Circulating microRNAs May Be Predictive of Degenerative Cervical Myelopathy.

STUDY DESIGN: Basic Science. OBJECTIVE: The objective of this study was to identify a unique serum profile of circulating miRNAs and inflammatory markers in patients with degenerative cervical myelopathy (DCM) compared to healthy controls (HC). SUMMARY OF BACKGROUND DATA: Currently, DCM is diagnosed with a combination of history, physical examination, and close correlation to advanced imaging. To date, no serum marker has been identified to be diagnostic of this condition. METHODS: Whole venous blood was collected from patients with DCM as well as healthy age- and sex-matched controls. miRNA was extracted from venous blood and a screening analysis was initially conducted to identify miRNA dysregulation in DCM patients. RT-qPCR was used to analyze the expression of 2 specific miRNAs based on screening analysis and literature review. Bioinformatics analysis was used to identify gene networks and potential targets of the miRNA. In addition, the serum inflammatory profile of DCM and HC groups was differentiated using a pro-inflammatory panel. RESULTS: Thirty-six patients were enrolled in the DCM group (36.1% male, 61.5±9.5 y) while 35 patients were enrolled in the HC group (31.4% male, 57.5±8.9 y). Of the 15 total miRNAs differentially expressed between DCM and HC groups, two were selected for further analysis: miR-223-3p (upregulated) and miR-451a (downregulated). Functional gene network analysis revealed the highest-ranking gene network was involved in neurological disease, while the most overexpressed miRNA in this network (miR-233-3p) was noted to have over 100 targets including CDKN1B and the insulin receptor. Serum cytokine analysis showed significant upregulation of several pro-inflammatory cytokines in the DCM cohort compared to the HC group. CONCLUSION: DCM patients demonstrated a set of unique circulating miRNAs in addition to a different serum inflammatory profile compared to HC. These miRNAs may potentially serve as targets for future therapeutic intervention or diagnostic/prognostic testing.

The Effect of C2 Muscular Exposure Technique on Radiographic and Clinical Outcomes After C2-T2 Posterior Cervical Fusion.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To determine whether the C2 exposure technique was a predictor of change in cervical alignment and patient-reported outcomes measures (PROMs) after posterior cervical decompression and fusion (PCDF) for degenerative indications. BACKGROUND: In PCDF handling of the C2 posterior paraspinal musculature during the operative approach varies by surgeon technique. To date, no studies have investigated whether maintenance of the upper cervical semispinalis cervicis attachments as compared with complete reflection of upper cervical paraspinal musculature from the posterior bony elements is associated with superior radiographic and clinical outcomes after PCDF. PATIENTS AND METHODS: All adult patients who underwent C2-T2 PCDF for myelopathy or myeloradiculopathy at multi-institutional academic centers between 2013 and 2020 were retrospectively identified. Patients were dichotomized by the C2 exposure technique into semispinalis preservation or midline muscular reflection groups. Preoperative and short and long-term postoperative radiographic outcomes (upper cervical alignment, global alignment, and fusion status) and PROMs (Visual Analog Scale-Neck, Neck Disability Index, and Short Form-12) were collected. Univariate analysis compared patient factors, radiographic measures, and PROMs across C2 exposure groups. RESULTS: A total of 129 patients met the inclusion/exclusion criteria (73 muscle preservation and 56 muscle reflection). Patients in the muscular preservation group were on average younger (P= 0.005) and more likely to have bone morphogenic protein (P< 0.001) and C2 pars screws (P= 0.006) used during surgery. Preoperative to postoperative changes in C2 slope, C2 tilt, C2-C3 segmental lordosis, C2-C3 listhesis, C0-C2 Cobb angle, proximal junctional kyphosis, ADI, C1 lamina-occiput distance, C2 sagittal vertical axis, C2-C7 lordosis, and PROMs at all follow-up intervals did not vary significantly by C2 exposure technique. Likewise, there were no significant differences in fusion status, C2-C3 pseudoarthrosis, C2 screw loosening, and complication and revision rates between C2 exposure groups. CONCLUSIONS: Preservation of C2 semispinalis attachments versus muscular reflection did not significantly impact cervical alignment, clinical outcomes, or proximal junction complications in long-segment PCDF. LEVEL OF EVIDENCE: Level III.

The effect of C2 screw type on perioperative outcomes and long-term stability after C2-T2 posterior cervical decompression and fusion.

