Lumbosacral Laminectomy Research Articles

Diabetic Ketoacidosis Masquerading as Ventricular Bigeminy in an Adult Patient Scheduled for Emergency Lumbosacral Laminectomy for Cauda Equina Syndrome

Diabetic Ketoacidosis Masquerading as Ventricular Bigeminy in an Adult Patient Scheduled for Emergency Lumbosacral Laminectomy for Cauda Equina Syndrome

Comparing clinical outcomes of dogs suffering from degenerative lumbosacral stenosis upon surgical or nonsurgical treatment

PICO question In dogs suffering from degenerative lumbosacral stenosis (DLSS), is surgical treatment more effective than nonsurgical therapy in reducing lumbosacral pain and neurological dysfunction in the long-term? Clinical bottom line Category of research Treatment. Number and type of study designs reviewed Two papers were critically reviewed. They were prospective and retrospective studies. Strength of evidence Weak. Outcomes reported Besides the two studies, there are no other studies currently available that directly compare long-term clinical outcome of patients that have undergone nonsurgical and surgical treatment respectively. In the study comparing clinical outcome of nonsurgical treatment by epidural steroid injection (ESI) and surgical treatment of degenerative lumbosacral stenosis, dogs were classified into clinical severity groups ranging from mild to moderate to severe. Mild cases demonstrated degenerative lumbosacral stenosis (DLSS) compatible clinical signs such as lumbosacral pain, reluctance to climb stairs / jump / raise up, lameness and muscle atrophy but no neurological deficits. Moderate cases presented DLSS compatible clinical signs in combination with neurological deficits such as reduced flexor withdrawal, proprioceptive deficits and nerve root signature. Severe cases demonstrated DLSS compatible clinical signs with more severe neurological deficits such as tail paresis and absent perineal reflex. Clinical outcomes were considered complete if clinical signs had resolved at follow-up consultations, partial if there was substantial but incomplete improvement in clinical signs and failed if the dog did not improve or deteriorated further. Improvements in patient condition were measured in terms of clinical outcome grading which is in relation to the initial clinical severity group assigned to each dog. Improvement after single dose of ESI was seen in 27/32 dogs, with 17/22 (after accounting for four dogs whose owners have refused further treatment, five dogs lost to follow-up after re-check as well as one dog whose owners have opted for repeated ESI instillations) relapsing within 6 months. All 17 of these dogs that suffered a relapse after single ESI subsequently underwent surgical treatment and demonstrated improvement in clinical signs, with a complete response seen in eight dogs and a partial response seen in nine dogs. In the study comparing clinical outcome of conservative treatment of exercise restriction with phenylbutazone administration and surgical treatment of degenerative lumbosacral stenosis, outcomes were classified as good in dogs that regained preoperative activity levels; acceptable in dogs with persistent abnormality or requiring continued medication though otherwise active, and poor in all other cases. Out of 16 dogs treated surgically, 11 were treated by dorsal lumbosacral laminectomy and excision of the dorsal portion of the lumbosacral disc, while the other five had additional unilateral facetectomy to decompress the seventh lumbar nerve. Out of the 11 dogs treated with dorsal lumbosacral laminectomy and excision of the dorsal portion of the lumbosacral disc, 6/11 (54.5%) of dogs were deemed to have a good outcome, while 3/11 (27.3%) of dogs were deemed to have an acceptable outcome. Out of the five dogs treated with dorsal lumbosacral laminectomy and excision of the dorsal portion of the lumbosacral disc with additional unilateral facetectomy, 3/5 (60%) of dogs were deemed to have an acceptable outcome. The outcome of conservative treatment was deemed good in 8/16 (50%) of dogs in the conservative treatment group. Conclusion There is evidence suggesting that both nonsurgical and surgical treatments can improve clinical outcomes and reduce lower back pain and neurological deficits. However, based on the current limited literature, it cannot be ascertained whether surgical treatments are more effective than nonsurgical treatments in improving long-term clinical outcomes and vice versa. In the study that tested the efficacy of epidural steroid injection, only a single dose of steroids was given in this study, making it a potential reason for the high rate of relapse following nonsurgical treatment. For surgical treatment of DLSS, the type of surgical procedure chosen would also depend on the part of the lumbosacral region which fails and leads to compression. In conclusion, randomised controlled trials that compare different forms of nonsurgical treatment with surgical treatment for dogs with DLSS caused by different underlying factors need to be conducted to properly address the PICO question. How to apply this evidence in practice The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources. Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.

