The Effect of Osteoporosis on Complications and Reoperation Rates After Surgical Management of Adult Thoracolumbar Spinal Deformity: A Systematic Review and Meta Analysis.

STUDY DESIGN: Systematic Review. OBJECTIVES: While substantial research has explored the impact of osteoporosis on patients undergoing adult spinal deformity (ASD) correction, the literature remains inconclusive. As such, the purpose of this study is to synthesize and analyze existing studies pertaining to osteoporosis as a predictor of postoperative outcomes in ASD surgery. METHODS: We performed a systematic review and meta-analysis to determine the effect that a diagnosis of osteoporosis, based on ICD-10 coding, dual-energy X-ray absorptiometry (DEXA) or computed tomography, has on the incidence of adverse outcomes following surgical correction of ASD. Statistical analysis was performed using Comprehensive Meta-Analysis (Version 2) using a random effects model to account for heterogeneity between studies. RESULTS: After application of inclusion and exclusion criteria, 36 and 28 articles were included in the systematic review and meta-analysis, respectively. The meta-analysis identified greater rates of screw loosening amongst osteoporotic patients (70.5% vs 31.9%, P = .009), and decreased bone mineral density in patients who developed proximal junctional kyphosis (PJK) (.69 vs .79 g/cm2, P = .001). The systematic review demonstrated significantly increased risk of any complication, reoperation, and proximal junctional failure (PJF) associated with reduced bone density. No statistical difference was observed between groups regarding fusion rates, readmission rates, and patient-reported and/or functional outcome scores. CONCLUSION: This study demonstrates a higher incidence of screw loosening, PJK, and revision surgery amongst osteoporotic ASD patients. Future investigations should explore outcomes at various follow-up intervals in order to better characterize how risk changes with time and to tailor preoperative planning based on patient-specific characteristics.

Cervical Disc Arthroplasty: Rationale, Designs, and Results of Randomized Controlled Trials.

BACKGROUND: This review outlines clinical data and characteristics of current Food and Drug Administration (FDA)-approved implants in cervical disc replacement/cervical disc arthroplasty (CDR/CDA) to provide a centralized resource for spine surgeons. METHODS: Randomized controlled trials (RCTs) on CDR/CDA were identified using a search of the PubMed, Web of Science, and Google Scholar databases. The initial search identified 69 studies. Duplicates were removed, and the following inclusion criteria were applied when determining eligibility of RCTs for the current review: (1) discussing CDR/CDA prosthesis and (2) published within between 2010 and 2020. Studies without clinical data or that were not RCTs were excluded. All articles were reviewed independently by 2 authors, with the involvement of an arbitrator to facilitate consensus on any discrepancies. RESULTS: A total of 34 studies were included in the final review. Findings were synthesized into a comprehensive table describing key features and clinical results for each FDA-approved CDR/CDA implant and are overall suggestive of expanding indications and increasing utilization. CONCLUSIONS: RCTs have provided substantial evidence to support CDR/CDA for treating single- and 2-level cervical degenerative disc disease in place of conventional anterior cervical discectomy and fusion. CLINICAL RELEVANCE: This review provides a resource that consolidates relevant clinical data for current FDA-approved implants to help spine surgeons make an informed decision during preoperative planning.

Systematic Review and Meta-Analysis of the Effect of Osteoporosis on Fusion Rates and Complications Following Surgery for Degenerative Cervical Spine Pathology.

