Factors Related to Clinical Performance in Spine Surgery Fellowship: Can We Predict Success.

INTRODUCTION: The factors most important in the spine fellowship match may not ultimately correlate with quality of performance during fellowship. This study examined the spine fellow applicant metrics correlated with high application rank compared with the metrics associated with the strongest clinical performance during fellowship. METHODS: Spine fellow applications at three academic institutions were retrieved from the San Francisco Match database (first available to 2021) and deidentified for application review. Application metrics pertaining to research, academics, education, extracurriculars, leadership, examinations, career interests, and letter of recommendations were extracted. Attending spine surgeons involved in spine fellow selection at their institutions were sent a survey to rank (1) fellow applicants based on their perceived candidacy and (2) the strength of performance of their previous fellows. Pearson correlation assessed the associations of application metrics with theoretical fellow rank and actual performance. RESULTS: A total of 37 spine fellow applications were included (Institution A: 15, Institution B: 12, Institution C: 10), rated by 14 spine surgeons (Institution A: 6, Institution B: 4, Institution C: 4). Theoretical fellow rank demonstrated a moderate positive association with overall research, residency program rank, recommendation writer H-index, US Medical Licensing Examination (USMLE) scores, and journal reviewer positions. Actual fellow performance demonstrated a moderate positive association with residency program rank, recommendation writer H-index, USMLE scores, and journal reviewer positions. Linear regressions identified journal reviewer positions (ß = 1.73, P = 0.002), Step 1 (ß = 0.09, P = 0.010) and Step 3 (ß = 0.10, P = 0.002) scores, recommendation writer H-index (ß = 0.06, P = 0.029, and ß = 0.07, P = 0.006), and overall research (ß = 0.01, P = 0.005) as predictors of theoretical rank. Recommendation writer H-index (ß = 0.21, P = 0.030) and Alpha Omega Alpha achievement (ß = 6.88, P = 0.021) predicted actual performance. CONCLUSION: Residency program reputation, USMLE scores, and a recommendation from an established spine surgeon were important in application review and performance during fellowship. Research productivity, although important during application review, was not predictive of fellow performance. LEVEL OF EVIDENCE: III. STUDY DESIGN: Cohort Study.

MRI Vertebral Bone Quality Correlates With Interbody Cage Subsidence After Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective observational study of consecutive patients. OBJECTIVE: The purpose of the study was to evaluate VBQ as a predictor of interbody subsidence and to determine threshold values that portend increased risk of subsidence. SUMMARY OF BACKGROUND DATA: Many risk factors have been reported for the subsidence of interbody cages in anterior cervical discectomy and fusion (ACDF). MRI Vertebral Bone Quality (VQB) is a relatively new radiographic parameter that can be easily obtained from preoperative MRI and has been shown to correlate with measurements of bone density such as DXA and CT Hounsfield Units. METHODS: All patients who underwent 1- to 3-level ACDF using titanium interbodies with anterior plating between the years 2018 and 2020 at our tertiary referral center were included. Subsidence measurements were performed by 2 independent reviewers on CT scans obtained 6 months postoperatively. VBQ was measured on pre-operative sagittal T1 MRI by 2 independent reviewers, and values were averaged. RESULTS: Eight-five fusion levels in 44 patients were included in the study. There were 32 levels (38%) with moderate subsidence and 12 levels with severe subsidence (14%). The average VBQ score in those patients with severe subsidence was significantly higher than those without subsidence (3.80 vs. 2.40, P<0.01). A threshold value of 3.2 was determined to be optimal for predicting subsidence (AUC=0.99) and had a sensitivity of 100% and a specificity of 94.1% in predicting subsidence. CONCLUSIONS: VBQ strongly correlates with the subsidence of interbody grafts after ACDF. A threshold VBQ score value of 3.2 has excellent sensitivity and specificity for predicting subsidence. Spine surgeons can use VBQ as a readily available screening tool to identify patients at higher risk for subsidence. LEVEL OF EVIDENCE: Level-IV.

Does Intrawound Vancomycin Decrease Postoperative Surgical Site Infection in Spine Surgery: A Retrospective Case-control Study.

STUDY DESIGN: Retrospective Case-Control series. OBJECTIVE: The objective of this study is to define the overall postoperative rate of surgical site infection (SSI) in patients undergoing spine surgery and examine the effects of intrawound Vancomycin on postoperative infection rates. SUMMARY OF BACKGROUND DATA: Surgical site infections (SSI) account for 22% of all health care-associated infections. The use of intrawound Vancomycin in an attempt to reduce the incidence of postoperative SSI has not been sufficiently evaluated in the existing literature. METHODS: All spine surgeries (n=19,081) from our institution were reviewed from 2003 to 2013. All cases of verified SSI were identified from the database. Cases were then matched to controls in a 1:1 fashion based on age, gender, and date of surgery (+/-30 d). Patient demographics, comorbidities, estimated blood loss, duration of surgery, intrawound administration of Vancomycin, and smoking status were evaluated. RESULTS: At total of 316 cases of SSI after spine surgery were identified, representing an infection rate of 1.7%. The mean follow-up for cases and controls was 31.5 and 41.6 months, respectively. OR for intrawound Vancomycin was 0.44 (95% CI 0.23-0.88, P =0.019). OR for BMI greater than 30 was 1.63 (95% CI 1.04-2.56, P =0.03). CONCLUSIONS: In this large cohort of spine surgery patients, administration of intrawound Vancomycin was associated with a significant reduction in postoperative surgical site infections. Further studies are needed to determine appropriate dosing and application as well as long-term safety in spine surgery.

