Racial and Socioeconomic Disparities in Laminoplasty Versus Laminectomy With Fusion in Patients With Cervical Spondylosis

STUDY DESIGN

A retrospective cohort study using prospectively collected data.

OBJECTIVE

The aim of this study was to investigate preoperative differences in racial and socioeconomic factors in patients undergoing laminoplasty (LP) versus laminectomy and fusion (LF) for degenerative cervical myelopathy (DCM).

SUMMARY OF BACKGROUND DATA

DCM is prevalent in the United States, requiring surgical intervention to prevent neurological degeneration. While LF is utilized more frequently, LP is an emerging alternative. Previous studies have demonstrated similar neurological outcomes for both procedures. However, treatment selection is primarily at the discretion of the surgeon and may be influenced by social determinants of health that impact surgical outcomes.

MATERIALS AND METHODS

The Quality Outcome Database (QOD), a national spine registry, was queried for adult patients who underwent either LP or LF for the management of DCM. Covariates associated with socioeconomic status, pain and disability, and demographic and medical history were collected. Multivariate logistic regression was performed to assess patient factors associated with undergoing LP versus LF.

RESULTS

Of 1673 DCM patients, 157 (9.4%) underwent LP and 1516 (90.6%) underwent LF. A significantly greater proportion of LP patients had private insurance (P<0.001), a greater than high school level education (P<0.001), were employed (P<0.001), and underwent primary surgery (P<0.001). LP patients reported significantly lower baseline neck/arm pain and Neck Disability Index (P<0.001). In the multivariate regression model, lower baseline neck pain [odds ratio (OR)=0.915, P=0.001], identifying as non-Caucasian (OR=2.082, P<0.032), being employed (OR=1.592, P=0.023), and having a greater than high school level education (OR=1.845, P<0.001) were associated with undergoing LP rather than LF.

CONCLUSIONS

In DCM patients undergoing surgery, factors associated with patients undergoing LP versus LF included lower baseline neck pain, non-Caucasian race, higher education, and employment. While symptomatology may influence the decision to choose LP over LF, there may also be socioeconomic factors at play. The trend of more educated and employed patients undergoing LP warrants further investigation.

Impact of unplanned readmissions on lumbar surgery outcomes: a national study of 33,447 patients

BACKGROUND CONTEXT

Unplanned readmissions following lumbar spine surgery have immense clinical and financial implications. However, little is known regarding the impact of unplanned readmissions on patient-reported outcomes (PROs) following lumbar spine surgery.

PURPOSE

To evaluate the impact of unplanned readmissions, including specific readmission reasons, on patient reported outcomes 12 months after lumbar spine surgery.

STUDY DESIGN/SETTING

A retrospective cohort study of prospectively collected data was conducted using patients included in the lumbar module of the Quality and Outcomes Database (QOD), a national, multicenter spine registry.

PATIENT SAMPLE

A total of 33,447 patients who underwent elective lumbar spine surgery for degenerative diseases were included. Mean age was 59.8 (SD=14.04), 53.6% were male, 89.5% were white, 45.9% were employed, and 47.5% had private insurance.

OUTCOME MEASURES

Unplanned 90-day readmissions and 12-month patient-reported outcomes (PROs) including numeric rating scale (NRS) scores for back and leg pain, Oswestry Disability Index (ODI) scores, EuroQol-5 Dimension (EQ-5D) scores, and North American Spine Society (NASS) patient-satisfaction scores.

METHODS

The lumbar module of the QOD was queried for adults undergoing elective lumbar spine surgery for degenerative disease. Unplanned 90-day readmissions were classified into 4 groups: medical, surgical, pain-only, and no readmissions. Medical and surgical readmissions were further categorized into primary reason for readmission. 12-month PROs assessing patient back and leg pain (NRS), disability (ODI), quality of life (EQ-5D), and patient satisfaction were collected. Multivariable models predicting 12-month PROs were built controlling for covariates.

RESULTS

A total of 31,430 patients (94%) had no unplanned readmission while 2,017 patients (6%) had an unplanned readmission within 90 days following lumbar surgery. Patients with readmissions had significantly worse 12-month PROs compared with those with no unplanned readmissions in covariate-adjusted models. Using Wald-df as a measure of predictor importance, surgical readmissions were associated with the worst 12-month outcomes, followed by pain-only, then medical readmissions. In separate covariate adjusted models, we found that readmissions for pain, SSI/wound dehiscence, and revisions were among the most important predictors of worse outcomes at 12-months.

