Faculty Bibliography

BACKGROUND:Patients with less severe adult spinal deformity undergo surgical correction and often achieve good clinical outcomes. However, it is not well understood how much clinical improvement is due to sagittal correction rather than treatment of the spondylotic process. PURPOSE/OBJECTIVE:Determine baseline thresholds in radiographic parameters that, when exceeded, may result in substantive clinical improvement from surgical correction. STUDY DESIGN/METHODS:Retrospective. METHODS:ASD patients with BL and 2-year(2Y) data were included. Parameters assessed: SVA, PI-LL, PT, T1PA, L1PA, L4-S1 Lordosis, C2-C7 SVA(cSVA), C2-T3, C2 Slope(C2S). Outcomes: Good Outcome(GO) at 2Y: [Meeting either: 1) SCB for ODI(change greater than 18.8), or 2) ODI<15 and SRS-Total>4.5. Binary logistic regression assessed each parameter to determine if correction was more likely needed to achieve GO. Conditional inference tree(CIT) run machine learning analysis generated baseline thresholds for each parameter, above which, correction was necessary to achieve GO. RESULTS:We included 431 ASD patients. There were 223(50%) that achieved a GO by two years. Binary logistic regression analysis demonstrated, with increasing baseline severity in deformity, sagittal correction was more often seen in those achieving GO for each parameter(all P<0.001). Of patients with baseline T1PA above the threshold, 95% required correction to meet Good Outcome(95% vs. 54%,P<0.001). A baseline PI-LL above 10° (74% of patients meeting GO) needed correction to achieve GO (OR: 2.6,[95% CI 1.4-4.8]). A baseline C2 slope above 15° also necessitated correction to obtain clinical success (OR: 7.7,[95% CI 3.7-15.7]). CONCLUSION/CONCLUSIONS:Our study highlighted point may be present at which sagittal correction has an outsized influence on clinical improvement, reflecting the line where deformity becomes a significant contributor to disability. These new thresholds give us insight into which patients may be more suitable for sagittal correction, as opposed to intervention for the spondylotic process only, leading to a more efficient utility of surgical intervention for adult spinal deformity. LEVEL OF EVIDENCE/METHODS:III.

PURPOSE/OBJECTIVE:Single position surgery has demonstrated to reduce hospital length of stay, operative times, blood loss, postoperative pain, ileus, and complications. ALIF and LLIF surgeries offer advantages of placing large interbody devices under direct compression and can be performed by a minimally invasive approach in the lateral position. Furthermore, simultaneous access to the anterior and posterior column is possible in the lateral position without the need for patient repositioning. The purpose of this study is to outline the anatomical and technical considerations for performing anterior lumbar interbody fusion (ALIF) in the lateral decubitus position. METHODS:Surgical technique and technical considerations for reconstruction of the anterior column in the lateral position by ALIF at the L4-5 and L5-S1 levels. RESULTS:Topics outlined in this review include: Operating room layout and patient positioning; surgical anatomy and approach; vessel mobilization and retractor placement for L4-5 and L5-S1 lateral ALIF exposure, in addition to comparative technique of disc space preparation, trialing and implant placement compared to the supine ALIF procedure. CONCLUSIONS:Anterior exposure performed in the lateral decubitus position allows safe-, minimally invasive access and implant placement in ALIF. The approach requires less peritoneal and vessel retraction than in a supine position, in addition to allowing simultaneous access to the anterior and posterior columns when performing 360° Anterior-Posterior fusion.

BACKGROUND CONTEXT: Previous orthopedic literature has shown that patients with diabetes mellitus (DM) are more likely to develop complications in the postoperative period. To date, however, no study has assessed the specific pre- and postoperative risk factors that may contribute to this association for diabetic patients undergoing adult spinal deformity surgery. PURPOSE: Establish relevant risk factors for postoperative complications in a cohort of diabetic patients undergoing spinal deformity surgery. STUDY DESIGN/SETTING: Single-center retrospective cohort study. PATIENT SAMPLE: A total of 138 patients with DM who underwent spinal deformity surgery at a single academic hospital from 2012-2019. OUTCOME MEASURES: Primary outcomes were the development of any post-operative complications. These complications included the development of neurologic complications, urinary complications, cardiac complications, pulmonary complications, venous thromboembolism (VTE) and surgical site infections (SSI).
