Differences of tensile strength in knot tying technique between orthopaedic surgical instructors and trainees

Background Knot tying technique is an extremely important basic skill for all surgeons. Clinically, knot slippage or suture breakage will lead to wound complications. Although some previous studies described the knot-tying technique of medical students or trainees, little information had been reported on the knot-tying technique of instructors. The objective of the preset study was to assess surgeons’ manual knot tying techniques and to investigate the differences of tensile strength in knot tying technique between surgical instructors and trainees. Methods A total of 48 orthopaedic surgeons (postgraduate year: PGY 2–18) participated. Surgeons were requested to tie surgical knots manually using same suture material. They were divided into two groups based on each career; instructors and trainees. Although four open conventional knots with four throws were chosen and done with self-selected methods, knot tying practice to have the appropriate square knots was done as education only for trainees before the actual trial. The knots were placed over a 30 cm long custom made smooth polished surface with two cylindrical rods. All knots were tested for tensile strength using a tensiometer. The surgical loops were loaded until the knot slipped or the suture broke. The tensile strength of each individual knot was defined as the force (N) required to result in knot failure. Simultaneously, knot failure was evaluated based on knot slippage or suture rupture. In terms of tensile strength or knot failure, statistical comparison was performed between groups using two-tailed Mann–Whitney U test or Fisher exact probability test, respectively. Results Twenty-four instructors (PGY6–PGY18) and 24 trainees (PGY2–PGY5) were enrolled. Tensile strength was significantly greater in trainees (83.0 ± 27.7 N) than in instructors (49.9 ± 34.4 N, P = 0.0246). The ratio of slippage was significantly larger in instructors than in trainees (P < 0.001). Knot slippage (31.8 ± 17.7 N) was significantly worse than suture rupture (89.9 ± 22.2 N, P < 0.001) in tensile strength. Conclusions Mean tensile strength of knots done by trainees after practice was judged to be greater than that done by instructors in the present study. Clinically, knot slippage can lead to wound dehiscence, compared to suture rupture.

Differences of tensile strength in knot tying technique between orthopaedic surgical instructors and trainees

Background: Knot tying technique is an extremely important basic skill for all surgeons. Clinically, knot slippage or suture breakage will lead to wound complications. Although some previous studies described the knot-tying technique of medical students or trainees, little information had been reported on the knot-tying technique of instructors. The objective of the preset study was to assess surgeons’ manual knot tying techniques and to investigate the differences of tensile strength in knot tying technique between surgical instructors and trainees.Methods: A total of 48 orthopaedic surgeons (postgraduate year: PGY 2-18) participated. Surgeons were requested to tie surgical knots manually using same suture material. They were divided into two groups based on each career; instructors and trainees. Although 4 open conventional knots with 4 throws were chosen and done with self-selected methods, knot tying practice to have the appropriate square knots was done as education only for trainees before the actual trial. The knots were placed over a 30 cm long custom made smooth polished surface with 2 cylindrical rods. All knots were tested for tensile strength using a tensiometer. The surgical loops were loaded until the knot slipped or the suture broke. The tensile strength of each individual knot was defined as the force (N) required to result in knot failure. Simultaneously, knot failure was evaluated based on knot slippage or suture rupture. In terms of tensile strength or knot failure, statistical comparison was performed between groups using two-tailed Mann-Whitney U test or Fisher exact probability test, respectively.Results: Twenty-four instructors (PGY6- PGY18) and 24 trainees (PGY2-PGY5) were enrolled. Tensile strength was significantly greater in trainees (83.0 ± 27.7N) than in instructors (49.9 ± 34.4N, P=0.0246). The ratio of slippage was significantly larger in instructors than in trainees (P<0.001). Knot slippage (31.8 ± 17.7N) was significantly worse than suture rupture (89.9 ± 22.2N, P<0.001) in tensile strength.Conclusions: Mean tensile strength of knots done by trainees after practice was judged to be greater than that done by instructors in the present study. Clinically, knot slippage can lead to wound dehiscence, compared to suture rupture.

