Superior gluteal artery steal syndrome

A sacral ulcer is described where ischaemia due to a vascular "steal" syndrome in the gluteal angiotome was the cause of persistent failure of flap reconstruction. Thrombotic obliteration of the abdominal aorta had resulted in the development of collaterals which, paradoxically, deprived the flaps based on standard angiotomes of their major source of blood supply, as they became the major source of perfusion for the legs. Healing of the ulcer was successfully achieved only after aorto-iliac reconstruction. Two other cases of ischaemic sacral ulceration, associated with aortic occlusion, are described.     

Neurovascular risks of sacral screws with bicortical purchase: an anatomical study

The aim of this cadaver study is to define the anatomic structures on anterior sacrum, which are under the risk of injury during bicortical screw application to the S1 and S2 pedicles. Thirty formaldehyde-preserved human male cadavers were studied. Posterior midline incision was performed, and soft tissues and muscles were dissected from the posterior part of the lumbosacral region. A 6 mm pedicle screw was inserted between the superior facet of S1 and the S1 foramen. The entry point of the S2 pedicle screw was located between S1 and S2 foramina. S1 and S2 screws were placed on both right and the left sides of all cadavers. Then, all cadavers were turned into supine position. All abdominal and pelvic organs were moved away and carefully observed for any injury. The tips of the sacral screws were marked and the relations with the anatomic structures were defined. The position of the sacral screws relative to the middle and lateral sacral arteries and veins, and the sacral sympathetic trunk were measured. There was no injury to the visceral organs. In four cases, S1 screw tip was in direct contact with middle sacral artery. In two cases, S1 screw tip was in direct contact with middle sacral vein. It was observed that the S1 screw tips were in close proximity to sacral sympathetic trunk on both right and the left sides. The tip of the S2 screw was in contact with middle sacral artery on the left side only in one case. It is found that the tip of the S2 screw was closely located with the middle sacral vein in two cases. The tip of the S2 pedicle screw was in contact with the sacral sympathetic trunk in eight cases on the right side and seven cases on the left side. Lateral sacral vein was also observed to be disturbed by the S1 and S2 screws. As a conclusion, anterior cortical penetration during sacral screw insertion carries a risk of neurovascular injury. The risk of sacral sympathetic trunk and minor vascular structures together with the major neurovascular structures and viscera should be kept in mind.     

MRI visualization of the female pelvis in the plane of the tension-free vaginal tape (TVT) procedure

We evaluated the distances and angles of the major blood vessels from various pelvic structures in the plane of the tension-free vaginal tape (TVT) procedure in 19 pelvic MR imagies. The major blood vessels were the iliofemoral vessels. The mean distance of the left iliofemoral vessels from the midline was 5.7±0.4 cm, and 5.7±0.3 cm for the right vessels. The mean distance of the left sacral tuberosities from the midline was 5.5±0.4 cm, and 5.6±0.3 cm for the right vessels. The angle between the midurethra and the left iliofemoral vessels was 50.6±4.4 cm, and 49.6±4.0 cm for the right. A significant correlation was found between the distance of the right and left iliofemoral vessels from the midline and the distance of right and left sacral tuberosities from the midline (P<0.01, P<0.007). We suggest that palpation of the sacral tuberosities might indicate the location of the iliofemoral blood vessels.Abbreviations - TVT Tension-free vaginal tape - - MRI Magnetic resonance imagingEditorial Comment: The authors evaluated the distances and angles of the major pelvic blood vessels in the plane of the tension-free vaginal tape (TVT) procedure in 19 pelvic MR images. A statistically significant correlation was found between the distance of the iliofemoral vessels from the midline and the distance of the sacral tuberosities from the midline. The authors suggest that palpation of the sacral tuberosities might alert the surgeon to those patients at greater risk for iliofemoral vessel injury during the TVT procedure.The main concern with this study is that the pelvic MR images were obtained in the supine position whereas the TVT is performed in the lithotomy position, which may change the relations of pelvic blood vessels with reference to the urethra. Further studies are needed to evaluate the clinical significance of this interesting observation in reducing vascular injuries during the TVT procedure.     

Anthropometric studies of the human sacrum relating to dorsal transsacral implant designs

The sacrum offers several possibilities for fixation that, when combined, appear to provide a secure foundation for a dorsally-placed, transsacrally-fixed implant. The dorsal sacral landmarks, particularly the first and second dorsal foramina, are readily identifiable and relate in a consistent manner both qualitatively and quantitatively to the major mass of sacral bone, which is located ventrally to the vital structures of the sacrum. The authors have utilized these findings in the design of a new implant for direct sacral fixation.     

