Manufacture CASP And Radiographic And Anatomical Measurement Parameters In Thoracolumbar

Objective: To manufacture CASP (Centrum-vertebra-fracture-repairingabsorbable supporting plugger) used for reconctruction the height and the propfunction of traumatic thoracolumbar fracture vertebraes combined posteriorshort-segment transpedicular fixation system, preventing or reducing nail break,barbreak,loss rate of vertebral height and the loss of corrective angle. Throughanatomical measurement to investigate the feasibility and parameters inreconstruction of traumatic thoracolumbar fracture vertebraes transpedicular and itslateral wall. Through radiographic measurement to investigate the parameters inreconstruction of traumatic thoracolumbar fracture vertebraes transpedicular and itslateral wall, providing the length, height and width support for manufacture CASP.Methods:1．Anatomical measurement: Twenty embalmed adult cadavers from T10-L5 wereobtained.All soft tissue were dissected;the spinous process from T11 toL4,laminae,acets and the transverse processes were removed.Anatomic measurementfor medial-lateral width,cranial-caudal height,inner medial-lateral width and innercranial-caudal height of pedicles from T11 to L4,observe and measure the distancebetween the pedicles and nerve roots. Distraction of anterior branch of spinal nerveT12 to L3 and psoas, measurement the width from distracter to medial cortical ofL1-L4 pedicles. Dissected the part costal head of T11 and T12, measurement thewidth from dissected to medial cortical of T11 and T12 pedicles.2．Radiographic measurement: 100 cases of healthy adult volunteers werescanned with 0．6mm slice collimation by means of 64-slice spiral CT laminagraphyfrom T11 to L4, and 2D and 3D images reconstructions were achieved after volumn data was transferred to WEBVIEWER 5．1 GEPACS/wv workstation. Radiographicmeasurement for the height and width and sagittal diameter of vertebral bodies,measurement for medial-lateral width,cranial-caudal height,inner medial-lateral widthof pedicles from T11 to L4．measurement for the length and width of the implants inthe experiment simulation of reconstruction thoracolumbar vertebraes.3．Manufacture CASP: based on the parameters of radiographic and anatomicalmeasurement, simulation manufacture and manufacture CASP used for reconctructionthe height and the prop function of thoracolumbar burst fracture vertebraes.Result:1．The height of T11 pedicle are 15．4±1．3mm,The width of T11 pedicle are10．0±1．5mm,The height of T11 pedicle posterior opening are 12．5±1．5mm,Thewidth of T11 pedicle posterior opening are 5．8±0．6mm; The height of T12 pedicleare 15．9±1．6mm,The width of T12 pedicle are 9．8±1．2mm,The height of T12pedicle posterior opening are 12．0±1．1mm,The width of T12 pedicle posterioropening are 6．0±0．6mm；The height of L1 pedicle are 14．6±1．4mm,The width ofL1 pedicle are 9．3±1．5mm,The height of L1 pedicle posterior opening are 10．8±1．4mm,The width of L1 pedicle posterior opening are 5．6±0．8mm; The height of L2pedicle are 14．1±1．4mm,The width of L2 pedicle are 10．1±1．6mm,The height ofL2 pedicle posterior opening are 11．0 + 1．6mm,The width of L2 pedicle posterioropening are6．2±0．6mm; The height of L3 pedicle are 13．7±1．6mm,The width of L3pedicle are 11．3±1．6mm,The height of L3 pedicle posterior opening are 10．1±1．4mm,The width of L3 pedicle posterior opening ar7．6±1．4mm；The height of L4pedicle are 13．0±1．7mm,The width of L4 pedicle are 12．8 + 2．0mm,The height ofL4 pedicle posterior opening are 9．2±1．4mm,The width of L4 pedicle posterioropening are 8．4±1．2mm. The height of the T11-L4 pedicles vary from 13．7±1．6mm to 15．9±1．6mm,it is high enough for the implants. The width of the T11-L4pedicles are small, but the lateral of T11 and T12 pedicles are costal heads and nonerve roots passing by, when the costal head and the lateral wall were dissected thereare wide enough (≥20mm) for the implants, the lateral of L1-L4 pedicles are psoasand nerve roots ,but it is easy to pull them aside and remove the lateral wall of the pedicles ,there are also wide enough for the implants too.2．To T11 vertebral bodies: the transverse diameter are 32．4±2．8mm,the sagittaldiameter are 25．6±2．5mm,the anterior height are 20．3±2．1mm,the middle heightare 19．1±2．