A Biomechanical Comparison among Three Surgical Methods in Bilateral Subaxial Cervical Facet Dislocation.

Byun, Jae Sung; Kim, Sung Min; Choi, Sun Kil; Lim, T Jesse; Kim, Daniel H

Original Article

Journal of Korean Neurosurgical Society 2005;37(2): 89-95.

Jae Sung Byun, Sung Min Kim, Sun Kil Choi, T Jesse Lim, Daniel H Kim

¹Department of Neurosurgery, Hallym University Medical Center, Seoul, Korea. spinekim@hallym.or.kr
²Department of Neurosurgery, Stanford University Medical Center, Stanford, California, USA.

ABSTRACT

OBJECTIVE
The biomechanical stabilities between the anterior plate fixation after anterior discectomy and fusion (ACDFP) and the posterior transpedicular fixation after ACDF(ACDFTP) have not been compared using human cadaver in bilateral cervical facet dislocation. The purpose of this study is to compare the stability of ACDFP, a posterior wiring procedure after ACDFP(ACDFPW), and ACDFTP for treatment of bilateral cervical facet dislocation. METHODS: Ten human spines(C3-T1) were tested in the following sequence: the intact state, after ACDFP(Group 1), ACDFPW(Group 2), and ACDFTP(Group 3). Intervertebral motions were measured by a video-based motion capture system. The range of motion(ROM) and neutral zone(NZ) were compared for each loading mode to a maximum of 2.0Nm. RESULTS: ROMs for Group 1 were below that of the intact spine in all loading modes, with statistical significance in flexion and extension, but NZs were decreased in flexion and extension and slightly increased in bending and axial rotation without significances. Group 2 produced additional stability in axial rotation of ROM and in flexion of NZ than Group 1 with significance. Group 3 provided better stability than Group 1 in bending and axial rotation, and better stability than Group 2 in bending of both ROM and NZ. There was no significant difference in extension modes for the three Groups. CONCLUSION: ACDFTP(Group 3) demonstrates the most effective stabilization followed by ACDFPW(Group 2), and ACDFP(Group 1). ACDFP provides sufficient strength in most loading modes, ACDFP can provide an effective stabilization for bilateral cervical facet dislocation with a brace.

Key Words: ACDF; Additional posterior wiring; Anterior cervical plate fixation; Bilateral cervical facet dislocation; Biomechanical testing; Posterior transpedicular fixation