BACKGROUND: As the elderly population grows, the increasing prevalence of osteoporosis presents a unique challenge for surgeons. Decreased bone strength and quality are associated with hardware failure and impaired bone healing, which may increase the rate of revision surgery and the development of complications. The purpose of this review is to determine the impact of osteoporosis on postoperative outcomes for patients with cervical degenerative disease or deformity. METHODS: A systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and Medical Subject Headings terms involving spine surgery for cervical degenerative disease and osteoporosis were performed. This review focused on radiographic outcomes, as well as surgical and medical complications. RESULTS: There were 16 studies included in the degenerative group and 9 in the deformity group. Across degenerative studies, lower bone mineral density was associated with increased rates of cage subsidence in osteoporotic patients undergoing operative treatment for cervical degenerative disease. Most studies reported varied results on the relationship between osteoporosis and other outcomes such as revision and readmission rates, costs, and perioperative complications. Our meta-analysis suggests that osteoporotic patients carry a greater risk of reduced fusion rates at 6 months and 1 year postoperatively. With respect to cervical deformity correction, although individual complication rates were unchanged with osteoporosis, the collective risk of incurring any complication may be increased in patients with poor bone stock. CONCLUSIONS: Overall, the literature suggests that outcomes for osteoporotic patients after cervical spine surgery are multifactorial. Osteoporosis seems to be a significant risk factor for developing cage subsidence and pseudarthrosis postoperatively, whereas reports on medical and hospital-related metrics were inconclusive. Our findings highlight the challenges of caring for osteoporotic patients and underline the need for adequately powered studies to understand how osteoporosis changes the risk index of patients undergoing cervical spine surgery. CLINICAL RELEVANCE: In patients undergoing cervical spine surgery for degenerative disease, osteoporosis is a significant risk factor for long-term postoperative complications-notably cage subsidence and pseudarthrosis. Given the elective nature of these procedures, interdisciplinary collaboration between providers should be routinely implemented to enable medical optimization of patients prior to cervical spine surgery.

The Incidence of Vertebral Artery Injury in Cervical Spine Surgery.

BACKGROUND: Previously reported estimates of vertebral artery injuries (VAIs) during cervical spine surgery relied on self-reported survey studies and retrospective cohorts, which may not be reflective of national averages. The largest study to date reports an incidence of 0.07%; however, significant variation exists between different cervical spine procedures. This study aimed to identify the incidence of VAIs in patients undergoing cervical spine procedures for degenerative pathologies. METHODS: In this retrospective cohort study, a national insurance database was used to access data from the period 2010-2020 of patients who underwent anterior cervical discectomy and fusion, anterior corpectomy, posterior cervical fusion (C3-C7), or C1-C2 posterior fusion for degenerative pathologies. Patients who experienced a VAI were identified, and frequencies for the different procedures were compared. RESULTS: This study included 224,326 patients, and overall incidence of VAIs across all procedures was 0.03%. The highest incidence of VAIs was estimated in C1-C2 posterior fusion (0.12%-1.10%). The number of patients with VAIs after anterior corpectomy, anterior cervical discectomy and fusion, and posterior fusion was 14 (0.06%), 43 (0.02%), and 26 (0.01%), respectively. CONCLUSIONS: This is the largest study to date to our knowledge that provides frequencies of VAIs in patients undergoing cervical spine surgery in the United States. The overall incidence of 0.03% is lower than previously reported estimates, but significant variability exists between procedures, which is an important consideration when counseling patients about risks of surgery.

Nationwide Analysis of Sacroiliac Joint Fusion Trends: Regional Variations in Utilization and Population Characteristics.

STUDY DESIGN/SETTING: Retrospective cohort analysis. OBJECTIVES: This study evaluates utilization and demographic trends for sacroiliac joint (SIJ) fusions across the United States (US). METHODS: Patients who underwent SIJ fusion from 2010-2021 were identified within the PearlDiver national database using International Classification of Disease (ICD-9, ICD-10) and Current Procedural Terminology (CPT) codes. Indications for trauma, malignancy, or infection were excluded. Demographic, clinical, and procedure characteristics were recorded along with annual utilization rates. Annual percent change (APC) was calculated to identify increasing or decreasing utilization from prior years. Negative binomial regression was performed to project subsequent utilization for 2022-2028. Chi-squared analysis followed by post-hoc comparisons were used to compare differences in diagnostic indications and clinical features associated with SIJ fusion across regions. Bonferroni adjustments were applied to P-values for pairwise analyses. RESULTS: Overall, 18 032 patients (69.8% female, mean age = 51.0 + 13.4 years) underwent SIJ fusion between 2010 and 2021. Annual utilization increased by 33.5% on average. The South comprised the largest proportion of cases (48.9%). Projections for 2022-2028 predict continued growth in procedures, with an overall increase of 1100% from 1350 cases in 2021 to 16 195 by end of 2028. Spondyloarthropathy-induced sacroilitis was the most prevalent diagnostic indication nationwide (51%). Of patients undergoing SIJ fusion, 18% had a prior lumbar fusion, and only 45% received a preoperative diagnostic SIJ injection. CONCLUSION: As SIJ fusion is increasingly utilized to treat refractory SIJ-based pain, establishing evidence-based guidelines, improving diagnostic strategies, and defining indications are imperative to support growing applications within clinical practice.