200. Preventing surgical site hematoma with intravenous and topical tranexamic acid in lumbosacral surgery in a community teaching hospital: a resident-driven quality improvement project

<h3>BACKGROUND CONTEXT</h3> Postoperative hematoma following lumbosacral surgery carries significant morbidity. Tranexamic acid (TXA) has been shown to mitigate perioperative blood loss in lumbosacral fusion. <h3>PURPOSE</h3> We sought to report a quality improvement (QI) protocol using intravenous (iv) and/or tTXA to reduce postoperative surgical site hematoma (SSH) in patients undergoing elective lumbosacral surgery. <h3>STUDY DESIGN/SETTING</h3> Longitudinal comparative cohort. <h3>PATIENT SAMPLE</h3> Consecutive adults who underwent elective lumbosacral laminectomy and/or fusion in a single institution. <h3>OUTCOME MEASURES</h3> SSH hematoma necessitating evacuation of hematoma or readmission to the hospital due to hematoma. <h3>METHODS</h3> The FADE model was used. A feasibility study was performed in 2019 using IV or tTXA. Retrospective chart review demonstrated preimplementation baseline (7/1/18-6/30/19) SSH rate. Multiple interdisciplinary meetings were conducted to ensure standardized coagulopathy screening, TXA administration, drug supply, and compliance monitoring. Topical TXA was given in 2 g/250 NS via 60mL bulb syringe while ivTXA was given as 1 g bolus over 10 minutes. The QI project was integrated with the residents' patient safety activity. The QI start date was February 2020 with the interim analysis set for June 2020. The primary outcome was postoperative hematoma necessitating evacuation or hospital readmission. The secondary outcome was hospital length of stay. The post-implementation data were collected prospectively. A final analysis was performed for July 2020 - October 2020. Univariate analysis was used to compare outcome measures between pre- and postimplementation populations. A p-value < .05 was considered significant. A sample size calculation determined that there should be 198 patients in each group for a total of 396 patients. <h3>RESULTS</h3> During interim analyses, we found inadequate compliance with tTXA usage (68.5%). Stakeholders were reeducated regarding usage of tTXA and the implementation date was redefined as 7/1/2020. Comparing consecutive lumbosacral surgical patients in pre- (219 patients) and postimplementation (258 patients), the postimplementation group demonstrated significantly reduced incidence of SSH requiring evacuation (.38% vs 3.3%, p<.001) TXA compliance significantly improved after QI implementation (86.8% vs 9.6%, p=.001). The postimplementation tTXA group demonstrated that our standardized protocol resulted in a significantly lower incidence of SSH (.45% vs 4.8%, p=.004). <h3>CONCLUSIONS</h3> Our QI project demonstrated that the use of IV and tTXA was associated with a significantly lower rate of SSH requiring evacuation. We also demonstrated that the use of standardized administration of tTXA was associated with similar benefits when compared with nonstandardized tTXA administration. <h3>FDA DEVICE/DRUG STATUS</h3> tranexamic acid (Investigational/Not Approved)

Polypropylene mesh inhibits post-laminectomy compressive scar formation in rabbits: Histopathological and computational morphometric evaluation

