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Background: The objective of the research was to study the relevance of intraoperative neuromonitoring throughout all stages of surgical management in patients with progressive early-onset scoliosis (EOS).The routine monitoring of spinal cord potentials has gradually become standard of practice among spinal surgeons. However, there is not a consensus that the added expense of this technique necessitates monitoring in all stages of surgical management., Methods: A retrospective review of 180 surgical cases of 30 patients with EOS from July 2003 to July 2012 was performed. All monitoring alerts as judged by the neuromonitoring team were identified. Both somatosensory-evoked potentials and transcranial electric motor-evoked potentials were studied and no limiting thresholds for reporting electrophysiological changes were deemed appropriate., Results: Of 150 monitored cases there were 18 (12%) monitoring alerts. This represented 40% of the patient cohort over the 9-year study period., Conclusions: Index versus routine lengthening rate of alerts showed no significant difference in incidence of monitoring alerts. Conversely, several patients whose primary implantation surgeries were uneventful had monitoring alerts later in their treatment course. Intraoperative neuromonitoring is warranted throughout all stages of surgical management of EOS., Level of Evidence: Level IV. This study is a retrospective review of surgical cases of 30 patients with EOS.

Background: The painful dislocated hip in the setting of cerebral palsy is a challenging problem. Many surgical procedures have been reported to treat this condition with varying success rates. The purpose of this study is to retrospectively evaluate and compare the outcomes of 3 different surgical procedures performed at our institution for pain relief in patients with spastic quadriplegic cerebral palsy and painful dislocated hips., Methods: A retrospective chart review of the surgical procedures performed by 5 surgeons for spastic, painful dislocated hips from 1997 to 2010 was performed. The procedures identified were (1) proximal femoral resection arthroplasty (PFRA); (2) subtrochanteric valgus osteotomy (SVO) with femoral head resection; and (3) proximal femur prosthetic interposition arthroplasty (PFIA) using a humeral prosthesis. Outcomes based on pain and range of motion were determined to be excellent, good, fair, or poor by predetermined criteria., Results: Forty-four index surgeries and 14 revision surgeries in 33 patients with an average follow-up of 49 months met the inclusion criteria. Of the index surgeries, 12 hips were treated with a PFRA, 21 with a SVO, and 11 with a PFIA. An excellent or good result was noted in 67% of PFRAs, 67% of SVOs, and 73% of PFIAs. No statistical significance between these procedures was achieved. The 14 revisions were performed because of a poor result from previous surgery, demonstrating a 24% reoperation rate overall. No patients classified as having a fair result underwent revision surgery. All patients receiving revision surgery were eventually classified as having an excellent or good result., Conclusions: Surgical treatment for the painful, dislocated hip in the setting of spastic quadriplegic cerebral palsy remains unsettled. There continue to be a large percentage of failures despite the variety of surgical techniques designed to treat this problem. These failures can be managed, however, and eventually resulted in a good outcome. We demonstrated a trend toward better outcomes with a PFIA, but further study should be conducted to prove statistical significance., Level of Evidence: III.

Study Design: A retrospective analysis of the morbidity and mortality data collected by the SRS in 2009 with comparison to previous years., Objectives: Objective of this study was to assess the new format of morbidity and mortality data collection by the SRS in 2009 and evaluate the data collected with comparison to previous years., Summary of Background Data: 2009 morbidity and mortality reporting format was dramatically changed from previous years. This was done in an attempt to simplify the reporting process and to narrow the reporting to only three sentinel events: death, blindness, and neurologic injury. Only deformity cases including scoliosis, kyphosis, and Grade III or greater spondylolisthesis were included., Methods: Results were obtained from the SRS M & M reporting summary for 2009. These included detailed analysis for complications including death, blindness, and neurologic injury. These were compared to similar statistics obtained from the years dating back to 2001. Blindness has not previously been reported., Results: 80.1% of SRS members submitted 35,267 deformity cases. Both the percentage of members submitting data and the number of deformity cases far exceeded any previous year total. 57.6% of cases involved scoliosis, 10.5% kyphosis, and 31.9% spondylolisthesis. Neurologic complications were lower in each major category (scoliosis, kyphosis, and spondylolisthesis) compared to previous years. The death rate was similar to prior reporting 0.12%. Three cases of blindness were reported, two occurred in AIS. All three resolved., Conclusions: The altered format and requirement for all members to participate has dramatically increased the total number of deformity cases reported and percent of membership responding. Neurologic injury rates are decreased from previous years. Three cases of blindness occurred, all of which resolved. Further collection of data is needed to elucidate mechanism and prevention., (Copyright © 2013 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.)

