Sacral Foramina Research Articles

The classification of sacral foramina in a South African sample using cadaveric and osteological remains

Sacroiliac (SI) joint fixation is a technique used for SI joint fractures, SI joint dislocations and sacral fractures. Sacral screws can be placed either into the S1 or the S2 vertebrae if S1 is insufficient. Malpositioning of the screws is a common surgical complication as sacral variations exists amongst populations. Complications associated with the misposition of screws can lead to injury of the sacral venous plexus, iliac vessels, or sacral nerve roots. Therefore, this study aimed to evaluate sacral variations in a South African sample by determining distances between the first and second sacral foramina and classifying the common types of sacra found.A quantitative cross-sectional comparative study was conducted. One hundred and twenty (n = 120) dry human sacra and 11 formalin-fixed cadavers were measured to determine the linear distances between the first two anterior and posterior sacral foramina. Additionally, the dry human sacra were classified according to Mahato's classification system. A cadaver SI joint fixation simulation was performed by an orthopaedic surgeon.The mean sacral promontory height was found to be 31.81 mm and 37.52 mm in osteological and cadaver specimens, respectively. The mean anterior pedicle height was significantly different for the left (18.81 mm) and right (21.67 mm) side measurements. A statistically significant difference was found between cadavers and osteological samples for all measurements taken. In the osteological sample, ancestry and age mostly influenced the variations noted.Using Mahato's classification system, sacra with five sacral segments, auricular surfaces extending from the superior part of S1 to the middle of S3 and no accessory L5/S1 articulations had the highest prevalence of 59.17 %.The South African sample exhibited similarities but did not fully compare to other populations. The results in this study should be considered as a reference for surgeries involving the SI joint and sacral foramina. However, where possible, the exact anatomy with possible variations of the patient should be evaluated preoperatively using X-rays and angiograms.

Clinical Anatomy of the Sacral Nerve Roots and Its Relevance to Their Reconstruction After Sacrectomy.

En bloc sacrectomy is associated with sacral root transection causing loss of urinary bladder, rectum, and sexual function. The aim of the study was to determine the position of the pudendal branches (sensorimotor) and pelvic splanchnic nerves (parasympathetic) on the sacral roots relative to the sacrum, and the minimal and maximal defects in the sacral roots that can be reconstructed by grafting after various types of sacrectomy. Five cadaveric pelves were dissected bilaterally. The lengths and widths of the S1-S4 roots and their branches were measured. Then, the minimal and maximal defects between the proximal and distal stumps of the sacrificed roots were measured following 3 models of sacrectomy (below S2, below S1, and total sacrectomy). The mean distance of the splanchnic nerves from the S2 and S3 anterior sacral foramina was 17.7 ± 7.3 and 23.6 ± 11.1 mm, respectively, and the mean distance of the pudendal S2 and S3 branches was 36.8 ± 13.7 and 30.2 ± 10.8 mm, respectively. The mean widths of the S2 and S3 roots were 9.3 ± 1.9 and 5.4 ± 1.2 mm, respectively. The mean maximal defects in S2 and S3 roots after various types of sacrectomies were between 61.8 ± 16.3 and 100.7 ± 14.3 mm and between 62.7 ± 20.2 and 84.7 ± 25.1 mm, respectively. There were no statistically significant differences between sides or sexes for all obtained measurements. The reconstruction of the S2-S3 roots is anatomically feasible after partial or total sacrectomies in which the resection of the soft tissue does not extend further than approximately 1.5 to 2 cm ventrally from the sacrum.

Dissimilar Planes and Approaches with Common Neural Targets - A Cadaveric Evaluation of Three Different Ultrasound-guided Fascial Plane Blocks for Lumbar Plexus Nerves.

