Negative pressure wound therapy in spinal fusion patients.

Post-operative wound complications are some of the most common acute complications following spine surgery. These surgical site infections (SSI) contribute to increased healthcare related costs. Negative pressure wound therapy (NPWT) has long been used for treatment of soft tissue injury or defects. NPWT may reduce the incident of SSI following spinal fusion procedures; however, its potential applications need further clarification. Thus, we conducted a retrospective analysis of two cohorts to compare NPWT to traditional sterile dressings following spinal fusions in regards to post-operative outcomes. Following institutional review board approval, 42 patients who had a NPWT were matched by type of surgery to 42 patients who had traditional dressings. A retrospective chart-review was completed. Outcome measures, particularly SSI and need for reoperation, were analyzed using one-way ANOVA for both univariate and multivariate analysis. When controlled for sex and body-mass index, the use of a NPWT was independently correlated with decreased SSI (P = .035). Superficial dehiscence, seroma, need for additional outpatient care, and need for operative revision were all found to occur at higher rates in the traditional dressing cohort. Closed incisional negative pressure wound therapy provides a cost-effective method of decreasing surgical site infection for posterior elective spine surgeries.

Catenin delta-1 (CTNND1) phosphorylation controls the mesenchymal to epithelial transition in astrocytic tumors.

Inactivating mutations of the TSC1/TSC2 complex (TSC1/2) cause tuberous sclerosis (TSC), a hereditary syndrome with neurological symptoms and benign hamartoma tumours in the brain. Since TSC effectors are largely unknown in the human brain, TSC patient cortical tubers were used to uncover hyperphosphorylation unique to TSC primary astrocytes, the cell type affected in the brain. We found abnormal hyperphosphorylation of catenin delta-1 S268, which was reversible by mTOR-specific inhibitors. In contrast, in three metastatic astrocytoma cell lines, S268 was under phosphorylated, suggesting S268 phosphorylation controls metastasis. TSC astrocytes appeared epithelial (i.e. tightly adherent, less motile, and epithelial (E)-cadherin positive), whereas wild-type astrocytes were mesenchymal (i.e. E-cadherin negative and highly motile). Despite their epithelial phenotype, TSC astrocytes outgrew contact inhibition, and monolayers sporadically generated tuberous foci, a phenotype blocked by the mTOR inhibitor, Torin1. Also, mTOR-regulated phosphokinase C epsilon (PKCe) activity induced phosphorylation of catenin delta-1 S268, which in turn mediated cell-cell adhesion in astrocytes. The mTOR-dependent, epithelial phenotype of TSC astrocytes suggests TSC1/2 and mTOR tune the phosphorylation level of catenin delta-1 by controlling PKCe activity, thereby regulating the mesenchymal-epithelial-transition (MET). Thus, some forms of TSC could be treated with PKCe inhibitors, while metastasis of astrocytomas might be blocked by PKCe stimulators.

Heterogeneity within the PF-EPN-B ependymoma subgroup.

Posterior fossa ependymoma comprise three distinct molecular variants, termed PF-EPN-A (PFA), PF-EPN-B (PFB), and PF-EPN-SE (subependymoma). Clinically, they are very disparate and PFB tumors are currently being considered for a trial of radiation avoidance. However, to move forward, unraveling the heterogeneity within PFB would be highly desirable. To discern the molecular heterogeneity within PFB, we performed an integrated analysis consisting of DNA methylation profiling, copy-number profiling, gene expression profiling, and clinical correlation across a cohort of 212 primary posterior fossa PFB tumors. Unsupervised spectral clustering and t-SNE analysis of genome-wide methylation data revealed five distinct subtypes of PFB tumors, termed PFB1-5, with distinct demographics, copy-number alterations, and gene expression profiles. All PFB subtypes were distinct from PFA and posterior fossa subependymomas. Of the five subtypes, PFB4 and PFB5 are more discrete, consisting of younger and older patients, respectively, with a strong female-gender enrichment in PFB5 (age: p = 0.011, gender: p = 0.04). Broad copy-number aberrations were common; however, many events such as chromosome 2 loss, 5 gain, and 17 loss were enriched in specific subtypes and 1q gain was enriched in PFB1. Late relapses were common across all five subtypes, but deaths were uncommon and present in only two subtypes (PFB1 and PFB3). Unlike the case in PFA ependymoma, 1q gain was not a robust marker of poor progression-free survival; however, chromosome 13q loss may represent a novel marker for risk stratification across the spectrum of PFB subtypes. Similar to PFA ependymoma, there exists a significant intertumoral heterogeneity within PFB, with distinct molecular subtypes identified. Even when accounting for this heterogeneity, extent of resection remains the strongest predictor of poor outcome. However, this biological heterogeneity must be accounted for in future preclinical modeling and personalized therapies.

