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We present a census of Lyα emission at , utilizing deep near-infrared Hubble Space Telescope grism spectroscopy from the first six completed clusters of the Grism Lens-Amplified Survey from Space (GLASS). In 24/159 photometrically selected galaxies we detect emission lines consistent with Lyα in the GLASS spectra. Based on the distribution of signal-to-noise ratios and on simulations, we expect the completeness and the purity of the sample to be 40%–100% and 60%–90%, respectively. For the objects without detected emission lines we show that the observed (not corrected for lensing magnification) 1σ flux limits reach 5 × 10−18 erg s−1 cm−2 per position angle over the full wavelength range of GLASS (0.8–1.7 μm). Based on the conditional probability of Lyα emission measured from the ground at , we would have expected 12–18 Lyα emitters. This is consistent with the number of detections, within the uncertainties, confirming the drop in Lyα emission with respect to . Deeper follow-up spectroscopy, here exemplified by Keck spectroscopy, is necessary to improve our estimates of completeness and purity and to confirm individual candidates as true Lyα emitters. These candidates include a promising source at z = 8.1. The spatial extent of Lyα in a deep stack of the most convincing Lyα emitters with is consistent with that of the rest-frame UV continuum. Extended Lyα emission, if present, has a surface brightness below our detection limit, consistent with the properties of lower-redshift comparison samples. From the stack we estimate upper limits on rest-frame UV emission line ratios and find and , in good agreement with other values published in the literature. [ABSTRACT FROM AUTHOR]

Recent James Webb Space Telescope (JWST) observations have revealed an unexpected abundance of massive-galaxy candidates in the early Universe, extending further in redshift and to lower luminosity than what had previously been found by submillimetre surveys 1-6 . These JWST candidates have been interpreted as challenging the Λ cold dark-matter cosmology (where Λ is the cosmological constant) 7-9 , but, so far, these studies have mostly relied on only rest-frame ultraviolet data and have lacked spectroscopic confirmation of their redshifts 10-16 . Here we report a systematic study of 36 massive dust-obscured galaxies with spectroscopic redshifts between 5 and 9 from the JWST FRESCO survey. We find no tension with the Λ cold dark-matter model in our sample. However, three ultra-massive galaxies (logM ★ /M ⊙  ≳ 11.0, where M ★ is the stellar mass and M ⊙ is the mass of the Sun) require an exceptional fraction of 50 per cent of baryons converted into stars-two to three times higher than the most efficient galaxies at later epochs. The contribution from an active galactic nucleus is unlikely because of their extended emission. Ultra-massive galaxies account for as much as 17 per cent of the total cosmic star-formation-rate density 17 at redshifts between about five and six., Competing Interests: Competing interests The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

In bis(trifluoromethylsulfonyl)amide (TFSA - )-based ionic liquid (IL), 1-ethyl-3-methylimidazolium TFSA - ([C 2 mIm][TFSA]), the complex formation equilibria of zinc(II) ion (Zn 2+ ) with ethylenediamine (EN) have been investigated. An EN molecule may coordinate with Zn 2+ as a bidentate ligand. First, the formation of Zn 2+ -EN complexes in [C 2 mIm][TFSA] was confirmed from the difference of 1 H and 13 C NMR chemical shift values of EN molecules between [C 2 mIm][TFSA]-EN binary solvents and the 0.1 mol dm -3 Zn(TFSA) 2 /[C 2 mIm][TFSA]-EN solutions as a function of EN mole fraction x EN . Second, the stability constants of Zn 2+ -EN complexes formed in the IL were determined from the concentration ratio [EN]/[Zn 2+ ] dependence of 15 N NMR chemical shift values of the TFSA - N atom in the Zn 2+ /IL-EN solutions. In the IL, mono-, bis-, and tris-EN complexes are successively formed by 1:1 replacement of TFSA - anions coordinated with Zn 2+ by EN molecules with increasing EN content. Third, 1 H and 13 C NMR measurements with the help of density functional theory (DFT) calculations were made on [C 2 mIm][TFSA]-EN binary solvents as a function of x EN to clarify key interactions to the mechanism of the complex formation. Fourth, the stability constants of Zn 2+ -EN complexes in the IL were compared with those in aqueous solutions. It was suggested that the hydrogen bonding of the EN molecule with the imidazolium ring H atoms and the TFSA - O atoms reduces the stability of the mono-EN complex in the IL. In contrast, the intracomplex hydrogen bonds between EN and TFSA - in the first coordination shell contribute to the higher stability of the bis-EN complex in the IL than that in aqueous solutions. The difference in the stability constants between the tris-EN complexes and hexaacetonitrile complexes, where acetonitrile (AN) molecules act as monodentate ligands, was interpreted in terms of the higher electron donicity of EN. Finally, to verify the present evaluation, the experimental 13 C NMR chemical shift values of EN molecules in the solutions were compared with the theoretical values calculated by DFT using the stability constants determined.

Background: This study aimed to demonstrate the feasibility of lag screw exchange for painful lateral soft tissue impingement in patients initially treated with cephalomedullary nailing (CMN) for an intertrochanteric hip fracture., Methods: Ten patients initially treated with CMN for unstable intertrochanteric fractures presenting with persistent pain and radiographic evidence of lag screw lateral migration were treated with exchange of original screw with shorter lag screw buried in the lateral cortex to prevent impingement. Patients were evaluated for resolution of pain and achievement of pre-fracture ambulatory status at 6 months post-operatively., Results: Average age was 71.5 years (range: 62-88). Average length of follow-up was 24.9 months. All patients were female, with an average Charlson Comorbidity Index of 1.0 (0-3) and average Body Mass Index of 22.2 (16.0-31.1). Five of ten patients (50.0%) were treated with a cortisone injection in the trochanteric bursa prior to screw exchange with temporary pain relief. Five (50.0%) patients presented with limited range of hip motion. Five (50.0%) had history of prior or current bisphosphonate use. Average lag screw prominence was noted to be 12.2mm (7.9-17.6mm) on radiographic evaluation. Screw exchange was performed at an average of 18.6 months (5.4-44.9 months) following the index procedure. Average operating time of the screw exchange procedure was 45.3 minutes (34-69 minutes) and blood loss was <50mL in all cases. Replacement lag screws were an average of 16.0mm (10-25mm) shorter than the initial screw. All patients achieved complete or significant resolution of lateral thigh pain, and nine (90%) returned to pre-fracture ambulatory status by eight weeks after screw exchange. All patients remained pain free at six months after screw exchange., Conclusion: Lag screw exchange is a efficacious method to address the mechanical irritation of laterally protruding lag screws following IT hip fracture, while also prophylaxing against subsequent femoral neck fractures. Level of Evidence: IV ., Competing Interests: Disclosures: The authors report no potential conflicts of interest related to this study., (Copyright © The Iowa Orthopaedic Journal 2024.)

