Introduction: Trabecular metal associated with monob-lock elliptical design represents a valid surgical solution for orthopaedic acetabular reconstructive procedures and second surgery.

Materials and methods: From 1999 to 2004, 61 patients between 45 and 81 years with osteoathritis underwent total hip primary arthroplasties with porous tantalum elliptical cup. We performed clinical evaluation through Harris Hip Score test. Bone-implant interface was studied through radiography with reference to the three Charnley’s areas. Follow-up were performed preoperatively at six months and yearly thereafter.

Results: Clinical results showed high improvement of Harris Hip Score (average preoperatively score was 46, postoperatively 90). Radiographic evaluation revealed a bone apposition to the porous tantalum without radiolucent lines around the acetabular interface. No local (osteolysis) or general (DVT) complication was seen.

Conclusions: Tantalum monoblock elliptical acetabular cup with high volumetric porosity, flexibility and high biocompatibility associated with particular microstructure permits direct apposition of bone, more extensive osseointegration with the maximum bone contact. The trabecular metal cup increases the initial stability helping in the prevention of osteolysis and loosening in a five years follow up.

It is well known that articular cartilage in adults has a limited capacity for self-repair. Numerous methods have been devised to augument its natural healing response, but these methods generally lead to filling of the defect with fibrous tissue or fibrocartilage, which lacks the mechanical characteristics of articular cartilage and fails with time. Tissue engineering combines aspects of cell biology, engineering, material science and surgery to generate new functional tissue and provides an important approach to the repair of articular cartilage lesions and, ultimately, functional success. The purpose of our study was to perform experimental resurfacing of articular cartilage in 18 sheep using different techniques: before implantation in all sheep a full-thickness chondral lesion of medial femoral condyle was created; subsequently, autologous chondrocytes seeded into the matrix were implantd into five sheep; a periosteum flap was implanted in five sheep; and, as source of growth factors, adipocytes by vascular peduncle of Hoffa tissue were implanted in five sheep. The reparative tissue of the chondral lesion was compared with uninjured contralateral knee. The results present the bonding between implantation tissue and host tissue, preservation of phenotypic stability of chondrocytes culture, standard dosage of growth factor secreted by adipocytes and characterisation of the histological properties of reparative tissue, comparing different surgical techniques.

This study was conducted to evaluate the clinical and radiographic results on titanium stems that were similar in design but differed with regard to proximal grit-blasted surface texture with and without a hydroxy-apatite (HA) coating. We evaluated 40 patients who had undergone primary total hip replacement by a postero-lateral approach. The stems, all made of titanium alloy, tapered, grit-blasted, collarless, with anterior-posterior fins, did present some differences: in a group of 20 stems a proximal hydroxyapatite coating (thickness: 50 μm) was implanted; in another group of 20 stems the proximal surface was without HA coating. Clinical and radiographic evaluations were performed pre-operatively at 3, 6 and 12 mounths during the first year; than once for the following years.The mean duration of follow-up was 6 years.

At the final follow-up examination the Harris hip scores in the HA-coated group (mean, 96 points) and non-HA coated group (mean, 94 points) were similar. Bone-remodelling patterns were similar in the groups and the fast bone integration of the HA coated group. In both groups only two cases of aseptic loosening of the stems were found.

After 6 years of follow-up, the clinical and radiographic results among grit-blasted titanium tapered stems with or without Ha coating were perfectly similar. The optimum final bone integration was due just to the singular shape of femur (type B Dorr’s) with an excellent proximal bone stock. The micromotion of implants reduced the bony-anchored stems in two cases.