Differences of tensile strength in knot tying technique between orthopaedic surgical instructors and trainees

Background: Knot tying technique is an extremely important basic skill for all surgeons. Clinically, knot slippage or suture breakage will lead to wound complications. Although some previous studies described the knot-tying technique of medical students or trainees, little information had been reported on the knot-tying technique of instructors. The objective of the preset study was to assess surgeons’ manual knot tying techniques and to investigate the differences of tensile strength in knot tying technique between surgical instructors and trainees. Methods: A total of 48 orthopaedic surgeons (postgraduate year: PGY 2-18) participated. Surgeons were requested to tie surgical knots manually using same suture material. They were divided into two groups based on each career; instructors and trainees. Although 4 open conventional knots with 4 throws were chosen and done with self-selected methods, knot tying practice to have the appropriate square knots was done as education only for trainees before the actual trial. The knots were placed over a 30 cm long custom made smooth polished surface with 2 cylindrical rods. All knots were tested for tensile strength using a tensiometer. The surgical loops were loaded until the knot slipped or the suture broke. The tensile strength of each individual knot was defined as the force (N) required to result in knot failure. Simultaneously, knot failure was evaluated based on knot slippage or suture rupture. In terms of tensile strength or knot failure, statistical comparison was performed between groups using two-tailed Mann-Whitney U test or Fisher exact probability test, respectively. Results: Twenty-four instructors (PGY6- PGY18) and 24 trainees (PGY2-PGY5) were enrolled. Tensile strength was significantly greater in trainees (83.0 ± 27.7N) than in instructors (49.9 ± 34.4N, P=0.0246). The ratio of slippage was significantly larger in instructors than in trainees (P<0.001). Knot slippage (31.8 ± 17.7N) was significantly worse than suture rupture (89.9 ± 22.2N, P<0.001) in tensile strength. Conclusions: Mean tensile strength of knots done by trainees after practice was judged to be greater than that done by instructors in the present study. Clinically, knot slippage can lead to wound dehiscence, compared to suture rupture.

Differences of tensile strength in knot tying technique between orthopaedic surgical instructors and trainees

Background: Knot tying technique is an extremely important basic skill for all surgeons. Clinically, knot slippage or suture breakage will lead to wound complications. Although some previous studies described the knot-tying technique of medical students or trainees, little information had been reported on the knot-tying technique of instructors. The objective of the preset study was to assess surgeons’ manual knot tying techniques and to investigate the differences of tensile strength in knot tying technique between surgical instructors and trainees.Methods: A total of 48 orthopaedic surgeons (postgraduate year: PGY 2-18) participated. Surgeons were requested to tie surgical knots manually using same suture material. They were divided into two groups based on each career; instructors and trainees. Although 4 open conventional knots with 4 throws were chosen and done with self-selected methods, knot tying practice to have the appropriate square knots was done as education only for trainees before the actual trial. The knots were placed over a 30 cm long custom made smooth polished surface with 2 cylindrical rods. All knots were tested for tensile strength using a tensiometer. The surgical loops were loaded until the knot slipped or the suture broke. The tensile strength of each individual knot was defined as the force (N) required to result in knot failure. Simultaneously, knot failure was evaluated based on knot slippage or suture rupture. In terms of tensile strength or knot failure, statistical comparison was performed between groups using two-tailed Mann-Whitney U test or Fisher exact probability test, respectively.Results: Twenty-four instructors (PGY6- PGY18) and 24 trainees (PGY2-PGY5) were enrolled. Tensile strength was significantly greater in trainees (83.0 ± 27.7N) than in instructors (49.9 ± 34.4N, P=0.0246). The ratio of slippage was significantly larger in instructors than in trainees (P<0.001). Knot slippage (31.8 ± 17.7N) was significantly worse than suture rupture (89.9 ± 22.2N, P<0.001) in tensile strength.Conclusions: Mean tensile strength of knots done by trainees after practice was judged to be greater than that done by instructors in the present study. Clinically, knot slippage can lead to wound dehiscence, compared to suture rupture.