The lumbar plexus (LP) is a group of nerves located at the fourth lumbar vertebra level, between the anterior two-thirds and posterior one-thirds of the psoas muscle. In this study, the researchers aimed to investigate the spread of latex in injections of LP, suprainguinal fascia iliaca, and circum-psoas planes to assess the different regional techniques for blocking LP nerves (LPNs). The study involved performing ultrasound-guided injections of three different colored latexes in six cadavers. The researchers observed and compared the spread of latex in each plane by taking cross sections at the levels of L4, anterior superior iliac spine (ASIS), and sacral foramina (SF). The spread of latex and LPN staining was documented and analyzed through photography. The results showed that the latex spread within the psoas muscle and fascia iliaca plane (FIP) during LP injections, whereas suprainguinal fascia iliaca injections showed latex dissemination in the FIP at both ASIS and SF levels. On the other hand, circum-psoas injections spread beneath the iliopsoas fascia at both levels and medially toward the external iliac vessels. Despite this spread, there was no communication between the three planes, and there was no mixing of latex from the different injections at any level. There are distinct fascial planes, for the three approaches, with no communication between them. While latex diffused from LP plane to FIP, no mixing of dye was observed and also the reverse could not be achieved. These findings suggest that different regional techniques for blocking LPNs have their unique planes of action.

Second generation robotic-assisted percutaneous balloon sacroplasty

Abstract Sacroplasty is one of the surgical modalities described in the treatment of sacral insufficiency fractures that don’t respond to non-operative treatment. While the percutaneous procedure is generally done under sedation, complications can arise from cement leakage into the spinal canal and sacral foramina. We present a case of Robotic-Assisted Percutaneous Balloon Sacroplasty in a patient with unilateral sacral insufficiency fracture using the MazorX stealth edition. A 55-year-old female presented with a left-sided sacral insufficiency fracture which was not responding to non-operative treatment. She underwent Robotic-Assisted Percutaneous Balloon Sacroplasty using the robotic arm and navigation capabilities of the MazorX stealth edition. About 9 mL of bone cement with hydroxyapatite was injected into the S1 body and left ala. The patient was mobilized post-operatively with minimal pain, 2 h after the procedure. Robotic assistance in percutaneous balloon sacroplasty ensures proper tracks for injection of bone cement with reduced chances of cement leakage.

Analysis of Eligibility of the S1 Corridor for the Trans-Sacral Screw Placement in Geriatric Patients

Abstract Background Minimal-invasive placement of a trans-sacral screw represents an increasingly popular method of fixation for Fragility Fractures of the Pelvis (FFP), with variable upper sacral anatomy representing the main challenge. Little is known about the variability of sacral anatomy in the geriatric population and the potential effect of osteoporosis on the upper sacral anatomy and thus S1 corridor morphology. Aims To examine the eligibility (>12 mm) of the S1 corridor for the trans-sacral screw placement in a geriatric population and to analyse what pelvic dysmorphism signs might serve as predictors for an ineligible S1 corridor. Methods We analysed S1 corridor in pelvic CT scans of 107 geriatric patients without history of fracture or other pelvic pathology. First, the eligibility for the trans-sacral screw placement was determined by measuring the width and the height of the central portion of the S1 corridor. Then, pelvises were examined for signs of dysmorphism. The correlation of these signs with the ineligible S1 corridor was analysed. Results In our geriatric population with average age of 79,55 ± 8.79 years (male : female 0.88) 44% of S1 corridors were not eligible for a trans-sacral screw. In this ineligible group the height was shown to be a more significant limiting dimension (90,9%), compared to the width in 68,2% (p<0.05). Mamillary processes, not recessed sacrum and dysmorphic sacral foramina were present in 38,3%, 34,6%, and 26,2% respectively, with not recessed sacrum demonstrating a significant correlation with a too narrow S1 corridor (p<0.05). Conclusion The analysed geriatric population demonstrates a high prevalence of a too narrow S1 corridor, which makes a placement of a trans-sacral screw risky or even impossible. The height of the S1 corridor represents the main limiting factor with a dysmorphism sign of a not recessed sacrum being a significant predictor for the ineligible S1 corridor.

Incidence of Suboptimal Fluoroscopic Outlet Imaging of the Sacrum and Pelvic Retroversion Necessary for Optimal Views.

