Osteoporosis Treatment and Outcomes in Patients Undergoing Adult Spinal Deformity Surgery.

INTRODUCTION: Adult spinal deformity (ASD) treatment for patients with osteoporosis presents a unique challenge for spine surgeons, particularly with ensuring adequate fixation and correction during surgery and due to the risk of treatment failure and complications thereafter. Osteoporosis is characterized by low bone mineral density (BMD) which may increase the risk for fractures. Approximately 12.6% of all adults over 50 years old in the United States are affected by osteoporosis, and the prevalence is predicted to increase with the aging population.1 ASD patients experience substantially higher rates of osteoporosis compared to the general population.2,3 One study discovered an osteoporosis prevalence of nearly 33% in a cohort of ASD patients undergoing long spinal fusion at two academic medical centers, with slightly over one- third of those patients receiving osteoporosis pharmacotherapy prior to surgery.3 Similarly, patients with osteoporosis experience ASD at higher rates than the general population, with one study finding that 9.5% of patients with osteoporosis suffer from ASD symptoms.3 Gupta et al. discovered that obtaining a DEXA scan of the forearm in addition to the hip allowed physicians to detect an additional 17% incidence of osteoporosis in ASD patients, suggesting that osteoporosis may be missed when there is only one DEXA scan available.4In addition to being potentially underdiagnosed and undertreated, ASD patients with osteoporosis experience higher rates of post-surgical complications. Pseudarthrosis, or nonunion after spinal fusion, is a painful and potentially debilitating complication following ASD surgery that ultimately requires additional surgical correction. Proximal junctional kyphosis (PJK), which is defined as proximal junctional sagittal Cobb angle ≥ 10° and at least 10° greater than the preoperative measurement, is another complication of ASD surgery.5 Though this condition may be clinically silent and manifest purely as a radiographic diagnosis, it is often a precursor to proximal junctional failure (PJF), a more severe form of PJK that ultimately increases the risk for intractable pain, neurological deficit, and revision surgery.6 ASD patients with osteoporosis experience significantly higher rates of pseudarthrosis, PJK, PJF, and postoperative fractures, as well as other forms of instrumentation failure requiring additional surgical treatment.7-11 This ultimately increases the pain, emotional burden, and morbidity experienced by patients. There is currently conflicting data regarding the impact of perioperative osteoporosis pharmacotherapy on outcomes in ASD patients. Bisphosphonates are considered first-line treatment for osteoporosis, though alternatives such as teriparatide, denosumab, and calcitonin may be used as well.12 Multiple studies have found that preoperative bisphosphonate treatment did not affect lumbar fusion nonunion rates.13,14 In contrast, a meta-analysis of randomized control trials found that postoperative bisphosphonates had no effect on lumbar fusion rates but did significantly reduce the risk of vertebral compression fracture (VCF) and pedicle screw loosening at 12-month follow-up.15 Prophylactic teriparatide treatment has been associated with improved BMD and lower incidence of PJK type-2 in osteoporosis patients who underwent ASD surgery.16 Evidence for perioperative treatment of teriparatide as a preventative step to increase fusion rates and reduce PJK and PJF is strongest.17 However, the percentage of ASD patients who are actually being treated perioperatively with these medications requires further evaluation, and a comparison of outcomes with osteoporosis and non-osteoporosis counterparts has yet to be explored. The purpose of this study was to evaluate the prevalence and treatment of osteoporosis among patients undergoing long spinal fusion for ASD, as well as compare the impact of osteoporosis treatment on surgical and radiographic outcomes following fusion surgery. Additionally, we sought to examine the differences in radiographic outcomes of osteoporotic patients receiving various pharmacologic regimens such as monotherapy vs combination therapy.

An old unknown: 40 years of crayfish plague monitoring in Switzerland, the water tower of Europe.

The oomycete Aphanomyces astaci is the causative agent of crayfish plague, a disease threatening susceptible freshwater crayfish species in Europe. To detect its spatiotemporal occurrence in Switzerland, we reviewed (1) the literature regarding occurrence of crayfish plague and North American crayfish carrier species and (2) the necropsy report archive of the Institute for Fish and Wildlife Health (FIWI) from 1968 to 2020. In the past, crayfish plague was diagnosed through several methods: conventional PCR, culture, and histology. When available, we re-evaluated archived Bouin's or formalin-fixed, paraffin-embedded samples collected during necropsies (1991-2020) with a recently published quantitative PCR. Literature research revealed putative reports of crayfish plague in Switzerland between the 1870s and 1910s and the first occurrence of three North American crayfish species between the late 1970s and 1990s. Finally, 54 (28.1%) cases were classified as positive and 9 (4.7%) cases as suspicious. The total number of positive cases increased by 14 (14.7%) after re-evaluation of samples. The earliest diagnosis of crayfish plague was performed in 1980 and the earliest biomolecular confirmation of A. astaci DNA dated 1991. Between 1980-1990, 1991-2000 and 2001-2010 crayfish plague spread from one to two and finally three catchment basins, respectively. Similar to other European countries, crayfish plague has occurred in Switzerland in two waves: the first at the end of the 19th and the second at the end of the 20th century in association with the first occurrence of North American crayfish species. The spread from one catchment basin to another suggests a human-mediated pathogen dispersal.