Intraoperative Surgeon Assessment of Bone: Correlation to Bone Mineral Density, CT Hounsfield units and Vertebral Bone Quality.

STUDY DESIGN: Retrospective observational study of consecutive patients. OBJECTIVE: The purpose of the study is to determine if a surgeon's qualitative assessment of bone intraoperatively correlates with radiologic parameters of bone strength. SUMMARY OF BACKGROUND DATA: Preoperative radiologic assessment of bone can include modalities such as CT Hounsfield Units (HUs), dual-energy x-ray absorptiometry bone mineral density (DXA BMD) with trabecular bone score (TBS) and MRI vertebral bone quality (VBQ). Quantitative analysis of bone with screw insertional torque and pull-out strength measurement has been performed in cadaveric models and has been correlated to these radiologic parameters. However, these quantitative measurements are not routinely available for use in surgery. Surgeons anecdotally judge bone strength, but the fidelity of the intraoperative judgement has not been investigated. METHODS: All adult patients undergoing instrumented posterior thoracolumbar spine fusion by one of seven surgeons at a single center over a 3-month period were included. Surgeons evaluated the strength of bone based on intraoperative feedback and graded each patient's bone on a 5-point Likert scale. Two independent reviewers measured preoperative CT HUs and MRI VBQ. BMD, lowest T-score and TBS were extracted from DXA within 2 years of surgery. RESULTS: Eighty-nine patients were enrolled and 16, 28, 31, 13 and 1 patients had Likert grade 1 (strongest bone), 2, 3, 4, and 5 (weakest bone), respectively. The surgeon assessment of bone correlated with VBQ (τ=0.15, P=0.07), CT HU (τ=-0.31, P<0.01), lowest DXA T-score (τ=-0.47, P<0.01), and TBS (τ=-0.23, P=0.06). CONCLUSION: Spine surgeons' qualitative intraoperative assessment of bone correlates with preoperative radiologic parameters, particularly in posterior thoracolumbar surgeries. This information is valuable to surgeons as this supports the idea that decisions based on feel in surgery have statistical foundation.

Defeating the Hidden Foe: Antibiotic Therapy and Clinical Outcomes of Cutibacterium acnes Spinal Implant Infections.

Background: Cutibacterium acnes can cause spinal implant infections. However, little is known about the optimal medical management and outcomes of C. acnes spinal implant infections (CSII). Our study aims to describe the management of patients with CSII and evaluate the clinical outcomes. Methods: We performed a retrospective cohort study of patients aged 18 years or older who underwent spinal fusion surgery with instrumentation between January 1, 2011, and December 31, 2020, and whose intraoperative cultures were positive for C. acnes. The primary outcome was treatment failure based on subsequent recurrence, infection with another organism, or unplanned surgery secondary to infection. Results: There were 55 patients with a median follow-up (interquartile range) of 2 (1.2-2.0) years. Overall, there were 6 treatment failures over 85.8 total person-years, for an annual rate of 7.0% (95% CI, 2.6%-15.2%). Systemic antibiotic treatment was given to 74.5% (n = 41) of patients for a median duration of 352 days. In the subgroup treated with systemic antibiotics, there were 4 treatment failures (annual rate, 6.3%; 95% CI, 1.7%-16.2%), all of which occurred while on antibiotic therapy. Two failures occurred in the subgroup without antibiotic treatment (annual rate, 8.8%; 95% CI, 1.1%-31.8%). Conclusions: Our study found that the estimated annual treatment failure rate was slightly higher among patients who did not receive antibiotics. Of the 6 failures observed, 4 had recurrence of C. acnes either on initial or subsequent treatment failures. More studies are warranted to determine the optimal duration of therapy for CSII.

Utility of disc space aspirate cell counts and differentials in the diagnosis of native vertebral osteomyelitis.

