Observing many researchers using the same data and hypothesis reveals a hidden universe of uncertainty

This study explores how researchers' analytical choices affect the reliability of scientific findings. Most discussions of reliability problems in science focus on systematic biases. We broaden the lens to emphasize the idiosyncrasy of conscious and unconscious decisions that researchers make during data analysis. We coordinated 161 researchers in 73 research teams and observed their research decisions as they used the same data to independently test the same prominent social science hypothesis: that greater immigration reduces support for social policies among the public. In this typical case of social science research, research teams reported both widely diverging numerical findings and substantive conclusions despite identical start conditions. Researchers' expertise, prior beliefs, and expectations barely predict the wide variation in research outcomes. More than 95% of the total variance in numerical results remains unexplained even after qualitative coding of all identifiable decisions in each team's workflow. This reveals a universe of uncertainty that remains hidden when considering a single study in isolation. The idiosyncratic nature of how researchers' results and conclusions varied is a previously underappreciated explanation for why many scientific hypotheses remain contested. These results call for greater epistemic humility and clarity in reporting scientific findings.

Brain MR Imaging of Patients with Perinatal Chikungunya Virus Infection

Since 2005, it has been known that mother-to-child transmission of the chikungunya virus is possible. Transmission generally occurs in the perinatal period. In the present study, we describe the brain lesions seen on MR imaging of 6 cases of perinatal chikungunya infection. Patients who underwent brain MR imaging in the acute phase presented with areas of restricted diffusion in the white matter, suggesting a perivascular distribution, whereas those in the subacute/late phase showed cystic lesions, also with a perivascular distribution, with or without brain atrophy. One patient also presented with scattered hemorrhages in the frontal and parietal lobes. Important differential diagnoses include rotavirus, Parechovirus, herpes simplex infection, and hypoxic-ischemic encephalopathy, depending on the disease phase.

Can a brief psychological intervention improve oral health behaviour? A randomised controlled trial

Background

Dental caries is a major public health issue affecting a large proportion of the general population. The disease is associated with behavioural factors and is thus preventable to a high degree. Individuals may need assistance to be able to change their oral health behaviour. There is a lack of such interventions for adults affected by severe caries. The aim of the study was to evaluate the effect of Acceptance and Commitment Therapy (ACT), a form of cognitive behavioural therapy, on oral health behaviour in young adults with poor oral health.

Methods

The study included a two group parallel randomised controlled trial at general dental clinics, with young adults, 18–25 years of age, ≥ two manifest proximal dental caries lesions (n = 135); 67 were treated with ACT and 68 with standard disease information only, respectively. Primary outcomes: oral health behaviours (tooth-brushing, flossing, use of toothpicks, and additional fluoride use). The CONSORT principles for RCTs were used, including intention-to-treat and per protocol analyses. The Chi-square, Mann-Whitney, and Wilcoxon Signed Rank tests were applied, including effect sizes.

Results

The study groups did not differ with regard to oral health behaviour variables at baseline. The intervention group improved all their oral health behaviours significantly over time (effect sizes, 0.26–0.32), while the control group showed improved behaviours on two measures (flossing and additional use of fluoride, effect sizes, 0.22–0.23).

Conclusions

By testing a psychological intervention on young adults (18–25 years of age) with a high prevalence of caries, we found an immediate positive effect with improved oral health behaviours.

Trial registration

TRN ISRCTN15009620, retrospectively registered 14/03/2018.

A novel heterozygous IGF-1 receptor mutation associated with hypoglycemia

Mutation in the insulin-like growth factor-1 receptor (IGF1R) gene is a rare cause for intrauterine and postnatal growth disorders. Patients identified with IGF1R mutations present with either normal or impaired glucose tolerance. None of the cases described so far showed hypoglycemia. We aimed to identify the genetic basis for small for gestational age, short stature and hypoglycemia over three generations in one family. The proband, a 9-year-old male, presented in infancy with recurrent hypoglycemic episodes, symmetric intrauterine growth retardation and postnatal growth retardation. Blood DNA samples from the patient, his parents, a maternal sister and maternal grandmother underwent Sanger sequencing of the IGF1R gene. Primary skin fibroblast cultures of the patient, his mother and age- and sex-matched control donors were used for gene expression and receptor functional analyses. We found a novel heterozygous mutation (c.94 + 1g > a, D1105E) affecting the splicing site of the IGF1R mRNA in the patient, his mother and his grandmother. Primary fibroblast cultures derived from the patient and his mother showed reduced proliferation and impaired activation of the IGF1R, evident by reduced IGF1R and AKT phosphorylation upon ligand binding. In conclusion, the newly identified heterozygous missense mutation in exon 1 of IGF1R (D1105E) results in impaired IGF1R function and is associated with small for gestational age, microcephaly and abnormal glucose metabolism. Further studies are required to understand the mechanisms by which this mutation leads to hypoglycemia.

