Repair of the Canine Vertebral Lamina With a Combination of Autologous Micromorselized Bone and Poly-Lactic Acid Gel After a Total Laminectomy

The complications of a total laminectomy can include epidural scar adhesion, secondary vertebral canal stenosis and lumbar instability. The aim of this study was to assess the ability of a combination of autologous micromorselized bone and polylactic acid (PLA) gel to stimulate bone repair within canine vertebral lamina defects, as well as to prevent peridural adhesion following a laminectomy. Twenty dogs underwent a L1, L3 and L5 laminectomy after a pre-computed tomography examination. The 60 laminectomies were divided into 4 groups, and underwent the following treatments: Group A were treated with a combination of autologous micromorselized bone and PLA gel (n = 16); Group B were treated with micromorselized bone only (n = 16); Group C with PLA gel only (n = 14); and Group D were left untreated as they were the blank controls (n = 14). Vertebral laminae were harvested at 4th and 8th weeks, and examined by computed tomography and histological staining. Significant bone regeneration was observed at 4 and 8 weeks in Groups A and B, although the newly formed bone in the latter group was more irregular in shape. Spinal canal cross-sectional areas in Group B decreased as compared with those in Group A(p < 0.05), and the degree of peridural adhesion in Groups A and C was significantly lower compared with Groups B and D (p < 0.05). These findings indicate that a combination of micromorselized bone and PLA gel may provide a better strategy for the treatment of spinal stenosis.