Lumbosacral Trunk Research Articles

High-resolution metal artifact reduction MR imaging of the lumbosacral plexus in patients with metallic implants.

To assess the quality and accuracy of metal artifact reduction sequence (MARS) magnetic resonance imaging (MRI) for the diagnosis of lumbosacral neuropathies in patients with metallic implants in the pelvis. Twenty-two subjects with lumbosacral neuropathy following pelvic instrumentation underwent 1.5-T MARS MRI including optimized axial intermediate-weighted and STIR turbo spin echo sequences extending from L5 to the ischial tuberosity. Two readers graded the visibility of the lumbosacral trunk, sciatic, femoral, lateral femoral cutaneous, and obturator nerves and the nerve signal intensity of nerve, architecture, caliber, course, continuity, and skeletal muscle denervation. Clinical examination and electrodiagnostic studies were used as the standard of reference. Descriptive, agreement, and diagnostic performance statistics were applied. Lumbosacral plexus visibility on MARS MRI was good (4) or very good (3) in 92% of cases with 81% exact agreement and a Kendall's W coefficient of 0.811. The obturator nerve at the obturator foramen and the sciatic nerve posterior to the acetabulum had the lowest visibility, with good or very good ratings in only 61% and 77% of cases respectively. The reader agreement for nerve abnormalities on MARS MRI was excellent, ranging from 95.5 to 100%. MARS MRI achieved a sensitivity of 86%, specificity of 67%, positive predictive value of 95%, and negative predictive value of 40%, and accuracy of 83% for the detection of neuropathy. MARS MRI yields high image quality and diagnostic accuracy for the assessment of lumbosacral neuropathies in patients with metallic implants of the pelvis and hips.

Quantitative Assessment of Trunk Muscles Involvement in Patients with Myotonic Dystrophy Type 1 Using a Whole Body Muscle Magnetic Resonance Imaging

Objective: The aim of this study was to analyze the pattern of trunk muscles involvement through a muscle MRI, in relation to the clinical data of patients diagnosed with myotonic dystrophy type 1 (DM1). Materials and Methods: Patients with DM1 who visited the neurology department were enrolled (n = 19). In all patients, the fatty degeneration of the muscle MRI in the lower cervical, upper thoracic, middle thoracic, and lumbosacral spine extensor muscle group and trunk flexor muscle group was evaluated. Clinical data, including CTG repeats, spinal deformity were analyzed to find the correlations with the fatty degeneration of trunk muscles in the muscle MRI. Results: All DM1 patients who presented with very mild to severe functional status showed T1-weghted high intensity signals in the upper-thoracic spine extensor muscle group. The sum MRI score of the spine extensor muscle group showed a significant correlation with the 6-min walking test, and Cobb's angle. Conclusions: DM1 frequently affects the trunk muscles, even in the early stage of disease progression, regardless of disease severity or age of onset. Among the para-vertebral muscles, the selective involvement of spine extensor muscles may explain the cause of spinal deformities, which mirrors the functional status of DM1.

Anatomical organization and somatic axonal components of the lumbosacral nerves in female rabbits.

To determine the anatomical organization and somatic axonal components of the lumbosacral nerves in female rabbits. Chinchilla adult anesthetized female rabbits were used. Anatomical, electrophysiological, and histological studies were performed. L7, S1, and some fibers from S2 and S3 form the lumbosacral trunk, which gives origin to the sciatic nerve and innervation to the gluteal region. From S2 to S3 originates the pudendal nerve, whose branches innervates the striated anal and urethra sphincters, as well as the bulbospongiosus, ischiocavernosus, and constrictor vulvae muscles. The sensory field of the pudendal nerve is ∼1800 mm2 and is localized in the clitoral sheath and perineal and perigenital skin. The organization of the pudendal nerve varies between individuals, three patterns were identified, and one of them was present in 50% of the animals. From S3 emerge the pelvic nerve, which anastomoses to form a plexus localized between the vagina and the rectum. The innervation of the pelvic floor originates from S3 to S4 fibers. Most of the sacral spinal nerves of rabbit are mixed, carrying sensory, and motor information. Sacral nerves innervate the hind limbs, pelvic viscera, clitoris, perineal muscles, inguinal and anal glands and perineal, perigenital, and rump skin. The detailed description of the sacral nerves organization, topography, and axonal components further the knowledge of the innervation in pelvic and perinal structures of the female rabbit. This information will be useful in future studies about the physiology and physiopathology of urinary, fecal, reproductive, and sexual functions.