The Emerging Role of the Insulin-like Growth Factors in Oral Biology

The insulin-like growth factors (IGF) are a family of growth factors, receptors and binding proteins that are involved in numerous growth and differentiation processes, as well as in various pathological conditions. The aim of this review is to summarize data that has been accumulating in recent years linking the IGF system to a number of physiological and pathological oral processes. The IGF system fulfills an important role in growth and development of teeth, mandible, maxillae, and tongue. It has been postulated that IGF-I may be of great value in the treatment of periodontal defects and in tissue healing. Furthermore, IGF-II has been shown to be overexpressed in salivary gland adenomas, suggesting that aberrant IGF signaling may be a key factor in the etiology of oral malignancies. Understanding the role and regulation of IGF system components in salivary glands and other oral structures will be of significant basic and clinical relevance.

Method of Stimulus Presentation and Apparent Body Position under Lateral Body Tilt

Eighty Ss, 40 male and 40 female, indicated by means of a luminescent rod the location of their longitudinal body axis (apparent body position) under body tilt ranging from 90° left (counterclockwise), through upright, to 90° right (clockwise). The luminescent rod was presented by two psychophysical methods: (a) the method of limits and (b) the method of constant stimuli. Deviations of apparent from objective body position showed significant differences between the two methods. The results were interpreted in terms of an organismic theory of perception, utilizing the notion of a dynamic body schema as spatial reference system which was subject to modifications due to the method of stimulus presentation.

Psychological Interventions for Poor Oral Health

The aim of this systematic review and meta-analysis was to study the effectiveness of psychological interventions in adults and adolescents with poor oral health. The review follows the PRISMA guidelines for systematic reviews. The PICO format (population, intervention, comparison, and outcome) was used to define eligible studies. The populations were adults or adolescents (≥13 y of age and independent of others) with poor oral health (defined as dental caries, periodontal disease, and/or peri-implantitis). The interventions were psychological and/or behavioral models and theories, in comparison with traditional oral health education/information. The primary outcomes were dental caries, periodontitis, gingivitis, and peri-implantitis. Secondary outcomes were dental plaque, oral health–related behavior, health-related quality of life, health beliefs and attitudes, self-perceived oral health, and complications/risks. The systematic literature search identified 846 articles in December 2013 and 378 articles in July 2015. In total, 11 articles on 9 randomized controlled trials were found to meet the inclusion criteria. These reported on adults with periodontal disease, and several used motivational interviewing (MI) as their mode of intervention. The CONSORT guidelines and the GRADE approach were used for study appraisal and rating of evidence. The meta-analysis showed no statistically significant differences in gingivitis or plaque presence. In addition, a meta-analysis on MI compared with education/information found no statistically significant differences in gingivitis presence. Only 1 meta-analysis—on psychological interventions versus education/information regarding the plaque index—showed a small but statistically significant difference. There were also statistically significant differences reported in favor of psychological interventions in oral health behavior and self-efficacy in toothbrushing. However, the clinical relevance of these differences is difficult to estimate. The certainty of evidence was low. Future research needs to address several methodological issues and not only study adults with periodontal disease but also adolescents and patients with dental caries and peri-implantitis.

The thyroid hormone-αvβ3 integrin axis in ovarian cancer: regulation of gene transcription and MAPK-dependent proliferation