CONCLUSIONS

Unplanned 90-day readmissions were associated with worse pain, disability, quality of life, and greater dissatisfaction at 12-months, with surgical readmissions having the greatest impact, followed by pain-only readmissions, then medical readmissions. Readmissions for pain, SSI/wound dehiscence, and revisions were the most important predictors of worse outcomes. These results may help providers better understand the factors that impact outcomes following lumbar spine surgery and promote improved patient counseling and perioperative management.

Impact of Unplanned Readmission on Patient-Reported Outcomes After Cervical Spine Surgery: A National Study of 13 355 Patients

BACKGROUND AND OBJECTIVES

Although risk factors for unplanned readmission after cervical spine surgery have been widely reported, less is known about how readmission itself affects patient-reported outcome measures (PROMs). Using the Quality Outcomes Database registry of patients undergoing elective cervical spine surgery, we sought to (1) determine the impact of unplanned readmission on PROMs and (2) compare the effect of specific readmission reasons on PROMs.

METHODS

An observational study was performed using a multi-institution, retrospective registry for patients undergoing cervical spine surgery. The occurrence of 90-day unplanned readmission classified into medical, surgical, pain only, and no readmissions was the exposure variable. Outcome variables included 12-month PROMs of Neck Disability Index (NDI), Numeric Rating Scale (NRS)-neck/arm pain, EuroQol-5D (EQ-5D), and patient dissatisfaction. Multivariable models predicting each PROM were built using readmission reasons controlling for demographics, clinical characteristics, and preoperative PROMs.

RESULTS

Data from 13 355 patients undergoing elective cervical spine surgery (82% anterior approach and 18% posterior approach) were analyzed. Unplanned readmission within 90 days of surgery occurred in 3.8% patients, including medical (1.6%), surgical (1.8%), and pain (0.3%). Besides medical reasons, wound infection/dehiscence was the most common reason for unplanned readmission for the total cohort (0.5%), dysphagia in the anterior approach (0.6%), and wound infection/dehiscence in the posterior approach (1.5%). Based on multivariable regression, surgical readmission was significantly associated with worse 12-month NDI, NRS-neck pain, NRS-arm pain, EQ-5D, and higher odds of dissatisfaction. Pain readmissions were associated with worse 12-month NDI and NRS-neck pain scores, and worse dissatisfaction. For specific readmission reasons, pain, surgical site infection/wound dehiscence, hematoma/seroma, revision surgery, deep vein thrombosis, and pulmonary embolism were significantly associated with worsened 12-month PROMs.

CONCLUSION

In patients undergoing elective cervical spine surgery, 90-day unplanned surgical and pain readmissions were associated with worse 12-month PROMs compared with patients with medical readmissions and no readmissions.

Comparing Patient-Reported Outcomes, Complications, Readmissions, and Revisions in Posterior Lumbar Fusion With, Versus Without, an Interbody Device

STUDY DESIGN

Retrospective analysis on prospectively collected data.

OBJECTIVES

To compare posterior lumbar fusions with versus without an interbody in: (1) Patient-reported outcomes (PROs) at 1 year and (2) postoperative complications, readmission, and reoperations.

SUMMARY OF BACKGROUND DATA

Elective lumbar fusion is commonly used to treat various lumbar pathologies. Two common approaches for open posterior lumbar fusion include posterolateral fusion (PLF) alone without an interbody and with an interbody through techniques, like transforaminal lumbar interbody fusion. Whether fusion with or without an interbody leads to better outcomes remains an area of active research.

PATIENTS AND METHODS

The Lumbar Module of the Quality Outcomes Database was queried for adults undergoing elective primary posterior lumbar fusion with or without an interbody. Covariates included demographic variables, comorbidities, primary spine diagnosis, operative variables, and baseline PROs, including Oswestry Disability Index, North American Spine Society satisfaction index, numeric rating scale-back/leg pain, and Euroqol 5-dimension. Outcomes included complications, reoperations, readmissions, return to work/activities, and PROs. Propensity score matching and linear regression modeling were used to estimate the average treatment effect on the treated to assess the impact of interbody use on patient outcomes.

RESULTS

After propensity matching, there were 1044 patients with interbody and 215 patients undergoing PLF. The average treatment effect on the treated analysis showed that having an interbody or not had no significant impact on any outcome of interest, including 30-day complications and reoperations, 3-month readmissions, 12-month return to work, and 12-month PROs.

CONCLUSION

There were no discernible differences in outcomes between patients undergoing PLF alone versus with an interbody in elective posterior lumbar fusion. These results add to the growing body of evidence that posterior lumbar fusions with and without an interbody seem to have similar outcomes up to 1 year postoperatively when treating degenerative lumbar spine conditions.

