Are Patients With Segmental Cervical Kyphosis Appropriate Candidates for Cervical Disc Arthroplasty (CDA)? A Clinical and Radiographic Analysis Compared to Anterior Cervical Discectomy and Fusion (ACDF).

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To compare the clinical and radiographic outcomes of Anterior Cervical Discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) in patients with preoperative segmental kyphosis. METHODS: Patients with segmental cervical kyphosis at the operative levels undergoing 1- or 2-level ACDF or CDA from 2017 to 2020 with 2 years of follow were identified. Patient demographics, perioperative data, complication rates, radiographic findings and reported outcomes were analyzed. RESULTS: A total of 48 patients met inclusion criteria and were included in our study (ACDF: n = 24, CDA: n = 24). Patient demographic data between the 2 cohorts was similar expect for proportion of males (ACDF: 62.5% vs CDA: 33.3%, P = .043). There was no statistical significance in the change of segmental lordosis (ACDF: +8.09° vs CDA: +5.88°, P = .075) between the preoperative and final postoperative period. Additionally, the change in cervical lordosis was similar between groups (ACDF:+ 9.86° vs CDA: +7.60°, P = .226). VAS scores were similar between the 2 groups at every follow-up interval. NDI scores were significantly different at the 6-month, 12 month and the final follow-up. Mean improvements between preoperative and final postoperative periods were statistically superior in the CDA cohort compared to the ACDF cohort (ACDF: 22.8 vs CDA: 24.1, P = .0375). CONCLUSION: CDA was superior to ACDF in regards to NDI scores following index procedure in patients with preoperative segmental cervical kyphosis. Those in the CDA cohort had similar complication rates, revision rates and radiographic outcomes as those who underwent ACDF.

An observer-blinded, cluster randomised trial of a typhoid conjugate vaccine in an urban South Indian cohort.

BACKGROUND: Typhoid fever causes nearly 110,000 deaths among 9.24 million cases globally and disproportionately affects developing countries. As a control measure in such regions, typhoid conjugate vaccines (TCVs) are recommended by the World Health Organization (WHO). We present here the protocol of a cluster randomised vaccine trial to assess the impact of introducing TyphiBEV® vaccine to those between 1 and 30 years of age in a high-burden setting. METHODS: The primary objective is to determine the relative and absolute rate reduction of symptomatic, blood-culture-confirmed S. Typhi infection among participants vaccinated with TyphiBEV® in vaccine clusters compared with the unvaccinated participants in non-vaccine clusters. The study population is residents of 30 wards of Vellore (a South Indian city) with participants between the ages of 1 and 30 years who provide informed consent. The wards will be divided into 60 contiguous clusters and 30 will be randomly selected for its participants to receive TyphiBEV® at the start of the study. No placebo/control is planned for the non-intervention clusters, which will receive the vaccine at the end of the trial. Participants will not be blinded to their intervention. Episodes of typhoid fever among participants will be captured via stimulated, passive fever surveillance in the area for 2 years after vaccination, which will include the most utilised healthcare facilities. Observers blinded to the participants' intervention statuses will record illness details. Relative and absolute rate reductions will be calculated at the end of this surveillance and used to estimate vaccine effectiveness. DISCUSSION: The results from our trial will allow countries to make better-informed decisions regarding the TCV that they will roll-out and may improve the global supplies and affordability of the vaccines. TRIAL REGISTRATION: Clinical Trials Registry of India (CTRI) CTRI/2022/03/041314. Prospectively registered on 23 March 2022 ( https://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=62548&EncHid=&userName=vellore%20typhoid ). CTRI collects the full WHO Trial Registration Data Set.

Burden of Typhoid and Paratyphoid Fever in India.

BACKGROUND: In 2017, more than half the cases of typhoid fever worldwide were projected to have occurred in India. In the absence of contemporary population-based data, it is unclear whether declining trends of hospitalization for typhoid in India reflect increased antibiotic treatment or a true reduction in infection. METHODS: From 2017 through 2020, we conducted weekly surveillance for acute febrile illness and measured the incidence of typhoid fever (as confirmed on blood culture) in a prospective cohort of children between the ages of 6 months and 14 years at three urban sites and one rural site in India. At an additional urban site and five rural sites, we combined blood-culture testing of hospitalized patients who had a fever with survey data regarding health care use to estimate incidence in the community. RESULTS: A total of 24,062 children who were enrolled in four cohorts contributed 46,959 child-years of observation. Among these children, 299 culture-confirmed typhoid cases were recorded, with an incidence per 100,000 child-years of 576 to 1173 cases in urban sites and 35 in rural Pune. The estimated incidence of typhoid fever from hospital surveillance ranged from 12 to 1622 cases per 100,000 child-years among children between the ages of 6 months and 14 years and from 108 to 970 cases per 100,000 person-years among those who were 15 years of age or older. Salmonella enterica serovar Paratyphi was isolated from 33 children, for an overall incidence of 68 cases per 100,000 child-years after adjustment for age. CONCLUSIONS: The incidence of typhoid fever in urban India remains high, with generally lower estimates of incidence in most rural areas. (Funded by the Bill and Melinda Gates Foundation; NSSEFI Clinical Trials Registry of India number, CTRI/2017/09/009719; ISRCTN registry number, ISRCTN72938224.).

