Purpose of the Study: The outcome after revision knee arthroplasty with structural distal femoral allograft augmentation for major bone loss has been rarely reported in the literature. The aim of this study was to assess the outcome for patients managed with such a procedure in our hospital.

Materials and Methods: Since 2001, ten revision knee arthroplasties requiring structural distal femoral allograft for major bone loss were performed in nine patients who underwent surgery at mean age of 68.1±9.8 years and prospectively followed. All patients were operated by the same surgical team. The first assessment was completed for the patients during August 2005 for radiographic and clinical evaluation. The mean follow up time was 22.2±15.1 months.

Results: On radiographic analysis none of the allografts had resorbtion. Implant position

Was preserved in all patients. Two patients had postoperative complications: one had superficial wound infection without need of surgical revision, another patient needed angioplasty because of pseudoaneurisma of popliteal artery and temporary using of knee brace for mild medial instability. Clinical evaluation revealed that mean “Hospital for Special Surgery Score” had improved from 39.8 to 84.1 points and mean range of motions improved from 75.0±42.0 to 103.5±12.5 (p=0.05, paired t-test). Before the surgery all patients used a walker or a crutch, while only one of them used a cane and the remaining patients walked without any support after the operation.

Conclusions: Our preliminary results demonstrate that structural femoral allografts used in revision knee replacement improve clinical and functional outcomes. Further follow-up is planned.

In recent years advances in operative techniques have allowed surgeons to perform total hip arthroplasty (THA) through incisions much smaller than those used previously. Potential advantages of these techniques include the reduction of blood loss and pain in the immediate postoperative period and preserving muscle function.

Potential disadvantages might include increased wound infection rate due to skin ischemia, intraoperative neurovascular injuries, and component malposition. This in turn may lead to long term complications, such as instability, osteolysis, and loosening.

The purpose of this study is to present our results with total hip arthroplasty performed through a minimal invasive technique which is a modification of the standard posterolateral approach.

Methods: In this retrospective study 91 consecutive patients underwent primary total hip arthroplasties were reviewed. The surgeries were performed at our institution from January 2001 to December 2003.

Surgical indications included primary osteoarthritis, subcapital fractures, malignancy, hip displasia, Otopelvis, rheumatoid arthritis and AVN. Exclusion criteria included revision hip arthroplasty, and cemented operations.

A modification of the standard posterlateral approach was used. Standard hip arthroplasty instruments along with curved acetabular reamers and impactor were used. Incision extent was determined by the size of the acetabular component. A fully Hidroxyapetite coated stem, and porous coated acetabullar component were used. Immediate full weight bearing postoperative regimen was allowed in all cases.

Results: In 17 patients (group A) the indication for surgery was a recent subcapital fracture. 74 patients (group B) had no trauma. The average age was 64.2 in group A and 65.1 in group B. No case of deep infection was documented in either group. 5 patients in group B had a single event of a posterior dislocation that was treated successfully with closed reduction. No dislocation occurred in group A. 35% (4) of group A and 41% (22) of group B did not require postoperative blood transfusions. 47% (6) and 36% (14) respectively needed transfusion of 3 blood units or more. Average hospitalization time was 6 days. None of the patients in both groups needed re-operation.

Conclusions: Minimally invasive total hip arthroplasty is associated with a short hospitalization period and relatively low rate of blood transfusion. No major wound healing problems were documented in our series. It appears that the relatively high dislocation rate might be explained partly due to the common use of ceramic inserts. Further modification of the technique for proper acetabular component orientation is needed. However, more prospective with longer follow-up research must be conducted before definitive recommendations can be made.

Osteochondral lesions are frequent as a result of sport and daily activities.

The healing processes of these defects are prolonged and complicated and often leading to irreversible ostheo-arthritic changes. In this study, biotechanical and bioChemical approaches are being combined in an attempt to identify potential uses of biofabricated marine carbonate materials in biomedical applications, particularly as for remodeling cartilage and bone tissue. Biofabricated material was grafted into osteochondral induced defects in animals’ models during knee arthrotomy. Using histological sections, SEM, EDS studies it was revealed that the biofabricated, porous material is highly biocompatible. The graft was incorporated into the osteochondral defect area and followed by surface remodeling. After 4 months the interface and subchondral areas were been replaced by new cartilage and bone.

We believe that it is the first time that such biofabricated materials have been used for biomedical purposes. In face of the obvious environmental disadvantages of harvesting from limited natural resources, we propose the use of bio-engineered coralline and other materials such as those cultured by our group under field and laboratory conditions as a possible biomatrix for hard tissue remodeling.