Study Design: Retrospective chart review., Objective: To accurately determine complication rates, particularly mortality rates, in surgically treated early-onset scoliosis., Summary of Background Data: The advent of modern segmental instrumentation for spinal fusion surgery in adolescent scoliosis has allowed for application of similar nonsegmental unfused techniques aimed at controlling scoliosis in the very young child. The dismal prognosis for these children without repeated spinal lengthening procedures is unquestioned, although no controlled trials exist. Many, if not most, of these children need surgery; however, the surgical complication rate is very high., Methods: During the study period, all surgically treated children with early-onset scoliosis seen at our institution were identified. Any patient who presented to our clinic with early-onset scoliosis that was surgically managed was included. The total number of procedures, type of implants, number and type of complications, geographic origin of the cases, and final outcomes were all assessed., Results: A total of 165 surgical procedures on 28 patients accrued during the study time period, including index implantation of instrumentation, lengthening, and definitive fusion, as well as operations performed for complications such as wound debridement and revision of failed implants. Clinical diagnoses included congenital scoliosis, syndromic and chromosomal abnormalities, cerebral palsy, and spinal muscular atrophy. There was a complication rate of 84% overall with a mortality rate of almost 18%. The only patients with no complications were those whose entire surgical course had been at our institution only. The mortality rate was equal in patients whose treatment was performed elsewhere versus exclusively in our center., Conclusion: This study underlines the grave severity of these scolioses particularly in syndromic children. The high mortality rate is alarming, suggesting that further study is needed in this area.

Object: Patients with varied medical comorbidities often present with spinal pathology for which operative intervention is potentially indicated, but few studies have examined risk stratification in determining morbidity and mortality rates associated with the operative treatment of spinal disorders. This study provides an analysis of morbidity and mortality data associated with 22,857 cases reported in the multicenter, multisurgeon Scoliosis Research Society Morbidity and Mortality database stratified by American Society of Anesthesiologists (ASA) physical status classification, a commonly used system to describe preoperative physical status and to predict operative morbidity., Methods: The Scoliosis Research Society Morbidity and Mortality database was queried for the year 2007, the year in which ASA data were collected. Inclusion criterion was a reported ASA grade. Cases were categorized by operation type and disease process. Details on the surgical approach and type of instrumentation were recorded. Major perioperative complications and deaths were evaluated. Two large subgroups--patients with adult degenerative lumbar disease and patients with major deformity--were also analyzed separately. Statistical analyses were performed with the chi-square test., Results: The population studied comprised 22,857 patients. Spinal disease included degenerative disease (9409 cases), scoliosis (6782 cases), spondylolisthesis (2144 cases), trauma (1314 cases), kyphosis (831 cases), and other (2377 cases). The overall complication rate was 8.4%. Complication rates for ASA Grades 1 through 5 were 5.4%, 9.0%, 14.4%, 20.3%, and 50.0%, respectively (p = 0.001). In patients undergoing surgery for degenerative lumbar diseases and major adult deformity, similarly increasing rates of morbidity were found in higher-grade patients. The mortality rate was also higher in higher-grade patients. The incidence of major complications, including wound infections, hematomas, respiratory problems, and thromboembolic events, was also greater in patients with higher ASA grades., Conclusions: Patients with higher ASA grades undergoing spinal surgery had significantly higher rates of morbidity than those with lower ASA grades. Given the common application of the ASA system to surgical patients, this grade may prove helpful for surgical decision making and preoperative counseling with regard to risks of morbidity and mortality.

Object: Currently, few studies regarding morbidity and mortality associated with operative treatment of spinal disorders in children are available to guide the surgeon. This study provides more detailed morbidity and mortality data with an analysis of 23,918 pediatric cases reported in the multicenter, multisurgeon Scoliosis Research Society morbidity and mortality database., Methods: The Scoliosis Research Society morbidity and mortality database was queried for the years from 2004 to 2007. The inclusion criterion was age 18 years or younger. Cases were categorized by operation type and diagnosis. Details on the surgical approach, use of neurophysiological monitoring, and type of instrumentation were recorded. Major perioperative complications and deaths were evaluated. Statistical analysis was performed with chi-square testing, with a p value < 0.05 considered significant., Results: A total of 23,918 patients were included. The mean age was 13 ± 3.6 years (± SD). Spinal pathology included the following: scoliosis (in 19,642 patients), kyphosis (in 1455), spondylolisthesis (in 748), trauma (in 478), and other (in 1595 patients). The overall complication rate was 8.5%. Major complications included wound infections (2.7%), new neurological deficits (1.4%), implant-related complications (1.6%), and hematomas (0.4%). The most common medical complications were respiratory related (0.9%). Morbidity rates differed based on pathology, with patients undergoing treatment for kyphosis and spondylolisthesis having higher overall rates of morbidity (14.7% and 9.6%, respectively). Patients undergoing revision procedures (2034) or corrective osteotomies (2787) were more likely to suffer a complication or new neurological deficit. The majority of these deficits improved at least partially. Thirty-one deaths were reported for an overall rate of 1.3 per 1000. Respiratory complications were the most common cause of mortality (13 cases). Twenty-six of the deaths occurred in children undergoing scoliosis correction., Conclusions: Spinal surgery in children is associated with a range of complications depending on the type of operation. Mortality rates for all indications and operations were low. Patients undergoing more aggressive corrective procedures for deformity are more likely to suffer complications and new neurological deficits.

