Adolescent displaced lateral-end clavicle fractures are not comparable to the adult variant. Epidemiology, fracture patterns and outcome of non-operative management.

Background: The primary aim of this study was to determine the epidemiology of lateral-end clavicle fractures in adolescents. The secondary aim was to assess the outcome following non-operative management. Methods: A retrospective review of all adolescent clavicle fractures over a 10-year period was undertaken. Fracture classification, demographics, management, and complications were analysed. Functional outcomes were undertaken with the Quick Disabilities of Arm, Shoulder and Hand and EuroQol five-dimension at mean 8.8 years post-injury. Results: In total, 677 clavicle fractures were analysed, 8.7% were lateral-end fractures (n = 59/677). The median age was 14.6 (range: 13-17) and 92% were male (n = 54/59). The incidence was 0.17 per 100,000 per year. All displaced physeal fractures (Neer IV n = 14) were managed non-operatively and of the six followed-up, all united with good outcomes. The adult type displaced fracture (Neer II) occurred in fifteen fractures, five underwent operative fixation and ten were managed non-operatively with one subsequent nonunion (n = 1/10). Those patients that underwent non-operative management (response n = 5/10, 50%) reported a median Quick Disabilities of Arm, Shoulder and Hand of 2.3 but approximately 40% reported cosmetic and outcome dissatisfaction at long-term follow-up. Conclusion: Displaced Neer II lateral-end clavicle fractures are rare in the adolescent population. Although nonunion is rare, some dissatisfaction with cosmesis persists at long-term follow-up despite good functional outcomes with non-operative management.

Fracture nonunion in long bones: A literature review of risk factors and surgical management.

Nonunion following a long bone fracture causes considerable morbidity when it occurs. Risk factors depend on specific fractures but there is a complex interplay of injury severity, comorbidities, patient medication and infection. The majority of nonunions occur after long bone fractures with the tibia, femur, forearm, humerus and clavicle predominating. Despite interest in the biological augmentation of fracture healing, the majority of nonunions can be effectively managed with conventional surgical techniques. In this review we present a review of risk factors for nonunion and the outcome following surgical management.

Monitoring of fracture healing. Update on current and future imaging modalities to predict union.

Fracture nonunion causes considerable patient morbidity and an associated burden to society. Traditional reliance on radiographs to monitor union has limitations as bridging callus of long bone fractures can take three or more months to occur. Computed Tomographic (CT) scanning is becoming increasingly popular and can evaluate bridging callus in the late stages of healing to confirm union. The use of dynamic contrast enhanced Magnetic Resonance Imaging (MRI) and advances in nuclear imaging may yield benefits in the assessment of the infected nonunion. Emerging evidence supports the use of ultrasound to detect bridging callus prior to radiographic confirmation and it may be of use to predict patients at high risk of nonunion. This paper is part of a Supplement supported by The Osteosynthesis and Trauma Care Foundation (OTCF).

Sonographic bridging callus: An early predictor of fracture union.

BACKGROUND: There is currently a lack of agreed criteria for sonographic assessment of callus and reliability between reviewers. The primary aim of this study was to determine criteria and reviewer agreement for sonographic bridging callus (SBC) on ultrasound. The secondary aim was to analyse the use of ultrasound to detect bridging callus in a prospective cohort of patients with a conservatively managed clavicle fracture. METHODS: A prospective cohort of conservatively managed displaced midshaft clavicle fractures underwent ultrasound scanning at three-, six- and 12-weeks post-injury. The main outcome was nonunion confirmed at six months on CT scanning. Five patients with confirmed nonunion were compared against a control group of 15 patients with timely union at three months. The ultrasound scans were interpreted by two blinded reviewers to evaluate sonographic callus features with agreement determined by weighted kappa. A further validation study was undertaken by four blinded reviewers using the intraclass-correlation-coefficient (ICC) using the most clinically relevant findings of the pilot work. RESULTS: At three weeks post-injury fibrocartilaginous material was present in 80% of patients (16/20). When detected this was associated with union (sensitivity 93%, specificity 60%, p = 0.03) with the inter-observer agreement rated 'fair' on kappa (0.44). At six weeks only 10% (2/20) of patients had bridging callus on radiograph but 60% (12/20) had sonographic bridging callus (SBC) and when present all united (sensitivity 80%, specificity 100%, p = 0.002). At 12 weeks, bridging callus was present on both radiographs and ultrasound in all patients that united (n = 15, sensitivity 100%, specificity 100%, p < 0.001). No patient that developed a nonunion at six months post-injury had SBC at any time point. At six-weeks the absence of SBC had a positive predictive value for nonunion of 63% of patients (5/8) and by 12 weeks it was 100% (5/5). The SBC detection rated 'very strong' for intra- (kappa 0.92) and inter-observer agreement (kappa 0.84). The ICC of SBC at six-weeks with four blinded reviewers was 0.82 (95% confidence interval 0.68-0.91). CONCLUSIONS: This is the first study to establish time specific ultrasound fracture findings with a repeatable technique and assess the agreement between blinded reviewers.

What is the role of ultrasound in fracture management?: Diagnosis and therapeutic potential for fractures, delayed unions, and fracture-related infection.

