Minimally invasive transpedicular approach for the treatment of central calcified thoracic disc disease: a technical note.

PURPOSE: To assess the utility of stereotactic navigation for the surgical treatment of ossified, paracentral thoracic discs via a minimally invasive (MI) transpedicular approach. METHODS: The authors performed a retrospective review of cases with paracentral thoracic disc herniation resulting in myelopathy where a traditional MI approach would be difficult, who underwent a stereotactic assisted MI transpedicular approach via a tubular retractor system between 2011 and 2016. Five cases of patients over the age of 18 were selected. Collected data included patient age at surgery, sex, preoperative Nurick grade, number of levels treated, calcified disc presence, length of surgery, estimated blood loss (EBL), length of stay (LOS), complication rate, postoperative Nurick grade, and length of follow-up. RESULTS: Five patients had a stereotaxic assisted MI transpedicular thoracic discectomy for paracentrally located calcified disc herniation. Intraoperative navigational images were acquired using intraoperative CT scans (O-arm) to plan and guide the surgical procedure, and real-time navigation was used for precise navigation around the cord to access and remove all fragments. MIS surgery was successfully performed in these otherwise contraindicated cases due to the use of intraoperative real-time stereotactic navigation. All patients had a successful decompression around the anterior aspect of the cord. CONCLUSION: The traditional MI transpedicular thoracic discectomy approach can be further refined and enhanced by stereotactic navigation to expand the limitations of the MIS technique allowing for an increased number and types of patients eligible for minimally invasive surgery. Therefore, MIS via a tubular retractor system with stereotactic navigation is a novel, safe, and effective improvement in feasibility from the traditional minimally invasive transpedicular thoracic discectomy technique.

Thirty-day readmission and reoperation rates after single-level anterior cervical discectomy and fusion versus those after cervical disc replacement.

OBJECTIVE The goal of this study was to compare 30-day readmission and reoperation rates after single-level anterior cervical discectomy and fusion (ACDF) versus those after cervical disc replacement (CDR). METHODS The authors used the 2013-2014 American College of Surgeons National Surgical Quality Improvement Program database. Included were adult patients who underwent first-time single-level ACDF or CDR for cervical spondylosis or disc herniation. Primary outcome measures were readmission and/or reoperation within 30 days of the original surgery. Logistic regression analysis was used to assess the independent effect of the procedure (ACDF or CDR) on outcome, and results are presented as odds ratios with 95% confidence intervals. RESULTS A total of 6077 patients met the inclusion criteria; 5590 (92.0%) patients underwent single-level ACDF, and 487 (8.0%) patients underwent CDR. The readmission rates were 2.6% for ACDF and 0.4% for CDR (p = 0.003). When stratified according to age groups, only patients between the ages of 41 and 60 years who underwent ACDF had a significantly higher readmission rate than those who underwent CDR (2.5% vs 0.7%, respectively; p = 0.028). After controlling for patient age, sex, body mass index, smoking status, history of chronic obstructive pulmonary disease (COPD), diabetes, hypertension, steroid use, and American Society of Anesthesiologists (ASA) class, patients who underwent CDR were significantly less likely to undergo readmission within 30 days than patients who underwent ACDF (OR 0.23 [95% CI 0.06-0.95]; p = 0.041). Patients with a history of COPD (OR 1.97 [95% CI 1.08-3.57]; p = 0.026) or hypertension (OR 1.62 [95% CI 1.10-2.38]; p = 0.013) and those at ASA Class IV (OR 14.6 [95% CI 1.69-125.75]; p = 0.015) were significantly more likely to require readmission within 30 days. The reoperation rates were 1.2% for ACDF and 0.4% for CDR (p = 0.086), and multivariate analysis revealed that CDR was not associated with lower odds of reoperation (OR 0.60 [95% CI 0.14-2.55]; p = 0.492). However, increasing age was associated with a higher risk (OR 1.02 [95% CI 1.00-1.05]; p = 0.031) of reoperation; a 2% increase in risk per year of age was found. CONCLUSIONS Patients who underwent single-level ACDF had a higher readmission rate than those who underwent single-level CDR in this study. When stratified according to age, this effect was seen only in the 41- to 60-year age group. No significant difference in the 30-day single-level ACDF and single-level CDR reoperation rates was found. Although patients in the ACDF group were older and sicker, other unmeasured covariates might have accounted for the increased rate of readmission in this group, and further investigation is encouraged.

Trends in the Use of Bone Morphogenetic Protein-2 in Adult Spinal Deformity Surgery: A 10-Year Analysis of 54 054 Patients.

