Autologous chondrocyte implant (ACI) is a very effective technique in the treatment of chondral lesions in order to restore normal hyaline cartilage. This technique, reported for the first time by Peterson in 1994, is advised for young or middle-aged. active patients with a single painful chondral injury (3/4 grade of Outerbridge scale), starting from more than 2 cm². New tissue engineering techniques with the use of biomaterial derived from hyaluronic acid (HYAFF matrix) provide ideal support for the culture and proliferation of chondrocytes, allowing at the same time arthroscopic implant. There are many advantages of arthroscopic techniques: easy implant and less pain post-operatively; however, the indications for arthroscopic technique are still restricted: single chondral inury, 2–6 cm² in size and localisation at the femoral condyles.

At the Department of Orthopaedic Surgery of the University “ Federico II ” of Naples starting from January 1996 to the present, 29 patients were treated with ACI. Eight patients (six men and two women) had an arthroscopic implant. Median age was 18; in seven patients an OCD of the medial femoral condyle was present and just one patient had a post-traumatic injury of the medial femoral condyle. Hyalograft was used in all cases. All patients underwent CPM starting from the second post-operative day and full charge was allowed after 2 months. All patients were evaluated by clinical examination with IKDC score and functional score (Tegner) at 3, 6 and 12 months after surgery and with a MNR at 6 and 12 months after surgery and then every year.

Good results were found subjectively in 88% of the patients, with a complete lack of pain in 70% cases. Using the IKDC score good results were found in 85% of the cases (average score 90). With the Tegner score we reported an improvement in the level of activity in 60% of the cases.

The MNR images, performed with standard sequences, fat-suppressed and in the last cases with dGEMRIC, showed the presence of regeneration tissue inside the chondral defects, with a signal very similar to that of the cartilage tissue, sometimes slightly deeper.

Our experience shows that ACI is an effective way of treating chondral lesions with excellent results. We think that progress in the field of biomaterials will extend the indications for arthroscopic techniques, also allowing implants in larger lesions and at other sites.

The authors present their experience with high tibial osteotomy for the correction of varus knee, performed wih an open wedge technique (Puddu). This technique allows correction of varus knee with a medial tibial osteotomy open wedge, using a special tibial plate; this plate is fixed with two cortical screws and two spongious screws and is formed by a tooth that prevents the correction from loosening. The aim of our work is the retrospective clinical and radiographic evaluation of 18 patients treated with Puddu technique at the University of Naples.

Indications for this technique are: constitutional varus knee, chondral damage after medial meniscectomy and medial gonarthrosis. From June 1999 to the present we treated 18 patients (13 women, five men), median age 54, with high tibial osteotomy with Puddu technique at the department of Orthopaedics and Traumatology of the University of Naples. Before the osteotomy we normally perform a knee arthroscopy to achieve a correct articular balance (evaluation of articular cartilage, menisci and ligaments) and to treat associated lesions. All patients were evaluated by clinical examination with IKDC score and X-rays. Median follow-up was 30 months.

Results are very good with an important improvement in pain and disability. Vascular and neurological complications were not found in any of the patients; all the osteotomies had a strong consolidation and showed good correction of the deformity.

High tibial osteotomy with Puddu technique in our opinion seems to be an effective technique in the treatment of medial knee arthritis and in the correction of femoral-tibial axis. It is an easy, reproducible and trusted technique and in our opinion recommended over the traditional tibial osteotomies (closed wedge osteotomy, dome osteotomy and osteotomy with external fixation, etc).