METHOD(S): This study is a retrospective cohort review of diabetic patients undergoing spinal deformity surgery, with 5 levels fused at a single academic medical center. Patients' age, BMI, levels fused, pre- and postoperative hemoglobin (Hgb), hematocrit (HCT) and preoperative HbA1C were collected. T-test and chi-square analyses were used to compare relevant outcomes. Significance was set to p<0.05.
RESULT(S): A total of 138 patients with DM met the inclusion criteria and were included in the analysis. Of these, 50.7% of the total cohort developed a postoperative complication within 90 days of the index surgery. Patients who developed postoperative complications were noted to have significantly lower postoperative Hgb (9.82+/-1.46 g/dL vs 10.72+/-1.76 g/dL, p=0.002) postoperative HCT (28.8+/-3.92% vs 32.60+/-4.61%, p<0.001) and significantly greater number of levels fused (9.49+/-3.74 vs 7.47+/-3.16, p=0.001). Diabetic patients who developed cardiac complications had significantly lower postoperative Hgb (9.47+/-1.50 g/dL vs 10.40+/-1.66 g/dL, p=0.021) and HCT (27.87+/-3.16% vs 31.15+/-4.72%, p=0.003) compared with those who did not. Diabetic patients who developed urinary complications were noted to be older on average (72.56+/-8.20 vs 64.43+/-11.70 years, p=0.043), while patients who developed VTE and pulmonary complications were noted to have significantly higher numbers of levels fused (VTE: 14.00+/-3.61 vs 8.37+/-3.51, p=0.007; PC: 10.82+/-4.14 vs 8.29+/-3.49, p=0.025)Finally, diabetic patients who developed a surgical site infection had significantly lower postoperative HCT (26.74+/-3.27% vs 30.86+/-4.64%, p=0.022) than those who did not. Multivariate logistic regression analysis showed that postoperative HCT (OR: 0.765 [0.613-1.098], p=0.001) and number of levels fused (OR: 1.243 [1.084-1.425], p=0.002) were predictive of development of any postoperative complication, when controlled for BMI, age, and and postoperative Hgb. Postoperative HCT was an independent predictor of the development of cardiac complications (OR: 0.827 [0.692-0.989], p=0.037) and SSI (OR: 0.709 [0.528-0.952], p=0.022).
CONCLUSION(S): Postoperative HCT is predictive of the development of postoperative complications in general, and more specifically the development of cardiac complications and surgical site infections. Along with blood-glucose and HbA1C, it should be closely monitored perioperatively in diabetic patients undergoing spinal deformity surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Reducing fluoroscopy time and radiation exposure in the operating room is beneficial for the patient and surgical team. Placement of an interbody device during lateral transpsoas approach is traditionally carried out using anterior-posterior and lateral fluoroscopy. In this setting, 3-dimensional computed tomography (CT)-based spinal navigation of cage and pedicle screw/rod placement for LLIF procedure may result in decreased radiation exposure compared with fluoroscopically-guided LLIF. We sought to present our experience with the use of CT-based spinal navigation for the LLIF procedure and evaluate rates of intraoperative complications and radiation exposure. PURPOSE: To determine if computer-navigation guided LLIF will have equivalent outcomes with decreased radiation dose compared to fluoroscopy-guided LLIF. STUDY DESIGN/SETTING: Single-center retrospective review. PATIENT SAMPLE: This study included 250 patients over 18 years of age who underwent LLIF with <4 levels fused (age: 61.4 +/- 10.8 yrs, BMI: 29.7 +/- 6.1 7 kg/m2). OUTCOME MEASURES: Intraoperative and 90-day complications, radiation exposure and cage placement.
