Abstract
Background: Pre-clinical randomized controlled animal trials have been conducted to evaluate the effect of mesenchymal stem cell (MSCs) transplantation on intervertebral disc (IVD) degeneration. MSCs can be obtained from different tissues, but systematic studies concerning the effects of muscle-derived MSCs injections on canine naturally degenerated IVD are still lacking. The aim of this study is the assessment of the clinical safety of this technique and its effects on the imaging features of the lumbosacral IVD. Methods: Eight adult healthy Beagle dogs were used in this study. In the preliminary phase, viability of muscle-derived MSCs in presence of contrast medium was assessed. In the clinical assessment phase, MSCs were injected in the lumbosacral IVD by computed-tomography (CT) guidance, after the injection of contrast medium to assess the correct intradiscal needle position. Regular clinical examinations were performed and pre- and post-injections (CT) and magnetic resonance imaging (MRI) features of the IVD were assessed. Results: The percentage of viability of MSCs in the presence of contrast medium ranged from 90 to 98%. 3x106 MSCs were obtained from six dogs and injected in the IVD. No major or minor complications were reported during the procedure and no abnormalities were noticed during the clinical examinations. No statistically significant variations were noticed between the pre- and post-injections imaging features. Conclusion: This technique is clinically safe and it is not associated with any progression of the IVD degeneration, detected by CT and MRI imaging.