To determine if radiographic evidence of posttraumatic osteoarthritis (PTOA) following tibial plateau fracture correlates with poorer clinical and functional outcomes, patients with tibial plateau fractures were followed at 3, 6, and 12 months. All patients had baseline radiographs and computed tomography scan. Radiographs obtained at each follow-up were reviewed for healing, articular incongruence, hardware positional changes, and the development of postinjury arthritic change. Cohorts were determined based on the presence (PTOA) or absence (NPTOA) of radiographic evidence of PTOA. Demographics, fracture classification, complications, additional procedures, and functional status were compared between cohorts. Sixty patients had radiographic evidence of PTOA on follow-up radiographs at a mean final follow-up of 24.2 months. The NPTOA cohort was composed of 210 patients who were matched to the PTOA cohort based on age and Charlson comorbidity index. Mean time to fracture union for the overall cohort was 4.86 months. Cohorts did not differ in Schatzker classification, time to healing, injury mechanism, or baseline Short Musculoskeletal Function Assessment (SMFA). Patients with PTOA had a greater degree of initial depression and postoperative step-off, higher incidence of initial external fixator usage, higher rates of reoperation for any reason, and higher rates of wound complications. Associated soft tissue injury and meniscal repair did not coincide with the development of PTOA. Range of motion and SMFA scores were significantly worse at all time points in patients with PTOA. Although fracture patterns are similar, patients who required an initial external fixator, had a greater degree of initial depression or residual articular incongruity, underwent more procedures, and developed an infection were found to have increased incidence of PTOA. Radiographic evidence of osteoarthritis correlated with worse functional status in patients. The goal of surgery should be restoration of articular congruity and stability to mitigate the risk of PTOA, although this alone may not prevent degenerative changes. Patients with early loss of range of motion should be aggressively treated as this may precede the development of PTOA., Competing Interests: S.R.K. is a consultant for Stryker. K.A.E. is a consultant for Exactech and Synthes, receives royalties from Exactech, Wolters Kluwer, and Slack Inc, receives research support from Synthes and Acumed, and is a paid lecturer for Smith and Nephew. This article contains data which may be incorporated into the PersonaCare software, which is owned in part by S.R.K. and K.A.E. Rest authors declare no conflict of interest., (Thieme. All rights reserved.)

Background: The purpose of this study was to compare outcomes following surgical treatment of tibial plateau fractures in an elderly (≥ 65y) and non-elderly (< 65) population., Methods: Patients with tibial plateau fractures were prospectively followed. Patients were included if they were operatively treated, had an Injury Severity Score of < 16, and had follow-up through 12 months. Clinical, radiographic, and functional outcomes were evaluated at the 3, 6, and 12-month follow-up points., Results: Mean time to radiographic fracture union was by 4.68 and 5.26 months in young and elderly patients, respectively (p = 0.25). There was no difference in self-reported baseline SMFA (p = 0.617). SMFA scores were better in younger patients at 3 months (p = 0.031), however this did not hold when multivariate modeling controlled for other factors. There was no difference at 6 and 12 months (p = 0.475, 0.392). There was no difference in range of knee motion at 3 months. At 6 and 12 months, young patients had statistically but not clinically better range of knee motion (p = 0.045, 0.007). There were no differences in overall reoperation rates, conversion arthroplasty, post-traumatic osteoarthritis or wound complications., Conclusions: Age greater than 65 does not appear to portend poorer outcomes after surgical repair of a tibial plateau fracture. The complication profiles are similar. Elderly and younger patients had similar function at 12 months compared to their baseline. These data suggest that age should not be a disqualifying factor when considering whether a patient with a tibial plateau fracture should be treated operatively., (© 2022. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Purpose: To determine if the DTS decreases radiation exposure (primary outcome measure), fluoroscopy time (secondary outcome measure), and time to distal screw placement (secondary outcome measure) compared to the freehand "perfect circles" method when used for locking of cephalomedullary nails in the treatment of femur fractures METHODS: Fifty-eight patients with hip or femoral shaft fractures that were treated with a long cephalomedullary nail were enrolled in this study. Cohorts were determined based on the method of distal interlocking screw placement into either the "Perfect Circles" or "Distal Targeting" cohort. Time from cephalad screw placement to placement of final distal interlocking screw (seconds), radiation exposure (mGy), and fluoroscopy time (seconds) were compared between groups. Hospital quality measures were compared between cohorts., Results: Use of the DTS resulted in 77% (4.3x) lower radiation exposure (p < 0.001), 64% (2.7x) lower fluoroscopy time (p < 0.001), and 60% (1.7x) lower intraoperative time from end of cephalad screw placement to end of distal interlocking screw placement (p < 0.001) compared to the freehand "perfect circles" method. There was no difference in 30-day or 90-day complication rates between cohorts., Conclusion: The Stryker Gamma3® Distal Targeting System is a safe, effective and efficient alternative to the freehand "perfect circles" method., Competing Interests: Declaration of interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