METHOD(S): Patients were separated into two groups: fluoroscopy-guided LLIF (n=224), and navigated LLIF (n=26). Cage placement was assessed on postoperative radiographs by dividing the disc space into quarters, anterior to posterior.
RESULT(S): In terms of operative characteristics, fluoroscopy dosage was significantly greater in the fluoroscopically-guided LLIF cohort (55.1 +/- 57.4 mGy vs 34.0 +/- 24.9 mGy, p=0.002). There were no significant differences between fluoroscopically-guided LLIFs and navigated LLIFs in overall intraoperative complication rate (4% Fluoro vs 0% Nav, p=0.3), rate of durotomy (2.2 % Fluoro vs 0% Nav, p=0.44), or estimated blood loss (322 +/- 330.3 cc Flouro vs 299.5 +/- 198.6 cc Nav, p=0.6). The rate of postoperative complications (26.8% Fluoro vs 26.9% Nav), neurologic complications (5.4% Fluoro vs 3.8% Nav), surgical site infections (1.3% Fluoro vs 3.8% Nav), mechanical complications (1.8% Fluoro vs 0% Nav) was not significantly different. There was no significant difference in the rate of unplanned return to the operating room within 90 days (1.8% Fluoro vs 0% Nav). Cage placement was similar between the two groups (p=0.29).
CONCLUSION(S): We report an average radiation exposure with navigated LLIFs of 34.0 mGy, significantly lower than the 55.1 mGy in the fluoroscopically-guided LLIF group. The length of stay and perioperative complication rate was equivalent between the groups. These data support the use of CT-based navigation for placement of the cage and pedicle screws/rod construct for LLIF procedure. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Sagittal alignment is integral to a patient's quality of life. Posterior spinal fusion (PSF) is currently the standard for correcting adolescent idiopathic scoliosis (AIS). Vertebral body tethering (VBT) is a fusionless growth modulating surgical technique used to treat AIS. It relies on the Hueter-Volkmann Law. Indications for this procedure include patients who have coronal curves up to 50degree, growth remaining, and no excessive thoracic kyphosis. VBT has been shown to have good coronal plane deformity correction. There have been fewer examinations of the sagittal effects of VBT. PURPOSE: To determine if VBT is a non-inferior treatment for correction of AIS with regard to sagittal alignment compared to PSF. STUDY DESIGN/SETTING: Multicenter retrospective cohort study. PATIENT SAMPLE: Patients with AIS who underwent correction surgeries with LIV in the lumbar spine from 2013 to 2021 with pre- and minimum two-year postoperative standing full spine plain films. OUTCOME MEASURES: Sagittal vertical axis (SVA), cervical SVA (cSVA), pelvic tilt (PT), thoracic kyphosis (TK), cervical lordosis (CL), L4-S1 lordosis (L4L), T1 pelvic angle (TPA) and pelvic incidence lumbar lordosis mismatch (PI-LL).
METHOD(S): Radiographic analyses was completed with independent samples t-test with significance set to p <0.05.
