Impact of smoking on postoperative complications after anterior cervical discectomy and fusion

The relationship between smoking and the risk of postoperative complications among anterior cervical discectomy and fusion (ACDF) patients remains uncertain. We compared the postoperative complication rates following ACDF surgery among non-smokers, current smokers, and ever-smokers. Baseline and outcome data were obtained from the 2005- to 2014 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database for patients over the age of 18 who underwent non-emergent ACDF surgery. Information on current smoking and ever-smoking status was extracted. Outcomes included development of at least one complication, development of a major complication, in-hospital mortality, and length of stay. ACDF patients were either current smokers (7847, 30.3%) or not current smokers (18,022, 69.7%); 33.0% of all patients (n = 8542) had ever smoked. Current smoking status was not associated with increased odds of any one complication (P = 0.584) or any major complication (P = 0.138). In addition, using the number of pack-years as the primary independent variable, multivariate logistic regression analysis revealed that the number of pack-years was not significantly associated with greater odds of developing any one complication (P = 0.276) or any major complication (P = 0.334). However, ever-smoker status did present significantly higher odds of any major complication (OR, 1.333; 95% CI 1.007–1.764; P = 0.044) than for non-smokers. These results suggest that any patient with a prior smoking history should be considered a higher risk surgical candidate when attempting ACDF.     

Anterior cervical discectomy plus intervertebral polyetheretherketone cage fusion over three and four levels without plating is safe and effective long-term

Anterior cervical discectomy and fusion (ACDF) is an established treatment for single-level cervical spondylotic myelopathy and radiculopathy, yet its stand-alone use for multi-level disease of the subaxial cervical spine remains controversial. We report a prospectively studied case series of 30 patients receiving polyetheretherketone (PEEK) cage fusion over three and four cervical levels without anterior plating. Seven (23.3%) four-level procedures (all C3 to C7) were performed, the other 23 (76.7%) being three-level, with 19 (64.4%) at C4 to C7 and four (12.3%) at C3 to C6. Long-term follow-up of more than 2 years was available in 67% of patients. This cohort showed statistically significant improvements in visual analogue score for neck pain (p = 0.0006), arm pain (p = 0.0003) and Japanese Orthopaedic Association myelopathy score (p = 0.002). Fused segment heights increased by 0.6–1.1%. Adjacent segment disease requiring ACDF at C3–4 was seen in 6.7% of patients (one after trauma) at a mean follow-up of 62 months. Same segment recurrence requiring posterior decompression with instrumented fusion was found in 10% of patients at a mean follow-up of 49 months, only one of whom had radiological evidence of cage subsidence. The results suggest the procedure is safe and effective with potentially less morbidity than anterior plating, shorter inpatient stays than posterior approaches, acceptable same segment recurrence and lower than predicted adjacent segment disease rates.     

Comparison of perioperative complications following staged versus one-day anterior and posterior cervical decompression and fusion crossing the cervico-thoracic junction

IntroductionMultilevel cervical pathology may be treated via combined anterior cervical decompression and fusion (ACDF) followed by posterior spinal instrumented fusion (PSIF) crossing the cervico-thoracic junction.The purpose of the study was to compare perioperative complication rates following staged versus same day ACDF combined with PSIF crossing the cervico-thoracic junction.Material and methodsA retrospective review of consecutive patients undergoing ACDF followed by PSIF crossing the cervico-thoracic junction at a single institution was performed.Patients underwent either same day (group A) or staged with one week interval surgeries (group B). The minimum follow-up was 12 months.ResultsThirty-five patients (14 females and 21 males) were analyzed. The average age was 60 years (37–82 years). There were 12 patients in group A and 23 in group B. Twenty-eight complications noted in 14 patients (40%) included: dysphagia in 13 (37%), dysphonia in 6 (17%), post-operative reintubation in 4 (11%), vocal cords paralysis, delirium, superficial incisional infection and cerebrospinal fluid leakage each in one case. Significant differences comparing group A vs. B were found in: the number of levels fused posteriorly (5 vs. 7; p = 0.002), total amount of intravenous fluids (3233 ml vs. 4683 ml; p = 0.03), length of hospital stay (10 vs. 18 days; p = 0.03) and transfusion of blood products (0 vs. 9 patients). Smoking and cervical myelopathy were the most important risk factors for perioperative complications regardless of the group.ConclusionsStaging anterior cervical decompression and fusion with posterior cervical instrumented fusion 1 week apart does not decrease the incidence of perioperative complications.     

