Percutaneous Juxtapedicular Cement Salvage of Failed Spinal Instrumentation? Institutional Experience and Cadaveric Biomechanical Study.

BACKGROUND AND OBJECTIVES: Instrumented spinal fusion constructs sometimes fail because of fatigue loading, frequently necessitating open revision surgery. Favorable outcomes after percutaneous juxtapedicular cement salvage (perc-cement salvage) of failing instrumentation have been described; however, this approach is not widely known among spine surgeons , and its biomechanical properties have not been evaluated. We report our institutional experience with perc-cement salvage and investigate the relative biomechanical strength of this technique as compared with 3 other common open revision techniques. METHODS: A retrospective chart review of patients who underwent perc-cement salvage was conducted. Biomechanical characterization of revision techniques was performed in a cadaveric model of critical pedicle screw failure. Three revision cohorts involved removal and replacement of hardware: (1) screw upsizing, (2) vertebroplasty, and (3) fenestrated screw with cement augmentation. These were compared with a cohort with perc-cement salvage performed using a juxtapedicular trajectory with the failed primary screw remaining engaged in the vertebral body. RESULTS: Ten patients underwent perc-cement salvage from 2018 to 2022 to address screw haloing and/or endplate fracture threatening construct integrity. Pain palliation was reported by 8/10 patients. Open revision surgery was required in 4/10 patients, an average of 8.9 months after the salvage procedure (range 6.2-14.7 months). Only one revision was due to progressive hardware dislodgement. The remainder avoided open revision surgery through an average of 1.9 years of follow-up. In the cadaveric study, there were no significant differences in pedicle screw pullout strength among any of the revision cohorts. CONCLUSION: Perc-cement salvage of failing instrumentation is reasonably efficacious. The technique is biomechanically noninferior to other revision strategies that require open surgery for removal and replacement of hardware. Open revision surgery may be avoided by perc-cement salvage in select cases.

Carbon fiber-reinforced PEEK spinal implants for primary and metastatic spine tumors: a systematic review on implant complications and radiotherapy benefits.

OBJECTIVE: By minimizing imaging artifact and particle scatter, carbon fiber-reinforced polyetheretherketone (CF-PEEK) spinal implants are hypothesized to enhance radiotherapy (RT) planning/dosing and improve oncological outcomes. However, robust clinical studies comparing tumor surgery outcomes between CF-PEEK and traditional metallic implants are lacking. In this paper, the authors performed a systematic review of the literature with the aim to describe clinical outcomes in patients with spine tumors who received CF-PEEK implants, focusing on implant-related complications and oncological outcomes. METHODS: A systematic review of the literature published between database inception and May 2022 was performed in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The PubMed database was queried using the terms "carbon fiber" and "spine" or "spinal." The inclusion criteria were articles that described patients with CF-PEEK pedicle screw fixation and had a minimum of 5 patients. Case reports and phantom studies were excluded. RESULTS: This review included 11 articles with 326 patients (237 with CF-PEEK-based implants and 89 with titanium-based implants). The mean follow-up period was 13.5 months, and most tumors were metastatic (67.1%). The rates of implant-related complications in the CF-PEEK and titanium groups were 7.8% and 4.7%, respectively. The rate of pedicle screw fracture was 1.7% in the CF-PEEK group and 2.4% in the titanium group. The rates of reoperation were 5.7% (with 60.0% because of implant failure or junctional kyphosis) and 4.8% (all because of implant failure or junctional kyphosis) in the CF-PEEK and titanium groups, respectively. When reported, 72.5% of patients received postoperative RT (41.0% stereotactic body RT, 30.8% fractionated RT, 25.6% proton, 2.6% carbon ion). Four articles suggested that implant artifact was reduced in the CF-PEEK group. Local recurrence occurred in 14.4% of CF-PEEK and 10.7% of titanium-implanted patients. CONCLUSIONS: While CF-PEEK harbors similar implant failure rates to traditional metallic implants with reduced imaging artifact, it remains unclear whether CF-PEEK implants improve oncological outcomes. This study highlights the need for prospective, direct comparative clinical studies.