Complication Rates and Utilization Trends of 3-Level Posterior Column Osteotomy Compared to Single-Level Pedicle Subtraction Osteotomy.

OBJECTIVE: The objective of this study is to assess differences in complication profiles between 3-level posterior column osteotomy (PCO) and single-level pedicle subtraction osteotomy (PSO) as both are reported to provide similar degrees of sagittal correction. METHODS: The PearlDiver database was queried retrospectively using International Classification of Disease, 9th and 10th edition and Current Procedural Terminology codes to identify patients who underwent PCO or PSO for degenerative spine disease. Patients under age 18 or with history of spinal malignancy, infection, or trauma were excluded. Patients were separated into 2 cohorts, 3-level PCO or single-level PSO, matched at a 1:1 ratio based on age, sex, Elixhauser comorbidity index, and number of fused posterior segments. Thirtyday systemic and procedure-related complications were compared. RESULTS: Matching resulted in 631 patients for each cohort. PCO patients had decreased odds of respiratory (odds ratio [OR], 0.58; 95% confidence interval [CI], 0.43-0.82; p = 0.001) and renal complications (OR, 0.59; 95% CI, 0.40-0.88; p = 0.009) compared to PSO patients. There was no significant difference in cardiac complications, sepsis, pressure ulcer, dural tear, delirium, neurologic injuries, postoperative hematoma, postoperative anemia, or overall complications. CONCLUSION: Patients who undergo 3-level PCO have decreased respiratory and renal complications compared to single-level PSO. No differences were found in the other complications studied. Considering both procedures achieve similar sagittal correction, surgeons should be aware that 3-level PCO offers an improved safety profile compared to single-level PSO.

The Effect of COVID-19 on Spine Surgery.

STUDY DESIGN/SETTING: Retrospective cohort analysis. OBJECTIVES: To characterize the impact of COVID-19 on utilization of the ten most common spine procedures and percentages of outpatient procedures. METHODS: The PearlDiver national database was queried from January 2010 to April 2021 for short (<6 segments) and long segment posterior instrumented fusion (≥6 segments), posterior cervical fusion, anterior cervical decompression and fusion (ACDF), cervical laminectomy, laminoplasty, and disc arthroplasty, lumbar laminectomy, microdiscectomy, and interbody fusion. Annual procedure utilization between January 2010 through April 2021 was recorded and compared. Monthly trends were compared to January 2020. Outpatient trends were compared between 2010-2019 and 2019-2021 using segmented linear regression. RESULTS: Overall, all ten procedures decreased 4.3% in 2020 compared to 2019 and increased 6.3% in 2021 compared to 2019. March and April of 2020 had the largest decreases, with March 2020 decreasing 18.2% and April 2020 decreasing 51.6% compared to January 2020. Despite increasing COVID cases in January 2021, overall procedure utilization decreased only 1.8% compared to January 2020, and increased later in 2021 with April 2021 case volumes increasing by 138% compared to January 2020. Outpatient utilization of short segment posterior lumbar fusion and lumbar interbody fusion significantly increased during this time (P < .001). CONCLUSION: The greatest impact on spine surgery volume from the COVID-19 pandemic occurred in March and April 2020. Spine procedure utilization was otherwise similar or increased compared to January 2020. Additionally, the volume of outpatient short segment posterior fusion and lumbar interbody fusions increased during this time period.

Anteroposterior pelvic radiograph findings correlate with sagittal spinopelvic motion.