Outcomes of single-level cervical disc arthroplasty versus anterior cervical discectomy and fusion

Several studies have established the short-term safety and efficacy of cervical disc arthroplasty (CDA) as compared to anterior cervical discectomy and fusion (ACDF). However, few single-center comparative trials have been performed, and current studies do not contain large numbers of patients. We retrospectively reviewed all patients from a single military tertiary medical center between August 2008 to August 2012 who underwent single-level CDA or single-level ACDF and compared their clinical outcomes and complications. A total of 259 consecutive patients were included in the study, 171 patients in the CDA group with an average follow-up of 9.8 (±9.9) months and 88 patients in the ACDF group with an average follow-up of 11.8 (±9.6) months. Relief of pre-operative symptoms was 90.1% in the CDA group and 86.4% in the ACDF group with rates of return to full pre-operative activity of 93.0% and 88.6%, respectively. Patients who underwent CDA had a higher rate of persistent posterior neck pain (15.8% versus 12.5%), and patients who underwent ACDF were at risk for symptomatic pseudarthrosis at a rate of 3.4%. Reoperation rates were higher in the ACDF group (5.7% versus 3.5%). To our knowledge, this review is the largest, non-funded, comparison study between single-level CDA and single-level ACDF. This study demonstrates that CDA is a safe and reliable alternative to ACDF in the treatment of cervical radiculopathy and myelopathy resulting from spondylosis and acute disc herniation.     

Successful anterior fusion following posterior cervical fusion for revision of anterior cervical discectomy and fusion pseudarthrosis

Pseudarthrosis occurs after approximately 2–20% of anterior cervical discectomy and fusion (ACDF) procedures; it is unclear if posterior or anterior revision should be pursued. In this study, we retrospectively evaluate the outcomes in 22 patients with pseudarthrosis following ACDF and revision via posterior cervical fusion (PCF). Baseline demographics, preoperative symptoms, operative data, time to fusion failure, symptoms of pseudarthrosis, and revision method were assessed. Fusion outcome and clinical outcome were determined at last follow-up (LFU). Thirteen females (59%) and 9 (41%) males experienced pseudarthrosis at a median of 11 (range: 3–151) months after ACDF. Median age at index surgery was 51 (range: 33–67) years. All patients with pseudarthrosis presented with progressive neck pain, with median visual analog scale (VAS) score of 8 (range: 0–10), and/or myeloradiculopathy. Patients with pseudarthrosis <12 months compared to >12 months after index surgery were older (p = 0.013), had more frequent preoperative neurological deficits (p = 0.064), and lower baseline VAS scores (p = 0.006). Fusion was successful after PCF in all patients, with median time to fusion of 10 (range: 2–14) months. Eighteen patients fused both anteriorly and posteriorly, two patients fused anteriorly only, and two patients fused posteriorly only. Median VAS neck score at LFU significantly improved from the time of pseudarthrosis (p = 0.012). While uncommon, pseudarthrosis may occur after ACDF. All patients achieved successful fusion after subsequent posterior cervical fusion, with 91% fusing a previous anterior pseudarthrosis after posterior stabilization. Neck pain significantly improved by LFU in the majority of patients in this study.     

Adjacent segment disease requiring reoperation in cervical total disc arthroplasty: A literature review and update

Objective: To evaluate the difference in rate of reoperation for adjacent segment disease (ASD) between anterior cervical decompression and fusion (ACDF) and total disc replacement (TDR). Method: A systematic review of literature was performed using PubMed, clinicaltrials.gov, and various other search engines. Nine studies met the inclusion criteria and were used to report an estimated overall rate of reoperation secondary to ASD for both ACDF and TDR. Results: Forty-six clinical trials were identified after the initial search, and 9 studies met our inclusion criteria. Although the data was not pooled due to significant variation in level of evidence and length of follow-up, the overall rate of reoperation for ASD in the TDR cohort of patients analyzed in our review was 3.1% (range: 0–7.1%) with a follow-up between 24 and 80 months. In contrast, the reoperation rate for ASD in the ACDF control was 6.0% (range: 1.0–11.9%). Conclusion: The average reoperation rate for ASD was 3.1% for the TDR across all studies, which was lower than the reoperation rate of 6.0% in the ACDF group. Further studies and follow-up data are still needed to determine if cervical TDR preserves adjacent segment motion more efficiently than the natural history of the disease, and if it will be a durable option when compared to the already excellent results of ACDF.     