Developing an Automated Registry (Autoregistry) of Spine Surgery Using Natural Language Processing and Health System Scale Databases.

BACKGROUND AND OBJECTIVES: Clinical registries are critical for modern surgery and underpin outcomes research, device monitoring, and trial development. However, existing approaches to registry construction are labor-intensive, costly, and prone to manual error. Natural language processing techniques combined with electronic health record (EHR) data sets can theoretically automate the construction and maintenance of registries. Our aim was to automate the generation of a spine surgery registry at an academic medical center using regular expression (regex) classifiers developed by neurosurgeons to combine domain expertise with interpretable algorithms. METHODS: We used a Hadoop data lake consisting of all the information generated by an academic medical center. Using this database and structured query language queries, we retrieved every operative note written in the department of neurosurgery since our transition to EHR. Notes were parsed using regex classifiers and compared with a random subset of 100 manually reviewed notes. RESULTS: A total of 31 502 operative cases were downloaded and processed using regex classifiers. The codebase required 5 days of development, 3 weeks of validation, and less than 1 hour for the software to generate the autoregistry. Regex classifiers had an average accuracy of 98.86% at identifying both spinal procedures and the relevant vertebral levels, and it correctly identified the entire list of defined surgical procedures in 89% of patients. We were able to identify patients who required additional operations within 30 days to monitor outcomes and quality metrics. CONCLUSION: This study demonstrates the feasibility of automatically generating a spine registry using the EHR and an interpretable, customizable natural language processing algorithm which may reduce pitfalls associated with manual registry development and facilitate rapid clinical research.

Radiation Exposure in Posterior Lumbar Fusion: A Comparison of CT Image-Guided Navigation, Robotic Assistance, and Intraoperative Fluoroscopy.

STUDY DESIGN: Retrospective clinical review. OBJECTIVE: To assess the use of intraoperative computed tomography (CT) image-guided navigation (IGN) and robotic assistance in posterior lumbar surgery and their relationship with patient radiation exposure and perioperative outcomes. METHODS: Patients ≥18 years old undergoing 1- to 2-level transforaminal lateral interbody fusion in 12-month period were included. Chart review was performed for pre- and intraoperative data on radiation dose and perioperative outcomes. All radiation doses are quantified in milliGrays (mGy). Univariate analysis and multivariate logistic regression analysis were utilized for categorical variables. One-way analysis of variance with post hoc Tukey test was used for continuous variables. RESULTS: A total of 165 patients were assessed: 12 IGN, 62 robotic, 56 open, 35 fluoroscopically guided minimally invasive surgery (MIS). There was a lower proportion of women in open and MIS groups (P = .010). There were more younger patients in the MIS group (P < .001). MIS group had the lowest mean posterior levels fused (P = .015). Total-procedure radiation, total-procedure radiation/level fused, and intraoperative radiation was the lowest in the open group and highest in the MIS group compared with IGN and robotic groups (all P < .001). Higher proportion of robotic and lower proportion of MIS patients had preoperative CT (P < .001). Estimated blood loss (P = .002) and hospital length of stay (P = .039) were lowest in the MIS group. Highest operative time was observed for IGN patients (P < .001). No differences were observed in body mass index, Charlson Comorbidity Index, and postoperative complications (P = .313, .051, and .644, respectively). CONCLUSION: IGN and robotic assistance in posterior lumbar fusion were associated with higher intraoperative and total-procedure radiation exposure than open cases without IGN/robotics, but significantly less than MIS without IGN/robotics, without differences in perioperative outcomes. Fluoro-MIS procedures reported highest radiation exposure to patient, and of equal concern is that the proportion of total radiation dose also applied to the surgeon and operating room staff in fluoro-MIS group is higher than in IGN/robotics and open groups.

Posterior Dynamic Stabilization of the Lumbar Spine Review of Biomechanical and Clinical Studies.