RESULT(S): A total of 99 patients were included, 49 VBT and 50 PSF. There were no differences in age or levels instrumented between groups. The VBT cohort Lenke class breakdown is 23% 1A, 13% 1C, 31% 3C. 18% 5C, and 15% 6C, while the PSF cohort consisted of 42% 1A, 6% 1B, 2% 2C, 2% 3B, 12% 3C, 2% 5B, 24% 5C, and 10% 6C. At Baseline, the VBT cohort had lower SVA (-0.7mm+/-3.7 vs 2.2mm+/-5.0, p=0.001), CL (-0.9degree+/-18.2 vs 11.6degree+/-12.8, p=0.001), L4-S1 Lordosis (20.7degree+/-16.0 vs 41.6degree+/-10.2, p=0.001), and higher cSVA (3.3mm+/-1.6 vs -0.95mm+/-3.1, p=0.001) than those who were fused. Postoperatively, VBT patients have an overall higher L4-S1 Lordosis (36.0degree+/-10.1vs 18.3degree+/-12.5, p=0.001), cSVA (3.4mm+/-1.4 vs -3.7mm+/-2.1, p=0.001), and lower CL (-4.3degree+/-18.4 vs 7.0degree+/-12.2, p=0.001). The PSF cohort had a larger change in cSVA (2.8mm+/-4.0 vs 0mm+/-1.6, p=0.001) from baseline to 2-year follow-up compared to VBT. No differences in the change of L4-S1 Lordosis (VBT 1.5degree+/-12.3 vs 4.1degree+/-10.9, p=0.3), TPA (VBT -1.6degree+/-6.8 vs -1.4degree+/-8.5, p=0.89), PT (VBT -0.5degree+/-7.8 vs -1.9degree+/-8.5, p=0.42), or PI-LL (0.2degree+/-12.0 vs -0.5degree+/-14.0, p=0.81) were observed.
CONCLUSION(S): VBT and PSF for AIS result in statistically similar changes in sagittal alignment parameters. The fact that we showed similar results comparing sagittal alignment in fusion and VBT groups indicates that VBT is non-inferior from a sagittal perspective. It is important to maintain sagittal alignment when correcting AIS. Future work can examine the long-term effect of VBT on sagittal alignment. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: In recent years spine surgeons have utilized different techniques and approaches to perform lumbar interbody fusion surgery. We sought to analyze the difference in outcomes between traditional open transforaminal lumbar interbody fusion (O-TLIF), minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF), dual position anterior/lateral lumbar interbody fusion with posterior instrumentation (Dual ALIF/LLIF), and single position anterior/lateral lumbar interbody fusion with posterior instrumentation (Single ALIF/LLIF). PURPOSE: To analyze the perioperative and postoperative outcomes of patient undergoing TLIF, MIS TLIF, Dual ALIF/LLIF, and Single ALIF/LLIF. STUDY DESIGN/SETTING: Retrospective cohort study at a single institution. PATIENT SAMPLE: Patients undergoing O-TLIF, MIS TLIF, Dual ALIF/LLIF, or Single ALIF/LLIF from 2014 to 2020. OUTCOME MEASURES: Operative time, estimated blood loss (EBL), length of stay (LOS), radiation dose, intraoperative and postoperative complications, and return to OR within 90 days.
METHOD(S): Patients who underwent single level lumbar interbody fusion surgery were analyzed. Patient charts were reviewed for operative time, EBL, LOS, radiation dose, intraoperative and postoperative complications, and return to OR within 90 days. Differences were assessed by ANOVA.
RESULT(S): A total of 1,226 patients underwent a single level lumbar interbody fusion (440 O-TLIF, 423 MIS TLIF, 316 Dual ALIF/LLIF, 47 Single ALIF/LLIF). There were no significant differences in BMI or gender between the groups, but in the O-TLIF cohort average age (60) was higher than MIS-TLIF (54), Dual ALIF/LLIF(52), and Single ALIF/LLIF (50) p < 0.001. There were also significant differences in average operative time (221 mins O-TLIF, 212 mins MIS TLIF, 277 mins dual ALIF/LLIF, 277 mins single ALIF/LLIF, p < 0.001), EBL (360 ml O-TLIF, 167ml MIS TLIF, 235 ml Dual ALIF/LLIF, 253 ml Single ALIF/LLIF, p<0.001), radiation dose (20 mGy O-TLIF, 51 mGy MIS TLIF, 43 mGy Dual ALIF/LLIF, 62 mGy Single ALIF/LLIF, p < 0.001). There was no difference in LOS, intraoperative complications, or 90-day complications between the groups, except a higher rate of neurological deficit in dual ALIF/LLIF (1.6%, p < 0.03). Post hoc analysis demonstrated statistical significance in operative time in the Dual ALIF/LLIF as compared to all the other groups. O-TLIF demonstrated a larger EBL and less radiation as compared to all the other groups as well as a longer operative time than Single ALIF/LLIF. Dual ALIF/LLIF demonstrated a longer operative time and increased rate of neurological deficit as compared to MIS TLIF.