Effect of patient’s sex on early perioperative outcomes following anterior cervical discectomy and fusion

ObjectiveDifferences in morbidity and mortality measures between males and females have been demonstrated for a variety of spinal surgeries, however, studies of anterior cervical discectomy and fusion (ACDF) are limited. To investigate the impact of sex on 30-day perioperative outcomes of ACDF.MethodsRetrospective 1:1 propensity score-matched cohort study. Patients who underwent ACDF between 2016 and 2018 were reviewed from the ACS-NSQIP database. Propensity score matching and subgroup analysis were used.Results21,180 patients met inclusion criteria. 11,194 patients underwent single-level ACDF and 9986 patients underwent multi-level ACDF. In the single-level group, there were 6168 (55.1%) males and 5026 (44.9%) females. In the multi-level group, there were 5033 (50.4%) males and 4953 (49.6%) females. In both single/multi-level groups, females were more likely to be of older age, be functionally dependent, and have higher BMI and lower preoperative hematocrit level. Males were more likely to be Caucasian, smokers, have myelopathy, diabetes mellitus, hypertension and bleeding disorders. In both single/multi-level groups, except for the higher incidence of urinary tract infection (UTI) in females and myocardial infarction (MI) in males, there were no significant differences in morbidity and mortality between males and females.ConclusionsSeveral differences in demographics and baseline health status exist between males and females undergoing ACDF. When attempting to control for comorbid conditions, we found that sex by itself is not an independent risk factor for higher perioperative morbidity or mortality in patients undergoing ACDF, except for the higher incidence of UTI in females and MI in males. These results are important findings for clinicians and spine surgeons while counseling patients undergoing this type of procedure.     

Comparison of outpatient and inpatient spine surgery patients with regards to obesity,comorbidities and readmission for infection

Outpatient spine surgery is becoming popular because of its substantial economic advantages. We retrospectively studied 97 spine surgery outpatients and 578 inpatients who had proceeded through a common process of surgical venue selection. No differences (p > 0.05) were found in gender, race, obesity rate (46.9% versus [vs.] 42.9%), hypertension (9.7% vs. 8.8%), chronic obstructive pulmonary disease (11.8% vs. 13.5%), and history of stroke (1.9% vs. 2.5%). However, age was statistically different between inpatients (55 years) and outpatients (49 years) (p < 0.001). The prevalence of diabetes mellitus (19% vs. 10%), congestive heart disease (19.7% vs. 1.3%), coronary artery procedures (15.9% vs. 3.8%), and use of antidepressants (25.4% vs. 11.6%) was higher in the inpatient group (p < 0.05). There were more comorbidities in the inpatient cohort of each spine surgery type except for chronic obstructive pulmonary disease (COPD) and history of stroke in the outpatient cervical surgery group (p < 0.05). Among outpatients, only one patient (～1%) had postoperative infection while among the inpatients, 16 patients had postoperative infections (2.8%) (p > 0.05). All seven patients readmitted due to infection were obese (body mass index ?30). Obese patients in the inpatient cohort had higher chronic disease rates. Comorbidities are the main determinants of inpatient/outpatient selection. Postoperative infection was not a significant complication for appropriately selected patients for outpatient spine surgery. Despite increased hospital care and observation in the inpatient group, infection rates were not statistically different. Obesity seems to be a predictor of readmission with infection.     

