Search

Introduction: Male genital dysfunction was recognized as a complication following anterior approach lumbar surgery. Disruption of efferent sympathetic pathways such as the abdominal aortic plexus (AAP) and superior hypogastric plexus (SHP) which lied pre-abdominal aorta and iliac artery had been thought as the main reason. Though there were some clinical reports of retrograde ejaculation, the applied anatomic study of the autonomic nerve anterior to the lumbar was little. The purpose was to find out a lumbar surgery approach which was ejaculation preservation through the detailed study of the anatomy and histology observation of the autonomic nerve anterior to the lumbar vertebrae., Methods: The lumbar region of ten male cadavers was dissected and analyzed. We investigated the relationship between the peritoneum and abdominal aorta, iliac artery and sacral promontory fascia, as well as the trend and distribution of the autonomic nerve and SHP anterior to the L5-S1. We also observed the distribution of autonomic nerve at retroperitoneum through hematoxylin and eosin (HE)-stained tissues pre-aorta, para-aorta, and pre-vertebrae sacrales., Results: Superior hypogastric plexus, which deviated to left, located in a triangle formed by the common iliac arteries and its bilateral branches, its truck sited anterior to the lumbarsacral space in seven cases (70%), and anterior to sacrum in three cases (30%); at the aortic bifurcation, SHP strided over left iliac artery from left-hand side, then located in front of sacrum in four cases (40%), and sifted to the left at the lumbar sacral promontory in six cases (60%); from both anatomic and histological view, the autonomic nerve plexus lying in an fascia layer of retroperitoneum., Conclusion: At the anterior approach lumbar surgery of trans-peritoneum, we should choose the right-hand side incision; the SHP should be pushed aside carefully from right to left along intervertebral disc. The accurate surgical plane was at the deeper layer of autonomical nerve fascia; we also could lift the complete autonomical nerve layer which lies behind the aorta and lumbar sacral promontory, so that the autonomic nerve could be preserved.

Objective: To develop a novel method of spinal pedical stereotaxy by reverse engineering and rapid prototyping techniques, and to validate its accuracy by experimental and clinical studies., Methods: A 3D reconstruction model for the desired lumbar vertebra was generated by using the Mimics 10.11 software, and the optimal screw size and orientation were determined using the reverse engineering software. Afterwards, a drill template was created by reverse engineering principle, whose surface was the antitemplate of the vertebral surface. The drill template and its corresponding vertebra were manufactured using the rapid prototyping technique., Results: The accuracy of the drill template was confirmed by drilling screw trajectory into the vertebral biomodel preoperatively. This method also showed its ability to customize the placement and size of each screw based on the unique morphology of the lumbar vertebra.The drill template fits the postural surface of the vertebra very well in the cadaver experiment. Postoperative CT scans for controlling the pedicle bore showed that the personalized template had a high precision in cadaver experiment and clinical application. No misplacement occurred by using the personalized template. During surgery, no additional computer assistance was needed., Conclusions: The authors have developed a novel drill template for lumbar pedicle screw placement with good applicability and high accuracy. The potential use of drill templates to place lumbar pedicle screws is promising. Our methodology appears to provide an accurate technique and trajectory for pedicle screw placement in the lumbar spine.

Objective: To provide anatomic data for reducing lumbar plexus nerve injury., Methods: The applied anatomy of lumbar plexus was studied by 15 formaldehyde-preserved cadavers, two groups of sectional images of lumbar segment and three series of virtual chinese human dataset., Results: Arrangement of the lumbar nerve was regular. From anterior view, lumbar plexus nerve arranged from lateral to medial from L2 to L5; from lateral view, lumbar nerve arrange from ventral to dorsal from L2 to L5. The angle degree between the lumbar nerve and lumbar increased from L1 to L5. The lumbar plexus nerve was revealed to be in close contact with transverse process. By sectional anatomy, all parts of the lumbar plexus nerve were located in the dorsal third of the psoas major. The safety zone of the psoas major to prevent nerve injuries was ventrally 2/3., Conclusions: Psoas major can be considered as surgery landmark when expose the lateral anterior of lumbar by incising the psoas muscle. Incising the psoas muscle ventral 2/3 can prevent lumbar plexus injury. Transverse process can be considered as landmark for the position of lumbar plexus in operation.

Objective: To study the anatomy of veins of the lower lumbar spine and provide the anatomic basement for laparoscopic lumbar surgery., Methods: A total of 15 formaldehyde-preserved cadavers were studied with special attention to the variety and surrounding structure of ascending lumbar vein (ALV) and iliolumbar veins (ILV), and their relationship with lumbar plexus., Results: ALV and ILV can be found on every sides, which have four variants including separate entry and common entry. The ascending vein and iliolumbar vein separately enter common iliac vein in 18 cases, and as a common stem enter the common iliac vein in 12 cases. Retracting common iliac vein medially both the ascending lumbar and the iliolumbar veins are always at risk of avulsion on exposure of the disc space. The injury of obturator nerve and lumbosacral trunk of lumbar plexus should be avoided., Conclusion: Awareness of these anatomic variation can prevent the hemorrhage and be helpful for the surgeon in performing a careful ligation of these veins before medial retraction of the common iliac vein. Our findings emphasize the need for proper dissection of ALV and ILV before ligature during exposure of the lower lumbar spine.