Health Care Costs Following Anterior Cervical Discectomy and Fusion or Cervical Disc Arthroplasty.

STUDY DESIGN: Observational cohort study. OBJECTIVE: To describe the postoperative costs associated with both anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) in the two-year period following surgery. SUMMARY OF BACKGROUND DATA: CDA has become an increasingly common alternative to ACDF for the treatment of cervical disc disorders. Although a number of studies have compared clinical outcomes between both procedures, much less is known about the postoperative economic burden of each procedure. MATERIALS AND METHODS: By analyzing a commercial insurance claims database (Marketscan, Merative), patients who underwent one-level or two-level ACDF and CDA procedures between January 1, 2017 and December 31, 2017 were identified and included in the study. The primary outcome was the cost of payments for postoperative management in the two-year period following ACDF or CDA. Identified postoperative interventions included in the study were: (i) physical therapy, (ii) pain medication, (iii) injections, (iv) psychological treatment, and (iv) subsequent spine surgeries. RESULTS: Totally, 2304 patients (age: 49.0±9.4 yr; male, 50.1%) were included in the study. In all, 1723 (74.8%) patients underwent ACDF, while 581 (25.2%) underwent CDA. The cost of surgery was similar between both groups (ACDF: $26,819±23,449; CDA: $25,954±20,620; P =0.429). Thirty-day, 90-day, and two-year global costs were all lower for patients who underwent CDA compared with ACDF ($31,024 vs. $34,411, $33,064 vs. $37,517, and $55,723 vs. $68,113, respectively). CONCLUSION: Lower two-year health care costs were found for patients undergoing CDA compared with ACDF. Further work is necessary to determine the drivers of these findings and the associated longer-term outcomes.

Variable flip angle T1 mapping and multi-echo T2 and T2* mapping magnetic resonance imaging sequences allow quantitative assessment of canine lumbar disc degeneration.

Magnetic resonance imaging is the gold standard for diagnosing intervertebral disc (IVD) degeneration in dogs. However, published methods for quantifying severity or progression of IVD degeneration are currently limited. Mapping MRI sequences are used in humans for quantifying IVD degeneration but have rarely been applied in dogs. The objective of this prospective, method comparison study was to evaluate variable flip angle T1 mapping and multiecho T2 and T2* mapping as methods for quantifying canine lumbar IVD degeneration in twenty canine patients without clinical signs of spinal disease. Ventral and dorsal lumbar IVD widths were measured on radiographs, and lumbar IVDs were assigned a qualitative Pfirrmann grade based on standard T2-weighted sequences. T1, T2, and T2* relaxation times of the nucleus pulposus (NP) were measured on corresponding maps using manual-drawn ROIs. Strong intra- and interrater agreements were found (P < 0.01) for NP relaxation times. Radiographic IVD widths and T1, T2, and T2* mapping NP relaxation times were negatively correlated with Pfirrmann grading (P < 0.01). Significant differences in T1 NP relaxation times were found between Pfirrmann grade I and the other grades (P < 0.01). Significant differences in T2 and T2* NP relaxation times were found between grade I and the other grades and between grades II and III (P < 0.01). Findings indicated that T1, T2, and T2* MRI mapping sequences are feasible in dogs. Measured NP relaxation times were repeatable and decreased when Pfirrmann grades increased. These methods may be useful for quantifying the effects of regenerative treatment interventions in future longitudinal studies.

Assessment of a Discogenic Pain Animal Model Induced by Applying Continuous Shear Force to Intervertebral Discs.