PURPOSE: To determine if C2 pedicle versus pars screw type predicts change in fusion status, C2 screw loosening, cervical alignment, and patient-reported outcomes measures (PROMs) after C2-T2 posterior cervical decompression and fusion (PDCF). METHODS: All adult patients who underwent C2-T2 PCDF for myelopathy or myeloradiculopathy between 2013-2020 were retrospectively identified. Patients were dichotomized by C2 screw type into bilateral C2 pedicle and bilateral C2 pars screw groups. Preoperative and short- and long-term postoperative radiographic outcomes and PROMs were collected. Univariate and multivariate analysis compared patient factors, fusion status, radiographic measures, and PROMs across groups. RESULTS: A total of 159 patients met the inclusion/exclusion criteria (76 bilateral pedicle screws, 83 bilateral pars screws). Patients in the C2 pars relative to C2 pedicle screw group were on average more likely to have bone morphogenic protein (p = 0.001) and four-millimeter diameter rods utilized intraoperatively (p = 0.033). There were no significant differences in total construct and C2-3 fusion rate, C2 screw loosening, or complication and revision rates between C2 screw groups in univariate and regression analysis. Changes in C2 tilt, C2-3 segmental lordosis, C0-2 Cobb angle, proximal junctional kyphosis, atlanto-dens interval, C1 lamina-occiput distance, C2 sagittal vertical axis, C2-7 lordosis, and PROMs at all follow-up intervals did not vary significantly by C2 screw type. CONCLUSION: There were no significant differences in fusion status, hardware complications, and radiographic and clinical outcomes based on C2 screw type following C2-T2 PCDF. Accordingly, intraoperative usage criteria can be flexible based on patient vertebral artery positioning and surgeon comfort level.

A Standardized Curriculum Improves Trainee Rod Bending Proficiency in Spinal Deformity Surgery. Results of a Prospective Randomized Controlled Educational Study.

INTRODUCTION: Surgical simulation is increasingly being accepted as a training platform to promote skill development and a safe surgical technique. Preliminary investigations in spine surgery show that simulation paired with educational intervention can markedly improve trainee performance. This study used a newly developed thoracolumbar fusion rod bending model to assess the effect of a novel educational curriculum and simulator training on surgical trainee rod bending speed and proficiency. METHODS: Junior (PGY1 to 2) and senior (PGY3-fellow) surgical trainees at a single academic institution were prospectively enrolled in a rod bending simulation using a T7-pelvis spinal fusion model. Participants completed two simulations, with 1 month between first and second attempts. Fifty percent of surgeons in each training level were randomized to receive an educational curriculum (rod bending technique videos and unlimited simulator practice) between simulation attempts. Rod bending simulation proficiency was determined by the percentage of participants who completed the task (conclusion at 20 minutes), time to task completion or conclusion, and number of incomplete set screws at task conclusion. Participants completed a preparticipation and postparticipation survey. Univariate analysis compared rod bending proficiency and survey results between education and control cohorts. RESULTS: Forty trainees (20 junior and 20 senior) were enrolled, with 20 participants randomized to the education and control cohorts. No notable differences were observed in the first simulation rod bending proficiency or preparticipation survey results between the education and control cohorts. In the second simulation, the education versus the control cohort demonstrated a significantly higher completion rate ( P = 0.01), shorter task time ( P = 0.009), fewer incomplete screws ( P = 0.003), and greater experience level ( P = 0.008) and comfort level ( P = 0.002) on postparticipation survey. DISCUSSION: Trainees who participated in a novel educational curriculum and simulator training relative to the control cohort improved markedly in rod bending proficiency and comfort level. Rod bending simulation could be incorporated in existing residency and fellowship surgical skills curricula. LEVEL OF EVIDENCE: I.

Inhibition of Neurogenic Inflammatory Pathways Associated with the Reduction in Discogenic Back Pain.