To estimate the prevalence of suboptimal fluoroscopy of sacral outlet images due to anatomic and equipment dimensions. Pelvic retroversion is hypothesized to mitigate this issue. In silico simulations using retrospectively collected computed tomography (CT) data from human patients. Level I trauma center. Adults with OTA/AO 61 pelvic ring disruptions treated with posterior pelvic fixation between July and December 2021. C-arm tilt angles required to obtain 3 optimal fluoroscopic sacral outlet images, defined as vectors from pubic symphysis to S2 and parallel to the first and second sacral neural foramina, were calculated from sagittal CT images. A suboptimal view was defined as collision of the C-arm radiation source or image intensifier with the patient/operating table at the required tilt angle simulated using the dimensions of 5 commercial C-arm models and trigonometric calculations. Incidence of suboptimal outlet views and pelvic retroversion necessary to obtain optimal views without collision, which may be obtained by placement of a sacral bump, was determined for each view for all patients and C-arm models. CT data from 72 adults were used. Collision between patient and C-arm would occur at the optimal tilt angle for 17% of simulations and at least 1 view in 68% of patients. Greater body mass index was associated with greater odds of suboptimal imaging (standard outlet: odds ratio [OR] 0.84, confidence interval [CI] 0.79-0.89, P < 0.001; S1: OR 0.91, CI 0.87-0.97, P = 0.002; S2: OR 0.85, CI 0.80-0.91, P < 0.001). S1 anterior sacral slope was associated with suboptimal S1 outlet views (OR 1.12, Cl 1.07-1.17, P < 0.001). S2 anterior sacral slope was associated with suboptimal standard outlet (OR 1.07, Cl 1.02-1.13, P = 0.004) and S2 outlet (OR 1.16, Cl 1.09-1.23, P < 0.001) views. Retroversion of the pelvis 15-20 degrees made optimal outlet views possible without collision in 95%-99% of all simulations, respectively. Suboptimal outlet imaging of the sacrum is associated with greater body mass index and sacral slope at S1 and S2. Retroversion of the pelvis by 15-20 degrees with a bump under the distal sacrum may offer a low-tech solution to ensure optimal fluoroscopic imaging for percutaneous fixation of the posterior pelvic ring. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Sacroiliac Joint Denervation-A Novel Approach to Target Sacral Lateral Branches: A Practical Approach.

Sacroiliac joint (SIJ) pain is a relatively common cause of low back pain. Percutaneous radiofrequency (RF) techniques for SIJ are limited to ablation of the posterior SIJ innervation. Different techniques have been described for SIJ radiofrequency ablation, including conventional thermal, cooled RF, pulsed RF, bipolar RF, and specialized tip RF needle (i.e., multi-tined); however, additional costs may limit these applications. This new technique for SIJ denervation uses anatomical landmarks and a single RF cannula. Two spinal needles are placed lateral to the posterior S1 and S2 sacral foramina; then, with caudal tilt we get a coaxial view of the sacral bone, we advance an 18-G curved 15-mm active tip RF cannula just lateral to the aligned finder needles. Ablation is performed, and then the RF cannula is retracted 2cm and ablation is repeated for a total of four lesions. The two spinal needles placed lateral to the posterior sacral foramina S1 and S2 guide the final needle in the posterior aspect of the sacrum, lateral to the sacral foramina, where the lateral sacral branches are located. We introduce a cost and time efficient technique to perform radiofrequency ablation of the sacral lateral branches using a single RF needle. This technique utilizes the sacrum's reliable anatomy and angulation and maximizes the surface area of the active tip lesioning. This technique creates a strip lesion lateral to the sacral foramina and reduces time and cost efficacy compared to several of the other techniques and/or commercially available special devices designed for sacroiliac denervation.