BACKGROUND: Bone morphogenetic protein-2 (BMP-2) is an available bone graft option in spinal fusion surgery. The purpose of this study is to investigate the trends of BMP-2 utilization in adult spinal deformity (ASD) surgery. METHODS: The Nationwide Inpatient Sample database from 2002 to 2011 was reviewed. Inclusion criteria were patients over 18 years of age who underwent spinal fusion for ASD. Trends of BMP-2 use were examined over time, as well as stratified based on patient and surgical characteristics. All analyses were done after application of discharge weights to produce national estimates. RESULTS: There were 54 054 patients who met inclusion criteria and were included in this study. The overall rate of BMP-2 use was 39.7% (95% confidence interval 35.0%- 44.3%). Overall, there was steady increase in its use over time, with the highest peak in 2009 (55.3% of all cases used BMP-2), and then a decrease up to 37.9% in 2011 (P < .001). The rate of BMP-2 use was significantly higher for patients older than 54 years of age (compared to patients <54, P < .001). It was also higher in females (P = .009), Caucasian patients (P = .006), and Medicare patients (P = .006). Its use was 28.6% in the Northeast, 38.1% in the South, 45.2% in the Midwest, and 48.2% in the West (P = .035). Circumferential procedures had the highest rate of BMP-2 use (44.3%, P = .045). Average total hospital charges were $152,403 ± 117,454 for patients who did not receive BMP-2 and $205,426 ± 137,561 for patients who did (P < .001). CONCLUSION: After analysis of a large nationwide database, it was found that the rate of BMP-2 use in ASD surgery is approximately 40%. There was a significant increase in use from 2002 to 2009, and a decrease thereafter. The highest rates of use were found in older patients, female patients, white patients, Medicare patients, circumferential approaches, and patients undergoing surgery in the Midwest and West regions.

Ambiguous subdural collection.

Prostate cancer metastasis to the dura is a rare occurrence. Metastasis to the dura can present as signs and symptoms of worsening mental status or neurological deficit. Therefore, malignant metastasis should be considered in a patient presenting with history of prostate cancer and worsening metal status without evidence of trauma.

Volume-Outcome Relationship After 1 and 2 Level Anterior Cervical Discectomy and Fusion.

OBJECTIVE: To investigate the effects of surgeon volume on inpatient morbidity after 1- and 2-level anterior cervical discectomy and fusion (ACDF). METHODS: Data from the Nationwide Inpatient Sample from 2009 were extracted. All adult patients who underwent an elective 1- or 2-level ACDF for degenerative cervical spine disease were identified. Surgeon volume was analyzed as a continuous and categorical variable: very low (<12 procedures per year), low (12-23 procedures per year), medium (24-35 procedures per year), high (36-47 procedures per year), and very high (≥48 procedures per year). A multivariate logistical regression analysis was performed to calculate the adjusted odds ratios of overall in-hospital and surgical complication occurrence in relation to surgeon volume. RESULTS: Eleven thousand two hundred forty-nine admissions were analyzed. The overall complication rate was 4.7%, and the surgical complication rate was 1.2%. Following regression analysis, increasing surgeon volume (evaluated continuously) was independently associated with lower odds of overall complication (odds ratio [OR], 0.99; 95% confidence interval [CI], 0.98-0.99; P < 0.001) and surgical complication development (OR, 0.98; 95% CI, 0.97-0.99; P = 0.004). Surgeons with very high volume (performing 48 or more procedures per year; 4 or more per month) showed a significant decrease in overall complications (OR, 0.58; 95% CI, 0.41-0.84; P = 0.003) and surgical complications (OR, 0.52; 95% CI, 0.25-0.99; P = 0.041) when compared to surgeons with very low volume. CONCLUSION: In this study, increasing surgeon volume was independently associated with significantly lower odds of perioperative complications following 1- and 2-level ACDF. Performing 4 or more procedures per month was associated with the lowest complication rate.

Case-control study of risk factors for surgical site infection after three-column osteotomy for spine deformity.

AIM: To investigate risk factors for surgical site infection (SSI) after three-column osteotomy (3CO) for spinal deformity. MATERIAL AND METHODS: The American College of Surgeons National Surgical Quality Improvement Program database (2012 - 2014) was reviewed. We included adult patients who underwent 3CO and compared pertinent cases (SSI) to controls (no SSI) in terms of preoperative and operative characteristics. Patients with clean/contaminated, contaminated, and dirty/infected wounds were excluded. A stepwise multivariate regression was used to identify independent predictors of SSI, with results presented as odds ratios (OR) with 95% confidence intervals (CI). RESULTS: There were 293 patients who underwent 3CO for spinal deformity, out of whom 15 (5.1%) developed a SSI during the 30-day follow-up period. Of the 15 patients with SSI, 10 underwent reoperation (66.7%) within 30 days. Compared to controls, patients in the SSI group were more likely to be obese (p=0.030), have a higher ASA (American Society of Anesthesiologists physical status) class (p=0.051) and be more likely to undergo multilevel 3CO (p=0.013). After controlling for obesity, bleeding disorder, deformity type, ASA class, preoperative anemia, and multilevel procedures, Class II Obesity (OR 4.98; 95% CI, 1.24 - 19.94; p=0.023) and multilevel 3CO (OR 4.71; 95% CI, 1.30 - 16.94; p=0.018) were significant predictors of SSI occurrence. CONCLUSION: The findings in this study suggest that patients with Class II Obesity and patients who undergo multilevel osteotomy may be at a significantly increased risk of developing a SSI within 30 days after 3CO for spine deformity.

