Relationship of actual laminoplasty opening size and increment of the cross-sectional area based on single-door cervical laminoplasy

Abstract

Background:Amounts of clinic research have been performed to investigate the increment of cross-sectional area in single-door cervical laminoplasty (SDCL). However, no one has taken the effects of surgery drill into consideration.Methods:A mathematical model was built to investigate the relation of actual laminoplasty opening size (LOS), the transverse canal diameter (TCD), and the increment of cross-sectional area in SDCL). The model was based on geometric analysis on deformation of spinal canal; the relation was derived and characterized as: , where a is the TCD, b the actual LOS, c the size of mini-plate, and d is diameter of the surgery drill bit. In the equation, the related variables would be measured to estimate the increment of cross-sectional area before the surgery. In the current research, 25 patients authorized to use their CT scans of C3∼C7 as the subject samples.Results:The effects of surgery SDCL were very significant; for each patient, the cross-sectional area was enlarged dramatically after the surgery (P < .01). On the contrary, the difference between the cross-sectional area obtained by the equation and that measured by software was statistically negligible (P > .05), which confirmed the reliability of the modeling equation.Conclusions:Before the SDCL, increment of the cross-sectional area can be estimated by the above-mentioned modeling equation with a high-level reliability. This method ensures the optimum selection of mini-plate before operation for each patient.

Comparison of Spinal Canal Expansion Following Cervical Laminoplasty Based on the Preoperative Lamina Angle : A Simulation Study

“…When performing both techniques, the laminoplasty opening size (OS) has the greatest impact on the amount of spinal canal area (SCA) after surgery. Several studies have reported that there is a relationship between OS and SCA 6,20) . However, a comparison of the increase in the SCA following ODL and DDL according to the preoperative lamina angle (LA) has rarely been performed.…”

Ten‐Year Surgical Outcomes and Prognostic Factors for French‐Door Laminoplasty in the Treatment of Multilevel Cervical Spondylotic Myelopathy

“…Studies asserted that the incidence of axial symptoms after laminoplasty was up to 45%-80% and the overall incidence of C5 palsy was about 4.6% [30]. Current studies believed that factors such as the destruction of the posterior cervical structures, the instability of the facet joint, and the atrophy of the posterior cervical muscles caused by prolonged intraoperative traction were correlated with the axial symptoms [31] and that C5 palsy is correlated to traction after the spinal cord drifted backward, segmental ischemia, and ischemia-reperfusion injury of the spinal cord [30][31][32]. In our study, long operative time was one of the risk factors correlated with the axial symptoms.…”

Volumetric analysis of bilateral spinal canal decompression via hemilaminectomy versus laminoplasty in cervical spondylotic myelopathy

“…Conversely, in our historic cohort, the lifted lamina was sutured to the paravertebral musculature to ensure its position, rendering it susceptible to postoperative shift and reclosure. Studies have shown that spinal canal enlargement after LP is dependent upon LP opening size (LOS) and that this can be greatly improved upon using the appropriate miniplates for lamina fixation [ 21 ]. The lack of use of tailored miniplates might have contributed to the inferior volume gain observed in the LP cohort.…”