Cervical spondylotic myelopathy: National trends in the treatment and peri-operative outcomes over 10 years

BackgroundRecent studies show increases in cervical spine surgery prevalence and cervical spondylotic myelopathy (CSM) diagnoses in the US. However, few studies have examined outcomes for CSM surgical management, particularly on a nationwide scale.ObjectiveEvaluate national trends from 2001 to 2010 for CSM patient surgical approach, postoperative outcomes, and hospital characteristics.MethodsA retrospective nationwide database analysis provided by the Nationwide Inpatient Sample (NIS) including CSM patients aged 25+ who underwent anterior and/or posterior cervical fusion or laminoplasty from 2001 to 2010. Patients with fractures, 9+ levels fused, or any cancer were excluded. Measures included demographics, hospital data, and procedure-related complications. Yearly trends were analyzed using linear regression modeling.Results54,348 discharge cases were identified. ACDF, posterior only, and combined anterior/posterior approach volumes significantly increased from 2001 to 2010 (98.62%, 303.07%, and 576.19%; respectively, p < 0.05). However, laminoplasty volume remained unchanged (p > 0.05). Total charges for ACDF, posterior only, combined anterior/posterior, and laminoplasty approaches all significantly increased (138.72%, 176.74%, 182.48%, and 144.85%, respectively; p < 0.05). For all procedures, overall mortality significantly decreased by 45.34% (p = 0.001) and overall morbidity increased by 33.82% (p = 0.0002). For all procedures except ACDF, which saw a significantly decrease by 8.75% (p < 0.0001), length of hospital stay was unchanged.ConclusionsFor CSM patients between 2001 and 2010, combined surgical approach increased sixfold, posterior only approach increased threefold, and ACDF doubled; laminoplasties without fusion volume remained the same. Mortality decreased whereas morbidity and total charges increased. Length of stay decreased only for ACDF approach. This study provides clinically useful data to direct future research, improving patient outcomes.     

A matched cohort comparison of cervical disc arthroplasty versus anterior cervical discectomy and fusion: Evaluating perioperative outcomes

ObjectiveCervical disc arthroplasty (CDA) is a recent alternative to anterior cervical discectomy and fusion (ACDF) in patients suffering cervical disc herniation and degeneration. To date, a systematic analysis of their comparative advantages and risks following elective surgery remains elusive.MethodsAdult patients undergoing elective CDA or ACDF were extracted from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database years 2011–2014. A total of 19,369 patients were matched 1:1 by age, sex, functional status, charlson comorbidity index, ASA classification, BMI classification, and number of vertebral levels operated on during surgery. This matching process led to a final sample of 588 subjects (294 CDA, 294 ACDF). Multivariable regression was performed for five outcome measures: operation time, early complications, reoperation rates, hospital length of stay (HLOS), and discharge destination. Mean differences (B), odds ratios (OR) and associated 95% confidence intervals (CI) are reported.ResultsCompared to ACDF, CDA was associated with decreased mean operation time (B = −18.78-min, 95% CI [−29.13, −8.42]; p < 0.001), decreased HLOS (B = −0.44-days [−0.77, −0.11]; p = 0.009), and increased likelihood of discharge to home (OR = 5.39 [1.14–25.43]; p = 0.033). No differences in reoperation rates and complications were found.ConclusionIn a matched cohort analysis, CDA performs comparably to ACDF and is associated with decreased operation time and HLOS, and increased likelihood of discharge to home, without differences in 30-day complications or reoperation rates. Future prospective studies are warranted.     

A new zero-profile,stand-alone Fidji cervical cage for the treatment of the single and multilevel cervical degenerative disc disease

To investigate the clinical and radiological results of the new zero-profile, stand-alone Fidji cervical cage to treat single- and multiple-level cervical DDD, and evaluate the safety and efficiency. Between October 2011 and July 2014, 72 consecutive patients (41 males and 31 females; mean age 50.9 years [range, 33–68 years]) with cervical DDD who underwent surgery and were followed for more than 2 years were enrolled in this study (mean 31.1 months, range 24–47 months). The study compared clinical outcomes, radiologic parameters and complication rates. The SF-36, VAS, NDI, and JOA scores of all patients were improved significantly after surgery at any time point. (all p < 0.05). The C2–C7 Cobb angle and the disc height index (DHI) of all patients were improved significantly after surgery at any time point (all p < 0.05). From 3 months after surgery to final follow-up the DHI showed a significant reduction comparing 1 week after surgery (all p < 0.05). The fusion rates were 91.7% (66/72) and the radiologic mean fusion time was 9.9 months. Radiological evidence of adjacent segment degeneration (ASD) was observed in 4/41 patients (9.8%). Postoperative complications included epidural hematoma, hoarseness, dysphagia, axial neck pain, and subsidence. The zero-profile, stand-alone Fidji cervical cage for ACDF can be considered an effective, reliable and safe alternative procedure in the treatment of cervical DDD.     