Background: Aspiration of intervertebral disc space is often done to confirm the diagnosis of native vertebral osteomyelitis. A study has not been done examining the utility of cell counts and differentials of the aspirated fluid in diagnosing native vertebral osteomyelitis (NVO). Methods: In this feasibility study, we prospectively enrolled patients with a suspected diagnosis of NVO referred to the Division of Neuroradiology for image-guided needle aspiration of the intervertebral disc. In this study, manual cell count was done on the aspirated fluid, followed by a differential cytospin technique and touch prep. We obtained demographic, lab, and microbiologic data and used the receiver operating curve (ROC) for statistical analysis. Results: Over 12 months, we performed 17 aspirates on 14 patients. The median age was 70.5 years (range: 45-77). The median manual cell count on the aspirated fluid was 52 cells  µ L - 1 (range: 0-6656), the median neutrophil percentage on the touch prep slide was 73 % (range: 5 %-100 %), and the median neutrophil percentage on the cytospin slide was 82 % (range: 0 %-100 %). Routine bacterial cultures were positive in five cases, and the 16S ribosomal RNA gene polymerase chain reaction was positive in two cases. The optimal cutoff for a cell count of 104 total nucleated cells offered a sensitivity and specificity of 86 %, and a neutrophil cutoff of 83 % was associated with a 71 % sensitivity and specificity. Conclusion: An image-guided aspirated specimen leukocyte differential of ≥ 83  % neutrophils or a leukocyte count of ≥ 104   µ L - 1 was a sensitive and specific test for diagnosing patients with suspected NVO. Additionally, more extensive studies are warranted to confirm the findings.

Sacral Insufficiency Fracture Following Short-Segment Lumbosacral Fusion: Case Series and Review of the Literature.

STUDY DESIGN: Retrospective case series. OBJECTIVE: Sacral insufficiency fracture is a rare and serious complication following lumbar spine instrumented fusion. The purpose of this study was to describe the patient characteristics, presentation, evaluation, treatment options, and outcomes for patients with sacral insufficiency fracture after short-segment lumbosacral fusion. METHODS: Six patients from our institutional database and 16 patients from literature review were identified with a sacral insufficiency fracture after short-segment (L4-S1 or L5-S1) lumbar fusion within 1 year of surgery. RESULTS: Patients were 55% female with a mean age of 58 years and body mass index of 30 kg/m2. Osteoporosis or osteopenia was the most common comorbidity (85%). Half of patients sustained a sacral fracture after surgery from a posterior approach, while the others had anterior or anterior-posterior surgery. Mean time to fracture was 42 days with patients clinically presenting with new sacral pain (86%), radiculopathy (60%), or neurologic deficit (5%). Ultimately, 73% of patients underwent operative fixation often involving extension of the construct (75%) and fusion to the pelvis (69%). Men (P = .02) and patients with new radicular pain or neurologic deficit (P = .01) were more likely to undergo revision surgical treatment while women over 50 years of age were more likely to be treated conservatively (P = .003). CONCLUSIONS: Spine surgeons should monitor for sacral insufficiency fracture as a source of new-onset pain in the postoperative period in patients with a short segment fusion to the sacrum. The recognition of this complication should prompt an assessment of bone health and management of underlying bone fragility.

The System Is Broken: A Qualitative Assessment of Opioid Prescribing Practices After Spine Surgery.

OBJECTIVE: To elucidate factors that influence opioid prescribing behaviors of key stakeholders after major spine surgery, with a focus on barriers to optimized prescribing. METHODS: In-person semi-structured interviews were performed with 20 surgical and medical professionals (January 23, 2019 to June 11, 2019) at a large academic medical center, including resident physicians, midlevel providers, attending physicians, and clinical pharmacists. Interviews centered on perceptions of postoperative prescribing practices were coded and analyzed using a qualitative inductive approach. RESULTS: Several unique themes emerged. First, wide interprovider variation exists in the perceived role of opioid prescribing guidelines. Second, there are important relationships between clinical experience, time constraints, and postoperative opioid prescribing. Third, opioid tapering is a major area of inconsistency. Fourth, there are serious challenges in managing analgesic expectations, particularly in those with chronic pain. Finally, there is currently no process to facilitate the hand-off or transition of opioid prescribing responsibility between surgical and primary care teams, which represents a major area for practice optimization efforts. CONCLUSION: Despite increased focus on postoperative opioid prescribing, there remain numerous areas for improvement. The development of tools and processes to address critical gaps in postoperative prescribing will be essential for our efforts to reduce long-term opioid use after major spine surgery and improve patient care.

Association Between Spine Surgery and Availability of Opioid Medication.

