When evaluating MRIs for glioblastoma progression, previous scans are usually included into the review. Nowadays dynamic susceptibility contrast (DSC)-perfusion is an essential component in MR-diagnostics of gliomas, since the extent of hyperperfusion upon first diagnosis correlates with gene expression and survival. We aimed to investigate if this initial perfusion signature also characterizes the glioblastoma at time of progression. If so, DSC-perfusion data from the initial diagnosis could be of diagnostic benefit in follow-up assessments.max) by standardized re-evaluation of the data including leakage correction. In addition, the corresponding tissue samples from 24 patients were examined histologically for the maximum vessel density within the tumor. Differences (paired t-test/ Wilcoxon matched pairs test) and correlations (Spearman) between the measurements at both timepoints were calculated.We retrospectively identified 65 patients with isocitrate dehydrogenase wildtype glioblastoma who had received technically identical DSC-perfusion measurements at initial diagnosis and at time of first progression. We determined maximum relative cerebral blood volume values (rCBVmax was consistently lower at time of progression compared to rCBVmax at time of first diagnosis (p < .001). There was no correlation between the rCBVmax values at both timepoints (r = .12). These findings were reflected in the histological examination, with a lower vessel density in progressive glioblastoma (p = .01) and no correlation between the two timepoints (r = -.07).The rCBVmax at initial diagnosis should be disregarded when reviewing MRIs for glioblastoma progression.Our results suggest that the extent of hyperperfusion in glioblastoma at first diagnosis is not a sustaining tumor characteristic. Hence, the rCBV To thisormation –8, the mormation . In glioormation . The rCBormation –13. Valuormation . Nonetheormation , yet assse (IDH) –18. Sevese (IDH) –18. The se (IDH) –21. Besise (IDH) –25. Despse (IDH) ,27. To oTherefore, the aim of this study was to investigate whether DSC-perfusion derived rCBV values correlate between newly diagnosed glioblastomas and the same tumors at first progression. We sought to minimize potential confounders by analyzing technically uniform data in a homogeneous patient cohort, as well as by adding histologic analysis for correlative analysis.This retrospective analysis was approved by the scientific board of the University Cancer Center Frankfurt and the local ethics committee (UCT-22-2020). All patients were cared for in our neuro-oncology department We screened our institutional database for patients meeting the following three criteria:IDH wildtype glioblastomaNeuropathologically confirmed diagnosis of an At least 18 years old at initial diagnosisDSC-perfusion measurements using identical protocols and acquired at the same 3 Tesla MRI scanner at both initial diagnosis and first time of progression. As a result of this criterion, recruitment was set to begin in January 2011, after a new 3 Tesla MRI scanner had been installed.When available, samples from patients who met these criteria and who had been treated surgically for their first glioblastoma progression were reevaluated neuropathologically. Both the primary and the progressive tumors were examined.® or Skyra®; Siemens, Erlangen, Germany). The anatomical MRI included T2-weighted sequences and T1-weighted sequences before and after administration of contrast agent. The acquisition parameters for the DSC-perfusion measurements were equal for both scanners . Measurements were performed either with or without application of a contrast agent pre-bolus before administering the intravenous main bolus . As specified above, the acquisition schemes had to be identical in individual patients for measurements at initial diagnosis and first progression. Measurements with insufficient contrast agent bolus according to the time-signal curves or severe motion artifacts were excluded.All examinations were conducted on 3 Tesla MRI scanners (Verio® software toolbox. The automated software uses the Boxerman–Weisskoff approach to assess brain perfusion curves that have been corrected for leakage of contrast agent into the tissue [max). An exemplary case is shown in The raw data of all perfusion measurements was homogeneously reanalyzed using the MR Neuro Perfusion application of the Philips IntelliSpacee tissue . The cal2) was calculated from the average number of vessels in three fields of view (FOV) at 20-fold  or 40-fold magnification  in the tumor area displaying the highest density of vessels. In addition, the dominating vessel size  and the dominating vessel wall characteristic  were recorded. An experienced neuropathologist (K.F.), who was blinded to the results of the MR-perfusion measurements, analyzed all available tissue samples, again consecutively rating all samples from initial diagnoses before rating the samples from first time of progression. Formalin-fixed and paraffin-embedded tumor tissue sections were stained with hematoxylin and eosin (HE) and assessed visually. The maximum vessel density  or a commercially available inhouse software called BiAS® (https://www.bias-online.de/). The Kolmogorov-Smirnov-Lilliefors test was used to test for normal distributions; the values for CBVmax and patient age followed normal distribution while all other variables did not. Differences in rCBVmax values and vessel densities between primary and progressive tumors were assessed either by the paired t-test or the Wilcoxon matched pairs test. Differences in the time to progression between subgroups were analyzed by Wilcoxon-Mann-Whitney-test. Correlations between the values measured in newly diagnosed and progressive glioblastomas were calculated using the Spearman’s rank correlation. Even for the rCBVmax values, that followed normal distribution, the assumption of a linear correlation as a prerequisite for the Pearson correlation did not seem to be appropriate and the Spearman’s rank correlation was used instead. A p-value of less than 0.05 was deemed to indicate significance.Statistical testing was done employing either SPSSWe identified 65 patients who fulfilled all inclusion criteria and whose DSC-perfusion measurements qualitatively met our requirements  promoter methylation. The diagnosis had been made after resection of the tumor in two cases and after biopsy in four cases. Chemotherapy (temozolomide) was administered in the first-line treatment of only two of the six patients; the other four were treated with radiation alone. The median overall survival of these six patients was 260 days (range 133–860).Fifty-two patients received the standard 6-week radiotherapy with a total dose of 60 Gy  In two pmax values measured in glioblastoma at initial diagnosis were significantly higher than the corresponding values in progressive tumors . Beyond the difference in rCBVmax magnitudes, there was no significant correlation between the rCBVmax values at initial diagnosis and progression .The rCBVmax values, the maximum vessel densities were significantly lower in progressive glioblastomas than in the corresponding newly diagnosed tumors . The dominant vessel size switched in 15/24 cases from initial diagnosis to first progression, mostly from small to medium. The dominant vessel wall characteristic changed in 8/24 patients, with none of the samples displaying a sclerosed/hyalinized vessel wall type either before or after first-line therapy.Tumor tissue samples from both the initial diagnosis (22 resections/ 2 biopsies) and the first progression  were available for 24 patients. Twenty-two of these patients had undergone adjuvant radiochemotherapy in between surgeries, two patients had not received adjuvant therapy. As for the rCBVmax increase in glioblastoma at initial diagnosis is a permanent tumor characteristic that can be retrieved when the tumor is regrowing or progressing.Our study addressed the question whether the extent of the DSC-perfusion derived rCBVmax from initial diagnosis to first progression. This finding was reflected by a simultaneous decrease in the histologic vessel density. Our subgroup analysis revealed that the reduction was mostly driven by patients who had undergone resection upon initial diagnosis and was not detectable in patients who had received a biopsy only  actually reporting an inverse correlation of tumor size and CBV [In accordance with the two studies reporting rCBV values in glioblastoma both at initial diagnosis and first progression ,27, we fpsy only . The rat and CBV .max also tend to have a marked hyperperfusion when they regrow. Yet, we did not find any correlation between the rCBVmax measurements from initial diagnosis and first progression Click here for additional data file.S2 Figmax) significantly (p < .001) decreasing from initial diagnosis to first progression in patients with initial resection but not in patients with biopsy only. Ladder-plots with individual rCBVmax values for every patient in the two subgroups and a red line indicating the mean (a). Missing correlations (Spearman’s rho = .12/.22) of the rCBVmax values at initial diagnosis and first progression in both subgroups displayed as scatter plots with regression lines (b and c).Relative cerebral maximum blood volume in the tumor (rCBV(TIF)Click here for additional data file.