Analysis of a European general wildlife health surveillance program: Chances, challenges and recommendations.

In a One Health perspective general wildlife health surveillance (GWHS) gains importance worldwide, as pathogen transmission among wildlife, domestic animals and humans raises health, conservation and economic concerns. However, GWHS programs operate in the face of legal, geographical, financial, or administrative challenges. The present study uses a multi-tiered approach to understand the current characteristics, strengths and gaps of a European GWHS that operates in a fragmented legislative and multi-stakeholder environment. The aim is to support the implementation or improvement of other GWHS systems by managers, surveillance experts, and administrations. To assess the current state of wildlife health investigations and trends within the GWHS, we retrospectively analyzed 20 years of wildlife diagnostic data to explore alterations in annual case numbers, diagnosed diseases, and submitter types, conducted an online survey and phone interviews with official field partners (hunting administrators, game wardens and hunters) to assess their case submission criteria as well as their needs for post-mortem investigations, and performed in-house time estimations of post-mortem investigations to conduct a time-per-task analysis. Firstly, we found that infectious disease dynamics, the level of public awareness for specific diseases, research activities and increasing population sizes of in depth-monitored protected species, together with biogeographical and political boundaries all impacted case numbers and can present unexpected challenges to a GWHS. Secondly, we found that even a seemingly comprehensive GWHS can feature pronounced information gaps, with underrepresentation of common or easily recognizable diseases, blind spots in non-hunted species and only a fraction of discovered carcasses being submitted. Thirdly, we found that substantial amounts of wildlife health data may be available at local hunting administrations or disease specialist centers, but outside the reach of the GWHS and its processes. In conclusion, we recommend that fragmented and federalist GWHS programs like the one addressed require a central, consistent and accessible collection of wildlife health data. Also, considering the growing role of citizen observers in environmental research, we recommend using online reporting systems to harness decentrally available information and fill wildlife health information gaps.

Detection of novel RNA viruses in wild noble crayfish (Astacus astacus): A virome analysis in Swiss water bodies.

European native crayfish populations are undergoing a strong decline due to environmental factors and the introduction of highly competitive non-native species. Pathogens are an additional threat to native crayfish. However, aside from the crayfish plague, other infectious diseases are still widely unknown. This study aimed to investigate viruses present in seven populations of wild noble crayfish (Astacus astacus) in Switzerland, through high-throughput sequencing. Sequence analysis revealed the presence of 11 novel RNA viruses (one bunya-like, four hepe-like, two dicistro-like, three picorna-like, and one permutotetra-like) in the samples. The discovery of a novel bunya-like virus in noble crayfish without associated mortality or macroscopical alterations is of particular interest since it is closely related to the bunya-like brown spot virus, a virus described in 2019 from diseased native white-clawed crayfish (Austropotamobius pallipes) during a mass mortality event in France. It seems that these two closely related viruses have very different impacts on their respective hosts, raising the need for further investigations on virulence factors and host susceptibility towards these viruses. This study provides a basis for future investigations, permitting to gradually fill the knowledge gap in crayfish viral diseases.

Laminoplasty versus laminectomy with fusion for treating multilevel degenerative cervical myelopathy.