Fusion and rigid instrumentation have been the mainstay for the surgical treatment of degenerative diseases of the spine for many years. Dynamic stabilization provides a theoretical advantage of decreased biomechanical stress on adjacent spinal segments and decreased fatigue failure of implants. Artificial discs provide an alternative treatment and have been well-studied in the literature. Another technology that is currently used in Europe but rarely in the USA is flexible rods attached to pedicle screws instead of rigid rods or bone fusion. We performed a literature review of the current systems of flexible rod stabilization, while also considering range of motion, loading characteristics, and infection rates.

Intrawound Vancomycin Decreases the Risk of Surgical Site Infection After Posterior Spine Surgery: A Multicenter Analysis.

STUDY DESIGN: Secondary analysis of data from a prospective multicenter observational study. OBJECTIVE: The aim of this study was to evaluate the occurrence of surgical site infection (SSI) in patients with and without intrawound vancomycin application controlling for confounding factors associated with higher SSI after elective spine surgery. SUMMARY OF BACKGROUND DATA: SSI is a morbid and expensive complication associated with spine surgery. The application of intrawound vancomycin is rapidly emerging as a solution to reduce SSI following spine surgery. The impact of intrawound vancomycin has not been systematically studied in a well-designed multicenter study. METHODS: Patients undergoing elective spine surgery over a period of 4 years at seven spine surgery centers across the United States were included in the study. Patients were dichotomized on the basis of whether intrawound vancomycin was applied. Outcomes were occurrence of SSI within postoperative 30 days and SSI that required return to the operating room (OR). Multivariable random-effect log-binomial regression analyses were conducted to determine the relative risk of having an SSI and an SSI with return to OR. RESULTS: .: A total of 2056 patients were included in the analysis. Intrawound vancomycin was utilized in 47% (n = 966) of patients. The prevalence of SSI was higher in patients with no vancomycin use (5.1%) than those with use of intrawound vancomycin (2.2%). The risk of SSI was higher in patients in whom intrawound vancomycin was not used (relative risk (RR) -2.5, P < 0.001), increased number of levels exposed (RR -1.1, P = 0.01), and those admitted postoperatively to intensive care unit (ICU) (RR -2.1, P = 0.005). Patients in whom intrawound vancomycin was not used (RR -5.9, P < 0.001), increased number of levels were exposed (RR-1.1, P = 0.001), and postoperative ICU admission (RR -3.3, P < 0.001) were significant risk factors for SSI requiring a return to the OR. CONCLUSION: The intrawound application of vancomycin after posterior approach spine surgery was associated with a reduced risk of SSI and return to OR associated with SSI. LEVEL OF EVIDENCE: 2.

Early Lessons on Bundled Payment at an Academic Medical Center.

INTRODUCTION: Orthopaedic care is shifting to alternative payment models. We examined whether New York University Langone Medical Center achieved savings under the Centers for Medicare and Medicaid Services Bundled Payments for Care Improvement initiative. METHODS: This study was a difference-in-differences study of Medicare fee-for-service patients hospitalized from April 2011 to June 2012 and October 2013 to December 2014 for lower extremity joint arthroplasty, cardiac valve procedures, or spine surgery (intervention groups), or for congestive heart failure, major bowel procedures, medical peripheral vascular disorders, medical noninfectious orthopaedic care, or stroke (control group). We examined total episode costs and costs by service category. RESULTS: We included 2,940 intervention episodes and 1,474 control episodes. Relative to the trend in the control group, lower extremity joint arthroplasty episodes achieved the greatest savings: adjusted average episode cost during the intervention period decreased by $3,017 (95% confidence interval [CI], -$6,066 to $31). For cardiac procedures, the adjusted average episode cost decreased by $2,999 (95% CI, -$8,103 to $2,105), and for spinal fusion, it increased by $8,291 (95% CI, $2,879 to $13,703). Savings were driven predominantly by shifting postdischarge care from inpatient rehabilitation facilities to home. Spinal fusion index admission costs increased because of changes in surgical technique. DISCUSSION: Under bundled payment, New York University Langone Medical Center decreased total episode costs in patients undergoing lower extremity joint arthroplasty. For patients undergoing cardiac valve procedures, evidence of savings was not as strong, and for patients undergoing spinal fusion, total episode costs increased. For all three conditions, the proportion of patients referred to inpatient rehabilitation facilities upon discharge decreased. These changes were not associated with an increase in index hospital length of stay or readmission rate. CONCLUSION: Opportunities for savings under bundled payment may be greater for lower extremity joint arthroplasty than for other conditions.

