The Basic Research Of The Minimally Invasive Paraspinal Intermuscular Approach Surgery Of Lumbar Spine In Ultrasound Assisted Navigation

Objective:More and more researches have found that in lumbar spine surgery,the traditional posterior approach spinal surgery is easy to cause the injury of the muscle,ligament and nerve and lead to postoperative spinal instability that occurs in patients with intractable low back pain and other symptoms,which may seriously affect the quality of life.In order to preserve the integrity of the structure and function of the spine better,with the alleviation of the pain,this research focused on the paraspinal intermuscular approach surgery of lumbar spine.Paraspinal intermuscular approach takes advantage of gaps between adjacent two muscles natural plane for surgery need not to strip muscles,which could avoid muscle injury during the operation,and reduce bleeding and protect the nerves.The key of the surgery is the orientation of paraspinal intermusculare.If the orientation is not accurate,the intermuscular approach may turn into intramuscular approach,followed by the injury of muscle and the nutrient vessels and innervation.Due to the real-time steering characteristic of ultrasound,using ultrasound instrument,this research intends to find lumbar paraspinal muscle space and comprehend the feasibility and accuracy of this method,which can provide technical support for the minimally invasive spatium intermuscular approach surgery of lumbar spine in ultrasound assisted navigation.Methods:We selected 10 health volunteers in accordance with the inclusion and exclusion criteria.At first,all of the selectors did sagittal scaning of lumbar spine by using ultrasound check instrument(Korea Medison Accuvix A30)to locate spinous processes and mark them,then we did continuous Cross-sectional scanning of lumbar spine centered on the mark to track spatium intermusculare and observed its dynamic changes.Lastly,we freezed the image as measurement plane when cross-sectional scanned through the midpoint of the spinous process.In the image,we drew a posterior median line that passed the midpoint of the spinous process perpendicular to the abdominal wall,and another horizontal line that went through the external aperture of spatium intermusculare perpendicular to the posterior median line.Then,we measured the horizontal distance from the external aperture to the intersection of the two lines,recorded the distance from the external aperture of the gap between multifidus and longissimus to the posterior midline as “a”,the distance between the external aperture of the gap between longissimus and iliocostalis and the posterior midline as “b”,the distance from the external aperture of the gap between iliocostalis and quadratus lumborum to the posterior midline as “c” respectively.The superconducting MRI(Germany Siemens 1.5T)was used to do axial scanning of lumbar spine.In the image,the distances related above were measured by MRI at the level corresponded with the selected ultrasonic measurement plane.The difference of a,b and c between the two groups were compared by statistical software(SPSS).Results:1.The success rate was 100% for 100 transections of the gaps between multifidus and longissimus were explored by ultrasonography(100/100).At every level of spinous process of lumbar vertebra,the values of a measured by ultrasonography and the values measured by MRI were compared,and there was no statistically significant difference(P>0.05).2.The success rate was 40% for 40 transections of the gaps between longissimus and iliocostalis were explored by ultrasonography(40/100).3.The success rate was 24% for 24 transections of the gaps between iliocostalis and quadratus lumborum were explored by ultrasonography(24/100).4.At the L5 level,ultrasonography did not find the gap between the longissimus and iliocostalis and space between iliocostalis and quadratus lumborum.Conclusion 1.Ultrasound can be used to explore the spatium intermuscular of lumbar spine,with different success rate of exploration.2.For the gap between the multifidus and longissimus,the success rate of exploration was the highest.3.The success rate of exploring the gap between the longissimus and iliocostalis and the gap between iliocostalis and quadratus lumborum is not high.