Clinical experience using polyetheretherketone (PEEK) intervertebral structural cage for anterior cervical corpectomy and fusion

Anterior cervical corpectomy and fusion (ACCF) is commonly performed for various pathologies involving the cervical spine. Although polyetheretherketone (PEEK) cages have been widely used following anterior cervical discectomy and fusion (ACDF), clinical literature demonstrating its efficacy following ACCF is sparse. A retrospective review of patients enrolled in a prospective database who underwent single/multi-level ACCF was performed. Fifty-nine patients were identified who underwent corpectomy reconstruction with PEEK cages for symptomatic degenerative, neoplastic, infectious, or traumatic pathologies of the cervical spine. Thirty-five patients having at least 6 months follow-up (FU) were included in the final analysis. The mean age of patients was 51 years (range, 18–81 years) with FU ranging from 6 to 33 months (mean, 6.6 months). None of the patients had dysphagia at last FU. There was no implant failure with fusion occurring in all patients. While 57% of patients (20/35) remained stable with no progression of myelopathy, 43% (15/35) improved one (11 patients) or two (four patients) Nurick grades after surgery. The use of PEEK cages packed with autograft or allograft is safe and effective following anterior cervical corpectomy, demonstrating high fusion rates and good clinical results. This synthetic material obviates the morbidity associated with autograft harvest and possible infectious risks of allograft. The wide array of cage dimensions facilitates ease of use in patients of all sizes and appears safe for use in the typical pathologic conditions encountered in the cervical spine.     

A meta-analysis of cervical arthroplasty compared to anterior cervical discectomy and fusion for single-level cervical disc disease

There is no consensus on whether anterior cervical arthroplasty or anterior cervical discectomy and fusion (ACDF) is the optimal treatment for single-level cervical radiculopathy or myelopathy. We conducted a meta-analysis of randomized controlled trials to compare the safety and efficacy of anterior cervical arthroplasty with ACDF. Eight studies met the inclusion criteria. Overall, there were significant differences between these two treatment approaches in the arm visual analog scale (VAS) scores [mean difference (MD) = ?4.86, 95% confidence interval (CI) = ?6.42 to ?3.30], neck VAS scores (MD = ?7.90, 95% CI = ?10.36 to ?5.44), overall success rate [odds ratio (OR) = 1.84, 95% CI = 1.43 to 2.36], neurological success rate (OR = 1.75, 95% CI = 1.20 to 2.55), and incidence of reoperation [risk ratio (RR) = 0.50, 95% CI = 0.26 to 0.97]. However, there were no significant differences in the neck disability index (NDI) scores (MD = ?3.81, 95% CI = ?8.12 to 0.51), number of adverse events (RR = 0.77, 95% CI = 0.48 to 1.23), or radiological success rate (OR = 0.87, 95% CI = 0.36 to 2.09). Based on this meta-analysis, cervical arthroplasty is a safe and effective surgical procedure for treating single-level cervical radiculopathy or myelopathy.     

Subsidence after single-level anterior cervical fusion with a stand-alone cage

To investigate the risk factors for subsidence in patients treated with stand-alone anterior cervical discectomy and fusion (ACDF) using polyetheretherketone (PEEK) cages for single-level degenerative cervical disease. Seventy-seven consecutive patients who underwent single-level stand-alone ACDF with a PEEK cage between 2005 and 2012 were included. Subsidence was defined as a decrease in the interbody height of more than 3 mm on radiographs at the 1-year follow-up compared with that in the immediate post-operative image. Patients were divided into the subsidence and non-subsidence groups. The following factors were investigated in relation to the occurrence of subsidence: age, pre-operative overall cervical sagittal angle, segmental angle of the operated level, interbody height, cage height, cage devices and cage location (distance between anterior margin of the body endplate and that of the cage). The clinical outcomes were assessed with visual analog scale, modified Japanese Orthopedic Association score and neck disability index. Twenty-six out of the 77 (33.8%) patients had radiological signs of cage subsidence. Solid fusion was achieved in 25 out of the 26 patients (96.2%) in the subsidence group and in 47 out of the 51 patients (92.2%) in the non-subsidence group. More than 3 mm distance between anterior margin of the vertebral body and that of the cage was significantly associated with subsidence (p < 0.05). However, subsidence did not correlate with fusion rate or clinical outcomes. Cage location was the only significant risk factor. Therefore, cage location should be taken into consideration during stand-alone ACDF using PEEK cages.     

