| 1.ObjectiveTo identify the technical difference between PRU screws insertion and traditional pedicle screws insertion for clinical guidance by comparison in the morphology measurement of PRUs and corresponding pedicles of T1-T10.2.Material and method2.1 common documents30 adult patients were obtained,which was consist of 19 males and 11 females, aging 30-58y,with the averaged age 45.5y,none of which were related with spine disease such as fracture,degeneration,deformity and tumor,then experienced CT scan,with the thickness of 1mm.2.2 method of measurementPhotoShop 9.0 were adopt to measure the CT image with integrated ribs, transverse processes and pedicles.The index measured was below:(1)pedicle rib unit width(PRU-W),pedicle width(PW)(2)pedicle rib unit screw insertion length(PRUL),pedicle screw insertion length(PL)(3)the angle included by central pedicle rib unit axis and sagittal plane(PRU-A), the angle included by central pedicle axis and sagittal plane(PA)(4)safe extent of screw insertion angle via PRU(the maximum and minimum inward angle)2.3 Statistical solutionSPSS 13.0 was used for statistical analysis.Matched pairs t-test,was performed for the data analysis with P＜0.05 considered statistically significant.Data were expressed as(?)±s.3.Result3.1 PRU-W and P-W measurement resultIn TI-10 segment's measurement of PRU-W and P-W,the minimum was in T5 (appeared separately as 13.4±1.5 mm,5.2±0.8 mm)with the maximum in T1 (appeared separately as 17.9±1.5 mm,8.6±0.9mm).The PRU-W diminished from T1 to T5 then increased from T5 to T10.In T1-10 segment PRU-W had statistically significant difference from P-W(t＞3.768,P＜0.01).Meanwhile,the PRU-W between males and females had statistically significant difference(P＜0.01).3.2 PRU-L and P-L measurement resultThe minimal PRU-L and P-L was in T1(appeared separately as 42.6±3.1 mm, 34.3±3.3 mm)with the maximum in T10(appeared separately as 59.4±2.5 mm, 44.6±3.1 mm),which increased from T1 to T10.In T1-10 segment PRU-L had statistically significant difference from P-L(t＞3.369,P＜0.01).Meanwhile,PRU-L of each segment between males and females had statistically significant difference (P＜0.01).3.3 PRUA and PA measurement resultPRUA in T1 was the maximum(appeared separately as 41.4±4.4°,31.1±3.2°) and in T10 was the minimum(appeared separately as 17.5±2.9°;3.8±1.8°),which decreased from T1 to T10.In each segment of T1-T10,PRU-A had statistically significant difference from P-A(t＞2.756,P＜0.01).There was no statistically significant difference in PRU-A between beween male and female.Moreover,the maximum and minimum inward angle of screw insertion were measured.The extent of screw insertion was 20-30°4.Conclusion4.1 Thoracical pedicle rib unit width and screw insertion length were greater than the pedicle width and screw insertion length,so the thicker and longer screws could be inserted via PRU,so as to increase the possibility of safe screw insertion.4.2 It's necessary of a greater inward angle required for screw insertion via PRU, yet the safe extent of PRU screw insertion angle was present.4.3 Notwithstanding the advantage existed in the technique of PRU screw insertion,it's necessary of individualization screw insertion via PRU on the basis of preoperative CT image on account of the significant difference of both PRU-W and PRU-L in gender and the great difference in segments and individuals. |