Introduction: The purpose of this study was to assess how quality and volume of common orthopaedic care varies across private, municipal, and federal healthcare delivery systems (HDSs)., Methods: Hip and knee arthroplasty, knee and shoulder arthroscopy, and hip fracture repair were audited over a two-year period. Electronic medical records were reviewed for demographics, diagnosis, lengths of stay (LoSs), surgical wait times, inpatient complication, readmission, and revision surgery rates. Multivariate regression controlled for differences in age, sex, diagnosis, and Charlson Comorbidity Index to determine how HDS correlated with surgical wait time, length of stay, complication rates, readmission, and revision surgery., Results: The 5,696 included patients comprise 87.4% private, 8.6% municipal, and 4.0% federal HDSs. Compared with private HDS for arthroplasty, federal surgical wait times were 18 days shorter (95% CI = 9 to 26 days, P < 0.001); federal LoS was 4 days longer (95% CI = 3.6 to 4.3 days, P < 0.001); municipal LoS was 1 day longer (95% CI = 0.8 to 1.4, P < 0.001); municipal 1-year revision surgery odds were increased (odds ratio [OR] = 2.8, 95% CI = 1.3 to 5.4, P = 0.045); and complication odds increased for municipal (OR = 12.2, 95% CI = 5.2 to 27.4, P < 0.001) and federal (OR = 12.0, 95% CI = 4.5 to 30.8, P < 0.001) HDSs. Compared with private HDS for arthroscopy, municipal wait times were 57 days longer (95% CI = 48 to 66 days, P < 0.001) and federal wait times were 34 days longer (95% CI = 21 to 47 days, P < 0.001). Compared with private HDS for fracture repair, municipal wait times were 0.6 days longer (95% CI = 0.2 to 1.0, P = 0.02); federal LoS was 7 days longer (95% CI = 3.6 to 9.4 days, P < 0.001); and municipal LoS was 4 days longer (95% CI = 2.4 to 4.8, P < 0.001). Only private HDS fracture repair patients received bone health consultations., Discussion: The private HDS provided care for a markedly larger volume of patients seeking orthopaedic care. In addition, private HDS patients experienced reduced surgical wait times, LoSs, and complication odds for inpatient elective cases, with better referral patterns for nonsurgical orthopaedic care after hip fractures within the private HDS. These results may guide improvements for federal and municipal HDSs., (Copyright © 2022 by the American Academy of Orthopaedic Surgeons.)

Objectives: This study compares demographics, outcomes, and costs of patients with similar multifragmentary pertrochanteric (MP) fracture patterns treated with either a short or long cephalomedullary nail (CMN) to determine treatment efficacy and value during hospital admission., Design: Retrospective cohort study., Setting: Level-1 trauma center., Patients: 384 patients who presented with a MP fracture [AO/OTA 31A2.2 and 31A2.3] at 1 of 3 hospitals within a single academic medical center., Intervention: Surgical treatment with either short or long CMN Main outcome measurements: Operative time, in-hospital complications, discharge disposition, procedural and total costs of admission., Results: Sixty-nine (18.0%) patients were treated with long CMNs compared to 315 patients treated with short CMNs. Patients treated with long CMNs had increased rates of transfusions of allogenic packed red blood cells (52.2% vs 34.0%, p = 0.005), discharge to rehabilitation facilities (91.3% vs 80.3%, p = 0.030), and had costlier hospital stays ($28,632.50 vs $23,024.86, p = 0.014) with longer (74.9 vs 52.3 min, p <0.001), costlier procedures and implants ($12,090.31 vs $9,647.41, p = 0.014) compared to patients treated with short CMNs. There were no differences in timing of radiographic healing, rates of readmission, nonunion, screw cut out, fixation failure, or peri‑implant fracture., Conclusions: Short and long CMNs are equally suitable implants for the most unstable intertrochanteric fracture patterns. Short CMNs correlate with reduced operative time and costs with non-inferior in-hospital complication rates, hospital quality measures, and less frequent rehabilitation facility discharges. Given the similar long-term outcomes demonstrated here and in the literature, this data suggests nail length selection should be driven more by cost and discharge considerations for MP fractures., Level of Evidence: level III., Competing Interests: Declaration of Competing Interest None., (Copyright © 2022. Published by Elsevier Ltd.)

Background: The purpose of this study is to determine if treated psychological depression is associated with poorer functional outcomes in patients who sustain tibial plateau fractures., Methods: Patients with a tibia plateau fracture were prospectively followed. Functional status was assessed using the Short Musculoskeletal Function Assessment (SMFA) at baseline (pre-injury), 3 months, 6 months, and 1 year post injury. Clinical outcomes were recorded at each follow up visit and radiographic outcomes were obtained from follow up radiographs. Records were reviewed to identify patients who were being treated for major depressive disorder (MDD). SMFA scores and clinical outcomes were compared between the depression and no depression cohorts., Results: 420 patients were treated for a tibial plateau fracture and the mean age was 50.83 ± 15.60 years. Forty-two (10%) patients with 42 fractures were being treated for MDD at the time of their fracture. Patients with MDD were older (p = 0.05) and were more likely female (p < 0.01). At baseline, the clinical depression cohort had worse Total SMFA scores compared to the non-depressed cohort (5.90 ± 14.41 vs. 2.69 ± 8.35, p < 0.01). There were no differences in total SMFA score or any SMFA subscores at 3, 6, and 12 months. The incidence of wound complications, reoperations, and radiographic outcomes also did not differ between the cohorts., Conclusion: Despite patients with MDD reporting higher SMFA (poorer) scores at baseline, MDD was not associated with worse injuries, diminished clinical or poorer functional outcomes following tibial plateau fractures., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Patients with metastatic spinal tumors often experience paralysis caused by spinal cord compression. Several studies have investigated metastatic lesion-related spinal cord compression. This study is the first to examine the relationship between the epidural spinal cord compression (ESCC) scale, which measures circumferential compression, and the functional outcomes of treatment, which were assessed at regular intervals after treatment until death. A total of 191 patients who had grade D or worse paralysis on the American Spinal Injury Association (ASIA) classification scale and a grade 1b or more severe cord compression on the ESCC scale were included in the study. Patients had been treated with surgery combined with radiotherapy (n=146) or radiotherapy alone (n=45). Three spinal surgeons assessed the ESCC grade of for patient, and the grade agreed to by at least 2 surgeons was adopted. After 4 weeks, re-evaluations were conducted by the same examiners. The authors also calculated the mean kappa coefficients for inter- and intra-examiner variability (0.88 and 0.93, respectively). The distribution of the ASIA grade differed significantly among the ESCC scale grades (P=.0102). However, the degree of improvement in paralysis in terms of the ASIA grade (≥1 grade of improvement, no change, or ≥1 grade of aggravation) was not significantly associated with the ESCC grade (P=.2334). The ESCC scale was found to be a useful indicator of circumferential spinal cord compression but was not identified as a significant functional prognostic factor for paralysis. [Orthopedics. 2020;43(6):e567-e573.]., (Copyright 2020, SLACK Incorporated.)