Variations in the course of the superior gluteal artery in relation to the lumbosacral plexus.

The course of the superior gluteal artery (SGA) as it passes through the lumbosacral plexus is variable. The variations of the arterial course in relation to the lumbosacral plexus have focused on statistical analysis, and it is limited arterial diversity. In this study, we investigated the positional relation between the SGA and the furcal nerve (FN): guide to segmentation of the lumbosacral plexus, arising from the L4, ie, the contribution to the femoral nerve, obturator nerve, and lumbosacral trunk. We could classify the pathway of the SGA into three types based on its positional relation to the FN. The SGA courses under the ramus from which the FN originates (Type A), under the ramus one segment below the origin of the FN (Type B), or between the obturator nerve and the lumbosacral trunk (Type C). The SGA pathway in Types A and B showed a cranial or caudal shift along with cranial or caudal deviation of the FN. In summary, the variation in the SGA pathway was correlated with cranial or caudal shift of the FN. Our findings indicate that variations of the SGA pathway are associated not only with arterial transformation, but also with diversity of the lumbosacral plexus.

Real-Time Ultrasound/MRI Fusion for Suprasacral Parallel Shift Approach to Lumbosacral Plexus Blockade and Analysis of Injectate Spread: An Exploratory Randomized Controlled Trial.

Fused real-time ultrasound and magnetic resonance imaging (MRI) may be used to improve the accuracy of advanced image guided procedures. However, its use in regional anesthesia is practically nonexistent. In this randomized controlled crossover trial, we aim to explore effectiveness, procedure-related outcomes, injectate spread analyzed by MRI, and safety of ultrasound/MRI fusion versus ultrasound guided Suprasacral Parallel Shift (SSPS) technique for lumbosacral plexus blockade. Twenty-six healthy subjects aged 21–36 years received two SSPS blocks (20 mL 2% lidocaine-epinephrine [1 : 200,000] added 1 mL diluted contrast) guided by ultrasound/MRI fusion versus ultrasound. Number (proportion) of subjects with motor blockade of the femoral and obturator nerves and the lumbosacral trunk was equal (ultrasound/MRI, 23/26 [88%]; ultrasound, 23/26 [88%]; p = 1.00). Median (interquartile range) preparation and procedure times (s) were longer for the ultrasound/MRI fusion guided technique (686 [552–1023] versus 196 [167–228], p < 0.001 and 333 [254–439] versus 216 [176–294], p = 0.001). Both techniques produced perineural spread and corresponding sensory analgesia from L2 to S1. Epidural spread and lidocaine pharmacokinetics were similar. Different compartmentalized patterns of injectate spread were observed. Ultrasound/MRI fusion guided SSPS was equally effective and safe but required prolonged time, compared to ultrasound guided SSPS. This trial is registered with EudraCT (2013-004013-41) and ClinicalTrials.gov (NCT02593370).

Application of internal iliac artery embolization and presetting abdominal aorta balloon for complicated pelvic fractures