Importance: Prolonged prescribing of opioids after spine surgery is often perceived as a negative outcome, but successful opioid reduction may occur despite continued prescribing. Improved characterization of opioid availability before and after surgery is necessary to identify these successes. Objective: To evaluate the association between spine surgery and modification of opioid availability postoperatively by using consistent definitions to classify opioid availability before and after surgery. Design, Setting, and Participants: This population-based cohort study included 2223 adults (age ≥18 years) who underwent spine surgery in Olmsted County, Minnesota, from January 1, 2005, through December 31, 2016. Data were analyzed from April 1, 2019, to December 1, 2019. Exposures: Preoperative opioid availability based on prescription data in the 180 days before surgery in accordance with Consortium to Study Opioid Risks and Trends (CONSORT) definitions. Main Outcomes and Measures: Successful modification of opioid availability, defined as an improvement in CONSORT status postoperatively (assessed from 181 to 365 days after surgery) compared with preoperative status, or continued absence of opioid availability for patients with no preoperative availability. Multivariable logistic regression was used to assess the association between preoperative opioid availability and successful modification by 1 year after undergoing surgery. Results: Of 2223 patients included in the study, 1214 were male (54.6%), with a median age of 55 years (interquartile range, 43-68) years. Patients were classified as having no (778 [35.0%]), short-term (1118 [50.3%]), episodic (227 [10.2%]), or long-term (100 [4.5%]) preoperative opioid availability. Of the 2148 patients (96.6%) who were alive at 1 year, postoperative opioid availability was classified as no (1583 [73.7%]), short-term (398 [18.5%]), episodic (104 [4.8%]), and long-term (63 [2.9%]). A total of 1672 patients (77.8%) had successful modification of opioid availability, with success of 83.0% for those with no preoperative availability, 74.9% for those with short-term preoperative availability, 79.8% for those with episodic preoperative availability, and 64.4% for those with long-term preoperative opioid availability. In multivariable analysis, success was significantly associated with preoperative opioid availability (odds ratio [OR] for short term, 0.61 [95% CI, 0.48-0.77]; OR for episodic, 0.95 [95% CI, 0.64-1.40]; OR long term, 0.49 [95% CI, 0.30-0.82]; P < .001 overall vs no availability). Conclusions and Relevance: In this study, when following standardized CONSORT definitions, 4 of 5 adults undergoing spine surgery in a population-based cohort met the criteria for a successful pattern of postoperative opioid prescribing. Similar methods to objectively assess changes in opioid prescribing may be clinically useful in other perioperative settings.

An Objective and Reliable Method for Identifying Sarcopenia in Lumbar Spine Surgery Patients: Using Morphometric Measurements on Computed Tomography Imaging.

STUDY DESIGN: A retrospective observational study. PURPOSE: Establish a quantifiable and reproducible measure of sarcopenia in patients undergoing lumbar spine surgery based on morphometric measurements from readily available preoperative computed tomography (CT) imaging. OVERVIEW OF LITERATURE: Sarcopenia-the loss of skeletal muscle mass-has been linked with poor outcomes in several surgical disciplines; however, a reliable and quantifiable measure of sarcopenia for future assessment of outcomes in spinal surgery patients has not been established. METHODS: A cohort of 90 lumbar spine fusion patients were compared with 295 young, healthy patients obtained from a trauma da¬tabase. Cross-sectional vertebral body (VB) area, as well as the areas of the psoas and paravertebral muscles at mid-point of pedicles at L3 and L4 for both cohorts, was measured using axial CT imaging. Total muscle area-to-VB area ratio was calculated along with intraclass correlation coefficients for interobserver and intraobserver reliability. Finally, T-scores were calculated to help identify those patients with considerably diminished muscle-to-VB area ratios. RESULTS: Both muscle mass and VB areas were considerably larger in males compared with those in females, and the ratio of these two measures was not enough to account for large differences. Thus, a gender-based comparison was made between spine patients and healthy control patients to establish T-scores that would help identify those patients with sarcopenia. The ratio for paravertebral muscle area-to-VB area at the L4 level was the only measure with good interobserver reliability, whereas the other three of the four ratios were moderate. All measurements had excellent correlations for intraobserver reliability. CONCLUSIONS: We postulate that a patient with a T-score <-1 for total paravertebral muscle area-to-VB area ratio at the L4 level is the most reliable method of all our measurements that can be used to diagnose a patient undergoing lumbar spine surgery with sarcopenia.

Implant Sonication versus Tissue Culture for the Diagnosis of Spinal Implant Infection.

MINI: We compared the sensitivity and specificity of peri-implant tissue culture to the vortexing-sonication technique for the diagnosis of spinal implant infection (SII). Lower thresholds of sonicate fluid culture positivity showed increased sensitivity with maintained specificity. We recommend a threshold of 20 CFU/10 mL for sonicate culture positivity for the diagnosis of SII. STUDY DESIGN: This is a retrospective study comparing the diagnosis of spinal implant infection (SII) by peri-implant tissue culture to vortexing-sonication of retrieved spinal implants. OBJECTIVE: We hypothesized that vortexing-sonication would be more sensitive than peri-implant tissue culture. SUMMARY OF BACKGROUND DATA: We previously showed implant vortexing-sonication followed by culture to be more sensitive than standard peri-implant tissue culture for diagnosing of SII. In this follow-up study, we analyzed the largest sample size available in the literature to compare these two culture methods and evaluated thresholds for positivity for sonicate fluid for SII diagnosis. METHODS: We compared peri-implant tissue culture to the vortexing-sonication technique which samples bacterial biofilm on the surface of retrieved spinal implants. We evaluated different thresholds for sonicate fluid positivity and assessed the sensitivity and specificity of the two culture methods for the diagnosis of SII. RESULTS: A total of 152 patients were studied. With more than 100 colony forming units (CFU)/10 mL as a threshold for sonicate fluid culture positivity, there were 46 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 65.2% and 79.6%; the specificities were 88.7% and 93.4%, respectively. With more than 50 CFU/10 mL as a threshold, there were 50 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 68.0% and 76.0%; the specificities were 92.2% for both methods. Finally, with more than or equal to 20 CFU/10 mL as a threshold, there were 52 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 69.2% and 82.7%; the specificities were 94.0% and 92.0%, respectively. CONCLUSION: Implant sonication followed by culture is a sensitive and specific method for the diagnosis of SII. Lower thresholds for defining sonicate fluid culture positivity allow for increased sensitivity with a minimal decrease in specificity, enhancing the clinical utility of implant sonication. LEVEL OF EVIDENCE: 4.

