Despite the various treatment options available, symptomatic articular cartilage defects continue to represent a therapeutic challenge for knee surgeons. This study has been developed in order to retrospectively evaluate and present long term results, from 5 to 8 years, of PVA-H hydrogel impants ("Cartiva") in the treatment of knee chondral focal defects.Presented are the clinical and MRI evaluation of 18 patients with III and IV degree knee chondral or osteochodral defects treated by PVA-H hydrogel implants. Defects were no larger than 20 mm in diameter. Average age at time of surgery was 54 years. There were 11 male and 7 female patients. A total of 20 implants were implanted, 16 with 10 mm and 4 with 15 mm Cartiva implants. One patient was treated bilaterally. The majority (80%) of surgeries were performed arthroscopically. Patients have been assessed by IKDC, SF36 scores and by MRI imaging.All patients have shown improvement of knee function and knee scores, in many cases over 50 points of IKDC, except three. Of these, the first mantained a rather good quality of life for over 5 years with approximately the same level of functionality she enjoys now, after implant removal and knee replacement during 2008. The second case was a 43 year old female with a post-traumatic chondral defect in a valgus knee. The patient experienced post-op pain: the implant was removed among another institution at 6 months post-op and was converted to OATS. The third case was a 49 year old male with a severe arthritic pre-op knee and may not have been ideal candidate for Cartiva, but was too young for a total knee replacement at the time of operation and, despite a severe knee worsening during the last year that will need in the short future a knee replacement, has, at over 6 years follow-up, an IKDC score of 33.33 from a pre-op of 37.93.5 to 8 yy follow-ups enable us to conclude that the use of PVA-H synthetic implants in knee chondral defects in middle aged patients can guarantee critical knee function improvement and severe pain reduction. Even the patients, that have needed a knee replacement, have well done for the first four-five years. Therefore, this mean that this type of treatment with the correct indications and future implant and instrumentation improvements, already in course, may guarantee a several year period of knee health and active life style.