Sacral fracture with pseudomeningocele and cerebrospinal fluid fistula: case report and review of the literature

A patient who sustained an isolated transverse sacral fracture is presented. A large ventral sacral pseudomeningocele with cerebrospinal fluid (CSF) fistula developed. Eighteen previous cases of traumatic pseudomeningocele have been documented. A review of those cases leads these authors to conclude that: transverse sacral fractures are rare and have not been reported in association with a pseudomeningocele formation; at the 4th sacral vertebra, this is the lowest reported pseudomeningocele; and CSF fistula with sacral fracture is distinctly uncommon, reported in only one previous case. The presenting symptoms, diagnostic evaluation, treatment, and prognosis are discussed.     

Decancellation Sacral Osteotomy in Iliosacral Tumor Resection: A Technique for Precise Sacral Margins

En bloc resection of iliosacral sarcomas is a surgical challenge. There are substantial risks of inadequate margins, local recurrence, and nerve root loss when pelvic sarcomas involve sacral root canals and foramina. The decancellation technique uses principles similar to transpedicle decancellation in spinal deformity correction to perform the sacral osteotomy in iliosacral tumor resection. The technique aims at improving sacral margins and minimizing loss of neural function. We performed a decancellation osteotomy in five patients with sarcomas requiring difficult oblique or sagittal sacral osteotomies and selective root sacrifice. Through laminectomy and without anterior exposure, a precise full-thickness osteotomy of the sacrum was performed without major technique-related morbidities or complications. This was followed by formal pelvic resection and reconstruction. Surgical margins were adequate in all patients and all tumor-free nerve roots were preserved.     

Sacral nerve stimulation for pain relief in interstitial cystitis

A 60-year-old woman was treated for severe interstitial cystitis pain using sacral nerve stimulation. Pain and accompanying bladder dysfunction were improved by temporary and permanent sacral nerve stimulation. Six months after implantation of a sacral neuromodulator the patient is pain free and significantly improved on bladder dysfunction. Interstitial cystitis may be an indication for functional electrostimulation.     

Sagittal plane configuration of the sacrum in spondylolisthesis

STUDY DESIGN: A radiographic study of the sagittal sacral deformity in spondylolisthesis. OBJECTIVES: To characterize and classify the pathoanatomy of sagittal sacral deformation in spondylolisthesis. SUMMARY OF BACKGROUND DATA: Spondylolisthesis has been extensively described and reviewed in the literature. Deformity of the entire sacrum in spondylolisthesis potentially could affect the natural history, treatment options, and outcome. The sagittal contour of the entire human sacrum has never been quantitatively studied in spondylolisthesis. METHODS: A literature search was performed and data was gathered retrospectively on patients with spondylolisthesis at the authors' institution. Cases of degenerative spondylolisthesis were excluded. Specifically those patients with L5-S1 spondylolisthesis were studied. The authors studied standing lateral radiographs and performed statistical analysis to understand morphologic relations. RESULTS: A broad range of global sacral kyphosis (37-188 degrees ) exists in spondylolisthesis. Increasing sacral kyphosis is significantly associated with increasing percent slip, sacral horizontal angle, Neuman's classification, lumbar lordosis, and lumbar index. A simple classification of the spectrum of sacral deformity in the sagittal plane is presented. CONCLUSION: The entire sacrum in spondylolisthesis can develop a significant kyphotic deformity in the sagittal plane, and this is associated with other abnormalities found in the lumbosacral spine. Sacral deformity is a significant factor in the assessment of the sagittal contour of the patient with L5-S1 spondylolisthesis.     

Sacral neuromodulation in patients with interstitial cystitis: a multicenter clinical trial