Background: Therapeutic intervention has recently been actively performed for metastatic spine tumor even though spinal cord paralysis is not clearly observed, but there has been no report in which the degree of spinal cord compression by tumor was taken into consideration for the paralysis-preventing effect of treatment. Thus, we investigated the neurological outcome after treatment of patients with spinal cord compression in a state of impending paralysis., Methods: A retrospective cohort study. The subjects were 88 patients with epidural spinal cord compression (ESCC) scale 1b or severer compression with American Spinal Injury Association (ASIA) E spinal metastasis. The neurological outcome after the therapeutic intervention was investigated at regular intervals until death. The therapeutic intervention was posterior decompression and stabilization in 18 patients, stabilization without posterior decompression in 15, and radiotherapy in 55 patients (3 groups)., Results: The ASIA aggravation group was comprised of 15 patients, and the severity of paralysis was ASIA A in 3, B in 3, C in 6, and D in 3. Paralysis appeared in 16.7% in the posterior decompression and stabilization group, 13.3% in the posterior stabilization without decompression group, and 18.8% in the radiotherapy group. In the transverse view, the incidence was high in cases with advancement to the intervertebral foramen and circumferential-type advancement, and paralysis developed in more than 20% of ESCC 1c or severer cases. Factors influencing neurological aggravation were investigated, but there was no significant factor., Conclusion: In ESCC 1b or severer cases with ASIA E spinal metastasis, paralysis aggravated after therapeutic intervention in 16.7% in the posterior decompression and stabilization group, 13.3% in the stabilization without decompression group, and 16.7% in the radiotherapy group. There was no significant factor influencing the development of paralysis.

Background: There have been only a few reports of subsequent postoperative vertebral fracture following posterior spinal instrumentation fusion, especially in elderly female patients. This study attempted to evaluate the long-term prevalence of subsequent postoperative vertebral fracture in female patients aged 70 years and older who underwent spine decompression and fusion surgery with pedicle screw fixation., Methods: We retrospectively reviewed prospectively collected data from 125 patients who met our inclusion and exclusion criteria. Patients were divided into 2 groups according to age: patients aged 70 years and older (Group A) and patients aged under 70 years of age (Group B). We evaluated incidence of subsequent postoperative vertebral fractures, type and timing of vertebral fractures, preoperative bone mineral density (BMD), preoperative diagnosis, surgical procedure, number of levels fused, extension of fusion to the lumbosacral junction, and presence of a transverse fixator., Results: Baseline characteristics excluding patients' age were not statistically different between the two groups. Preoperative BMD of Group A was an average 81.7% of the young adult mean (YAM) value and that of Group B was an average 85.1% YAM value. Subsequent postoperative vertebral fractures occurred in 22 (41.5%) of 53 in Group A. On the other hand, fracture occurred in 17 (23.6%) of 72 in Group B. There were significant differences between the groups (p = 0.02). The odds ratio for subsequent vertebral fracture was 2.4 (95% confidence interval: 1.1-5.2) in favor of Group A. Survival analysis showed that the rate of subsequent vertebral fracture was significantly higher in Group A (log-rank test, P = 0.007)., Conclusions: The incidence of subsequent vertebral fracture in patients aged 70 years and older was significantly higher than in patients aged under 70 years of age. In the case of pedicle screw fixation in elderly female patients, it is necessary to note the high risk of subsequent vertebral fracture despite short or non-rigid fusion. Vertebral fracture after posterior fusion surgery even for degenerative lumbar pathology could occur in more than one-third of female patients aged 70 years and older.

Spontaneous spinal epidural hematoma (SSEH) very rarely develops in infants younger than 1 year old. To our knowledge, no previous case of delayed-onset paralysis induced by SSEH communicated with hematoma in the paraspinal muscle has been reported in the literature. The authors present the case of a 6-month-old girl with a tumor mass on her back who developed a paresis of her bilateral lower limbs. On spinal magnetic resonance imaging, the epidural mass appeared to be a dumbbell type and communicated with the mass in the paraspinal muscle through T12/L1 intervertebral foramen at the right side. After excision of the mass in the paraspinal muscle, hemi-laminectomy of T10-L3 was performed. No solid lesion was also present in the spinal canal and it was found to be an epidural hematoma. No malignancy was observed on pathological examination, and vascular and nerve system tumors were negative. When a tumor mass suddenly develops on the back of an infant and motor impairment of the lower limbs develops as the mass gradually enlarges, differential diagnosis should be performed taking SSEH into consideration.