Objective To evaluate the clinical outcome of bleeding control by preoperative embolization of internal iliac artery with DSA and intra-operative presetting abdominal aorta balloon, combine with the operation techniques of exposure, reduction and internal fixation of pelvic fracture through lateral-rectus approach. Methods From March 2012 to May 2015, 7 patients with type C3 pelvic fractures admitted to our department from March 2012 to May 2015, treated with preoperative embolization of internal iliac artery under digital subtraction angiography 2 h before surgery and presetting abdominal aorta balloon were retrospectively reviewed. There were 3 males and 4 females, with an average age of 34 years (range, 16 to 61 years). According to AO classification, all 7 cases belonged to type C3 (3.2: 5 cases; C3.3: 2 cases), including 5 cases with limb fracture, 2 cases with craniocere-bral trauma, 4 cases with pulmonary contusion, 2 cases with injury of abdominsal organs. Time from injury to operation was 19 days on average (10 to 33 days). Patients received damage control surgery treatment including bleeding control and temporary external fixation, and ipsilateral tractions with heavy weight, intensive care and corrections of general situation before operation. The fracture model was manufactured by 3D printing and fracture reduction was simulated on computer preoperatively. Embolization of internal iliac artery was performed in the side of severe displaced sacroiliac joint with DSA 2 hours preoperatively. Reduction was performed to stabilize anterior-posterior pelvic ring and acetabular fractures via the intraoperative lateral-rectus approach. And 2 cases were performed by temporary balloon occlusion of abdominal aorta (≤ 60 min) for bleeding control in reduction of in the side of sacroiliac joint fractures. Results All the 7 cases had undergone the operations successfully, and the operating time was from 135-320 min with blood loss from 440-3 350 ml. According to Matta radiological evaluation postoperatively, reduction of pelvic fracture was rated as anatomic in 5 cases, satisfactory in 2, without complications. All 7 cases were complicated with lumbosacral plexus injury or lumbosacral trunk injury at different degrees (M0 2 cases, M1 2 cases, M2 2 cases, M3 1 case). According to the BMRC scoring system, 5 cases had well recovered and the other 2 cases had no improvement after three months (M4 2 cases, M5 3 cases). Conclusion Surgical management of pelvic fracture through preoperative internal iliac artery embolization and intra-operative occlusion of abdominal aorta could effective control bleeding and achieve favorable conditions for reduction. Lateral-rectus approach can provide adequate exposure of the anterior and posterior ring, and this approach could also provide excellent visual control of reduction and fixation. Key words: Pelvics; Fractures, bone; Embolization, therapeutic

Unusual case of sciatic nerve and deep pelvic endometriosis with lumbosacral plexus spread presenting with muscular atrophy and foot drop

Endometriosis is an important disorder which affects women in the childbearing age group. In addition to the commonly observed intrapelvic sites, it can very rarely affect extrapelvic location such as the sciatic nerve. We describe an uncommon case of sciatic endometriosis leading to gross muscular atrophy and foot drop. The patient additionally had perineural extension of endometriosis along the ipsilateral lumbosacral trunk and coexisting intrapelvic endometrial implants in retrocervical area, uterosacral ligament, and urinary bladder wall.

Three-dimensional navigation for placement of percutaneous sacroiliac joint screws in internal fixation of sacroiliac complex injury

Objective To investigate the clinical results of three-dimensional navigation for placement of percutaneous sacroiliac joint screws in the internal fixation of sacroiliac complex injury. Methods A retrospective study was conducted of the 30 patients who had been treated for sacroiliac complex injury from March 2015 to January 2016 and fully followed up. They were 22 males and 8 females, aged from 25 to 63 years (average, 44.2 years). According to Tile classification for pelvic fractures, there were 14 cases of type B (type B1 in 6, type B2 in 6 and type B3 in 2), and 16 cases of type C (type C1 in 9, type C2 in 5, and type C3 in 2). Three cases complicated with preoperative injury to lumbosacral trunk were treated with anterior plate and percutaneous sacroiliac joint screws; the other 27 cases with internal fixation with percutaneous sacroiliac joint screws. The placement of screws was aided by three-dimensional navigation. The time for each screw placement and X-ray exposure was recorded intraoperatively. Postoperative reduction quality was assessed using Matta radiological criteria and Majeed criteria was used at the final follow-ups to evaluate the pelvic function. Results Altogether 36 sacroiliac joint screws were inserted in the 30 patients under three-dimensional navigation. The time for each screw placement ranged from 28 to 40 minutes (average, 33.2 minutes); the intraoperative X-ray exposure time ranged from 1.2 to 2.5 minutes (average, 1.4 minutes). No infection occurred at either incision or placement site. According to Matta radiological criteria, reduction was excellent in 16, good in 11 and fair in 3, giving an excellent to good rate of 90.0%. The follow-up time for the 30 patients ranged from 6 to 12 months (average, 10.6 months). At the final follow-ups, X-ray and CT three-dimensional reconstruction showed fine fracture union and no loosening or breakage of screws in all. By the Majeed criteria, the pelvic function was excellent in 17 cases, good in 8 cases, fair in 4 cases, and poor in one, giving a good to excellent rate of 83.3%. Conclusion Three-dimensional navigation for placement of percutaneous sacroiliac joint screws in internal fixation of sacroiliac complex injury can lead to precise placement, minimal invasion, safety and effectiveness. Key words: Sacroiliac joint; Wounds and injuries; Fracture fixation, internal; Bone nails; Surgery, computer-assisted