Background: Laminectomy with fusion (LF) and laminoplasty (LP) are common posterior decompression procedures used to treat multilevel degenerative cervical myelopathy (DCM). There is debate on their relative efficacy and safety for treatment of DCM. The goal of this study is to examine outcomes and costs of LF and LP procedures for DCM. Methods: This is a retrospective review of adult patients (<18) at a single center who underwent elective LP and LF of at least 3 levels from C3-C7. Outcome measures included operative characteristics, inpatient mobility status, length of stay, complications, revision surgery, VAS neck pain scores, and changes in radiographic alignment. Oral opioid analgesic needs and hospital cost comparison were also assessed. Results: LP cohort (n=76) and LF cohort (n=59) reported no difference in neck pain at baseline, 1, 6, 12, and 24 months postoperatively (p>.05). Patients were successfully weaned off opioids at similar rates (LF: 88%, LP: 86%). Fixed and variable costs respectively with LF cases hospital were higher, 15.7% and 25.7% compared to LP cases (p=.03 and p<.001). LF has a longer length of stay (4.2 vs. 3.1 days, p=.001). Wound-related complications were 5 times more likely after LF (13.6% vs. 5.9%, RR: 5.15) and C5 palsy rates were similar across the groups (LF: 11.9% LP: 5.6% RR: 1.8). Ground-level falls requiring an emergency department visit were more likely after LF (11.9% vs. 2.6%, p=.04). Conclusions: When treating multilevel DCM, LP has similar rates of new or increasing axial neck pain compared to LF. LF was associated with greater hospital costs, length of stay, and complications compared to LP. LP may in fact be a less morbid and more cost-effective alternative to LF for patients without cervical deformity.

Sociodemographic Characteristics of Patients Undergoing Surgery for Metastatic Disease of the Spine.

INTRODUCTION: Some patients, particularly those who are socioeconomically deprived, are diagnosed with primary and/or metastatic cancer only after presenting to the emergency department. Our objective was to determine sociodemographic characteristics of patients undergoing surgery for metastatic spine disease at our institution. METHODS: This retrospective case series included patients 18 years and older who presented to the emergency department with metastatic spine disease requiring surgery. Demographics and survival data were collected. Sociodemographic characteristics were estimated using the Social Deprivation Index (SDI) and Area Deprivation Index (ADI) for the state of California. Univariate log-rank tests and Kaplan-Meier curves were used to assess differences in survival for predictors of interest. RESULTS: Between 2015 and 2021, 64 patients underwent surgery for metastatic disease of the spine. The mean age was 61.0 ± 12.5 years, with 60.9% being male (n = 39). In this cohort, 89.1% of patients were non-Hispanic (n = 57), 71.9% were White (n = 46), and 62.5% were insured by Medicare/Medicaid (n = 40). The mean SDI and ADI were 61.5 ± 28.0 and 7.7 ± 2.2, respectively. 28.1% of patients (n = 18) were diagnosed with primary cancer for the first time while 39.1% of patients (n = 25) were diagnosed with metastatic cancer for the first time. During index hospitalization, 37.5% of patients (n = 24) received palliative care consult. The 3-month, 6-month, and all-time mortality rates were 26.7% (n = 17), 39.5% (n = 23), and 50% (n = 32), respectively, with 10.9% of patients (n = 7) dying during their admission. Payor plan was significant at 3 months ( P = 0.02), and palliative consultation was significant at 3 months ( P = 0.007) and 6 months ( P = 0.03). No notable association was observed with SDI and ADI in quantiles or as continuous variables. DISCUSSION: In this study, 28.1% of patients were diagnosed with cancer for the first time. Three-month and 6-month mortality rates for patients undergoing surgery were 26.7% and 39.5%, respectively. Furthermore, mortality was markedly associated with palliative care consultation and insurance status, but not with SDI and ADI. LEVEL OF EVIDENCE: Retrospective case series, Level III evidence.

Sarcoptic mange in Felidae: does Sarcoptes scabiei var. felis exist? A first molecular study.

Domestic and wild felids are considered suitable hosts for the parasitic mite Sarcoptes scabiei, and sarcoptic mange is reported in several felid species in the scientific literature. However, the historic classification of Sarcoptes mites into host-specific varieties does not include S. scabiei var. felis. It is unclear whether sarcoptic mange transmission in felids involves canids, other sympatric species, or exclusively felids. This study aimed to characterize the genetic structure of S. scabiei mites from domestic cats (Felis catus) and Eurasian lynx (Lynx lynx carpathicus), comparing them with Sarcoptes mites from sympatric domestic and wild carnivores. Ten Sarcoptes microsatellite markers were used to genotype 81 mites obtained from skin scrapings of 36 carnivores: 4 domestic cats, one dog (Canis lupus familiaris), 4 Eurasian lynx, 23 red foxes (Vulpes vulpes), and 4 grey wolves (Canis lupus lupus) from either Italy, Switzerland or France. Two genetic clusters of S. scabiei with a geographical distribution pattern were detected: mites from cats originating from Central Italy clustered with those from sympatric wolves. In contrast, all the other mites from Switzerland, France and Northern Italy clustered together. These results strengthen the previously advanced hypothesis that genetic variants of S. scabiei have a predominant geographic-related distribution with cryptic transmission patterns. These patterns may rely on the interactions between different hosts living in the same ecological niche rather than a simple infection among hosts belonging to the same taxon, reinforcing the idea that the S. scabiei historic classification into "var" might have little ongoing relevance.