Trends in the presentation, surgical treatment, and outcomes of tethered cord syndrome: A nationwide study from 2001 to 2010.

OBJECTIVE: This is a nationwide query into surgical management techniques for tethered cord syndrome, focusing on patient demographic, hospital characteristics, and treatment outcomes. Our hypothesis is that detethering vs. fusion for TCS results in different in-hospital complications. MATERIALS AND METHODS: Retrospective review of the Nationwide Inpatient Sample 2001-2010. Inclusion: TCS discharges undergoing detethering or fusion. Sub-analysis compared TCS cases by age (pediatric [≤9years] vs. adolescent [10-18year]). Independent t-tests identified differences between fusion and detethering for hospital-related and surgical factors; multivariate analysis investigated procedure as a risk factor for complications/mortality. RESULTS: 6457 TCS discharges: 5844 detetherings, 613 fusions. Fusion TCS had higher baseline Deyo Index (0.16 vs. 0.06), procedure-related complications (21.3% vs. 7.63%), and mortality (0.33% vs. 0.09%) than detethering, all p<0.001. Detethering for TCS was a significant factor for reducing mortality (OR 0.195, p<0.001), cardiac (OR 0.27, p<0.001), respiratory (OR 0.26, p<0.001), digestive system (OR 0.32, p<0.001), puncture nerve/vessel (OR 0.56, p=0.009), wound (OR 0.25, p<0.001), infection (OR 0.29, p<0.001), posthemorrhagic anemia (OR 0.04, p=0.002), ARDS (OR 0.13, p<0.001), and venous thrombotic (OR 0.53, p=0.043) complications. Detethering increased nervous system (OR 1.34, p=0.049) and urinary (OR 2.60, p<0.001) complications. Adolescent TCS had higher Deyo score (0.08 vs. 0.03, p<0.001), LOS (5.77 vs. 4.13days, p<0.001), and charges ($54,592.28 vs. $33,043.83, p<0.001), but similar mortality. Adolescent TCS discharges had increased prevalence of all procedure-related complications, and higher overall complication rate (11.10% vs. 5.08%, p<0.001) than pediatric. CONCLUSIONS: With fusion identified as a significant risk factor for mortality and multiple procedure-related complications in TCS surgical patients, this study could aid surgeons in counseling TCS patients to optimize outcomes.

Operative fusion of multilevel cervical spondylotic myelopathy: Impact of patient demographics.

Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in patients older than age 55, with operative management being a widely adopted approach. Previous work has shown that private insurance status, gender and patient race are predictive of the operative approach patients receive (anterior-only, posterior-only, combined anterior-posterior). The Nationwide Inpatient Sample from 2001 to 2010 was used to assess the potential role of multilevel CSM as a contributing factor in determining which operative approach CSM patients receive, as it is rare for an anterior-only approach to be sufficient for CSM patients requiring fusion of four or more involved levels. Multivariate analyses revealed that female sex (OR=3.78; 95% CI=2.08-6.89; p<0.0001), private insurance (OR=5.02; 95% CI=2.26-11.12; p<0.0001), and elective admission type (OR=4.12; 95% CI=1.65-10.32; p=0.0025) were predictive of increased receipt of a 3+ level fusion in CSM. No other variables, including patient age, race, income, or admission source were predictive of either increased or decreased likelihood of receiving fusion of at least three levels for CSM. In conclusion, female sex, private insurance status, and elective admission type are each independent predictors in CSM for receipt of a 3+ level fusion, while patient age, race and income are not. Given the propensity of fusions greater than three levels to require posterior approaches and the association between posterior CSM approaches and increased morbidity/mortality, these findings may prove useful as to which patient demographics are predictive of increased morbidity and mortality in operative treatment of CSM.