Eukaryotes segregate their chromosomes during mitosis and meiosis by attaching chromosomes to the microtubules of the spindle so that they can be distributed into daughter cells. The complexity of centromeres ranges from the point centromeres of yeast that attach to a single microtubule to the more complex regional centromeres found in many metazoans or holocentric centromeres of some nematodes, arthropods and plants, that bind to dozens of microtubules per kinetochore. In vertebrates, the centromere is defined by a centromere specific histone variant termed Centromere Protein A (CENP-A) that replaces histone H3 in a subset of centromeric nucleosomes. These CENP-A nucleosomes are distributed on long stretches of highly repetitive DNA and interspersed with histone H3 containing nucleosomes. The mechanisms by which cells control the number and position of CENP-A nucleosomes is unknown but likely important for the organization of centromeric chromatin in mitosis so that the kinetochore is properly oriented for microtubule capture. CENP-A chromatin is epigenetically determined thus cells must correct errors in CENP-A organization to prevent centromere dysfunction and chromosome loss. Recent improvements in sequencing complex centromeres have paved the way for defining the organization of CENP-A nucleosomes in centromeres. Here we discuss the importance and challenges in understanding CENP-A organization and highlight new discoveries and advances enabled by recent improvements in the human genome assembly. Centromeres provide the site on each chromosome where spindle microtubules attach during cell division. The multiprotein complex known as the kinetochore assembles at the centromere and attaches to dynamic microtubules generating the primary binding interface between the chromosome and mitotic spindle fibers. The kinetochore nucleoprotein complex is necessary for chromosome orientation during metaphase, mitotic checkpoint activity, and segregation of daughter chromosomes during anaphase .Centromeres vary widely in their organization and structure between organisms but one shared function is their activity in generating a microtubule binding site. Chromatin in which the histone H3 variant, CEntromere Protein A (CENP-A), replaces histone H3 in a subset of centromeric nucleosomes determines the position of the active centromere and kinetochore . BuddingElectron micrographs of metaphase arrested human cells suggest that there are on average ∼20 kinetochore/microtubules attached at each centromere . Within The two essential centromere proteins that recognize and directly bind CENP-A nucleosomes—CENP-C and CENP-N—can both bind more than one nucleosome . Both CECentromere and pericentromere DNA make up ∼6% (189 Mb) of the genome . Centromin situ hybridization to identify centromere DNA sequence limits distinction between the highly similar repeat sequences at centromeres. Enrichment of CENP-A within a smaller portion of the active centromere has also been observed on neocentromeres i.e. de novo centromeres that form outside the canonical centromere  will receive fewer CENP-A nucleosomes in the next cell cycle, essentially doubling disparities in CENP-A levels between daughter cells. Tracking CENP-A deposition using pulse-labeling of exogenous SNAP-CENP-A shows poor correlation in the extent of asymmetric distribution of CENP-A nucleosomes to sister centromeres between consecutive cell cycles, suggesting that replicative distribution is not regulated to correct for low abundance of CENP-A nucleosomes . TherefoIn humans and other vertebrates, the histone chaperone HJURP binds a CENP-A:H4 dimer prior to CENP-A nucleosome assembly . Early ide novo (i.e. resulting from new CENP-A deposition) dinucleosomes to limit excessive deposition. Evidence for cell cycle regulated epigenetic modifications on CENP-A and centromeric H3 have been reported  but theCENP-A nucleosomes can be deposited outside centromeres on chromosome arms in G1, but cells clear these ectopic nucleosomes from non-centromere DNA during DNA replication . CENP-A While centromere sequences vary across chromosomes and between HORs, a common feature of all centromeres except chromosome Y in humans is the presence of a CENP-B box . The CENWith the completion of the human genome, investigations of the organization, inheritance, and maintenance of CENP-A chromatin at a single chromosome level is more within our reach than ever. The recent telomere-to-telomere genome assembly has identified unique markers within the highly homogenous HORs . Most un


Lobelia species that minimally required deletion of the plastid gene accD and five inversions to account for their plastome arrangement relative to the ancestral organization. Sixty alternative 5-step inversion scenarios could account for the observed arrangement, but only one scenario was consistent with the criterion of ‘common cause’ attributable to a putative rearrangement hot spot at the accD deletion-site. Plastome sequencing demonstrated that this previously hypothesized inversion order is historically accurate. Detailed reconstructions of the ancestral plastome organization before and after each inversion are presented herein. Stem-loop and disruption-rescue models were evaluated for each inversion. One inversion has an obvious stem-loop basis, but the other four inversions were primarily caused by serial insertion of foreign (extra-plastid) DNA bearing large open-reading frames that disrupted plastome organization at the accD deletion-site, and complete plastomes were rescued by seemingly arbitrary ligation or fortuitous recombination at the other inversion endpoint. Transposed copies of DNA segments from elsewhere in the plastome are frequently inserted at inversion junctions, and four junctions are consistent with the stem-loop ligation model.The evolution of plastid genomes (plastomes) in land plants is typically conservative, with extensive structural rearrangements present in only a few groups. Early Southern blot analysis identified two  Widespris lutea , but theg region .ycf2) has subsequently been identified. However, the intergenic regions of these scattered exemplars were generally too divergent for comparative analysis. Multiplexed ‘genome skimming’ with next-generation sequencing [The methodological shift to plastome gene sequencing provided a more effective community-based approach to estimating plant phylogeny , but genquencing ,7 providLobelia species originally studied in 1993, L. fervens and L. erinus had the most extensively rearranged plastomes. The derivation of this rearrangement pattern from a tobacco-like ancestral pattern [accD plus five large inversions. All Lobeliaceae lack accD, so this gene deletion was safely inferred to have been an early event , but the remaining three inversions could have occurred in various possible orders. If the first two inversions were synapomorphic with other Lobeliaceae, then the accD deletion-site was a common endpoint for both these inversions, and of the remaining alternative scenarios, only one consistently used the accD deletion-site as an endpoint for all five inversions. This additional criterion of ‘common cause’ was the basis for the hypothesized order of rearrangement events  region that separate the large single-copy (LSC) and small single-copy (SSC) regions , but thure 3 in ), and the S3C in ). This se S3C in , and thiLobelia fervens and L. erinus illustrate the complex alterations that have occurred at inversion and insertion junctions. Not all historical details can be unambiguously reconstructed because of dramatic subsequent alterations in descendent lineages. Broader comparison with the Campanulaceae and Cyphiaceae  to the intergenic spacer between trnC(GCA) and rpoB -rpoB region had seven of eight nucleotides that coincidentally matched the sequence flanking that stem-loop structure. Insertion of the transposed copy of rpl23 is inferred to have occurred via a single-stranded, stem-loop ligation model -rpoB intergenic DNA, was secondarily transposed to a site downstream of rbcL . This con model  at the uplastome . The verplastome  provideseliaceae , but it Lobelia baumannii-Colensoa clade occurred independently from the inversions in the rest of the Lobeliaceae, the first of which occurred in the common ancestral lineage of Monopsis and the remaining Lobeliaceae (Inversion 1 in psbA-trnK(UUU) intergenic region, (2) a 118-bp duplication of the 3′ end of ORF200 , (3) insertion of a large segment of foreign DNA inferred to have carried ancestral ORF148, (4) a 64-bp copy of the trnC(GCA)-rpoB intergenic spacer, and (5) a 45-bp tandem duplication of plastid DNA at the inversion endpoint upstream of psbA (psbA-trnK(UUU) intergenic region, where it then provided the molecular basis of a stem-loop inversion, but it seems more likely that this segment was duplicated during the plastome disruption caused by the insertion of ORF148. This insertion, along with the seemingly arbitrary ligation points in the psbA-trnK(UUU) intergenic region, which resulted in the 53-bp deletion and the 45-bp tandem duplication, is more consistent with the disruption-rescue model. It is possible that the ligation points represent sites of illegitimate recombination due to sequence similarity, but this hypothesis cannot be evaluated without knowledge of the foreign DNA sequences prior to integration into the plastome. The duplicative transposition of the 64-bp segment from the trnC(GCA)-rpoB region and the deletion that removed almost all remaining traces of accD may have occurred at the same time as the inversion, or they may have occurred at a later time during the same phylogenetic interval. The plastome of L. thermalis -ndhC intergenic region -trnK(UUU) junction lacks any obvious sequence element that was involved in the inversion. The small copied segment of the trnK(UUU) intron may be the remnant of a larger tandem duplication, which implies that the original junction with the trnV(UAC) downstream intergenic DNA was located somewhere downstream of this trnK(UUU) intron copy. A subsequent large deletion would account for the position and orientation of the trnK(UUU) intron copy, the missing 152 bp from the trnV(UAC)-ndhC intergenic region, the missing end of the hypothesized tandem duplication, and whatever DNA was previously present downstream of trnK(UUU). However, the abutment of the trnV(UAC) downstream intergenic DNA and the duplicated copy of the trnK(UUU) intron is not consistent with a slipped strand deletion event, and there are no matching sequences in the relevant ancestral trnV(UAC)-ndhC and trnK(UUU)-psaI regions that would have facilitated an inversion, so no ancillary evidence supports this hypothesis. If the original trnV(UAC)-trnK(UUU) junction is preserved, then this inversion is consistent with the disruption-rescue model, and the location of the transposed trnK(UUU) intron copy so close to the source is just coincidence.The inversion that occurred in the common ancestral lineage of c region . A smallon model . The jun of psaI . The trnLobelia fervens-L. laxa clade (Inversions 3 and 4 in rpoB-trnC(GCA) intergenic region  and a small remnant of ancestral ORF227. The rps12 intron 1B copy has five recently derived point mutations that are shared with the source region in L. laxa, which indicates that this was a very recent duplicative transposition in L. laxa