Background: Unintended durotomy is a common complication of spinal surgery. However, the incidences reported in the literature vary widely and are based primarily on relatively small case numbers from a single surgeon or institution., Objective: To provide spine surgeons with a reliable incidence of unintended durotomy in spinal surgery and to assess various factors that may influence the risk of durotomy., Methods: We assessed 108,478 surgical cases prospectively submitted by members of the Scoliosis Research Society to a deidentified database from 2004 to 2007., Results: Unintended durotomy occurred in 1.6% (1745 of 108 478) of all cases. The incidence of unintended durotomy ranged from 1.1% to 1.9% on the basis of preoperative diagnosis, with the highest incidence among patients treated for kyphosis (1.9%) or spondylolisthesis (1.9%) and the lowest incidence among patients treated for scoliosis (1.1%). The most common indication for spine surgery was degenerative spinal disorder, and among these patients, there was a lower incidence of durotomy for cervical (1.0%) vs thoracic (2.2%; P = .01) or lumbar (2.1%, P < .001) cases. Scoliosis procedures were further characterized by etiology, with the highest incidence of durotomy in the degenerative subgroup (2.2% vs 1.1%; P < .001). Durotomy was more common in revision compared with primary surgery (2.2% vs 1.5%; P < .001) and was significantly more common among elderly (> 80 years of age) patients (2.2% vs 1.6%; P = .006). There was a significant association between unintended durotomy and development of a new neurological deficit (P < .001)., Conclusion: Unintended durotomy occurred in at least 1.6% of spinal surgeries, even among experienced surgeons. Our data provide general benchmarks of durotomy rates and serve as a basis for ongoing efforts to improve safety of care.

Object: This is a retrospective review of 10,242 adults with degenerative spondylolisthesis (DS) and isthmic spondylolisthesis (IS) from the morbidity and mortality (M&M) index of the Scoliosis Research Society (SRS). This database was reviewed to assess complication incidence, and to identify factors that were associated with increased complication rates., Methods: The SRS M&M database was queried to identify cases of DS and IS treated between 2004 and 2007. Complications were identified and analyzed based on age, surgical approach, spondylolisthesis type/grade, and history of previous surgery. Age was stratified into 2 categories: > 65 years and ≤ 65 years. Surgical approach was stratified into the following categories: decompression without fusion, anterior, anterior/posterior, posterior without instrumentation, posterior with instrumentation, and interbody fusion. Spondylolisthesis grades were divided into low-grade (Meyerding I and II) versus high-grade (Meyerding III, IV, and V) groups. Both univariate and multivariate analyses were performed., Results: In the 10,242 cases of DS and IS reported, there were 945 complications (9.2%) in 813 patients (7.9%). The most common complications were dural tears, wound infections, implant complications, and neurological complications (range 0.7%-2.1%). The mortality rate was 0.1%. Diagnosis of DS had a significantly higher complication rate (8.5%) when compared with IS (6.6%; p = 0.002). High-grade spondylolisthesis correlated strongly with a higher complication rate (22.9% vs 8.3%, p < 0.0001). Age > 65 years was associated with a significantly higher complication rate (p = 0.02). History of previous surgery and surgical approach were not significantly associated with higher complication rates. On multivariate analysis, only the grade of spondylolisthesis (low vs high) was in the final best-fit model of factors associated with the occurrence of complications (p < 0.0001)., Conclusions: The rate of total complications for treatment of DS and IS in this series was 9.2%. The total percentage of patients with complications was 7.9%. On univariate analysis, the complication rate was significantly higher in patients with high-grade spondylolisthesis, a diagnosis of DS, and in older patients. Surgical approach and history of previous surgery were not significantly correlated with increased complication rates. On multivariate analysis, only the grade of spondylolisthesis was significantly associated with the occurrence of complications.