Impact of Race and Insurance Status on Surgical Approach for Cervical Spondylotic Myelopathy in the United States: A Population-Based Analysis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of the study was to assess factors potentially impacting the operative approach chosen for cervical spondylotic myelopathy (CSM) patients on a nationwide level. SUMMARY OF BACKGROUND DATA: CSM is one of the most common spinal disorders treated by spine surgeons, with operative management consisting of three approaches: anterior-only, posterior-only, or combined anterior-posterior. It is unknown whether the operative approach used differs based on patient demographics and/or insurance status. METHODS: The nationwide inpatient sample from 2001 to 2010 was used for analysis. Admissions having a diagnosis code of 721.1 and a primary procedure code of 81.02/81.03, 81.32/81.33, 81.02/81.03, or 81.32/81.33 (combined anterior and posterior fusion/refusion at C2 or below), and 3.09 (decompression of the spinal canal including laminoplasty) were included. Analysis was adjusted for several variables including patient age, race, sex, primary payer for care, and admission source/type. RESULTS: Multivariate analyses revealed that non-white race (black [odds ratio, OR = 1.39; 95% confidence interval, CI = 1.32-1.47; P < 0.0001], Hispanic [OR = 1.51; 95% CI = 1.38-1.66; P < 0.0001], Asian/Pacific Islander [OR = 1.40; 95% CI = 1.15-1.70; P = 0.0007], Native American [OR = 1.33; 95% CI = 1.02-1.73; P = 0.037]) and increasing age (OR = 1.03; P < 0.0001) were predictive of receiving posterior-only approaches. Female sex (OR = 1.39; 95% CI = 1.34-1.43; P < 0.0001), private insurance (OR = 1.19; 95% CI = 1.14-1.25; P < 0.0001), and nontrauma center admission type (OR = 1.29-1.39; 95% CI = 1.16-1.56; P < 0.0001) were independently predictive of increased likelihood of receiving an anterior-only approach. Hispanic race (OR = 1.35; 95% CI = 1.14-1.59; P = 0.0004) and admission source (another hospital [OR = 1.65; 95% CI = 1.20-2.27; P = 0.0023], other health facility [OR = 1.68; 95% CI = 1.13-2.51; P = 0.011]) were the only variables predictive of increased combined anterior-posterior approaches; Native American race (OR = 0.32; 95% CI = 0.13-0.78; P = 0.013) decreased the likelihood of a combined anterior-posterior approach. CONCLUSION: Private insurance status, female sex, and white race independently predict receipt of anterior-only CSM approaches, whereasd non-white race (black, hispanic, Asian/Pacific Islander, Native American) and nonprivate insurance predict receiving posterior-only CSM approaches. Given recent literature demonstrating posterior-only approaches as predictive of increased mortality in CSM (Kaye et al, 2015), our findings indicate that for CSM patients, non-white race may significantly increase mortality risk, whereas private insurance status may significantly decrease the risk of mortality. Further prospective study will be needed to more definitively address these issues. LEVEL OF EVIDENCE: 3.

Preoperative Predictors of Spinal Infection within the National Surgical Quality Inpatient Database.

BACKGROUND: Surgical-site infections (SSIs) are a major cause of morbidity and mortality, increasing the length and cost of hospitalization. In patients undergoing spine surgery, there are limited large-scale data on patient-specific risk factors for SSIs. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was reviewed for all spinal operations between 2006 and 2012. The rates of 30-day SSIs were calculated, and univariate analysis of selected preoperative risk factors was performed. Multivariate analysis was then used to identify independent predictors of SSIs. RESULTS: A total of 1110 of the 60,179 patients (1.84%) had a postoperative wound infection. There were 527 (0.87%) deep and 590 (0.98%) superficial infections. Patients with infections had greater rates of sepsis, longer lengths of stay, and more return visits to the operating room. Independent predictors of infection were female sex, inpatient status, insulin-dependent diabetes, preoperative steroid use greater than 10 days, hematocrit less than 35, body mass index greater than 30, wound class, American Society of Anesthesiologists class, and operative duration. CONCLUSIONS: Analysis of a large national patient database revealed many independent risk factors for SSIs after spinal surgery. Some of these risk factors can be modified preoperatively to reduce the risk of postoperative infection.