We evaluated the effect of polypropylene mesh placement on post-laminectomy compressive scar formation in rabbits. Twenty-two white male New Zealand rabbits were distributed into two groups (n = 11). In the control group, the animals underwent lumbosacral laminectomy, whereas in the mesh group, the rabbits were submitted to lumbosacral laminectomy followed by the attachment of a polypropylene mesh to the vertebrae by the application of N-butyl cyanoacrylate. After eight weeks, the rabbits were euthanized, and the laminectomy area was collected for macro- and microscopic analyses. Macroscopically, we evaluated the (1) vertebral canal height; (2) laminectomy width and (3) length; and (4) fibrosis width, (5) height, and (6) length. Microscopically, we evaluated (7) fibroblasts; (8) the thickness of the dura-mater; and (9) the distance between the dura-mater and the laminectomy area. Macroscopically, there were no differences between the groups regarding vertebral canal height; width and length of the laminectomy; and fibrosis width. However, the height, and length of fibrosis were smaller in the mesh group. Microscopically, there were no differences in dura mater thickness and the distance between the dura mater and laminectomy area, but fewer fibroblasts were observed in the mesh group. This indicated that the polypropylene mesh improved tissue repair, with greater tissue organization. The results demonstrate that the use of a polypropylene mesh in the treatment of post-laminectomy wounds in rabbits reduces the severity of compressive fibrous scar formation. Polypropylene mesh is presented as a good alternative to reduce complications associated with laminectomy surgeries.

P113. Pedicle morphology of the lumbar spine in a diverse population

BACKGROUND CONTEXT Recent literature underscores the importance of understanding diverse pedicle isthmus morphology to perform successful transpedicular procedures. These studies suggest that more detailed and reliable measurements of pedicles should be undertaken. However, none of the current literature comprehensively compares average pedicle diameters (PDs), estimated pedicle screw lengths (EPSLs) or transverse pedicle angle (TPA) between diverse racial populations with a standardized study design. PURPOSE We sought to determine how height, weight and race correlated with PD, EPSL and TPA in the lumbar spine between various races: 'Asian', 'Black', 'White' and 'Hispanic/Other.' These data could aid in perioperative planning during instrumented spinal fusion. STUDY DESIGN/SETTING Retrospective chart review. PATIENT SAMPLE CT scans of the abdomen and pelvis performed over a 2-week period (between July 1, 2016 to July 14, 2016) at seven hospitals within a single health system was performed. Data was collected and categorized on the basis of patient-reported racial information, race was categorized as ‘Asian’, ‘Black’, ‘White’, and ‘Hispanic/Other.’ Patients were excluded if they had prior lumbo-sacral laminectomy or fusion, CT imaging that did not allow for visualization of all five lumbar segments, scoliosis involving the lumbar vertebrae with Cobb measurement angle greater than 20°, and patients with spondylolisthesis having greater than 25% slippage. OUTCOME MEASURES N/A METHODS Analysis of over 5,060 lumbar pedicles from randomly selected CT scans on patients who underwent imaging over a two-week period for non-back pain related complaints was conducted. Outer cortical PD (as measured through the isthmus), EPSL (measuring the posterior entry point at the longest distance, which perpendicularly transected the measured isthmic diameter to the anterior cortex) and TPA (midline bisecting vertebral body to the mid-axis of the pedicle bilaterally) were determined. Data was collected and categorized on the basis of patient reported race, height and weight. To determine the significance, we used a mixed analysis of variance and a post hoc analysis. RESULTS Height and weight significantly correlated with PD, whereas BMI did not. The Asian cohort consistently had significantly smaller PD at L1–L5 than Blacks or Whites (p CONCLUSIONS Pedicle anatomy is variable. There are significant differences among races, heights and weights. We suggest using preoperative CT for pedicle screw templating as a safe method for maximizing pullout strength given the variability of pedicles among a diverse population. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Validation of a methodology for neuro-urological and lumbosacral stimulation studies in domestic pigs: a humanlike animal model.