Robotic Excision of Suture Entrapment of the Lumbosacral Trunk

Nerve injury is a rare but serious complication of sacrospinous apical suspension procedures, occurring in up to 2% of cases. Injury can occur to the pudendal nerve, lumbosacral trunk and sciatic nerve. Symptoms commonly include severe refractory pain, paresthesias and motor deficit.

Inferior gluteal and other nerves associated with sacrospinous ligament: a cadaver study

Reported rates of gluteal pain after sacrospinous ligament fixation range from 12-55% in the immediate postoperative period and from 4-15% 4-6 weeks postoperatively. The source of gluteal pain often is attributed to injury to the nerve to levator ani or pudendal nerve. The inferior gluteal nerve and other sacral nerve branches have not been examined thoroughly as potential sources of gluteal pain. The purpose of this study was to further characterize anatomy of the inferior gluteal nerve and other nerves that are associated with the sacrospinous ligament from a combined gluteal and pelvic approach and to correlate findings to sacrospinous ligament fixation. Dissections were performed in female cadavers that had not been embalmed with gluteal and pelvic approaches. From a pelvic perspective, the closest structure to the superior border of the sacrospinous ligament midpoint was noted, and the sacral nerves that perforated the ventral surface of coccygeus muscle were examined. From a gluteal perspective, the closest distances from ischial spine to the pudendal, inferior gluteal, posterior femoral cutaneous, and sciatic nerves were measured. In addition, the closest distance from the midpoint of sacrospinous ligament to the inferior gluteal nerve and the origin of this nerve were documented. The thickness and height of the sacrospinous ligament at its midpoint were measured. Sacral nerve branches that coursed between the sacrospinous and sacrotuberous ligaments were assessed from both a pelvic and a gluteal approach. Descriptive statistics were used for data analysis. Fourteen cadavers were examined. From a pelvic perspective, the closest structure to the superior border of sacrospinous ligament at its midpoint was the S3 nerve (median distance, 3 mm; range, 0-11 mm). Branches from S3 and/or S4 perforated the ventral surface of coccygeus muscles in 94% specimens. From a gluteal perspective, the closest structure to ischial spine was the pudendal nerve (median distance, 0 mm; range, 0-9 mm). Median closest distance from inferior gluteal nerve to ischial spine and to the midpoint of sacrospinous ligament was 28.5 mm (range, 6-53 mm) and 31.5 mm (range, 10-47 mm), respectively. The inferior gluteal nerve arose from dorsal surface of combined lumbosacral trunk and S1 nerves in all specimens; a contribution from S2 was noted in 46% of hemipelvises. At its midpoint, the sacrospinous ligament median thickness was 5 mm (range, 2-7 mm), and its median height was 14 mm (range, 3-22 mm). In 85% of specimens, 1 to 3 branches from S3 and/or S4 nerves pierced or coursed ventral to the sacrotuberous ligament and perforated the inferior portion of the gluteus maximus muscle. Damage to the inferior gluteal nerve during sacrospinous ligament fixation is an unlikely source for postoperative gluteal pain. Rather, branches from S3 and/or S4 that innervate the coccygeus muscles and those coursing between the sacrospinous and sacrotuberous ligaments to supply gluteus maximus muscles are more likely to be implicated. A thorough understanding of the complex anatomy surrounding the sacrospinous ligament, limiting depth of needle penetration into the ligament, and avoiding extension of needle exit or entry point above the upper extent of sacrospinous ligament may reduce nerve entrapment and postoperative gluteal pain.

Somatomotor and sensory urethral control of micturition in female rats.