Effect of Sacral Erector Spinae Plane Block on Postoperative Analgesia in Perianal Surgeries: A Randomised Controlled Trial

Introduction: Sacral nerves emerge through sacral foramina and traverse below the multifidus muscle. Hence, blocking this myofascial plane can provide postoperative analgesia in the perianal region by blocking the sacral nerves supplying it. Aim: To study the effect of Sacral Erector Spinae Plane Block (SESPB) on postoperative pain and postoperative analgesic requirement in perianal surgeries. Materials and Methods: A randomised controlled trial was done with 60 patients who were randomly allocated into two groups (30 in each group). Group 1 patients received no intervention, whereas Group 2 received bilateral SESPB. The Visual Analogue Scale (VAS), opioid requirement, first analgesic demand, and additional analgesic requirement were compared between the two groups. The qualitative data was analysed by Student’s t-test, whereas the quantitative data was analysed using the Chi-square test. A p-value of &lt;0.05 was considered statistically significant. Results: Around 18 (60%) of the participants in group 1 were males, whereas group 2 consisted of 15 (50%) males. The mean age in group 1 was 40.7±11.5 years, whereas it was 43.6±12.7 years in group 2. The means of BMI were similar in both groups. The mean VAS score of group 1 was 3.19±0.23, whereas it was 2.37±0.25 in group 2. The first analgesic requirement was significantly delayed, and total tramadol requirement was lower in group 2 compared to group 1. Four patients from group 1 (control group) required inj. diclofenac sodium additionally. Conclusion: Bilateral SESPB provided good postoperative analgesia in patients who underwent perianal surgery. The total analgesic requirement was also found to be lower with this block. Hence, it can be considered a modality for perianal surgeries.

A Complete Non-fusion of Sacral Spines- a Rare Anomaly: A Case Report

Background: Human sacrum is a large triangular bone formed by fusion of five separate sacral vertebrae and their intervertebral disc. The dorsal surface of sacrum presents triangular sacral canal formed by fusion of sacral vertebral foramina. The opening present at the caudal end of the sacral canal is known as sacral hiatus. Sacral hiatus is formed due to failure of fusion of lamina and spinous process of fifth or fourth sacral vertebrae. Spina bifida occulta is a condition resulting due to incomplete fusion of neural arch of vertebrae, mainly in lumbosacral region. When the condition of spina bifida occulta occurs in the sacrum, the level of non-closure becomes variable. Materials and Methods: A dry human sacrum with full agenesis of the dorsal wall of the sacral canal was identified during regular osteology demonstration lessons for undergraduate BAMS students at Department of Sharir Rachana (Anatomy), Ayurveda Campus, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal. Non-metric differences in spines were thoroughly examined. Results and Discussion: Spina bifida is the generic term for range of discrete defects of neurulation and subsequent vertebral formation. The various forms of neural tube and vertebral defects have been reported such as craniorachisis, anencephaly and myocele. In this case a spine with complete sacral spina bifida occulta was discovered. The posterior laminae of all sacral vertebrae were completely unfused in this specimen. It's more likely that the sacral region was a groove than a canal. There were no additional abnormalities discovered. Many studies on incidence of spina bifida occulta have been published with mixed results. The frequency reported by researchers and population varies substantially. Conclusion: The complete agenesis of the dorsal wall of the sacral canal in these variants is critical for diagnosing lower back pain, sciatica, and caudal regression syndrome, as well as avoiding problems from caudal epidural block and other spinal procedures, such as screw placement for spinal fusion.

Pediatric presacral tumors with intraspinal extension: a rare entity with diagnostic challenges.

The presacral space is a potential space located between the rectum and the lumbosacral spine. It contains various primitive germ cell types that serve as the origin for a range of tumors. Imaging is crucial in characterizing, assessing the extent of and evaluating the treatment response to these tumors. We report a series of six cases of pediatric presacral tumors with intraspinal extension, including an immature sacrococcygeal teratoma (Altman type II), a malignant sacrococcygeal teratoma (Altman type IV), a neuroblastoma, a rhabdomyosarcoma, a clear cell sarcoma and an Ewing's sarcoma of the ilium. These tumors can be broadly categorized as tumors of germ cell, neuroblastic, mesenchymal and osteogenic origin. Despite overlapping imaging features, a review of the existing literature and careful retrospective observation revealed several distinctive features that aid in the optimal characterization of tumors. These include the tumor's epicenter, the pattern and degree of bone involvement, the status of sacral foramina and neural elements, and internal tumor characteristics such as the presence of fat, calcification, hemorrhage and necrosis.