CONCLUSION(S): In comparing different techniques for single level lumbar interbody fusion there were similar outcomes in LOS, perioperative complications and 90-day complications between all the groups. Open TLIF was associated with increased estimate blood loss and less radiation than all the other groups Dual position ALIF/LLIF surgery was associated with a longer operative time than all the other groups. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: VBT takes advantage of the Hueter-Volkmann principle, and modulates growth across intervertebral disc spaces with a tensioned tether secured at the lateral aspects of vertebral bodies. Cervical deformity in AIS patients is associated with lower health related quality of life. PSF constructs have been shown to improve cervical deformity, however, to date, these relationships have not been described in patients treated with VBT. PURPOSE: Determine if cervical sagittal alignment parameters following VBT for correction of AIS are similar to what is observed following PSF. STUDY DESIGN/SETTING: Multi-center retrospective cohort study. PATIENT SAMPLE: Patients with AIS that undergo correction surgeries with LIV in the lumbar spine from 2013 to 2021 with pre- and 2-year postop standing full body plain films available. OUTCOME MEASURES: Outcome measures: Age, height, weight, BMI, Risser score, LIV and levels instrumented. Radiographic analysis included pre- and postop C2 to C7 sagittal vertical axis (cSVA), cervical lordosis angle (CL), T1 slope and thoracic kyphosis (TK).
METHOD(S): Measures were compared using independent samples t-tests, significance set at p<0.05.
RESULT(S): A total of 99 patients: 49 VBT and 50 fusions. The VBT cohort Lenke class breakdown is 23% 1A, 13% 1C, 31% 3C; 18% 5C, and 15% 6C, while the PSF cohort consisted of 42% 1A, 6% 1B, 2% 2C, 2% 3B, 12% 3C, 2% 5B, 24% 5C, and 10% 6C. There were no significant differences with regard to patient age or number of levels instrumented. Patients included in the VBT cohort had a lower level of bone maturity as defined by Risser class (1.6+/-0.9 vs 2.6+/-1.8, p=0.001). The VBT cohort had higher baseline cSVA (3.4mm+/-1.6 vs -1.0mm+/-3.1, 0.001) and less CL (-0.6degree+/-18.2 vs 11.6degree+/-12.8, p=0.001) than the fusion cohort. No differences in baseline T1 slope or Thoracic Kyphosis was observed. VBT patients also had higher 2-year cSVA (3.4mm+/-1.4 vs -3.7mm+/-2.1, p=0.001) and less CL (-4.0+/-18.5 vs 7.0+/-12.2, p=0.001) compared to fusion patients. The PSF group had a significantly greater correction in cSVA than the VBT group (2.8mm+/-4.0 vs 0mm+/-1.6, p=0.001). Both groups displayed improvement in radiographic parameters of cervical and thoracic alignment including CL (VBT 3.3degreevs 4.3degree, p=0.74), T1 slope (VBT -4.3degreevs -4.9degree, p=0.81) and TK (VBT -6.1degreevs -3.9degree, p=0.47). After PSM for Lenke classification, 66 patients remained: 33 VBT, 33 PSF. The PSF group continued to demonstrate greater improvement in cSVA than the VBT group (3.2mm+/-3.0 vs -0.3+/-1.8, p=0.001.