In rats, axons of external urethral sphincter (EUS) motoneurons travel through the anastomotic branch of the pudendal nerve (ABPD) and anastomotic branch of the lumbosacral trunk (ABLT) and converge in the motor branch of the sacral plexus (MBSP). The aim of the present study was to determine in female rats the contribution of these somatomotor pathways and urethral sensory innervation from the dorsal nerve of the clitoris on urinary continence and voiding. EUS electromyographic (EMG) activity during cystometry, leak point pressure (LPP), and voiding efficiency (VE) were assessed in anesthetized virgin Sprague-Dawley female rats before and after transection of the above nerve branches. Transection of the MBSP eliminated EUS EMG, decreased LPP by 50%, and significantly reduced bladder contraction duration, peak pressure, intercontraction interval, and VE. Transection of the ABPD or ABLT decreased EUS EMG discharge and LPP by 25% but did not affect VE. Transection of the dorsal nerve of the clitoris did not affect LPP but reduced contraction duration, peak pressure, intercontraction interval, and VE. We conclude that somatomotor control of micturition is provided by the MBSP with axons travelling through the ABPD and ABLT. Partial somatomotor urethral denervation induces mild urinary incontinence, whereas partial afferent denervation induces voiding dysfunction. ABPD and ABLT pathways could represent a safeguard ensuring innervation to the EUS in case of upper nerve damage. Detailed knowledge of neuroanatomy and functional innervation of the urethra will enable more accurate animal models of neural development, disease, and dysfunction in the future.

The origin variability of the iliolumbar artery and iatrogenic sciatica.

The iliolumbar artery (ILA) is a standard branch from the posterior trunk of the internal iliac artery. It is the only pelvic artery ascending from pelvic cavity. Current study comprises 171 cadavers dissection to assess the origin variability of ILA. The present study identified the incidence of the ILA origin variability in Caucasian population which also clarified the iliolumbar variability in males and females. The current study shows that the ILA arises from the common iliac artery in 2%, from the external iliac artery in 0.3% and from the internal iliac artery in 13.8% either from its dorsal or dorsomedial aspects in 1 and 12.8%, respectively. The common, external and internal iliac arteries are defined as a high (early) origin and occurred in 16.1%. The posterior trunk of the internal iliac artery is the most common origin of the ILA found to be in 77.9%. Occasionally, it also arose from the superior gluteal artery (0.7%) and the sciatic artery (0.3%). Furthermore, the ILA arises from the anterior trunk indirectly as from the inferior gluteal artery in 0.3%. The ILA arising from the superior or inferior gluteal artery or from the sciatic artery is defined as a low (delayed) origin and occurred in 1.3%. In contrast, the ILA was 4.7%. Consequently, variability of the ILA leads to vascular variability of the lumbosacral trunk of the sciatic nerve. Clinicians have to be aware of these variations to avoid unnecessary ligation to prevent sciatic neuropathy.

The furcal nerve revisited.

Atypical sciatica and discrepancy between clinical presentation and imaging findings is a dilemma for treating surgeon in management of lumbar disc herniation. It also constitutes ground for failed back surgery and potential litigations thereof. Furcal nerve (Furcal = forked) is an independent nerve with its own ventral and dorsal branches (rootlets) and forms a link nerve that connects lumbar and sacral plexus. Its fibers branch out to be part of femoral and obturator nerves in-addition to the lumbosacral trunk. It is most commonly found at L4 level and is the most common cause of atypical presentation of radiculopathy/sciatica. Very little is published about the furcal nerve and many are unaware of its existence. This article summarizes all the existing evidence about furcal nerve in English literature in an attempt to create awareness and offer insight about this unique entity to fellow colleagues/professionals involved in spine care.

