A Novel Total Cervical Prosthesis for Single-Level Cervical Subtotal Corpectomy Radiologic and Histomorphometric Analysis in a Caprine Model

Study Design: A novel total cervical prosthesis (TCP) for single-level cervical subtotal corpectomy was assessed in a caprine animal model. Objectives: To investigate the radiologic and histomorphometric characteristics of a novel TCP for single-level cervical subtotal corpectomy. Summary of Background: Cervical disk replacement has emerged as a promising alternative to arthrodesis in the management of cervical disk herniation. However, they are designed for anterior cervical discectomy, and not suitable for cervical subtotal corpectomy. To solve this problem, our group has developed a novel TCP for single-level cervical subtotal corpectomy. Materials and Methods: There were 12 adult Shannxi goats (2 y old) used in this study. The goats were divided into 2 groups based on postoperative survival periods of 3 (n= 6) and 6 (n= 6) months after surgery. Using an anterior surgical approach, a standard anterior C3 vertebra subtotal corpectomy and decompression of the spinal canal were performed, followed by implantation of the TCP device. Then all the goats were killed and underwent radiographic and histologic observations. Results: The TCP implant procedures were successfully completed in all 12 goats without incidence of vascular or infectious complications. The range of motion of C2-C3 and C3-C4 segments were preserved in both of the groups. Three-dimensional images of specimens interface indicated confluent interdigitization of trabeculae at the prosthetic endplate-bone interface, without evidence of significant radiolucent lines or gaps. Histomorphometric analysis showed that there were a large number of fibrous tissue and a small amount of cartilage cells between the prostheses and bone in the 3 months' group. In the 6 months' group, part of fibrous tissue has changed into the cartilage tissue. Conclusions: Our data show that this prosthesis can maintain the stability of the cervical spine and retain the activity of the cervical spine in vivo. The findings in this study provide a foundation for ongoing clinical investigations using the TCP.