Ovarian carcinoma is the fifth common cause of cancer death in women, despite advanced therapeutic approaches. αvβ3 integrin, a plasma membrane receptor, binds thyroid hormones (L-thyroxine, T4; 3,5,3'-triiodo-L-thyronine, T3) and is overexpressed in ovarian cancer. We have demonstrated selective binding of fluorescently labeled hormones to αvβ3-positive ovarian cancer cells but not to integrin-negative cells. Physiologically relevant T3 (1 nM) and T4 (100 nM) concentrations in OVCAR-3 (high αvβ3) and A2780 (low αvβ3) cells promoted αv and β3 transcription in association with basal integrin levels. This transcription was effectively blocked by RGD (Arg-Gly-Asp) peptide and neutralizing αvβ3 antibodies, excluding T3-induced β3 messenger RNA, suggesting subspecialization of T3 and T4 binding to the integrin receptor pocket. We have provided support for extracellular regulated kinase (ERK)-mediated transcriptional regulation of the αv monomer by T3 and of β3 monomer by both hormones and documented a rapid (30-120 min) and dose-dependent (0.1-1000 nM) ERK activation. OVCAR-3 cells and αvβ3-deficient HEK293 cells treated with αvβ3 blockers confirmed the requirement for an intact thyroid hormone-integrin interaction in ERK activation. In addition, novel data indicated that T4, but not T3, controls integrin's outside-in signaling by phosphorylating tyrosine 759 in the β3 subunit. Both hormones induced cell proliferation (cell counts), survival (Annexin-PI), viability (WST-1) and significantly reduced the expression of genes that inhibit cell cycle (p21, p16), promote mitochondrial apoptosis (Nix, PUMA) and tumor suppression (GDF-15, IGFBP-6), particularly in cells with high integrin expression. At last, we have confirmed that hypothyroid environment attenuated ovarian cancer growth using a novel experimental platform that exploited paired euthyroid and severe hypothyroid serum samples from human subjects. To conclude, our data define a critical role for thyroid hormones as potent αvβ3-ligands, driving ovarian cancer cell proliferation and suggest that disruption of this axis may present a novel treatment strategy in this aggressive disease.

Shorter time since inflammatory bowel disease diagnosis in children is associated with lower mental health in parents

AIM

This study assessed the mental health of parents of children with inflammatory bowel disease (IBD), compared their mental health with age-matched and gender-matched references and examined parental and child predictors for mental health problems.

METHODS

A total of 125 mothers and 106 fathers of 125 children with active and inactive IBD from the Swiss IBD multicentre cohort study were included. Parental mental health was assessed by the Symptom Checklist 27 and child behaviour problems by the Strengths and Difficulties Questionnaire. Child medical data were extracted from hospital records.

RESULTS

While the mothers reported lower mental health, the fathers' mental health was similar, or even better, than in age-matched and gender-matched community controls. In both parents, shorter time since the child's diagnosis was associated with poorer mental health. In addition, the presence of their own IBD diagnosis and child behaviour problems predicted maternal mental health problems.

CONCLUSIONS

Parents of children with IBD may need professional support when their child is diagnosed, to mitigate distress. This, in turn, may help the child to adjust better to IBD. Particular attention should be paid to mothers who have their own IBD diagnosis and whose children display behaviour problems.

Synthese und Struktur von C5Me5Pd(PR3)X: Palladiumkomplexe mit einem unsymmetrisch gebundenen Pentamethylcyclopentadienylring [1] / Synthesis and Structure of C5Me5Pd(PR3)X: Palladium Complexes with an Unsymmetrically Bonded Pentamethylcyclopentadienyl Ring [1]

The complexes C5Me5Pd(PR3)X (1-4) are prepared from [Cl(PR3)Pd]2(μ-OCOCH3)2 and TIC5Me5. Attempts to replace the halide ligand by a second C5Me5 or a C5H5 unit remained unsuccessful. The X-ray structure analysis of C5Me5Pd[P(i-Pr)3]Cl (3) indicates that the five-membered ring shows a tendency of η1-bonding towards the metal.

Notizen: A Palladium — Assisted Generation of Fulvene

Palladium -fulvene complexes of the type [Pd(η2- R2C:C5H4)L2] may be prepared by reacting monosubstituted-η5 -cyclopentadienyl-palladium-η3-allyl complexes with tertiary phosphines

Iridiumkomplexe des Vaska-Typs mit Triisopropylphosphan-Liganden [1]

The complexes trans-[IrClL(PiPr3)2] (L = CO , py, CH3CN) were prepared from [(C8H14)2lrCl]2 via[IrCl(PiPr3)2] as intermediate. rrans-[IrCl(CO)(PiPr3)2] reacts with LiC2Ph to form trans- [IrC2Ph(CO)(PiPr3)2] which on treatment with HX produces [IrH X(C2Ph)(CO)(PiPr3)2] (X = Cl, CF3CO2). The trifluoroacetate ligand is displaced by iodide to give [IrHI(C2Ph)(CO)(PiPr3)2]. trans-[IrCl(N2)(PiPr3)2] is obtained from the carbonyl complex and 2-furfurylazide.