It has been well documented in the arthroplasty literature that lumbar degenerative disc disease (DDD) contributes to abnormal spinopelvic motion. However, the relationship between the severity or pattern of hip osteoarthritis (OA) as measured on an anteroposterior (AP) pelvic view and spinopelvic biomechanics has not been well investigated. Therefore, the aim of the study is to examine the association between the severity and pattern of hip OA and spinopelvic motion. A retrospective chart review was conducted to identify patients undergoing primary total hip arthroplasty (THA). Plain AP pelvic radiographs were reviewed to document the morphological characteristic of osteoarthritic hips. Lateral spine-pelvis-hip sitting and standing plain radiographs were used to measure sacral slope (SS) and pelvic femoral angle (PFA) in each position. Lumbar disc spaces were measured to determine the presence of DDD. The difference between sitting and standing SS and PFA were calculated to quantify spinopelvic motion (ΔSS) and hip motion (ΔPFA), respectively. Univariate analysis and Pearson correlation were used to identify morphological hip characteristics associated with changes in spinopelvic motion. In total, 139 patients were included. Increased spinopelvic motion was observed in patients with loss of femoral head contour, cam deformity, and acetabular bone loss (all p < 0.05). Loss of hip motion was observed in patients with loss of femoral head contour, cam deformity, and acetabular bone loss (all p < 0.001). A decreased joint space was associated with a decreased ΔPFA (p = 0.040). The presence of disc space narrowing, disc space narrowing > two levels, and disc narrowing involving the L5-S1 segment were associated with decreased spinopelvic motion (all p < 0.05). Preoperative hip OA as assessed on an AP pelvic radiograph predicts spinopelvic motion. These data suggest that specific hip osteoarthritic morphological characteristics listed above alter spinopelvic motion to a greater extent than others.

The Role of Psychosocial Screening in Patient Selection for Spine Surgery: A Review.

BACKGROUND: The purpose of this review is to provide a brief history of previous attempts at developing patient screening tools and to further examine the definitions of these psychological concepts, relevance to clinical outcomes, and implications for spine surgeons during preoperative patient assessments. METHODS: A literature review was performed by 2 independent researchers to identify original manuscripts related to spine surgery and novel psychological concepts. The history of presurgical psychology screening was also studied, and definitions of frequently utilized metrics were detailed. RESULTS: Seven manuscripts were identified that utilized psychological metrics for preoperative risk assessments and correlated outcomes with these scores. The metrics most frequently used in the literature included resilience, patient activation, grit, and self-efficacy. DISCUSSION: Current literature favors resilience and patient activation as important metrics for preoperative patient screening. Available studies demonstrate significant associations between these character traits and patient outcomes. Further research is warranted to investigate the roles of preoperative psychological screening to optimize patient selection in spine surgery. CLINICAL RELEVANCE: The purpose of this review is to provide clinicians with a reference for available psychosocial screening tools and their relevance to patient selection. This review also serves to guide future research directions given the importance of this topic.

The Correlation Between Pelvic Motion and Lumbar Motion in Patients Presenting With a Lumbar Spinal Pathology: Implications for Assessing Dislocation Risk in Total Hip Arthroplasty.

Background: Arthroplasty surgeons use the change in sacral slope (ΔSS) from sitting to standing as a measure of spinal motion. The relationship between ΔSS and the change in lumbar lordosis (ΔLL), an established spinal motion measure, has not been well studied. This study aims to determine the correlation between ΔSS and ΔLL. Methods: Consecutive patients presenting to a spine clinic from 2020 to 2021 at a single institution were retrospectively studied. Standing and sitting lateral radiographs were measured for SS and LL. Patients were divided using ΔSS and ΔLL into stiff (0°-9°), normal (10°-30°), or hypermobile (>30°) category. Patients with a ΔSS-determined normal or hypermobile spine but a ΔLL-determined stiff spine were compared to the rest of the cohort. Results: Overall, 100 patients were included. Of these patients, 47% had the same classification when looking at ΔSS and ΔLL, whereas 53% had conflicting classifications. Twenty percent of patients had a ΔSS-determined normal or hypermobile spine but ΔLL-determined stiff spine. The correlation between ΔSS and ΔLL was 0.510 (P < .001). When isolating patients who underwent lumbar fusion, the correlation between ΔSS and ΔLL was 0.345 (P < .001). Conclusions: ΔSS has a moderate correlation with ΔLL in patients presenting for evaluation of their lumbar spine but low correlation in patients with lumbar fusion. In our cohort, 20% of patients had a ΔSS-determined normal or hypermobile spine but a ΔLL-determined stiff spine, representing a potential high-risk dislocation cohort not captured by ΔSS alone. Arthroplasty surgeons should revisit classifying spinal motion based solely on ΔSS.