Purpose: Minimally invasive spine stabilization (MISt) using percutaneous pedicle screws plays a significant role in palliative surgery for metastatic spinal tumors. However, few studies have investigated surgical outcomes based on the epidural spinal cord compression scale (ESCCS). The purpose of this study was to examine outcomes of metastatic spinal tumors as evaluated by ESCCS in patients treated by MISt., Methods: The subjects were 56 patients who underwent MISt for metastatic spinal tumors, including 34 patients with ESCCS 2 or milder (group A) and 22 patients with ESCCS 3 (group B). We analyzed baseline characteristics, perioperative factors and clinical results such as postoperative survival time, neurological outcomes, Barthel Index for activities of daily living (ADL), visual analogue scale (VAS), and the rate of discharge to home., Results: The baseline age (P=0.07), tumor diagnosis (P=0.23), spinal level of compression (P=0.35), American Spinal Injury Association classification (P=0.49), revised Tokuhashi score (P=0.92), spinal instability neoplastic score (P=0.28), VAS (P=0.35), Barthel Index (P=0.07), American Society of Anesthesiologists physical status classification (P=0.76), and type of surgery (P=0.40) did not differ significantly between the two groups. The median postoperative survival time did not differ significantly between the groups (12.0 versus 15.0 months, P=0.60). Neurological improvement by at least 1 grade or maintenance of grade E was favorable in group A. Patients in group A had less posterior decompression (P=0.006), a higher rate of chemotherapy (P=0.009), a higher postoperative Barthel Index (P=0.04), and a higher rate of discharge to home (P=0.01) and no patients died in the hospital (P=0.004)., Conclusions: No significant difference was noted in the postoperative survival time between the 2 groups. Patients in the ESCCS 2 or milder group had favorable neurological improvement, higher rates of chemotherapy, better postoperative ADL, and the higher rate of discharge to home.

Metastases to the skull or upper cervical spine from hepatocellular carcinoma (HCC) are very rare. We herein report a unique case of two-site surgery for both skull and upper cervical spine metastases from HCC. The patient was a 64-year-old man with cervical pain. Computed tomography (CT) revealed osteolytic change related to metastatic cervical spine and occipital bone tumors. Two-stage surgery involving posterior occipitocervical fusion and occipital bone tumor resection was performed. The patient's pain decreased in severity, and postoperative radiotherapy and chemotherapy could be conducted. The postoperative course was favorable, and the patient exhibited improvement in his activities of daily living. Neither cervical spine X-ray examination nor CT showed any instrumentation failure, such as screw loosening, before the patient died of liver failure 13 months after surgery. Patients with both skull and upper cervical spine metastases from liver cancer may have a markedly unfavorable prognosis. Even in these patients, however, surgery as an aggressive palliative treatment may prolong the survival period or maintain the quality of life as long as the patient's general condition permits.

Change history: In this Letter, author M. Akhlaghi should be associated with affiliation (2) rather than (3). This error has been corrected online.

Background: The Magerl and Goel-Harms techniques have been reported to produce excellent treatment outcomes in cases of atlantoaxial subluxation, but they also carry a risk of vertebral artery injuries. In order to completely prevent such injuries, we developed a surgical procedure, involving bone grafting between the C1 posterior arch and C2 lamina with clamp- or hook-and-rod-based fixation combined with the insertion of an interference screw into the posterior atlantoaxial joint., Methods: This was a retrospective single-center study. The subjects were 58 patients in whom atlantoaxial subluxation was treated with the abovementioned procedure after 1995 (33 patients with rheumatoid arthritis (RA group) and 25 patients without rheumatoid arthritis (non-RA group)). The clinical outcomes and imaging findings of anterior subluxation at ≥ 2 years after surgery were compared between the RA and non-RA groups., Results: No vertebral artery injuries occurred during surgery. Seven and two patients died during the follow-up period in the RA and non-RA groups, respectively, but none of these deaths were associated with surgery. At ≥ 2 years after surgery, the visual analogue scale score, Japanese Orthopaedic Association score, and Ranawat classification had significantly improved in both groups (p < 0.001). Radiologically, bone fusion was noted in all patients. Significant changes in the atlas-dens interval (ADI) were seen immediately after surgery in both groups (p < 0.001). In the non-RA group, significant changes in the corrected atlantoaxial height were observed immediately after surgery (p < 0.01), and loss of correction was seen at the final follow-up, but it was not significant (p = 0.1965). No significant changes were noted in any other parameter. Regarding the postoperative alignment of the cervical spine, lordosis tended to decrease, but additional surgery was only performed in one patient, who had developmental stenosis at the mid-lower level and belonged to the RA group. No reoperations due to fused adjacent segmental disease or exacerbated curvature were required., Conclusion: In the present study, no vertebral artery injuries occurred during surgery, and no major perioperative complications developed. Favorable clinical outcomes were observed at ≥ 2 postoperative years although the patients' diseases varied. This procedure produced superior outcomes, especially in terms of spinal correction and the maintenance of the ADI.

Background: Proximal junctional kyphosis (PJK) following adult spinal deformity (ASD) surgery in elderly patients is markedly influenced by osteoporosis causing additional vertebral fracture and loosening of pedicle screws (PS). This study aimed to investigate the association between mean bone density represented in Hounsfield units (HU) on spinal computed tomography (CT) and revision surgery for PJK or postoperative additional vertebral fracture following ASD surgery in elderly patients., Methods: The subjects were 54 ASD patients aged 65 years or older who were treated with correction and fusion surgery of four or more levels and could be followed for 2 years or longer. Bone density was measured before surgery using lumbar dual-energy X-ray absorptiometry (DXA) and spinal CT in all patients. The patients were divided into group A (n = 14) in which revision surgery was required for PJK or additional vertebral fracture and group B (n = 40) in which revision surgery was not required. We retrospectively investigated incidences of PJK, additional vertebral fracture, and PS loosening, perioperative parameters, radiographic parameters before and after surgery, and osteoporosis treatment administration rate., Results: No significant difference was noted in young adult mean (YAM) on DXA between groups A and B, respectively (P = 0.62), but the mean bone densities represented in HU of the T8 (P = 0.002) and T9 (P = 0.01) vertebral bodies on spinal CT were significantly lower in group A, whereas those of the L4 (P = 0.002) and L5 (P = 0.01) vertebral bodies were significantly higher in group A. The incidence of PJK was not significantly different (P = 0.07), but the incidence of additional vertebral fracture was significantly higher in group A (P < 0.001). The incidences of uppermost PS loosening within 3 months after surgery were 71% and 40% in groups A and B, respectively (P = 0.04)., Conclusions: In elderly patients who required revision surgery, the mean bone densities of vertebral bodies at T8 and T9 were significantly lower. The mean bone density represented in HU on spinal CT may be useful for risk assessment of and countermeasures against revision surgery after ASD surgery in elderly patients.