STUDY DESIGN: Retrospective cohort study. PURPOSE: This study aimed to determine whether the initiation of anti-calcitonin gene-related peptide (CGRP inhibitor) medication therapy for migraines was also associated with improvements in back/neck pain, mobility, and function in a patient population with comorbid degenerative spinal disease and migraine. OVERVIEW OF LITERATURE: CGRP upregulates pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-6, brain-derived neurotrophic factor, and nerve growth factor in spinal spondylotic disease, which results in disc degeneration and sensitization of nociceptive neurons. Although CGRP inhibitors can quell neurogenic inflammation in migraines, their off-site efficacy as a therapeutic target for discogenic back/neck pain conditions remains unknown. METHODS: All adult patients diagnosed with spinal spondylosis and migraine treated with CGRP inhibitors at a single academic institution between 2017 and 2020 were retrospectively identified. Patient demographic and medical data, follow-up duration, migraine severity and frequency, spinal pain, functional status, and mobility before and after the administration of CGRP inhibitors were collected. Paired univariate analysis was conducted to determine significant changes in spinal pain, headache severity, and headache frequency before and after the administration of CGRP inhibitors. The correlation between changes in the spinal pain score and functional or mobility improvement was assessed with Spearman's rho. RESULTS: In total, 56 patients were included. The mean follow-up time after the administration of CGRP inhibitors was 123 days for spinal pain visits and 129 days for migraine visits. Back/neck pain decreased significantly (p <0.001) from 6.30 to 4.36 after starting CGRP inhibitor therapy for migraine control. As recorded in the spine follow-up notes, 25% of patients experienced a functional improvement in the activities of daily living, and 17.5% experienced mobility improvement while taking CGRP inhibitors. Change in back/ neck pain moderately correlated (ρ=-0.430) with functional improvement but was not correlated with mobility improvement (ρ=-0.052). CONCLUSIONS: Patients taking CGRP inhibitors for chronic migraines with comorbid degenerative spinal conditions experienced significant off-target reduction of back/neck pain.

Outcomes after salvage reverse shoulder arthroplasty for failed primary fixation or hemiarthroplasty for proximal humerus fractures: A systematic review.

Background: Salvage reverse shoulder arthroplasty (RSA) for failed proximal humerus fractures (PHFs) fixation and hemiarthroplasty (HA) may maximize outcomes in the absence of tuberosity healing or a chronically torn rotator cuff. The purpose of this systematic review was to examine the improvement in clinical outcomes for patients after revision RSA was performed for failed PHFs fixation or HA. Methods: An electronic database search of SCOPUS, PubMed, Embase, MEDLINE, SPORTDiscus, CINAHL, and ClinicalTrials.gov was performed. A meta-analysis was carried out to determine weighted mean outcome differences between two primary intervention cohorts (failed fixation: open reduction and internal fixation, intramedullary nail, or K-wire vs. failed HA). Results: Fifteen studies were included (primary fixation: 208 patients; HA: 162 patients). Patients improved meaningfully in all clinical outcomes after revision surgery (constant: 18.5-48.3; abduction: 44-95; forward flexion: 47-107; external rotation: 5-10), with a 16.2% complication and 9.4% revision rate. The failed fixation group performed significantly better than the failed HA group in postoperative constant (fixation: 53.3 vs. HA: 45.1, p = 0.016) and shoulder abduction (fixation: 102 vs. HA: 87, p = 0.026). Conclusions: RSA is a successful revision intervention for primary PHF operative failures with the greatest benefit for failures of primary fixation versus HA.

Effect of Clinical and Radiographic Degenerative Spondylolisthesis Classification on Patient-reported Outcomes and Spinopelvic Parameters for Patients With Single-level L4-L5 Degenerative Spondylolisthesis After Lumbar Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To determine whether preoperative clinical and radiographic degenerative spondylolisthesis (CARDS) classification is associated with differences in patient-reported outcomes and spinopelvic parameters after posterior decompression and fusion for L4-L5 degenerative spondylolisthesis (DS). SUMMARY: The CARDS classification for lumbar DS, an alternative to the Meyerding system, considers additional radiographic findings such as disc space collapse and segmental kyphosis and stratifies DS into 4 radiographically distinct classes. Although CARDS has been shown to be a reliable and reproducible method for classifying DS, very few studies have assessed whether the CARDS types represent distinct clinical entities. PATIENTS AND METHODS: A retrospective cohort analysis was conducted on patients with L4-L5 DS who underwent posterior lumbar decompression and fusion. Changes in spinopelvic alignment and patient-reported outcomes measures, including recovery ratios and percentage of patients achieving the minimal clinically important difference, were compared among patients in each CARDS classification 1-year postoperatively using analysis of variance or Kruskal-Wallis H with Dunn post hoc analysis. Multiple linear regression determined whether CARDS groups significantly predicted patient-reported outcomes measures, lumbar lordosis (LL), and pelvic incidence-lumbar lordosis mismatch (PI-LL) while controlling for demographic and surgical characteristics. RESULTS: Preoperative type B spondylolisthesis predicted decreased improvement in "physical component and mental component score of the short form-12" compared with type A spondylolisthesis (ß-coefficient = -5.96, P = 0.031) at 1 year. Significant differences were found between CARDS groups with regards to ΔLL (A: -1.63 degrees vs B: -1.17 degrees vs C: 2.88 degrees vs D: 3.19 degrees, P = 0.010) and ΔPI-LL (A: 1.02 degrees vs B: 2.09 degrees vs C: -2.59 degrees vs D: -3.70 degrees, P = 0.012). Preoperative type C spondylolisthesis was found to predict increased LL (ß-coefficient = 4.46, P = 0.0054) and decreased PI-LL (ß-coefficient = -3.49, P = 0.025) at 1 year compared with type A spondylolisthesis. CONCLUSIONS: Clinical and radiographic outcomes differed significantly by preoperative CARDS classification type for patients undergoing posterior decompression and fusion for L4-L5 DS. LEVEL OF EVIDENCE: Level III.