Two-Attending Surgeon Teams Improve Outcomes of Single-Level Anterior Cervical Discectomy and Fusion.

Given the shift toward value-based healthcare, strategies that decrease risk in commonly performed procedures such as anterior cervical discectomy and fusion (ACDF) are of interest. The objective of this study was to analyze the effect of a two-attending surgeon team on the outcomes of patients undergoing single-level ACDF. A retrospective matched-cohort study of patients undergoing single-level ACDF for degenerative cervical spondylosis, with minimum 2-year follow-up was performed. Patients were subdivided into two cohorts: cases with procedures performed by one attending surgeon assisted by a resident physician and cases with procedures performed by an attending surgeon with another attending surgeon as first-assist. Patients were matched by age, sex, body mass index, smoking status, American Society of Anesthesia grade and Charlson Comorbidity Index. Perioperative data and complications were compared. Standard binomial and categorical comparative analysis were performed. Forty-two patients were included (21 in each group). There were 22 males and 20 females, with a mean age of 47.7 years and mean follow-up of 43.4 months. There were no differences in any demographic variable between groups, indicating successful matching. Cohort B had decreased anesthesia time (114.9 vs. 157.1 minutes, P < 0.001), operative time (58.1 vs. 98.9 minutes, P < 0.001) and blood loss (14.8 vs. 24.3 mL, P = 0.012). There were no significant differences in terms of post-operative complications including dysphagia, wound infection, neurologic or cardiovascular related complications. A two-attending surgeon team significantly reduces anesthesia time, surgical time, and blood loss in single-level ACDF procedures without an increase in complications or a decrease in fusion rates.

Human KCNQ5 de novo mutations underlie epilepsy and intellectual disability.

We identified six novel de novo human KCNQ5 variants in children with motor/language delay, intellectual disability (ID), and/or epilepsy by whole exome sequencing. These variants, comprising two nonsense and four missense alterations, were functionally characterized by electrophysiology in HEK293/CHO cells, together with four previously reported KCNQ5 missense variants (Lehman A, Thouta S, Mancini GM, Naidu S, van Slegtenhorst M, McWalter K, Person R, Mwenifumbo J, Salvarinova R; CAUSES Study; EPGEN Study; Guella I, McKenzie MB, Datta A, Connolly MB, Kalkhoran SM, Poburko D, Friedman JM, Farrer MJ, Demos M, Desai S, Claydon T. Am J Hum Genet 101: 65-74, 2017). Surprisingly, all eight missense variants resulted in gain of function (GOF) due to hyperpolarized voltage dependence of activation or slowed deactivation kinetics, whereas the two nonsense variants were confirmed to be loss of function (LOF). One severe GOF allele (P369T) was tested and found to extend a dominant GOF effect to heteromeric KCNQ5/3 channels. Clinical presentations were associated with altered KCNQ5 channel gating: milder presentations with LOF or smaller GOF shifts in voltage dependence [change in voltage at half-maximal conduction (ΔV50) = ∼-15 mV] and severe presentations with larger GOF shifts in voltage dependence (ΔV50 = ∼-30 mV). To examine LOF pathogenicity, two Kcnq5 LOF mouse lines were created with CRISPR/Cas9. Both lines exhibited handling- and thermal-induced seizures and abnormal cortical EEGs consistent with epileptiform activity. Our study thus provides evidence for in vivo KCNQ5 LOF pathogenicity and strengthens the contribution of both LOF and GOF mutations to global pediatric neurological impairment, including ID/epilepsy.NEW & NOTEWORTHY Six novel de novo human KCNQ5 variants were identified from children with neurodevelopmental delay, intellectual disability, and/or epilepsy. Expression of these variants along with four previously reported KCNQ5 variants from a similar cohort revealed GOF potassium channels, negatively shifted in V50 of activation and/or delayed deactivation kinetics. GOF is extended to KCNQ5/3 heteromeric channels, making these the predominant channels affected in heterozygous de novo patients. Kcnq5 LOF mice exhibited seizures, consistent with in vivo pathogenicity.