Galaxies are surrounded by large reservoirs of gas, mostly hydrogen, that are fed by inflows from the intergalactic medium and by outflows from galactic winds. Absorption-line measurements along the lines of sight to bright and rare background quasars indicate that this circumgalactic medium extends far beyond the starlight seen in galaxies, but very little is known about its spatial distribution. The Lyman-α transition of atomic hydrogen at a wavelength of 121.6 nanometres is an important tracer of warm (about 10 4 kelvin) gas in and around galaxies, especially at cosmological redshifts greater than about 1.6 at which the spectral line becomes observable from the ground. Tracing cosmic hydrogen through its Lyman-α emission has been a long-standing goal of observational astrophysics 1-3 , but the extremely low surface brightness of the spatially extended emission is a formidable obstacle. A new window into circumgalactic environments was recently opened by the discovery of ubiquitous extended Lyman-α emission from hydrogen around high-redshift galaxies 4,5 . Such measurements were previously limited to especially favourable systems 6-8 or to the use of massive statistical averaging 9,10 because of the faintness of this emission. Here we report observations of low-surface-brightness Lyman-α emission surrounding faint galaxies at redshifts between 3 and 6. We find that the projected sky coverage approaches 100 per cent. The corresponding rate of incidence (the mean number of Lyman-α emitters penetrated by any arbitrary line of sight) is well above unity and similar to the incidence rate of high-column-density absorbers frequently detected in the spectra of distant quasars 11-14 . This similarity suggests that most circumgalactic atomic hydrogen at these redshifts has now been detected in emission.

Background: The prognosis of hepatocellular carcinoma (HCC) used to be poor, but it has recently improved, which has meant that clinicians have greater opportunity to treat spinal metastases and the associated epidural spinal cord compression. However, there have been few systematic functional studies about HCC-derived spinal metastases. The treatment outcomes of surgical treatment for HCC-derived metastatic spinal tumors were investigated., Methods: The post-treatment survival period and pain, paralysis, and disturbance of activities of daily living (ADL) were investigated in 60 patients (surgery 25, conservative treatment 35)., Results: The mean post-treatment survival period was 7.4 ± 8.2 months (range 0.3-36 months). Univariate analysis indicated that the following factors influenced survival: the patient's general condition, presence/absence of major internal organ metastasis, serum albumin level, Child-Pugh classification, surgical treatment for spinal metastasis, and bone-modifying agent treatment. In the multivariate analysis of these 6 items, 3 significant factors were extracted: the patient's general condition, the serum albumin level, and bone-modifying agent treatment. Pain significantly improved in both groups (p < 0.001). Paralysis did not change significantly in the surgical group (p = 0.575), but it was significantly aggravated in the conservative treatment group (p = 0.047). The ADL abilities of the surgical group improved significantly (p < 0.001)., Conclusion: Most patients exhibited poor survival. In the conservative treatment group, paralysis was significantly aggravated, and little improvement was seen in the patients' ADL abilities. In the surgical group, the patients' ADL abilities improved significantly, but their paralysis did not. Therefore, surgery should be actively performed for HCC-derived spinal metastasis whenever it is indicated.

OBJECTIVE The range of decompression in posterior decompression and fixation for ossification of the posterior longitudinal ligament in the thoracic spine (T-OPLL) can be established using an index of spinal cord decompression based on the ossification-kyphosis angle (OKA) measured in the sagittal view on MRI. However, an appropriate OKA cannot be achieved in some cases, and posterior fixation is applied in cases with insufficient decompression. Moreover, it is unclear whether spinal cord decompression of the ventral side is essential for the treatment of OPLL. In this retrospective analysis, the efficacy of posterior decompression and fixation performed for T-OPLL was investigated after the range of posterior decompression had been set using the OKA. METHODS The MRI-based OKA is the angle from the superior margin at the cranial vertebral body of the decompression site and from the lower posterior margin at the caudal vertebral body of the decompression site to the prominence of the maximum OPLL. Posterior decompression and fixation were performed in 20 patients. The decompression range was set so that the OKA was ≤ 23° or the minimum if this value could not be achieved. Cases in which an OKA ≤ 23° could and could not be achieved were designated as groups U (13 patients) and O (7 patients), respectively. The mean patient ages were 50.5 and 62.1 years (p = 0.03) and the mean preoperative Japanese Orthopaedic Association (JOA) scores were 5.9 and 6.0 (p = 0.9) in groups U and O, respectively. The postoperative JOA score, rate of improvement of the JOA score, number of levels fused, number of decompression levels, presence of an echo-free space during surgery, operative time, intraoperative blood loss, and perioperative complications were examined. RESULTS In groups U and O, the mean rates of improvement in the JOA score were 50.0% and 45.6% (p = 0.3), the numbers of levels fused were 6.7 and 6.4 (p = 0.8), the numbers of decompression levels were 5.9 and 7.4 (p = 0.3), an echo-free space was noted during surgery in 92.3% and 42.9% of cases (p = 0.03), the operative times were 292 and 238 minutes (p = 0.3), and the intraoperative blood losses were 422 and 649 ml (p = 0.7), and transient aggravation of paralysis occurred as a perioperative complication in 2 and 1 patient, respectively. CONCLUSIONS There was no significant difference with regard to the recovery rate of the JOA score between patients with (group U) and without (group O) sufficient spinal cord decompression. The first-line surgical procedure of posterior decompression and fixation with the range of posterior decompression set as an OKA ≤ 23° before surgery involves less risk of postoperative aggravation of paralysis and may result in a better outcome.