Abnormal thoracolumbar kyphosis in infants may be due to lumbar hypoplasia that resolves with development of upright posture. The cause of this deformity has not been previously identified. The goal of this study was to find whether excessive time in an upright posture while sleeping and sitting may play a role in the etiology of infantile thoracolumbar kyphosis. We retrospectively reviewed infants with the diagnosis of kyphosis from 2001 to 2005. Inclusion criteria were patients diagnosed prior to age 3 years without syndromic, neuromuscular, or congenital kyphosis and minimum 2-year follow-up. Serial radiographic evaluation was used to assess change in kyphotic deformity. Six infants with an average age of 7 months at the time of diagnosis were identified. All had marked thoracolumbar kyphosis with vertebral wedging and scalloping. Some had pseudosubluxation at the T12-L1 level. The initial average Cobb angle was 30° (normal, 0°-5°). Careful history revealed that all patients slept in an upright posture in addition to sitting while awake. All of the patients were observed following parental instruction in proper sleeping and sitting habits. At last follow-up, all patients had normal sagittal alignment with an average Cobb angle of 1.3°. Proper sleeping and sitting habits with good spine support is recommended for infantile thoracolumbar kyphosis with lumbar hypoplasia. Allowing "tummy time" during waking hours may help the paraspinal muscles gain strength to provide support to the spine. Radiographic evidence of vertebral body height restoration may be delayed for several years., (Copyright 2010, SLACK Incorporated.)

A novel matrix-free LDI MS platform using a thin film of patterned nanostructured gold, capped with methyl- and carboxy-terminated self-assembled monolayers (SAMs) is presented. Calibration on the matrix-free LDI surface was performed using a peptide standard mixture available for MALDI analysis. MS analysis for limit of detection was performed using angiotensin I peptide. Peptide fragments from standard protein digests of bovine serum albumin, bovine catalase, and bovine lactoperoxidase were used to carry out peptide mass fingerprinting analysis. Sequence coverage of each protein digest and the number of detected peptide fragments were compared with conventional MALDI MS on a standard MALDI plate. Versatility of the nanostructured gold LDI substrate is illustrated by performing MS analysis on a protein digest using different enzymes and by small molecule MS analysis.

Object: The purpose of this study was to evaluate the prospectively collected Scoliosis Research Society (SRS) database to assess the incidences of morbidity and mortality (M&M) in the operative treatment of degenerative lumbar stenosis, one of the most common procedures performed by spine surgeons., Methods: All patients who underwent surgical treatment for degenerative lumbar stenosis between 2004 and 2007 were identified from the SRS M&M database. Inclusion criteria for analysis included an age >or= 21 years and no history of lumbar surgery. Patients were treated with either decompression alone or decompression with concomitant fusion. Statistical comparisons were performed using a 2-sided Fisher exact test., Results: Of the 10,329 patients who met the inclusion criteria, 6609 (64%) were treated with decompression alone, and 3720 (36%) were treated with decompression and fusion. Among those who underwent fusion, instrumentation was placed in 3377 (91%). The overall mean patient age was 63 +/- 13 years (range 21-96 years). Seven hundred nineteen complications (7.0%), including 13 deaths (0.1%), were identified. New neurological deficits were reported in 0.6% of patients. Deaths were related to cardiac (4 cases), respiratory (5 cases), pulmonary embolus (2 cases), and sepsis (1 case) etiologies, and a perforated gastric ulcer (1 case). Complication rates did not differ based on patient age or whether fusion was performed. Minimally invasive procedures were associated with fewer complications and fewer new neurological deficits (p = 0.01 and 0.03, respectively)., Conclusions: The results from this analysis of the SRS M&M database provide surgeons with useful information for preoperative counseling of patients contemplating surgical intervention for symptomatic degenerative lumbar stenosis.

This paper presents design, microfabrication, and test of a microfluidic nebulizer chip for desorption electrospray ionization mass spectrometry (DESI-MS) in proteomic analysis. The microfluidic chip is fabricated using cyclic olefin copolymer (COC) substrates. The fluidic channels are thermally embossed onto a base substrate using a nickel master and then a top substrate is thermally bonded to seal the channels. Carbon ink embossed into the top COC substrate is used to established electrical connection between the external power supply and the liquid in the channel. The microfluidic chip to external capillary connection is fabricated using Nanoport() interconnection system. Preliminary leakage test was performed to demonstrate the interconnection system is leak-free and pressure test was performed to evaluate the burst pressure. Finally, the nebulizer chip was used to perform DESI-MS for analyzing peptides (BSA and bradykinin) and reserpine on the nanoporous alumina surface. DESI-MS performance of the microfluidic nebulizer chip is compared with that obtained using a conventional DESI nebulizer.