Title: La gale sarcoptique chez les félidés : Sarcoptes scabiei var. felis existe-t-il ? Première étude moléculaire. Abstract: Les félidés domestiques et sauvages sont considérés comme des hôtes appropriés pour l'acarien parasite Sarcoptes scabiei, et la gale sarcoptique est signalée chez plusieurs espèces de félidés dans la littérature scientifique. Cependant, la classification traditionnelle des acariens du genre Sarcoptes en variétés spécifiques à l'hôte n'inclut pas S. scabiei var. felis. On ne sait pas si la transmission de la gale sarcoptique chez les félidés implique des canidés, d'autres espèces sympatriques ou exclusivement des félidés. Cette étude visait à caractériser la structure génétique des acariens S. scabiei des chats domestiques (Felis catus) et du lynx eurasien (Lynx lynx carpathicus), en les comparant aux Sarcoptes des carnivores domestiques et sauvages sympatriques. Dix marqueurs microsatellites de Sarcoptes ont été utilisés pour génotyper 81 acariens issus de grattages cutanés de 36 carnivores : 4 chats domestiques, un chien (Canis lupus familiaris), 4 lynx eurasiens, 23 renards roux (Vulpes vulpes) et 4 loups gris (Canis lupus lupus) d'Italie, de Suisse ou de France. Deux groupes génétiques de S. scabiei, qui suivent un modèle de distribution géographique, ont été détectés. Les acariens des chats originaires du centre de l'Italie se regroupent avec ceux des loups sympatriques. En revanche, tous les autres acariens de Suisse, de France et d'Italie du Nord sont groupés ensemble. Ces résultats renforcent l'hypothèse précédemment avancée selon laquelle les variants génétiques de S. scabiei ont une distribution géographique prédominante avec des schémas de transmission cryptiques. Ces modèles peuvent reposer sur les interactions entre différents hôtes vivant dans la même niche écologique plutôt que sur une simple transmission parmi des hôtes appartenant au même taxon, renforçant l'idée que la classification historique de S. scabiei en "var" a peu de pertinence.

A Comparison of Prognostic Models to Facilitate Surgical Decision-Making for Patients With Spinal Metastatic Disease.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: Compare the performance of and provide cutoff values for commonly used prognostic models for spinal metastases, including Revised Tokuhashi, Tomita, Modified Bauer, New England Spinal Metastases Score (NESMS), and Skeletal Oncology Research Group model, at three- and six-month postoperative time points. SUMMARY OF BACKGROUND DATA: Surgery may be recommended for patients with spinal metastases causing fracture, instability, pain, and/or neurological compromise. However, patients with less than three to six months of projected survival are less likely to benefit from surgery. Prognostic models have been developed to help determine prognosis and surgical candidacy. Yet, there is a lack of data directly comparing the performance of these models at clinically relevant time points or providing clinically applicable cutoff values for the models. MATERIALS AND METHODS: Sixty-four patients undergoing surgery from 2015 to 2022 for spinal metastatic disease were identified. Revised Tokuhashi, Tomita, Modified Bauer, NESMS, and Skeletal Oncology Research Group were calculated for each patient. Model calibration and discrimination for predicting survival at three months, six months, and final follow-up were evaluated using the Brier score and Uno's C, respectively. Hazard ratios for survival were calculated for the models. The Contral and O'Quigley method was utilized to identify cutoff values for the models discriminating between survival and nonsurvival at three months, six months, and final follow-up. RESULTS: Each of the models demonstrated similar performance in predicting survival at three months, six months, and final follow-up. Cutoff scores that best differentiated patients likely to survive beyond three months included the Revised Tokuhashi score=10, Tomita score=four, Modified Bauer score=three, and NESMS=one. CONCLUSION: We found comparable efficacy among the models in predicting survival at clinically relevant time points. Cutoff values provided herein may assist surgeons and patients when deciding whether to pursue surgery for spinal metastatic disease. LEVEL OF EVIDENCE: 4.

Factors Associated With Total Discharge Opioid Prescription Morphine Milligram Equivalent Amounts Following Primary Anterior Cervical Spine Surgery.