Osmiumisonitril-Komplexe mit Os-H-, Os-CH3- und Os-Au-Bindungen [1] / Osmiumisonitrile Complexes Containing Os-H. Os-CH3 and Os-Au Bonds [1]

The complexes C6H6Os(PMe3)CNR (R = Me, t-Bu, p-Tol, Ph) are prepared from [C6H6OsI(PMe3)CNR]PF6 and NaC10H8. They behave as metal bases and react with NH4PF6, CH3I and ClAuPPh3 to form salts of the corresponding cations [C6H6OsX(PMe3)CNR]+ where X is H, CH3 and AuPPh3, respectively. The reactions of [C6H6OsX(PMe3)CNR]PF6 (X = I, H, CH3) with excess PMe3 lead to displacement of the benzene ring and formation of the complexes trans-[OsX(CNR)(PMe3)4]PF6.

Der Mechanismus einer neuen Synthese von Aromaten- und Triolefin-metall-tricarbonylen aus Diolefin-metall-tetracarbonylen

Kinetische Untersuchungen über den Mechanismus der Bildung von Verbindungen L′M (CO)3 (M=Cr, Mo; L′=Aromat, Triolefin) aus LM(CO)4 (L = Norbornadien) belegen, daß die Reaktionsgeschwindigkeit sowohl von der Konzentration als auch von der Art von L′ abhängt. Die Interpretation der Ergebnisse unter Zugrundelegung des Bodenstein- Theorems läßt erkennen, daß als einleitender Schritt der Umsetzung die partielle Lösung der Diolefin-Metall-Bindung in LM (CO)4 anzunehmen ist. Im Fall L′=Triolefin ergibt sich ein additives Geschwindigkeitsgesetz mit einem Term zweiter Ordnung, d. h. hierbei erfolgt primär neben der Dissoziation auch ein direkter Angriff von L′ auf das Zentralatom des Ausgangskomplexes.

Virtual bronchoscopy for evaluating cervical tumors of the fetus

We report on four cases of fetal cervical tumor, comprising three lymphangiomas and one teratoma, evaluated by ultrasound and magnetic resonance imaging (MRI) between 26 and 37 weeks' gestation. The aim was to investigate the use of virtual bronchoscopy to evaluate fetal airway patency in each case. A three-dimensional (3D) model of the airway was created from overlapping image layers generated by MRI. The files obtained were manipulated using 3D modeling software, allowing the virtual positioning of observation cameras, adjustment of lighting parameters and creation of simulated 3D movies for analysis of a virtual path through the model. In all fetuses, fetal airway patency was clearly demonstrated by virtual bronchoscopy and this was confirmed postnatally. MRI with virtual bronchoscopy could become a useful tool for studying fetal airway patency in cases of cervical tumor.

Global methylation analysis identifies PITX2 as an upstream regulator of the androgen receptor and IGF-I receptor genes in prostate cancer

The insulin-like growth factor-I (IGF-IR) and androgen (AR) receptors are important players in prostate cancer. Functional interactions between the IGF-I and androgen signaling pathways have crucial roles in the progression of prostate cancer from early to advanced stages. DNA methylation is a major epigenetic alteration affecting gene expression. Hypermethylation of tumor suppressor promoters is a frequent event in human cancer, leading to inactivation and repression of specific genes. The aim of the present study was to identify the entire set of methylated genes ("methylome") in a cellular model that replicates prostate cancer progression. The methylation profiles of the P69 (early stage, benign) and M12 (advanced stage, metastatic) prostate cancer cell lines were established by treating cells with the demethylating agent 5-aza-2'-deoxycytidine (5-Aza) followed by DNA microarray analysis. Comparative genome-wide methylation analyses of 5-Aza-treated versus untreated cells identified 297 genes overexpressed in P69 and 191 genes overexpressed in M12 cells. 102 genes were upregulated in both benign and metastatic cell lines. In addition, our analyses identified the PITX2 gene as a master regulator upstream of the AR and IGF-IR genes. The PITX2 promoter was semi-methylated in P69 cells but fully methylated (i. e., silenced) in M12 cells. Epigenetic regulation of PITX2 during the course of the disease may lead to orchestrated control of the AR and IGF signaling pathways. In summary, our results provide new insights into the epigenetic changes associated with progression of prostate cancer from an organ confined, androgen-sensitive disorder to an aggressive, androgen-insensitive disease.