Impact of body mass index on 30-day outcomes after spinopelvic fixation surgery.

BACKGROUND: Obesity is one of the most prevalent chronic diseases associated with degenerative spinal disease. There is limited evidence regarding the short-term outcome of patients with elevated BMI following spinopelvic fixation surgery. METHODS: We used the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database from 2013 to 2014. Inclusion criteria included: adults, aged 18 and older, who underwent all-cause spinopelvic fixation surgery. Primary outcome measures were 30-day readmission, reoperation, and major complication rates. Logistic regression analysis was used to assess the effect of elevated body mass index (BMI) on 30-day outcome. RESULTS: A total of 618 patients met inclusion criteria stratified into levels of BMI: 11.2% were Class 2 obese and 10.3% were Class 3 obese. Significant differences were found between the classes for the incidence of revision surgery, reoperations, and deep wound infections. However, there were no significant increases in readmissions and major complications rates, and only Class 3 obese patients had significantly higher odds of reoperation than those who were not obese. CONCLUSION: Significant differences between all classes of obesity regarding revision surgery, reoperation, and deep wound infection rates were found. Class 3 obese patients had significantly higher odds of reoperation, most likely attributed to the greater number/severity of preoperative comorbidities.

The Impact of Kidney Disease on Acute Tubular Necrosis and Surgical Site Infection After Lumbar Fusion.

BACKGROUND: Kidney disease in spine surgery can be associated with serious complications. OBJECTIVE: To investigate the rate of acute tubular necrosis (ATN) and surgical site infection (SSI) after lumbar fusion in patients with kidney disease. METHODS: A review of the U.S. Nationwide Inpatient Sample from 2002 to 2011 was performed to identify patients who underwent lumbar fusion for degenerative spine disease or disk herniation. Four groups were established: no kidney disease, chronic kidney disease (CKD), end-stage renal disease (ESRD), and posttransplant. A multivariate analysis was performed to control for age, sex, and comorbidities. RESULTS: A total of 268,158 patients met the criteria; 263,757 with no kidney disease (98.4%), 3576 with CKD (1.3%), 586 with ESRD (0.2%), and 239 posttransplant (0.1%). Rates of ATN were 0.1%, 2.9%, 3.6%, and 0.0% for the 4 groups, respectively (P < 0.001). Rates of SSI were 0.3%, 0.4%, 1.0%, and 0.0%, respectively (P = 0.002). After controlling for patient age, sex, and medical comorbidities, patients with CKD (odds ratio [OR], 5.42; 95% confidence interval [CI], 4.14-7.09; P < 0.001) and ESRD (OR, 6.32; 95% CI, 3.89-10.33; P < 0.001) were significantly more likely to develop ATN compared with patients without kidney disease. However, CKD (OR, 0.80; 95% CI, 0.20-3.12; P = 0.754) or ESRD (OR, 1.96; 95% CI, 0.38-10.00; P = 0.415) did not increase the risk for SSI on multivariate analysis. DISCUSSION: The rate of ATN significantly increases based on severity of kidney disease. However, patients with transplants have ATN and SSI rates comparable with patients without kidney disease.

Ultra-delayed lumbar surgical wound hematoma.

BACKGROUND: There exists an inherent risk of increased venous thromboembolism (VTE) in surgical spine patients, which is independent of their existing risk factors. Prophylaxis and treatment of VTE is an imprecise practice and may have serious complications even well after the initial surgery. Furthermore, there are no clear guidelines on how to manage postoperative spine patients with regards to the timing of anticoagulation. CASE DESCRIPTION: Here, we present the case of a middle-aged male, status post L2/3 laminectomy and discectomy who developed bilateral below the knee deep venous thrombosis. He was started on Enoxaparin and transitioned to Warfarin and returned with axial back pain, and was found to have a postoperative hematoma almost 3 weeks later in a delayed fashion. CONCLUSION: Delayed surgical wound hematoma with neural compression is an important complication to identify and should remain high on the differential diagnosis in patients on warfarin who present with axial spinal pain.