BACKGROUND: Opioid overuse is a substantial cause of morbidity and mortality in the United States, and orthopaedic surgeons are the third highest prescribers of opioids. Postoperative prescribing patterns vary widely, and there is a paucity of data evaluating patient and surgical factors associated with discharge opioid prescribing patterns after elective anterior cervical surgery (ACS). The purpose of this study was to evaluate the volume of postoperative opioids prescribed and factors associated with discharge opioid prescription volumes after elective ACS. METHODS: We retrospectively identified patients aged 18 years and older who underwent elective primary anterior cervical diskectomy and fusion (ACDF), cervical disk arthroplasty (CDA), or hybrid procedure (ACDF and CDA at separate levels) at a single institution between 2015 and 2021. Demographic, surgical, and opioid prescription data were obtained from patients' electronic medical records. Univariate and multivariate analyses were conducted to assess for independent associations with discharge opioid volumes. RESULTS: A total of 313 patients met inclusion criteria, including 226 (72.2%) ACDF, 69 (22.0%) CDA, and 18 (5.8%) hybrid procedure patients. Indications included radiculopathy in 63.6%, myelopathy in 19.2%, and myeloradiculopathy in 16.3%. The average age was 57.2 years, and 50.2% of patients were male. Of these, 88 (28.1%) underwent one-level, 137 (43.8%) underwent two-level, 83 (26.5%) underwent three-level, and 5 (1.6%) underwent four-level surgery. Younger age (P = 0.010), preoperative radiculopathy (P = 0.029), procedure type (ACDF, P < 0.001), preoperative opioid use (P = 0.012), and discharge prescription written by a midlevel provider (P = 0.010) were independently associated with greater discharge opioid prescription volumes. CONCLUSION: We identified wide variability in prescription opioid discharge volumes after ACS and patient, procedure, and perioperative factors associated with greater discharge opioid volumes. These factors should be considered when designing protocols and interventions to reduce and optimize postoperative opioid use after ACS.

Efficacy of Routine Intraoperative Cranio-Femoral Traction in Surgical Treatment of Adolescent Idiopathic Scoliosis Curves Measuring Between 50° and 90°.

STUDY DESIGN: Retrospective Comparative Study, Level III. OBJECTIVE: In patients with scoliosis >90°, cranio-femoral traction (CFT) has been shown to obtain comparable curve correction with decreased operative time and blood loss. Routine intraoperative CFT use in the treatment of AIS <90° has not been established definitively. This study investigates the effectiveness of intraoperative CFT in the treatment of AIS between 50° and 90°, comparing the magnitude of curve correction, blood loss, operative time, and traction-related complications with and without CFT. METHODS: 73 patients with curves less than 90° were identified, 36 without and 37 with cranio-femoral traction. Neuromuscular scoliosis and revision surgery were excluded. Age, preoperative Cobb angles, bending angles, and curve types were recorded. Surgical characteristics were analyzed including number of levels fused, estimated blood loss, operative time, major curve correction (%), and degree of postoperative kyphosis. RESULTS: Patients with traction had significantly higher preoperative major curves but no difference in age or flexibility. Lenke 1 curves had significantly shorter operative time and improvement in curve correction with traction. Among subjects with 5 to 8 levels fused, subjects with traction had significantly less EBL. Operative time was significantly shorter for subjects with 5-8 levels and 9-11 levels fused. Curves measuring 50°-75° showed improved correction with traction. CONCLUSION: Intraoperative traction resulted in shorter intraoperative time and greater correction of major curves during surgical treatment of adolescent idiopathic scoliosis less than 90°. Strong considerations should be given to use of intraoperative CFT for moderate AIS.

Description of a Sarcoptic Mange Outbreak in Alpine Chamois Using an Enhanced Surveillance Approach.

Since 1995, the Alpine chamois (Rupicapra r. rupicapra) population of the Dolomites has been affected by sarcoptic mange with considerable management concerns. In this study, 15 years (2006-2020) of passive surveillance and demographic data were analyzed in order to describe a mange outbreak. Furthermore, an enhanced passive surveillance protocol was implemented in order to evaluate the efficiency of ordinary vs. enhanced surveillance protocol in identifying dead chamois in the field and in reaching a correct diagnosis. Our results confirm the role of mange as a determining factor for chamois mortality, while stressing the importance of a wider view on the factors affecting population dynamics. The enhanced passive surveillance protocol increased the probability of carcass retrieval and identification of the cause of death; however, its adoption may be too costly if applied for long periods on a wide scale. Passive surveillance, in both ordinary and enhanced surveillance protocol, should encompass the use of other strategies in the future to study the eco-epidemiology of the disease in wild Caprinae.

Socioeconomic and geographic disparities in pediatric scoliosis surgery.