Long-term Outcomes of Minimally Invasive Lateral Lumbar Interbody Fusion in the Treatment of Adult Scoliosis.

The literature has shown the importance of long-term follow-up for adults with scoliosis treated surgically because complication and revision rates are high. The goal of this study was to determine long-term outcomes and complications of lateral lumbar interbody fusion (LLIF) with posterior instrumentation for adult patients with scoliosis. A retrospective review of our institution's database was performed to identify adult patients with scoliosis treated with LLIF between 2008 and 2013 with a minimum follow-up of 4 years. Medical records were reviewed for complications and revisions. Pre- and postoperative deformity Cobb angle measurements were taken as well as pelvic incidence (PI) and lumbar lordosis (LL). Functional outcome scores, including Oswestry Disability Index and visual analog scale score for back and leg pain, were assessed preoperatively and at follow-up. Standard binomial and categorical comparative analysis was performed. The 26 patients included had a mean age of 62 years, mean follow-up of 89 months, and mean of 1.8 levels per operation. Four patients (15.4%) required revisions. Mean deformity Cobb angle was 26° preoperatively and 14° postoperatively. Mean PI-LL mismatch was 11.7° preoperatively and 5.9° postoperatively. Nineteen (73%) patients had a PI-LL mismatch greater than 10° preoperatively, whereas only 2 (7.7%) had a mismatch postoperatively. Improvement was seen in all functional outcome scores. Long-term clinical results of LLIF for adults with deformity showed a low proportion of revision in the treatment of a condition with an established high rate of revision. The ability to reduce pelvic mismatch may further reduce the rate of revision. In this study, LLIF resulted in improved functional outcomes and patient satisfaction. [Orthopedics. 2022;45(3):e134-e139.].

Should we bridge the cervicothoracic junction in long cervical fusions? A meta-analysis and systematic review of the literature.

OBJECTIVE: Long posterior cervical decompression and fusion (PCF) is commonly performed to surgically treat patients with multilevel cervical pathology. In cases in which constructs may necessitate crossing the cervicothoracic junction (CTJ), recommendations for appropriate caudal fusion level vary in the literature. The aim of this study was to report the clinical and radiological outcomes of multilevel PCFs ending at C7 versus those crossing the CTJ. METHODS: A systematic search of PubMed, CINAHL Plus, and Scopus was conducted to identify articles that evaluated clinical and radiological outcomes of long PCFs that ended at C7 (cervical group) or crossed the CTJ (thoracic group). Based on heterogeneity, random-effects models of a meta-analysis were used to estimate the pooled estimates and the 95% confidence intervals. RESULTS: PCF outcome data of 1120 patients from 10 published studies were included. Compared with the cervical group, the thoracic group experienced greater mean blood loss (453.0 ml [95% CI 333.6-572.5 ml] vs 303.5 ml [95% CI 203.4-403.6 ml]), longer operative times (235.5 minutes [95% CI 187.7-283.3 minutes] vs 198.5 minutes [95% CI 157.9-239.0 minutes]), and a longer length of stay (6.7 days [95% CI 3.3-10.2 days] vs 6.2 days [95% CI 3.8-8.7 days]); however, these differences were not statistically significant. None of the included studies specifically investigated factors that led to the decision of whether to cross the CTJ. The cervical group had a mean fusion rate of 86% (95% CI 71%-94%) compared with the thoracic group with a rate of 90% (95% CI 81%-95%). Of patients in the cervical group, 17% (95% CI 10%-28%) required revision surgery compared with 7% (95% CI 4%-13%) of those in the thoracic group, but this difference was not statistically significant. The proportion of patients who experienced complications in the cervical group was found to be 28% (95% CI 12%-52%) versus 14% (95% CI 7%-26%) in the thoracic group; however, this difference was not statistically significant. There was no significant difference (no overlap of 95% CIs) in the incidence of adjacent-segment disease, pseudarthrosis, or wound-related complications between groups. CONCLUSIONS: This meta-analysis suggests similar clinical and radiographic outcomes in multilevel PCF, regardless of inclusion of the CTJ. The lowest instrumented level did not significantly affect revision rates or complications. The ideal stopping point must be tailored to each patient on an individualized basis.

