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Over the last 80 years, a series of critical events has led to reconsideration of the basic premises of medical ethics. One of these events was the recognition of horrific medical experiments performed by German medical scientists in World War II concentration camps, resulting in intensified emphasis on a consent requirement, later understood as grounded in the bioethical principle of respect for autonomy, as well as on the moral accountability of the experimenter. Another important event that is forcing a reconsideration of respect for autonomy in medicine and health care is the COVID-19 pandemic. But this time the matter pulls in a different direction, from respect for autonomy to social responsibility, represented in problems as disparate as the wearing of masks, vaccination requirements, and equity in vaccine access and distribution. How can modern bioethics, in part a creature of the response to Nazi crimes, accommodate the intensified sensitivity about public health needs that has accompanied the shock of the pandemic? The responses of European medical ethics to the Nazi era provide tools for bioethics as it faces the challenge now at hand. This article uses historical context from postwar Europe to argue that, in light of the pandemic experience, respect for autonomy must systematically incorporate a commitment to social responsibility.

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Surveying the early responses to the Covid-19 pandemic among nation states, one finds a veritable babel of responses, some predictable and some not. Would these results have been different half a century or more ago, when smallpox was eradicated and hopes were high that international cooperation would yield similar results for other infectious diseases? Is this a story about the stability provided by the bipolar postwar world, juxtaposed with the complex geopolitical repositioning that finally followed the collapse of the Soviet Union, or is that too rich an irony? A multipolar world may indeed be less prepared to cope with an international health crisis than a bipolar one. In any case, the patterns of global response are not only reminiscent of the Cold War era itself but also suggestive of a new vaccination cold war.

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Part I provides the historiographical context and examines the causes which led to the creation of the first independent research ethics committee (REC) at Porton Down, Britain's biological and chemical warfare establishment, in operation since the First World War. The papers in part I and part II argue that the introduction of RECs in the UK stemmed from concerns about legal liability and research ethics among scientists responsible for human experiments, and from the desire of the UK military medical establishment to create an external organisation which would function both as an ' internal space ' for ethical debate and as an ' external body ' to share moral and legal responsibility. The paper asks: What factors were responsible for causing military scientists and government officials to contemplate the introduction of formalised structures for ethical review within the UK military? It argues that Porton may have been exempt from public scrutiny, but it was not above the law of the land. By the mid-1960s evidence of serious ill effects among staff members and service personnel involved in tests could no longer be ignored. Whereas the security of the British realm had previously trumped almost any other argument in contentious debates about chemical warfare, the role of medical ethics suddenly moved to the forefront of Porton's deliberations, so much so that tests with incapacitants were temporarily suspended in 1965. It was this crisis, examined in detail in part II, which functioned as a catalyst for the creation of the Applied Biology Committee as the responsible body, and first point of call, for authorising human experiments at Porton Down.

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Using a major ethics crisis as a methodological approach to study secret science environments, part II examines the origins and organisation of the Applied Biology Committee (ABC), the first independent research ethics committee (REC) at Porton Down, Britain's biological and chemical warfare establishment since the First World War. Although working in great secrecy, the UK military, and Porton in particular, did not operate in a social, political and legal vacuum. Paradigm shifts in civilian medical ethics, or public controversy about atomic, chemical and biological weapons, could thus influence Porton's self-perception and the conduct of its research. The paper argues that the creation of the first REC at Porton in 1965, that is, the ABC, as the ' father confessor ' inside the UK's military research establishment reflected a broader paradigm shift in the field of human research ethics in the mid-1960s.