This is a retrospective study comparing the diagnosis of spinal implant infection (SII) by peri-implant tissue culture to vortexing­sonication of retrieved spinal implants. We hypothesized that vortexing­sonication would be more sensitive than peri-implant tissue culture. We previously showed implant vortexing­sonication followed by culture to be more sensitive than standard peri-implant tissue culture for diagnosing of SII. In this follow-up study, we analyzed the largest sample size available in the literature to compare these two culture methods and evaluated thresholds for positivity for sonicate fluid for SII diagnosis. We compared peri-implant tissue culture to the vortexing­sonication technique which samples bacterial biofilm on the surface of retrieved spinal implants. We evaluated different thresholds for sonicate fluid positivity and assessed the sensitivity and specificity of the two culture methods for the diagnosis of SII. A total of 152 patients were studied. With more than 100 colony forming units (CFU)/10 mL as a threshold for sonicate fluid culture positivity, there were 46 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 65.2% and 79.6%; the specificities were 88.7% and 93.4%, respectively. With more than 50 CFU/10 mL as a threshold, there were 50 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 68.0% and 76.0%; the specificities were 92.2% for both methods. Finally, with more than or equal to 20 CFU/10 mL as a threshold, there were 52 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 69.2% and 82.7%; the specificities were 94.0% and 92.0%, respectively. Implant sonication followed by culture is a sensitive and specific method for the diagnosis of SII. Lower thresholds for defining sonicate fluid culture positivity allow for increased sensitivity with a minimal decrease in specificity, enhancing the clinical utility of implant sonication. Level of Evidence: 4.

Low-Pressure Lumbar Provocation Discography According to Spine Intervention Society/International Association for the Study of Pain Standards Does Not Cause Acceleration of Disc Degeneration in Patients With Symptomatic Low Back Pain: A 7-Year Matched Cohort Study.

STUDY DESIGN: Retrospective matched cohort study. OBJECTIVE: To determine if low-pressure lumbar provocation discography (PD) results in long-term accelerated disc degeneration, internal disc disruption, or disc herniation in patients with symptomatic low back pain (LBP). SUMMARY OF BACKGROUND DATA: Study of subjects without clinically-significant LBP suggests that high-pressure PD may accelerate disc degeneration. METHODS: Consecutive patients with symptomatic LBP who underwent magnetic resonance imaging (MRI), PD, and repeat MRI more than 7 years later, but did not undergo subsequent spinal fusion surgery, were included. Punctured discs were matched (1:2 to 1:4) to corresponding discs in a control cohort by age, BMI, Pfirrmann score (±2), and presence of disc herniation; control cohort inclusion required MRIs for symptomatic LBP, separated by more than 7 years. The primary outcome of the study was a progression in Pfirrmann score category (I-II, III-IV, V). MRI disc-to-CSF T2 signal-intensity ratio, disc height, disc herniations, high intensity zones (HIZs), and Modic changes were assessed. RESULTS: Baseline and follow-up MRIs were available for 77 discs exposed to PD, and for 260 discs in the matched control cohort. There was no difference in the proportion of punctured discs that advanced in Pfirrmann score category in the PD group (17%, 95% CI 9-27%) compared with corresponding discs in the Control group (21%, 95% CI 17-27%), P = 0.3578, or in non-punctured discs in the PD group (35%, 95% CI 21-51%) compared with corresponding discs in the Control group (34%, 95% CI 27-42%), P = 0.1169. There were no differences in disc-to-CSF T2 signal-intensity ratio, presence of disc herniations, HIZs, or Modic changes following puncture in the PD versus matched cohort discs or in the non-punctured PD cohort discs versus corresponding control cohort discs (P > 0.05). CONCLUSION: Patients with symptomatic LBP who underwent low-pressure PD, but who did not undergo a subsequent spinal fusion surgery, developed disc degeneration and new disc herniations at a similar rate to corresponding discs in matched control patients. LEVEL OF EVIDENCE: 3.

Tranexamic Acid in Thoracic and Lumbar Fusions and Perioperative Blood Loss.