or that the copy and the source region are undergoing concerted evolution. There is weak amino acid similarity among small segments at the 3′ ends of ORF236, ancestral ORF308, and ancestral ORF227, but if ORF236 is a recombination product of ancestral ORF308 and ancestral ORF227, then a very complex set of events must be hypothesized to account for the ORF227 remnant located farther downstream. This inversion is more consistent with the disruption-rescue model, where the rescue was accomplished by recombination of the two copies of the 3′ end of rpl23 into a single copy. In the stem-loop model of inversion, both stems are preserved. Lobelia laxa is the only known species that is sister to the L. fervens-L. erinus clade, so there is no immediate phylogenetic opportunity to investigate the timing of events in the L. laxa lineage.The order of the two inversions shared by the c region . An almoeliaceae . Most ofl ORF308 . One junersion 2 . The othtrnG(UCC)-trnR(UCU) and trnC(GCA)-psaI intergenic regions, with no associated insertions, deletions, or duplications (rpoB-trnC(GCA) intergenic region  intergenic region in L. laxa has insertions of foreign DNA and transposed copies of plastid DNA (rpl23 remnant and the flanking foreign DNA from the rpoB-trnC(GCA) intergenic region  intergenic region. The stem-loop structure may have promoted recombination at this site, but this was not a stem-loop inversion. The other inversion junction has a newly formed stem-loop at the end of the intergenic plastid DNA upstream of rps4 and extensive deletions and insertions that have continued after divergence of the L. fervens and L. erinus lineages. As a result of this DNA trafficking, only a 300-bp core in ORF180 and ORF188 remains from ORF236, and the remaining foreign DNA and some of the flanking plastid intergenic DNA from the rps4-trnT(UGU) and trnR(UCU)-psaI regions has been replaced by new insertions. Because ORF125 is intact in L. fervens and some plastid DNA from the rpoB-trnC(GCA) intergenic region (trnR(UCU) in this species (following Inversion 4), the lineage leading to L. erinus is inferred to have sustained more extensive and recent alterations. However, DNA trafficking also appears to have continued in the lineage leading to L. fervens, as evidenced by the transposed copy of rps12 intron 1B and the flanking intergenic plastid DNA. The source of this duplicative transposition overlaps the source of the rps12 intron 1B copy in L. laxa, but the location of the copy is different. The rps12 intron 1B copy in L. fervens has four recently derived point mutations that are shared with the source region in L. fervens, which indicates that this was a very recent duplicative transposition in L. fervens or that the copy and the source region are undergoing concerted evolution. Lobelia fervens and L. erinus are part of a large, rapidly diversifying clade that provides ample phylogenetic opportunity to study the most recent alterations by sequencing the plastomes of related species.The inversion shared by the stid DNA  that canc region  that wasc region  is stillWith an appropriate phylogenetic context, ancestral DNA sequences can be reconstructed at the beginning and end of each phylogenetic interval. When evolutionary changes in the descendent lineages are relatively modest, ancestral sequences are confidently reconstructed and DNA ambiguity codes adequately represent the few positions at which a nucleotide differs between sister clades and these differ from the nucleotide present at the start of a phylogenetic interval. Although alignment gaps are commonly referred to as ‘indels’ (shorthand for insertions/deletions), bona fide insertions are rare in angiosperm plastomes  and a beThe inserted foreign DNA in the Lobeliaceae (and Campanulaceae and Cyphiaceae) is commonly associated with transposed copies of DNA from elsewhere in the plastome , and manrpoB-trnC(GCA) intergenic region in a position and orientation that is plausibly explained only if Inversion 3 preceded Inversion 4. This small segment is preserved in Lobelia laxa  region prior to Inversion 5 -rpoB intergenic region (Not all foreign DNA insertions caused inversions, and not all inversions were caused by foreign DNA insertions. The ancestral ORF200 is inferred to have been inserted at or near the ion-site  without ion-site . Similarc region  and otheGrammatotheca bergiana (Lobelia hartlaubii relative to L. baumannii undergoes concerted evolution, and it is likely that the intervening 34-kb has flip-flopped repeatedly [Lobelia heterophylla and L. linearis have independent 5-kb inversions in the IR caused by inverted 15-bp segments that coincidentally match [The reversion in bergiana  has a moTransposed copies of DNA from elsewhere in the plastome provide important historical information. Secondary transpositions that overlap a junction from a primary transposition (or subsequent insertion; cf. rpl23 play recurrent roles in the plastome rearrangements, being one of the early shared events in the ancestral lineage with the Campanulaceae and Cyphiaceae (rpl23 recombined into a single copy and cannot be considered the primary cause of Inversion 3.Primary and secondarily transposed partial copies of phiaceae , providiphiaceae , and serphiaceae . Unlike Small stem-loop structures also appear to have a recurrent role in plastome rearrangements, both as breakage points and ‘molecular jigs’ for ligation . The preWithout knowing the source sequence of the inserted segments of foreign DNA it is not possible to analyze fully their junctions with plastid DNA. Comparative plastome mapping delimits the endpoints of the plastid DNA, beyond which the DNA is unambiguously of extra-plastid origin. However, it is possible that a foreign DNA segment started with sequence that coincidentally matched the plastid DNA, with illegitimate recombination and/or stem-loop ligation partially accounting for how the foreign DNA integrated into the plastome. When stem-loop structures form or are enlarged at plastid/foreign junctions e.g., , circumsLobelia fervens and L. erinus suggests that more extreme alterations within this clade remain to be discovered—perhaps species that have additional inversions. Four of the five inversions documented herein are consistent with the disruption-rescue model, with one endpoint located at the inversion hot spot located at the accD deletion-site. However, the “accD deletion-site” describes what is not present, not what is present. This inversion hot spot is characterized by serial replacement of foreign DNA at a site upstream of psaI that is adjacent to a large stem-loop structure. The quintessential feature of this hot spot seems to be the foreign DNA trafficking, but to what extent is the adjacent stem-loop structure involved? Inversion 5 separated these two features (L. fervens-L. erinus clade may answer this question.The source of the inserted foreign DNA is not yet known but is most likely the nucleus . The prefeatures , and theInferred ancestral sequences were reconstructed from multiple sequence alignments of previously sequenced plastomes . Each in


BackgroundSupracondylar elbow fractures occur most frequently in children aged five to seven years and have equal incidence in both genders. They are classified as flexion or extension type injuries with extension type being more common. We aimed to ascertain radiological stability with lateral and crossed wires in this study. We also identified any complications after operative management of these injuries.MethodsAs part of this retrospective cohort study, we identified all patients who presented with this injury from January 1, 2020, until February 28, 2022. Basic demographic data and type of operation were noted. Baumann angle (BA) and lateral capitellohumeral angle (LCHA) were measured intra-operatively and x-rays were done at the final clinic appointment. The mean of these angles in lateral and crossed wire groups was compared using paired sample t-test. Unpaired t-test was used to compare the means of both groups with normal values for these angles based on previous studies .ResultsFifty patients were admitted during this period. Thirty-three patients had lateral wires and 17 had crossed wires for fixation. No significant change was noted in the mean BA and mean LCHA in both groups on x-rays done intra-operatively and final clinic follow-up (no loss of reduction). No significant difference was noted between BA and LCHA noted for both groups at the final clinic follow-up with previous studies outlining normal values for these angles. No cases of iatrogenic neurovascular injury were identified. Four patients (8%) were referred to physiotherapy due to stiffness.ConclusionBoth lateral and crossed wire configurations led to achievement of good radiological stability with BA and LCHA within normal limits. No loss of reduction was noted with both techniques and no risk of iatrogenic nerve injuries was noted in experienced hands. Supracondylar elbow fractures are a common injury in the paediatric population and account for 60% of elbow fractures in this demographic . SkeletaClosed reduction and percutaneous pinning with K-wires is the treatment of choice for grade 2 and above supracondylar fractures. Two or three K-wires can be inserted as all lateral or crossed configuration. Crossed K-wires are reported to have greater rotational rigidity compared to lateral pins but have been reported be more likely associated with ulnar nerve injuries -7.The primary aim of our study was to compare the radiological stability of supracondylar fractures treated with lateral and crossed K-wires using Baumann angle (BA) and lateral capitellohumeral angle (LCHA) measured intra-operatively and at the final clinic follow-up. In addition, we secondarily assessed patient demographics, common mechanisms of injury, duration of clinic follow-up, and post-operative complications in both groups.Study designThis was a retrospective cohort study where we obtained data regarding all paediatric patients admitted with supracondylar elbow fractures from January 1, 2020, until February 28, 2022. Data were collected on a secure Microsoft Excel sheet. This study was classified as an audit and permission from the local audit and quality improvement department at Altnagelvin Area Hospital, Derry/Londonderry. A formal ethics approval or institutional review board approval was not required as this was deemed a retrospective cohort study in line with recommendations from National Health Service Health Research Authority (NHS HRA) regulations.Inclusion and exclusion criteriaPaediatric patients between the age of two to 12 years presenting with supracondylar elbow fractures who were surgically managed were included in the study. Children managed non-operatively were excluded from the study. Also, we excluded children with other elbow fractures such as lateral or medial epicondyle fractures, olecranon fractures, and those requiring open reduction and internal fixation. We also excluded patients for whom further clinic follow-up was planned at the time of data collection.Data collectionThe local theatre management system (TMS) coordinators provided a list of patients who fit the inclusion criteria. Demographics, admission, and follow-up data were obtained from the patient records available through the Northern Ireland Electronic Care Record (NIECR). The Northern