PURPOSE: To compare the population of pediatric patients undergoing surgery for scoliosis in California by gender, race, and ethnicity and identify any underlying differences in social determinants of health as measured by the child opportunity index (COI), social deprivation index (SDI), and insurance category among them. METHODS: This project extracted demographic reports including patient sex, race, zip code, insurance type, and associated diagnosis and procedure codes from the Office of Statewide Health Planning and Development (OSHPD). These data were combined with COI and SDI data, which further describe the socioeconomic environment of each patient. Census data were referenced to compare the population of patients receiving scoliosis procedures to the general population by race and ethnicity. Chi-square tests were performed for categorical data. Independent t-test and one-way analysis of variance (ANOVA) were performed for continuous data, with significance set at 0.05. RESULTS: Unfavorable SDI and COI scores were observed among males, Hispanics, and Black patients, and these patients were more likely to be covered by Medi-Cal. Length of stay was significantly higher among males and Medi-Cal recipients. CONCLUSION: The data demonstrate significant differences in social determinants of health as measured by race, ethnicity, gender, insurance type, COI, and SDI among patients ≤ 20 years undergoing surgery for idiopathic scoliosis in California. The noted differences in socioeconomic status (SES) and insurance are known and/or expected to have an impact on access to quality health care, exposing a need for future studies to determine whether COI and SDI influence patient-reported outcomes after scoliosis surgery. LEVEL OF EVIDENCE: IV.

Comparing Fusion Rates Between Fresh-Frozen and Freeze-Dried Allografts in Anterior Cervical Discectomy and Fusion.

Objective: The objective of this retrospective study is to compare the fusion rates in anterior cervical discectomy and fusion surgery using freeze-dried versus fresh-frozen allografts. Methods: The study comprised 79 patients. Fifty-one patients received freeze-dried allograft (106 total spinal levels) and 28 patients received fresh-frozen allograft (50 total spinal levels). Fusion was assessed through trabecular bridging on follow-up anterior-posterior/lateral radiographs. Trabecular bridging was assessed on the superior and inferior borders of each spinal level and given a fusion grade. Complete fusion is defined as >50% bridging between superior and inferior borders of the bone graft; union is complete fusion in <26 weeks; delayed union is complete fusion after 26 weeks; and fibrous union is <50% bridging at ≥1 borders over 52 weeks. Results: All spinal levels reached complete fusion for both graft types. Of the freeze-dried treated cervical spinal levels, 77.35% (82/106) reached union (adequate trabecular bridging within 6 months) without delay compared with 80% (35/50) for the fresh-frozen bone graft group (P = 0.85). There was no significant difference in time-to-fusion analysis and no significant association between delayed union and any patient factors. In assessing Neck Disability Index (NDI), freeze-dried allografts did show a significantly greater decrease in NDI scores at 6 months (P = 0.03). At the 1 year follow-up, improvements in NDI were consistent in both allografts (P = 0.9647). Conclusions: From this study, freeze-dried and fresh-frozen allografts showed comparable rates of union, and both allografts can be used interchangeably for anterior cervical discectomy and fusion.

Gender, Racial, and Ethnic Differences in the Utilization of Cervical Disk Replacement for Cervical Radiculopathy.

INTRODUCTION: Cervical radiculopathy (CR) is commonly treated by spine surgeons, with surgical options including anterior cervical diskectomy and fusion (ACDF) and cervical disk replacement (CDR). CDR is a motion-sparing alternative to ACDF and was approved by the US FDA in 2007. CDR utilization has increased because evidence has emerged demonstrating its long-term efficacy. Despite CDR's efficacy, studies have suggested that socioeconomic factors may influence which patients undergo CDR versus ACDF. Our objective was to determine whether gender, racial, and ethnic disparities exist in the utilization of CDR versus ACDF for CR. METHODS: Patients age ≥18 years undergoing elective CDR or ACDF for CR between 2017 and 2020 were identified in the Vizient Clinical Database. Proportions of patients undergoing CDR and ACDF, as well as their comorbidities, complications, and outcomes, were compared by sex, race, and ethnicity. Bonferroni correction was done for multiple comparisons. RESULTS: A total of 7,384 patients, including 1,427 undergoing CDR and 5,957 undergoing ACDF, were reviewed. Black patients undergoing surgical treatment of CR were less likely to undergo CDR than ACDF, had a longer length of stay, and had higher readmission rates, while Hispanic patients had higher complication rates than non-Hispanic patients. DISCUSSION: Important racial and ethnic disparities exist in CR treatment. Interventions are necessary to ensure equal access to spine care by reducing barriers, such as underinsurance and implicit bias. LEVEL OF EVIDENCE: IV (Case Series).