Surgical treatment of multiple vertebral fractures in patients with glucocorticoid-induced osteoporosis is difficult because of a high rate of secondary fracture postoperatively. A case is described in which initial treatment with teriparatide to improve osteoporosis followed by treatment of kyphosis with correction fusion achieved a favorable outcome., Introduction: Secondary fracture frequently occurs after treatment of vertebral fracture with vertebroplasty and balloon kyphoplasty in patients with glucocorticoid-induced osteoporosis, but effective treatment of multiple vertebral fractures has rarely been reported. Thus, a treatment of kyphosis following multiple vertebral fractures associated with glucocorticoid-induced osteoporosis is required., Methods: The patient was a 24-year-old woman diagnosed with glucocorticoid-induced osteoporosis who was under treatment with oral alendronate, vitamin D, and elcatonin injection. Secondary multiple vertebral fractures occurred despite these treatments and low back pain gradually aggravated., Results: Vertebroplasty or balloon kyphoplasty was not performed in the early phase. Instead, treatment with teriparatide was used for initial improvement of osteoporosis. Kyphosis in the center of the residual thoracolumbar junction was then treated with posterior correction fusion. At 2 years after surgery, the corrected position has been maintained and no new fracture has occurred., Conclusion: There is no established method for treatment of multiple vertebral fractures caused by glucocorticoid-induced osteoporosis. Initial treatment with teriparatide to improve osteoporosis followed by treatment of kyphosis with correction fusion may result in a more favorable outcome.

Background: Posterior decompression and stabilization plays significant roles in palliative surgery for metastatic spinal tumor. However, the indication for addition of posterior decompression have not been examined. The purpose of this study was to investigate a retrospective cohort of outcomes of metastatic spinal tumor treated with minimally invasive spine stabilization (MISt) with or without posterior decompression., Methods: The subjects were 40 patients who underwent MISt using percutaneous pedicle screws for metastatic spinal tumor, including 20 patients treated with stabilization alone (group A) and 20 patients with added posterior decompression (group B). We analyzed baseline characteristics, postoperative survival time, and perioperative factors such as neurological outcomes, Barthel Index, VAS, and rate of discharge to home., Results: The mean ages were 70 and 66 years old (P = 0.06), the mean revised Tokuhashi scores were 7.2 and 5.8 (P = 0.1), the mean spinal instability neoplastic scores (SINS) were 10.5 and 9.0 (P = 0.04), and the mean Barthel Index for ADL were 65.5 and 41.0 (P = 0.06) in groups A and B, respectively. The median postoperative survival time did not differ significantly between groups A and B (12.0 vs. 6.0 months, P = 0.09). Patients in group A had a significantly shorter operation time (166 vs. 232 min, P = 0.004) and lower intraoperative blood loss (120 vs. 478 mL, P < 0.001). Postoperative paralysis (P = 0.1), paralysis improvement rate (P = 0.09), postoperative Barthel Index (P = 0.06), and postoperative VAS (P = 0.6) did not differ significantly between the groups. The modified Frankel classification improved from D1 or D2 before surgery to D3 or E after surgery in 4 of 10 cases (40%) in group A and 8 of 8 patients (100%) in group B (P = 0.01). Significantly more patients were discharged to home in group A (P = 0.02), whereas significantly more patients died in the hospital in group B (P = 0.02)., Conclusions: Patients treated without decompression had a shorter operation time, less blood loss, a higher rate of discharge to home, and lower in-hospital mortality, indicating a procedure with lower invasiveness. MISt without decompression is advantageous for patients with D3 or milder paralysis, but decompression is necessary for patients with D2 or severer paralysis.

Study Design: A retrospective, single-institute, and radiographic study., Objective: To evaluate the relationship between the epidural spinal cord compression (ESCC) scale and the severity of metastatic spine tumor-induced paralysis., Summary of Background Data: The ESCC scale is used to evaluate the grade of spinal cord compression on T2-weighted magnetic resonance imaging (MRI). However, few studies have investigated the relationship between such MRI findings and paralysis., Methods: The subjects were 467 patients with metastatic spine tumors and grade 1b or worse spinal cord compression according to the ESCC scale. Evaluations using this scale were performed by three spine surgeons, and results that were obtained by two or more surgeons were adopted. We also examined patients whose spinal cord compression deteriorated by one grade or more to American Spinal Injury Association (ASIA) grade C or worse within the first 3 weeks after MRI., Results: The kappa coefficients for inter- and intraexaminer variability were 0.90 and 0.95, respectively. ASIA grade D or worse paralysis developed in at least 50% of the patients with ESCC grade 1b or worse spinal cord compression at the C1-T2 and at least 50% of those with ESCC grade 1c or worse spinal cord compression at the T3-L5. The frequency of ASIA grade C or worse paralysis was high among the patients with ESCC grade 2 or worse spinal cord compression at the C7-L1. Nineteen patients experienced rapid deterioration of one grade or more to ASIA grade C or worse paralysis within the first 3 weeks after MRI. Of these, paralysis occurred in at least 30% of the patients with anterolateral or circumferential cord compression combined with ESCC grade 2 or 3 compression at the C7-L1., Conclusion: The severity of paralysis was not correlated with the ESCC scale. Patients with anterolateral or circumferential ESCC grade 2 or 3 cord compression at the C7-L1 are at high risk of rapidly progressive paralysis., Level of Evidence: 4.