Impalement brain injury from steel rod causing injury to jugular bulb: case report and review of the literature.

BACKGROUND: The management of impalement penetrating brain injuries (IPBI) from non-missile objects is extremely challenging, especially when vascular structures are involved. Cerebral angiography is a crucial tool in initial evaluation to assess for vascular injury as standard non-invasive imaging modalities are limited by foreign body artifact, especially for metallic objects. CASE STUDY: This study reports a case of an IPBI caused by a segment of steel rebar resulting in injury to the left jugular bulb and posterior temporal lobe. It describes the initial presentation, radiology, management and outcome in this patient and reviews the literature of similar injuries.

A novel technique for decortication of the lumbar facet joints for posterolateral fusion with percutaneous exposure: A cadaveric feasibility study.

Background: Percutaneous approaches to the spine have been explored recently for various procedures, including transforaminal lumbar interbody fusion. It is known that facet decortication leads to higher rates of fusion, but effective percutaneous approaches have not been well documented. There are a set of instruments used in the cervical spine for percutaneous decortication, the CORUS™ Spinal System-X (DI# 00852776006508), which may be useful in this setting. Our aim was to investigate the feasibility of decorticating the lumbar facet joints with these instruments in cadavers to aid in minimally invasive lumbar fusion. Methods: We performed percutaneous facet joint decortication at each facet joint in the lumbar spine in two adult cadavers. We tested varying degrees of laterality for entry points and angulation for access at each level to optimize the innovative procedure. Results: When using the CORUS™ Spinal System-X to obtain percutaneous access for facet decortication in the lumbar spine, we successfully dissected down to the facet joint without neurovascular injury. At the L1-L2 and L2-L3 levels, access was best obtained at 4 cm from midline with an angulation of 10°. At the L3-L4 and L4-L5 level, access was best obtained at 4 cm from midline with an angulation of 20°. Conclusions: This study demonstrates that percutaneous lumbar facet joint decortication is feasible with the CORUS™ Spinal System-X instruments, and warrants further, comparative study in the clinical setting.

Impact of obesity on adult spinal deformity (ASD) long-segment spinal fusion radiographic and clinical outcomes.