BACKGROUND: Chronic discogenic pain includes degeneration-driven changes under the mechanical macroenvironment of an internal disc, which leads to the progressive changes of biochemical microenvironment that induce abnormal ingrowth of the nociceptor. The propriety of the animal model reflecting the pathologic natural history has not been assessed. OBJECTIVES: This study investigated the biochemical evidence of chronic discogenic pain by employing a discogenic pain animal model induced by shear force. STUDY DESIGN: Animal study utilizing rats in vivo model of a shear force device. METHODS: Fifteen rats were divided into 3 groups (n = 5/group) according to the period for which sustained dorsoventral shear force was applied (1 week or 2 weeks); the control group received the spinous attachment unit, without a spring. Pain data were collected using von Frey hairs on the hind paws. Growth factor and cytokine abundance was analyzed in the dorsal root ganglion (DRG) and plasma. RESULTS: After the shear force devices were installed, the significant variables were found to markedly increase in the DRG tissues of the 2-week group; however, they were not altered in the 1-week group. Specifically, interleukin (IL)-6, neurogrowth factor (NGF), transforming growth factor (TGF)-alpha, platelet-derived growth factor (PDGF)-beta, and vascular endothelial growth factor (VEGF) were increased. Meanwhile, the plasma levels of tumor necrosis factor-alpha, IL-1beta, IL-5, IL-6, IL-12, and NGF were increased in the 1-week group; whereas, TGF-alpha, PDGF-beta, and VEGF were increased in the 2-week group. LIMITATIONS: The limitations include the general limitations of quadrupedal animals, the poor precision and flexural deformation of shear force devices, inaccuracies regarding the evaluation of histological denaturation, and short intervention and observational periods. CONCLUSIONS: This animal model effectively generated biochemical responses to shear loading with evidence of neurological changes induced without direct macrodamage to the outer annulus fibrosus. Chemical internals were induced by mechanical externals among the contributing factors of chronic discogenic pain.

Quantitative Assessment of Intervertebral Disc Composition by MRI: Sensitivity to Diurnal Variation.

Whether diurnal variation exists in quantitative MRI indices such as the T1rho relaxation time (T1ρ) of the intervertebral disc (IVD) is yet to be explored. This prospective study aimed to evaluate the diurnal variation in T1ρ, apparent diffusion coefficient (ADC), and electrical conductivity (σ) of lumbar IVD and its relationship with other MRI or clinical indices. Lumbar spine MRI, including T1ρ imaging, diffusion-weighted imaging (DWI), and electric properties tomography (EPT), was conducted on 17 sedentary workers twice (morning and evening) on the same day. The T1ρ, ADC, and σ of IVD were compared between the time points. Their diurnal variation, if any, was tested for correlation with age, body mass index (BMI), IVD level, Pfirrmann grade, scan interval, and diurnal variation in IVD height index. The results showed a significant decrease in T1ρ and ADC and a significant increase in the σ of IVD in the evening. T1ρ variation had a weak correlation with age and scan interval, and ADC variation with scan interval. Diurnal variation exists for the T1ρ, ADC, and σ of lumbar IVD, which should be accounted for in image interpretation. This variation is thought to be due to diurnal variations in intradiscal water, proteoglycan, and sodium ion concentration.

Assessment of quality of life, pain level and disability outcomes after lumbar discectomy.

This study aimed to assess the quality of life of 113 Caucasian patients with intervertebral disc (IVD) degeneration of the lumbosacral (L/S) spine who qualified for microdiscectomy during a 12-month period after surgery. Based on magnetic resonance imaging before the surgery, the degree of radiological advancement of the degenerative changes was determined according to the Pfirrmann grading scale from 1 to 5. To assess pain intensity, the Visual Analog Scale (VAS) was used; the Satisfaction with Life Scale (SWLS) was used to evaluate quality of life; and to assess the degree of ability, the Oswestry Low Back Pain Disability Questionnaire (ODI) was employed. The level of pain, assessed using the VAS, significantly changed in the months following the surgery, with the highest values noted before surgery and the lowest a year after. In turn, the results of the SWLS questionnaire revealed a significant increase in satisfaction with life in the subsequent stages of the study. The conducted correlation analysis revealed significant dependencies in terms of quality of life in regard to pain as well as degree of disability. The level of pain and degree of disability were closely related to the degree of radiological advancement of degenerative changes according to the Pfirrmann grading scale.

A real-world analysis of hybrid CDA and ACDF compared to multilevel ACDF.