3mm,the posterior height are 21．9±2．2mm；To T12 vertebral bodies:the transverse diameter are 33．6±2．2mm,the sagittal diameter are 25．3±1．7mm,the anterior height are 20．9±2．0mm,the middle height are 19．6±2．2mm,theposterior height are 22．8±2．1mm; To L1 vertebral bodies: the transverse diameterare 36．1±3．2mm,the sagittal diameter are 26．9±2．9mm,the anterior height are22．2±2．4mm,the middle height are 20．1±2．3mm,the posterior height are 24．1±2．1mm; To L2 vertebral bodies: the transverse diameter are 37．2±3．3mm,thesagittal diameter are 27．7±2．5mm,the anterior height are 23．9±2．2mm,the middleheight are 21．4±2．3mm,the posterior height are 24．6±1．7mm; To L3 vertebralbodies: the transverse diameter are 39．6±3．3mm,the sagittal diameter are 28．7±2．0mm,the anterior height are 24．4±1．6mm,the middle height are 21．2±2．3mm,the posterior height are 23．9±2．4mm; To L4 vertebral bodies: the transversediameter are 42．1±4．1mm,the sagittal diameter are 29．0±2．2mm,the anteriorheight are 24．4±1．9mm,the middle height are 21．6±2．2mm,the posterior heightare 23．3±2．9mm。From T11 to L4 the vertebral bodies height are become higherand higher, to T11-L2 vertebral bodies the posterior height are higher than anteriorheight,but to L3,L4 vertebral bodies the posterior height are lower than anteriorheight, to the same vertebral bodies the middle height are lowest. From T11 to L4vertebral bodies the middle height are vary from 19．1±2．3mm to 21．6±2．2mm, thetransverse diameter and sagittal diameter are become more big too; the sagittaldiameter are vary from 25．6±2．5mm to 29．0±2．2mm, the transverse diameter arevary from 32．4±2．8 to 42．1±4．1mm. So, it can be seen from T11 to L4, thetransverse diameter are become biggest, the sagittal diameter are become morebigger than the height of vertebral bodies.3．Based on the date from the study of simulated implantation from 2D imagesreconstructions, To T1 1 vertebral bodies: the width of the implants are 8．5±1．2mm, the length of the implants are 23．3±1．7mm,N the angle of implantation are 5．9±1．2°for the left pedicle and 6．2±1．3°for the right pedicle; To T12 vertebralbodies: the width of the implants are 8．7±1．1mm,the length of the implants are24．2±1．5mm,the angle of implantation are 5．8±1．3°for the left pedicle and 6．9±1．9°for right; To L1 vertebral bodies: the width of the implants are 8．9±1．5mm,the length of the implants are 23．8±1．7mm,the angle of implantation are12．6±1．9°for the left pedicle and 12．7±2．0°for right; To L2 vertebralbodies:the width of the implants are 9．0±1．2mm,the length of the implants are24．4±1．2mm,the angle of implantation are 13．7±1．8°for the left pedicle and13．9±2．0°for right; To L3 vertebral bodies: the width of the implants are 9．5±1．3mm,the length of the implants are 25．5±1．5mm,the angle of implantation are16．4±1．7°for the left pedicle and 16．4±1．8°for right; To L4 vertebralbodies: the width of the implants are 10．8±1．3mm,the length of the implants are25．8±1．9mm,the angle of implantation are 16．3±1．8°for the left pedicle and18．7 + 1．7°for the right. From T11 to L4 the angle of implantation are becomemore bigger, the width of the implants are become more wider too.4．Based on the parameters of radiographic and anatomical measurement,wehave worked out a series of plan for manufacture CASP (width×height×length,mm):①7×9×20mm,②7×9×23mm,③7×9×25mm,④7×9×27mm,⑤8×10×20mm,⑥8×10×22mm,⑦8×10×25mm,⑧8×10×27mm,⑨9×11×20mm,⑩9×11×22mm, (11) 9×11×24mm, (12) 9×11×25mm, (13) 9×11×27mm, (14) 10×12×25mm, (15) 10×12×27mm.Conclusion:1 .Transpedicular and its lateral wall can reconstruct the height of T11-L4vertebraes,and it is the most safe approach for T11-L4 vertebral reconstruction.2．Based on anatomical measurement transpedicular and its lateral wall toreconstruction T11-L4 vertebraes, the parameters of the implants: width≤20mm, height: 11．0mm-17．0mm.3．Based on CT measurement of simulated implantation from 2D images reconstructions, thewidth of the implantation are 7．3-12．0mm, the length of the implantation are 20．0-28．0mm, theangle of implantation vary from 5．9±1．2°to 18．7＋1．7°,and the higth of the implantation are11．0-17．0mm.4．Based on the parameters of radiographic and anatomical measurement,we have manufactedone of the CASP, and have applied patent for invention and applied patent for new style of China.