Incidence of and Risk Factors for Screw Loosening after Iliosacral Screw Fixation for Posterior Pelvic Ring Injury.

Screw loosening is a common complication of iliosacral screw fixation, with subsequent loss of stability and fracture re-displacement. This study aimed to investigate the incidence of and risk factors for screw loosening after iliosacral screw fixation for posterior pelvic ring injury. A total of 135 patients with posterior pelvic ring injuries who were treated with iliosacral screw fixation in our department between July 2015 and April 2021 were selected for this retrospective analysis. The possible risk factors for screw loosening were investigated using univariate and multivariate logistic regression analyses of patient demographics and trauma-related and iatrogenic variables, including age, sex, body mass index, Osteoporosis Self-Assessment Tool for Asians (OSTA) index, mechanism of injury, Young-Burgess classification, site of injury, type of injury, type of screw, mode of fixation, numbers of guidewire adjustments, accuracy of screw position, and quality of fracture reduction. The incidence of screw loosening was 15.6% (n = 21). The mean duration for screw loosening was 3.2 ± 1.5 months after operation. Univariate analysis results showed that the Young-Burgess classification, type of injury, site of injury, type of screw, mode of fixation, and OSTA index might be related to screw loosening (p < 0.05). According to the multivariate logistic regression, vertical shear injuries (Odds ratios [OR] 9.80, 95% Confidence intervals [CI] [1.96-73.28], p = 0.008), type of injury (OR 0.25, 95% CI [0.13-0.79], p = 0.027), common screws (OR 6.94, 95% CI [1.53-31.40], p = 0.012), screws insertion only at the level of the first sacral segment (S1) (OR 8.79, 95% CI [1.18-65.46], p = 0.034), injury site located in the medial sacral foramina (OR 6.28, 95% CI [1.16-34.06], p = 0.033), and lower OSTA index [OR 0.41, 95% CI [0.24-0.71], p = 0.001] were significantly related to screw loosening. Vertical shear injuries, sacral fractures, injury site located in the medial sacral foramina, and lower OSTA index are significantly associated with the postoperative occurrence of screw loosening. Transiliac-transsacral screw fixation and screws insertion both at the level of the S1 and second sacral segment can prevent screw loosening.

Comparison of patterns and rates of cement leakage in percutaneous sacroplasty for sacral insufficiency fractures versus neoplasia.

Percutaneous sacroplasty is a minimally invasive procedure which utilises injection of bone cement into the sacrum for stabilisation of osteoporotic sacral insufficiency fractures (SIF) and neoplastic lesions to relieve pain and improve function. While effective, cement leakage is an important complication associated with the procedure. This study aims to compare the incidence and patterns of the cement leakages following sacroplasty for SIF versus neoplasia and discuss the various patterns of cement leakage and their implications. This retrospective study analysed 57 patients who underwent percutaneous sacroplasty at a tertiary orthopaedic hospital. Patients were divided into 2 groups of SIF (n=46) and neoplastic lesions (n=11) based on their indication for sacroplasty. Pre- and post-procedural CT fluoroscopy was used to assess for cement leakage. The incidence and patterns of cement leakage were both compared among the two groups. A Fisher's exact test was used for statistical analysis. Eleven (19%) patients had cement leakage on post-procedural imaging. The most common sites of cement leakage were into the presacral region (6), followed by sacroiliac joints (4), sacral foramina (3) and posterior sacral (1). There was a statistically significant higher incidence of leakage in the neoplastic group in comparison to SIF group (P-value <0.05). The incidence of cement leakage in the neoplastic group was 45% (n = 5/11) versus SIF 13% (n=6/46). There was a statistically significant higher incidence of cement leak in sacroplasties conducted for the treatment of neoplastic lesions compared to those with sacral insufficiency fracture.

Determination of Sexual Dimorphism of the Human Sacrum Based on Receiver Operating Characteristic Curve Analysis of Morphometric Parameters.