Determining the Effect of Intraoperative TXA on Postoperative Blood Loss in ACDF

STUDY DESIGN

Retrospective cohort study using prospectively collected data.

OBJECTIVE

To determine the effectiveness of intraoperative tranexamic acid (TXA) in anterior cervical discectomy and fusion (ACDF) on postoperative blood loss.

SUMMARY OF BACKGROUND DATA

TXA has been proven to be a safe and effective agent in reducing blood loss after cervical surgery; however, its efficacy when used intraoperatively for ACDF surgeries had yet to be researched. Currently, there are few studies examining the effects of intraoperative TXA in cervical spinal fusion, and none specifically examining TXA use in ACDF.

METHODS

A tertiary medical center's prospectively collected spine registry was queried between 1/1/18 and 12/1/21 for all patients who underwent elective ACDF surgery and received a drain postoperatively. Patients were separated into 2 groups; those who had received intraoperative TXA and those who did not. Baseline demographic and operative variables were collected from the registry. The primary outcome was postoperative blood loss over a 24-hour period. Secondary outcomes included total drain output, intraoperative estimated blood loss, operative duration, drain duration, changes in preoperative to postoperative hemoglobin and hematocrit levels, and rate of transfusions, complications, revisions, and reoperations. Univariate and multivariate regression analyses were performed.

RESULTS

Two hundred eighty-six patients were included. One hundred ninety patients underwent ACDF and did not receive intraoperative TXA, whereas 96 patients underwent ACDF and did receive TXA. There were no differences in any demographic or baseline variables. Multivariate analysis showed intraoperative TXA was associated with shorter drain duration (β=-5.74, 95% CI: -10.9 to -0.53, P =0.031) and reduction in 24-hour drain output (β=-12.2, 95% CI: -19.4 to -4.89, P =0.001) and total drain output (β=-14.0, 95% CI: -22.9 to -5.05, P =0.002).

CONCLUSIONS

TXA use during ACDF procedures leads to a decrease in perioperative blood loss and faster drain removal. TXA is an effective and safe agent for reducing perioperative blood loss in ACDF surgery.

LEVEL OF EVIDENCE

III.

Implant Surface Technologies to Promote Spinal Fusion: A Narrative Review

The technology surrounding spinal fusion surgery has continuously evolved in tandem with advancements made in bioengineering. Over the past several decades, developments in biomechanics, surgical techniques, and materials science have expanded innovation in the spinal implant industry. This narrative review explores the current state of implant surface technologies utilized in spinal fusion surgery. This review covers various types of implant surface materials, focusing on interbody spacers composed of modified titanium, polyetheretherketone, hydroxyapatite, and other materials, as well as pedicle screw surface modifications. Advantages and disadvantages of the different surface materials are discussed, including their biocompatibility, mechanical properties, and radiographic visibility. In addition, this review examines the role of surface modifications in enhancing osseointegration and reducing implant-related complications and, hopefully, improving patient outcomes. The findings suggest that while each material has its potential advantages, further research is needed to determine the optimal surface properties for enhancing spinal fusion outcomes.

L1-pelvic angle: a convenient measurement to attain optimal deformity correction

PURPOSE

(1) Evaluate the associations between L1-pelvic angle (L1PA) and both sagittal vertical axis (SVA) and T1-pelvic angle (T1PA), and (2) assess the clinical impact of L1PA.

METHODS

A single-institution retrospective cohort study was undertaken for patients undergoing adult spinal deformity (ASD) surgery from 2013 to 2017. Ideal L1PA was defined as (0.5xPelvic Incidence)-21. Pearson correlation was performed to compare L1PA, SVA, and T1PA. Univariate/multivariate regression was performed to assess the effect of L1PA on mechanical complications, controlling for age, BMI, and postoperative pelvic incidence-lumbar lordosis mismatch (PI/LL). Due to the overlapping nature of patients with pseudarthrosis and rod fracture, these patients were analyzed together.