Phylogeography and population genetic structure of the European roe deer in Switzerland following recent recolonization.

In the early 1800s, the European roe deer (Capreolus capreolus) was probably extirpated from Switzerland, due to overhunting and deforestation. After a federal law was enacted in 1875 to protect lactating females and young, and limiting the hunting season, the roe deer successfully recovered and recolonized Switzerland. In this study, we use mitochondrial DNA and nuclear DNA markers to investigate the recolonization and assess contemporary genetic structure in relation to broad topographic features, in order to understand underlying ecological processes, inform future roe deer management strategies, and explore the opportunity for development of forensic traceability tools. The results concerning the recolonization origin support natural, multidirectional immigration from neighboring countries. We further demonstrate that there is evidence of weak genetic differentiation within Switzerland among topographic regions. Finally, we conclude that the genetic data support the recognition of a single roe deer management unit within Switzerland, within which there is a potential for broad-scale geographic origin assignment using nuclear markers to support law enforcement.

Erector Spinae Plane Blocks With Liposomal Bupivacaine for Pediatric Scoliosis Surgery.

Pain management in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion can be challenging. Various analgesic techniques are currently used, including enhanced recovery after surgery principles, spinal opioids or continuous epidural infusion, intravenous methadone, or surgical site infiltration of local anesthetic. Another recently developed technique, ultrasound-guided erector spinae plane blockade (ESPB), has been used successfully in spine surgery and may offer advantages because of its ease of placement, excellent safety profile, and opioid sparing qualities. Liposomal bupivacaine is a long-acting local anesthetic that was recently approved for infiltration and fascial plane blocks in pediatric patients of ages 6 years and older. This medication may prove to be beneficial when administered through ESPB in patients with AIS undergoing posterior spinal fusion because it can provide prolonged analgesia after a single injection. Here, we present a case report of two such patients, and we compare outcomes with a retrospective cohort of 13 patients with AIS who received IV methadone instead of ESPB. ESPB patients seemed to have less opioid use and shorter length of stay but higher pain scores, although the sample size is too small for meaningful statistical analysis. Future prospective trials are needed to see if differences in outcomes truly exist.

Patient Characteristics, Injury Types, and Costs Associated with Secondary Over-Triage of Isolated Cervical Spine Fractures.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To aim of this study was to identify patient variables, injury characteristics, and costs associated with operative and non-operative treatment following inter-facility transfer of patients with isolated cervical spine fractures. SUMMARY OF BACKGROUND DATA: Patients with isolated cervical spine fractures are subject to inter-facility transfer for surgical assessment, yet are often treated nonoperatively. The American College of Surgeons' benchmark rate of "secondary over-triage" is <50%. Identifying patient and injury characteristics as well as costs associated with treatment following transfer of patients with isolated cervical spine fractures may help reduce rates of secondary over-triage and healthcare expenditures. METHODS: Patients transferred to a Level-1 trauma center with isolated cervical spine fractures between January 2015 and September 2020 were identified. Patient demographics, comorbidities, insurance data, injury characteristics, imaging workup, treatment, and financial data were collected for all patients. Multivariable logistic regression models were constructed to identify patient and injury characteristics associated with surgical treatment. RESULTS: Nearly 75% of patients were treated non-operatively. Over 97% of transfers were accepted by the general surgery trauma service. Multivariable modeling found that higher BMI, presence of any neurologic deficit including spinal cord or isolated spinal nerve root injuries, present smoking status, or cervical spine magnetic resonance imaging obtained post-transfer, were associated with surgical treatment for isolated cervical spine fractures. Among patients with type II dens fractures, increased fracture displacement was associated with surgical treatment. Median charges to patients treated operatively and nonoperatively were $380,890 and $90,734, respectively. Median hospital expenditures for patients treated operatively and nonoperatively were $55,115 and $12,131, respectively. CONCLUSION: A large proportion of patients with isolated cervical spine fractures are subject to over-triage. Injury characteristics are important for determining need for surgical treatment, and therefore interfacility transfer. Improving communication with spine surgeons when deciding to transfer patients may significantly reduce health care costs and resource use.Level of Evidence: 4.

High- versus low-dose tranexamic acid as part of a Patient Blood Management strategy for reducing blood loss in patients undergoing surgery for adolescent idiopathic scoliosis.