Background Sex estimation of unidentified incomplete skeletons poses a challenge to paleoanthropologists and forensic experts. The sacrum is a part of the axial skeleton and contributes to the formation of the pelvic girdle. It is a significant bone for the identification of the sex in the human skeletal system due to associated functional differences of the pelvic bones in males and females. However, there is a lack of cognizance of different morphometric parameters of the sacrum which may be crucial for determining sex, particularly when a part of the bone is available. This study aimed to recognize the best morphometric parameters for the identification of the sex of the sacrum even when fragmented bones were available and compare the various parameters for sexual dimorphism in different populations. Methodology The study was conducted on 110 dry adult human sacra in the anatomy department. Out of these, 42 sacra were female and 68 were male. Morphometric measurements were performed with the help of a digital vernier caliper. Statistical analysis was performed using SPSS version 17.0 (SPSS Inc., Chicago, IL, USA). Morphometric measurements of male and female sacra were compared using Student's t-test. The receiver operating characteristic (ROC) curve analysis was performed to establish the most appropriate cut-off values for each parameter. Results The mean sacral length measured from the promontory to the apex of the sacrum was higher in males compared to females (p < 0.001), whereas the sacral index was higher in female sacra in comparison to male sacra (p < 0.001). Furthermore, the mean height of the first posterior sacral foramina (PSF) was higher in male sacra bilaterally (p < 0.05). On ROC analysis, the area under the curve was 0.994 for the sacral index and 0.862 for the sacral length. Conclusions In this study, the sacral index was noted to be the most important morphometric parameter for the identification of the sex of the sacra. Additionally, the height of the S2 body, the height of the first anterior sacral foramina, and the height of the first PSF can be contemplated with an accuracy of 60-70% if only a part of the sacrum is available for determining the sex. Hence, this study emphasizes the significance of morphometric parameters of the sacrum in the determination of sex, especially in forensic cases when the skull and pelvis are fragmented or unavailable.

Anti-Inflammatory Effects of Two-Week Sacral Nerve Stimulation Therapy in Patients With Ulcerative Colitis

Background and AimsSacral nerve stimulation (SNS) showed anti-inflammatory properties in animal models of inflammatory bowel disease. We aimed to evaluate the effectiveness and safety of SNS in patients with ulcerative colitis (UC). Materials and MethodsTwenty-six patients with mild and moderate disease were randomized into two groups: SNS (delivered at S3 and S4 sacral foramina) and sham-SNS (delivered 8–10 mm away from sacral foramina), with the therapy applied once daily for one hour, for two weeks. We evaluated the Mayo score and several exploratory biomarkers, including C-reactive protein in the plasma, pro-inflammatory cytokines and norepinephrine in the serum, assessment of autonomic activity, and diversity and abundance of fecal microbiota species. ResultsAfter two weeks, 73% of the subjects in the SNS group achieved clinical response, compared with 27% in the sham-SNS group. Levels of C-reactive protein, pro-inflammatory cytokines in the serum, and autonomic activity were significantly improved toward a healthy profile in the SNS group but not in the sham-SNS group. Absolute abundance of fecal microbiota species and one of the metabolic pathways were changed in the SNS group but not in the sham-SNS group. Significant correlations were observed between pro-inflammatory cytokines and norepinephrine in the serum on the one side and fecal microbiota phyla on the other side. ConclusionsPatients with mild and moderate UC were responsive to a two-week SNS therapy. After performing further studies to evaluate its efficacy and safety, temporary SNS delivered through acupuncture needles may become a useful screening tool for identifying SNS therapy responders before considering long-term implantation of the implantable pulse generator and SNS leads for performing long-term SNS therapy.