Ireland Picture Archiving and Communication System (NIPACS) was used to obtain accurate measurements of the angles used to assess fracture stabilisation.DefinitionsBaumann angle (BA), also known as the capitellohumeral angle, is formed by the humeral axis and a line drawn through the epiphyseal plate of the capitellum. It is a measure of coronal plane alignment in supracondylar fractures. The lateral capitellohumeral angle (LCHA) is the angle between humeral shaft and the capitellum on lateral x-rays of the elbow and is a measure of the sagittal plane alignment . The norFractures were classified as flexion-type and extension-type. Extension-type fractures were further classified according to modified Gartland classification as per Wilkins and Leitch et al. Table  3,4,15],4,153,4,For convenience, grade 2 fractures were not further classified as part of the study. The mechanism of injury was classified as per Table Data variables collectedBasic demographic variables included gender and age. Laterality of the fracture was also noted. The mechanism of injury was recorded as per Table Configuration of K-wires was noted on intra-operative x-rays as all lateral versus crossed wires. K-wires of 2 mm were used in our centre to fix these injuries. Additionally, we recorded the number of wires inserted for stabilisation of the fracture. We also noted number of clinic follow-ups required, number of days to removal of K-wires, and number of days till removal of cast.Operative complications noted included iatrogenic neurovascular injury, pin site infection, and presence of significant stiffness requiring referral to physiotherapy services. BA and LCHA were measured on intra-operative x-rays and x-rays taken at the final clinic follow-up.Data analysisAs part of achieving our primary aim for this study, we used Statistical Package for the Social Sciences (SPSS) version 25  to compare mean BA and LCHA at time of operation; and mean BA and LCHA at final clinic appointment in groups treated with lateral or crossed K-wires using paired t-test to ascertain the comparison between stabilisation afforded by both the techniques. We also performed a chi-square test to identify an association between configuration of wires and number of wires used.As part of our secondary aims, we used an unpaired t-test to compare mean BA and LCHA at the final clinic appointment in both lateral and crossed wire groups with normal values for these angles as per Shank et al. . We compDemographic and baseline characteristicsBaseline characteristics and demographic data are listed in Table A chi-square test was performed to ascertain an association between configuration of wires and number of wires used. The relation between these variables was significant χ2  =14.2751, p<0.001. Patients treated with crossed K-wires were more likely to have three K-wires inserted. Mean time to surgery from the initial x-ray was 16.04 hours with a standard deviation of 10.97 hours (range= 2-58 hours).Stabilisation of fracture (primary aim)The mean BA and LCHA measured intra-operatively and at time of final clinic follow-up did not vary significantly in both the groups treated with crossed and lateral wires. This would suggest that the fractures treated with both lateral and crossed wires maintained stability throughout the period of fracture healing and follow-up. Table Fracture fixation compared to normal values of BA and LCHAOur study found no significant difference between the mean BA and LCHA measured on x-rays at final clinic follow-up compared to the normal values in uninjured elbows as per Shank et al. . The onlFollow-up outcome dataThe odds of having significant stiffness requiring referral to physiotherapy were greater in crossed wire group compared to lateral wire group OR=6.86) but this was not statistically significant (p=0.1081). There was no significant difference noted in the comparison of mean time to removal of wires in lateral versus crossed wire groups. The time to removal of cast and mobilisation was noted to be significantly longer in crossed wire group. This is further elaborated in Table .86 but tSupracondylar humeral fractures are commonly seen in children, and they are reported to be the second most common injury in children . Our datWe noted in our study that the mean BA and LCHA at time of final X-rays were not statistically significant compared to mean BA and LCHA measurements taken intra-operatively after fixation of fracture. Previously it has been reported that higher degree of torsional stress is needed to deform fractures fixed with crossed wires compared to lateral wires, but this remains a controversial topic . Other sOur study had limitations in terms of a small number of patients due to which some data did not reach statistical significance such as the presence of higher stiffness in patients managed with crossed wires leading to a greater need for referral to physiotherapy. Nevertheless, the study gives further evidence to the notion that excellent results can be achieved with both lateral and crossed wires in management of supracondylar elbow fractures in children even though we note that the BOAST guidelines report lower risk of loss of reduction with use of crossed wires . We recoBased on radiological follow-up, lateral and crossed K-wiring techniques for supracondylar elbow fractures lead to superb construct stiffness which in turn provides stability to the fracture site during the healing process. In experienced hands, the incidence of post-operative complications such as iatrogenic nerve injury is also low compared to previously available data.


We present experimental demonstration of tilt-mirror assisted transmission structured illumination microscopy (tSIM) that offers a large field of view super resolution imaging. An assembly of custom-designed tilt-mirrors are employed as the illumination module where the sample is excited with the interference of two beams reflected from the opposite pair of mirror facets. Tunable frequency structured patterns are generated by changing the mirror-tilt angle and the hexagonal-symmetric arrangement is considered for the isotropic resolution in three orientations. Utilizing high numerical aperture (NA) objective in standard SIM provides super-resolution compromising with the field-of-view (FOV). Employing low NA (20X/0.4) objective lens detection, we experimentally demonstrate  In the rapidly progressing area of nanoscopy, structured illumination microscopy (SIM)7 appears as a significant widefield super-resolution technique where a series of structured patterns are employed to excite the fluorescent sample and corresponding raw Moiré frames are computationally processed to achieve around two-fold resolution enhancement over the widefield limit. In spite of offering relatively moderate resolution enhancement in comparison to the other optical super-resolution techniques, such as stimulated emission depletion (STED),9 stochastic optical reconstruction microscopy (STORM),11 photo activated localization microscopy (PALM),13 or ground state depletion (GSD),15 SIM has drawn considerable attention due to its high spatio-temporal resolution, low photo-toxicity, compatibility with common fluorescent labelling, efficient multi-colour imaging17 and so on. It is also considered a promising approach for the investigation of the sub-cellular dynamics of living cells19 for its requirement of less number of raw frames and low photon-dose. Although sinusoidal structured excitation pattern is the key feature to achieve the superior resolution imaging through SIM, it is no longer restricted to the periodic illumination patterns. Speckle-like21 random illuminations with blind reconstruction approaches are also successfully implemented for the SIM imaging. However, the random illumination methods offer super-resolution at the cost of low temporal resolution due to the requirement of a large number of frames  and therefore deals with 2D imaging only. Besides, the saturation properties of the fluorescent materials are harnessed in the nonlinear-SIM28 approach which incorporates the contributions of multiple harmonics in super-resolution imaging. However, the requirement of high intensity to reach the operating saturation level of the fluorophores can provide photo-toxicity issues for the non-linear approach. Further SIM techniques based on different principles have also been reported, e.g., plasmonic30, proximity projection grating31 or photonic chip32. Each of these techniques requires sophisticated and dedicated photonic or plasmonic materials to manipulate the structured illumination pattern in the sample plane. In addition, specially designed tools are required for the phase-shifting and changing pattern orientation, e.g., thermo-optics for photonic chip SIM or galvo-scanning for the plasmonic SIM. In general, these techniques are complex due to their dependence on the dedicated material; which restricts the tunability of the illumination pattern frequency. In plasmonic SIM, the pre-calibrated array structures are fabricated according to the operating wavelength range. The specific structure selectively determines the orientation and the frequency of the illumination pattern, there is no tunability of the pattern. Similarly, in photonic chip SIM, the illumination pattern frequency is pre-decided by the angles of the available waveguide arms. Finally, conventional samples on microscope slides or coverslips do not work for these methods. It is required to prepare the sample on the surface of the designed material which is illuminated by the standing waves interference pattern in the evanescent regime, restricting these techniques to 2D-TIRF super-resolution.In the conventional linear SIM technique, a single objective lens is employed for illuminating the sample as well as for collecting the fluorescence signal. Consequently, both the illumination and the detection optics are diffraction limited by the same objective lens, and the system is strictly restricted to offer 34. Recently, a theoretical approach35 was reported to overcome this limitation by decoupling the illumination path from the collection path using a transmission type tilt-mirror configuration. Nevertheless, the technique is not experimentally demonstrated for the bio-imaging application with scalable FOV and scalable resolution imaging. Herein, we demonstrate the experimental proof-of-concept of the tilt-mirror assisted transmission type SIM technique which possesses potential to exploit the high throughput SIM utilizing the free space optics in a cost-effective way. Liberating the illumination optics from the diffraction limit of the collection objective lens facilitates the full flexibility to play with the illumination configuration. This is, to the best of our knowledge, also the first experimental proof that describes it being possible to design the illumination for large FOV nanoscopy without guiding the light through any condenser lens36, waveguide chip34 or advanced materials38.In the race of achieving the best possible resolution, high numerical aperture objective lenses are typically utilized for the SIM imaging. The super-resolution image in SIM employing the high NA objective lens is obtained by compromising with the field of view (FOV). This limitation appears because of the inherent trade-off between the resolution and the FOV of the