Preoperative Epidural Steroid Injection Does Not Increase Infection Risk Following Posterior Cervical Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purpose of this study was to characterize the infection risk of preoperative epidural steroid injection (ESI) in patients undergoing posterior cervical surgery. SUMMARY OF BACKGROUND DATA: ESI is a helpful tool for alleviating pain and is often used as a diagnostic tool before cervical surgery. However, a recent small-scale study found that ESI before cervical fusion was associated with an increased risk of postoperative infection. MATERIALS AND METHODS: Patients from 2010 to 2020 with cervical myelopathy, spondylosis, and radiculopathy who underwent posterior cervical procedure including laminectomy, laminoforaminotomy, fusion, or laminoplasty were queried from the PearlDiver database. Patients who underwent revision or fusion above C2 or who had a diagnosis of neoplasm, trauma, or preexisting infection were excluded. Patients were divided on whether they received an ESI within 30 days before the procedure and subsequently matched by age, sex, and preoperative comorbidities. The χ 2 analysis was used to calculate the risk of postoperative infection within 90 days. Logistic regression controlling for age, sex, Elixhauser Comorbidity Index, and operated levels was conducted within the unmatched population to assess infection risk for injected patients across procedure subgroups. RESULTS: Overall, 299,417 patients were identified with 3897 having received a preoperative ESI and 295,520 who did not. Matching resulted in 975 in the injected group and 1929 in the control group. There was no significant difference in postoperative infection rate in those who received an ESI within 30 days preoperatively and those who did not (3.28% vs. 3.78%, odds ratio=0.86, 95% CI: 0.57-1.32, P =0.494). Logistic regression accounting for age, sex, Elixhauser Comorbidity Index, and levels operated demonstrated that injection did not significantly increase infection risk in any of the procedure subgroups. CONCLUSIONS: The present study found no association between preoperative ESI within 30 days before surgery and postoperative infection in patients undergoing posterior cervical surgery.

Preoperative radiographic findings associated with postoperative spinopelvic risk factors for instability following total hip arthroplasty.

Postoperative spinopelvic changes are associated with increased dislocation risk following total hip arthroplasty (THA). The aim of this study was to identify preoperative patient and radiographic factors associated with high-risk postoperative spinopelvic parameters. A retrospective review of consecutive THA patients who received preoperative and postoperative sitting and standing lateral lumbar spine-hip radiographs with minimum radiographic and clinical follow-up of 10 months was performed. Patient demographics were recorded and preoperative standing and sitting sacral slope (SS), anteinclination, pelvic femoral angle (PFA), and combined sagittal index (CSI) were measured. High-risk patients were defined by decreased spinopelvic motion (∆SS from sitting to standing of >10°), increased hip motion (∆PFA from sitting to standing of >10°), or decreased CSI of >10° at final follow-up compared with preoperative measurements. Univariate and multivariate regression analyses were used to identify preoperative demographic and radiographic factors associated with these high-risk categories. One hundred and fifty-three patients were included with an average age of 62 years, average body mass index of 27.8 kg/m2 , and average follow-up of 16.2 months. At 1-year follow-up, 43 (28.1%) patients demonstrated a decreased ∆SS > 10° and 67 (43.7%) patients demonstrated an increased ∆PFA > 10° compared with preoperative values. Sitting CSI decreased by >10° in 17 (11.1%) patients. Preoperative increased sitting PFA (adjusted odds ratio [aOR] 1.057, p < 0.001) and decreased preoperative hip motion (∆PFA) were associated with decreased sitting CSI of >10° at 10-month follow-up. Increased spinopelvic motion (∆SS) and decreased hip motion (∆PFA) preoperatively are associated with postoperative radiographic changes that be associated with increased dislocation risk.

Are Cervical Disc Arthroplasty Medicare Reimbursement Trends Sustainable?

BACKGROUND: Cervical disc arthroplasty (CDA) was originally approved by the US Food and Drug Administration (FDA) in 2007 as a motion-sparing procedure to treat cervical degenerative disc disease. Since then, promising results from randomized control trials have led to increasing popularity. However, data discussing monetary trends are limited. The aim of this study was to determine how utilization, hospital charges, and Medicare physician reimbursement for CDA have changed over time. METHODS: In this retrospective cohort study, International Classification of Diseases procedure codes were used to identify all patients who underwent CDA from 2007 to 2017 in the National Inpatient Sample database. The Physician Fee Schedule Look-up Tool from the Centers for Medicare and Medicaid Services was queried for primary CDA using current procedural terminology codes to determine Medicare physician reimbursement from 2009 to 2021. Nominal monetary values were adjusted for inflation using the Consumer Price Index and inflation-adjusted data reported in 2021 US dollars. RESULTS: A total of 33,079 weighted patients who underwent CDA were included for analysis. CDA utilization increased by 183% from 2007 to 2017, with Medicare beneficiary utilization increasing 149%. Inflation-adjusted total hospital charges for CDA increased by 22.4%. However, inflation-adjusted Medicare physician reimbursement fell by 1.20% per year, demonstrating a total decrease of 12.9%, starting at $1928 in 2009 and declining to $1679 in 2021. CONCLUSIONS: While utilization and total hospital charges for CDA continue to rise, Medicare physician reimbursement has not shown the same trend. In fact, inflation-adjusted reimbursement has seen a steady decline since FDA approval in 2007. If this trend persists, it may become unsustainable for physicians to continue offering CDA to Medicare patients. As disproportionate increases in hospital charges incentivize a transition to outpatient CDA, stricter patient selection criteria associated with outpatient procedures may create health care disparities for Medicare patients and those with higher comorbidity burden. CLINICAL RELEVANCE: This study shows the decreasing reimbursement trends for CDA, which may disproportionately affect Medicare patients and those with increased comorbidities.