RESULTS

A total of 145 patients were included. Mean preoperative L1PA, SVA, and T1PA were 15.5 ± 8.9°, 90.7 ± 66.8 mm, and 27.1 ± 13.0°, respectively. Mean postoperative L1PA, SVA, and T1PA were 15.0 ± 8.9°, 66.7 ± 52.8 mm, and 22.3 ± 11.1°, respectively. Thirty-six (24.8%) patients achieved ideal L1PA. Though the correlation was modest, preoperative L1PA was linearly correlated with preoperative SVA (r2 = 0.16, r = 0.40, 95%CI = 0.22-0.60, p < 0.001) and T1PA (r2 = 0.41, r = 0.62, 95%CI = 0.46-0.76, p < 0.001). Postoperative L1PA was linearly correlated with postoperative SVA (r2 = 0.12, r = 0.37, 95%CI = 0.18-0.56, p < 0.001) and T1PA (r2 = 0.40, r = 0.62, 95%CI = 0.45-0.74, p < 0.001). Achieving ideal L1PA ± 5° was associated with a decreased risk of rod fracture/pseudarthrosis on univariate and multivariate regression (OR = 0.33, 95%CI = 0.12-0.86, p = 0.024). No association between achieving ideal L1PA and patient-reported outcomes was observed.

CONCLUSION

L1PA was modestly correlated with SVA and T1PA, and achieving ideal L1PA was associated with lower rates of rod fracture/pseudarthrosis. Future studies are warranted to better define the clinical implications of achieving a normal L1PA.

LEVEL OF EVIDENCE

III.

Clinical and radiographic outcomes following correction of idiopathic scoliosis in adolescence vs young adulthood

PURPOSE

The natural history of adolescent idiopathic scoliosis (AIS) has been well documented, but the impact of age at the time of surgical correction is relatively understudied. In this study, we matched patients undergoing surgical correction of adult idiopathic scoliosis (AdIS) with a cohort of AIS patients to compare: (1) coronal and sagittal radiographic correction, (2) operative variables, and (3) postoperative complications.

METHODS

A single-institution scoliosis registry was queried for patients undergoing idiopathic scoliosis surgery from 2000-2017.

INCLUSION CRITERIA

patients with idiopathic scoliosis, no previous spine surgery, and 2-year follow-up. AdIS patients were matched 1:2 with AIS patients based on Lenke classification and curve characteristics. Independent sample t-test and Chi-square test was used to analyze the data.

RESULTS

31 adults underwent surgical correction of idiopathic scoliosis and were matched with 62 adolescents. Mean age of adults was 26.2 ± 11.05, mean BMI was 25.6 ± 6.0, and 22 (71.0%) were female. Mean age of adolescents was 14.2 ± 1.8, mean BMI was 22.7 ± 5.7, and 41(66.7%) were female. AdIS had significantly less postoperative major Cobb correction (63.9% vs 71.3%, p = 0.006) and final major Cobb correction (60.6% vs 67.9%, p = 0.025). AdIS also had significantly greater postoperative T1PA (11.8 vs 5.8, p = 0.002). AdIS had longer operative times (p = 0.003), higher amounts of pRBCs transfused (p = 0.005), longer LOS (p = 0.016), more ICU requirement (p = 0.013), higher overall complications (p < 0.001), higher rate of pseudarthrosis (p = 0.026), and more neurologic complications (p = 0.013).

CONCLUSION

Adult patients undergoing surgical correction of idiopathic scoliosis had significantly worse postoperative coronal and sagittal alignment when compared with adolescent patients. Adult patients also had higher rates of complications, longer operative times, and longer hospital stays.

LEVEL OF EVIDENCE

III.

Case Report-Traumatic L5-S1 Instability: Are Upright Radiographs Potentially Dangerous?

BACKGROUND

Traumatic lumbosacral instability is a rare but potentially devastating injury. These injuries are frequently associated with neurologic injury and often result in long-term disability. Despite their severity, radiographic findings can be subtle, and multiple reports exist in which these injuries were not recognized on initial imaging. Transverse process fractures, high-energy mechanisms, and other injury features have been suggested as indications for advanced imaging, which has a high degree of sensitivity in detecting unstable injuries.

CASE PRESENTATION

A 21-year-old man presented to our level I trauma center after being ejected in a rollover motor vehicle collision. He sustained multiple injuries, including multiple lumbar transverse process fractures and a unilateral superior articular facet fracture of S1.

PRIMARY OUTCOMES

Initial supine computed tomography (CT) images showed no displacement of the fracture and no listhesis or instability. Subsequent upright imaging in a brace, however, demonstrated significant displacement of the fracture with dislocation of the contralateral L5-S1 facet joint and significant anterolisthesis. The patient underwent open posterior reduction and stabilization of L4-S1 followed by L5-S1 anterior lumbar interbody fusion. The patient demonstrated excellent alignment on postoperative imaging. At 3 months postoperatively, he had returned to work, was ambulating without assistance, and reported minimal back discomfort and no lower extremity pain, numbness, or weakness.