Comparing Mid-Term Outcomes Between ACDF and Minimally Invasive Posterior Cervical Foraminotomy in the Treatment of Cervical Radiculopathy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare minimally invasive posterior cervical foraminotomy (MI-PCF) and anterior cervical discectomy and fusion (ACDF) in the treatment of unilateral cervical radiculopathy. SUMMARY OF BACKGROUND DATA: MI-PCF has been shown to be equally effective as ACDF in treating cervical radiculopathy due to foraminal stenosis and similar pathologies. Additionally, it has been hypothesized that preserving motion and avoiding fusion reduces risk for adjacent segment disease, but potentially increases risk for subsequent revision to an ACDF. With similar short-term outcomes and substantial advantages, MI-PCF may be an effective alternative to ACDF for addressing appropriate cervical pathology. METHODS: A retrospective review was performed to identify patients between 2009 and 2013 who underwent ACDF or MI-PCF with a minimum follow-up of 7 years. Demographic data was recorded. Revision rates and average time to revision between cohorts were compared. Clinical outcomes were assessed at each follow-up visit with Neck Disability Index and Visual Analog Scale for neck and Visual Analog Scale for arm pain scores. All complications were reviewed. Standard binomial and categorical comparative analysis were performed. RESULTS: A total of 251 consecutive patients were included (205 ACDF, 46 MI-PCF). Mean follow-ups for the ACDF and MI-PCF groups were 98.3 and 95.9 months, respectively. Complication rates were 2.9% and 2.2% for the ACDF and MI-PCF cohorts, respectively (P = 0.779). Revision rates were 7.8% for the ACDF cohort and 8.7% for the MI-PCF cohort (P = 0.840). Both cohorts experienced significant improvements in their clinical scores compared with their preoperative values. Final Visual Analog Scale for neck pain (ACDF: 2.6; MI-PCF: 1.6) and Visual Analog Scale for arm pain (ACDF: 1.1; MI-PCF: 0.4) scores differed significantly at final follow-up (P =  < 0.001; P =  < 0.001). CONCLUSION: MI-PCF is a safe and effective alternative to ACDF in the treatment of cervical radiculopathy, demonstrating substantial benefit. After final follow-up, MI-PCF demonstrated superior improvements in Visual Analog Scale scores, without increased complication or revision rates.Level of Evidence: 3.

Does Percutaneous Lumbosacral Pedicle Screw Instrumentation Prevent Long-Term Adjacent Segment Disease after Lumbar Fusion?

STUDY DESIGN: Retrospective cohort study. PURPOSE: To assess long-term clinical outcomes of adjacent segment disease (ASD) in patients who underwent lumbar interbody fusion with percutaneous pedicle screw (PS) instrumentation. OVERVIEW OF LITERATURE: ASD is a well-known sequela of spinal fusion, and is reported to occur at a rate of 2%-3% per year. There is debate as to whether ASD is a result of the instrumentation and fusion method or is the natural history of the patient's disease. Minimally invasive percutaneous PS augmentation of lumbar interbody fusion aims to prevent the disruption of posterior soft tissue stabilizers. METHODS: From 2004-2014, 419 consecutive patients underwent anterior, lateral, or minimally invasive transforaminal lumbar interbody fusion with percutaneous PS placement at a single institution. The mean follow-up was 4.5 years. The primary outcome measure was reoperation due to ASD. Patients were divided into two cohorts: those who underwent revision surgery secondary to ASD and those who did not require further surgery. Radiographic parameters were performed using postoperative radiographs. Patients with a pelvic incidence-lumbar lordosis (PI-LL) mismatch >10° were noted. RESULTS: Revision proportion secondary to ASD was 4.77% (n=20). Mean time to revision surgery was 2.5 years. Revision rate secondary to ASD was 1.1% per year. Patients who developed ASD were younger than those who did not (50.5 vs. 56.9 years, p=0.015). There was no difference in number of levels fused between cohorts. Revision proportion secondary to ASD was similar between approaches (anterior, lateral, minimally invasive). There was no significant difference in PI-LL mismatch between those who underwent revision for ASD and those who did not (22.2% vs. 18.8%, p=0.758). CONCLUSIONS: ASD rates in patients who underwent percutaneous PS placement were lower than those previously published after open PS placement, possibly related to greater preservation of the posterior stabilizing elements of the lumbar spine.

Healthcare Utilization Survey in the Hybrid Model of the Surveillance for Enteric Fever in India (SEFI) Study: Processes, Monitoring, Results, and Challenges.