standard imaging system. Because of this dependence, the next level super-resolution techniques have been dealing with large FOV imaging while improving the resolutionDecoupling the illumination from the detection optics in transillumination microscopy architecture paves the way to explore the versatile illumination modalities. In this work, we present a proof-of-principle experimental demonstration of transillumination SIM technique where an assembly of mini tilt-mirrors work as the illumination module. As the excitation path becomes independent of the collection path, the maximum frequency of the illumination pattern is no longer restricted by the detection objective lens.z) upon reflection by a pair of tilt-mirrors. The tilt angles of the oppositely faced mirror pair are adjusted in such a way that the reflected beams overlap in a small volumetric region to generate a sinusoidal interference pattern. At an instant, a pair of tilt-mirrors becomes functional for collecting the first diffraction orders from the grating. It is required to incorporate grating rotation and corresponding collection of the diffracted orders by other pairs of tilt-mirrors for isotropy. The purpose of the condenser lens is effectively fulfilled by the set of tilt-mirrors. This unique lensless illumination scheme possesses potential benefits in generating aberration free structured pattern which is homogeneous over the entire volume of interference. Besides, the area of illumination is no longer limited by the condenser lens; rather it is decided by the diameter of the interfering beams described in supplementary text T1. The sample is kept within the volumetric region to illuminate with the excitation pattern and a standard upright microscope is employed to collect the fluorescent signal from the other side of the sample. The maximum spatial frequency support of the transillumination SIM technique is determined by considering the resultant contributions from the detection and the illumination configuration,n. Hence, the theoretical lateral resolution limit of the tilt-mirror based tSIM is determined as,The graphical representation of the experimental setup is shown in Fig. mentclass2pt{minimmentclass2pt{minimmentclass2pt{minimmentclass2pt{minimmentclass2pt{minimmentclass2pt{minimmentclass2pt{minimThe major advantage of the tSIM technique comes into play when the large field of view imaging is concerned, where a low-magnification/low-NA objective lens is utilized for the detection. Without modifying the detection passband (keeping the objective lens fixed), it is possible to incorporate illumination pattern of any arbitrary frequency with a maximum limit of mentclass2pt{minimmentclass2pt{minimIn order to validate the super-resolution capability of the proposed tilt-mirror assisted structured illumination microscopy, we present experiments for polymer beads as well as a biological cell sample. For the proof-of-concept, first we demonstrate the experimental results for a scenario similar to the conventional SIM case where the illumination frequency lies within the passband limit of the detection system. A CW laser of wavelength 532 nm  is used as the excitation light source throughout the study.39 is applied to process the raw tSIM data. The reconstructed image of the fluorescent beads and corresponding diffraction limited widefield image are shown in the Fig. The interfering beams are overlapped at the semi-angle of interference entclass1pt{minimaentclass1pt{minimaentclass1pt{minimaentclass1pt{minimaentclass1pt{minimaentclass1pt{minimaentclass1pt{minimaentclass1pt{minima39 is implemented in this example as well, with the widefield and corresponding reconstructed tSIM image shown in Fig. Further, we explore the feasibility of the technique for a real application through a biological specimen. U2OS (human bone osteosarcoma) cells are seeded on glass coverslips, permeabilized, stained for actin filaments, and sealed with another glass coverslip on top. The 20X/0.4 objective lens is again employed here to simultaneously record more than 50 cells within the large FOV (0.56 mm width and 0.35 mm height). The sample imaging is performed in a region of interest where the concentration of the cells are moderate. The raw moiré frames are acquired under the identical imaging conditions as described for the case of the fluorescent beads. The reconstruction algorithm ‘OpenSIM’40 suffer to process the raw data in this particular case as the illumination frequency exists outside the passband support. This is overcome by utilizing a TIRF-SIM like reconstruction approach39. The reconstructed and corresponding widefield image is shown in Fig. So far we have shown tSIM results with traditional illumination conditions. Now, we present an example where tSIM surpasses the conventional linear SIM resolution gain of two-fold, performed by implementing high frequency illumination with the pattern frequency outside the detection passband limit. The angle of the tilt-mirrors are tuned in such a way that the semi-angle of interference becomes All the previous discussion revolves around low-NA collection, large FOV imaging, tunable illumination patterns and corresponding super-resolution. However, it is mentioned that the overall resolution appears from the joint contributions of illumination and detection. Finally, the super-resolution capability of the tSIM utilizing the high-magnification/high-NA detection objective is demonstrated. We switch to 100X/1.3 oil immersion (Olympus) objective lens for the collection of the fluorescent signal while keeping the other imaging components  same as described for the previous cases. The same sample  is used in this case also. The semi-angle of interference is kept Thus, employing high-NA detection objective lens improves the resolution of the detection system and applying tSIM further brings the resolution scale down to and entclass1pt{minima41 approaches for our reconstruction, however, there are possibilities to explore blind43 approaches which do not require the prior knowledge of the illumination patterns. Moreover, the deep-learning based45 algorithms might offer potential application in the tSIM reconstruction. The proof-of-principle experimental demonstration of tSIM for the fluorescent beads provides the perfect result. However, the reconstruction of the actin filaments contains some sort of honeycomb artifacts46 which is due to photo-bleaching and poor signal to noise ratio. Such reconstruction imaging artefacts are common in standard SIM image, however, the fluorescence is bright and stable for the beads sample and such artefacts were not observed. The feasibility of tSIM is justified with high-NA detection objective lens with the resolution down to In conclusion, we demonstrate the proof-of-concept experimental results of tilt-mirror assisted transmission structured illumination microscopy (tSIM) which makes the illumination and the detection optics flexible to configure them independent to each other. The tilt-mirror facilitates to generate illumination patterns with tunable frequencies, which are of potential importance in order to provide the resolution gain depending upon the requirement. Employing the low-NA detection, a single large FOV image of size 0.56 mm47. Nevertheless, there is a scope to extend the proposed technique suitable for the 3D-SIM48 imaging by allowing the central beam into the tSIM architecture. In conventional SIM systems, the illumination and the collection is coupled and thus to obtain the small fringe period , the two interfering beams should hit the edge of the back aperture of a given objective lens. Thus, every time a new objective lens is used for imaging, the optical arrangement must be changed to utilize the highest spatial frequency supported by the different objective lenses. Consequently, the commercial SIM system usually comes with a pre-defined single objective lens of high magnification and NA. This restricts the FOV of commercial SIM system to about 2. The tSIM supports both the large and the user-defined FOV by simply swapping to another detection objective lens without influencing the illumination light path. The large FOV support of tSIM will find applications where high-throughput is essential such as in the histopathology50. Similarly, tSIM will benefit neuroimaging applications where data must be correlated both in space and time by imaging large areas51.The system is very compact in comparison to the typical SIM systems. The system at present takes The coverslip was rinsed with diluted acetone and cleaned with deionized water. Next, it was treated with isopropyl alcohol solution and again cleaned with deionized water. Then, it was dried with the compressed nitrogen gas. A small (0.5 μl) amount of 200-nm diameter fluorescent bead solution  was pipetted out and poured gently onto the cleaned coverslip. The coverslip was then kept at an inclined position and then allowed to dry completely. In this kind of drying, gravity pulls the droplet and the upper edge down during the liquid evaporation, which reduces the ‘coffee ring effect’. A tiny drop of glycerol was placed on another coverslip of bigger length; touching one edge of the coverslip containing beads with the bigger coverslip, the other edge was lowered slowly until it became completely flat on the glycerol. During this process, the sample side of the small coverslip faced towards glycerol so that the sample became sandwiched between two coverslips. The glycerol was allowed to spread out without pressing and the boundary between two coverslips was sealed with nail paint. After drying the paint, the sample was put under microscope for imaging.2. Cells (15–20% confluence) were seeded on #1.5 glass coverslips  for 20 min at room temperature (RT) to label f-actin in the cells. Three times wash in PBS before mounting with ProLongOsteosarcoma U2OS cells were cultured in Dulbecco’s modified eagle medium  supplemented with 10% fetal bovine serum (Sigma-Aldrich) and 1% penicillin/streptomycin (Sigma-Aldrich) at 37 degree with 5% COThe raw moiré frames were recorded using an upright modular microscope . The emission filter used for the imaging is the 550 nm long-pass fluorescent filter (Semrock). The rotation of grating was done using a motorized rotation stage (Holmarc). The physical grating was mounted on a single-axis translation stage and this stage including grating were attached together with the rotation stage. The linear piezo-translation stage  is operated along a particular direction to introduce suitable phase-shifting to the illumination pattern and a sequence of frames are recorded correspondingly. The acquisition process is repeated for three different orientations by revolving the grating around the optic axis using the rotation stage .The computational image processing i.e. the reconstruction steps are performed only using MATLAB R2020b executed in a computer workstation running Windows 10 (Intel Xeon(R) W-2175 CPU, 2.50 GHz, RAM 64GB). First, the raw dataset is drift corrected through a custom-written algorithm. Then open-source package (Open-SIM) is employed to obtain the super-resolution image from the drift-corrected data. The associated code called TIRF-SIM in the same package is utilized for the reconstruction of data where the illumination frequency lies beyond the detection passband.Supplementary Information.