BACKGROUND: Multilevel anterior cervical discectomy and fusion (mACDF) is the gold standard for multilevel spinal disease; although safe and effective, mACDF can limit regular spinal motion and contribute to adjacent segment disease (ASD). Hybrid surgery, composed of ACDF and cervical disc arthroplasty, has the potential to reduce ASD by retaining spinal mobility. This study examined the safety of hybrid surgery by utilizing administrative claims data to compare real-world rates of subsequent surgery and post-procedural hospitalization within populations of patients undergoing hybrid surgery versus mACDF for multilevel spinal disease. METHODS: This observational, retrospective analysis used the MarketScan Commercial and Medicare Database from July 2013 through June 2020. Propensity score matched cohorts of patients who received hybrid surgery or mACDF were established based on the presence of spinal surgery procedure codes in the claims data and followed over a variable post-period. Rates of subsequent surgery and post-procedural hospitalization (30- and 90-day) were compared between hybrid surgery and mACDF cohorts. RESULTS: A total of 430 hybrid surgery patients and 2,136 mACDF patients qualified for the study; average follow-up was approximately 2 years. Similar rates of subsequent surgery (Hybrid: 1.9 surgeries/100 patient-years; mACDF: 1.8 surgeries/100 patient-years) were observed for the two cohorts. Hospitalization rates were also similar across cohorts at 30 days post-procedure (Hybrid: 0.67% hospitalized/patient-year; mACDF: 0.87% hospitalized/patient-year). At 90 days post-procedure, hybrid surgery patients had slightly lower rates of hospitalization compared to mACDF patients (0.23% versus 0.42% hospitalized/patient-year; p < 0.05). CONCLUSIONS: Findings of this real-world, retrospective cohort study confirm prior reports indicating that hybrid surgery is a safe and effective intervention for multilevel spinal disease which demonstrates non-inferiority in relation to the current gold standard mACDF. The use of administrative claims data in this analysis provides a unique perspective allowing the inclusion of a larger, more generalizable population has historically been reported on in small cohort studies.

Eficacia y seguridad del espaciador intervertebral cervical con sistema de bloqueo de anclaje en pacientes adultos con enfermedad degenerativa del disco cervical con mielopatía y/o radiculopatía que no responden al tratamiento conservador / Efficacy and safety of the cervical intervertebral spacer with anchor locking system in adult patients with degenerative cervical disc disease with myelopathy and/or radiculopathy who do not respond to conservative treatment