BACKGROUND: Lack of reliable data in India drove the "Surveillance of Enteric Fever in India" (SEFI) concept. Hybrid surveillance, combining facility-based surveillance for the crude incidence, and a community-based healthcare utilization survey (HCUS) to calculate the factor needed to arrive at the adjusted incidence, was used in 6 sites. The HCUS aimed to determine the percentage of utilization of study facilities by the catchment population for hospitalizations due to febrile illness. METHODS: Population proportional to size sampling and systematic random sampling, in 2 stages, were used to survey 5000 households per site. Healthcare utilization was assessed. RESULTS: Febrile illness accounted for 20% of admissions among 137 990 individuals from 30 308 households. Only 9.6%-38.3% of those admitted with febrile illness sought care in the study hospitals. The rate of rural utilization of the private sector for hospitalization was 67.6%. The rate of hospitalization for febrile illness, per 1000 population, ranged from 2.6 in Manali to 9.6 in Anantapur; for 25.8% of the deaths associated with febrile illness, no facility was used before death. CONCLUSIONS: One in 5 hospitalizations were associated with fever. Rural utilization of the private sector for hospitalization due to febrile illness was more than that of the public sector. Healthcare utilization patterns for hospital admissions due to febrile illness varied across sites. A meticulously performed HCUS is pivotal for accurate incidence estimation in a hybrid surveillance. CLINICAL TRIALS REGISTRATION: ISRCTN72938224.

Disordered autonomic function during exposure to moderate heat or exercise in a mouse model of Dravet syndrome.

OBJECTIVE: To examine autonomic regulation of core body temperature, heart rate (HR), and breathing rate (BR) in response to moderately elevated ambient temperature or moderate physical exercise in a mouse model of Dravet syndrome (DS). METHODS: We studied video-EEG, ECG, respiration, and temperature in mice with global heterozygous Scn1a knockout (KO) (DS mice), interneuron specific Scn1a KO, and wildtype (WT) mice during exposure to increased environmental temperature and moderate treadmill exercise. RESULTS: Core body temperatures of WT and DS mice were similar during baseline. After 15 mins of heat exposure, the peak value was lower in DS than WT mice. In the following mins of heat exposure, the temperature slowly returned close to baseline level in WT, whereas it remained elevated in DS mice. KO of Scn1a in GABAergic neurons caused similar thermoregulatory deficits in mice. During exercise, the HR increase was less prominent in DS than WT mice. After exercise, the HR was significantly more suppressed in DS. The heart rate variability (HRV) was lower in DS than WT mice during baseline and higher in DS during exercise-recovery periods. SIGNIFICANCE: We found novel abnormalities that expand the spectrum of interictal, ictal, and postictal autonomic dysregulation in DS mice. During mild heat stress, there was a significantly blunted correction of body temperature, and a less suppression of both HR and respiration rate in DS than WT mice. These effects were seen in mice with selective KO of Scn1A in GABAergic neurons. During exercise stress, there was diminished increase in HR, followed by an exaggerated HR suppression and HRV elevation during recovery in DS mice compared to controls. These findings suggest that different environmental stressors can uncover distinct autonomic disturbances in DS mice. Interneurons play an important role in thermoregulation. Understanding the spectrum and mechanisms of autonomic disorders in DS may help develop more effective strategies to prevent seizures and SUDEP.

Thyrotoxic Periodic Paralysis: A Spine Consultation.

As a consultant, the orthopaedic spine surgeon is often asked to evaluate patients with acute-onset extremity weakness. In some cases, patient's deficits can be attributed to nonspinal pathology; therefore, it is important to be aware of nonorthopaedic diagnoses when evaluating these patients. We report a case of thyrotoxic periodic paralysis that was initially confused by the consulting service with spinal pathology. A 32-year-old Hispanic man presented to our emergency department with rapid onset of lower extremity weakness. The consulting team ordered CT of the cervical and lumbar spine, as well as MRI of the lumbar spine which was aborted due to the patient's worsening tachycardia and chest pain. The spine service was subsequently consulted to evaluate the patient. Review of the metabolic panel revealed a low potassium, and additional testing led to the eventual diagnosis of thyrotoxic periodic paralysis. After correction of the patient's potassium, his weakness rapidly resolved, and no additional spinal workup was pursued. We describe this patient's presentation and outline the differential diagnosis for acute, nontraumatic extremity weakness, including both orthopaedic and other medical causes, that the spine surgeon should be aware of when evaluating patients with extremity weakness.

