Exploring the uncertainties of early detection results: model-based interpretation of mayo lung project

Background: The Mayo Lung Project (MLP), a randomized controlled clinical trial of lung cancer screening conducted between 1971 and 1986 among male smokers aged 45 or above, demonstrated an increase in lung cancer survival since the time of diagnosis, but no reduction in lung cancer mortality. Whether this result necessarily indicates a lack of mortality benefit for screening remains controversial. A number of hypotheses have been proposed to explain the observed outcome, including over-diagnosis, screening sensitivity, and population heterogeneity (initial difference in lung cancer risks between the two trial arms). This study is intended to provide model-based testing for some of these important arguments.Method: Using a micro-simulation model, the MISCAN-lung model, we explore the possible influence of screening sensitivity, systematic error, over-diagnosis and population heterogeneity.Results: Calibrating screening sensitivity, systematic error, or over-diagnosis does not noticeably improve the fit of the model, whereas calibrating population heterogeneity helps the model predict lung cancer incidence better.Conclusions: Our conclusion is that the hypothesized imperfection in screening sensitivity, systematic error, and over-diagnosis do not in themselves explain the observed trial results. Model fit improvement achieved by accounting for population heterogeneity suggests a higher risk of cancer incidence in the intervention group as compared with the control group

Bone grafts and bone substitutes for treating distal radial fractures in adults

BACKGROUND: Surgical treatment of fractures of the distal radius can involve the implantation of bone scaffolding materials (bone grafts and substitutes) into bony defects that frequently arise after fracture reduction. OBJECTIVES: To review the evidence from randomised controlled trials evaluating the implanting of bone scaffolding materials for treating distal radial fractures in adults. SEARCH METHODS: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (June 2007), the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and other databases, conference proceedings and reference lists. No language restrictions were applied. SELECTION CRITERIA: Randomised or quasi‐randomised controlled clinical trials evaluating the use of bone scaffolding for treating distal radial fracture in adults. DATA COLLECTION AND ANALYSIS: Two people independently selected studies and undertook assessment and data collection. MAIN RESULTS: Ten heterogenous trials involving 874 adults with generally unstable fractures were grouped into six comparisons. No trial had proven allocation concealment. Four trials (239 participants) found implantation of bone scaffolding (autogenous bone graft (one trial); Norian SRS ‐ a bone substitute (two trials); methylmethacrylate cement (one trial)) improved anatomical outcomes compared with plaster cast alone; and two found it improved function. Reported complications of bone scaffolding were transient discomfort resulting from extraosseous deposits of Norian SRS; with surgical removal of one intra‐articular deposit. One trial (323 participants) comparing bone substitute (Norian SRS) versus plaster cast or external fixation found no difference in functional or anatomical outcomes at one year. Statistically significant complications in the respective groups were extraosseous Norian SRS deposits and pin track infection. One trial (48 participants with external fixation) found that autogenous bone graft did not significantly change outcome. There was one serious donor‐site complication. One trial (21 participants) found some indication of worse outcomes for hydroxyapatite bone cement compared with Kapandji's intrafocal pinning. Three trials (180 participants) found bone scaffolding (autogenous bone graft (one trial); Norian SRS (one trial); methylmethacrylate cement (one trial)) gave no significant difference in functional outcomes but some indication of better anatomical outcomes compared with external fixation. Most reported complications were associated with external fixation; extraosseous deposits of Norian SRS occurred in one trial. One trial (93 participants with dorsal plate fixation) found autografts slightly improved wrist function compared with allogenic bone material but with an excess of donor site complications. AUTHORS' CONCLUSIONS: Bone scaffolding may improve anatomical outcome compared with plaster cast alone but there is insufficient evidence to conclude on functional outcome and safety; or for other comparisons

New forming method of manufacturing cylindrical parts with nano/ultrafine grained structures by power spinning based on small plastic strains

A new spinning method to manufacture the cylindrical parts with nano/ultrafine grained structures is proposed, which consists of quenching, power spinning and recrystallization annealing. The microstructural evolution during the different process stages and macroforming quality of the spun parts made of ASTM 1020 steel are investigated. The results show that the microstructures of the ferrites and pearlites in the ASTM 1020 steel are transformed to the lath martensites after quenching. The martensite laths obtained by quenching are refined to 87 nm and a small amount of nanoscale deformation twins with an average thickness of 20 nm is generated after performing a 3-pass stagger spinning with 55% thinning ratio of wall thickness, where the equivalent strain required is only 0.92. The equiaxial ferritic grains with an average size of 160 nm and nano-carbides are generated by subsequent recrystallization annealing at 480°C for 30 min. The spun parts with high dimensional precision and low surface roughness are obtained by the forming method developed in this work, combining quenching with 3-pass stagger spinning and recrystallization annealing