ANTECEDENTES: En el marco de la metodología ad hoc para evaluar solicitudes de tecnologías sanitarias, aprobada mediante Resolución de Instituto de Evaluación de Tecnologías en Salud e Investigación N° 111-IETSI-ESSALUD-2021 y ampliada mediante Resolución de Instituto de Evaluación de Tecnologías en Salud e Investigación N° 97-IETSI-ESSALUD2022, se ha elaborado el presente dictamen preliminar sobre la evaluación de la eficacia y seguridad del espaciador intervertebral cervical con sistema de bloqueo de anclaje en pacientes adultos con enfermedad degenerativa del disco cervical con mielopatía y/o radiculopatía que no responden al tratamiento conservador. ASPECTOS GENERALES: La enfermedad degenerativa del disco cervical es una causa muy frecuente de dolor de cuello a nivel mundial (Kazeminasab et al., 2022). Su etiología es multifactorial, siendo el envejecimiento el factor más relevante, donde el proceso degenerativo puede ..comenzar desde la segunda década de vida pasando por fases conocidas como disfunción, inestabilidad y estabilización hasta llegar a la senectud (Fakhoury & Dowling, 2022). De esta forma, se han reportado prevalencias de casi 30 % en menores de 50 años y cerca de 90 % en mayores de 80 años (Teraguchi et al., 2014). La degeneración cervical puede resultar en mielopatía y/o radiculopatía cervical. La mielopatía se refiere a la compresión o afección de la médula espinal a nivel del canal espinal, mientras que la radiculopatía se traduce en la compresión o afección de una o varias de sus raíces cervicales. La compresión suele ser debido a una hernia discal, presencia de osteofitos, masas adyacentes, espondilosis o estenosis congénita del canal espinal (McCartney et al., 2018). La incidencia de ambas han sido previamente reportadas, con 4 casos de mielopatía cervical por 100 000 personas-año (Nouri et al., 2015), y 107.3 casos de radiculopatía cervical en varones y 63.5 en mujeres por 100 000 personas-año (Radhakrishnan et al., 1994). METODOLOGÍA: Se realizó una búsqueda bibliográfica exhaustiva con el objetivo de identificar la mejor evidencia sobre la eficacia y seguridad del espaciador intervertebral cervical con sistema de bloqueo de anclaje en pacientes adultos con enfermedad degenerativa del disco cervical con mielopatía y/o radiculopatía, que no responden al tratamiento conservador. La búsqueda bibliográfica se llevó a cabo en las bases de datos PubMed, The Cochrane Library, Web of Science y LILACS. Además, se realizó una búsqueda manual en Google y dentro de las páginas web pertenecientes a grupos que realizan evaluaciones de tecnologías sanitarias (ETS) y guías de práctica clínica (GPC), incluyendo el Centro Nacional de Excelencia Tecnológica en Salud (CENETEC), National Institute for Health and Care Excellence (NICE), la Agency for Healthcare Research and Quality's (AHRQ), Scottish Intercollegiate Guidelines Network (SIGN), The Guidelines International Network (GIN), National Health and Medical Research Council (NHMRC), Base Regional de Informes de Evaluación de Tecnologías en Salud de las Américas (BRISA), Comissáo Nacional de Incorporacáo de Tecnologias no Sistema Único de Saúde (CONITEC), Instituto de Evaluación Tecnológica en Salud (IETS), Instituto de Efectividad Clínica y Sanitaria (IECS), Scottish Medicines Consortium (SMC), Canadian Agency for Drugs and Technologies in Health (CADTH), Instituto de Calidad y Eficiencia en la Atención de la Salud (IQWiG, por sus siglas en alemán), y Hauté Autorité de Santé (HAS). Asimismo, se realizó una búsqueda de GPC en las páginas web de las principales sociedades o instituciones especializadas el manejo de patologías de la médula espinal, tales como: Spine Intervention Society (SIS), Spine Society of Australia (SSA) y la Asia Pacific Spine Society (APOA). Finalmente, se realizó una búsqueda de estudios en curso aún no publicados en las páginas web de ClinicalTrials.govy la International Clinical Trials Registry Platform. RESULTADOS: La búsqueda bibliográfica se llevó a cabo el 18 de octubre de 2022. Se incluyeron dos GPC (Fehlings et al., 2017; Latka et al., 2016) que tuvieron recomendaciones relacionadas al procedimiento, pero no al dispositivo; una RS con metaanálisis en red (NMA, por sus siglas en inglés "Network meta-analysis") (Xu et al., 2020) que realizó comparaciones indirectas de la intervención y comparador de la pregunta PICO planteada con otros dispositivos que no formaron parte la presente ETS, motivo por el que se decidió identificar ECA. Es así que también se incluyó un ECA (Zhou et al., 2020) que no evaluó todos los desenlaces planteados en la pregunta PICO (tiempo quirúrgico y eventos adversos), por lo que se decidió incluir EO que contribuyan con estos desenlaces. De esta forma se incluyeron dos EO (Wang et al., 2015; Zhou et al., 2018) que tuvieron un diseño tipo cohorte retrospectiva. CONCLUSIÓN: Por lo expuesto, el Instituto de Evaluación de Tecnologías en Salud e InvestigaciónIETSI aprueba el uso del espaciador intervertebral cervical con sistema de bloqueo de anclaje como tratamiento para los pacientes adultos con enfermedad degenerativa del disco cervical con mielopatía y/o radiculopatía que no responden al tratamiento conservador.

Cost effectiveness of implanting a prosthesis after anterior cervical discectomy for radiculopathy: results of the NECK randomized controlled trial.