Female patients with interstitial cystitis (IC) unresponsive to standard oral and intravesical therapy were enrolled at three clinical sites for percutaneous sacral nerve root stimulation (PNS) in a prospective, observational pilot study. Evaluation was in the form of a 3-day voiding diary completed both prior to and following the commencement of sacral nerve root stimulation. Symptoms were also assessed by the O'Leary–Sant Interstitial Cystitis Symptom and Problem Indices (ICSI and ICPI). Baseline and test stimulation values for voiding diary parameters and O'Leary–Sant scores were compared to determine treatment efficacy. A total of 33 patients were enrolled. Statistically significant improvements were seen in frequency, pain, average voided volume and maximum voided volume. Significant improvements were also seen in ICSI and ICPI scores. Subacute PNS appears to be effective in reducing symptom severity and increasing voided volumes in patients with IC previously unresponsive to standard therapy. Abbreviations IC Interstitial cystitis - SNS Sacral nerve root stimulation - PNS Percutaneous sacral nerve root stimulation - ICSI Interstitial Cystitis Symptom Index - ICPI Interstitial Cystitis Problem IndexEditorial Comment: The authors demonstrate that temporary sacral nerve stimulation improves the symptoms of refractory interstitial cystitis. This is a well-designed, multi-institutional prospective study using both objective and validated subjective markers to measure outcomes. This paper, along with other previously published studies on sacral neuromodulation for IC, lends support for additional investigations into sacral neuromodulation for refractory IC. Interstitial cystitis can be a difficult disease to treat and patients who are refractory to standard IC therapies either continue to suffer from their symptoms or have only major, irreversible, surgery as their sole option. Reconstructive surgery for IC often leads to poor clinical outcomes. Well-designed studies with long-term follow-up and careful reporting of outcomes of permanent implantation of a pulse generator are needed in IC. If sacral nerve stimulation is shown to improve the symptoms of IC, this will provide a reversible modality to enhance the quality of life of those suffering from this difficult disease.     

Lumbosacral osteomyelitis after robot-assisted total laparoscopic hysterectomy and sacral colpopexy

We report on the transabdominal resection of infected lumbosacral bone, synthetic mesh, and sinus tract following sacral colpopexy. A 45-year-old nulliparous patient who had undergone transvaginal mesh followed by robot-assisted sacral colpopexy presented with increasing back pain and foul-smelling vaginal drainage. An epidural abscess required surgical intervention, including diskectomy, sacral debridement, and mesh removal to drain the abscess and vaginal sinus tract. Recognized complications of open prolapse procedures also manifest following minimally invasive approaches. Osteomyelitis of the sacral promontory following sacral colpopexy may require gynecologic and neurosurgical management.     

Selective sacral nerve blockade for the treatment of unstable bladders

38 patients with severe urge or urge incontinence, who did not respond to conservative therapy, were treated with selective sacral nerve blockade using a local anesthetic (bupivacaine). 6 patients of this group had definite selective sacral denervation with phenol. In 31 patients a urodynamic study was done previous to the sacral nerve block as well as 10 and 90 min after the injection. Within the first 2-7 weeks the success rate was about 70% in regard to bladder capacity and mean volume at first desire to void. On long-term follow-up (greater than 7 months), the success rate decreased to about 16%. Only 1 patient of the phenol group still has complete detrusor areflexia for now more than 2 years. 4 male patients with advanced or locally recurrent bladder tumors had the sacral block because of severe perineal or suprapubic pain. Subjectively their response seemed to be better. According to our experience nonoperative central bladder denervation with selective sacral nerve blockade using local anesthetics or phenol shows no convincing results on long-term follow-up. Since it is a minimal invasive technique, which can be repeated several times, it may be helpful for some patients and offers a chance to bypass major surgical denervation procedures.     

第三、四骶骨螺钉应用的解剖学研究

目的通过对第三、四骶骨螺钉应用的解剖学测量,探讨第三、四骶骨螺钉应用的安全性。方法 32具成人骶骨标本。设定A点、B点和C点为螺钉进钉点,分别位于相邻骶后孔内侧缘连线的中点,相邻骶后孔连线的中点,经相邻骶后孔连线中点的水平线与骶外侧嵴的交点。D1、D2、D3、α和β、分别为水平面上骶骨内侧置钉,垂直置钉和外侧置钉的钉道长度,内侧置钉和外侧置钉最大偏移角度。d1、d3、θ和φ分别为矢状面上骶骨头侧置钉和尾侧侧置钉钉道长度,头侧置钉和尾侧置钉最大偏移角度。结果 S3螺钉在A和B点进钉,水平面上偏向外侧小于45.21°±10.66°,矢状面上偏向头侧小于8.50°±3.53°;C点进钉,水平面上偏向内侧小于52.00°±7.55°,矢状面上偏向头侧小于19.05°±6.36°。S4螺钉在A和B点进钉,水平面上偏向外侧小于49.50°±9.53°,矢状面上偏向头侧小于12.00°±4.24°,偏向尾侧小于14.00°±2.83°;C点进钉,水平面上偏向内侧小于66.19°±8.14°,矢状面上偏向头侧小于13.50°±3.54°,偏向尾侧小于28.50°±2.12°。结论了解第三、四骶骨的解剖结构和精确的螺钉放置可以保证骶骨螺钉固定成功。     

Second-line-Therapie der idiopathisch überaktiven Blase

The syndrome of idiopathic overactive bladder (I-OAB) impairs quality of life for the affected individuals. Conservative treatment options such as antimuscarinics are not always effective, and resulting side effects can lead the patient to stop treatment. In recently years, minimally invasive and reversible sacral neuromodulation and botulinum toxin A have become available. Currently, the approved treatment option for I-OAB that is recommended by the International Consultation on Incontinence is sacral neuromodulation by InterStim therapy. This article gives an overview of the present clinical evidence on the effectiveness and reliability of these two treatment modalities as well as the current significance of sacral neuromodulation and botulinum toxin A for the second-line treatment of adult I-OAB.     