Spinal cord injuries (SCIs) result in loss of movement and sensory feedback, but also organ dysfunction. Nearly all patients with complete SCI lose bladder control and are prone to kidney failure if intermittent catheterization is not performed. Electrical stimulation of sacral spinal roots was initially considered to be a promising approach for restoring continence and micturition control, but many patients are discouraged by the need for surgical deafferentation as it could lead to a loss of sensory functions and reflexes. Nevertheless, recent research findings highlight the renewed interest in spinal cord stimulation (SCS). It is thought that synergic recruitment of spinal fibers could be achieved by stimulating the spinal neural networks involved in regulating physiological processes. Paradoxically, most of these recent studies focused on locomotor issues, while few addressed visceral dysfunction. This could at least partially be attributed to the lack of methodological tools. In this study, the authors aim to fill this gap by presenting a comprehensive method for investigating the potential of SCS to restore visceral functions in domestic pigs, a large-animal model considered to be a close approximation to humans. This methodology was tested in 7 female pigs (Landrace pig breed, 45-60 kg, 4 months old) during acute experiments. A combination of morphine and propofol was used for anesthesia when transurethral catheterization and lumbosacral laminectomy (L4-S4) were performed. At the end of the operation, spinal root stimulation (L6-S5) and urodynamic recordings were performed to compare the evoked responses with those observed intraoperatively in humans. Nervous excitability was preserved despite long-term anesthesia (mean 8.43 ± 1.5 hours). Transurethral catheterization and conventional laminectomy were possible while motor responses (gluteus muscle monitoring) were unaffected throughout the procedure. Consistent detrusor (approximately 25 cm H2O) and sphincter responses were obtained, whereas spinal root stimulation elicited detrusor and external urethral sphincter co-contractions similar to those observed intraoperatively in humans. Pigs represent an ideal model for SCS studies aimed at visceral function investigation and restoration because of the close similarities between female domestic pigs and humans, both in terms of anatomical structure and experimental techniques implemented. This article provides methodological keys for conducting experiments with equipment routinely used in clinical practice.

A Rare Case of Anterior Sacral Meningocele (ASM) in a Young Patient

We report a 24-year-old male who presented with abdominal distension, constipation and left sided groin pain. CT and MRI of the abdomen/spine were performed which showed a large anterior sacral meningocele occupying most of the pelvic and abdominal cavity and displacement of their respective contents. Initially a posterior approach with lumbosacral laminectomy (L5 - S4) was performed. The ostium of the meningocele was identified with several nerve roots identified passing through, adjacent and into the defect. As nerve roots traversed the ostium, watertight closure was not feasible without sacrificing nerve roots. Subsequent MRI demonstrated recurrence of approximately 60% of the anterior sacral meningocele. We therefore opted to approach the ASM anteriorly via an anterior approach with the help of colorectal surgical colleague. The ASM was completely embedded within the sigmoid and upper to mid rectal mesentry, with its own vascular supply to the thick walled capsule. This case highlights the need for a combined approach due to the incorporation of the pseudomeningocele into the omentum with the development of its own blood supply.

Clinical signs and outcome of dogs treated medically for degenerative lumbosacral stenosis: 98 cases (2004-2012).

To compare clinical signs of dogs treated medically or surgically for degenerative lumbosacral stenosis (DLSS) and assess outcome after medical treatment. Retrospective case series. Client-owned dogs treated medically (n = 49) or surgically (49) for DLSS. Medical records from 2004 to 2012 were reviewed. Dogs were included if they had clinical signs, clinical examination findings, and MRI abnormalities consistent with DLSS. Several variables were compared between surgically and medically treated dogs: age, sex, duration of clinical signs, presence or absence of neurologic deficits, urinary and fecal incontinence, concurrent medical conditions, and medical treatment before referral. Medical treatment after obtaining a final diagnosis of DLSS consisted of restricted exercise in combination with anti-inflammatory and analgesic drugs. Surgical treatment consisted of dorsal lumbosacral laminectomy. Outcome for medically treated dogs was obtained via a standardized questionnaire. Neurologic deficits were observed significantly more often in surgically treated dogs. Surgically treated dogs had unsuccessful medical treatment before referral significantly more often than did medically treated dogs. Thirty-one of 49 (63.3%) medically treated dogs were available for follow-up evaluation. Of these 31 dogs, 17 (55%) were managed successfully, 10 (32.3%) were managed unsuccessfully and underwent surgical treatment, 3 (9.7%) were euthanized because of progression of clinical signs, and 1 (3.2%) was alive but had an increase in severity of clinical signs after medical management. Clinical signs differed in dogs treated medically or surgically for DLSS. Medical treatment for dogs with DLSS was associated with a fair prognosis.