Differences of tensile strength in knot tying technique between orthopaedic surgical instructors and trainees

Background: Knot tying technique is an extremely important basic skill for all surgeons. Clinically, knot slippage or suture breakage will lead to wound complications. Although some previous studies described the knot-tying technique of medical students or trainees, little information had been reported on the knot-tying technique of instructors. The objective of the preset study was to assess surgeons’ manual knot tying techniques and to investigate the differences of tensile strength in knot tying technique between surgical instructors and trainees.Methods: A total of 48 orthopaedic surgeons (postgraduate year: PGY 2-18) participated. Surgeons were requested to tie surgical knots using same suture material. They were divided into two groups based on each career; instructors and trainees. Although 4 knots with 4 throws were chosen and done with self-selected methods, knot tying practice was done as education only for trainees before the actual trial. The knots were placed over a 30 cm long custom made smooth polished surface with 2 cylindrical rods. All knots were tested for tensile strength using a tensiometer. The surgical loops were loaded until the knot slipped or the suture broke. The tensile strength of each individual knot was defined as the force (N) required to result in knot failure. Simultaneously, knot failure was evaluated based on knot slippage or suture rupture. In terms of tensile strength or knot failure, statistical comparison was performed between groups using two-tailed Mann-Whitney U test or Fisher exact probability test, respectively.Results: Twenty-four instructors (PGY6- PGY18) and 24 trainees (PGY2-PGY5) were enrolled. Tensile strength was significantly greater in trainees (83.0 ± 27.7N) than in instructors (49.9 ± 34.4N, P=0.0246). The ratio of slippage was significantly larger in instructors than in trainees (P<0.001). Knot slippage (31.8 ± 17.7N) was significantly worse than suture rupture (89.9 ± 22.2N, P<0.001) in tensile strength.Conclusions: Mean tensile strength of knots done by trainees after practice was judged to be greater than that done by instructors in the present study. Clinically, knot slippage can lead to wound dehiscence, compared to suture rupture.

1. Life

‘Life’ explains that virtually nothing is known about the first half of Socrates’ life, but details of his later life, with his wife Xanthippe and his sons, are provided. Socrates was seen as an arguer and questioner, who went about challenging people’s pretensions to expertise and revealing inconsistencies in their beliefs, but also as a religious deviant and a subverter of traditional religion and morality. In 400 or 399 he was accused of not recognizing the gods of the city, introducing new gods, and corrupting the young—a charge that probably had a political dimension. He was sentenced to death. Though there is no record of the actual trial, accounts were provided by Plato and Xenophon.

Innovative exploration of safe in-flightcrew escape options

Purpose The purpose of this paper is to explore various in-flight crew escape options of a prototype transport aircraft and finalize the option offering safest crew egress for different combinations of contingencies and flight conditions. Design/methodology/approach Various egress options were explored through simulation in a computational fluid dynamics (CFD) software using aircraft 3D CAD model and scalable digital mannequins. For this, certain important contingencies which best describe the extreme aircraft behaviour were identified. Crew escape options, which have least external interference in expected egress trajectory, were selected. Several test simulations representing each feasible combination of contingency, escape option and flight condition were simulated. The option which offers safe crew escape in each test case is deemed to be the safest egress option for the test aircraft. Findings Among five options explored, crew escape through forward ventral hatch provided the safest crew escape for all test cases. The selected option was validated for robustness with additional test cases modelling different anthropometric characteristics of 5th and 50th percentile pilot populations with different postures. Originality/value In-flight validation of safe crew escape option is infeasible by actual trial. Exploration of safe crew options for required number of test cases by any analytical method or by wind tunnels tests is tedious, time consuming and extremely expensive. On the other hand, exploration of safest crew option by CFD, besides being first of its kind, provides convenient option to configure, test and validate different test cases with unmatched benefits in time, cost and simplicity.