Predictors of pain and disability outcomes in one thousand, one hundred and eight patients who underwent lumbar discectomy surgery.

BACKGROUND: A key component toward improving surgical outcomes is proper patient selection. Improved selection can occur through exploration of prognostic studies that identify variables which are associated with good or poorer outcomes with a specific intervention, such as lumbar discectomy. To date there are no guidelines identifying key prognostic variables that assist surgeons in proper patient selection for lumbar discectomy. The purpose of this study was to identify baseline characteristics that were related to poor or favourable outcomes for patients who undergo lumbar discectomy. In particular, we were interested in prognostic factors that were unique to those commonly reported in the musculoskeletal literature, regardless of intervention type. METHODS: This retrospective study analysed data from 1,108 patients who underwent lumbar discectomy and had one year outcomes for pain and disability. All patient data was part of a multicentre, multi-national spine repository. Ten relatively commonly captured data variables were used as predictors for the study: (1) age, (2) body mass index, (3) gender, (4) previous back surgery history, (5) baseline disability, unique baseline scores for pain for both (6) low back and (7) leg pain, (8) baseline SF-12 Physical Component Summary (PCS) scores, (9) baseline SF-12 Mental Component Summary (MCS) scores, and (10) leg pain greater than back pain. Univariate and multivariate logistic regression analyses were run against one year outcome variables of pain and disability. RESULTS: For the multivariate analyses associated with the outcome of pain, older patients, those with higher baseline back pain, those with lesser reported disability and higher SF-12 MCS quality of life scores were associated with improved outcomes. For the multivariate analyses associated with the outcome of disability, presence of leg pain greater than back pain and no previous surgery suggested a better outcome. CONCLUSIONS: For this study, several predictive variables were either unique or conflicted with those advocated in general prognostic literature, suggesting they may have value for clinical decision making for lumbar discectomy surgery. In particular, leg pain greater than back pain and older age may yield promising value. Other significant findings such as quality of life scores and prior surgery may yield less value since these findings are similar to those that are considered to be prognostic regardless of intervention type.

Older Age and Leg Pain Are Good Predictors of Pain and Disability Outcomes in 2710 Patients Who Receive Lumbar Fusion.

BACKGROUND: Identifying appropriate candidates for lumbar spine fusion is a challenging and controversial topic. The purpose of this study was to identify baseline characteristics related to poor/favorable outcomes at 1 year for a patient who received lumbar spine fusion. QUESTIONS/PURPOSES: The aims of this study were to describe baseline characteristics of those who received lumbar surgery and to identify baseline characteristics from a spine repository that were related to poor and favorable pain and disability outcomes for patient who received lumbar fusion (with or without decompression), who were followed up for 1 full year and discriminate predictor variables that were either or in contrast to prognostic variables reported in the literature. METHODS: This study analyzed data from 2710 patients who underwent lumbar spine fusion. All patient data was part of a multicenter, multi-national spine repository. Ten relatively commonly captured data variables were used as predictors for the study. Univariate/multivariate logistic regression analyses were run against outcome variables of pain/disability. RESULTS: Multiple univariate findings were associated with pain/disability outcomes at 1 year including age, previous surgical history, baseline disability, baseline pain, baseline quality of life scores, and leg pain greater than back pain. Notably significant multivariate findings for both pain and disability include older age, previous surgical history, and baseline mental summary scores, disability, and pain. CONCLUSION: Leg pain greater than back pain and older age may yield promising value when predicting positive outcomes. Other significant findings may yield less value since these findings are similar to those that are considered to be prognostic regardless of intervention type.

Low-molecular-weight heparin prophylaxis 24 to 36 hours after degenerative spine surgery: risk of hemorrhage and venous thromboembolism.