Varenicline mitigates the increased risk of pseudarthrosis associated with nicotine.

BACKGROUND CONTEXT: High serum nicotine levels increase the risk of nonunion after spinal fusion. Varenicline, a pharmaceutical adjunct for smoking cessation, is a partial agonist designed to displace and outcompete nicotine at its receptor binding site, thereby limiting downstream activation. Given its mechanism, varenicline may have therapeutic benefits in mitigating nonunion for active smokers undergoing spinal fusion. PURPOSE: To compare fusion rate and fusion mass characteristics between cohorts receiving nicotine, varenicline, or concurrent nicotine and varenicline after lumbar fusion. STUDY DESIGN: Rodent noninstrumented spinal fusion model. METHODS: Sixty eight-week-old male Sprague-Dawley rats weighing approximately 300 grams underwent L4-5 posterolateral fusion (PLF) surgery. Four experimental groups (control: C, nicotine: N, varenicline: V, and combined: NV [nicotine and varenicline]) were included for analysis. Treatment groups received nicotine, varenicline, or a combination of nicotine and varenicline delivered through subcutaneous osmotic pumps beginning two weeks before surgery until the time of sacrifice at age 14 weeks. Manual palpation testing, microCT imaging, bone histomorphometry, and biomechanical testing were performed on harvested spinal fusion segments. RESULTS: Control (p=0.016) and combined (p=0.032) groups, when compared directly to the nicotine group, demonstrated significantly greater manual palpation scores. The fusion rate in the control (93.3%) and combined (93.3%) groups were significantly greater than that of the nicotine group (33.3%) (p=0.007, both). Biomechanical testing demonstrated greater Young's modulus of the fusion segment in the control (17.1 MPa) and combined groups (34.5 MPa) compared to the nicotine group (8.07 MPa) (p<0.001, both). MicroCT analysis demonstrated greater bone volume fraction (C:0.35 vs N:0.26 vs NV:0.33) (p<0.001, all) and bone mineral density (C:335 vs N:262 vs NV:328 mg Ha/cm3) (p<0.001, all) in the control and combined groups compared to the nicotine group. Histomorphometry demonstrated a greater mineral apposition rate in the combined group compared to the nicotine group (0.34 vs 0.24 µm/day, p=0.025). CONCLUSION: In a rodent spinal fusion model, varenicline mitigates the adverse effects of high nicotine serum levels on the rate and quality of spinal fusion. CLINICAL SIGNIFICANCE: These findings have the potential to significantly impact clinical practice guidelines and the use of pharmacotherapy for active nicotine users undergoing fusion surgery.

Delayed open treatment of aortic penetration by a thoracic pedicle screw: illustrative case.

BACKGROUND: Iatrogenic aortic injury from pedicle screw malpositioning or anterior prominence in posterior spinal fusion represents a rare but potentially devasting complication. While intraoperative aortic injury is associated with hemodynamic instability, delayed presentations of pedicle screw aortic impingement or violation often present insidiously with pseudoaneurysm or vascular remodeling in clinically asymptomatic patients. Currently, there is a lack of guidance in the field for the recommended surveillance, urgency of operative intervention, and optimal surgical management of delayed pedicle screw aortic injuries. OBSERVATIONS: The following case study discusses the open treatment of delayed thoracic aortic penetration from an excessively long T12 pedicle screw in an asymptomatic adolescent patient with idiopathic scoliosis. The pedicle screw prominence anteriorly was corrected by burring the screw tip until it was flush with the vertebral body. The associated aortic injury was addressed with open vascular repair via primary anastomosis supplemented with a bovine pericardial patch. LESSONS: Complete aortic wall penetration from an excessively long thoracic pedicle screw with otherwise stable screw positioning may be addressed most effectively with a single anterior surgical approach for open aortic repair and screw tip burring.

Does a High Postoperative Opioid Dose Predict Chronic Use After ACDF?