Application of a stand-alone anchored spacer in noncontiguous anterior cervical arthrodesis with radiologic analysis of the intermediate segment

The purpose of this study was to describe the clinical features of noncontiguous cervical degenerative disc disease (cDDD), investigate the efficacy and complications of a stand-alone anchored spacer (SAAS) for patients with noncontiguous cDDD, and present radiologic analysis of the intermediate segment (IS) after skip-level fusion. Nineteen consecutive patients with noncontiguous cDDD who underwent skip-level anterior cervical discectomy and fusion (ACDF) with SAAS from January 2010 to December 2012 were enrolled in this study. Clinical outcomes were assessed preoperatively and at 24 months postoperatively using the Japanese Orthopaedic Association score, Neck Disability Index, and Visual Analog Scale. Overall cervical alignment (OCA) of the cervical spine, and the range of motion (ROM), intervertebral disc height (IDH), disc signal intensity and disc protrusion of IS were measured and compared before and after surgery. Clinical outcomes significantly improved compared to preoperative scores. The OCA was corrected and maintained at 24 months postoperatively compared with preoperative values (p < 0.05). There were no significant differences in the ROM and IDH of the IS at each follow-up (p > 0.05). However, decreased signal intensity on T2-weighted MRI was evidenced in three mobile IS at final follow-up (20.0%). Skip-level ACDF with SAAS may be an efficacious option for the treatment of noncontiguous cDDD.     

Preliminary comparison of radiolucent cages containing either autogenous cancellous bone or hydroxyapatite graft in multilevel cervical fusion

We compared the preliminary outcomes of cervical fusion performed using radiolucent cages containing either cancellous bone or hydroxyapatite graft. From July 2004 to June 2006, 45 consecutive patients presented with a total of 109 levels of degenerative disc disease between the C2 and C7 levels. Each patient underwent anterior cervical discectomy and fusion (ACDF) for each affected cervical disc. The retrospective analysis of the cage fillers was divided into group 1 (23 patients with 56 affected cervical levels) who received cages packed with cancellous bone marrow, and group 2 (22 patients with 53 affected cervical levels) who received cages packed with hydroxyapatite graft. Bone marrow was harvested from the anterior iliac crest. The Prolo scale was used to assess both the economic and functional status postoperatively. The Yates’ correction to test independence in a contingency was used to compare the fusion rate of both groups post-operatively at day 1 and at 1, 3 and 6 month follow-up. At a mean follow-up of 12 months, the fusion rates observed in groups 1 and 2, respectively, were 21.4% and 13.2% after 1 month, 76.8% and 64.2% after 3 months, and 98.2% and 96.2% after 6 months. Functional and economic status were better in group 2, with a statistical significance (p < 0.05) observed at the 3-month follow-up. Although hydroxyapatite graft is an osteoconductive, rather than osteoinductive, material, when used as a cage filler it is a safe and efficient substitute for cancellous bone.     

Duration of electroencephalographic recordings in patients with epilepsy

PurposePrevious studies have demonstrated different diagnostic yields with electroencephalography (EEG). Due to the small sample sizes or different patient populations (outpatients or inpatients only) in these previous studies, the clinical use of routine EEG and outpatient/inpatient video-EEG monitoring (VEM) needs further clarification. In this study, we investigated EEGs obtained from patients referred by epileptologists; by comparing the results of different EEG methods, we sought to determine the optimal durations and specific types of EEG recordings for different clinical situations.MethodsThe data from 335 routine EEGs, 281 3 h outpatient VEMs, and 247 inpatient VEMs (>48 h) were reviewed. We analyzed the latency to the first epileptiform discharge or clinical event.ResultsIn patients undergoing outpatient VEMs, 48% of the first epileptiform discharges appeared within 20 min, and 64% appeared within 30 min. In patients undergoing inpatient VEMs, 21.2% had their first attack within 3 h. The second peak of event occurrence was during the 33rd–36th h. Only 3.5% of the seizures were recorded after 57 h. The detection rate of epileptiform discharges was higher for 3 h outpatient VEM than for routine EEG (54.1% versus 16.4%, p < 0.01). Epileptic and/or nonepileptic events were recorded in 45.8% of the inpatient VEMs, the diagnostic yield of which was higher than for outpatient VEMs (p < 0.01). Since the patients in this study had been selected to limit the bias between each group, the diagnostic yield of EEGs in this study are likely to have been higher than those found in routine practice. Patients with generalized epilepsy had a shorter latency to the first epileptiform discharge compared to patients with localization-related epilepsy (mean, 22.1 min versus 33.9 min, p < 0.05).ConclusionsTwo-thirds of epileptiform discharges were detected within 30 min of VEM. A 30-min recording is recommended for routine EEG examinations that aim to detect epileptiform discharges. A 3 h outpatient VEM is a reasonable option when a routine EEG fails to detect epileptiform discharges. The latency to the first epileptiform discharge was shorter in patients with generalized epilepsy than in patients with localization-related epilepsy. 48 h of inpatient VEM might be adequate for detecting the target events.     

