Liu Jiantao, Zhang Feng, Gao Zhengchao, Li Yuhuan, Niu Binbin, He Xijing
Department of Orthopedics, Second Affiliated Hospital of Xi'an Jiaotong University, No. 157, The West Fifth Road, Xincheng District, Xi'an, Shaanxi, People's Republic of China.
Department of Orthopedics, The Fourth Hospital of Xi'an, Xi'an, Shaanxi, People's Republic of China.
Arch Orthop Trauma Surg. 2017 Nov;137(11):1467-1476. doi: 10.1007/s00402-017-2753-4. Epub 2017 Sep 9.
In this study, we aimed to design a movable artificial lumbar complex (MALC) prosthesis for non-fusion reconstruction after lumbar subtotal corpectomy and to establish an in vitro anterolateral lumbar corpectomy non-fusion model for evaluating the biomechanical stability, preservation of segment movements and influence on adjacent inter-vertebral movements of this prosthesis.
Imaging was performed on a total of 26 fresh goat lumbar spine specimens to determine which of the specimens did not meet the requirements (free of deformity and fractures); the residual specimens were randomly divided into an intact group, a fusion group and a non-fusion group. Bone mineral density (BMD) was tested and compared among the three groups. Biomechanical testing was conducted to obtain the range of motion (ROM) in flexion-extension, lateral bending at L2-3, L3-4 and L4-5 and axial rotation at L2-5 in the three groups.
Two specimens were excluded due to vertebral fractures. BMD showed no statistical significance among three groups (P > 0.05). The stability of the prosthesis did not differ significantly during flexion, extension, and lateral bending at L2-3, L3-4, and L4-5 and axial torsion at L2-5 between the intact group and the non-fusion group (P > 0.05). Segment movements of the specimens in the non-fusion group revealed significantly decreased L2-3 ROM and significantly increased L3-4 and L4-5 ROM in flexion and lateral bending compared with the fusion group (P < 0.05).
Reconstruction with a MALC prosthesis after lumbar subtotal corpectomy not only produced instant stability but also effectively preserved segment movements, without any abnormal gain of mobility in adjacent inter-vertebral spaces. However, additional studies, including in vivo animal experiments as well as biocompatibility and biomechanical tests of human body specimens are needed.