PURPOSE: The administration of tranexamic acid (TXA) has been shown to be beneficial in reducing blood loss during surgery for adolescent idiopathic scoliosis (AIS), but optimal dosing has yet to be defined. This retrospective study compared high- versus low-dose TXA as part of a Patient Blood Management strategy for reducing blood loss in patients undergoing posterior spine fusion surgery. METHODS: Clinical records were reviewed for 223 patients with AIS who underwent posterior spinal fusion of five or more levels during a 6-year time period. We compared normalized blood loss, total estimated blood loss (EBL), and the need for transfusion between patients receiving high-dose TXA (loading dose of ≥ 30 mg/kg) versus low-dose TXA (loading dose < 30 mg/kg). Both groups received maintenance TXA infusions of 10 mg/kg/h until skin closure. RESULTS: Patient demographics, curves, and surgical characteristics were similar in both groups. The high-dose TXA group had a 36% reduction in normalized blood loss (1.8 cc/kg/level fused versus 2.8 cc/kg/level fused, p < 0.001) and a 37.5% reduction in total EBL (1000 cc versus 1600 cc, p < 0.001). Patients in the high-dose group had a 48% reduction in PRBC transfusion, with only 19% receiving a transfusion of PRBC compared to 67% in the low-dose group (p < 0.001). CONCLUSION: When combined with other proven Patient Blood Management strategies, the use of high-dose TXA compared to low-dose TXA may be beneficial in reducing blood loss for patients with adolescent idiopathic scoliosis undergoing posterior spinal fusion surgery. LEVEL OF EVIDENCE: Level III, retrospective cohort.

Variability in Opioid Prescription Following Primary Single-Level Lumbar Microdiscectomy.

STUDY DESIGN: Retrospective case series. OBJECTIVES: To evaluate the variability in opioid prescription following primary single-level lumbar microdiscectomy. METHODS: We retrospectively reviewed consecutive patients who underwent primary single-level lumbar microdiscectomy. Only opioid-naïve patients ≥18 years old were included. Patients who had revision microdiscectomy, multilevel decompression, and/or any complication requiring prolonged hospital stay (>2 days) were excluded. The primary outcomes were the maximum daily dosage of opioids prescribed in morphine milligram equivalents (MME) and the number of pills prescribed (equivalent to 5 mg hydrocodone). RESULTS: Between 2014 and 2019, 169 patients (90 men, 79 women) met inclusion criteria, with a mean age of 46.9 years. Surgery resulted in a statistically significant improvement in VAS (Visual Analogue Scale) score (6.4 to 2.5, P < .01). At discharge, 8 patients (4.7%) did not receive any opioid prescription. Of the remaining 161 patients, 1 patient (0.01%) received hydromorphone, 30 (18.6%) Percocet, 43 (26.7%) oxycodone, and 87 Norco (54.0%). The length of opioid prescription was 6.7 days. The maximum daily dosage of opioids prescribed was 70.4 MME (SD 32.1). The total number of pills prescribed was 89.4 (SD 54.7). Twenty-five patients (15.5%) received a refill prescription. Multivariate analysis demonstrated the operating service, prescriber, and hospital admission were statistically significant predictors of maximum daily MME. The prescriber and hospital admission were statistically significant predictors of total number of pills prescribed. CONCLUSIONS: We found significant variability in opioid prescription following primary single-level lumbar microdiscectomy. For standard spinal procedures like lumbar microdiscectomy, opioid-prescribing guidelines should be established to standardize postoperative pain management.

Ligament Augmentation With Mersilene Tape Reduces the Rates of Proximal Junctional Kyphosis and Failure in Adult Spinal Deformity.

OBJECTIVE: To investigate prevention of proximal junctional kyphosis (PJK) and failure (PJF) following adult spinal deformity (ASD) surgery utilizing a novel technique of posterior ligament augmentation with polyester fiber tether. METHODS: This study evaluated ASD adult patients who underwent posterior decompression and instrumented fusion from the thoracolumbar junction (T9-L1) to the pelvis from 2011-2017. Basic demographic data were obtained. Radiographic outcomes included proximal junctional angle (PJA), sagittal vertical axis, PJK, and PJF. The study population was divided into patients who had ASD surgery with and without ligamentous augmentation. RESULTS: A total of 43 subjects were evaluated, including 20 without and 23 with ligamentous augmentation. PJA increased over time for both groups. PJA was smaller for the augmented group, and rate of increase in PJA was slower in the augmented group (p < 0.0001). The rate of PJK was significantly higher in the nonaugmented group (p = 0.01). PJF was significantly less common in the augmented group (p = 0.003). Time to revision surgery was lower in the nonaugmented group (p = 0.003). CONCLUSION: Our novel ligament augmentation technique utilizing polyethylene tape is an effective technique to slow progression of the PJA and lower the risk for proximal junctional disease in ASD surgery.