Robot-assisted spine surgery aims to improve the accuracy of screw placement. We compared the accuracy and safety between a novel robot and free hand in thoracolumbar pedicle screw placement.Eighty patients scheduled to undergo robot-assisted (40 patients) and free-hand (40 patients) pedicle screw placement were included. The patients’ demographic characteristics, radiographic accuracy, and perioperative outcomes were compared. The accuracy of screw placement was based on cortical violation and screw deviation. Safety outcomes mainly included operative time, blood loss, revision, and complications.P < 0.001). The rate of clinically acceptable screw position (grades A and B) was also higher in the robot-assisted group than in the free-hand group . The robot-assisted group had significantly lower screw deviation than the free-hand group . There was no robot abandonment in the robot-assisted group. No revision was required in any of the groups.A total of 178 and 172 screws were placed in the robot-assisted and free-hand groups, respectively. The rate of perfect screw position (grade A) was higher in the robot-assisted group than in the free-hand group (91.0% vs. 75.6%; Robot-assisted pedicle screw placement is more accurate than free-hand placement. The second-generation TiRobot–assisted thoracolumbar pedicle screw placement is an accurate and safe procedure.Trial registration retrospectively registered Pedicle screw fixation is the most commonly used internal fixation method in thoracolumbar spine surgery , 2. It pTiRobot system, a multiple-indication surgical robot developed by Beijing Jishuitan Hospital and Beijing TINAVI Medical Technologies, has achieved good results in clinical orthopedic surgeries –15. In aThe purpose of this study was to compare the accuracy and safety between the second-generation TiRobot and free hand in thoracolumbar pedicle screw placement.This retrospective study recruited patients scheduled to undergo thoracolumbar pedicle screw placement in our hospital between December 2020 and June 2021. The study was approved by the Ethics Committee of Beijing Jishuitan Hospital (Number: 201911-05-01), and informed consent was obtained from all patients.The inclusion criteria were as follows: (1) scheduled for thoracolumbar pedicle screw placement; (2) age over 18 years; (3) willingness to participate in the study. The exclusion criteria were as follows: (1) previous surgical history of thoracolumbar spine; (2) active infection; (3) presence of scoliosis greater than 20°; (4) history of spinal tumors or tuberculosis.Two groups of patients undergoing thoracolumbar pedicle screw placement were retrospectively included. The patients were divided into the robot-assisted (RA) group and the free-hand (FH) group depends on whether the robot was used intraoperatively. RA or FH surgery was chosen by the patient after the surgeon clarified the details of both procedures. All thoracolumbar pedicle screw placements were performed by the same team of spine surgeons. Each surgeon performed the same amount of both surgeries. The RA group comprised patients (n = 40) consecutively treated under robot-assisted surgery. The FH group comprised patients (n = 40) consecutively treated using fluoroscopy-guided FH surgery.The robot-assisted procedures were performed using the second-generation TiRobot system . This robot inherits the precision advantage of the previous generation and makes the surgical procedure more efficient through the “intelligent surgical module” design Fig. . A newlyThe robot-assisted procedures were performed in accordance with the “guideline for thoracolumbar pedicle screw placement assisted by orthopedic surgical robot ” Fig. 22. The C-Cortical violation was evaluated on postoperative computed tomography (CT) by two doctors blinded to this study according to the Gertzbein and Robbins scale , as follScrew deviation was measured by comparing the actual guidewire positions to the planned guidewire positions  through merging the postoperative CT images with the planning images at the same depth in the axial and sagittal planes , 10, 13 Information about the operating time, intraoperative blood loss, complications, robot abandonment, and revision surgeries was recorded and compared.t test and Mann–Whitney U test (continuous variables) were used to evaluate statistical differences. In all of the statistical analyses, P < 0.05 was considered statistically significant.Statistical analysis was performed using SPSS software . The normality of distribution for continuous variables was verified using the Shapiro–Wilk test. The Chi-square test and Fisher’s exact test  or Student’s A total of 178 pedicle screws were placed in the RA group, while a total of 172 pedicle screws were placed in the FH group. There was no statistically significant difference in age, gender, and body mass index between the groups (Table P < 0.001). The rate of clinically acceptable screw position (grades A and B) was also higher in the RA group than in the FH group . The RA group had significantly lower screw deviation than the FH group   was higher in the RA group than in the FH group  mL vs. 300  mL, P = 0.439]. There was no robot abandonment in the RA group. No revision surgeries and screw-related complications were noted in any of the groups  min vs. 120 90, 135) min, 5 min, P The present study compared the accuracy and safety between RA and FH pedicle screw placement. The main finding is that the RA technique with an upgraded robot system was superior to the FH technique in terms of cortical violation and screw deviation.Previously, we investigated clinical application of the TiRobot orthopedic robot in cervical and thoracolumbar surgery in prospective randomized controlled studies. The results showed that the accuracy and safety of the robot in cervical spine internal fixation were better than those of the FH surgery, with the perfect screw position rate of 87.6% and a screw deviation of 0.83 mm . The accHowever, the use of TiRobot to perform pedicle screw placement has some shortcomings: (1) Before three-dimensional image scanning, an image registration calibrator needs to be installed, and fluoroscopy is required to ensure that the marking points on the calibrator are captured by the anteroposterior–lateral images at the same time; (2) A special individual is required to handle the main control station to control the robot; (3) The tracker in the end of the robotic arm has a single-plane design, leading to a limited tracking angle.Through the collaborative innovation by doctors and engineers, the second-generation TiRobot system was developed. Its main upgrades are as follows: (1) integration of the image registration calibrator with the C-arm, which reduces the difficulty of image registration to save operation time; (2) surgeons can directly click the touch screen in the main control station and the operating button in the robotic arm to fully control the robot; (3) the 360-degree omnidirectional tracer in the robotic arm is easier to be recognized by the optical tracking system, which reduces operation time of adjusting the position of optical tracking devices. A review of the literatures found that the clinical outcomes of second-generation TiRobot were similar to first-generation TiRobot.In our study, more screws had the perfect position and clinically acceptable position in the RA group than in the FH group. The higher accuracy achieved in the RA group is consistent with previous reports. Fatima et al.  performeAlthough one of the purposes of the improvements of the second-generation TiRobot is to shorten the operation time, this effect was not reflected in this study. This is our first 40 cases of second-generation TiRobot-assisted spine surgery. It is possible that the operation time was not shortened due to the early learning curve required by the surgeon to adapt to the new human–computer interface. Future studies with larger samples are needed to confirm whether the use of this robot can actually shorten the operation time.The present study had some inherent limitations. Firstly, this study was a retrospective analysis of radiological and perioperative outcomes. Follow-up assessments are needed to assess the long-term outcomes. A multicenter prospective study with a larger sample size is needed to verify the findings of this study. Secondly, this study did not directly compare the clinical outcomes of second-generation TiRobot with first-generation TiRobot, and further in-depth research is needed in the future.Robot-assisted pedicle screw placement is more accurate than FH placement. The second-generation TiRobot-assisted pedicle screw placement is an accurate and safe procedure in thoracolumbar spine surgery.