Acute tension pneumocephalus secondary to whole spine pneumorrhachis as an unusual presentation of a colon cancer complicated by a transsacral cerebrospinal fluid leak

A 52-year-old woman who was having chemotherapy for treatment of an adenocarcinoma of the colon, was admitted to the emergency department because of a moderate neurological impairment. Head CT scan showed bifrontal pneumocephalus without fractures or discontinuities of the skull base. A few hours later, following the patient’s neurologic deterioration, a new CT scan showed tension pneumocephalus with air diffusion throughout the posterior cranial fossa and cervical spine. Because of air bubbles into the cervical spine, an MRI of the entire spinal canal was done. This exam revealed a whole spine pneumorrhachis along with a transforaminal air passage through the first right sacral foramen and a pyogenic collection anterior to sacral bone. An abdomen CT scan showed a massive relapse of the colon cancer and confirmed a hypodense collection contiguous to the anterior sacral surface, causing erosion of the sacral bone and dural layer with air penetration into the spinal canal. Neurosurgical treatment by a lumbosacral laminectomy and duraplasty was followed by tumour removal and omental covering of the pelvis. Her neurological symptoms were resolved completely. One month later, the patient began adjuvant chemotherapy.

116 TARGETED MOLECULAR ASSESSMENT OF PUDENDAL NERVE NEUROREGENERATIVE RESPONSE - A MEANS OF ANALYZING INJURY, RECOVERY, AND REGENERATIVE THERAPIES

You have accessJournal of UrologyUrodynamics/Incontinence/Female Urology: Basic Research II1 Apr 2012116 TARGETED MOLECULAR ASSESSMENT OF PUDENDAL NERVE NEUROREGENERATIVE RESPONSE - A MEANS OF ANALYZING INJURY, RECOVERY, AND REGENERATIVE THERAPIES Bradley Gill, Danli Lin, Brian Balog, Charuspong Dissaranan, Hai-Hong Jiang, and Margot Damaser Bradley GillBradley Gill Cleveland, OH More articles by this author , Danli LinDanli Lin Cleveland, OH More articles by this author , Brian BalogBrian Balog Cleveland, OH More articles by this author , Charuspong DissarananCharuspong Dissaranan Cleveland, OH More articles by this author , Hai-Hong JiangHai-Hong Jiang Cleveland, OH More articles by this author , and Margot DamaserMargot Damaser Cleveland, OH More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.164AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES This project aimed to validate an improved method of quantifying mRNA upregulation in small, isolated tissue samples using laser capture microdissection (LMD) and quantitative real-time PCR (Q-PCR). Upregulation of βII-tubulin, a cytoskeletal protein, provides a measure of the neuroregenerative response to peripheral nerve injury. This was investigated in the context of childbirth-related pudendal nerve (PN) injury by studying the PN cell bodies in Onuf's nucleus and validating the new method through comparison to results obtained using radioisotopes and in situ hybridization. METHODS Virgin Sprague-Dawley rats (N=4, 225-250g) received unilateral PN crush injury. Intracardiac perfusion of heparinized saline and lumbo-sacral laminectomy were performed 7-days later, after which the spinal cord was frozen in situ with liquid nitrogen and the L3-S2 segment removed en bloc and stored inside a cryotube in liquid nitrogen. The PN cell bodies, located in Onuf's nucleus at approximately the L6 spinal cord level in female rats, were identified anatomically via serial 10μm cryostat sections. Samples were collected on LMD slides, stored at −80°C, and then stained with thionin and fixed with ethanol and xylene. Using LMD, a total of 5 Onuf's nuclei from the injured side were isolated from serial sections in each rat, collected in cell lysis solution, and then frozen on dry ice. This was repeated on the uninjured contralateral side. Samples then separately underwent RNA isolation and DNA digestion prior to reverse transcription and subsequent non-biasing PCR cDNA pre-amplification that targeted βII-tubulin (gene: TUBB2C). Samples underwent Q-PCR using ribosomal 18s RNA (gene: 18s) as an endogenous control and expression after injury relative to no injury was determined. RESULTS The LMD-PCR method showed βII-tubulin was expressed 2.36 ± 0.46 times higher in injured compared to uninjured PN cell bodies. Prior in situ hybridization methods (N=19) showed a 2.49 ± 0.38 fold greater expression after the same injury done bilaterally and compared to uninjured rats. CONCLUSIONS The LMD-PCR method reproduced previous in situ hybridization findings without radioactive reagents and in 8-9 hours rather than 4 weeks, as with in situ hybridization. This new technique may be useful in preclinical studies assessing the neuroregenerative response to therapeutic agents. It has clinical implications not only in childbirth injury but also prostatectomy-related nerve injury. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e47 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Bradley Gill Cleveland, OH More articles by this author Danli Lin Cleveland, OH More articles by this author Brian Balog Cleveland, OH More articles by this author Charuspong Dissaranan Cleveland, OH More articles by this author Hai-Hong Jiang Cleveland, OH More articles by this author Margot Damaser Cleveland, OH More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Unilateral vs bilateral sacral neuromodulation in pigs with formalin-induced detrusor hyperactivity