Nonsuppurative encephalitis in a dog

A 4-year-old male German Hunting Terrier presented with tremor, dyspnea, trismus, spasms of the musculature of the larynx and pharynx, and hypothermia and subsequently died despite intensive clinical care. Prior clinical signs included vomitus and diarrhea. Microscopic examination of the brain revealed a multifocal nonsuppurative brain stem encephalitis; a few intralesional neurons contained intranuclear inclusions. By immunohistochemistry, Aujeszky disease virus (Suid herpesvirus 1) antigen was detected in neurons in the brain and in ganglion cells of the trigeminal ganglia. Viral culture of brain tissue confirmed the presence of Aujeszky disease virus. Histopathologic findings in the brain with the identification of Aujeszky disease virus by immunohistochemistry and polymerase chain reaction are consistent with Aujeszky disease virus-induced encephalitis. Sequencing revealed a 100% homology of the isolated Aujeszky disease virus with Aujeszky disease virus isolates of wild boar from Eastern Germany.

Prenatal brain imaging in congenital toxoplasmosis

OBJECTIVE

To describe brain imaging findings and outcomes in fetuses with confirmed congenital toxoplasmosis (CTX).

METHODS

Physicians from Prenatal Diagnosis Units in ten Latin American countries were contacted and asked to provide data on fetuses with ultrasound findings suggestive of intrauterine infection and a positive diagnosis of CTX. The imaging studies were reviewed, and findings were described and tabulated.

RESULTS

Intracranial findings suggestive of CTX were identified in eight patients at a median gestational age of 31.5 weeks (range, 24.4-34 weeks). Ventriculomegaly was found in seven patients [severe (3), mild (4)]. Multiple echogenic nodular foci consistent with calcifications were found in seven patients [brain parenchyma (7), periventricular zone (3) and caudothalamic zone (3)]. Diffuse periventricular echogenicity or cysts were seen in three and callosal dysgenesis in one. All six survivors have choroidoretinitis and intracranial calcifications, four suffer from developmental delay and three of these four children also suffer from seizures and blindness. Postnatal hydrocephaly was found in five children.

CONCLUSIONS

Ventriculomegaly associated with multiple echo-dense nodules is characteristic of severe fetal toxoplasmosis and carries a poor prognosis. When the ventricles have normal size or are only mildly dilated, the nodules restricted to the parenchyma development may be normal.

Long-acting insulin analogues elicit atypical signalling events mediated by the insulin receptor and insulin-like growth factor-I receptor

AIMS/HYPOTHESIS

Insulin analogues were developed to improve the pharmacological properties of injected insulin and to better mimic endogenous insulin output. However, certain insulin analogues have been suggested to display IGF-I-like biological activities. Furthermore, several recent epidemiological studies have suggested a potential increase in cancer risk for treatment of diabetes patients with long-acting analogue insulin glargine (A21Gly,B31Arg,B32Arg human insulin). Additional studies, however, reported no increased cancer risk. The purpose of the present study was to identify the receptor(s) and signal transduction pathways responsible for the biological actions of insulin glargine and insulin detemir (B29Lys[ε-tetradecanoyl],desB30 human insulin).

METHODS

The colon cancer-derived cell line HCT116 was treated with increasing doses of insulin glargine, insulin detemir, regular insulin or IGF-I, and receptor activation was evaluated by immunoprecipitation assays. IGF-I receptor (IGF-IR) internalisation following insulin glargine treatment was assessed by confocal microscopy. Activation of the Akt and extracellular signal-regulated kinase pathways was evaluated by western blots. The anti-apoptotic effect of the analogues was measured by poly-(ADP ribose) polymerase antibody and annexin assays.

RESULTS

We found evidence for dual activation of the insulin receptor and IGF-IR by the analogues. Dose-dependency experiments showed that insulin glargine was able to phosphorylate the IGF-IR at fivefold lower doses than those required to activate the insulin receptor. We also showed that insulin glargine can lead to prolonged activation of the receptors and therefore promote abnormal signalling. Confocal imaging experiments showed that insulin glargine, but not regular insulin induced IGF-IR internalisation similarly to IGF-I. Finally, both analogues displayed IGF-I-like anti-apoptotic activities and stimulated cell cycle progression.