BACKGROUND CONTEXT: In the treatment of cervical radiculopathy due to a herniated disc, potential surgical treatments include: anterior cervical discectomy (ACD), ACD and fusion using a cage (ACDF), and anterior cervical disc arthroplasty (ACDA). Previous publications yielded comparable clinical and radiological outcome data for the various implants, but research on their comparative costutility has been inconclusive. PURPOSE: To evaluate the cost utility of ACD, ACDF, and ACDA. STUDY DESIGN: Cost-utility analysis. PATIENT SAMPLE: About 109 patients with cervical radiculopathy randomized to undergo ACD, ACDF, or ACDA as part of the NEtherlands Cervical Kinetics trial. OUTCOME MEASURES: Quality-adjusted life-years (QALYs) estimated from patient-reported utilities using the EuroQol-5D questionnaire and EuroQol Visual Analogue Scale (EQ VAS), measured at baseline, 2, 4, 8, 12, 26, 52, and 104 weeks postprocedure. Societal costs including admissions to hospital (related and otherwise), GP visits, specialist visits, physical therapy, medications, home care, aids, informal care, productivity losses, and out of pocket condition-related expenses. METHODS: The cost utility of the competing strategies over 1 and 2 years was assessed following a net benefit (NB) approach, whereby the intervention with the highest NB among competing strategies is preferred. Cost effectiveness acceptability curves were produced to reflect the probability of each strategy being the most cost effective across various willingness-to-pay (WTP) thresholds. Five sensitivity analyses were conducted to assess the robustness of results. RESULTS: ACDF was more likely to be the most cost-effective strategy at WTP thresholds of €20,000 to 50,000/QALY in all but one of the analyses. The mean QALYs during the first year were 0.750, 0.817, and 0.807 for ACD, ACDF, and ACDA, respectively, with no significant differences between groups. Total healthcare costs over the first year were significantly higher for ACDA, largely due to the higher surgery and implant costs. The total societal costs of the three strategies were €12,173 for ACD, €11,195 for ACDF, and €13,746 for ACDA, with no significant differences between groups. CONCLUSION: Our findings demonstrate that ACDF is likely to be more cost-effective than ACDA or ACD at most WTP thresholds, and this conclusion is robust to most sensitivity analyses conducted. It is demonstrated that the difference in costs is mainly caused by the initial surgical costs and that there are only minimal differences in other costs during follow-up. Since clinical data are comparable between the groups, it is to the judgment of the patient and surgeon which intervention is applied.

Cervical Disc Arthroplasty Usage Has Leveled Out From 2010 to 2021.

STUDY DESIGN: Descriptive epidemiologic study. OBJECTIVE: To compare trends in utilization and predictive factors for single-level cervical disc arthroplasty (CDA) relative to anterior cervical discectomy and fusion (ACDF) over the years. BACKGROUND: CDA is an alternative to ACDF for the treatment of cervical spine pathologies. With both procedures performed for similar indications, controversy on best practices exists. MATERIALS AND METHODS: Patients who underwent single-level CDA or ACDF were identified in the 2010 through 2021 PearlDiver M151Ortho data set. The yearly number of CDAs performed and proportionality was assessed. Predictive patient factors for undergoing CDA as opposed to ACDF were determined. Kaplan Meyer survival analysis with an endpoint of cervical spine reoperation compared 5-year outcomes between CDA and ACDF. RESULTS: From 2010 to 2021, 19,301 single-level CDAs and 181,476 single-level ACDFs were identified. The proportional utilization of CDA relative to ACDF increased from 4.00% in 2010 to 14.15% in 2018 ( P < 0.0001), after which there was a plateau between 2018 and 2021 where proportional utilization was 14.47% ( P = 0.4654). Multivariate analysis identified several predictors of undergoing CDA rather than ACDF, including: younger age [odds ratio (OR) per decade decrease: 1.72], having surgery performed in the Midwest, Northeast, or West (relative to South, OR: 1.16, 1.13, 2.26, respectively), having Commercial insurance (relative to Medicare, OR: 1.75), and having surgery performed by an orthopedic surgeon (relative to a neurological surgeon, OR: 1.54) ( P < 0.0001 for each). There was no statistically significant difference in 5-year survival to further cervical spine surgery between CDA and ACDF at 5 years (97.6% vs. 97.7%, P = 0.4249). CONCLUSIONS: Although the use of CDA relative to ACDF rose from 2010 to 2018, its use has subsequently plateaued between 2018 and 2021 and remained a relatively low percentage of the single-level anterior cervical surgeries performed (14.47% in 2021). The causes for such changes in the trend are unclear.

Association Between Hypercholesterolemia and Neck Pain in a Cross-sectional Population-based Study.

