The term spinal dysraphism defines an incomplete fusion or a bone defect that affects the neural structures of the spinal cord due to a neural tube malformation. A 6-month-old, male, mixed-breed dog, was evaluated for paraparesis, pelvic limb proprioceptive ataxia, faecal and urinary incontinence. A neurological examination indicated an L4-S3 spinal cord segment lesion. A thoracolumbar and lumbosacral spine magnetic resonance imaging was performed and a closed spinal dysraphism, with the presence of a lipomyelomeningocele, was detected. The magnetic resonance imaging showed an entire narrowing passage and a fibrous mass stemming from a wedge-shaped gap in the caudal region of the dorsal lamina of the L4 vertebra, leaving the spinal canal towards the skin surface in the region where the skin stigma was observed. A dorsal laminectomy was performed, the spinal cord was exposed, and the entire fibrous mass was excised. Three months postoperatively, the patient had a complete resolution of the urinary and faecal incontinence showing only a residual mild paraparesis, which remained six months after surgery. The surgical procedure resulted in the satisfactory recovery of the neurological signs.

This study aims to evaluate the effect of autologous adipose-derived mesenchymal stem cells (AAD-MSC), with and without synthetic absorbable hydroxyapatite (HAP-91), on the bone regeneration in rabbits. Thirty-four female white New Zealand rabbits were submitted to a 10 mm distal diaphyseal radius ostectomy, divided into 3 experimental groups according to the treatment established. The bone gap was filled with 0.15 ml of a 0.9% saline solution containing two million AAD-MSC (G1), or AAD-MSC associated with HAP-91 (G2). The control group (CG) received only 0.15 ml of the 0.9% saline solution. Radiographs were made post-operatively, and after 15, 30, 45 and 90 days. Fifty percent of the samples were submitted to a histological examination at 45 days and the remaining ones at 90 days post-operatively. Radiographically, the periosteal reaction, bone callus volume and bone bridge quality were superior in G2 (P < 0.05). Histologically, the bone repair was faster and more efficient in G1 at 45 days (P < 0.05). In conclusion, AAD-MSC improved the regeneration on the experimentally induced bone defects in rabbits; however, the use of hydroxyapatite requires caution given the granulomatous reaction produced in the species.