STUDY DESIGN: Retrospective review. OBJECTIVE: To assess the safety and efficacy of prophylactic low-molecular-weight heparin (LMWH) started 24 to 36 hours after degenerative spine surgery. SUMMARY OF BACKGROUND DATA: Venous thromboembolism (VTE) is a significant postoperative complication best averted with dual mechanical/pharmacological prophylaxis. Pharmacological prophylaxis is widely used in patients with spinal cord injury, but there is no consensus on its role in degenerative spine surgery, particularly after laminectomy with the concurrent risk of epidural hematoma. The literature suggests a small but potentially devastating hemorrhage risk when LMWH is started within 24 hours of spine surgery. An intermediate strategy is delayed LMWH initiation to minimize hemorrhage risk and retain benefits of dual prophylaxis. METHODS: Operative reports of the senior author were retrospectively reviewed for all cases of cervical and lumbar laminectomy from 2007 to 2011. Single-level decompressions without fusion and all nondegenerative cases were excluded. Baseline and operative details were recorded. Mechanical prophylaxis was used throughout admission, and prophylactic LMWH was started postoperative day 1 at 10 PM. All cases of postoperative hemorrhage (epidural hematoma, superficial hematoma, persistent wound drainage), deep venous thrombosis, and pulmonary embolism were noted. RESULTS: A total of 367 patients underwent multilevel laminectomy or laminectomy and fusion for degenerative disease. VTE risk factors (age >60 yr, smoking, obesity) were common. No patients receiving LMWH 24 to 36 hours after surgery developed postoperative hemorrhage (95% confidence interval: 0-0.8%). Nearly half of the study population underwent lower extremity ultrasonography or chest computed tomography, and acute VTE was diagnosed in 14 patients (3.8%; 95% confidence interval: 2.1-6.3). CONCLUSION: LMWH prophylaxis seems to carry a very low hemorrhage risk when started 24 to 36 hours after spine surgery. Larger, prospective studies are needed to assess the safety of early delayed LMWH administration more definitively. Even with aggressive prophylaxis, patients undergoing fusion or multilevel laminectomy for degenerative disease are at significant risk for VTE.

Lumbar laminectomy and fusion with routine local application of vancomycin powder: decreased infection rate in instrumented and non-instrumented cases.

OBJECTIVE: Wound infections are one of the most common and potentially devastating complications of spinal surgery. Intra-wound application of vancomycin powder has been shown to lower the infection risk following posterior instrumented fusion, but little evidence supports use in other spinal operations. The goal of this study is to assess the efficacy of vancomycin powder for lumbar laminectomy and fusion, both instrumented and non-instrumented. METHODS: All cases of lumbar laminectomy and posterior fusion (with or without pedicle screw fixation) by a single surgeon were reviewed from 2007 to 2011. Routine application of 1g vancomycin powder was started in August 2009. Baseline characteristics and operative data were compared between untreated patients and those who received vancomycin powder. Rates of wound infection were compared for all fusions, and then separately for instrumented and non-instrumented cases. RESULTS: 253 patients underwent lumbar laminectomy and fusion between 2007 and 2011. Baseline and operative variables were similar between untreated patients (n=97) and those who received vancomycin powder (n=156). Patients were followed for at least one year. The infection rate fell significantly following introduction of vancomycin powder (from 11% to 0%, p=0.000018). Subgroup analysis revealed significant infection reduction for both instrumented cases (from 12% to 0%, p=0.000806) and non-instrumented cases (from 10% to 0%, p=0.0496). No complications attributable to vancomycin powder were identified. CONCLUSION: Local vancomycin powder appears to lower the risk of wound infection following lumbar laminectomy and fusion, both instrumented and non-instrumented. Further studies are needed to optimize dosing of vancomycin powder, assess long-term safety and efficacy, and evaluate use in other spinal operations.

