in all patients with symptomatic gonarthrosis grades II-IV in patients over 40 years of age. The main objectives that this study aims to answer are the following:

1. - Document the effectiveness of intra-articular polyvinylpyrrolidone collagen in the treatment of symptomatic gonarthrosis.
2. - Compare the intensity of pain, the degree of stiffness and functionality of the joint, prior to application and one month after the therapeutic intervention.
3. - Identify demographic, clinical and therapeutic factors that influence the effectiveness of intra-articular PVP collagen in the treatment of symptomatic gonarthrosis.

Patients diagnosed with symptomatic gonarthrosis Grade II-IV, referred to the Physical Medicine and Rehabilitation service within 3 months, will be selected. Two study groups will be assigned: GROUP those who received intra-articular infiltration of PVP Collagen, GROUP B: patients who received conservative treatment. Through rehabilitation with a home program for one month, in both cases, ENA and the WOMAC scale will be evaluated at the beginning of the study and after 4 weeks.

INTRODUCTION: Osteoarthritis is a disorder characterized by progressive deterioration of cartilage in synovial joints, affecting more than 55% of the elderly population, causing significant physical disability, implying a great challenge in medical treatment.

MATERIAL AND METHODS: A sequential, simple randomized clinical trial was carried out in patients diagnosed with symptomatic gonarthrosis Grade II-IV, referred to the Physical Medicine and Rehabilitation service in 3 months, through two study groups: GROUP Those who received intra-articular infiltration of Collagen PVP, GROUP B: patients who received conservative treatment through rehabilitation with a home program for one month. In both cases, ENA and the WOMAC scale were evaluated at the beginning of the study and at 4 weeks.

Inclusion Criteria:

1. Age over 40 years.
2. Both sexes.
3. Joint stiffness less than 30 minutes.
4. Crepitus in the knee joint.
5. Pain in one or both knees lasting more than three months.
6. Continuous pain Quantified in >5 Analog Numerical Scale.
7. Patients entitled to the Mexican Social Security Institute.
8. Radiological criteria for gonarthrosis in phases II, III, IV.
9. Patients not candidates for surgical treatment.

Exclusion Criteria:

1. Rheumatoid arthritis, gout or chondrocalcinosis.
2. Treatment with glucosamine, chondroitin, diacerein, silver non-saponifiables or slow-acting drug in the last three months.

4. Anticoagulant treatment. 5. Paget's disease. 6. Treatment with viscosupplementation in the last six months. 7. Patients not entitled to the Mexican Social Security Institute.