Murine models of posterolateral spinal fusion: A systematic review.

BACKGROUND: Rodent models are commonly used experimentally to assess treatment effectiveness in spinal fusion. Certain factors are associated with better fusion rates. The objectives of the present study were to report the protocols most frequently used, to evaluate factors known to positively influence fusion rate, and to identify new factors. METHOD: A systematic literature search of PubMed and Web of Science found 139 experimental studies of posterolateral lumbar spinal fusion in rodent models. Data for level and location of fusion, animal strain, sex, weight and age, graft, decortication, fusion assessment and fusion and mortality rates were collected and analyzed. RESULTS: The standard murine model for spinal fusion was male Sprague Dawley rats of 295g weight and 13 weeks' age, using decortication, with L4-L5 as fusion level. The last two criteria were associated with significantly better fusion rates. On manual palpation, the overall mean fusion rate in rats was 58% and the autograft mean fusion rate was 61%. Most studies evaluated fusion as a binary on manual palpation, and only a few used CT and histology. Average mortality was 3.03% in rats and 1.56% in mice. CONCLUSIONS: These results suggest using a rat model, younger than 10 weeks and weighing more than 300 grams on the day of surgery, to optimize fusion rates, with decortication before grafting and fusing the L4-L5 level.

Anterior approach to remove a pre-medullary meningioma in the cervical spine: Technical case report.

BACKGROUND: Regarding their relation to the spinal cord (SC), resection of pre-medullary meningiomas may be technically challenging. Anterior approach via corpectomy represents a nice option reducing the need for mobilization of the SC. CASE DESCRIPTION: We describe the case of a patient presenting with a cervical meningioma, located anterior to the SC and operated on through an anterior approach. Surgery consisted of a 2-levels discectomy and C7 corpectomy, midline opening of the dura and then microsurgical resection of the tumor. After coagulation of the implantation base, the dura was then closed in a watertight fashion. Finally, the anterior column was reconstructed using a titanium mesh-cage and anterior plating. CONCLUSION: In the case of cervical meningioma located anterior to the SC, anterior approach may be considered as an alternative option to remove the tumor.