STUDY DESIGN: Retrospective cross-sectional analysis. SUMMARY OF BACKGROUND DATA: Degenerative changes are a major contributor to chronic neck pain. According to the vascular hypothesis of disk disease, atherosclerosis of the segmental arteries contributes to ischemia of the lumbar disks and resulting degenerative changes. Prior studies have demonstrated an association between atherosclerotic risk factors and lumbar degenerative disease. Similarly, atherosclerosis may contribute to cervical disk degeneration. Cardiovascular disease is associated with the development of atherosclerosis, particularly in small vessels to the cervical spine. Hypercholesterolemia is a major contributor to the morbidity associated with cardiovascular disease. This study aims to examine the relationship between hypercholesterolemia and neck pain. MATERIALS AND METHODS: Analysis was focused on the respondents to neck pain items of the standardized questionnaire. Odds ratios were calculated, and logistic regression analyses adjusted for demographic, education, and mental health conditions. RESULTS: There were 30,461 participants in the 2018 Medicare Expenditure Panel Survey (MEPS) survey. Of those, 1049 (3.4%) subjects responded to presence of a diagnosis of cervical disorders with neck pain. Mean age of respondents was 62.6±16.1. Overall prevalence of neck pain was 21.1%. Prevalence of neck pain was similar by age, sex, education level, and occupation ( P >0.05 for each). Neck pain was more prevalent in white race and lower total family income ( P <0.05). Current everyday smokers also had higher prevalence of neck pain ( P <0.05). Logistic regression analysis revealed a higher prevalence of neck pain in those with hypercholesterolemia after controlling for relevant covariates (adjusted odds ratio=1.54, 95% CI: 1.08-2.22, P =0.018). CONCLUSIONS: Subjects with hypercholesterolemia were 54% more likely to have neck pain after controlling for confounders. This suggests that hypercholesterolemia has a role to play in degeneration of the cervical spine. Therefore, prevention and proper management of high cholesterol may curtail the development and progression of degenerative cervical disk disease and thus, neck pain.

Assessment of the correlation between clinical and radiological outcomes in patients suffering from mild to moderate cervical spine dysfunction symptoms: a prospective study.

BACKGROUND: Neck pain and cervical disc degeneration (CDD) are common findings. Valid data on correlation between clinical scores and radiological grade of CDD in patients with mild to moderate clinical disability are not available. The study has been designed to investigate the correlation between clinical and radiological outcomes in these patients. METHODS: A cohort of 150 patients who suffered from mild to moderate cervical spine dysfunction symptoms from September 2020 to May 2021 was enrolled. We evaluated functional status using Japanese Orthopaedic Association scores (JOA), the visual analog scale, and the Neck Disability Index. We assessed the CDD with magnetic resonance imaging-based grading systems. We analyzed relationships between radiological grades of CDD and clinical symptoms along with demographic data. RESULTS: One hundred thirteen patients [mean age 44.78, 78 (69%) females] were finally included. CDD occurred most at the C5-C6 level, with 56.93% of higher grade III from Miyazaki. The grades of Miyazaki (P < 0.05) and the scores of Nakashima (P < 0.05) were positively correlated with the duration of symptoms, and the severity of the CDD increased with aging (P < 0.01). Moreover, we correlated patients' JOA scores with the current scoring and grading systems, especially the grades of Miyazaki (P < 0.01) and the scores of Nakashima (P < 0.01). CONCLUSION: Increasing grades of CDD paralleled decreasing JOA scores in the population studied.

Primary and Revision Cervical Disc Arthroplasty from 2010-2020: Patient Demographics, Utilization Trends, and Health Care Reimbursements.

OBJECTIVES: Despite lack of nationwide Medicare coverage by the Centers for Medicare and Medicaid Services, the utilization of cervical disc arthroplasty (CDA) has risen in popularity. The purpose was to compare primary and revision CDA from 2010 to 2020 with respect to: (1) utilization trends, (2) patient demographics, and (3) health care reimbursements. METHODS: Using the PearlDiver database, we studied patients undergoing primary and revision CDA for degenerative cervical spine pathology from 2010 to 2020. Endpoints of the study were to compare patient demographics (including Elixhauser Comorbidity Index [ECI]), annual utilization trends, length of stay (LOS), and reimbursements. Chi-square analyses compared patient demographics. t tests compared LOS and reimbursements. A linear regression was used to evaluate for trends in procedural volume over time. P values <0.05 were considered statistically significant. RESULTS: In total, 15,306 patients underwent primary (n = 14,711) or revision CDA (n = 595). Patients undergoing revisions had a greater comorbidity burden (mean ECI 4.16 vs. 2.91; P < 0.0001). From 2010 to 2020, primary CDA utilization increased by 413% (447 vs. 2297 procedures; P < 0.001); comparatively, revision CDA utilization increased by 141% (32 vs. 77 procedures; P < 0.001). Mean LOS was greater for revision cases (1.37 vs. 3.30 days, P < 0.001). Reimbursements for revisions were higher on the day of surgery ($5585 vs. $13,692) and within 90 days of surgery ($7031 vs. $19,340), all P < 0.0001. CONCLUSIONS: There is a high rate of annual growth in CDA utilization and revision CDA in the United States. Reimbursements for revision CDA were more than double primary cases.