IntroductionReverse shoulder arthroplasty (RSA) is becoming increasingly popular as a primary procedure for complex proximal humeral fractures (PHF) in acute trauma due to more emerging evidence and better patient outcomes.MethodsThis study is a retrospective case series of 51 patients who underwent a trabecular metal RSA for non-reconstructable, acute three or four-part PHF performed by a single surgeon between 2013 and 2019 with a minimum follow-up of three years. This included 44 females and seven males. Mean age was 76 years (range: 61-91 years). Oxford shoulder score (OSS) along with relevant patient information relating to demographics and functional outcomes were collected at regular intervals in outpatient clinic follow-ups. Complications were addressed accordingly during treatment and follow-up.ResultsThe mean follow-up duration was 5.08 years. Two patients were lost to follow-up and nine patients died due to other causes. Four of them had developed severe dementia and were excluded as an outcome score from them could not be acquired. Two patients who had surgery beyond four weeks post-injury were excluded. Thirty-four patients in total were followed up. Patients had good range of motion and mean OSS of 40.28 post-operatively. The overall complication rate was 11.7%, and none of the patients had deep infections, scapular notching, or acromial fractures. Revision rate was 5.8% at mean follow-up of five years and one month (range: three years to nine years two months). Greater tuberosity union following intra-operative repair was evident on radiographs in 61.7% of the patients.ConclusionRSA is certainly a rewarding surgery in patients with complex PHF and was associated with good post-operative OSS along with patient satisfaction, and positive radiological outcomes at minimum three-year follow-up. The prevalence of proximal humerus fractures (PHF) accounts for around 4-10% of all fractures as reported in several studies conducted in different populations [Most of the minimally displaced fractures are managed conservatively. Displaced three or four-part fractures, particularly in elderly patients, present with challenges. Reconstruction of these fractures with poor bone quality is associated with avascular necrosis and a high incidence of implant failure. Hemiarthroplasty is an option in these patients, but functional results are unpredictable; this is largely due to a deficiency of tuberosity healing including migration, resorption, and malunion . The emeBiomechanically, the glenohumeral joint of the shoulder is a multiaxial ball and socket articulation between the humeral head, and a shallow pear-shaped bony glenoid to permit a wide range of motion . The shaWhile in reverse shoulder arthroplasty, the anatomy is reversed to a glenoid ball (glenosphere) and concave proximal humerus component . The desThis was a retrospective case series (Level of Evidence IV). Fifty-one consecutive Trabecular metal shoulder replacements following trauma from 2013 to 2019 were enrolled in the study. This study was exempt from the National Health Service (NHS) Research Ethics Committee review with Integrated Research Application System (IRAS) project ID #323730.Inclusion criteria were un-reconstructible, acute three or four-part proximal humerus fractures (PHF) with or without dislocation Figure . PatientPatients in the age range of 61-91 years were included in the study, with the mean age being 76 years. This figure included 44 females (86%) and seven males (14%). Majority of these elderly patients had one or more major medical co-morbidities including diabetes mellitus, hypertension, ischemic heart disease, or chronic kidney disease. Eighteen percent (n=9) of the patients were either previous or current smokers.Nine patients died from other conditions during follow-up. Two patients were lost to follow-up. Four of them had developed severe dementia and were excluded as an outcome score from them could not be acquired. Two patients who had surgery beyond four weeks post-injury were excluded. The reasons for the delay in operation were due to patients taking longer time to decide on treatment options and the lack of theatre slots available on trauma lists. We considered injuries less than four weeks old as acute since there was little scarring found during dissection and hence no effect on results. The study included a total of 34 patients.All operations were performed in beach chair position reclined at 30 degrees with support under the scapula, with a mechanical arm holder  under general anesthetic and regional nerve blocks. Deltopectoral approach was used. Long head of biceps (LHB) and rotator interval were identified. LHB was tenodesed to pectoralis major. Greater and lesser tuberosities with cuff attachments were identified and debulked, but bony attachments were retained to promote tuberosity healing and held with a stay suture. Comminuted and devitalized humeral head fragments were removed. We used the Zimmer Biomet Trabecular metal reverse shoulder system .The glenoid was prepared first, with the arm held in external rotation at the shoulder. Trabecular metal baseplate was positioned over the glenoid with inferior translation and tilt to achieve least rocking forces during shoulder movements . It was Trabecular metal reverse humeral stem was used Figure . This isThe proximal part of the stem had a trabecular metal coating that came in contact with the tuberosities to promote bony ingrowth. In cases with severe comminution, insertion of pectoralis major was used as a guide to achieve the correct height and tension. Two drill holes were made in the shaft to reattach the tuberosities. A pair of non-absorbable looped sutures were also passed from each of the tuberosity fragments onto the holes in the proximal part of the stem. Tuberosities were approximated to the shaft first with a "nice sliding knot" and then tied together.The ease of approximation was an indication of adequate height and correct polyethylene insert size for the humeral component. Patients were placed in a polysling for four weeks, seen by the physiotherapist on the ward, and followed up in the community. In the first four weeks after the operation, patients were allowed to start with active range of motion exercises for elbow and hand and passive forward elevation of shoulder. Polysling was discarded at four weeks and active assisted range of motion was commenced up until the sixth post-operative week. Active range of motion of the shoulder was started after week six.All patients were followed up in the clinic at three months, six months, one year, and then annually with follow-up radiographs. Oxford shoulder scores (OSSs) were collected during the follow-up visits to the clinic. We have used the last scoring obtained from the patient to assess outcome at the longest follow-up period post-operatively. All patients had shoulder antero-posterior view, scapular "Y" view, and an apical oblique or axial view Figure . TuberosThe mean age was 76 years (range: 61-91 years of age). The majority of patients in the cohort were females 86% (n=44) with 14% males (n=7). Fifty-five percent of injuries were left-sided (n=28), and 45% of injuries were right-sided (n=23). The final analysis included 34 patients. Seventeen patients were excluded from this study. The time from the date of injury to operation ranged from one to 28 days, with a mean of 10.5 days. Length of hospital stays ranged from one to 28 days, with a mean of five days. The procedure was carried out by a single surgeon at a single center. Mean follow-up duration was five years and one month (range: three years to nine years two months).Range of motion was assessed clinically, and Oxford shoulder scores (OSSs) were obtained at final follow-up Table . Mean OSEarly complications of superficial infection, urinary tract or respiratory tract infections, acute delirium or acute kidney injury were prevalent in seven 20.5%) patients (Table 0.5% patiFour patients (11.7%) developed late complications which included aseptic loosening, peri-prosthetic fracture, or dislocation Table . ComplicOne patient with dislocation had initially presented four weeks post-injury with axillary nerve palsy. A second patient dislocated their shoulder five weeks after the operation following a fall and trauma to the operated shoulder. Both dislocated shoulders were revised with a new liner but redislocated again after six weeks. Both patients refused further intervention due to the risks involved with multiple surgeries.One patient had a peri-prosthetic fracture distal to the tip of stem (Wright and Cofield type C) following a fall on the operated side eight months after surgery . The patThe overall revision rate was 5.8%. We did not encounter any scapular notching, acromial fractures, or base plate failures in our patient series. Thirty patients (88%) said they thought this operation was a success and would recommend it to other patients.Treatment of displaced three or four-part fractures has always been challenging . Even wiReverse shoulder arthroplasty (RSA) has gained popularity in all parts of the world as a treatment option for these fractures as they do not rely on tuberosity fixation and healing. The success of reverse shoulder arthroplasty is biomechanically based on increasing the moment arm of the deltoid muscle. This is possible as the center of rotation of the glenohumeral joint is moved medially and inferiorly Figure . This alOur study was from a case series of 51 patients from a single center. All cases were under a single surgeon and included a minimum of three years of follow-up, with an average period of follow-up being five years and one month. The range of motion achieved by patients, tuberosity healing, and complications in the long-term follow-up were comparable with other studies reported in the literature Table .Bufquin et al. in a retrospective case series assessed the clinical outcome of reverse shoulder arthroplasty (RSA) in 43 elderly patients over 65 years of age with comminuted proximal humerus fractures (PHF) . They diDezfuli et al. in their case series of 49 patients compared RSA for acute PHF, malunion or non-union, failed PHF hemiarthroplasty, and failed PHF fixation . They coVillodre-Jiménez et al. found that RSA is a valid option to treat three and four-part proximal humerus fractures (PHF) in elderly patients . The surWright et al. from their study with a 56-month follow-up of uncemented stems in RSA said that cement may not be necessary for the trauma setting . Cuff etBarbosa et al. at a minimum two-year follow-up concluded that there were no significant differences in outcomes between patients with healed and reabsorbed tuberosities . Jain etLimitations of our study are that this is a case series and only 67% of patients were followed up to three years. More prospective long-term studies will better highlight the benefit of this increasingly popular procedure for treatment of proximal humerus fractures (PHF) in elderly patients.The results of the current study are good and similar in comparison to other studies. Un-reconstructible proximal humerus injury can be debilitating if left untreated, and so reverse shoulder arthroplasty is certainly a rewarding surgery. Improved implant designs including modularity and advanced surgical techniques have continued to provide good outcomes in elderly low-demand patients. Through further long-term prospective studies, longevity of reverse shoulder arthroplasty in younger patients, implant survival rate, mode of failure of components, and revision techniques are to be explored in the future.