Was war die Lateransynode von 649? Was sollte sie sein?

The radical nature of the Lateran Synod of 649 – which anathematized three patriarchs from Constantinople, one from Alexandria, two imperial laws, and one bishop identified as the heresiarch – was unprecedented in the history of the church. Hence the Synod represents the high point of the Monothelete controversy. This article analyzes its acts in order to identify the kind of synod which the Lateran gathering understood itself to be, thereby demonstrating that this papal synod, the most important of the early middle ages, constituted itself as a court of justice and pretended to go through a so-called synodal accusatory legal process. Patterning their proceedings after the example of the fifth-century lawsuit against Eutyches, Nestorius and Dioscorus, the gathering claimed to be following, in a canonically faithful manner, the standing synodal legal procedure according to the church’s statues. However, the examination of the actual trial reveals serious breaches of legal procedure. The mandatory summons of the accused was omitted, thereby taking away any possibility of their defense. Moreover, the absolute separation of prosecutor and judge was undermined and, because they were written beforehand, not only the record of the process but also its judgement were a farce. Relying on a theology of Roman primacy, the synod posited a Roman competence which challenged the actual authority of an ecumenical council convened by the emperor. In this respect, here is the first early medieval attempt to replace the institution of the ecumenical council with a papally led Concilium universale. Conceptionally organized by Maximus the Confessor with Popes Theodorus I and Martin I, and staged as a literary product by him and his students, the Lateran Synod was, according to canonical and imperial law, an illegal event which rendered any agreement in the theological controversy impossible.

Discrepancies between ClinicalTrials.gov recruitment status and actual trial status: a cross-sectional analysis

ObjectivesTo determine the accuracy of the recruitment status listed on ClinicalTrials.gov as compared with the actual trial status.DesignCross-sectional analysis.SettingRandom sample of interventional phase 2–4 clinical trials registered between 2010 and 2012 on ClinicalTrials.gov.Primary outcome measureFor each trial which was listed within ClinicalTrials.gov as ongoing, two investigators performed a comprehensive literature search for evidence that the trial had actually been completed. For each trial listed as completed or terminated early by ClinicalTrials.gov, we compared the date that the trial was actually concluded with the date the registry was updated to reflect the study’s conclusion status.ResultsAmong the 405 included trials, 92 had a registry status indicating that study activity was either ongoing or the recruitment status was unknown. Of these, published results were available for 34 (37%). Among the 313 concluded trials, the median delay between study completion and a registry update reflecting that the study had ended was 141 days (IQR 48–419), with delays of over 1 year present for 29%. In total, 125 trials (31%) either had a listed recruitment status which was incorrect or had a delay of more than 1 year between the time the study was concluded and the time the registry recruitment status was updated.ConclusionsAt present, registry recruitment status information in ClinicalTrials.gov is often outdated or wrong. This inaccuracy has implications for the ability of researchers to identify completed trials and accurately characterise all available medical knowledge on a given subject.

Plato’s Philosophical Politics

This paper suggests an alternative account of the political character of Plato’s political philosophy. After pointing toward some problems of the common developmental paradigm, which emphasizes discontinuities between Plato’s Socratic early writings, the mature utopianism of the Republic, and the late pessimism of the Laws, it proposes that Plato’s two large constructive works, the Republic and Laws, are related to two actual historical events in which Plato played a role, the trial of Socrates and Plato’s failed intervention in Sicilian politics. On this view, the Republic is to the Apology of Socrates as the Laws is to the Seventh Letter. The Republic is an imaginative reconstruction of the sort of defense of philosophy under more favorable conditions than obtained in the actual trial; the Laws is an imaginative reconstruction of the sort of political reform that Plato advocated under more favorable conditions than obtained in Syracuse under Dionysius II. The paper suggests this as the basis of a unified interpretation of Plato’s political philosophy.