STUDY DESIGN: Retrospective chart review of patients receiving long-segment fusion during a five-year period. OBJECTIVE: To determine whether obese patients receive comparable benefits when receiving long-segment fusion compared to non-obese patients and to identify factors that may predict hardware failure and post-surgical complications among obese patients. METHODS: Demographic, spinopelvic radiographic, patient-reported outcome measures (PROMs), and complications data was retrospectively collected from 120 patients who underwent long-segment fusion during a five-year period at one tertiary care medical center. Radiographic measurements were pelvic incidence, pelvic tilt (PT), lumbar lordosis, L4-S1 lordosis, thoracic kyphosis, sagittal vertical axis, PI-LL mismatch, and proximal junction cobb angle at upper instrumented vertebrae + 2 (UIV+2). PROMs were Oswestry disability index, numeric rating scale (NRS) Back Pain, NRS Leg Pain, RAND SF-36 pain, and RAND SF-36 physical functioning. Included patients were adults and had at least 2-years of postoperative follow-up. Descriptive and multivariate statistical analysis was performed with α = 0.05. RESULTS: Patients with a BMI ≥ 30 (n=63) and patients with a BMI < 30 (n=57) demonstrated comparable improvements (P>0.05) for all spinopelvic radiographic measurements and PROMs. Each cohort demonstrated significant improvements from pre-assessment to post-assessment on nearly all spinopelvic radiographic measurements and PROMs (P<0.05), except PT and L4-S1 lordosis where neither group improved (p=0.95 and 0.58 for PT and P=0.23 and 0.11 for L4-S1 lordosis fornon-obese and obese cohorts respectively) and SF-36 physical functioning where the non-obese cohort not statistically improve (P=0.08). Patients with a BMI ≥ 30 demonstrated an increased incidence of cardiovascular complications (P=0.0293), acute kidney injury (P=0.0241), rod fractures (P=0.0293), and reoperations (P=0.0241) when compared to patients with a BMI < 30. CONCLUSION: This study adds to a growing body of evidence linking demographic factors with risks of hardware failure. Further, this data challenges the assumption that obese patients may not receive sufficient benefit to be long-segment surgical candidates. However, given their elevated risk for post-operative and delayed hardware complications, obese patients should be appropriately counseling before undergoing surgery.

Decompression Alone Versus Interspinous/Interlaminar Device Placement for Degenerative Lumbar Pathologies: Systematic Review and Meta-Analysis.

INTRODUCTION: Interspinous devices (ISDs) and interlaminar devices (ILDs) are marketed as alternatives to conventional surgery for degenerative lumbar conditions; comparisons with decompression alone are limited. The present study reviews the extant literature comparing the cost and effectiveness of ISDs/ILDs with decompression alone. METHODS: Articles comparing decompression alone with ISD/ILD were identified; outcomes of interest included general and disease-specific patient-reported outcomes, perioperative complications, and total treatment costs. Outcomes were analyzed at <6 weeks, 3 months, 6 months, 1 year, 2 years, and last follow-up. Analyses were performed using random effects modeling. RESULTS: Twenty-nine studies were included in the final analysis. ILD/ISD showed greater leg pain improvement at 3 months (mean difference, -1.43; 95% confidence interval, [-1.78, -1.07]; P < 0.001), 6 months (-0.89; [-1.55, -0.24]; P = 0.008), and 12 months (-0.97; [-1.25, -0.68]; P < 0.001), but not 2 years (P = 0.22) or last follow-up (P = 0.09). Back pain improvement was better after ISD/ILD only at 1 year (-0.87; [-1.62, -0.13]; P = 0.02). Short-Form 36 physical component scores or Zurich Claudication Questionnaire (ZCQ) symptom severity scores did not differ between the groups. ZCQ physical function scores improved more after decompression alone at 6 months (0.35; [0.07, 0.63]; P = 0.01) and 12 months (0.23; [0.00, 0.46]; P = 0.05). Oswestry Disability Index and EuroQoL 5 dimensions scores favored ILD/ISD at all time points except 6 months (P = 0.07). Reoperations (odds ratio, 1.75; [1.23, 2.48]; P = 0.002) and total care costs (standardized mean difference, 1.19; [0.62, 1.77]; P < 0.001) were higher in the ILD/ISD group; complications did not differ significantly between the groups (P = 0.41). CONCLUSIONS: Patient-reported outcomes are similar after decompression alone and ILD/ISD; the observed differences do not reach accepted minimum clinically important difference thresholds. ISD/ILDs have higher associated costs and reoperation rates, suggesting current evidence does not support ILD/ISDs as a cost-effective alternative to decompression alone.

Use of global sagittal flexibility to predict proximal junctional kyphosis after spinal deformity surgery.