In hyperscanning studies of natural social interactions, behavioral coding is usually necessary to extract brain synchronizations specific to a particular behavior. The more natural the task is, the heavier the coding effort is. We propose an analytical approach to resolve this dilemma, providing insights and avenues for future work in interactive social neuroscience.The objective is to solve the laborious coding problem for naturalistic hyperscanning by proposing a convenient analytical approach and to uncover brain synchronization mechanisms related to human cooperative behavior when the ultimate goal is highly free and creative.This functional near-infrared spectroscopy hyperscanning study challenged a cooperative goal-free creative game in which dyads can communicate freely without time constraints and developed an analytical approach that combines automated behavior classification (computer vision) with a generalized linear model (GLM) in an event-related manner. Thirty-nine dyads participated in this study.Conventional wavelet-transformed coherence (WTC) analysis showed that joint play induced robust between-brain synchronization (BBS) among the hub-like superior and middle temporal regions and the frontopolar and dorsomedial/dorsolateral prefrontal cortex (PFC) in the right hemisphere, in contrast to sparse within-brain synchronization (WBS). Contrarily, similar regions within a single brain showed strong WBS with similar connection patterns during independent play. These findings indicate a two-in-one system for performing creative problem-solving tasks. Further, WTC-GLM analysis combined with computer vision successfully extracted BBS, which was specific to the events when one of the participants raised his/her face to the other. This brain-to-brain synchrony between the right dorsolateral PFC and the right temporo-parietal junction suggests joint functioning of these areas when mentalization is necessary under situations with restricted social signals.Our proposed analytical approach combining computer vision and WTC-GLM can be applied to extract inter-brain synchrony associated with social behaviors of interest. Second-person neuroscience considers the dynamic interplay between multiple brains and has become a burgeoning field of interest.,,Early fNIRS hyperscanning studies adopted experimentally controlled tasks that may not be sufficiently naturalistic, such as simultaneous motor action,This study addresses this problem by proposing an analytical approach for naturalistic fNIRS hyperscanning. This methodological consideration was the first objective of this study. We used “computer vision” for automated behavior estimation from video-recordings. To examine the relationship between automatically extracted behaviors and particular neuronal synchrony, a generalized linear model (GLM) was applied in an event-related manner. This method can estimate which social signal correlates with which type of brain synchronization, in addition to the ordinarily performed condition-based analysis.The second objective of this study was to uncover brain synchronization mechanisms related to human cooperative behavior when the ultimate goal of cooperation is highly free and creative. The cooperative tasks used in previous fNIRS hyperscanning studies generally have in common that they have relatively fixed goals that are known in advance, such as pressing a button at the same time as much as possible or completing a Jenga game together.,–,,,,–,,,This study designed a free-style joint creative computer game to capture dynamic aspects of naturalistic social interaction. Two players were asked to design the interior of a room that satisfied both parties or just themselves, without limitations on time or communication. The two conditions (cooperative and independent) were compared to reveal between- and within-brain synchronized (WBS) activities specific to each condition. Furthermore, from global brain synchronizations elicited by cooperative creation, we attempted to extract those corresponding to particular social behaviors . The facial orientation of a participant, roughly comparable to the presence/absence of eye gaze, contains active social cues to the partner.Our study proposes an analytical approach without manual behavioral coding to extract the neural correlates of targeted social signals (face-to-face). With this approach, we sought to uncover behavior-specific brain synchronizations among various interactive social behaviors and neural synchrony elicited by a task demanding collaborative creation without time constraints.22.1A total of 78 college students  participated in the experiment. This resulted in 39 same-sex dyads . Five participants were left handed. None of the participants reported sensory, neurological, or psychiatric disorders. Written informed consent was obtained from all participants following the Declaration of Helsinki. The experimental protocol was approved by the Ethics Board of Keio University, Japan (No.16028).2.2Supplementary Material). The dyad sat face-to-face and manipulated their touch panels . This strict classification threshold selected The pitch angle was transformed into a Supplementary Material) to be used as regressors in the following GLM analysis. This procedure extracted the temporal information of (1) when both participants raised face (“both-up”) and (2) when only one participant  raised face (“self-up” for participant A and “other-up” for participant B).Face-up events were labeled in the two COOP sessions  were used as dependent/response variables. The WTC of one representative frequency band  in an event-related manner. WTCs that showed significantly larger values , the time courses of the aforementioned three types of face-up events serving as regressors were linked to the time course of the WTC for each representative ch-ch-fr. First, the time courses of the behavioral regressors  of the deoxy-Hb were nearly the same as that of oxy-Hb with some differences in statistical values .We will report our oxy-Hb results here and provide relevant information about the deoxy-Hb data in Fig. S3 in the 3.1Supplementary Material).Significantly stronger BBS . As shown in A representative selection of ch-ch-fr for the WBS, using the same method as BBS, yielded 52 representative ch-ch-fr showing significant differences .Significant synchronizations shown in 3.2The results above for BBS of oxy-Hb revealed significantly stronger synchronization in COOP than in IND for many channel-pairs. The GLM analysis further elucidated how these synchronizations were specifically related to particular social behaviors such as face-up events. Comparison of rection] . In othe4This study used fNIRS hyperscanning to investigate the neural correlates of cooperative creation during an unrestricted turn-based computer game with changeable goals. We proposed an approach to extract particular neuronal synchronization related to specific social communicative signals among various behaviors elicited in such a goal-free task. Specifically, we used an automatic behavioral detection technique to mark epochs with targeted social behaviors (face-up) and then examined the relationship between face-up behaviors and neuronal synchronization using a GLM. WTC analysis revealed distinct patterns of brain synchrony in different situations: joint play induced greater BBS among the rSTG, rMTG, rFP, and rDMPFC/rDLPFC across the two brains, whereas independent play induced stronger WBS among similar regions within a single brain. WTC-GLM analysis showed that BBS between the rDLPFC and rTPJ of two brains was significantly more related to the behavior when only one participant raised his/her face than when both members raised their faces.4.1,Conventional WTC analysis revealed that joint play elicited significantly stronger BBS in many channel-pairs , left, i4.2,,,Supplementary Material). Therefore, our results on BBS in the MTG/STG regions were not directly related to speech but may be neural correlates of the cognitive process for creative tasks.What specific cognitive processes do the BBS between MTG/STG and FP/DLPFC reflect during COOP? Several recent single-brain studies have reported the involvement of the MTG region in creativity-related tasks.,–,,,,,Although rarely reported as neural-coupling in the PFC in previous studies, there has been an increase in recent reports of synchronization in the FP,Most previous fNIRS hyperscanning studies focused on brain synchronization in the same channels of dyads. Recent research also discovered synchrony between different channels/regions.In summary, the significantly stronger BBS in the FP/DLPFC of two brains and that projecting between the FP/DLPFC of one brain and the MTG/STG of the other brain may be neural indicators for (1) endeavors for creative problem solving of the dyads toward an abstract shared goal (to create a room that satisfies both parties) and (2) information exchange during such cooperation that requires constantly attending to and reading others’ intentions.4.3As we adopted a task allowing nearly unconstrained interaction, various social behaviors would have been associated with the large number of synchronized channels obtained using conventional WTC analysis. To clarify the specific relationships between certain types of interactive behavior and certain types of brain synchrony, we applied GLM to the WTC results (WTC-GLM) in an event-related manner, wherein the events were social behaviors extracted automatically using computer vision. We chose face-up events as the target behavior because it should approximately correspond to eye gaze, reflecting a person’s thoughts or intentions.Supplementary Material). No significant correlation was found, so our WTC-GLM results were unlikely to be related to the motion synchronization of face-up behaviors. We suppose that this BBS is related to the mentalization process. TPJ is a broad region inclusive of SMG, AG, and posterior STG (pSTG), which serves as a crucial part of the MENT,,,,,–A comparison of the WTC-GLM results between the both-up and either-up regressors extracted one significant between-brain channel-pair (CH4 and CH14 corresponding to rDLPFC and rTPJ) with a synchronization that was more related to the either-up regressor . To evalIn light of this evidence, one possible explanation for the stronger relationship between the BBS of rTPJ and rDLPFC and the either-up regressor is as follows. When both members raised their faces (both-up), they were better able to understand each other’s intentions and feelings via facial information, whereas facial information exchange is largely limited to one direction during either-up so that more effort is required to infer the partner’s  intention by observing facial information (functioning of the rTPJ) and adjust one’s (participant A) own mind and behavior accordingly (functioning of the rTPJ). Meanwhile, participant B noticed/attended to this gaze (functioning of the rDLPFC), understood participant A’s thought, and adjusted his/her own idea and behavior (functioning of the rDLPFC) to design a room that also satisfied participant A. Further analysis partly supports this assumption. The WTC time series between the rDLPFC and rTPJ was aligned with the timing of both-up events (the “0” point) . It showInterestingly, the synchronization between the rTPJ (CH14) of the two brains and between the rTPJ of one brain and the rDLPFC (CH4) of the other brain was significantly stronger during independent play , right. Supplementary Material). This result excludes the possibility that the specific neural synchronization related to the face-up regressor is biased toward a certain game behavior. Rather, the observed relationship between social behavior and neural synchronization is universal in the present naturalistic cooperative setting.Additionally, the occurrence rate of both-up and either-up events in the four types of behavior logs  during COOP showed no significant difference . Although many BBS showed a significant relationship with vocalization, there was no overlap of channel-pair between COOP-related BBS and vocalization-related BBS. These results support that the brain synchronizations during COOP do not directly reflect speech factors. Furthermore, we also confirmed that the ratio of vocalization in the either-up periods was not significantly different from that in the both-up or “other” periods . This suggests that either-up specific BBS (rTPJ and rDLPFC) was unlikely to relate to speech factors. It is worth noting that our audio-recording quality prevented us from dissociating the identity and content of speech. Future studies with higher quality audio-recording may provide further insights into speech factors.One could claim that a limitation of our study is a difference in the speech condition between COOP and IND. However, this study aimed to examine natural interaction for creative goal-free task and to explore a method of detecting behavior-specific synchronization in natural states, so we prioritized naturalness by allowing speech during COOP. We do not deny a possibility that stronger BBS during joint play was due to various interactive signals including speech. Regardless, it is interesting that the BBS during COOP showed similar brain connections to those of WBS during IND, which did not include speech. To examine the possible impact of speech, we additionally applied our WTC-GLM paradigm to isolate vocalization-related synchronization from WTC during COOP (Sec. 2.2 in the 5Our cooperative creativity task induced robust BBS that could be characterized as functioning in a two-in-one system. This brain-coupling, represented as dynamic interplays of the STG/MTG regions and the FP/DLPFC regions between the two brains, was assumed to reflect cooperative creative problem solving. Notably, WBS was largely restricted during this mode, probably due to the endeavor to adjust one’s mind and behavior to the partner. Furthermore, we uncovered the underlying relationship between certain neural correlates and specific social behaviors among numerous brain synchronizations by combining GLM analysis with automatic behavioral detection. Our proposed analytical approach may provide insights and avenues for future work in interactive social neuroscience.Click here for additional data file.