Three-dimensional CT measurement of anatomical parameters related to posterior cervical endoscopic surgery

English Keywords:Cervical vertebrae  Endoscopic surgery  Anatomy  Three-dimensional CT

English Abstract:

  【Abstract】 Objectives: To measure three-dimensional CT of the bony structure at posterior cervical spine and provide reference data for posterior endoscopic surgery. Methods: 214 patients who underwent cervical three-dimensional CT examination in our hospital in June 2025 were enrolled, including 113 males(mean age: 52.1±8.9 years, BMI 21.2±5.8kg/m2) and 101 females(age 49.7±9.0 years, BMI 22.4±4.7kg/m2). There were no significant differences in age or BMI between male and female patients(P>0.05). Cervical CT three-dimensional reconstruction and measurements were performed in the imaging system. The posterior structures of C3 to C6 were divided into three parts as the spinous process, lamina and lateral mass. Measurements included spinous process length, tilt direction, tilt angle, height, and width; lamina length, thickness, and height; lateral mass width, height, and thickness. Differences among segments were compared using one-way ANOVA. Results: No significant differences were observed in any measured parameters between sexes or between left and right sides(P>0.05). The proportion of left-tilted spinous processes ranged from 19% to 33%, non-tilted from 24% to 57%, and right-tilted from 14% to 43%; no significant difference was found between the proportions of left- and right-tilted processes(P>0.05). Spinous process length differed significantly among segments(P<0.05), with C7 being the longest(32.5±3.0mm) while C3 and C4 the shortest(11.4±2.5mm and 11.6±1.9mm, respectively). No significant difference in tilt angle was observed between C7(26.4°±8.1°) and C6(27.2°±5.7°)(P>0.05), and both were larger than other segments(P<0.05). Spinous process height also differed significantly among segments(P<0.05); C7 height(10.5±3.1mm) was greater than other segments(P<0.05), while C3(7.8±1.9mm) and C4(8.0±2.3mm) were significantly smaller than others(P<0.05). Lamina length differed significantly among segments(P<0.05), with C7 being the longest(13.4±2.8mm) and C3 the shortest(9.7±1.6mm). Lamina thickness also showed significant differences(P<0.05), with C4 the thinnest(2.2±0.6mm) and C7 the thickest(3.1±0.8mm). No significant difference in lamina height was found between C4(10.4±2.3mm) and C5(11.1±1.9mm)(P>0.05), and both were smaller than other segments(P<0.05); C7 lamina height(15.8±3.2mm) was greater than other segments(P<0.05). Lateral mass width: C7(10.5±3.2mm) was the largest(P<0.05), with no significant differences among other segments(P>0.05). Lateral mass height: no significant difference between C3(10.3±1.9mm) and C4(10.5±1.7mm)(P>0.05), both smaller than others(P<0.05); C7(12.2±1.3mm) was larger than others(P<0.05). Lateral mass thickness: C3(9.7±2.1mm) was smaller than other segments(P<0.05); no significant difference between C6(12.2±1.1mm) and C7(12.5±0.9mm)(P>0.05), and both were larger than other segments(P<0.05). Conclusions: Spinous processes may exhibit tilt in each cervical segment, and lamina thickness varies across segments. Lamina length increases from cephalad to caudad, therefore, more caudal lamina resection is required during decompression surgery. There is no significant difference in lateral mass width among segments.