CONCLUSION(S): VBT and PSF both improve radiographic parameters of cervical alignment in AIS patients; however, PSF showed greater correction of cSVA at 2-year followup. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The ACS-NSQIP and SpineSage are both easy to use and readily available online perioperative risk calculators The ACS-NSQIP calculator predicts perioperative complications after surgery, but lacks more spine-specific predictors. The SpineSage platform was developed as a tool built for predicting complications in spine surgery. While a limited number of studies have shown it be predictive of both overall and major medical complications in spine surgery, large external validation studies are limited and none have directly compared NSQIP against SpineSage in the same cohort of spine surgery patients. PURPOSE: Assess the ACS-NSQIP Risk Calculator and SpineSage informatics platform for prediction of perioperative complications in spine surgery STUDY DESIGN/SETTING: Retrospective. PATIENT SAMPLE: A total of 440 patients undergoing thoracolumbar spine with or without fusion. OUTCOME MEASURES: Any complication, serious complication, pneumonia, cardiac, dural tear, SSI, UTI, VTE, reoperation, death and LOS METHODS: Each patient was entered into the ACS-NSQIP and SpineSage calculators and predicted risk for specific complications were directly compared to actual risks. Paired t-tests compared the differences between calculators and their predictability of complications. Patients were ranked based on risk predicted for each complication and the highest tertile for each was isolated. Multivariate regression controlling for age and gender was used to determine if the highest tertile for each risk calculator had predictability in complications following spine surgery.
RESULT(S): Mean LOS 4.2+3 days, EBL 444+300 mL, operative time 256+240 min, and levels instrumented 2.1+2.3. When assessing the four complications predicted by SpineSage there were significant differences in three of the four variables, as SpineSage underpredicted the risk of all and serious-complications (p.5). Both calculator tertiles were trending towards significance for major medical complications (SpineSage: OR: 2.0, [0.94-4.23], p=.073; ACS-NSQIP: OR: 1.8,[0.96-3.48],p=.067). When examining any medical risk, only ACS NSQIP had significant predictability for any medical complication (OR: 2.1, [1.3-3.3]; p=.003).
CONCLUSION(S): Similar to previous studies, the ACS-NSQIP score underpredicted most complications, with the exception of LOS and death. In contrast to previous studies, our data suggest SpineSage was not predictive of actual rates of complications. As both calculators are highly accessible and provide at least some objective perioperative risk data points, we recommend them as a guiding tool but not as an absolute endpoint for clinical decision making as they may be inaccurate and insensitive. Further, higher powered studies elucidating the findings in this study should be conducted. Additionally, the assessment of these calculators for a specific subset of patients, such as deformity, degenerative or pediatrics, can further help guide clinicians regarding the utility of these calculators for their particular patient populations. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Diabetic patients with elevated hemoglobin A1C (HbA1C) are at higher risk of developing complications after surgery than their nondiabetic peers. This is especially true of wound complications, including wound infections. Previous research has shown this relationship to be multifactorial, so more investigation is needed into these complications. PURPOSE: Establish pertinent factors which contribute to increased wound complication incidence among diabetic patients undergoing thoracolumbar fusion. STUDY DESIGN/SETTING: Single center retrospective cohort study. PATIENT SAMPLE: This study included 228 patients with a diagnosis of diabetes mellitus who underwent thoracic, lumbar, or thoracolumbar posterior spinal fusion (PSF) from 2013-2018 with preoperative HbA1C values. Patients without preoperative HbA1C results or undergoing cervical fusions were excluded. OUTCOME MEASURES: Development of wound complications and infection in the perioperative period were recorded for analysis. Wound complications were defined as dehiscence, superficial SSI and deep SSI.
METHOD(S): Significant perioperative complications were determined using t-test and chi-square analyses. Complications were tested against confounding factors using binary logistic regressions. Efficacy of various preoperative demographic measures as markers for complication was determined using Receiver Operating Characteristic (ROC) analyses. Cutoff points were calculated by Youden's index. Significance set at p <0.05.