Decreased risk of wound infection after posterior cervical fusion with routine local application of vancomycin powder.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: To assess the ability of local vancomycin powder to prevent wound infection after posterior cervical fusion. SUMMARY OF BACKGROUND DATA: Wound infections are a significant source of morbidity and cost associated with spine surgery. Intraoperative application of vancomycin powder to the wound edges has been shown to lower the infection risk after posterior instrumented thoracolumbar fusion. There is little data on the efficacy and safety of local vancomycin powder in cervical spine surgery. METHODS: All cases of posterior cervical fusion by a single surgeon were reviewed from 2007 to 2011. Routine application of 1 gram of vancomycin powder was started in August 2009. Baseline characteristics, operative details, and rates of wound infection and pseudarthrosis were compared between untreated patients and those who received vancomycin powder. RESULTS: A total 171 patients underwent posterior cervical fusion between 2007 and 2011. Baseline and operative variables were similar between untreated patients (n = 92) and those who received vancomycin powder (n = 79). Patients were followed for a minimum of 1 year (range, 1.1-5.7 yr). The infection rate fell from 10.9% to 2.5% (P = 0.0384) following the introduction of vancomycin powder. The untreated and treated groups had similar rates of pseudarthrosis (5.4% vs. 5.1%). No complications attributable to vancomycin powder were identified. CONCLUSION: Routine local application of vancomycin powder is a low-cost effective strategy for preventing wound infection after posterior cervical fusion. Further studies are needed to optimize dosing, assess long-term safety, and evaluate use in other spinal operations. LEVEL OF EVIDENCE: 2.

Metameric thoracic lesion: report of a rare case and a guide to management.

Metameric lesions of the spine are rare. The authors present a case of patient with a complex metameric vascular lesion of the thoracic spine and describe a management strategy for this entity.

Large cell neuroendocrine carcinoma of the lung metastatic to the cauda equina.

BACKGROUND CONTEXT: Large cell neuroendocrine carcinoma of the lung is an aggressive tumor with unique histopathological features. It is not known to metastasize to the spine. PURPOSE: To report a metastatic case of this rare tumor to the cauda equina. STUDY DESIGN: Case report. METHODS: Retrospective case review and review of the literature. RESULTS: The authors report a rare case of a large cell neuroendocrine lung metastasis to the lumbar spine, causing right foot drop. Magnetic resonance imaging revealed a heterogeneously enhancing intradural extramedullary mass at L2/L3 level compressing the surrounding nerve roots. During surgery, the identified nerve roots were encased by the tumor, and the dissection was tedious. Postoperatively, the patient reported significantly improved back pain and he had severe foot weakness. The functional outcome was poor because the patient lost entirely his foot function; however, his back pain improved significantly after surgery. CONCLUSIONS: This is the first published study in which the authors described a metastasis of a rather uncommon lung cancer to the cauda equina. When a lesion of the cauda equina presents with a rapid progressive neurological deficit, leptomeningeal metastasis should be in the differential diagnosis.

Minimally invasive atlantoaxial fusion.

BACKGROUND: C1-C2 fusion has significantly advanced from predominantly wiring/cable modalities to more biomechanically stable screw-rod techniques. Minimally invasive surgical techniques represents the most recent modification of atlantoaxial fixation. The indications, rationale, and surgical technique of this novel procedure are described. METHODS: Six patients requiring C1-C2 fusion (5 type II odontoid fractures and 1 os odontoideum) underwent minimally invasive C1-C2 fusion over a 2-year period. The cohort consisted of 5 men and 1 woman with a mean age of 51 years (age range, 39-64 y). All 6 patients underwent bilateral segmental atlantoaxial fixation using an expandable tubular retractor. RESULTS: The mean follow-up time was 32 months (age range, 24-46 mo) There were no intraoperative complications, and the mean estimated blood loss was 100 mL. Solid fusion was achieved in all 6 patients, without pathological motion on dynamic studies. Postoperative computed tomographic images showed no hardware malposition in the scanned patients (4 of the 6 patients). CONCLUSIONS: Placement of C1 and C2 instrumentation using minimally invasive techniques is technically feasible. Because the instrumentation and the means of obtaining arthrodesis do not differ substantively from the standard approach, we would not anticipate long-term results to be different from those of an open procedure, apart from the approach-related morbidity.