Total fraction of mononuclear intra-articular cells in dogs undergoing cruciate ligament reconstruction

This study was performed to evaluate the action of the fraction of total mononuclear cells from the bone marrow (FCMO) applied intra-articularly after the surgical repair of an experimentally ruptured cruciate ligament. Twenty dogs which suffered one-sided cruciate desmotomy of the cranial and caudal cruciate ligament 21 days before the correction were used. Ten animals received the FCMO at the time of correction. The assessments were done through X-ray and clinical examinations, and biopsies at 50 and 90 days postoperatively. It was concluded that there was no clinical difference between the two groups until 90 days of evaluation. The group that received FCMO grew intra-articular bone shown on the X-ray study. All twenty animals, however, presented cells marked with CD34 antibodies on their biopsy samples, indicating the presence of stem cells in both groups. It is concluded that for the experimental model, it is not recommended to use the mononuclear cell fraction, and in experimental studies with the use of stem cells in the joints models whose focus of injury keep direct contact with the bone marrow should be avoided.