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OBJECTIVES: To investigate whether (1) the type of fixation at the shaft (hybrid vs. locking), (2) the position of the plate (offset vs. contact) and (3) the implant material has a significant effect on (a) construct stiffness and (b) fatigue life in a distal femur extraarticular comminuted fracture model using the same design of distal femur periarticular locking plate. METHODS: An extraarticular severely comminuted distal femoral fracture pattern (OTA/AO 33-A3) was simulated using artificial bone substitutes. Ten-hole distal lateral femur locking plates were used for fixation per the recommended surgical technique. At the distal metaphyseal fragment, all possible locking screws were placed. For the proximal diaphyseal fragment, different types of screws were used to create 4 different fixation constructs: (1) stainless steel hybrid (SSH), (2) stainless steel locked (SSL), (3) titanium locked (TiL), and (4) stainless steel locked with 5-mm offset at the diaphysis (SSLO). Six specimens of each construct configuration were tested. First, each specimen was nondestructively loaded axially to determine the stiffness. Then, each specimen was cyclically loaded with increasing load levels until failure. RESULTS: Construct Stiffness: The fixation construct with a stainless steel plate and hybrid fixation (SSH) had the highest stiffness followed by the construct with a stainless steel plate and locking screws (SSL) and were not statistically different from each other. Offset placement (SSLO) and using a titanium implant (TiL) significantly reduced construct stiffness. Fatigue Failure: The stainless steel with hybrid fixation group (SSH) withstood the most number of cycles to failure and higher loads, followed by the stainless steel plate and locking screw group (SSL), stainless steel plate with locking screws and offset group (SSLO), and the titanium plate and locking screws group (TiL) consecutively. Offset placement (SSLO) as well as using a titanium implant (TiL) reduced cycles to failure. CONCLUSIONS: Using the same plate design, the study showed that implant material, screw type, and position of the plate affect the construct stiffness and fatigue life of the fixation construct. With this knowledge, the surgeon can decide the optimal construct based on a given fracture pattern, bone strength, and reduction quality.

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BACKGROUND: Construct stiffness affects healing of bones fixed with locking plates. However, variable construct stiffness reported in the literature may be attributable to differing test configurations and direct comparisons may clarify these differences. QUESTIONS/PURPOSES: We therefore asked whether different distal femur locking plate systems and constructs will lead to different (1) axial and rotational stiffness and (2) fatigue under cyclic loading. METHODS: We investigated four plate systems for distal femur fixation (AxSOS, LCP, PERI-LOC, POLYAX) of differing designs and materials using bone substitutes in a distal femur fracture model (OTA/AO 33-A3). We created six constructs of each of the four plating systems. Stiffness under static and cyclic loading and fatigue under cyclic loading were measured. RESULTS: Mean construct stiffness under axial loading was highest for AxSOS (100.8 N/mm) followed by PERI-LOC (80.8 N/mm) and LCP (62.6 N/mm). POLYAX construct stiffness testing showed the lowest stiffness (51.7 N/mm) with 50% stiffness of AxSOS construct testing. Mean construct stiffness under torsional loading was similar in the group of AxSOS and PERI-LOC (3.40 Nm/degree versus 3.15 Nm/degree) and in the group of LCP and POLYAX (2.63 Nm/degree versus 2.56 Nm/degree). The fourth load level of > 75,000 cycles was reached by three of six AxSOS, three of six POLYAX, and two of six PERI-LOC constructs. All others including all LCP constructs failed earlier. CONCLUSIONS: Implant design and material of new-generation distal femur locking plate systems leads to a wide range of differences in construct stiffness. CLINICAL RELEVANCE: Assuming construct stiffness affects fracture healing, these data may influence surgical decision-making in choosing an implant system.

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The paper provides a critical commentary on the article by Baker and McCullough on Medical Ethic's Appropriation of Moral Philosophy. The author argues that Baker and McCullough offer a more "pragmatic" approach to the history of medical ethics that has the potential to enrich the bioethics field with a greater historical grounding and sound methodology. Their approach can help us to come to a more nuanced understanding about the way in which medical ethics has connected, disconnected, and reconnected with philosophical ideas throughout the centuries. The author points out that Baker and McCullough's model can run the danger of overemphasizing the role of medical ethicists whilst marginalizing the influence of philosophers and of other historical actors and forces. He critically reviews the two case studies on which Baker and McCullough focus and concludes that scholars need to bear in mind the levels of uncertainty and ambivalence that accompany the process of transformation and dissemination of moral values in medicine and medical practice.