Minimally Invasive Posterior Cervical Foraminotomy as an Alternative to Anterior Cervical Discectomy and Fusion for Unilateral Cervical Radiculopathy: A Systematic Review and Meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: The aim of this study was to evaluate clinical outcomes, complications, and reoperations of minimally invasive posterior cervical foraminotomy (MI-PCF) for unilateral cervical radiculopathy without myelopathy, in comparison to anterior cervical decompression and fusion (ACDF). SUMMARY OF BACKGROUND DATA: ACDF is a standard treatment for cervical radiculopathy secondary to lateral disc herniation or foraminal stenosis. Recent studies have suggested MI-PCF to be an effective alternative to ACDF. However, concern for reoperation and whether similar improvements in clinical outcomes can be achieved has led to a debate in the literature. METHODS: We comprehensively searched PubMed, CINAHL Plus, and SCOPUS utilizing terms related to MI-PCF. Two independent reviewers assessed potential studies and extracted data on clinical outcome scores (neck disability index [NDI], visual analog scale [VAS]-neck, and VAS-arm), reoperation proportion, and complications. Studies included were on noncentral cervical pathology, published in the last 10 years, had a sample size of >10 patients, and reported data on minimally invasive techniques for posterior cervical foraminotomy. Heterogeneity and publication bias analyses were performed. The pooled proportions of each outcome were compared to those of ACDF obtained from two previously published studies. RESULTS: Fourteen studies were included with data of 1216 patients. The study population was 61.8% male, with a mean age of 51.57 years, and a mean follow-up of 30 months. MI-PCF resulted in a significantly greater improvement in VAS-arm scores compared to ACDF, and similar improvements in VAS-neck and NDI scores. Proportions of complications and reoperations were similar between the two cohorts. The most common complications were transient neuropraxia, wound-related, and durotomy. CONCLUSION: Our findings suggest that MI-PCF may be utilized as a safe and effective alternative to ACDF in patients with unilateral cervical radiculopathy without myelopathy, without concern for increased reoperations or complications. LEVEL OF EVIDENCE: 3.

Risk Factors for Pseudarthrosis in Minimally-Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort study (level of evidence: 4). PURPOSE: To describe the potential comorbid, operative, and radiographic risk factors for the development of clinically-relevant pseudarthrosis following minimally-invasive transforaminal lumbar interbody fusion (MIS-TLIF). OVERVIEW OF LITERATURE: MIS-TLIF has shown long-term clinical outcomes with decreased perioperative morbidity and earlier return to work, similar to those of open TLIF. However, unsuccessful fusion still remains a concern. The impacts of various patient, operative, and radiographic risk factors have not been evaluated for their potential association with pseudarthrosis related to MIS-TLIF. METHODS: Between 2012 and 2015, 204 consecutive patients underwent one or two-level MIS-TLIF at St. Joseph's University Medical Center, Paterson, NJ, USA; they had a minimum of 1 year of follow-up. The patients were divided into two cohorts: those who developed clinically-relevant pseudarthrosis and those who did not. Clinically-relevant pseudarthrosis was determined by both evidence on computed tomography and presence of continued clinical symptoms at 1-year follow-up. RESULTS: Revision surgery was the only identified non-radiographic factor associated with pseudarthrosis. Disc angle had the highest (R 2=0.8), followed by anterior disc height (R 2=0.79). Although posterior disc height and the ratio of anterior to posterior disc height showed a marked relationship with the outcome, the R 2-values were <0.3, thus indicating a less-strong correlation. The overall pseudarthrosis rate was 8%. No statistically significant differences were identified between the two cohorts with respect to mean age, sex, medical comorbidities, smoking status, or number of levels fused. CONCLUSIONS: Clinically-relevant pseudarthrosis is not uncommon following MIS-TLIF. In the current study, undergoing revision surgery, disc angle, and anterior disc height were observed to be associated with clinically-relevant pseudarthrosis. This study demonstrated that the patient population may benefit from an alternate approach.

Short-Segment Fixation With Percutaneous Pedicle Screws in the Treatment of Unstable Thoracolumbar Vertebral Body Fractures.