To investigate the efficacy of unilateral vs bilateral sacral neuromodulation (SNM) under standard experimental conditions by stimulating the dorsal sacral roots in pigs with formalin-induced detrusor hyperactivity. After lumbosacral laminectomy in eight alpha-chloralose-anaesthetized Göttinger mini-pigs, the dorsal roots of the nerve S3 were inserted into separate compartments of a size-modified Brindley electrode. Detrusor hyperactivity was induced by intravesical instillation of a 0.25% formalin solution. Stimulation of the separated dorsal roots was performed on the unilateral right, respectively, the unilateral left side, as well as bilaterally and with stimulation off-phases in a randomized pattern. A biphasic rectangular signal (impulse 200 micros, 20 Hz, 2.0 V) was used for SNM. The bladder pressure values were registered on a urodynamic unit and evaluated as contractions and amplitudes per minute. During unilateral stimulation, the mean (sem) number of contractions was reduced significantly from 4.73 (0.66) to 2.73 (0.62). The amplitude was also reduced significantly from 12.86 (1.23) to 8.32 (0.66). By contrast, bilateral stimulation lowered the mean (sem) number of overactive detrusor contractions to 1.08 (1.02) and the amplitude to 3.08 (2.42), which are highly significant reductions. In this porcine model, bilateral neurostimulation was a more effective method of SNM than unilateral stimulation. We assume that this is due to the additive effect of stimulating both sides, as well as the greater chance of stimulating the relevant dorsal roots of the sacral nerve fibres. By contrast, unilateral neuromodulation may be only partially effective by not being capable of influencing the entire bladder, or possibly by allowing new formation of neuronal pathophysiological pathways.

Ureteric Injury After Iumbosacral Discectomy: A Case Report and Review of the Literature

Herein, a case of ureteric injury was inflected during lumbo-sacral laminectomy is reported to be added to the previously published 15 cases. Ureteric injury is a rare complication that may be encountered during lumbar disc surgery. We traced 15 cases that were published in literatures allover the past years with different management techniques. To the best of our knowledge, we report the first case that was treated by ileal ureteric replacement. Special attention should be paid regarding ureteric injury during surgery. Despite rare incidence of such injury with laminectomy, there were some reportable complications. So, surgeons should be aware of prediction, early diagnosis, and possible management alternatives for such injuries to safe patients from unsuspected handicapping.