In lumbosacral plexus injuries can we identify indicators that predict spontaneous recovery or the need for surgical treatment? Results from a clinical study on 72 patients

BackgroundPost-traumatic lumbosacral plexus injuries seem to be rare events, spontaneously recovering in high percentage: as surgery is often challenging and results in poor outcome, many Authors have advocated conservative treatment only. Nevertheless surgery should not be ruled out: in invalidating injuries, it can restore basic function in the lower extremities.Therefore, it might be necessary to establish guidelines for the management and the indication to surgery in such cases.This study aims to identify indicators predicting spontaneous recovery or the need for surgery.MethodThe clinical and radiological data of 72 patients with a post-traumatic lumbosacral plexus injury were reviewed. A follow up equal or superior to 3 years is available in 42 cases.ResultsLumbosacral plexus injuries mostly occurred during road accidents. The incidence of associated lesions was relevant: bone injuries were found in 85% of patients, internal lesions in 30% and vascular injuries in 8%.Lumbosacral trunk and sacral plexus palsies were the most frequent injury patterns.Root avulsions were revealed in 23% of cases and only in sacral plexus and complete lumbosacral plexus injuries: L5 and S1 were the roots more prone to avulsions.About 70% of cases recovered spontaneously, mostly in 18 months. Spontaneous recovery was the rule in lumbar plexus and lumbosacral trunk injuries (where root avulsions never occurred) or in sacral and complete lumbosacral plexus palsies due to compression injuries.The causative mechanism correlated with the injury pattern, the associated bone injury being often predictive of the severity of the nerve injury.Lumbosacral plexus injuries occurred in car crashes were generally associated with fractures causing compression on the nerves, thus resulting in injuries often amenable of spontaneous recovery.Motorcycle accidents implied high kinetic energy traumas where traction played an important role, as the high percentage of sacroiliac joint separations demonstrated (found in more than 50% of cases and always associated to root avulsions).Loss of sphincteral control and excruciating leg pain were also invariably associated with avulsions.ConclusionsClinical and radiological data can help to predict the occurrence of spontaneous recovery or the need for surgery in post-traumatic lumbosacral plexus injuries.

Accurate Needle Placement - A Must For a Safe and Effective Bone Marrow Biopsy Procedure: An Anatomical and CT Based Cadaver Study

IntroductionBone marrow examination is an essential and commonly performed bedside procedure in diagnosis and staging of hematological malignancies and benign hematological disorders. Although when performed on the posterior superior iliac spine(PSIS), it is considered a safe procedure with minimal complications, cases of excessive bleeding , hematoma formation, injury to neurovascular structures, retroperitoneal and intraperitoneal hemorrhage, pseudo aneurysm formation and gluteal compartment syndrome have been reported. Cases of retroperitoneal hemorrhage are presumed to occur due to penetration of the needle through the iliac crest indicating that accurate placement and angulation of the biopsy needle is critical to avoid iatrogenic complications. Bone marrow biopsy has been described in various publications and text books. However, standardized technique for positioning the biopsy needle and its penetration orientation are lacking. Various authors have described the correct needle placement and orientation as perpendicular to the bone or pointing towards the anterior superior iliac spine (ASIS) but most of the studies do not specify angulation of the needle. These methods appear to be extrapolated from personal experience and, to date, an evidence based approach for needle angulation has not been described. We present a comparison of different described approaches to perform bone marrow biopsy relative to injury to critical structures should the needle penetrate the inner bone cortex. This study compares the two most commonly used PSIS biopsy approaches that advance the needle towards: 1. The Umbilicus (Medial Approach) 2. Ipsilateral ASIS (Lateral Approach). MethodsThe study was done on cadavers in the dissection laboratory at the Albert Einstein College of Medicine. The procedure was performed by Attendings and Fellows in Hematology Division who are experienced in performing bone marrow biopsy. Manual Jamshidi needles or powered bone marrow device were used. Anatomy professors helped identify the landmarks and performed dissections after biopsy procedures. The Radiology Department assisted with performing and reading the CT scans of the pelvises.The first phase of study involved placing two dissected cadavers with intact pelvises in prone and lateral positions. Bone marrow needle was placed perpendicular to the PSIS and, during penetration, the direction was changed toward the umbilicus for the Medial Approach and towards the ASIS during the Lateral Approach. A bone marrow biopsy was obtained. Subsequently, using the same needle track, the needle was deliberately pushed through the inner ilial cortex to assess the resultant potential for injury. Keeping the needles in situ, metal wire probes were inserted via the needle for better visualization. The cadavers were further dissected to identify injury to neurovascular bundles and adjacent structures.In the second phase, bone marrow biopsy was performed on two intact cadavers. The needles with inserted probes were left in situ to mark different angulations. The cadavers were then scanned and dissected to identify penetrated structures and closely related neurovascular bundles that were at risk had the orientation varied slightly. ResultsDissections and CT scan imaging showed that Lateral Approach was less likely to cause injury to significant neurovascular structures and penetrate the sacroiliac joint in comparison to the Medial Approach. Using the Medial Approach, in the event of penetration of inner cortex, we documented injury to the sacro-iliac joint, femoral nerve, common iliac vessels and mesentery of the sigmoid colon. The needle was observed in close proximity to the iliolumbar vein and artery and the lumbosacral trunk. Using the Lateral Approach, the structures adjacent to the needle were limited to the iliacus muscle and the lateral cutaneous branch of femoral nerve. The lateral approach had the added benefit of more consistent orientation since the relationship of the ASIS to the PSIS is both consistent and palpable whereas the location of the umbilicus may vary.We suggest that the safest way to perform a bone marrow biopsy is to advance the needle in a perpendicular direction to reach the PSIS. Once the needle penetrates the outer cortex of the bone, the direction should be changed pointing towards the ipsilateral ASIS. We believe that this procedure will obviate complications reported in the literature.▪▪ Disclosures:No relevant conflicts of interest to declare.