OBJECTIVE: Sagittal alignment is an important predictor of functional outcomes after surgery for adult spinal deformity (ASD). A rigid spinal column may create a large lever arm that may impact the rate of proximal junctional kyphosis (PJK) after ASD surgery. In this study, the authors sought to determine whether relatively low preoperative global spinal flexibility (i.e., rigid spine) predicts increased incidence of PJK at 1 year after ASD surgery. METHODS: The authors retrospectively reviewed long-segment thoracolumbar fusions with pelvic fixation performed at a single tertiary care center between October 2015 and September 2020 in patients with a minimum of 1-year radiographic and clinical follow-up. Two cohorts were established on the basis of the optimal value for spinal flexibility, as defined by the absolute difference between the preoperative standing and supine C7 sagittal vertical axes, which the authors termed global sagittal flexibility (GSF). Demographic information, radiographs, various associated complications, and patient-reported outcome measures (PROMs) were analyzed. RESULTS: Eighty-five patients met the inclusion criteria. Receiver operating characteristic (ROC) analysis using GSF to predict an increase in the proximal junctional sagittal Cobb angle (PJCA) greater than or equal to 10° at 1-year follow-up provided an area under the curve of 0.64 and identified an optimal GSF threshold value of 3.7 cm. Patients with GSF > 3.7 cm were considered globally flexible (48 patients), and those with GSF ≤ 3.7 cm were classified as rigid (37 patients). Rigid patients were noted to have a significantly higher risk of ΔPJCA ≥ 10° at 1-year follow-up (51.4% vs 29.3%, p = 0.049). No changes in the reoperation rates or PROMs based on GSF were observed in the 1- or 2-year postoperative window. CONCLUSIONS: Based on these retrospective data, preoperative global spinal rigidity portends an independently elevated risk for the development of PJK after ASD surgery. No differences in other complication rates or PROMs data were observed between groups. Data collection was limited to a 2-year postoperative window; therefore, longer follow-up is required to further elucidate the relationship between rigidity and reoperation rates. Based on these retrospective data, flexibility may influence the outcomes of patients with ASD.

CT guided biopsy for osteodiscitis reduces cost of hospitalization in the landscape of increasing intravenous drug use: A single center retrospective analysis.

OBJECTIVE: Osteodiscitis has been demonstrated to show significant morbidity and mortality. Cultures and CT guided biopsy (CTB) are commonly used diagnosis of osteodiscitis. This study's purpose is to evaluate the cost burden of CTB and to evaluate how IVDU affects patient management in the setting of osteodiscitis. METHODS: Patients admitted for osteodiscitis from 2011-2021 were retrospectively reviewed and stratified into cohorts by CTB status. Additional cohorts were stratified by Intravenous Drug Use (IVDU). Patient demographics, total cost of hospitalization, length of hospitalization, time to biopsy, IVDU status, and other factors were recorded. T-Test, Chi-squared analysis, and ANOVA were used for statistical analysis. RESULTS: Total cost of hospitalization was recorded for 140 patients without CTB and 346 patients with CTB. Average cost of hospitalization for non-CTB was $227,317.86 compared to CTB at $119,799.20 (p < 0.001). Length of stay (LOS) was found to be 18.01 days for non-CTB and 14.07 days for CTB patients (0.00282). When stratified by days until biopsy, patients who had CTB sooner, had significantly reduced cost of hospitalization (p = 0.0003). Patients with IVDU history were significantly younger (p < 0.001) with lower BMI (p < 0.001) and a significantly different clinical profile. There was a significant difference in positive open biopsy when separated by IVDU status (p = 0.025). CONCLUSION: CTB was associated with significantly reduced cost of hospitalization and LOS compared to non-CTB. IVDU patients with osteodiscitis have significantly different clinical profiles than non-IVDU that may impact diagnosis and treatment. Further work is indicated to elucidate causes of these differences to provide high value care to patients with osteodiscitis.

Flexion-distraction injuries of the thoracolumbar spine: open fusion versus percutaneous pedicle screw fixation.