Safety and Efficacy of Rivaroxaban in Primary Total Hip and Knee Arthroplasty.

BACKGROUND: An optimal venous thromboembolism prophylaxis agent should balance efficacy and safety. While rivaroxaban provides effective venous thromboembolism prophylaxis after total joint arthroplasty, it may be associated with higher rates of bleeding. This study aimed to compare the safety and efficacy of rivaroxaban to aspirin and enoxaparin. METHODS: A large national database was queried for patients who underwent elective primary total hip (THA) or total knee arthroplasty (TKA) from January 2015 through December 2020 who received rivaroxaban, aspirin, or enoxaparin. Multivariate analyses were performed to assess the 90-day risk of bleeding and thromboembolic complications. Among TKA patients identified, 86,721 (10.8%) received rivaroxaban, 408,038 (50.8%) received aspirin, and 108,377 (13.5%) received enoxaparin. Among THA patients, 42,469 (9.5%) received rivaroxaban, 242,876 (54.5%) received aspirin, and 59,727 (13.4%) received enoxaparin. RESULTS: After accounting for confounding factors, rivaroxaban was associated with increased risk of transfusion (TKA: adjusted odds ratio [aOR] = 2.58, P < .001; THA: aOR 1.64, P < .001), pulmonary embolism (TKA: aOR = 1.25, P = .007), and deep vein thrombosis (TKA: aOR = 1.13, P = .022) compared to aspirin. Compared to enoxaparin, rivaroxaban was associated with an increased risk of combined bleeding events (TKA: aOR = 1.07, P < .001, THA: aOR = 1.11, P < .001), but decreased risk of combined prothrombotic events (THA: aOR = 0.85, P = .036). CONCLUSION: Rivaroxaban chemoprophylaxis following TKA and THA was associated with an increased risk of bleeding and prothrombotic complications compared to aspirin and enoxaparin.

The Role of Sex Hormones in Degenerative Disc Disease.

STUDY DESIGN: Narrative review. OBJECTIVES: The purpose of this review is to outline the role of sex hormones, particularly estrogen, in the pathogenesis of degenerative disc disease (DDD). METHODS: A narrative review of studies discussing sex hormones and intervertebral disc (IVD) degeneration was conducted through a search of bibliographic databases to identify various mechanisms involved in effectuating DDD. RESULTS: Estrogen-deficient states negatively impact various aspects of IVD function. These internal hormone environments reflect routine changes that commonly arise with physiologic aging and can compromise IVD structural integrity through a host of processes. Additionally, allosteric molecules such as micro-RNAs (mi-RNAs) and G protein-coupled estrogen receptors (GPER) antagonists can bind to estrogen receptors and inhibit protective downstream effects with estrogen receptor signaling. Furthermore, cursory studies have observed chondrogenic effects with testosterone supplementation, although the specific mechanism remains unclear. CONCLUSIONS: Regulation of sex hormones, namely estrogen and testosterone, significantly impacts the structural integrity and function of IVDs. Uncovering underlying interactions driving these regulatory processes can facilitate development of novel, clinical therapies to treat DDD.

Does Prednisone Dose Affect Rates of Periprosthetic Joint Infection Following Primary Total Hip and Total Knee Arthroplasty?