Spontaneous Hemorrhage of a Spinal Ependymoma: A Rare Cause of Acute Cauda Equina Syndrome

An interesting case of spontaneous bleeding from an ependymoma of the filum terminale is presented. To document a rare case of rapid neurologic deterioration as a consequence of spinal tumoral hemorrhage and to highlight important issues regarding tumor histologic subtype and the impact of anticoagulation that have emerged from an illuminating review of the literature. To our knowledge, there have been only 8 reported cases of hemorrhage from an ependymoma of the filum terminale or conus medullaris causing acute cauda equina syndrome. Bleeding is described in the pathology texts as being a consequence of the vascular architecture of the myxopapillary subtype and so postulated to be more common in this group. Anticoagulation is recognized to increase the frequency of tumoral bleeding, but no studies report its effect of severity of clinical presentation. We report the case of a 57-year-old woman who developed nontraumatic acute cauda equina syndrome, including sphincter compromise. She underwent a lumbosacral laminectomy for evacuation of a hematoma, at which stage a filum terminale ependymoma was excised. Histopathologic analysis demonstrated it to be of a nonmyxopapillary subtype. The patient demonstrated gradual improvement of the neurologic deficit. At 12-month follow-up, her saddle area sensory deficit has resolved, her right lower limb is much stronger allowing her to walk long distances, and she is successfully performing intermittent self-catheterization of her bladder. The possibility of an underlying tumor should always be borne in mind so that adequate preoperative planning can be undertaken. The presence of the myxopapillary subtype should not prevent a clinician from excluding other reasons for hemorrhage, and counseling when reinstituting anticoagulation must include warning against a worse prognosis from any future hemorrhage.

Pelvic floor structures and sacral innervation influence rectal compliance

Structural anatomy and the surrounding pelvic floor musculature influence the compliance of the rectum. Additionally, afferent inputs and spinal reflexes from sacral spinal roots SI-S3 modulate rectal compliance. The individual contribution of these mechanisms has not been clearly established. Aims. The current study sought to evaluate the influence of pelvic floor muscles and sacral innervation, both afferent and efferent, on rectal compliance in the cat. Methods. Following surgical preparation, animals were decerebrated and ventilated. After a lumbo-sacral laminectomy, the sacral roots were exposed. All measures were obtained after stabilization of respiration and arterial pressure. Pressure-volume curves were determined during slow ramp distention (0 to 50 mmHg) in animals with intact pelvic floor (n= 10) and following isolation of the rectum from the pelvic floor musculature (n= 10). To assess the influence of spinal outflow and afferent inputs, rectal compliance was measured in the isolated rectum following transection of the dorsal and ventral sacral roots sequentially from SI to S3 and from dorsal to ventral (n=4). Results. Isolation of the rectum from the pelvic floor musculature resulted in a significant interaction effect (F(9,189)=6.12, p<O.OOI) due to a rightward shift of the pressure-volume curve in the lower range of distention (0-25 mmHg) without affecting compliance at higher pressure. Bilateral section of dorsal root SI further shifted the pressure-volume curve to the right (F(l,3)= 13.69, p=O.03). Subsequent sections to ventral root S3 failed to significantly influence rectal compliance. Section of ventral root S3 resulted in an additional rightward shift (F(l,3)=41.35, p=0.008) of the compliance curve. Conclusion. The rightward shift of the compliance curve in the lower distention range after isolation of the rectum from its pelvic floor anchors may have resulted from an alteration in adaptive relaxation of the longitudinal muscle. Section of sacral spinal afferents in the dorsal root S I and efferent inputs from ventral root S3 further shifted the compliance curve to the right. These observations suggest that afferent inputs and spinal reflexes may exert inhibitory influences on the rectum during distention, thereby initiating adaptive responses to rectal filling (Supported by DFG).

Discharge patterns of intramural mechanoreceptive afferents during selective distension of the cat's rectum.

