CEUS evaluation in the pseudarthrosis before and after treatment with autologous transplantation of bone marrow stem cells: preliminary results

Purpose: To demonstrate the effectiveness of CEUS in evaluating the process of reparative bone regeneration by monitoring angiogenesis around the fracture site in patients with pseudarthrosis who were treated with transplantation of marrowderived mesenchymal stem cells. Methods and Materials: The method was used in 15 patients of the Traumatology Centre in Torino, Italy from February 2009 to May 2011. All patients were treated for delayed multifragmentary fracture evolved in pseudarthrosis. Autologous concentrate of bone marrow stem cells was applied into the area of bone defect. CEUS examination was performed before the gelatinous compound was applied and at one-, four- and twelve-week follow-up time points, in order to evaluate the physiological formation of new blood vessels. At the end of the study an X-ray confirms the presence of callus. Results: Ecographic signs of neo-vascularisation were noted at one week in 13 of 15 patients; a steady increase in vascularity was demonstrated in 13 patients in subsequent tests; repeated measures ANOVA demonstrated statistically significant differences in the extent of vascularisation at subsequent follow-up time points (P < 0.0001). At the end of the study x-ray examination revealed initial attachment of calcified callus in those patients who demonstrated an increase in vascularity at CEUS. The other two patients showed no improvement because of the presence of haematoma. Conclusion: Transplantation of stem cells is a new treatment of pseudoarthrosis; our results demonstrate that CEUS has a good predictive value on the formation of callus in that it affords the monitoring of the reparative tissue vascularity.