BACKGROUND: Prednisone use is associated with higher rates of periprosthetic joint infection (PJI) following total joint arthroplasty (TJA). However, the relationship between prednisone dosage and infection risk is ill-defined. Therefore, this study aimed to assess the relationship between prednisone dosage and rates of PJI following TJA. METHODS: A national database was queried for all elective total hip (THA) and total knee arthroplasty (TKA) patients between 2015 and 2020. Patients who received oral prednisone following TJA were matched in a 1:2 ratio based on age and sex to patients who did not. Univariate and multivariate regression analyses were performed to assess the 90-day risk of infectious complications based on prednisone dosage as follows: 0 to 5, 6 to 10, 11 to 20, 21 to 30, and >30 milligrams. Overall, 1,322,043 patients underwent elective TJA (35.9% THA, 64.1% TKA). Of these, 14,585 (1.1%) received prednisone and were matched to 29,170 patients who did not. RESULTS: After controlling for confounders, TKA patients taking prednisone were at increased risk for sepsis (adjusted odds ratio [aOR] 2.76, P < .001), PJI (aOR 2.67, P < .001), and surgical site infection (aOR: 2.56, P = .035). THA patients taking prednisone were at increased risk for sepsis (aOR: 3.21, P < .001) and PJI (aOR: 1.73, P = .001). No dose-dependent relationship between prednisone and infectious complications was identified when TJA was assessed in aggregate. CONCLUSION: Patients receiving prednisone following TJA were at increased risk of PJI and sepsis. A dose-dependent relationship between prednisone and infectious complications was not identified. Arthroplasty surgeons should be aware of these risks and counsel TJA patients who receive prednisone therapy.

A Decreasing National Trend in Lumbar Disc Arthroplasty.

STUDY DESIGN: Retrospective National Database Study. OBJECTIVES: The aim of this study was to investigate the national trend of lumbar disc arthroplasty (LDA) utilization from 2005 to 2017. METHODS: Patients undergoing primary LDA between 2005 and 2017 were identified in the National Inpatient Sample (NIS) database. Year of the procedure, demographic, socioeconomic, hospital, and cost parameters were analyzed. The data was weighted using provided weights from the NIS database to generate national estimates of LDA procedure incidence. Lastly, we assessed the incidence of cervical disc arthroplasty (CDA) between 2005 and 2017 to serve as a historical comparison. RESULTS: An estimated 20 460 patients underwent primary LDA in the United States between 2005 and 2017. There was an initial decrease in LDA procedures between 2005 and 2006 and then a plateau between 2006 and 2009. From 2010 to 2013, there was a significant year-over-year decrease in annual LDA procedures performed, followed by a second plateau from 2014 to 2017. Overall, LDA procedures decreased 82% from 2005 to 2017. Over the same time, the annual incidence of CDA utilization increased 795% from approximately 474 procedures in 2005 to 4245 procedures in 2017 (P < .01). CONCLUSIONS: Lumbar disc arthroplasty utilization decreased 82% from 2005 to 2017, with a significant decrease in the rate of utilization noted after 2010. The utilization of LDA to treat selected degenerative lumbar conditions has not paralleled the increasing popularity of CDA, and, in fact, has demonstrated a nearly opposite utilization trend.

Is Intraoperative Dexamethasone Utilization Associated With Increased Rates of Periprosthetic Joint Infection Following Total Joint Arthroplasty?

BACKGROUND: Intraoperative dexamethasone can reduce postoperative pain and nausea following total knee (TKA) and total hip arthroplasty (THA). To the best of our knowledge, no study to date has been adequately powered to detect the risk of periprosthetic joint infection (PJI) from early dexamethasone exposure. This study aimed to assess PJI rates and complications in patients undergoing primary elective TKA and THA who received intraoperative dexamethasone. METHODS: A national database was used to identify adults undergoing primary elective TKA and THA between 2015 and 2020. Patients who received intraoperative dexamethasone and those who did not were identified. The primary endpoint was 90-day risk of infectious complications. Secondary end points included thromboembolic, pulmonary, renal, and wound complications. Multivariate analyses were performed to assess the risk of all endpoints between cohorts. Between 2015 and 2020, 1,322,025 patients underwent primary elective TJA, of which 857,496 (64.1%) underwent TKA and 474,707 (35.9%) underwent TKA. RESULTS: In patients who underwent TKA, dexamethasone was associated with lower risk of PJI (adjusted odds ratio: 0.87, 95% CI: 0.82-0.93, P < .001) as well as other secondary endpoints such as pulmonary embolism, deep vein thrombosis, and acute kidney injury. In patients who underwent THA, dexamethasone was associated with a lower risk of PJI (adjusted odds ratio: 0.80, 95% CI: 0.73-0.86, P < .001) as well as other secondary endpoints such as pulmonary embolism, deep vein thrombosis, acute kidney injury, and pneumonia. CONCLUSION: Intraoperative dexamethasone was not associated with increased risk of infectious complications. The data presented here provide evidence in support of intraoperative dexamethasone utilization during primary TKA or THA.