OBJECT: Flexion-distraction injuries occur due to distractive forces causing disruption of the posterior and middle spinal columns. These fractures classically consist of a fracture line through the posterior bony elements; involvement of the posterior ligamentous complex is, however, common. Surgical treatment is often required for these unstable injuries to avoid neurological deterioration and posttraumatic kyphosis, and the surgery traditionally consists of an open posterior approach with instrumented fusion. Percutaneous pedicle screw fixation for these injuries, with the goal of minimal tissue disruption and preservation of normal anatomy while achieving adequate stabilization, has recently been reported in the literature, but to date, a direct comparative study comparing open and percutaneous fixation has not been reported. The authors report their experience treating these fractures with both techniques and review the available literature. METHODS: Patients with flexion-distraction injury who were treated between May 2003 and March 2013 were prospectively followed. American Spinal Injury Association scores and degree of kyphotic angulation were recorded at admission, discharge, and follow-up. Data regarding intraoperative blood loss and operative time were obtained from a chart review. Patients treated with open versus minimally invasive procedures were compared. RESULTS: The authors identified 39 patients who suffered flexion-distraction injuries and were treated at their institution during the specified period; one of these patients declined surgery. All had injury to the posterior ligamentous complex. Open surgical procedures with pedicle screw fixation and posterolateral fusion were performed in 27 patients, while 11 patients underwent minimally invasive pedicle screw placement. Overall, there was improvement in kyphotic angulation at the time of discharge as well as most recent follow-up in both the open surgery and minimally invasive surgery (MIS) groups. The authors found no significant difference in American Spinal Injury Association score or the degree of kyphotic angulation between the MIS and open surgery groups. There was a trend toward shorter operative time for the MIS group, and patients who underwent minimally invasive procedures had significantly less blood loss. CONCLUSIONS: Minimally invasive percutaneous pedicle screw fixation appears to have similar efficacy in the treatment of flexion-distraction injuries and it allows for reduced blood loss and tissue damage compared with open surgical techniques. Therefore it should be considered as an option for the treatment of this type of injury.

Delayed stenosis associated with sublaminar band placement in the thoracic spine for proximal junctional kyphosis.

Background: Proximal junctional thoracic kyphosis (PJK) is common following adult spinal deformity (ASD) surgery and may require revision operations. In this case series, we present delayed complications associated with the use of sublaminar banding (SLBs) for PJK prophylaxis. Case Description: Three patients underwent long-segment thoracolumbar decompression and fusions for ASD. All had undergone SLB placement for PJK prophylaxis. All three subsequently developed neurologic complications secondary to cephalad spinal cord compression/stenosis requiring urgent revision surgery. Conclusion: The placement of SLBs placed to prevent PJK may lead to sublaminar inflammation contributing to severe cephalad spinal canal stenosis and myelopathy following ASD surgery. Surgeons should be aware of this potential complication and may consider alternatives to SLB placement to avoid this complication.

Endoscopic endonasal resection of craniovertebral junction osteomyelitis: illustrative cases.

BACKGROUND: Operative management of craniovertebral junction (CVJ) osteomyelitis has traditionally been extracranial and focused on debriding the infection. In select patients, the endoscopic endonasal approach (EEA) with a focus on additional resection versus debridement may be preferred. The goal of this study is to present the authors' experience with the EEA with gross or subtotal resection for the treatment of osteomyelitis at the CVJ and describe their technique in the context of the literature. OBSERVATIONS: Two patients of the authors' and 6 detailed case reports in the literature were identified with a mean age of 58.9 years. Most patients (n = 5; 62.5%) underwent skull base surgery and debridement (n = 5; 62.5%). Although more common, debridement was inferior to resection in terms of neurological improvement (66.7% vs. 100.0%) postoperatively. The majority (n = 7; 87.5%) of patients underwent occipitocervical fusion. LESSONS: Osteomyelitis is an exceedingly rare lesion of the CVJ. Despite the region's delicate biomechanical stability, resection of infected bone may be superior to debridement alone in terms of clinical outcome. Given how well established the safety of the EEA is to this region, further study of outcomes with resection is warranted.