The afferent input from the rectum to the central nervous system (CNS) has yet to be thoroughly characterized. The characteristics of mechanoreceptive rectal afferents have been studied in unanaesthetized decerebrate cats. Following lumbo-sacral laminectomy, single-unit activity (occasionally multi-unit activity) was recorded from centrally cut filaments of the sacral dorsal roots (predominantly S2), while a balloon was inflated in the rectum. Starting from their background activities (mean 15.1 imp sec-1, SD 7.6 imp sec-1), afferent discharge rate increased with increasing balloon pressure (mean threshold 6.3 mmHg, SD 3.6 mmHg). The dependence of firing rate on intrarectal pressure began to flatten out at 25 mmHg (mean; SD 10 mmHg). For 22 out of 29 units (76%) complete saturation occurred at 35 mmHg (mean; SD 15 mmHg) with a maximum discharge rate of 31 imp sec-1 (mean; SD 12.6 imp sec-1). In a number of recording sessions, cyclical rectal contractions were observed. In these cases, changes in firing of the units were closely related to changes in intrarectal pressure. Pressure-related afferent activity could be enhanced by parasympathomimetic drugs which augmented rectal contractions. We conclude that sacral dorsal roots contain afferents from low-threshold mechanoreceptors located in the rectal wall, and that these afferents monitor the filling state and contraction level of the rectum.

Epidural Hematoma of the Cauda Equina in a Child with Hemophilia A

The presenting signs, treatment, and outcome of an epidural hematoma of the cauda equina in a child with severe hemophilia are reported for the first time. A 20-month-old boy with severe hemophilia A (factor VIII <0.01 U/ml) presented with a 12-day history of refusal to stand and constipation of 5-7 days duration. He had normal deep tendon reflexes with normal sensation and withdrawal to pinprick of his lower extremities bilaterally. He stood on his right leg, but had inversion of his left foot and refused to bear weight on his left leg. MRI revealed an epidural hematoma of the cauda equina and a distended bladder. Factor VIII replacement therapy and lumbosacral laminectomy with evacuation of the hematoma resulted in recovery of a normal gait, but bladder dysfunction persisted for 11 months. Clean intermittent catheterization (CIC) was required until bladder function returned. Complete neurologic recovery occurred 11 months after presentation This case demonstrates the following points: (a) an epidural hematoma of the cauda equina in a child with severe hemophilia can present with neurologic findings that are as subtle as those seen in normal children; (b) CIC can be performed safely over an extended period without factor VIII replacement; and (c) complete recovery is possible, despite prolonged bladder dysfunction and a 12-day interval between the onset of symptoms and treatment.

Effect of bilateral sacral decentralization on detrusor contractility and passive properties in dog

AbstractA series of five dogs underwent complete parasympathetic decentralization through a lumbosacral laminectomy. A full‐thickness biopsy was taken from the anterior wall of the bladder before and 12 weeks after surgery. Both mucosa and adventitia were dissected out and muscle layer was cut into several consecutive longitudinal strips. Each strip was mounted in a muscle chamber and frequencyresponse curves were obtained at different pulse duration. Activelpassive force‐length relationships were then obtained under condi tions of maximal electrical stimulation (100 V, 2 msec, 40 cps), by stretching the strips in successive increments until length of maximal active force development was reached. Curves were normalized per unit cross‐sectional area of muscle. The maximum active stress of the specimens was taken as a measure of bladder contractility, and the rate of exponential increase in passive stress with strain (ratio of deformed to undeformed length) as a measure of detrusor stiffness.Twelve weeks after detrusor decentralization the following changes were found: (1) The frequency that yielded maximum contraction was 10 cps at 2‐ and 5‐;msec pulse duration as compared to 40 cps in controls at every pulse duration. (2) The maximum active stress was 123.9 ± 13.8 vs 244.7 ± 24.7 gm/cm2 in controls (p&lt;.001). (3) The level of strain corresponding to the maximal active stress was significantly reduced. (4) The stiffness of the bladder wall was markedly increased; the rate of exponential increase was 4.47 ± 0.63 vs 2.19 ± 0.42 in controls (p&lt;.001). (5) Thickness of the bladder wall was significantly increased (7 ± 1 vs 4 ± 1 mm; p&lt;.001). (6) Histology sections of the specimens demonstrated collagen infiltration in all layers as well as smooth muscle hyperplasia.In summary, the effects of parasympathetic decentralization of the bladder wall are collagen infiltration, increased thickness, increased stiffness, and decreased contractility.