CONCLUSIONS/INTERPRETATION

Our data indicate that insulin glargine and insulin detemir display atypical signalling activities that differ from those elicited by regular insulin and involve activation of the anti-apoptotic IGF-IR.

Additive manufacturing models of fetuses built from three-dimensional ultrasound, magnetic resonance imaging and computed tomography scan data

OBJECTIVE

To generate physical fetal models using images obtained by three-dimensional ultrasonography (3DUS), magnetic resonance imaging (MRI) and computed tomography (CT) to guide additive manufacturing technology.

METHODS

Images from 33 fetuses, including three sets of twins, were used. Fifteen fetuses were normal and evaluated only by 3DUS. Eighteen cases had abnormalities such as conjoined twins, tumors, aneuploidy, skeletal abnormalities, central nervous system abnormalities and facial or thoracic defects. Scans were performed using high-resolution 3DUS. In cases of abnormalities, MRI and CT were performed on the same day as 3DUS. The images obtained with 3DUS, CT or MRI were exported to a workstation in DICOM format. A single observer performed slice-by-slice manual segmentation using a digital high-definition screen. Software that converts medical images into numerical models was used to construct virtual 3D models, which were physically realized using additive manufacturing technologies.

RESULTS

Physical models based on 3DUS, MRI and CT images either separately or combined were successfully generated. They were remarkably similar to the postnatal appearance of the aborted fetus or newborn baby, especially in cases with pathology.

CONCLUSION

The use of 3DUS, MRI and CT may improve our understanding of fetal anatomical characteristics, and these technologies can be used for educational purposes and as a method for parents to visualize their unborn baby. The images can be segmented and applied separately or combined to construct 3D virtual and physical models.

Enhanced ozone strongly reduces carbon sink strength of adult beech (Fagus sylvatica)--resume from the free-air fumigation study at Kranzberg Forest

Ground-level ozone (O(3)) has gained awareness as an agent of climate change. In this respect, key results are comprehended from a unique 8-year free-air O(3)-fumigation experiment, conducted on adult beech (Fagus sylvatica) at Kranzberg Forest (Germany). A novel canopy O(3) exposure methodology was employed that allowed whole-tree assessment in situ under twice-ambient O(3) levels. Elevated O(3) significantly weakened the C sink strength of the tree-soil system as evidenced by lowered photosynthesis and 44% reduction in whole-stem growth, but increased soil respiration. Associated effects in leaves and roots at the gene, cell and organ level varied from year to year, with drought being a crucial determinant of O(3) responsiveness. Regarding adult individuals of a late-successional tree species, empirical proof is provided first time in relation to recent modelling predictions that enhanced ground-level O(3) can substantially mitigate the C sequestration of forests in view of climate change.

[Stifle stability after lateral suture stabilisation using Ethibond Excel®: early destabilisation following cyclic passive joint motion]

OBJECTIVE

1) To report cranio-caudal stifle stability (ccStab) following lateral suture stabilisation (LSS) and passive joint motion. 2) To report tension within the suture following knotting.

MATERIAL AND METHODS

ccStab was measured in vitro on latero-medial radiographs in 10 stifles of orthopaedically sound dogs (> 20 kg BW). ccStab was assessed in the intact joint, after transection of the cranial cruciate ligament and following LSS using a multi strand Ethibond loop and clamped square knots, as well as after 50, 100, 250 and 350 cycles of passive joint motion. Tension within seven suture loops was measured using a material testing machine. Tension was measured after the first (FMax) and last knot (FEnd).

RESULTS

ccStab following LSS was 3.7 mm und was greater by 2.7 mm than with intact cruciate ligament. Already 250 passive cycles of passive joint motion induced significant destabilisation by 1.5 mm. FMax was 133 N und dropped to 6 N (FEnd) after completion of the last knot.

CONCLUSION

LSS using Ethibond and clamped square knots do not allow for restoration of physiological stifle stability. Already few cycles of passive joint motion further destabilise the joint. One of the reasons for these disappointing results is the method of suture fixation as clamped square knots did not allow for conservation of initial loop tension.

CLINICAL RELEVANCE

LSS using a multi strand Ethibond loop and clamped square knots should be avoided.