The aim of this study is to evaluate the efficacy and safety of Hymovis® ONE (32 mg/4 ml) single intra-articular injection, in the management of pain caused by knee osteochondral lesions.

There are no studies in literature up to now, that analyze the changes in knee pain and correlate this parameter with knee function and biomechanics, in regular casual sport player subject affected by knee overuse syndrome and underwent an intra-articular HA injection. The aim of this study is to evaluate efficacy and safety of Hymovis® ONE (32 mg/4 ml) single intra-articular injection, in the management of pain caused by knee osteochondral lesions.

Inclusion Criteria:

1. Male or female higher than 18 and less or equal to 65 years of age
2. an active life-style, professional or regular casual sport player (people who plays sport or trains themselves at least 2-3 times per week).
3. diagnosis of knee osteoarthritis will be based upon a standing weight bearing knee X-ray at Screening or an X-ray performed within 6 months prior to screening. The radiograms must be classified as a Kellgren and Lawrence Grade I-III for osteoarthritis of the knee.
4. a knee VAS pain score, within 48 hours before the visit.
5. patients must have had all analgesic/anti-inflammatory drugs discontinued for 2 weeks prior to Baseline except for acetaminophen.

Exclusion Criteria:

1. Major injury to the contralateral knee or other weight-bearing joint if it would interfere with the study assessments.
2. Surgical procedure of the studied joint within the previous 12 months prior to Screening.
3. Ligament reconstruction in the target knee within 1 year
4. Inflammatory arthropathies such as rheumatoid arthritis, lupus, or psoriatic arthritis
5. Intra-articular or local peri-articular corticosteroid injections to the study joint/knee within the previous 3 months prior to screening or to any other joint (beside the study joint) or soft tissue area within the previous month prior to Screening.
6. Any corticosteroid within the previous month. Steroid inhalants are permitted if the patient has been on a stable regimen for the past month prior to Screening and remains on this regimen throughout the course of the trial.
7. Intra-articular hyaluronan in the studied joint within the previous 6 months prior to Screening.
8. History of allergic reaction to an intra-articular Hyaluronic acid injection
9. Use of glucosamine- or chondroitin sulfate-containing products unless the patient is on stable doses for at least 4 months prior to Screening and willing to remain on these stable doses throughout the course of the trial.
10. Patients with X-ray findings of acute fractures, severe loss of bone density, avascular necrosis and/or severe deformity.
11. Axial deviation of the lower limbs higher than 20 degrees in valgus or varus on standing X-ray.
12. Symptomatic osteoarthritis of either hip, contralateral knee or spine that may interfere with functional assessment of the signal knee.
13. Clinically significant medio-lateral and/or anterior-posterior instability.
14. Osteonecrosis of either knee.
15. If patients are receiving or performing physical therapy at Screening, this physical therapy regimen has not been stable during the one-month preceding Screening and the patient is not willing to maintain the same regimen throughout the course of the trial.
16. Patients with Kellgren-Lawrence Stage IV osteoarthritis of the knee (i.e.,in grade IV large osteophytes, marked narrowing, severe sclerosis, and definite deformity).
17. Hemiparesis of the lower limbs