Early Postural Stability Changes in Patients Undergoing Correction of Spinal Deformity: A Prospective, Controlled Pilot Study.

BACKGROUND CONTEXT: Adult spinal deformity (ASD) is a prevalent condition often requiring surgical intervention. Improved outcomes among ASD patients have been shown to correlate with postoperative spinopelvic parameters, yet little is currently known about the role of postural stability and balance assessment for ASD patients. PURPOSE: Explore early changes in postural stability following ASD correction. STUDY DESIGN: Prospective cohort study. PATIENT SAMPLE: Sixteen adult patients who underwent four-level or greater posterolateral fusion to address global spinal malalignment and 14 healthy controls with no known spinal deformity nor surgery. OUTCOME MEASURES: Postural stability parameters, spinopelvic parameters preoperatively and postoperatively. METHODS: Force plate balance assessment was completed where participants and healthy controls were instructed to stand with their hands at their sides, standing still, with eyes open. Center of pressure (COP), center of gravity (COG), and cone of economy (COE) parameters were analyzed with paired and unpaired t tests with an alpha of 0.05. RESULTS: Preoperatively, ASD patients demonstrated more COG (P=0.0244) and sagittal and coronal head (P<0.05) sway than healthy controls. Postoperatively, ASD patients exhibited less COP (P=0.0308), COG (P=0.0276) and head (P=0.0345) sway. Compared to healthy controls, ASD patients postoperatively exhibited similar postural stability, aside from COP and COG sway amplitudes (P<0.05), and coronal head sway (P=0.0309). Pelvic incidence-lumbar lordosis and sagittal vertical axis improved from 16.2° to 4.8° (P<0.01) and 82.2 to 22.5 mm (P<0.01), respectively. CONCLUSION: We report a novel early improvement in postural stability, comparable to healthy controls, following ASD correction that may be related to improved spinopelvic alignment. Force plate evaluation may be a useful tool for ASD patients postoperatively. Future clinical trials assessing the impact of postural stability on clinical and radiographic outcomes are warranted.

The Effects of Nicotine- and Cigarette-Related Products on Osteogenesis, Bone Formation, and Bone Mineralization: A Systematic Review.

BACKGROUND: Many clinicians associate nicotine as the causative agent in the negative and deleterious effects of smoking on bone growth and spine fusion. Although nicotine is the primary driver of physiological addiction in smoking, isolated and controlled use of nicotine is one of the most effective adjuncts to quitting smoking. OBJECTIVE: To explore the relationship between nicotine and noncombustion cigarette products on bone growth. METHODS: One thousand five studies were identified, of which 501 studies were excluded, leaving 504 studies available for review. Of note, 52 studies were deemed to be irrelevant. Four hundred fifty-two studies remained for eligibility assessment. Of the remaining 452, 218 failed to assess study outcomes, 169 failed to assess bone biology, 13 assessed 5 patients or fewer, and 12 were deemed to be ineligible of the study criteria. Forty studies remained for inclusion within this systematic review. RESULTS: Of the 40 studies identified for inclusion within the study, 30 studies were classified as "Animal Basic Science," whereas the remaining 10 were categorized as "Human Basic Science." Of the 40 studies, 11 noted decreased cell proliferation and boney growth, whereas 8 showed an increase. Four studies noted an increase in gene expression products, whereas 11 noted a significant decrease. CONCLUSION: The results of this study demonstrate that nicotine has a variety of complex interactions on osteoblast and osteoclastic activities. Nicotine demonstrates dose-dependent effects on osteoblast proliferation, boney growth, and gene expression. Further study is warranted to extrapolate the effects of solitary nicotine on clinical outcomes.

Predicting the Need for Surgery in Patients with Lumbar Disc Herniation: A New Internally Validated Scoring System.