OBJECTIVE: The purpose of this study is to determine if increased postoperative prescription opioid dosing is an isolated predictor of chronic opioid use after anterior cervical diskectomy and fusion (ACDF). METHODS: A retrospective cohort analysis of patients undergoing ACDF for degenerative diseases from 2016-2019 at a single institution was performed. Preoperative and postoperative opioid and benzodiazepine prescriptions, including morphine milligram equivalents (MMEs) and duration of use, were obtained from the Pennsylvania Prescription Drug Monitoring Program. Univariate analysis compared patient demographics and surgical factors across groups on the basis of postoperative opioid dose (high: MME ≥90, low: MME <90) and chronicity of use (chronic: ≥120 days or >10 prescriptions). Logistic regressions identified predictors of high opioid dose and chronic use. RESULTS: A total of 385 patients were included. Preoperative opioid tolerance and tobacco use were associated with high postoperative opioid dose and chronic usage. Younger age correlated with high-dose prescriptions. Increased body mass index and preoperative benzodiazepine use were associated with chronic opioid use. Chronic postoperative opioid use correlated with high-dose prescriptions, change in opioid prescribed, private pay scripts, and more than 1 prescriber and pharmacy. Logistic regression identified high postoperative opioid dose, opioid tolerance, increased body mass index, and no prior cervical surgery as predictors of chronic opioid use. Regression analysis determined younger age, increased medical comorbidities, and opioid tolerance to be predictors for high MME prescriptions. CONCLUSIONS: High postoperative opioid dose independently predicted chronic opioid use after ACDF regardless of preoperative opioid tolerance.

Do Patient Outcomes Predict Loss to Long-Term Follow-Up After Spine Surgery?

OBJECTIVE: To determine if spine surgery patients with greater improvement in patient-reported outcomes measures (PROMs) at early postoperative follow-up are more likely to be lost to follow-up at the 1-year and 2-year postoperative visits. METHODS: All patients older than 18 years who underwent primary or revision decompression or fusion surgery for degenerative spinal conditions at an academic institution were retrospectively identified. Univariate analysis compared patient demographics, surgical factors, and changes in short-term and long-term postoperative PROMs (Neck Disability Index, Oswestry Disability Index, visual analog scale [VAS] neck, VAS arm, VAS back, VAS leg, and Short-Form 12 Physical and Mental Component Scores) across groups with and without 1 year and 2 years follow-up. Logistic regression isolated predictors of loss to follow-up. RESULTS: A total of 1412 patients were included. Younger patient age, primary surgery, and single surgical approach independently predicted loss at 1 year follow-up. Female sex predicted loss at 2 years follow-up, whereas multilevel fusion surgery predicted attendance at 2 years clinical follow-up. In patients lost at 1 year follow-up compared with those who attended, preoperative to 3-month Mental Component Score and VAS neck pain improvement was significantly greater. When comparing patients based on 2 years follow-up status, VAS back pain improvement at 1 year postoperatively was significantly greater in patients lost to 2 years follow-up. All other changes in PROMs did not differ significantly by 1 or 2 years follow-up attendance. CONCLUSIONS: Overall patient outcomes were not found to affect loss to long-term follow-up after spine surgery. The general lack of association between postoperative follow-up status and clinical outcome may limit bias introduced in retrospective PROM studies.

The Impact of Preoperative Symptom Duration on Patient Outcomes After Posterior Cervical Decompression and Fusion.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVES: To determine if decreased preoperative symptom duration is associated with greater clinical improvement in function and myelopathic symptoms after posterior cervical decompression and fusion (PCDF). METHODS: All patients over age 18 who underwent primary PCDF for cervical myelopathy or myeloradiculopathy at a single institution between 2014 and 2020 were retrospectively identified. Patient demographics, surgical characteristics, duration of symptoms, and preoperative and postoperative patient reported outcomes measures (PROMs) including modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), Visual Analogue Scale (VAS) Neck, VAS Arm, and SF-12 were collected. Univariate and multivariate analyses were performed to compare change in PROMs and minimum clinically important difference achievement (%MCID) between symptom duration groups (< 6 months, 6 months-2 years, > 2 years). RESULTS: Preoperative symptom duration groups differed significantly by sex and smoking status. Patients with < 6 months of preoperative symptoms improved significantly in all PROMs. Patients with 6 months-2 years of preoperative symptoms did not improve significantly in mJOA, Physical Component Scores (PCS), or NDI. Patients with > 2 years of symptoms failed to demonstrate significant improvement in mJOA, NDI, or Mental Component Scores (MCS). Univariate analysis demonstrated significantly decreased improvement in mJOA with longer symptom durations. Increased preoperative symptom duration trended toward decreased %MCID for mJOA and MCS. Regression analysis demonstrated that preoperative symptom duration of > 2 years relative to < 6 months predicted decreased improvement in mJOA and NDI and decreased MCID achievement for mJOA and MCS. CONCLUSION: Increased duration of preoperative symptoms (> 2 years) before undergoing PCDF was associated with decreased postoperative improvement in myelopathic symptoms.