V12-02 SACRAL NEUROMODULATOR OPTIMAL LEAD PLACEMENT TECHNIQUE

You have accessJournal of UrologyCME1 Apr 2023V12-02 SACRAL NEUROMODULATOR OPTIMAL LEAD PLACEMENT TECHNIQUE Sabrina Stair, Una Lee, and Alvaro Lucioni Sabrina StairSabrina Stair More articles by this author , Una LeeUna Lee More articles by this author , and Alvaro LucioniAlvaro Lucioni More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003347.02AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Sacral neuromodulation is an FDA approved treatment for overactive bladder. Efficacy depends on correct lead placement. The optimal lead placement technique uses real-time fluorosocpy to place the the sacral neurostimulator lead into the most superior and medial aspect of the S3 foramen. Here, we seek to provide guidance on using the optimal lead placement technique. METHODS: Using a recent sacral neurostimulator implant as an example case, we outline the critical steps and key teaching points for sacral neurostimulator implant. RESULTS: Optimal lead placement technique is demonstrated within the video. The patient is positioned in swimmer's position. Real time fluoroscopy is used to identify the most medial aspect of the sacral foramina, and then to guide the entry point of the introducer needle such that it is parallel to the bone seam. This lead placement maximizes stimulation of S3 sacral nerve roots while minimizing stimulation of S2 and S4 nerve roots. In an ideally placed lead, bellows response occurs before toe response. The lead is tested prior to full implant. CONCLUSIONS: Correct patient positioning and knowledge of target anatomy is key the optimal lead placement technique. Optimal lead placement technique uses real time imaging to place lead precisely, leading to improved clinical outcomes. This also increases the efficiency of lead placement, leading to faster operative times and increased cost-savings. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1065 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sabrina Stair More articles by this author Una Lee More articles by this author Alvaro Lucioni More articles by this author Expand All Advertisement PDF downloadLoading ...

Does minimally invasive percutaneous transilial internal fixator became an effective option for sacral fractures? A prospective study with novel implantation technique

AimTo assess radiological and functional outcomes of transilial internal fixator (TIFI) for treatment of sacral complete transforaminal fractures with a novel implantation technique that decrease wound irritation problems in addition to facilitating easy application of reduction methods beside showing the best entry points, screw trajectories and angles.MethodsA Prospective case series from 2019 to 2021 was conducted at university hospital including 72 patients with Denis type 2 sacral fractures. The operative and fluoroscopy time, reduction, implantation techniques, postoperative radiological and functional data were collected and evaluated with minimum follow-up of 12 months.ResultsThe mean initial fracture displacement was 4.42 mm while mean postoperative maximum residual fracture displacement was 2.8 mm, Radiological outcome assessed using Matta’s grading at the final follow-up visit with 63 cases scored as Excellent,7 cases as Good, 2 cases as fair. Functional outcome using Majeed scoring shows 64 cases of Excellent grading and 8 cases were Good. Short operative and fluoroscopy time, easy reduction techniques, few skin problems were recorded.ConclusionTIFI through a minimally invasive technique represents a valid method for dealing with transforaminal sacral fractures. TIFI provides a rigid fixation for posterior ring injuries with few risks regarding iatrogenic nerve injury, avoiding different variations of upper sacral osseous anatomy or sacral dysmorphism. In addition, there is no necessity for high quality fluoroscopy for visualization of sacral foramina intraoperatively, decreasing risk of radiation exposure, unlike other methods of fixation as iliosacral screws. Our novel modification for implantation technique provides few risks for postoperative and wound complications.

Morphometric Examination of the Sacroiliac Region and Variable Positions of the Sacral Auricular Surface: Anatomical Classification and Importance.

Anatomical variations of the sacrum involve alterations in the number of sacral segments, auricular surface area, and neural arch dimensions and are associated with biomechanical, surgical, and obstetric implications. Due to the complex functional structure of the sacroiliac (SI) joints, it was aimed to evaluate their morphometric structure, classify the sacrum, and group different locations of the auricular surface in the sacrums. Sex determination was made in 91 dry human sacra. Determination of the alpha angle on the sagittal axis of the auricular surface of the sacrum and classification of the auricular surface of the sacrum wasperformed.The sacra were studied to determine the position and extent of their auricular surfaces in relation to the sacral segments. Specimens were grouped as "normal," "high-up," and "low-down" auricular surface-bearing sacra. The sacral surface areas were measured, and SI joints were classified into three types morphologically (types I, II, and III). The depth and anterior-posterior length of the cranial, middle, and caudal impressions observed in the posterior sacrum and anterior-posterior lengths were measured. The measurements made for sex determination showed that 46 of the sacra were from females and 45 were from males.The alpha angle on the sagittal axis of the sacral auricular surface was found to be greatest at the level of the first posterior sacral foramina. While the most common sacrum type was Type III, the least common type was Type I. The surface area of facies auricularis was found to be larger in males than in females. With regard to facies auricularis in all sacrum groups, although it covered approximately 2.5 sacral vertebrae, there was a difference in the location of facies auricularis in the sacral vertebrae. A statistically significant difference was found between right and left in the depth values of the impressions in the dorsal surface of the sacrum (p <0.05). The position of the auricular surface in the sacrum differed among individuals. These differences are associated with variable load-bearing in the SI joints. The biomechanical classification of the sacrum and localization of the auricular surface can provide information about the anatomic source of low back pain or help predict the location of low back pain. Changes in the synovial surface morphology of the SI joints may elicit sacroiliac joint pain. This study was conducted because it is considered that the location of the auricular surface can significantly affect load-bearing patterns of the sacrum.