STUDY DESIGN: Prospective study. PURPOSE: To propose a scoring system for predicting the need for surgery in patients with lumbar disc herniation (LDH). OVERVIEW OF LITERATURE: The indications for surgery in patients with LDH are well established. However, the exact timing of surgery is not. According to surgeons, patients with failed conservative treatment who underwent delayed surgery, often after 6 months postsymptom initiation, have poor functional recovery and outcome. METHODS: The current study included patients with symptomatic LDH. Patients with an indication for emergent surgery such as profound or progressive motor deficit, cauda equina syndrome, and diagnoses other than single-level LDH were excluded from the analysis. All patients followed a conservative treatment regimen (a combination of physical therapy, pain medications, and/or spinal epidural steroid injections). Surgery was indicated for patients who continuously experienced pain despite maximal conservative therapy. RESULTS: In total, 134 patients met the inclusion and exclusion criteria. Among them, 108 (80.6%) responded to conservative management, and 26 (19.4%) underwent unilateral laminotomy and microdiscectomy. The symptom duration, disc degeneration grade on magnetic resonance imaging (Pfirrmann disc grade), herniated disc location and type, fragment size, and thecal sac diameter significantly differed between patients who responded to conservative treatment and those requiring surgery. The area under the receiver operating characteristic curve of the scoring system based on the anteroposterior size of the herniated disc fragment and herniated disc location and type was 0.81. CONCLUSIONS: A scoring system based on herniated disc/fragment size, location, and type can be applied to predict the need for surgery in patients with LDH. In the future, this tool can be used to prevent unnecessarily prolonged conservative management (>4-8 weeks).

Electronic versus paper patient-reported outcome measure compliance rates: A retrospective analysis.

OBJECTIVE: Patient-reported outcome measures (PROMs) are key tools used to inform clinical research and patient-centered care. Application of data collected from PROMs, however, may be limited by incomplete responses, and little is known regarding the efficacy of varied PROM delivery methods. The objective of this study was to compare PROMs compliance when delivered via paper and electronic formats. METHODS: Elective adult spinal deformity patients were screened for inclusion. Data collected included demographics, type of surgery, PROMs compliance, and discharge care. Descriptive statistics and multivariate analysis (MVA) were performed to compare pre- and postoperative compliance rates. RESULTS: Of the 474 included patients, 177 were administered paper PROMs, while 297 were electronic. Preoperatively, 101 patients (57.1%) had any portion of their paper PROMs available; 179 (60.3%) had any of their electronic PROMs available (p = 0.492). Among all patients, 76 (42.9%) and 170 (57.2%) had all of their completed preop PROMs available (p = 0.003). Among patients with any of their preop PROMs completed, 75.2% with paper and 95.0% with electronic were completed in their entirety (p < 0.001). Similar trends were observed among postoperative PROMs. MVA demonstrated electronic delivery as the only significant correlate with pre- and post-operative PROMs compliance (p < 0.001 and p = 0.003, respectively). CONCLUSIONS: No differences were observed across modalities when considering any available PROMs, yet electronic PROM delivery was associated with higher completion of PROMs. In order to improve the quality of patient-reported data, electronic delivery with alternative methods of quality improvement may be considered to increase PROMs retention rates.

Subsidence Rates Associated With Porous 3D-Printed Versus Solid Titanium Cages in Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVE: To determine whether 3D-printed porous titanium (3DPT) interbody cages offer any clinical or radiographic advantage over standard solid titanium (ST) interbody cages in transforaminal lumbar interbody fusions (TLIF). METHODS: A consecutive series of adult patients undergoing one- or two-level TLIF with either 3DPT or ST "banana" cages were analyzed for patient reported outcome measures (PROMs), radiographic complications, and clinical complications. Exclusion criteria included clinical or radiographic follow-up less than 1 year. RESULTS: The final cohort included 90 ST interbody levels from 74 patients, and 73 3DPT interbody levels from 50 patients for a total of 124 patients. Baseline demographic variables and comorbidity rates were similar between groups (P > .05). Subsidence of any grade occurred more frequently in the ST group compared with the 3DPT group (24.4% vs 5.5%, respectively, P = .001). Further, the ST group was more likely to have higher grades of subsidence than the 3DPT group (P = .009). All PROMs improved similarly after surgery and revision rates did not differ between groups (both P > .05). On multivariate analysis, significant positive correlators with increasing subsidence grade included greater age (P = .015), greater body mass index (P = .043), osteoporosis/osteopenia (P < .027), and ST cage type (P = .019). CONCLUSIONS: When considering interbody material for TLIF, both ST and 3DPT cages performed well; however, 3DPT cages were associated with lower rates of subsidence. The clinical relevance of these findings deserves further randomized, prospective investigation.