Does Facet Distraction Affect Patient Outcomes After ACDF?

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study is to determine if there is a correlation between the amount of facet distraction and postoperative patient-reported outcomes after ACDF. METHODS: A retrospective cohort analysis of patients undergoing 1 to 3 level ACDF for degenerative pathologies at a single academic center was performed. Each patient received upright, lateral cervical spine x-rays at the immediate postoperative time point from which interfacet distance (facet distraction) was measured. Patient-reported outcome measures including NDI, PCS-12, MCS-12, VAS Neck, and VAS Arm pain scores were obtained preoperatively and at short-term (<3 months) and long-term (>1 year) follow-up. Receiver operating curves were generated to evaluate the possibility of a critical interfacet distraction distance. Univariate and multivariate analysis were performed to compare outcomes between groups based on the degree of facet distraction. RESULTS: A total of 229 patients met the inclusion criteria. Receiver operating curves failed to yield a critical interfacet distraction distance associated with worse post-operative outcomes. Patients were instead grouped based on facet distraction distance below and above the third quartile (0.8mm-2.0 mm, 2.0mm-3.7 mm), with 173 and 56 patients in each respective group. Univariate analysis did not detect any statistically significant differences in outcome measures, recovery ratio, or % MCID achievement at short- and long-term follow-up between groups. Multivariate analysis also failed to demonstrate any significant differences between the facet distraction groups. CONCLUSION: Increased interfacet distance did not correlate with increased neck pain or disability after an ACDF.

Impact of surface roughness and bulk porosity on spinal interbody implants.

Spinal fusion surgeries are performed to treat a multitude of cervical and lumbar diseases that lead to pain and disability. Spinal interbody fusion involves inserting a cage between the spinal vertebrae, and is often utilized for indirect neurologic decompression, correction of spinal alignment, anterior column stability, and increased fusion rate. The long-term success of interbody fusion relies on complete osseointegration between the implant surface and vertebral end plates. Titanium (Ti)-based alloys and polyetheretherketone (PEEK) interbody cages represent the most commonly utilized materials and provide sufficient mechanics and biocompatibility to assist in fusion. However, modification to the surface and bulk characteristics of these materials has been shown to maximize osseointegration and long-term stability. Specifically, the introduction of intrinsic porosity and surface roughness has been shown to affect spinal interbody mechanics, vascularization, osteoblast attachment, and ingrowth potential. This narrative review synthesizes the mechanical, in vitro, in vivo, and clinical effects on fusion efficacy associated with introduction of porosity in Ti (neat and alloy) and PEEK intervertebral implants.

Single-level Lumbar Fusion Versus Total Joint Arthroplasty: A Comparison of 1-year Outcomes.

INTRODUCTION: Primary hip and knee arthroplasty represent two of the most successful orthopaedic surgical interventions in the past century. Similarly, lumbar fusion (LF) remains a valuable, evidence-based option to relieve pain and disability related to spinal degenerative conditions. This study evaluates the relative improvements in 1-year health-related quality of life (HRQOL) measures among patients undergoing primary single-level LF, primary total hip arthroplasty (THA), and primary total knee arthroplasty (TKA). METHODS: Patients older than 18 years who underwent primary single-level posterior LF (posterolateral decompression and fusion with or without transforaminal lumbar interbody fusion, involving any single lumbar level), TKA, and THA at a single academic institution were retrospectively identified. Patient demographics and surgical characteristics were collected. HRQOL measures were collected preoperatively and at 1-year postoperative time point including Short-Form 12 Physical Component Score (PCS) and Mental Component Score (MCS) along with subspecialty-specific outcomes. RESULTS: A total of 2,563 patients were included (346 LF, 1,035 TKA, and 1,182 THA). Change in MCS-12 and PCS-12 after LF did not vary markedly by preoperative diagnosis. LF patients had a significantly lower preoperative MCS-12 (LF: 50.8, TKA: 53.9, THA: 52.9, P < 0.001), postoperative MCS-12 (LF: 52.5, TKA: 54.8, THA: 54.5, P < 0.001), postoperative PCS-12 (LF: 40.1, TKA: 44.0, THA: 43.9, P < 0.001), ΔPCS-12 (LF: 7.9, TKA: 10.8, THA: 11.9, P < 0.001), and PCS-12 recovery ratio (LF: 10.7%, TKA: 15.1%, THA 16.6%, P < 0.001) compared with TKA and THA patients. In regression analysis, both TKA and LF were found to be independently associated with a smaller ΔPCS-12 improvement (TKA: ß = -1.36, P = 0.009; LF: ß = -4.74, P < 0.001) compared with THA. TKA (ß = -1.42, P = 0.003) was also independently associated with a smaller ΔMCS-12 improvement compared with THA. CONCLUSIONS: Patients undergoing single-level LF, TKA, and THA demonstrate notable improvements in HRQOL outcomes at 1 year postoperatively compared with preoperative baseline scores. The greatest improvements were found among THA patients, followed subsequently by TKA and LF patients. Both LF and TKA were independently associated with markedly less improvement in physical disability at 1 year postoperatively compared with THA. STUDY DESIGN: Retrospective Cohort Study.