Sacral Multifidus Plane Block – A Way Forward to Provide Perioperative Analgesia for Spinopelvic Fixation Surgery

Sacral Multifidus Plane Block – A Way Forward to Provide Perioperative Analgesia for Spinopelvic Fixation Surgery

Morphological and morphometric studies on the axial skeleton of the sitatunga (Tragelaphus spekii gratus)

BackgroundAnatomical features of the skeleton of wild animals contribute largely to their adaptation. A dearth of information on the skeletal anatomy of the sitatunga (Tragelaphus spekii gratus) necessitated this study. Two adult sitatunga carcasses weighing 54 kg and 57 kg were obtained after post-mortem examination. Bone preparation was achieved through cold water maceration protocol.ResultThe tympanic bulla was elongated and massive, resulting in the rudimentary appearance of the styloid and muscular processes of the temporal bone. The lacrimal bone had a somewhat triangular presentation with the lacrimal foramen on the caudal border of the facial surface while its dorsal border formed the lateral margin of the frontal sinus. There was no observable lacrimal fossa on this facial surface of the lacrimal bone. The facial tubercle was absent. The vertebral column formula was C7 T13 L6 S4 C10-14, and the atlas dorsal median tubercle was smooth, devoid of ridges. The spinous process of the axis extended the entire arch length to hang little above the odontoid process. The thoracic spinous processes were oriented dorso-caudally from T1 to T11; spinous process of T12 was vertical, while that of T13 was oriented dorso-cranially. The length of the transverse process of L1 and L6 were the same, and smaller than the length of those of L2-L5. There was incomplete fusion of sacral spinous processes. Three dorsal and ventral sacral foramina were identified laterally on each side of the vertebrae. The ribs were 26 in number (13 pairs). The sternum was comprised of 5 sternabrae separated by intersternal cartilage. The average number of bones of the axial skeleton was 75. Morphometric in formation included the length of skull, mandible and ribs; body length of vertebrae and spinous process length and height of the vertebrae.ConclusionThis study recorded anatomical features and biometric information on axial skeletal bones of the Sitatunga (Tragelaphus spekii gratus) thereby providing baseline data for future biomedical, archaeological and comparative skeletal anatomical studies.

A Rare Case of Epithelioid Hemangioma Presenting as an Isolated Sacral Mass

Epithelioid hemangioma (EH) is an uncommon benign vascular tumor of mesenchymal origin. It mainly presents as expanding nodules around the ear, the forehead, and long bones. Only a handful of cases have been found in cervical, thoracic, lumbar, and sacral vertebrae as lytic lesions with pain and neurological impairment. We present the case of a 36-year-old female with an incidental finding of a sacral mass along with inguinal lymphadenopathy on imaging. Initially, there were no symptoms. The mass gradually progressed and later showed an extraosseous extension with involvement of sacral neural foramina and nerve roots causing severe low back pain and weakness of the left lower extremity. Differential diagnoses initially included secondary metastases and chordoma. However, the biopsy of the mass revealed findings consistent with an EH. To our knowledge, this is the first case of EH presenting as an isolated mass in the sacrum and the third case of EH involving the sacrum in continuation with other vertebrae.EH should be in our differential diagnoses when there is a sacral mass.