Clinical care of patients with unstable thoracolumbar vertebral body fractures may be challenging, especially in the setting of polytrauma patients who require other acute intervention. Compared with the traditional open approach, percutaneous short-segment fixation constructs place less surgical burden on patients regarding operative time and blood loss. Between 2008 and 2012, 32 patients with a mean age of 49 years (range, 19-80 years) underwent percutaneous short-segment fixation at the authors' institution and had a minimum of 6 months of complete clinical and radiographic follow-up. Load-sharing classification scores were determined. Outcomes evaluated included anterior body height, posterior body height, local kyphosis, regional kyphosis, thoracolumbar junctional kyphosis, mean operative time, and total blood loss. Standard binomial and categorical comparative analyses were performed. All load-sharing classification scores were 7 or less, and 11 of the 32 patients were polytrauma patients requiring surgery. No difference was seen between preoperative and late measurements of anterior body height, posterior body height, local kyphosis, regional kyphosis, or thoracolumbar junctional kyphosis. There were no complications, revisions, or anterior corpectomies. Only 2 patients (6%) underwent elective removal of hardware at 1 year. Mean operative time was 43 minutes (range, 33-56 minutes), and mean estimated blood loss was less than 50 mL. Percutaneous short-segment fixation prevented loss of vertebral body height and progression of kyphosis in the treatment of unstable thoracolumbar fractures with load-sharing classification scores of 7 or less. This study shows that these fractures with a load-sharing classification score of 6 and 7 may be stabilized using fewer screws than traditional methods in some patients and allow polytrauma patients to undergo other acute treatment. [Orthopedics. 2018; 41(6):e802-e806.].

Minimally invasive posterior cervical foraminotomy with tubes to prevent undesired fusion: a long-term follow-up study.

OBJECTIVE: The objective of this study was to compare anterior cervical discectomy and fusion (ACDF) and minimally invasive posterior cervical foraminotomy (MI-PCF) with tubes for the treatment of cervical radiculopathy in terms of the 1) overall revision proportion, 2) index and adjacent level revision rates, and 3) functional outcome scores. METHODS: The authors retrospectively reviewed the records of consecutive patients who had undergone ACDF or MI-PCF at a single institution between 2009 and 2014. Patients treated for cervical radiculopathy without myelopathy and with a minimum 2-year follow-up were compared according to the procedure performed for their pathology. Primary outcome measures included the overall rate of revision with fusion and overall revision proportion as well as the rate of index and adjacent level revisions per year. Secondarily, self-reported outcome measures-Neck Disability Index (NDI) and visual analog scale (VAS) for arm (VASa) and neck (VASn) pain-at the preoperative and postoperative evaluations were analyzed. Standard binomial and categorical comparative analyses were performed. RESULTS: Forty-nine consecutive patients were treated with MI-PCF, and 210 consecutive patients were treated with ACDF. The mean follow-up for the MI-PCF cohort was 42.9 ± 6.6 months (mean ± SD) and for the ACDF cohort was 44.9 ± 10.3 months. There was no difference in the overall revision proportion between the two cohorts (4 [8.2%] of 49 MI-PCF vs. 12 [5.7%] of 210 ACDF, p = 0.5137). There was no difference in the revision rate per level per year (3.1 vs. 1.7, respectively, p = 0.464). Moreover, there was no difference in the revision rate per level per year at the index level (1.8 vs. 0.7, respectively, p = 0.4657) or at an adjacent level (1.3 vs. 1.1, p = 0.9056). Neither was there a difference between the cohorts as regards the change from preoperative to final postoperative functional outcome scores (NDI, VASa, VASn). CONCLUSIONS: Minimally invasive PCF for the treatment of cervical radiculopathy demonstrates rates of revision at the index and adjacent levels similar to those following ACDF. In order to confirm the positive efficacy and cost analysis findings in this study, future studies need to extend the follow-up and show that the rate of revision with fusion does not increase substantially over time.

Incidence of Neuraxial Abnormalities Is Approximately 8% Among Patients With Adolescent Idiopathic Scoliosis: A Meta-analysis.