The Usefulness of Closed Incision Negative Pressure Wound Therapy After Spinal Fusion: A Systematic Review and Meta-Analysis.

OBJECTIVE: To determine if closed incision negative pressure wound therapy (ciNPWT) decreases surgical site infection (SSI) or wound dehiscence after spinal fusion. METHODS: Following PRISMA guidelines, a systematic review and meta-analysis were conducted to identify studies using ciNPWT after spinal fusion. Funnel plots and quality scores of the articles were performed to determine if the articles were at risk of bias. Forest plots were conducted to identify the treatment effect of ciNPWT after spinal fusion. RESULTS: A total of 8 studies comprising 1061 patients who received ciNPWT or a standard postoperative dressing after spinal fusion were included. The rate of SSI (ciNPWT, 4.49% [95% confidence interval (CI), 2.48-8.00] vs. control, 11.32% [95% CI, 7.51-16.70]; P = 0.0103) was significantly lower for patients treated with ciNPWT. A fixed-effects model showed no significant difference between patients who received ciNWPT or a standard postoperative dressing with respect to requiring reoperations for wound debridement (odds ratio, 1.25; 95% CI, 0.64-2.41). In addition, wound dehiscence was not significantly different between the 2 groups, although it was nonsignificantly lower in ciNWPT-treated patients (ciNPWT, 4.59% [95% CI, 2.49-8.31] vs. control: 7.48% [95% CI, 4.38-12.47]; P = 0.23). CONCLUSIONS: ciNPWT may reduce the rates of SSI after spinal fusion. The use of ciNWPT may also significantly reduce the burden associated with postoperative wound complications, but the meta-analysis was insufficiently powered to make this association. Additional studies may identify a subset of patients who benefit from ciNPWT for other wound-related complications.

Is Patient Geography a Risk Factor for Chronic Opioid Use After ACDF?

The social and medical implications intrinsic to patient zip codes with high opioid fatality may reveal residence in these locations to be a risk factor predicting chronic opioid use after anterior cervical discectomy and fusion (ACDF). The purpose of this study is to determine if residence in Pennsylvania zip codes with high incidence of opioid overdose deaths is a risk factor for chronic postoperative opioid use after ACDF. Preoperative opioid usage did not vary meaningfully between high- and low-risk zip code groups. Patients in high-risk opioid overdose zip codes were significantly more likely to exhibit chronic postoperative opioid use. The Kaplan-Meier curve demonstrated that opioid discontinuation was less probable at any postoperative time for patients residing in high opioid fatality zip codes. Logistic regression found opioid tolerance, smoking, and depression to predict extended opioid use.

Patients with Dual Shoulder-Spine Disease: Does Operative Order Affect Clinical Outcomes?

OBJECTIVE: 1) To analyze the effect of operative sequence (anterior cervical discectomy and fusion [ACDF] first or rotator cuff repair [RCR] first) on surgical outcomes after both procedures for patients with dual shoulder-spine injuries and 2) to determine how operative sequence affects patient-reported outcome measures (PROMs) after surgery. METHODS: Patients >18 years of age who underwent primary ACDF and primary RCR at our institution were retrospectively identified. Only patients with overlapping symptoms before the first procedure were included. Patients were divided into 2 cohorts (ACDF first or RCR first). Patient demographics, surgical characteristics, surgical outcomes, and PROMs were compared between groups. Multivariate linear regression models were developed to determine if operative order was predictive of improvements in PROM scores at the 1-year postoperative point after the second procedure. Alpha was set at P < 0.05. RESULTS: Of the 85 patients included, 44 patients (51.8%) underwent ACDF first, whereas 41 patients (48.2%) underwent RCR first. There were no significant differences in the rate of 90-day readmission, spine reoperations, and rotator cuff reoperations between groups (all, P > 0.05). Multivariate linear regression showed that undergoing an ACDF first was not a significant predictor of Δ Mental Component Score of the Short-Form 12 (ß = -2.78; P = 0.626) and Δ Physical Component Score of the Short-Form 12 (ß = 7.74; P = 0.077) at the 1-year postoperative point after the second procedure. CONCLUSIONS: For patients with dual shoulder-spine injuries who are appropriate surgical candidates, undergoing ACDF first compared with RCR first does not result in significant differences in clinical surgical or patient-reported outcomes.