A gold coated nanoporous alumina surface was used for dual ionization mode mass spectrometric analysis using desorption electrospray ionization (DESI) and laser desorption ionization (LDI). DESI and LDI mass spectrometry (MS) from the nanoporous alumina surface were compared with conventional electrospray ionization (ESI) mass spectrometry and matrix assisted laser desorption ionization (MALDI) for analysis of tryptic digests of proteins. Combined use of DESI and LDI offer greater peptide coverage than either method alone and comparable peptide coverage as with dual MALDI and ESI. This dual ionization technique using a common platform with same sample spot demonstrates a potential time and cost-effective tool for improved shotgun proteomic analysis.

Shotgun proteomic analysis usually employs multidimensional separations with the first dimension most commonly being strong cation exchange (SCX) liquid chromatography (LC). SCX-LC is necessarily a serial process for preparation of multiple samples. Here, we apply a newly available tool, off-gel electrophoresis (OGE), for first-dimension separation of peptide mixtures from digests of cerebrospinal fluid (CSF), a complex and low total protein-containing sample. OGE first-dimension fractionation enabled identification of a total of 156 unique proteins compared to 115 identified in previous work using first-dimension SCX fractionation. OGE can be used to process multiple samples unattended with easy retrieval of the separated fractions. Thus, shotgun analysis using OGE as the first-dimension separation offers a significant advantage both in terms of sample throughput as well as increased numbers of identified proteins.

Immobilized metal affinity chromatography (IMAC) based on Fe (3+) or Ga (3+) chelation is the most widely employed technique for the enrichment of phosphopeptides from biological samples prior to mass spectrometric analysis. An IMAC resin geared mainly toward phosphoprotein enrichment, Pro-Q Diamond, has been assessed for its utility in phosphopeptide isolation. Using both single phosphoprotein tryptic digests of beta-casein and ovalbumin and synthetic mixtures composed of tryptic digests of phosphorylated and nonphosphorylated protein standards, the selectivity and sensitivity of Pro-Q Diamond resin in an immobilized metal affinity-reversed phase microcolumn format were compared to an alternate titanium dioxide approach. The biphasic microcolumn method was found to be superior to metal oxide-based phosphopeptide capture in biological samples of increasing complexity. The lower limit of mass spectrometric detection for the immobilized metal affinity-reversed phase microcolumn approach was determined to be 10 pmol of beta-casein monophosphorylated peptide in 20 microL of a solution of human serum protein digest (from 200 microg total serum protein after digestion and desalting).

This paper presents use of a nanoporous alumina surface for desorption electrospray ionization mass spectrometry (DESI MS). The DESI MS performance of the nanoporous alumina surface is compared with that of polymethylmethacrylate (PMMA), polytetrafluroethylene (PTFE) and glass, which are popular surfaces in DESI MS experiments. Optimized operating conditions were determined for each of these surfaces by studying the effects of flow rate, tip to surface and surface to MS capillary distance, and spray angle on the DESI MS performance. The analytes (reserpine and BSA tryptic digest) were analyzed on all the surfaces. The results show that the nanoporous alumina surface offers higher ion intensity and increased peptide detection as compared to the other surfaces. Additionally, comparison of ion intensities obtained from the nanoporus alumina and an alumina film confirms that improved performance is due to the inherent nature of the nanostructured surface. Limits of detection (LODs) were determined for the analytes on all the surfaces. It was observed that the nanoporous alumina surface offers improved limits of detection as compared to other surfaces. Another advantage of the nanoporous alumina surface is that it provides to faster analysis associated with rapid drying of liquid samples on the surface. Additionally, porous alumina surface can be used as a dual ionization platform for combined DESI/LDI analysis for further improved peptide detection in proteomic analysis.

A simple light-actuated microvalve using a quartz halogen illuminator with tungsten filament was introduced to manipulate flow path effectively in micro-total analysis systems, which reduces system complexity and the need for on-chip integration. The microvalve device in cyclic olefin copolymer (COC) microchip functions very well based on the thermo-responsive polymer, poly(N-isopropylacrylamide) (PNIPAAm), whose pressure-tolerance can be tuned by changing the mechanical strength of polymer monolith inside the microchannel with the choice of suitable amount of monomer and crosslinker. The response time and pressure resistance of the valve can be optimized by the tetrahydrofuran composition in the polymerization mixture as well. Very importantly, the microvalve can withstand the leakage pressure up to around 1350 psi, and its opening and closing response time is only 4.0 and 6.2 s respectively. Microchips with such valves will be very useful in drug delivery, chemical analysis and proteomic analysis.