Research protocol: Cervical Arthroplasty Cost Effectiveness Study (CACES): economic evaluation of anterior cervical discectomy with arthroplasty (ACDA) versus anterior cervical discectomy with fusion (ACDF) in the surgical treatment of cervical degenerative disc disease - a randomized controlled trial.

INTRODUCTION: To date, there is no consensus on which anterior surgical technique is more cost-effective in treating cervical degenerative disc disease (CDDD). The most commonly used surgical treatment for patients with single- or multi-level symptomatic CDDD is anterior cervical discectomy with fusion (ACDF). However, new complaints of radiculopathy and/or myelopathy commonly develop at adjacent levels, also known as clinical adjacent segment pathology (CASP). The extent to which kinematics, surgery-induced fusion, natural history, and progression of disease play a role in the development of CASP remains unclear. Anterior cervical discectomy with arthroplasty (ACDA) is another treatment option that is thought to reduce the incidence of CASP by preserving motion in the operated segment. While ACDA is often discouraged, as the implant costs are higher while the clinical outcomes are similar to ACDF, preventing CASP might be a reason for ACDA to be a more cost-effective technique in the long term. METHODS AND ANALYSIS: In this randomized controlled trial, patients will be randomized to receive ACDF or ACDA in a 1:1 ratio. Adult patients with single- or multi-level CDDD and symptoms of radiculopathy and/or myelopathy will be included. The primary outcome is cost-effectiveness and cost-utility of both techniques from a healthcare and societal perspective. Secondary objectives are the differences in clinical and radiological outcomes between the two techniques, as well as the qualitative process surrounding anterior decompression surgery. All outcomes will be measured at baseline and every 6 months until 4 years post-surgery. DISCUSSION: High-quality evidence regarding the cost-effectiveness of both ACDA and ACDF is lacking; to date, there are no prospective trials from a societal perspective. Considering the aging of the population and the rising healthcare costs, there is an urgent need for a solid clinical cost-effectiveness trial addressing this question. TRIAL REGISTRATION: ClinicalTrials.gov NCT04623593. Registered on 29 September 2020.

Dynamic elastic modulus assessment of the early degeneration model of an intervertebral disc in cynomolgus monkeys with one strike loading.

OBJECTIVE: Disc degeneration has long been associated with excessive mechanical loading or acute disc injury. Our goal is to perform a shock load on the functional units of the cynomolgus monkey intervertebral disc and analyze the degree of degeneration of the intervertebral disc through image analysis and comprehensive analysis. The organ model establishes a standard organ culture model and a non-invasive biomechanical evaluation protocol close to the early degeneration of the human intervertebral disc. METHODS: After modeling, the cynomolgus monkey intervertebral discs were collected and loaded into the dynamic mechanical culture system. The physiological group was loaded with 10% high compressive deformation load for one second, the injury group was punctured with annulus fibrosus, the model group was loaded with 20-50% high compressive deformation, and the nutritional components were a high-glucose group and low-glucose group. After day 3 (short term) and day 10 (long term), samples were collected to analyze cell viability, histomorphology, image analysis for imaging and biomechanical changes. RESULTS: Both the injury group and the 30-50% strain model group showed signs of early degeneration, including decreased instantaneous compressive stiffness, percent change in gray value, decreased cell viability, AF fissure, and percent increase in dynamic elastic modulus. The glucose-restricted group also showed signs of early disc degeneration in long-term cultures. CONCLUSION: This study shows that a single shock load can induce early degeneration of healthy cynomolgus monkey intervertebral discs, and 30% strain may be the nociceptive threshold for early degeneration of healthy intervertebral discs. More importantly, a non-invasive biomechanical evaluation scheme of Percentage change in dynamic modulus of elasticity is established, which solves the key scientific problem of how to non-invasively, quantitatively and sensitively detect the development process of early intervertebral disc degeneration and its degree of degeneration in an in vitro organ model.

Single-cell assessment of the modulation of macrophage activation by ex vivo intervertebral discs using impedance cytometry.