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Three different anterior plate-fixation systems are available for the stabilisation of the cervical spine: (1) the cervical spine locking plate (CSLP), (2) dynamic plates allowing vertical migration of the fixation screws, and (3) various types of plates that are secured with either monocortical or bicortical unlocked screws. Unicortical screw purchase does not involve the risk of posterior cortex penetration and possible injuries to the spinal cord. The development of locking plates with unicortical screw-fixation and intrinsic stability of the screw-plate interface, via an angle-stabilised connection, was an attempt to increase the stability of unicortical screw-fixation systems. The aim of the study was to compare the biomechanical properties of a non-locking, anterior-plate system with 4.5 mm screw fixation and a locking anterior-plate system, in a single destabilised cervical spine-motion segment. Using fresh cadaveric cervical spine specimen C3-C7, multidirectional flexibility was measured at the C4-C5 level in an unconstrained test system, before and after destabilisation and fixation with an anterior plate with either locked or unlocked screw purchase. Direct comparison of the fixed cervical spine segments with unlocked and locked anterior-plate fixation did not demonstrate significant differences. This in vitro study documented that neither locked nor unlocked anterior-plate fixation can increase stability in all modes of testing. H-plate spondylodesis with unlocked screws seems to provide sufficient mechanical integrity in most cases of monosegmental lesions.

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Injury cause, treatment, and long-term results [American Orthopaedic Foot and Ankle Society (AOFAS) Midfoot Score, Hannover Scoring System, Hannover Outcome Questionnaire] of patients with Chopart joint dislocations or fracture-dislocations were evaluated. Between 1972 and 1997, 100 patients with 110 Chopart joint dislocations were treated in the authors' institution. Pure Chopart joint dislocations were observed in 28 (25%) feet, fracture-dislocations in 60 (55%) feet, and combined Chopart-Lisfranc joint fracture-dislocations in 22 (20%) feet. The primary treatment was operative in 91 (83%) feet and nonoperative in 19 (17%) feet. Sixty-five (65%) patients had follow-up after an average of 9 years (range, 2-25 years). The mean scores of the entire follow-up group were: AOFAS score, 75 points; Hannover Scoring System, 69 points (maximium possible score = 100 points); Hannover Outcome Questionnaire, 68 points (maximium possible score = 100 points). There were no differences between the scores for pure dislocations or fracture-dislocations of the Chopart joint, but significantly lower scores were noted with combined Chopart-Lisfranc joint fracture-dislocations. In all three injury pattern groups, an initial anatomic reduction was essential for good results. The high functional restrictions in Chopart dislocations can most likely be minimized with initial open reduction, especially in fracture-dislocations. A closed reduction yielded good results only with pure dislocations, when anatomic conditions could be restored, or if there were contraindications to surgery.

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Anterior plate fixation with unicortical screw purchase does not involve the risk of posterior cortex penetration and possible injuries of the spinal cord. However, there are very few biomechanical data about the immediate stability of non-locking plate fixation with unicortical or bicortical screw placement. The aim of the present study was to evaluate the immediate biomechanical properties in terms of flexibility of a non-locking anterior plate system with 4.5-mm screw fixation and unicortical or bicortical screw purchase applied to a single destabilized cervical spine motion segment. Using fresh cadaveric cervical spine specimens C3-C7, multidirectional flexibility was measured at the level C4-C5 before and after destabilization and fixation with an anterior plate with either unicortical or bicortical screw purchase. The results showed that fixed cervical spine segments with anterior plate and bicortical screw purchase were more rigid than intact specimens in all modes of testing. The difference was statistically significant for flexion and extension ( P<0.001). Plate fixation with unicortical screw purchase had statistically significant decreased ranges of motion compared to the intact specimen only in extension. Neither unicortical nor bicortical screw purchase decreased the range of motion significantly in axial rotation compared to the intact specimens. This in vitro study documented that neither unicortical nor bicortical screw purchase with non-locking plate fixation can increase stability in all modes of testing, in axial rotation in particular. Direct comparison between the group with uni- and that with bicortical screw fixation did not reveal significant differences, and therefore no advantage was shown for either type of screw fixation. Therefore, we demonstrated that both uni- and bicortical screw purchase with non-locking plate fixation can decrease immediate flexibility of the tested motion segment, with better results for bicortical purchase. No significant differences were found comparing the two groups of screw fixation. These data suggest that unicortical screw fixation can be used for anterior plate fixation with a comparable immediate stability to bicortical screw fixation.

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