The Effect of Anterior Cervical Discectomy and Fusion Procedure Duration on Patient-Reported Outcome Measures.

OBJECTIVE: To determine whether operative duration of anterior cervical discectomy and fusion (ACDF) significantly affects patient-reported outcome measures (PROMs) 90 days after surgery and at 1-year follow-up. METHODS: Patients who underwent primary 1-level to 4-level ACDF were retrospectively identified. Demographic data and PROMs were collected through chart review. Patients were split into short, medium, and long tertiles based on procedure duration. PROM surveys were administered preoperatively as baseline measurements, at initial follow-up (between 60 and 120 days postoperatively), and at 1 year postoperatively. Outcomes included Neck Disability Index, Short-Form 12 Physical Component Score (PCS-12), Short-Form 12 Mental Component Score, visual analog scale (VAS) neck score, and VAS arm score. RESULTS: Significant short-term improvements were found across all groups for all PROMs. All groups showed long-term improvements in Short-Form 12 Mental Component Score, PCS-12, Neck Disability Index, VAS neck score, and VAS arm score, with the exception of the medium-duration group in PCS-12 (P = 0.093). On multivariate analysis, short-duration procedures predicted better improvement in VAS neck score (ß = -1.01; P = 0.012) and VAS arm score (ß = -1.38; P = 0.002) compared with long-duration procedures, whereas medium-duration procedures resulted in better improvement in VAS arm score (ß = -1.00; P = 0.011). Further, short and medium duration was a predictor of decreased length of hospital stay (ß = -0.67, P = 0.001 and ß = -0.59, P = 0.001, respectively) compared with long-duration procedures. CONCLUSIONS: All groups improved after ACDF regardless of surgical duration. Further, surgical duration was not a predictor of differing improvement in physical function or disability.

Effect of Fellow Involvement and Experience on Patient Outcomes in Spine Surgery.

INTRODUCTION: Investigations in spine surgery have demonstrated that trainee involvement correlates with increased surgical time, readmissions, and revision surgeries; however, the specific effects of spine fellow involvement remain unelucidated. This study aims to investigate the isolated effect of fellow involvement on surgical timing and patient-reported outcomes measures (PROMs) after spine surgery and evaluate how surgical outcomes differ by fellow experience. METHODS: All patients aged 18 years or older who underwent primary or revision decompression or fusion for degenerative diseases and/or spinal deformity between 2017 and 2019 at a single academic institution were retrospectively identified. Patient demographics, surgical factors, intraoperative timing, transfusion status, length of stay (LOS), readmissions, revision rate, and preoperative and postoperative PROMs were recorded. Surgeries were divided based on spine fellow participation status and occurrence in the start or end of fellowship training. Univariate and multivariate analyses compared outcomes across fellow involvement and fellow experience groups. RESULTS: A total of 1,108 patients were included. Age, preoperative diagnoses, number of fusion levels, and surgical approach differed markedly by fellow involvement. Fellow training experience groups differed by patient smoking status, preoperative diagnosis, and surgical approach. On univariate analysis, spine fellow involvement was associated with extended total theater time, induction start to cut time, cut to close time, and LOS. Increased spine fellow training was associated with reduced cut to close time and LOS. On regression, fellow involvement predicted cut to close extension while increased fellow training experience predicted reduction in cut to close time, both independent of surgical factors and assisting residents or physician assistants. Transfusions, readmissions, revision rate, and PROMs did not differ markedly by fellow involvement or experience. CONCLUSION: Spine fellow participation predicted extended procedural duration. However, the presence of a spine fellow did not affect long-term postoperative outcomes. Furthermore, increased fellow training experience predicted decreased procedural time, underscoring a learning effect. AVAILABILITY OF DATA AND MATERIAL: The data sets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. LEVEL OF EVIDENCE: Level 3.