BACKGROUND: Several studies have sought to address the role of routine preoperative MRI in patients with adolescent idiopathic scoliosis (AIS) undergoing deformity correction. Despite similar results regarding the prevalence of neuraxial anomalies detected on MRI, published conclusions conflict and give opposing recommendations. Lack of consensus has led to important variations in use of MRI before spinal surgery for patients with AIS. QUESTIONS/PURPOSES: This systematic review and meta-analysis of studies about patients with AIS evaluated (1) the overall proportion of neuraxial abnormalities; (2) the patient factors and curve characteristics that may be associated with abnormalities; and (3) the proportion of patients who underwent neurosurgical intervention before scoliosis surgery and the kinds of neuraxial lesions that were identified. METHODS: We performed a search of four electronic databases (PubMed, EMBASE, CINAHL Plus, and SCOPUS) utilizing search terms related to routine MRI and AIS, yielding 206 articles. Studies included had at least 20 participants, patients with ages 11 to 21 years, and a Methodological Index for Non-Randomized Studies (MINORS) study quality score of 8 and 16 points for noncomparative and comparative studies, respectively. Non-English manuscripts, animal studies, and those that did not include patients with AIS solely were excluded. Eighteen articles with 4746 patients were included for analysis of the overall proportion of neuraxial abnormalities, 12 articles with 3028 patients for analysis by sex, eight articles with 1603 patients for right main thoracic curve, eight articles with 665 patients for a left main thoracic curve, and 13 articles with 3063 patients and 230 (7.5%) abnormalities for number of neurosurgical interventions before scoliosis correction. The mean MINORS score for studies included was 14 (range, 10-20). Each study was analyzed for the proportion of patients identified with neuraxial abnormalities and associations with specific demographics. We determined the proportion of patients who underwent surgical interventions before scoliosis surgery as well as the types of neuraxial lesions identified. The articles were assessed for heterogeneity and publication bias. Because all groups were determined to be heterogeneous, a random-effects model was used for each group in this meta-analysis; with this analysis, an overlap of 95% confidence intervals suggests no difference at the p < 0.05 level, but this analytic approach does not provide p values. RESULTS: The pooled proportion of neuraxial abnormalities detected on MRI was 8% (95% confidence interval [CI], 6%-12%). With the numbers available, we found no difference in the proportion of male and female patients with neuraxial abnormalities (18% [95% CI, 11%-29%] versus 9% [95% CI, 6%-12%], respectively). Likewise, there was no difference in the proportion of pooled neuraxial abnormalities in right and left curves (9% [95% CI, 6%-14%] versus 15% [95% CI, 5%-35%], respectively). In the subset of abnormalities analyzed for number of neurosurgical interventions before scoliosis correction, the pooled proportion showed that 33% (95% CI, 24%-43%) underwent neurosurgical intervention before deformity correction. The most common abnormalities of the 367 found on MRI were syringomyelia in 127 patients (35%), Arnold-Chiari Type 1 malformation with syrinx in 103 patients (28%), and isolated Arnold-Chiari Type 1 malformation in 91 patients (25%). CONCLUSIONS: The proportion of patients with AIS who have neuraxial abnormalities is high (8%) and a large number undergo surgical intervention before scoliosis reconstruction. We did not find any particular demographic variables that indicated an increased risk of abnormality. Clinicians should consider advanced imaging before surgical intervention in the treatment of a patient with an idiopathic diagnosis. Preventable variables need to be identified by future studies to establish a better working treatment protocol for these patients. LEVEL OF EVIDENCE: Level III, diagnostic study.

Clinical Differences Between Monomicrobial and Polymicrobial Vertebral Osteomyelitis.

Little literature exists examining differences in presentation and outcomes between monomicrobial and polymicrobial vertebral infections. Seventy-nine patients treated for vertebral osteomyelitis between 2001 and 2011 were reviewed. Patients were divided into monomicrobial and polymicrobial cohorts based on type of infection. Various characteristics were compared between the 2 groups. The 26 patients with a polymicrobial infection were older and had a higher mortality rate, lower clearance of infection, larger infection, more vertebral instability, higher erythrocyte sedimentation rate at presentation, and longer mean length of stay. There were no significant differences in Oswestry Disability Index scores at final follow-up, but there were differences in presentation and clinical outcomes between monomicrobial and polymicrobial vertebral osteomyelitis. Patients may benefit from counseling regarding their disease type and potential prognosis. [Orthopedics. 2017; 40(2):e370-e373.].

Guillain-Barré syndrome following elective spine surgery.

PURPOSE: There is a paucity of literature describing Guillain-Barré syndrome (GBS) in the elective orthopedic patient. We aim to report one such case following spine surgery. METHODS: A morbidly obese 52-year-old male developed diminished reflexes as well as left upper and lower extremity weakness following surgical decompression and fusion at L4-5. The patient had persistent weakness and progressed to areflexia, at which point urgent lumbar puncture supported a diagnosis of GBS. RESULTS: The patient was promptly started on intravenous immunoglobulin and made significant clinical improvement with near-complete resolution of symptoms by 3-month follow-up visit. By the sixth month, he was able to function and ambulate without a cane. GBS is a rare and potentially critical cause of diminished reflexes and weakness in the post-operative elective orthopedic patient. We propose that morbid obesity may have contributed to the patient's susceptibility of developing GBS following surgery. CONCLUSION: Neurologic symptoms of this autoimmune condition may also mimic the clinical picture of an elective spine patient, thus confounding diagnosis. If imaging cannot explain exam findings or new neurologic symptoms post-operatively, rare disease processes should be considered in the differential diagnosis.