Promotion of higher rates of early fusion using activated titanium versus polyetheretherketone cages in adults undergoing 1- and 2-level transforaminal lumbar interbody fusion procedures: a randomized controlled trial.

OBJECTIVE: There is ongoing debate on the relative benefits and drawbacks of polyetheretherketone (PEEK) versus titanium (Ti) in generating a bone-to-implant surface microenvironment conducive to osseointegration. Micro- and nanoscale internal and topographic cage modifications have recently been posited to facilitate osseointegration and fusion, but human in vivo confirmation remains lacking. The authors of this study sought to directly compare early radiological outcomes in adults undergoing 1- and 2-level transforaminal lumbar interbody fusion (TLIF) procedures using either PEEK or nano-etched Ti interbody cages with an incorporated microlattice structure. METHODS: Patients were enrolled in a single academic center using a single-blind randomized controlled superiority design. Screening was undertaken from a pool of consecutive patients eligible for TLIF to undergo placement in a 1:1 ratio of either lordotic PEEK or activated Ti cages at each level of 1- or 2-level procedures. An a priori power analysis was performed and a preplanned interim analysis was undertaken once 50 of 70 patients were enrolled. Patient study data were collected perioperatively and uploaded to a Research Electronic Data Capture (REDCap) registry. Interbody fusion was assessed based on 6-month postoperative lumbar dual-energy CT (DECT) studies using the method of Brantigan and Steffee, as modified to describe the Fraser definition of locked pseudarthrosis (Brantigan-Steffee-Fraser [BSF] scale). RESULTS: In the final cohort of 50 patients, 40 interbody levels implanted with PEEK cages were compared with 34 interbody levels with activated Ti cages. The trial was stopped early given the results of an interim analysis with respect to the primary outcome. Surgical parameters including number of levels treated, average cage height, and position were not different between groups. For the PEEK and activated Ti groups, 20.6% versus 84.0% demonstrated BSF grade 3 fusion on 6-month postoperative DECT imaging (p < 0.001). Subsidence at 6 months on DECT was identified in 12 (41.4%) of PEEK levels versus 5 (20.8%) of activated Ti levels (p < 0.001). BSF-3 grading was predictive of segmental stability and numeric rating scale (NRS) leg pain improvement at 1 year postoperatively. Oswestry Disability Index and NRS back and leg pain scores all improved similarly in both cohorts at 1 year postoperatively. CONCLUSIONS: Activated Ti interbody cages mediate early fusion at significantly higher rates with lower rates of subsidence as compared with PEEK cages. These findings support the idea that interbody cage microscale properties, including surface topography, may play a primary role in facilitating osseointegration and fusion.

Demineralized Bone Matrix and Fibers in Spinal Fusion.

Formation of bony fusion after arthrodesis depends on osteoinduction, osteoconduction, and osteogenesis. Traditionally, the patient's own bone, or autograft, has been used to provide biological material necessary for these steps. However, the amount of autograft obtainable is often inadequate. Modern spine surgery has adopted the use of many autograft extenders or replacements, such as demineralized bone matrix or fibers. The present article covers the history of bone grafting, the production and technical details of demineralized bone matrix, and the evidence supporting its use in spine fusions.