STUDY DESIGN: This study was a retrospective cohort design. OBJECTIVE: The objective of this study was to examine the impact of tranexamic acid (TXA) on total perioperative wound output following thoracic and lumbar spinal fusions. SUMMARY OF BACKGROUND DATA: TXA has been extensively studied with regard to intraoperative blood loss and transfusion rates. Few studies have looked specifically at the effect of TXA on postoperative drain output. MATERIALS AND METHODS: We examined blood loss patterns in 617 consecutive adult patients undergoing lumbar and/or thoracic fusions at a single institution from January 2009 to 2016. These patients were divided into TXA and non-TXA, as well as high-dose and low-dose TXA, groups and analyzed using a propensity score to account for differences between cohorts. RESULTS: The TXA and non-TXA groups were demographically similar. The mean number of levels fused was higher in the TXA group (4.8 vs. 3.1 levels, P<0.01). There was a significant reduction in both intraoperative blood loss (77.7 mL per level, P=0.020) and postoperative drain output (83.3 mL per level, P=0.002) in the TXA group when examined on a per level fused basis, but no significant difference without controlling for a number of levels. Postoperative blood loss tended to be higher in the TXA group for surgeries involving >5 levels fused. There was a significantly less blood loss in the high-dose TKA group both intraoperatively (296.4 mL per level fused, P<0.001) and postoperatively (133.4 mL per level fused, P<0.001). CONCLUSIONS: TXA significantly reduced both intraoperative and postoperative blood loss in lumbar and thoracic fusions when examined on a per level basis. However, with surgeries involving fusions >5 levels, TXA may increase postoperative drain output, with those losses offset by reduced intraoperative blood loss. High-dose TXA further reduced both intraoperative and postoperative blood loss as compared with low-dose TXA.

An empiric analysis of 5 counter measures against surgical site infections following spine surgery-a pragmatic approach and review of the literature.

BACKGROUND CONTEXT: Surgical site infections (SSI) following spine surgery are debilitating complications to patients and costly to the healthcare system. PURPOSE: Review the impact and cost effectiveness of 5 SSI prevention interventions on SSI rates in an orthopedic spine surgery practice at a major quaternary healthcare system over a 10-year period. STUDY DESIGN: Retrospective observational study. PATIENT SAMPLE: All of the surgical patients of the 5 spine surgeons in our department over a 10-year period were included in this study. OUTCOME MEASURES: SSI rates per year, standardized infection ratios (SIR) for laminectomies and fusions during the most recent 3-year period, year of implementation, and frequency of use of the different interventions, cost of the techniques. METHODS: The SSI prevention techniques described in this paper include application of intrawound vancomycin powder, wound irrigation with dilute betadine solution, preoperative chlorhexidine gluconate scrubs, preoperative screening with nasal swabbing, and decolonization of S. aureus, and perioperative antibiotic administration. Our institution's infection prevention and control data were analyzed for the yearly SSI rates for the orthopedic spine surgery department from 2006 to 2016. In addition, our orthopedic spine surgeons were polled to determine with what frequency and duration they have been using the different SSI prevention interventions. RESULTS: SSI rates decreased from almost 6% per year the first year of observation to less than 2% per year in the final 6 years of this study. A SIR of less than 1.0 for each year was observed for laminectomies and fusions for the period from 2013 to 2016. All surgeons polled at our institution uniformly used perioperative antibiotics, Hibiclens scrub, and the nasal swab protocol since the implementation of these techniques. Some variability existed in the frequency and duration of betadine irrigation and application of vancomycin powder. A cost analysis demonstrated these methods to be nominal compared with the cost of treating a single SSI. CONCLUSIONS: It is possible to reduce SSI rates in spine surgery with easy, safe, and cost-effective protocols, when implemented in a standardized manner.

Do Cervical Spine Surgery Patients Recall Their Preoperative Status?: A Cohort Study of Recall Bias in Patient-reported Outcomes.

STUDY DESIGN: This is a prospective cohort study. OBJECTIVE: To characterize the accuracy of patient recollection of preoperative symptoms after cervical spine surgery. SUMMARY OF BACKGROUND DATA: Recall bias is a well-known source of systematic error. The accuracy of patient recall after cervical spine surgery remains unknown. METHODS: Consecutive patients undergoing cervical spine surgery for myelopathy or radiculopathy were enrolled. Neck and arm numeric pain scores and Neck Disability Indices were recorded preoperatively. Patients were asked to recall their preoperative status at either short (<1 y) or long-term (≥1 y) follow-up. Actual and recalled scores were compared using paired t tests and relations were quantified using the Pearson correlation coefficients. Multivariable linear regression was used to identify factors impacting recollection. RESULTS: In total, 73 patients with a mean age of 58.2 years were included. Compared with their preoperative scores, patients showed significant improvement in neck pain [mean difference (MD)=-2.9; 95% confidence intervals (CIs), -3.5 to -2.3], arm pain (MD, -3.4; 95% CI, -4.0 to -2.8), and disability (MD, -12.4%; 95% CI, -16.9 to -7.9). Patient recollection of preoperative status was significantly more severe than actual for neck pain (MD, +1.5; 95% CI, 0.8-2.2), arm pain (MD, +2.3; 95% CI, 1.6-3.0), and disability (MD, +5.8%; 95% CI, 2.4-9.2). Moderate correlation between actual and recalled scores with regard to neck (r=0.41), arm (r=0.50) pain, and disability (r=0.67) was seen. This was maintained across age, sex, and time between date of surgery and recollection. Over 30% of patients switched their predominant symptom from neck-to-arm pain or vice versa on recall of their preoperative symptoms. CONCLUSIONS: Relying on patient recollection does not provide an accurate measure of preoperative status after cervical spine surgery. Prospective and not retrospective collection of patient-reported outcomes remain the gold standard to measure and interpret outcomes after cervical spine surgery. Recall bias has the potential to affect patient satisfaction and requires further study.