Rehabilitation for distal radial fractures in adults

BACKGROUND: Fracture of the distal radius is a common clinical problem, particularly in older people with osteoporosis. There is considerable variation in the management, including rehabilitation, of these fractures. This is an update of a Cochrane review first published in 2002 and last updated in 2006. OBJECTIVES: To examine the effects of rehabilitation interventions in adults with conservatively or surgically treated distal radial fractures. SEARCH METHODS: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2014; Issue 12), MEDLINE, EMBASE, CINAHL, AMED, PEDro, OTseeker and other databases, trial registers, conference proceedings and reference lists of articles. We did not apply any language restrictions. The date of the last search was 12 January 2015. SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi‐RCTs evaluating rehabilitation as part of the management of fractures of the distal radius sustained by adults. Rehabilitation interventions such as active and passive mobilisation exercises, and training for activities of daily living, could be used on their own or in combination, and be applied in various ways by various clinicians. DATA COLLECTION AND ANALYSIS: The review authors independently screened and selected trials, and reviewed eligible trials. We contacted study authors for additional information. We did not pool data. MAIN RESULTS: We included 26 trials, involving 1269 mainly female and older patients. With few exceptions, these studies did not include people with serious fracture or treatment‐related complications, or older people with comorbidities and poor overall function that would have precluded trial participation or required more intensive treatment. Only four of the 23 comparisons covered by these 26 trials were evaluated by more than one trial. Participants of 15 trials were initially treated conservatively, involving plaster cast immobilisation. Initial treatment was surgery (external fixation or internal fixation) for all participants in five trials. Initial treatment was either surgery or plaster cast alone in six trials. Rehabilitation started during immobilisation in seven trials and after post‐immobilisation in the other 19 trials. As well as being small, the majority of the included trials had methodological shortcomings and were at high risk of bias, usually related to lack of blinding, that could affect the validity of their findings. Based on GRADE criteria for assessment quality, we rated the evidence for each of the 23 comparisons as either low or very low quality; both ratings indicate considerable uncertainty in the findings. For interventions started during immobilisation, there was very low quality evidence of improved hand function for hand therapy compared with instructions only at four days after plaster cast removal, with some beneficial effects continuing one month later (one trial, 17 participants). There was very low quality evidence of improved hand function in the short‐term, but not in the longer‐term (three months), for early occupational therapy (one trial, 40 participants), and of a lack of differences in outcome between supervised and unsupervised exercises (one trial, 96 participants). Four trials separately provided very low quality evidence of clinically marginal benefits of specific interventions applied in addition to standard care (therapist‐applied programme of digit mobilisation during external fixation (22 participants); pulsed electromagnetic field (PEMF) during cast immobilisation (60 participants); cyclic pneumatic soft tissue compression using an inflatable cuff placed under the plaster cast (19 participants); and cross‐education involving strength training of the non‐fractured hand during cast immobilisation with or without surgical repair (39 participants)). For interventions started post‐immobilisation, there was very low quality evidence from one study (47 participants) of improved function for a single session of physiotherapy, primarily advice and instructions for a home exercise programme, compared with 'no intervention' after cast removal. There was low quality evidence from four heterogeneous trials (30, 33, 66 and 75 participants) of a lack of clinically important differences in outcome in patients receiving routine physiotherapy or occupational therapy in addition to instructions for home exercises versus instructions for home exercises from a therapist. There was very low quality evidence of better short‐term hand function in participants given physiotherapy than in those given either instructions for home exercises by a surgeon (16 participants, one trial) or a progressive home exercise programme (20 participants, one trial). Both trials (46 and 76 participants) comparing physiotherapy or occupational therapy versus a progressive home exercise programme after volar plate fixation provided low quality evidence in favour of a structured programme of home exercises preceded by instructions or coaching. One trial (63 participants) provided very low quality evidence of a short‐term, but not persisting, benefit of accelerated compared with usual rehabilitation after volar plate fixation. For trials testing single interventions applied post‐immobilisation, there was very low quality evidence of no clinically significant differences in outcome in patients receiving passive mobilisation (69 participants, two trials), ice (83 participants, one trial), PEMF (83 participants, one trial), PEMF plus ice (39 participants, one trial), whirlpool immersion (24 participants, one trial), and dynamic extension splint for patients with wrist contracture (40 participants, one trial), compared with no intervention. This finding applied also to the trial (44 participants) comparing PEMF versus ice, and the trial (29 participants) comparing manual oedema mobilisation versus traditional oedema treatment. There was very low quality evidence from single trials of a short‐term benefit of continuous passive motion post‐external fixation (seven participants), intermittent pneumatic compression (31 participants) and ultrasound (38 participants). AUTHORS' CONCLUSIONS: The available evidence from RCTs is insufficient to establish the relative effectiveness of the various interventions used in the rehabilitation of adults with fractures of the distal radius. Further randomised trials are warranted. However, in order to optimise research effort and engender the large multicentre randomised trials that are required to inform practice, these should be preceded by research that aims to identify priority questions

Pre-operative pulmonary assessment for patients with hip fracture

Hip fracture is a common injury among the elderly. Although patients who receive hip fracture surgery carry the best functional recovery compared to other treatment modalities, the presence of postoperative pulmonary complications, such as atelectasis, pneumonia, and pulmonary thromboembolism, may contribute to increased length of hospital stay, perioperative morbidity, and mortality. This review aims to provide evidence-based recommendations for preoperative assessment and perioperative strategies to reduce the risk of pulmonary complications after hip fracture surgery. Clinical assessment and basic laboratory results are sufficient to stratify the risk of postoperative pulmonary complications. Well-documented risk factors for pulmonary complications include advanced age, poor general health status, current infections, pre-existing cardiopulmonary diseases, hypoalbuminemia, and impaired renal function. Apart from optimizing the patient's medical conditions, interventions such as lung expansion maneuvers and thromboprophylaxis have been proven to be effective in reducing the risk of pulmonary complications after hip fracture surgery