CONCLUSION

This case serves as a warning that supine CT imaging alone may not be sufficient to rule out unstable lumbar spine injuries, such as traumatic L5-S1 instability, and that upright radiographs in these potentially unstable injuries may represent a hazard to patients. Fractures involving the pedicle, pars, or facet joints as well as multiple transverse process fractures and/or a high-energy mechanism of injury should all raise suspicion of instability and warrant additional imaging.

CLINICAL RELEVANCE

This article provides guidance on approaching treatment for patients with potential traumatic lumbosacral instability.

LEVEL OF EVIDENCE: 5

Interleukin-34 Permits Porphyromonas gingivalis Survival and NF-κB p65 Inhibition in Macrophages

Interleukin-34 (IL-34) is a cytokine that supports the viability and differentiation of macrophages. An important cytokine for the development of epidermal immunity, IL-34 is present and plays a role in the immunity of the oral environment. IL-34 has been linked to inflammatory periodontal diseases, which involve innate phagocytes, including macrophages. Whether IL-34 can alter the ability of macrophages to effectively interact with oral microbes is currently unclear. Using macrophages derived from human blood monocytes with either the canonical cytokine colony-stimulating factor (CSF)1 or IL-34, we compared the ability of the macrophages to phagocytose, kill, and respond through the production of cytokines to the periodontal keystone pathogen Porphyromonas gingivalis. While macrophages derived from both cytokines were able to engulf the bacterium equally, IL-34 derived macrophages were much less capable of killing internalized P. gingivalis. Of the macrophage cell surface receptors known to interact with P. gingivalis, DC-SIGN was found to have the largest variation between IL-34 and CSF1-derived macrophages. We also found that upon interaction with P. gingivalis, IL-34 derived macrophages produced significantly less of the neutrophil chemotactic factor IL-8 than macrophages derived in the presence of CSF1. Mechanistically, we identified that levels of IL-8 corresponded with P. gingivalis survival and dephosphorylation of the major transcription factor NF-κB p65. Overall, we found that macrophages differentiated in the presence of IL-34, a dominant cytokine in the oral gingiva, have a reduced ability to kill the keystone pathogen P. gingivalis and may be susceptible to specific bacteria-mediated cytokine modification. This article is protected by copyright. All rights reserved.

Adipose-targeted overexpression of mitochondrial-targeted catalase does not improve cardio-metabolic parameters in mice with diet-induced obesity

Background

Obesity is associated with significant cardio-metabolic complications. Adipokines, and cytokines released from adipose tissue (AT) stimulate excessive mitochondrial production of reactive oxygen species (ROS). ROS-mediated oxidative modifications is associated with development of insulin resistance and impaired cardiac function. We hypothesised that adipose-targeted overexpression of mitochondrial-targeted catalase (AT-mCAT) could lead to improvement in diet-induced cardio-metabolic dysfunction.

Methods/Results

mCAT (floxed) and AdipoQ-Cre mice were crossed to generate mice overexpressing catalase with a mitochondrial-targeting sequence predominantly in AT (AT-mCAT). Wild-type (WT) and AT-mCAT male mice were fed normal chow (NC) or high-fat/high-sucrose (HFHS) diet (36%fat/34%sucrose) for 4 months. At endpoint, echocardiography showed reduced cardiac output in all groups v WT NC (p&lt;0.05); reduced IVSd in AT-mCAT NC and HFHS groups v WT NC (p&lt;0.01); reduced left ventricular ejection fraction in AT-mCAT HFHS v WT NC (p&lt;0.05) and no differences in fractional shortening or E/A ratio between groups. Glucose tolerance tests (2g/kg) showed impairment in WT HFHS and AT-mCAT HFHS v WT NC (p&lt;0.01, p&lt;0.05 respectively). Triglyceride levels were increased in WT HFHS and AT-mCAT HFHS v WT NC (p&lt;0.05). Analysis of hypertrophic signalling in cardiac tissues by ELISA showed p-AKT/total Akt levels were decreased in AT-mCAT hearts regardless of diet (WT NC v AT-mCAT NC p&lt;0.01; WT HFHS v AT-mCAT HFHS p&lt;0.05).

Conclusion

Our results confirm previous findings that diet-induced obesity is a systemic condition. Targeting adipose tissue with mitochondrial catalase may not be adequate to prevent development of cardio-metabolic dysfunction. More systemic approaches may be required to combat obesity-induced cardio-metabolic impairment.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart Foundation of Australia