Does Recombinant Human Bone Morphogenic Protein 2 Affect Perioperative Blood Loss after Lumbar and Thoracic Spinal Fusion?

STUDY DESIGN: Retrospective cohort design. PURPOSE: This study aimed to determine whether recombinant human bone morphogenic protein 2 (rhBMP-2) reduces total perioperative blood loss during lumbar and thoracic fusion. OVERVIEW OF LITERATURE: Previous studies on rhBMP-2 versus iliac crest bone grafting in thoracic and lumbar fusions have yielded mixed results regarding reductions in blood loss and have largely neglected the postoperative period when analyzing total blood loss. Additionally, these studies have been limited by heterogeneity and sample size. METHODS: We analyzed the blood loss patterns of 617 consecutive adult patients undergoing lumbar and/or thoracic fusions requiring subfascial drain placement at a single institution from January 2009 to December 2016. Patients were divided into BMP and non-BMP cohorts, and a propensity score analysis was conducted to account for the differences between cohorts. RESULTS: At a per-level fused basis, the BMP group exhibited a significant reduction in the intraoperative (66.1 mL per-level fused basis; 95% confidence interval [CI], 127.9 to 4.25 mL; p =0.036) and total perioperative blood loss (100.7 mL per-level fused basis; 95% CI, 200.9 to 0.5 mL; p =0.049). However, no significant differences were observed in an analysis when not controlling for the number of levels or when examining the postoperative drain output. CONCLUSIONS: RhBMP-2 appears to reduce both intraoperative and total blood loss during lumbar and thoracic fusions on a per-level fused basis. This total reduction in blood loss was achieved via intraoperative effects because RhBMP-2 had no significant effect on the postoperative drain output.

Does Subcutaneous Infiltration of Liposomal Bupivacaine Following Single-Level Transforaminal Lumbar Interbody Fusion Surgery Improve Immediate Postoperative Pain Control?

STUDY DESIGN: Retrospective case-control study using prospectively collected data. PURPOSE: Evaluate the impact of liposomal bupivacaine (LB) on postoperative pain management and narcotic use following standardized single-level low lumbar transforaminal lumbar interbody fusion (TLIF). OVERVIEW OF LITERATURE: Poor pain control after surgery has been linked with decreased pain satisfaction and increased economic burden. Unfortunately, opioids have many limitations and side effects despite being the primary treatment of postoperative pain. LB may be a form of pre-emptive analgesia used to reduce the use of postoperative narcotics as evidence in other studies evaluating its use in single-level microdiskectomies. METHODS: The infiltration of LB subcutaneously during wound closure was performed by a single surgeon beginning in July 2014 for all single-level lumbar TLIF spinal surgeries at Landstuhl Regional Medical Center. This cohort was compared against a control cohort of patients who underwent the same surgery by the same surgeon in the preceding 6 months. Statistical analysis was performed on relevant variables including: morphine equivalents of narcotic medication used (primary outcome), length of hospitalization, Visual Analog Scale pain scores, and total time spent on a patient-controlled analgesia (PCA) pump. RESULTS: A total of 30 patients were included in this study; 16 were in the intervention cohort and 14 were in the control cohort. The morphine equivalents of intravenous narcotic use postoperatively were significantly less in the LB cohort from day of surgery to postoperative day 3. Although the differences lost their statistical significance, the trend remained for total (oral and intravenous) narcotic consumption to be lower in the LB group. The patients who received the study intervention required an acute pain service consult less frequently (62.5% in LB cohort vs. 78.6% in control cohort). The amount of time spent on a PCA pump in the LB group was 31 hours versus 47 hours in the control group (p=0.1506). CONCLUSIONS: Local infiltration of LB postoperatively to the subcutaneous tissues during closure following TLIF significantly decreased the amount of intravenous narcotic medication required by patients. Well-powered prospective studies are still needed to determine optimal dosing and confirm benefits of LB on total narcotic consumption and other measures of pain control following major spinal surgery.

"The Jackson Table Is a Pain in the ": A Qualitative Study of Providers' Perception Toward a Spinal Surgery Table.