RESULT(S): A total of 228 patients met inclusion. Significant differences in BMI were noted between patients who developed infection (n=7) and those who did not (37.5 kg/m² vs 32.0 kg/m²; p=0.039). In addition, binary logistic regression showed that, controlled for HbA1C, BMI was a significant predictor of infection (OR: 1.110; p=0.043). ROC curve demonstrated an AUC of 0.754 (p=0.022) and Youden's J calculated the cutoff point to be 34.08 kg/m² (Spec: 64.3%, Sens: 85.7%). No differences between those with postop wound complications were noted in HbA1C (7.29 vs 6.88; p=0.345), age (70.14 vs 64.92; p=0.197), gender (vs 71.4% female vs 55.5% female; p=0.469), smoking status (28.6% smoking history vs 33.9% smoking history), levels fused (2.71 vs 2.62; p=0.931), LOS (3.29 vs 4.82; p=0.243). Sub-analysis of superficial infections revealed no significant differences in HbA1C (7.15 vs 6.88; p=0.565), age (70.8 vs 64.9; p=0.175), BMI (36.5 vs 32.1; p=0.114), levels fused (2.5 vs 2.6; p=0.911), gender (66.7% female vs 55.4% female; p=0.697), smoking status (33.3% smoking history vs 33.7% smoking history; p=1.000), or LOS (2.8 vs 4.8; p=0.159). Subanalysis of deep SSI revealed only one infection.
CONCLUSION(S): BMI above 34.08 kg/m² is a significant predictor of postoperative infection in diabetic patients undergoing posterior fusion. To ensure optimal outcomes, diabetic patients should be encouraged to get below this threshold before surgery. More research must be done to further establish the relationship of BMI with regard to superficial and deep infections. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Indirect decompression technique may be limited in that it does not include direct removal of the offending intervertebral disc or osteophyte protruding into the canal. PURPOSE: This study evaluates resolution of radiculopathy and perioperative complications in lumbar fusion with indirect or direct decompression techniques. STUDY DESIGN/SETTING: Retrospective analysis of large single center academic institution. PATIENT SAMPLE: This study included 116 single-level lumbar fusion patients with preoperative radiculopathy from 2012 to 2021. OUTCOME MEASURES: Resolution of radiculopathy, visual analog scores (VAS), perioperative complications, motor scores.
METHOD(S): Patients 18 years of age diagnosed with preoperative radiculopathy undergoing single-level lumbar fusion with up to two-year follow-up were grouped by indirect and direct decompression. Direct decompression group included TLIF with or without direct decompression procedure as well as ALIF and LLIF with direct decompression procedure. Indirect decompression group included ALIF and LLIF without direct decompression procedure. Propensity score matching (PSM) was used to control for differences in age between groups. Outcome measures were compared between groups using means comparison tests. Logistic regression analysis was used to correlate decompression type with symptom resolution over time.
RESULT(S): A total of 116 patients were included in this analysis: 58 direct decompression (mean 53.9y, 67.2% female) and 58 indirect decompression (mean 54.6y, 61.4% female). Direct decompression patients experienced greater blood loss relative to indirect decompression patients (242.4 +/- 128.5 vs 171.79 +/- 143.9 mL, p=0.007). Additionally, direct decompressionpatients experienced full resolution of radiculopathy at 3 months postop at a greater rate than those in the indirect decompression group (OR: 4.742, [1.97-11.41]; 53.1% vs 13.73%, p=0.002). At 6 months, direct decompression patients demonstrated a significantly larger reduction in VAS score 6 months postop (-2.889 +/- 2.3 vs -0.897 +/- 4.3, p=0.044). With regard to motor function, direct decompression patients had improved motor score with respect to the L5 dermatome at 6 months compared to indirect decompression patients (DELTAmotor score from baseline: 0.1714 +/- 0.453 vs -0.024 +/- 0.154, p=0.019).
CONCLUSION(S): Patients who underwent direct decompression experienced significantly greater resolution of preoperative lower extremity radiculopathy at 3 months compared with those who underwent ID alone. At 6 and 12 months, no differences were noted between the two groups. There were no differences in complication rates. At 6 months postop, direct decompression patients had greater improvement in preoperative motor deficit than ID patients. In particularly debilitated patients, these findings may influence surgeons to perform a direct decompression to achieve more rapid resolution of radiculopathy symptoms. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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