Background: Surgeries performed for metastatic spinal tumor are mostly palliative and are controversial for patients with short life expectancy. We investigated whether palliative posterior spinal stabilization surgery with postoperative multidisciplinary therapy results in improvement of life prognosis and activities of daily living (ADL) in patients with metastatic spinal tumor., Methods: The subjects were 55 patients who underwent palliative posterior-only instrumentation surgery for metastatic spinal tumor at our hospital between 2012 and 2015. Postoperative survival, early paralysis improvement, ADL improvement, and rate of discharge to home were examined., Results: The patients included 37 males and 18 females, and the mean age at the time of surgery was 66.8 years old. The mean Tokuhashi score was 7.1, the mean spinal instability neoplastic score (SINS) was 9.4, and the epidural spinal cord compression scale (ESCCS) was grade 3 in 20 patients (36.3%). The mean Barthel index for ADL was 48.7. The median postoperative survival time determined using the Kaplan-Meier method was 12.0 months (95% confidence interval 2.4-21.5). Regarding improvement of paralysis, the modified Frankel scale was improved by one grade or more or grade E was maintained in 35 patients (63.6%), whereas paralysis aggravated in 2 (3.6%). In surgery, conventional posterior decompression and fixation were applied in 31 patients (56.3%), and minimally invasive spine stabilization was applied in 24 (43.6%). Postoperative chemotherapy was performed in 31 patients (56.3%), radiotherapy was used in 38 (69.0%), and a bone-modifying agent was administered in 39 (70.2%). Regarding ADL, the mean Barthel index improved from 48.5 before surgery to 74.5 after surgery. Thirty-seven patients (67.2%) were discharged to home., Conclusions: ADL improved and allowed discharge to home, and postoperative adjuvant therapy could be administered at a high rate in patients who received palliative posterior spinal stabilization surgery. Survival time extended beyond the preoperative life expectancy in many patients. Patients with a metastatic spinal tumor have short life expectancy and paralysis caused by spinal instability and spinal cord compression. However, multidisciplinary therapy including palliative posterior spinal stabilization surgery with reduced invasiveness and postoperative adjuvant therapy are effective in these patients.

Study Design: A retrospective, single-center study., Objective: Investigation of the changes in the treatment outcomes of patients with lung cancer derived metastatic spine tumors., Summary of Background Data: Metastatic spine tumors derived from lung cancer had been progressive, and their prognosis is poor. It has recently been reported that the use of molecularly targeted drugs and bone-modifying agents (BMAs) improved the treatment outcomes of patients with lung cancer, but no detailed information about the treatment of metastatic spine tumors has been reported., Methods: Two hundred seven patients with lung cancer derived metastatic spine tumors who were examined after 2000 were analyzed. They were divided into 54 patients who were treated in or before 2005 (surgical treatment: 25 patients, conservative treatment: 29 patients) (group B) and 153 patients who were treated from 2006 onwards, when a molecularly targeted drug and BMA were introduced (surgical treatment: 24, conservative treatment: 129) (group A), and the treatment outcomes of the two groups were compared., Results: Significant differences in age and the affected vertebral level, paralysis grade, and Tokuhashi score (general condition, the number of vertebral metastases, and the total score) were detected between the groups. Regarding treatment outcomes, the mean duration of the post-treatment survival period was 5.1 and 9.3 months in groups B and A, respectively, that is, it was significantly longer in group A (P < 0.05). No significant intergroup difference in pain improvement was noted, and no significant post-treatment improvement in paralysis was achieved in either group. The post-treatment discharge-to-home eligibility rate did not differ significantly between the groups, but the Barthel Index improved significantly after treatment in group A (P < 0.05)., Conclusion: After molecularly targeted drugs and BMA were introduced as treatments for lung cancer derived metastatic spine tumors, the survival periods of patients with such tumors increased, and their activity of daily living after treatment improved., Level of Evidence: 4.

The goal of the study was to evaluate minimally invasive palliative surgery and the effect of postoperative adjuvant therapy for metastatic spinal tumor with a limited vital prognosis. Of the 70 patients who underwent palliative surgery for metastatic spinal tumor at the authors' hospital between March 2012 and May 2016, thirty-three were treated with minimally invasive spine stabilization (MISt) using percutaneous pedicle screws (PPSs) and included in the current study. Of the 33 patients, 26 were men and 7 were women; mean age at surgery was 68.6 years. Intraoperatively, posterior decompression and fusion was performed in 17 (51.5%) patients and fusion only was performed in 16 (48.5%). Mean operative time was 202.5 minutes, mean intraoperative blood loss was 331.6 mL, and intraoperative blood loss was 1500 mL or greater in 2 (6.1%) patients. Median postoperative survival time determined using the Kaplan-Meier method was 11.0 months (95% confidence interval, 7.3-14.6). Regarding improvement of paralysis, neurological deficit was improved by at least 1 Frankel grade for 15 (45.5%) patients, and the number of ambulatory patients increased from 22 (66.7%) to 25 (75.8%). Postoperative adjuvant therapy included chemotherapy in 17 (51.5%) patients, radiotherapy in 21 (63.6%), and bone-modifying agent treatment in 25 (75.8%). The mean Barthel Index for activities of daily living improved from 53.5 preoperatively to 71.5 postoperatively. Discharge to home was possible for 23 (69.7%) patients. Activities of daily living for patients with metastatic spinal tumor were improved by minimally invasive palliative surgery with MISt using PPSs and postoperative adjuvant therapy. [Orthopedics. 2017; 40(4):e693-e698.]., (Copyright 2017, SLACK Incorporated.)

A 63-year-old man revealed a four-month history of muscle weakness of the lower limbs, hypoesthesia of the L5 and S1 area and ischuria. On MRI, the spinal cord was compressed by an encircled mass, which showed hypointensity on T1- and T2-weighted images with gadolinium enhancement at the Th11 to Th12 vertebra. Because of the rapid progression of myelopathy, posterior decompression was performed and idiopathic hypertrophic spinal pachymeningitis (HSP) was finally diagnosed. The patient's neurological signs markedly improved with postoperative corticosteroid treatment. Idiopathic HSP is a clinical emergency and early surgical intervention is essential to prevent irreversible damage to the nervous system.

Nucleopeptides Ac-Tyr(p3' dACGT)-Ala-Phe-Gly-NH2, Ac-Thr(p3'dACGT)-Ala-Phe-Gly-OH, Ac-Ser(p3'dACGT)-Ala-Phe-Gly-OH, and Phac-Hse(p3'dACGT)-Ala-Phe-Gly-OH, in which the 3'-end of a tetradeoxyribonucleotide is linked by a phosphodiester bond to a hydroxylated amino acid, were synthesized using a stepwise solid-phase methodology to study the influence of the linking amino acid on their stability to 3'-exonucleases. HPLC analysis of the reaction crudes after treatment of each nucleopeptide with snake venom phosphodiesterase showed that the lability of the amino acid-nucleoside linkage increases in the order Thr < Ser < Hse < Tyr.