OBJECTIVE: The aim of this study was to define health care providers' perceptions toward prone patient positioning for spine surgery using the Jackson Table, which has not been hitherto explored. METHODS: We analyzed open-ended questionnaire data and interviews conducted with the spine surgical team regarding the current process of spinal positioning/repositioning using the Jackson Table. Participants were asked to provide an open-ended explanation as to whether they think the current process of spinal positioning/repositioning is safe for the staff or patients. Follow-up qualitative interviews were conducted with 11 of the participants to gain an in-depth understanding of the challenges and safety issues related to prone patient positioning. RESULTS: Data analysis resulted in 6 main categories: general challenges with patient positioning, role-specific challenges, challenges with the Jackson Table and the "sandwich" mechanism, safety concerns for patients, safety concerns for the medical staff, and recommendations for best practices. CONCLUSIONS: This study is relevant to everyday practice for spinal surgical team members and advances our understanding of how surgical teams qualitatively view the current process of patient positioning for spinal surgery. Providers recommended best practices for using the Jackson Table, which can be achieved through standardized practice for transfer of patients, educational tools, and checklists for equipment before patient transfer and positioning. This research has identified several important practice opportunities for improving provider and patient safety in spine surgery.

RNA sequencing identifies gene regulatory networks controlling extracellular matrix synthesis in intervertebral disk tissues.

Degenerative disk disease of the spine is a major cause of back pain and disability. Optimization of regenerative medical therapies for degenerative disk disease requires a deep mechanistic understanding of the factors controlling the structural integrity of spinal tissues. In this investigation, we sought to identify candidate regulatory genes controlling extracellular matrix synthesis in spinal tissues. To achieve this goal we performed high throughput next generation RNA sequencing on 39 annulus fibrosus and 21 nucleus pulposus human tissue samples. Specimens were collected from patients undergoing surgical discectomy for the treatment of degenerative disk disease. Our studies identified associations between extracellular matrix genes, growth factors, and other important regulatory molecules. The fibrous matrix characteristic of annulus fibrosus was associated with expression of the growth factors platelet derived growth factor beta (PDGFB), vascular endothelial growth factor C (VEGFC), and fibroblast growth factor 9 (FGF9). Additionally we observed high expression of multiple signaling proteins involved in the NOTCH and WNT signaling cascades. Nucleus pulposus extracellular matrix related genes were associated with the expression of numerous diffusible growth factors largely associated with the transforming growth signaling cascade, including transforming factor alpha (TGFA), inhibin alpha (INHA), inhibin beta A (INHBA), bone morphogenetic proteins (BMP2, BMP6), and others. CLINICAL SIGNIFICANCE: this investigation provides important data on extracellular matrix gene regulatory networks in disk tissues. This information can be used to optimize pharmacologic, stem cell, and tissue engineering strategies for regeneration of the intervertebral disk and the treatment of back pain. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1356-1369, 2018.

Thromboembolic Disease after Cervical Spine Surgery: A Review of 5,405 Surgical Procedures and Matched Cohort Analysis.

STUDY DESIGN: Retrospective matched cohort analysis. OBJECTIVE: The majority of the literature on venous thromboembolism (VTE) after spine surgery is limited to studies of thoracolumbar surgery. Less is known regarding the incidence of VTE and associated risk factors following cervical spine surgery. METHODS: A total of 5,405 patients at our institution underwent cervical diskectomy, laminectomy, corpectomy, laminoplasty, or fusion between 1995 and 2012; 85 of the 5,405 patients (1.57%) suffered either a DVT (55) or pulmonary embolus (51) within 30 days postoperatively. The cases were matched 1:2 to controls based on age, sex, and date of surgery. Data regarding multiple perioperative factors, demographics, and comorbidities was collected. RESULTS: Several risk factors were identified for VTE. Significant medical comorbidities included chronic venous insufficiency (odds ratio [OR] = 3.40), atrial fibrillation (OR = 2.69), obesity (OR = 2.67), and ischemic heart disease (OR = 2.18). Staged surgery (OR = 28.0), paralysis (OR = 19.0), combined approach (OR = 7.46), surgery for infection (OR = 18.5), surgery for trauma (OR = 11.1), comorbid traumatic injuries (OR > 10), oncologic procedures (OR = 5.2), use of iliac crest autograft (OR = 4.16), two or more surgical levels (OR = 3.48), blood loss > 300 mL (OR = 1.66), and length of stay 5 days or greater (OR = 3.47) were all found to be risk factors for VTE (p < 0.05) in univariate analysis. Multivariate analysis found staged surgery (OR = 35.7), paralysis (OR = 7.86), and nonelective surgery (OR = 6.29) to be independent risk factors for VTE. CONCLUSIONS: Although the incidence of VTE following cervical spine surgery is low, we identified several risk factors that may be predictive. More aggressive approaches to prophylaxis and surveillance in certain patient populations may be warranted.