The Incidence of Double Crush Syndrome in Surgically Treated Patients.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVES: Cervical radiculopathy and peripheral entrapment neuropathies often have overlapping symptoms that are difficult to distinguish on physical examination. Small-scale studies have attempted to report the incidence of this phenomenon, often called double crush syndrome (DCS), with varying results. The present study aims to determine the incidence of concomitant cervical radiculopathy and peripheral nerve compression and to determine if the DCS hypothesis, which states that compression of a nerve at one site leaves it more susceptible to compression at another, is valid. METHODS: The PearlDiver database was queried from 2010 to 2020. The incidence of peripheral neuropathy in cervical radiculopathy was assessed. Propensity score matching was used to determine if patients with cervical radiculopathy were more likely to have peripheral nerve compression compared to controls, and vice versa, to test the DCS hypothesis. RESULTS: The database contains records of 90,772 632 patients. The incidence of carpal tunnel syndrome (CTS) or peripheral ulnar nerve compression (PUnC) in cervical radiculopathy was 9.98% and 3.15%, respectively. The incidence of both carpal tunnel syndrome and PUnC in cervical radiculopathy was 1.84%. Patients with cervical radiculopathy were more likely than matched controls to have both CTS (P < .001) and PUnC (P < .001). Patients with CTS (P < .001) and with PUnC (P < .001) were more likely to have cervical radiculopathy than the control cohort. CONCLUSIONS: The incidence of DCS is reported. Patients with cervical radiculopathy are more likely than matched controls to have peripheral nerve compression, and vice versa, in support of the DCS hypothesis.

Secondary Fracture Rate After Vertebral Osteoporotic Compression Fracture Is Decreased by Anti-Osteoporotic Medication but Not Increased by Cement Augmentation.

BACKGROUND: Painful vertebral osteoporotic compression fractures (OCFs) are often treated with cement augmentation, although controversies exist as to whether or not this increases the secondary fracture risk. Prevention of secondary fracture includes treatment of underlying osteoporosis. The purposes of this study were to determine (1) whether cement augmentation increases the rate of secondary fracture compared with nonoperative management, (2) whether anti-osteoporotic medications reduce the rate of secondary fracture, and (3) the rate of osteoporosis treatment with medications following vertebral OCF. METHODS: The PearlDiver database was queried for all patients with a diagnosis of OCF from 2015 to 2019. Patients were excluded if they were <50 years old, had a diagnosis of spinal neoplasm or infection, or underwent lumbar fusion in the perioperative period. Secondary fracture risk was assessed using univariate and multivariate logistic regression analysis, with kyphoplasty, vertebroplasty, anti-osteoporotic medications, age, gender, and Elixhauser Comorbidity Index as variables. RESULTS: A total of 36,145 patients were diagnosed with an OCF during the study period. Of those, 25,904 (71.7%) underwent nonoperative management and 10,241 (28.3%) underwent cement augmentation, including 1,556 who underwent vertebroplasty and 8,833 who underwent kyphoplasty. Patients who underwent nonoperative management had a secondary fracture rate of 21.8% following the initial OCF, compared with 14.5% in the vertebroplasty cohort and 18.5% in the kyphoplasty cohort, which was not a significant difference on multivariate analysis. In the entire cohort, 2,833 (7.8%) received anti-osteoporotic medications and 33,312 (92.2%) did not. The rate of secondary fracture was 10.1% in patients who received medications and 21.9% in those who did not, which was a significant difference on multivariate analysis (odds ratio = 1.23, p < 0.001). CONCLUSIONS: Cement augmentation did not alter the rate of secondary fracture, whereas anti-osteoporotic medications significantly decreased the risk of subsequent OCF by 19%. Only 7.8% of patients received a prescription for an anti-osteoporotic medication following the initial OCF. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.