Identification of sacral plexus at robot-assisted nerve-sparing radical hysterectomy with extended lymphadenectomy

목적: Demonstrate a new instrument, technique or procedure 방법: We use da Vinci system to demonstrate surgical technique of identification of Sacral plexus in part of Robot assisted nerve sparing radical hysterectomy with extended lymphadenectomy for early cervical cancer. It necessary to understand anatomy of deep sacral plexus to prevent the nerve injury in case of extensive lymphadenectomy in high risk cervical cancer. The sacral plexus is formed by the union of the lumbosacral trunk (from the anterior rami of L4 and L5) and the anterior rami of the first, second, third, and fourth sacral nerves. The nerves forming the sacral plexus converge to the lower part of the greater sciatic foramen and unite to form a flattened band, sciatic nerve. The clinical significant of sacral plexus is that an injury to the sacral plexus, leaves the patient with a deficit in the sensation and/or movement and experience neuropathic pain in the lower limb supplied by the corresponding nerve(s) affected. After extended lymphadenectomy, we could confirm the pelvic anatomy more clearly including superior hypogastric plexus, promontory, lower part of aorta, common iliac vessels, hypogastric nerve communicating with parasympathetic nerves, and vesical branches of inferior hypogastic plexus. And sacral plexus, lumbosacral trunk, S1, S2 and S3. 결과: No intraoperative complications or postoperative nerve injury that required treatment occurred. 결론: It would be expected in sacral plexus identifying extended lymphadenectomy that the more number of lymph nodes, metastatic nodes and therapeutic benefits for improvement of survival. However, it needs to evaluate long term survival benefit and functional benefits about identifying sacral plexus extended lymphadenectomy

Compression of the lumbosacral trunk and S1 nerve root by calcific posterior branches of the internal iliac artery: A potential source of sciatic pain.

The purpose of this study is to describe how lumbosacral nerve roots in the pelvis can be compressed by calcific branches of the internal iliac artery. Sciatic pain caused by nerve root compression can be painful and debilitating. Compression of nerve roots comprising the sciatic nerve can occur at their immediate exit from the spinal cord or anywhere along their length. Identifying the precise location of nerve root compression is critical for effective treatment of clinical signs and symptoms. This study of 38 cadaveric hemipelvis dissections provides evidence to support that calcific branches of the internal iliac artery may compress and deform underlying nerve roots. This deformation suggests nerve compression. Specificially, when the posterior division of the internal iliac artery or superior gluteal artery contains calcific plaque, they form a visible impression on the nerves they course over in approximately 85.7% of the time. In this study, the lumbosacral trunk is the most commonly compressed nerve root in the pelvis, but the S1 nerve root can be affected as well. When the blood vessels lacked calcific plaque, they did not produce visible deformation of the underlying nerves. Understanding this potential mechanism of nerve compression in the pelvis has clinical significance for patients with sciatic pain.