Sacral kyphoplasty for relieving pain caused by sacral hemangioma

STUDY DESIGN: Case report describing sacral kyphoplasty in a patient with sacral hemangioma; the first account of this procedure in a sacral hemangioma. OBJECTIVES: To highlight the advantages of sacral kyphoplasty in the treatment of sacral tumors. SETTING: This study is made in Baskent University in Turkey. SUMMARY OF BACKGROUND DATA: Kyphoplasty and sacroplasty are new, minimally invasive techniques that are mostly used for treating osteoporotic vertebral body fractures. These techniques are very effective for achieving rapid pain relief and stabilizing the vertebra, and biopsy collection can be included in the procedure. The latter allows for informed treatment planning in patients with metastatic tumors. METHOD: A 74-year-old woman with known metastatic renal cell carcinoma was investigated for pain in the left sacral region. A tumoral lesion was detected, and sacroplasty was performed at S1. RESULTS: The sacral pain resolved completely after the procedure, and the patient was able to walk without assistance. The pathological diagnosis for the vertebral lesion was hemangioma. CONCLUSIONS: Sacral kyphoplasty is a very effective, minimally invasive surgical procedure. Patients with debilitating diseases such as primary sacral tumors or metastases can be treated by this technique with no significant complications.     

Reduction of lumbar scoliosis by use of a heel lift to level the sacral base

The relationship between unlevelness of the sacral base and scoliosis is unclear. A method for reducing mild lateral bend of the lumbar spine by use of a heel lift to level the sacral base was tested in adults. Special methods were used to demonstrate the weight-bearing plane of the sacral base and the angle of lateral bend radiographically. The procedure significantly decreased the unlevelness of the sacral base and significantly reduced the angle of lateral bend. The results suggest that an unlevel sacral base contributes to lumbar scoliosis and that use of a heel lift to level the sacral base in mild cases of lumbar scoliosis can be beneficial.     

Urethral function after chronic cauda equina lesions in cats. I. The contribution of mechanical factors and sympathetic innervation to proximal sphincter dysfunction

We investigated the contribution of mechanical and sympathetic neural factors to proximal urethral sphincter dysfunction in the cat after chronic sacral rhizotomy. Concomitant vesicostomy prevented a decrease in the urethral pressure profile measured three months post-rhizotomy. Sympathetic influences on basal urethral perfusion pressure were the same in neurally-intact and chronic rhizotomised cats. A significant prazosin-sensitive component of basal urethral perfusion pressure remained after section of all extrinsic urethral innervation in both neurally-intact and chronic cats. Local intra-arterial 6-hydroxydopamine also abolished this component. After rhizotomy, noradrenaline content in the proximal urethra was significantly increased but there was no change in sensitivity to sympathetic stimulation. A small (5% of control) atropine-sensitive and prazosin-resistant constriction was seen only after chronic sacral rhizotomy. We conclude that a mechanical factor associated with bladder expression and not an alteration in sympathetic control is the major factor leading to diminished proximal urethral closure after vesicourethral lower motor neuron lesion. Furthermore, short adrenergic neurons have an important role in the maintenance of urethral pressure in the normal state and after lower motor neuron lesion.     

The lumbar and sacral plexuses

The lumbar plexus is derived from the anterior primary rami of L1, L2, L3, and part of L4. It may also receive a contribution from T12. Its major derivatives are the femoral and the obturator nerves. The sacral plexus arises from the anterior primary rami of the five sacral nerves and the coccygeal nerve, together with the lumbosacral trunk, an important contribution which comprises the whole of L5 together with a contribution from L4. Its terminal branches are the sciatic and the pudendal nerve. In addition, both plexuses have numerous collateral muscular and cutaneous branches, and the sacral plexus gives rise to the pelvic parasympathetic outflow from S2 and S3.     

