Mesenchymal stem cells from minced umbilical cord fragments may represent a valuable cell population for cartilage and bone tissue engineering A promising approach for cartilage and bone repair is the use of umbilical cord mesenchymal stem cell (UC-MSC)-based tissue engineering. Through a simple and efficient protocol based on mincing the umbilical cord, a consistent number of multipotent UC-MSCs can be obtained. The aim of this in-vitro study is to investigate the pluripotency of UC-MSCs and, in particular, the chondrogenic and osteogenic potential of UC-MSCs grown in tridimensional scaffold, in order to identify a potential clinical relevance for patients who might benefit from MSCs-therapy.Summary Statement
Introduction
Hypoxia enhances chondrocyte phenotype of cells migrating from cartilage fragments, thus supporting the use of chondral fragment as a potential cell source for one-stage cartilage repair Minced cartilage fragments are a viable cell source for one stage cartilage repair, as shown in both in preclinical and clinical studies. However, the joint microenvironment, in which the repair process takes place, is hypoxic and no evidences are present in literature regarding the behaviour of cartilage fragments in a hypoxic environment. Aim of the study is to verify if hypoxia could influence chondrocyte outgrowth from cartilage fragments into a Hyaluronic-Acid/fibrin scaffold and evaluate its effects on migrating chondrocyte behaviour, compared to normoxic condition. This could be significant in the perspective of a wide clinical application of human chondral fragments for single stage repair.Summary Statement
Introduction
Preoperative bone-marrow-derived cell mobilization by G-CSF is a safe orthopaedic procedure and allows circulation in the blood of high numbers of CD34+ve cells, promoting osseointegration of a bone substitute. Granulocyte-colony-stimulating-factor(G-CSF) has been used to improve repair processes in different clinical settings for its role in bone-marrow stem cell(CD34+ and CD34-) mobilization. Recent literature suggests that G-CSF may also play a role in skeletal-tissue repair processes. Aim of the study was to verify the feasibility and safety of preoperative bone-marrow cell (BMC) mobilization by G-CSF in orthopaedic patients and to evaluate G-CSF efficacy in accelerating bone regeneration following opening-wedge high tibial valgus osteotomy(HTVO) for genu varum.Summary Statement
Introduction
The ABG total hip prosthesis had been studied to prevent any kind of stress shielding and to allow the localization of the loads in the metaphiseal region of the femur. The aim of this study was to analize the effective behaviour of the loads in long-term implants and the possible correlations of those findings with the clinical situation of the patients. We considered 87 total hip arthroplasty implants executed from 1989 to 1995 and performed by using Anatomique Benoist Girard I uncemented prosthesis. The radiographical findings have been classified observing Engh’s stability criteria according to Gruen’s subdivision of the periprosthetic femoral zones. The radiographical analysis shows a higher presence of can cellous densification in Gruen’s zones 3 and 5 than the one found in zones 2 and 6. Furthermore the presence of a cortical reaction is more relevant in the distal zones.>
Radiolucent lines are present in 16% of the cases in zone 4; their percentage in zones 3 and 5 decreases to 7.14% and 10.71%. Our study shows the certain presence of the stress shielding mechanism in long-term analysis and documents that the main region of late anchorage is the distal, not hydroxyapatite-coated, one.>
The comparison with other similar studies shows the decrease of the presence of radiolucent lines in proximal femoral zones with the rise of the follow-up: it can be interpreted as the lesser presence of micro movements of the tip of the prosthesis due to the distalization of the anchorage.