Measurement of macrophage activation and its modulation for immune regulation is of great interest to arrest inflammatory responses associated with degeneration of intervertebral discs that cause chronic back pain, and with transplants that face immune rejection. Due to the phenotypic plasticity of macrophages that serve multiple immune functions, the net disease outcome is determined by a balance of subpopulations with competing functions, highlighting the need for single-cell methods to quantify heterogeneity in their activation phenotypes. However, since macrophage activation can follow several signaling pathways, cytometry after fluorescent staining of markers with antibodies does not often provide dose-dependent information on activation dynamics. We present high throughput single-cell impedance cytometry for multiparametric measurement of biophysical changes to individual macrophages for quantifying activation in a dose and duration dependent manner, without relying on a particular signaling pathway. Impedance phase metrics measured at two frequencies and the electrical diameter from impedance magnitude at lower frequencies are used in tandem to benchmark macrophage activation by degenerated discs against that from lipopolysaccharide stimulation at varying dose and duration levels, so that reversal of the activation state by curcumin can be ascertained. This label-free single-cell measurement method can form the basis for platforms to screen therapies for inflammation, thereby addressing the chronic problem of back pain.

Comparison of MRI T1, T2, and T2* mapping with histology for assessment of intervertebral disc degeneration in an ovine model.

An easy, reliable, and time-efficient standardized approach for assessing lumbar intervertebral disc (IVD) degeneration with relaxation times measurements in pre-clinical and clinical studies is lacking. This prospective study aims to determine the most appropriate method for lumbar IVD degeneration (IDD) assessment in sheep by comparing three quantitative MRI sequences (variable-flip-angle T1 mapping, and multi-echo T2 and T2* mapping), correlating them with Pfirrmann grading and histology. Strong intra- and interrater agreements were found for Nucleus pulposus (NP) regions-of-interest (ROI). T1, T2, and T2* mapping correlated with Pfirrmann grading and histological scoring (p < 0.05) except for the most ventral rectangular ROI on T2 maps. Correlations were excellent for all of the T1 ROIs and the T2* NP ROIs. Highly significant differences in T1 values were found between all Pfirrmann grades except between grades I/II and between grades III/IV. Significant differences were identified in the T2 and the T2* values between all grades except between grades I/III. T1, T2, and T2* relaxation times measurements of the NP are an accurate and time-efficient tool to assess lumbar IDD in sheep. Variable-flip-angle T1 mapping may be further considered as a valuable method to investigate IDD and to assess the efficacy of regenerative treatments in longitudinal studies.

Single-Segment Lumbar Intervertebral Disc Nucleus Excision on the Stability of Lumbar Segmental Sagittal Plane.

At present, lumbar disc herniation has become a problem that plagues people's health, life safety, and social and economic development. Among them, the research of lumbar disc nucleus pulposus tissue is the focus of the treatment of lumbar disc diseases. At present, the treatment methods of lumbar disc herniation are divided into conservative treatment and surgical treatment, among which surgical treatment can be divided into open surgery and minimally invasive surgery. Surgical treatment to remove the nucleus pulposus from the disc by fenestration includes conventional ablation of the nucleus pulposus and microscopic lumbar discs. This treatment is effective, but it has a great impact on the stabilization mechanism of the spine, with large soft tissue damage and large blood loss, which can easily cause nerve damage and postdural adhesions. At the same time, single-segment lumbar discectomy has also been gradually applied to the treatment of this disease. Under this, this paper studies single-segment lumbar disc nucleus pulposus resection. The lumbar nucleus resection is performed in a single segment in the physiological load area, which can greatly ensure the stability of the sagittal plane of the lumbar spine. In order to better understand the postoperative rehabilitation and clinical effects of single-segment lumbar discectomy, as well as the changes in the sagittal plane of the lumbar vertebrae before and after the operation, so as to provide a reference for further improving the quality of life of patients, this paper uses questionnaire survey and data analysis methods. According to the results of the questionnaire survey, compared with other operations, single-segment lumbar discectomy is more stable in the sagittal plane of the lumbar spine within the physiological load range, and there is less displacement. The displacement may be caused or influenced by different kinds of factors such as heavy loads or manual labor. In addition, most patients have less abnormal pain after surgery, indicating that the surgery has a certain effect on the treatment of the disease, and there are fewer abnormalities after surgery.