Morphometry of the Iliolumbar Artery and the Iliolumbar Veins and Their Correlations with the Lumbosacral Trunk and the Obturator Nerve

To reveal the variations of the iliolumbar artery and the iliolumabar veins and their correlation with the surrounding important structures. We dissected the iliolumbar region bilaterally in 20 formalin-fixed adult cadavers. The diameter of the iliolumbar artery at its origin, its length up to the branching point, the distance between the iliolumbar artery and the inferior margin of the fifth lumbar vertebra and the distance between the iliolumbar artery and the bifurcation point of the common iliac artery, were measured. The pattern of drainage, the dimensions, the points of confluence with the common iliac vein and the obliquity of the iliolumbar vein were noted. The correlation between the iliolumbar artery and the veins to the obturator nerve and the lumbosacral trunk was recorded. The iliolumbar artery originated from the posterior trunk of the internal iliac artery or from the internal iliac artery. The mean diameter of the iliolumbar artery, at its origin, was 3.5±0.5 mm. The mean distance between the origin of the iliolumbar artery and the bifurcation point to the iliac and the lumbar branches was 12.2±5.5 mm. The distance between the origin of the iliolumbar artery and the lower edge of the fifth lumbar vertebra was 43.2±11.6 mm. The distance between the origin of the iliolumbar artery and the bifurcation point of the common iliac artery was 38.7±10.6 mm. The mean distance of the iliolumbar veins from the inferior vena cava, overall, was 35± 9.9 mm. The mean width of the mouth of the iliolumbar vein was10.7 ± 5.1 mm and the mean angle of obliquity of the vein with respect to the long axis of the common iliac vein was 75.50. The tributaries which drained into the main iliolumbar vein were variable. The iliolumbar artery passed anterior in 70% and it passed posterior to the obturator nerve in 30%. The veins were lying anterior to the obturator nerve in 45% and they were lying posterior in 55%. The multiple tributaries which drained into the iliolumbar vein relation of the tributaries were variable, few passed anterior and few passed posterior. The iliolumbar artery was seen anterior to the lumbosacral trunk in 30%, it was posterior in 54%, it was cleaved in 8% and the branches of the artery were passing on either side of the lumbosacral trunk to enclose it like a clasp in 8%. The veins were anterior to the lumbosacral trunk in 40% and they were posterior in 60%. The anatomical features of the iliolumbar artery, the iliolumbar veins and their correlation with the anatomical landmarks, which were presented here, would be helpful in decreasing the iatrogenic trauma to the neurovascular structures in the iliolumbar region.

An unusual formation of sciatic nerve

Sciatic nerve is the largest nerve and a branch of sacral plexus that controls hamstrings and all muscles of the lower limb below the knee. We are reporting a bilateral variant formation of the sciatic nerve found in a male human cadaver. The commencement of single sciatic nerve trunk formation was found to be in the lower gluteal region instead of the pelvic region. All the roots of the sciatic nerve, namely, the lumbosacral trunk (L4, L5), S1, S2, and S3 were observed to remain separate up to the lower part of the gluteal region. Incidence of this variation in general population needs to be investigated so as to create awareness among surgeons and anesthetists about the degree and extent of variation in sciatic nerve formation. Complete sciatic nerve blockages will fail even after multiple punctures and attempts if the sciatic nerve is present as separately sheathed bundles until the lower gluteal level.

Dorsal root activity evoked by stimulation of vagina–cervix–uterus junction in the rat

In the present study, we characterized the evoked electrical activity from T13 to S2 dorsal roots (DRs) during glass probe-stimulation of the vagina–cervix–uterus junction (VCUJ) of female Wistar rats. The results showed that gentle stimulation of VCUJ evoked high-amplitude electrical activity in L3 and L6 DRs. Hypogastric or pelvic nerve transection failed to abolish this activity. L6–S1 spinal trunk transection abolished the high-amplitude electrical activity evoked in L6 DR, while transection of the lumbosacral trunk blocked the high-amplitude electrical activity evoked in L3 DR. These data suggest that during copulation, penile intromission likely activates the low-threshold sensory receptors of the VCUJ, thereby evoking sensory neural activity that enters the spinal cord via L3 and L6 dorsal roots, whose axons travel through the lumbosacral trunk and pudendal nerve.