The Establishment Of Pedicle Lengthening For The Treatment Of Lumbar Spinal Stenosis Of The C Arm Monitoring Method

Lumbar spinal canal stenosis(Lumbar spinal stenosis,LSS)is a common disease in spinal degenerative typical symptoms of claudication.For people over 60 years of age,the incidence rate is up to 47%.For patients with severe stenosis of the spinal canal,the surgery is the main treatment method.Compared with the traditional open decompression surgery,minimally invasive surgery has less trauma,quicker recovery,less complications and other advantages,and has gradually become the focus of scholars.The existing micro invasive treatment is done by means of posterior muscle clearance and by the use of the working channel to arrive at the corresponding position of expansion stealth to complete the operation,which have reached the requirements of minimally invasive incision,but the internal organizational structure may have been subject to great damage,so it is of great significance to explore more ideal minimally invasive scheme.Pedicle lengthening(Pedicle-lengthening Osteotomy,PLO)is a new method for the treatment of lumbar spinal stenosis presented in recent years.It is reported that for the short term effects of the treatment of lumbar spinal stenosis,it has good clinical application prospect.But because of the complexity of the local anatomy of the lumbar spine,in the process of breaking away from the pedicle it may cause serious complications such as nerve and vascular injury,dural rupture,leakage of cerebrospinal fluid,and nerve root injury of cauda equina,venous plexus rupture bleeding.Therefore,how to effectively and safely cut pediculotomy to complete decompression and avoid damaging structures like blood vessels,is a key to reduce the complications of pedicle lengthening.The commonly used pedicle puncture positioning technology is for the vertebral body,instead of the pedicle itself where pedicle lengthening osteotomy is at.Therefore,the puncture technique of pedicle lengthening is very different.There is no known literature reported on the specific steps of pedicle lengthening.In addition,the previous relevant research mainly focus on that decompression is safe and effective in the aspects of anatomy and biomechanics on the hypothesis of pedicle extension being complete.The data source is normal,and the measurements of lumbar spinal stenosis are less.In this study,we use lumbar specimen general observation,image anatomy and digital three-dimensional reconstruction technique to find the best way to determine the optimal osteotomy point in x-ray fluoroscopy,guide pedicle screw and simulate lumbar pedicle extension surgery,observe and measure the anatomical relationship between osteotomy of the lumbar pedicle extension and adjacent nerve structures-providing data support for a safety osteotomy in the process of lumbar pedicle lengthening in order to reduce neurological impairment complications.On this basis,we constructed the osteotomy knife for the lumbar pedicle extension,and completed the C-arm monitoring under the lumbar pedicle truncation.On this basis,we carried out the pedicle extension and expanded the spinal canal.At the same time we have established a set of effective treatment of lumbar spinal stenosis of the technical path,in the C-arm monitoring,through the pedicle extension surgery.The establishment of this method provides a technical support for individualized extension of the pedicle.This research project is divided into three parts to elaborate on the above.I.Lumbar pedicle screw extension-osteotomy site anatomy and image digitalization studyOBJECTIVE: To establish a locus marker for the pedicle screw extension of the pedicle of the lumbar pedicle under the C-arm monitoring.To provide data support for constructing the pedicle osteotomy knife and for a safe implementation of Pedicle extension.Methods: 1.Observing and analyzing the dry specimens of lumbar spine(L3-L5)and x-ray morphology.2.Using Mimics software to reconstruct 100 patients with lumbar spinal stenosis using 3D model.Then,the pedicle extension was simulated and the data were analyzed.Results: 1.Vertebral posterior horn structure in the lower lumbar spine appears,and the posterior wall of the vertebral body and pedicle basal relative constant.The structure is shown on the x-ray lateral slice as the posterior vertebral body.2.Contrast pedicle simulation truncated by pedicle midline plane vertebral canal area,before and after data showed that in the vertebral body attachment back 2 mm,3 mm,4 mm,spinal canal area were significantly expanded,the difference is statistically significant.3.The simulated pedicle extension of the pedicle is almost always in the humanoid ridge at L1-L4,and L5 is located near the intersection of the base of the articular process and the midpoint of the transverse process.4.It has the obvious individual differences in surface morphology of bone cutting.Conclusion:1.The posterior angle of lumbar vertebral bodies,posterior vertebral body line can be used as C arm pedicle extension under monitoring to determine pedicle bone cutting surface mark.2.Using Mimics software to build vertebral pedicle extension and simulation,the data show that the method can effectively expand the area of vertebral canal.3.Using Mimics software to simulate the pedicle axis and the reference after vertebral body bone cutting Angle,because of the cutting point is relatively close to the edge of vertebral nerve root exports,recommend the path to the axis of the needles are inserted into the needle head side direction Angle slightly more safer.4.Individualized vertebral body modeling,simulated osteotomy.Provide morphological data support for performing surgery as well as improving aspects related to needle entry and needle placement,osteotome work and position accuracy.II.Pedicle extension cutting device and preparation of its supporting toolsOBJECTIVE: To develop an osteotomy knife suitable for lumbar pedicle extensionMethods:With reference to the characteristics of the existing pedicle screw puncture tool and the corresponding anatomical parameters,using the engineering software to design an osteotomy knife and its supporting tools for pedicle segmentation.Results: The design of the osteotomy knife and its supporting tools is completed.The samples that meet the requirements are produced.Pedicle extension was successfully performed.Conclusion: This study designed a pedicle extension device and its supporting means,for which a patent right has been granted.III.Establishment and verification of the working method of lumbar pedicle screw extension under the C-arm monitoringOBJECTIVE: To establish a safe and reproducible method for lumbar pedicle screw extension under the C-arm monitoringMethods: With the use of the self-made pedicle osteotomy knives,the pedicle cut off was implemented for L3,L4,L5 three segments of 5 complete Lumbar spine samples.With the use of the self-made screw for extension,spinal canal expansion and extension surgery was implemented.The general specimens and imaging data were measured before and after operation.The main measuring indexes were Transverse Screw Angle(TSA),Sagittal Screw Angle(SSA),pedicle screw path length(PL)(Osteotomy plane Depth,OD),Longest Axis of Osteotomy plane(LOA),Least Axis of Osteotomy plane(LEA),and Osteotomy plane Inclination(OI).And the cortical thickness of the superior wall(CTS),the cortical thickness of the inferior wall(CTI),the cortical thickness of the medial wall,CTM),the cortical thickness of the lateral wall(CTL).Entry point(EP).The differences between the operation method and the osteotomy and the preoperative planning were analyzed.Results: 1.For five specimens of L3,L4,L5 segments,a total of 15 vertebral bodies,the bilateral pedicle extension surgery was implemented.After placing the extendable screw,the pedicle extension distance is 3mm.The area of spinal canal was significantly higher than that before operation(P <0.05).2.A comparison of the preoperative planning and the postoperative imaging data shows that the two fit well.Bone cutting plane four cortical thickness(P > 0.05,no significant difference statistically significant),the longest axis and short axis(P > 0.05,no significant difference statistically significant),bone cutting plane area of contrast(P > 0.05,no significant difference statistically significant).3.The use of AP,lateral,pedicle axial plate and pedicle needle axial plate can achieve a precise placement of the osteotomy knife to complete the cutting.Conclusion: According to the posterior angle of the vertebral body,under the C-arm AP,lateral and pedicle axial and pedicle needle axial monitoring,the self-made osteotomy knife can be used to reliably complete the pedicle truncation and to perform pedicle extension,which is good operability,precision and good repeatability.