Tantalum trabecular metal implants in anterior cervical corpectomy and fusion: 2-year prospective analysis

Anterior cervical decompression for two or more cervical spondylotic levels can be performed using either multiple anterior cervical discectomies and fusion or anterior cervical corpectomy and fusion (ACCF). A variety of options for ACCF implants exist but to our knowledge, there is no clinical data for the use of tantalum trabecular metal implants (TTMI) for ACCF. A retrospective review was performed of prospectively collected data for ten patients undergoing ACCF with TTMI between 2011 and 2012. Radiological outcome was assessed by measuring the change in cervical (C) lordosis (fusion Cobb and C2–C7 Cobb), graft subsidence (anterior/posterior, determined by the subsidence of anterior/posterior body height of fused segments; cranial/caudal, determined by the cranial/caudal plate-to-disc distances) and rate of fusion using lateral cervical X-rays of patients at 0, 6, 12 and 24 months post-operatively. The Neck Disability Index (NDI) assessed clinical outcome pre-operatively and at 6, 12 and 24 months post-operatively. Cervical lordosis (Cobb angle of fused segment) was 5.2° (± 4.2°) at 0 months and 6.0° (± 5.7°) at 24 months post-operatively. Graft subsidence was observed to occur at 6 months post-operatively and continued throughout follow-up. Anterior, posterior and caudal subsidence occurred more in the first 12 months post-operatively than in the following 12 months (p < 0.05). Average pre-operative NDI was 45%. Average NDIs were 18%, 13% and 10% at 6, 12 and 24 months post-operatively, respectively. ACCF patients treated with TTMI demonstrated stable cervical lordosis over 2 years of follow-up and 100% fusion rates after 2 years. Measures of subsidence appeared to decrease with time. Patients experienced improved clinical outcomes over the 2-year period.     

Unilateral versus bilateral pedicle screw instrumentation for single-level minimally invasive transforaminal lumbar interbody fusion

Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) has become an increasingly popular method of lumbar arthrodesis. However, there are few published studies comparing the clinical outcomes between unilateral and bilateral instrumented MIS TLIF. Sixty-five patients with degenerative lumbar spine disease were enrolled in this study. Thirty-one patients were randomized to the unilateral group and 34 to the bilateral group. Recorded demographic data included sex, age, preoperative diagnosis, and degenerated segment. Operative time, blood loss, hospital stay length, complication rates, and fusion rates were also evaluated. The Oswestry Disability Index (ODI) score and Visual Analog Scale (VAS) pain score data were obtained. All patients were asked to follow-up at 3 and 6 months after surgery, and once every 6 months thereafter. The mean follow-up was 26.6 months (range 18–36 months). The two groups were similar in sex, age, preoperative diagnosis, and operated level. The unilateral group had significantly shorter operative time, lower blood loss, and shorter hospital time than the bilateral group. The average postoperative ODI and VAS scores improved significantly in each group. No significant differences were found between the two groups in relation to ODI and VAS. All patients showed evidence of fusion at 12 months postoperatively. The total fusion rate, screw failure, and general complication rate were not significantly different. Results showed that single-level MIS TLIF with unilateral pedicle screw fixation would be sufficient in the management of preoperatively stable patients with lumbar degenerative disease. It seems that MIS TLIF with unilateral pedicle screw instrumentation is a better choice for single-level degenerative lumbar spine disease.