Percutaneous stabilization of U-shaped sacral fractures using iliosacral screws: technique and early results

PURPOSE: To present the technique and early results of percutaneous stabilization of U-shaped sacral fractures with attention to neurologic recovery and maintenance of fracture reduction of the sacrum. DESIGN: Retrospective clinical study. SETTING: Level I trauma center. PATIENTS: During a thirty-eight-month period, 442 patients with pelvic ring disruptions were treated at a Level I trauma center. Thirteen (2.9 percent) of these patients had displaced U-shaped sacral fractures treated with percutaneous stabilization. INTERVENTION: Fracture stabilization was accomplished using fluoroscopically guided iliosacral screws inserted percutaneously with the patient positioned supine. Neurodiagnostic monitoring was not used during screw insertions. This technique was limited to patients with sacral kyphotic deformities, which allowed in situ fixation. Sacral neurologic decompression was not performed. MAIN OUTCOME MEASUREMENTS: Fracture healing and the stability of fixation were assessed on inlet and outlet radiographs and a lateral sacral view. Detailed neurologic examinations were performed at injury and at follow-up. RESULTS: The sacral fractures were classified based on plain pelvic radiographs and computed tomography scans and included one Type 1, eight Type 2, and four Type 3 fracture patterns. Twenty-five fully threaded cancellous 7.0-millimeter cannulated screws were used. Eleven patients had bilateral screw fixations; one patient had unilateral double screw fixation; and one patient had unilateral single screw fixation. Operative time for screw insertion averaged forty-eight minutes, with 2.1 minutes of fluoroscopy per screw. Accurate screw insertions without neuroforaminal or sacral spinal canal violations were confirmed in all patients with postoperative pelvic plain radiographs and computed tomography scans. A paradoxical inlet view of the upper sacral segments on the injury anteroposterior pelvis was seen in twelve of thirteen patients (92.3 percent), and the diagnosis was confirmed with the lateral sacral view in all thirteen (100 percent) patients. Preoperatively, sacral kyphosis averaged 29 degrees, whereas postoperative sacral kyphosis averaged 28 degrees. Screw disengagement occurred without a change in position of the sacral fracture in the only patient treated with a single unilateral screw. All fractures healed clinically and radiographically. Of the nine patients with preoperative neurologic abnormalities, two (22 percent) patients had residual neurologic deficits. Both patients had associated multiple level lumbar burst fractures, which required decompression and instrumented stabilization. CONCLUSIONS: These sacral fractures are rare and occur after significant spinal axial loading. A paradoxic inlet view of the upper sacrum on the anteroposterior plain pelvic radiograph heralds the diagnosis. Delayed diagnosis is avoided by a high clinical suspicion, early lateral sacral radiographs, and pelvic computed tomography scans. Surgical stabilization may assist in early mobilization of the patient from recumbency and prevents progressive deformity with associated nerve root injury. Percutaneous fixation diminishes potential blood loss and operative times, yet still allows subsequent sacral decompression of the local neural elements using open techniques when necessary. Early percutaneous iliosacral screw fixation is effective treatment for these injuries.     

骶岬周围血管的应用解剖学研究

目的明确骶岬周围血管(bloodvesselsofperisacralpromontory,BVPSP)的解剖学特点,为与其相关的手术提供应用解剖学资料。方法成人尸体37具,观测BVPSP的组成,骶中血管的来源、走行、直径以及骶岬距骶1横干静脉的距离。结果BVPSP由左右髂总动静脉和髂内动静脉,骶中动静脉上段和骶1横干静脉组成;骶中动脉均来自腹主动脉;骶中静脉变异较大,管壁薄、缺乏瓣膜;在骶岬水平,骶中动、静脉的直径平均是1.02mm和2.53mm;骶中血管少在左侧近骶岬段经过。骶岬平面距骶1横干静脉的平均距离为5.75mm。结论BVPSP组成复杂,特别是骶中静脉变异多,骶1横干静脉距骶岬平面较近、与周围血管吻合丰富是造成与骶岬相关手术出血的解剖学基础。     

三种骶骨螺钉的生物力学研究

目的 研究三种骶骨螺钉植入法的生物力学性能。方法 对经椎弓椎间体内固定（PTSF）法、前内骶岬法、前外骶翼法三种骶骨固定法进行二个方面的研究：①摆动试验②轴向拨出试验。以助于对上述三种骨螺钉植入法的力学行为有较深入的了解。结果 轴向拨出试验结果：PTSF法抗拔出力最大,平均最大抗拔出力可达930N,明显大于前内骶岬方向螺钉的586N和前外骶螺钉的414N。在相同摆角下,PTSF法较其余二种方法所需力矩大,也就是说若要螺钉松动所作的功也就越大,前内骶岬螺钉固定较前外骶翼螺钉固定坚强。结论 PTSF法骶骨螺钉的抗拨出力和摆动力矩最大,固定最坚强,前骨骶岬方向骶骨螺钉次之,前外骶翼方向骶骨螺钉固定最差。