OBJECTIVES: The aim of this study was to review the current evidence and future application for the role of diagnostic and therapeutic ultrasound in fracture management. METHODS: A review of relevant literature was undertaken, including articles indexed in PubMed with keywords "ultrasound" or "sonography" combined with "diagnosis", "fracture healing", "impaired fracture healing", "nonunion", "microbiology", and "fracture-related infection". RESULTS: The use of ultrasound in musculoskeletal medicine has expanded rapidly over the last two decades, but the diagnostic use in fracture management is not routinely practised. Early studies have shown the potential of ultrasound as a valid alternative to radiographs to diagnose common paediatric fractures, to detect occult injuries in adults, and for rapid detection of long bone fractures in the resuscitation setting. Ultrasound has also been shown to be advantageous in the early identification of impaired fracture healing; with the advent of 3D image processing, there is potential for wider adoption. Detection of implant-related infection can be improved by ultrasound mediated sonication of microbiology samples. The use of therapeutic ultrasound to promote union in the management of acute fractures is currently a controversial topic. However, there is strong in vitro evidence that ultrasound can stimulate a biological effect with potential clinical benefit in established nonunions, which supports the need for further investigation. CONCLUSION: Modern ultrasound image processing has the potential to replace traditional imaging modalities in several areas of trauma practice, particularly in the early prediction of impaired fracture healing. Further understanding of the therapeutic application of ultrasound is required to understand and identify the use in promoting fracture healing.Cite this article: J. A. Nicholson, S. T. J. Tsang, T. J. MacGillivray, F. Perks, A. H. R. W. Simpson. What is the role of ultrasound in fracture management? Diagnosis and therapeutic potential for fractures, delayed unions, and fracture-related infection. Bone Joint Res 2019;8:304-312. DOI: 10.1302/2046-3758.87.BJR-2018-0215.R2.

Routine fixation of displaced midshaft clavicle fractures is not cost-effective: a cost analysis from a randomized controlled trial.

AIMS: The primary aim of this study was to establish the cost-effectiveness of the early fixation of displaced midshaft clavicle fractures. PATIENTS AND METHODS: A cost analysis was conducted within a randomized controlled trial comparing conservative management (n = 92) versus early plate fixation (n = 86) of displaced midshaft clavicular fractures. The incremental cost-effectiveness ratio (ICER) was used to express the cost per quality-adjusted life-year (QALY). The Six-Dimension Short-Form Health Survey (SF-6D) score was used as the preference-based health index to calculate the cost per QALY at 12 months after the injury. RESULTS: The mean 12-month SF-6D was 0.9522 (95% confidence interval (CI) 0.9355 to 0.9689) following conservative management and 0.9607 (95% CI 0.9447 to 0.9767) following fixation, giving an advantage for fixation of 0.0085, which was not statistically significant (p = 0.46). The mean cost per patient was £1322.69 for conservative management and £5405.32 for early fixation. This gave an ICER of £480 309.41 per QALY. For a threshold of £20 000 per QALY, the benefit of fixation would need to be present for 24 years to be cost-effective compared with conservative treatment. Linear regression analysis identified nonunion as the only factor to adversely influence the SF-6D at 12 months (p < 0.001). CONCLUSION: Routine plate fixation of displaced midshaft clavicular fractures is not cost-effective. Nonunion following conservative management has an increased morbidity with comparable expense to early fixation. This may suggest that a targeted approach of fixation in patients who are at higher risk of nonunion would be more cost-effective than the routine fixation of all displaced fractures. Cite this article: Bone Joint J 2019;101-B:995-1001.

Cost-effectiveness and satisfaction following arthroscopic rotator cuff repair: does age matter?.

AIMS: The aim of this study was to investigate the influence of age on the cost-effectiveness of arthroscopic rotator cuff repair. PATIENTS AND METHODS: A total of 112 patients were prospectively monitored for two years after arthroscopic rotator cuff repair using the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH), the Oxford Shoulder Score (OSS), and the EuroQol five-dimension questionnaire (EQ-5D). Complications and use of healthcare resources were recorded. The incremental cost-effectiveness ratio (ICER) was used to express the cost per quality-adjusted life-year (QALY). Propensity score-matching was used to compare those aged below and above 65 years of age. Satisfaction was determined using the Net Promoter Score (NPS). Linear regression was used to identify variables that influenced the outcome at two years postoperatively. RESULTS: A total of 92 patients (82.1%) completed the follow-up. Their mean age was 59.5 years (sd 9.7, 41 to 78). There were significant improvements in the mean DASH (preoperative 47.6 vs one-year 15.3; p < 0.001) and OSS scores (26.5 vs 40.5; p < 0.001). Functional improvements were maintained with no significant change between one and two years postoperatively. The mean preoperative EQ-5D was 0.54 increasing to 0.81 at one year (p < 0.001) and maintained at 0.86, two years postoperatively. There was no significant difference between those aged below or above 65 years of age with regards to postoperative shoulder function or EQ-5D gains. Smoking was the only characteristic that significantly adversely influenced the EQ-5D at two years postoperatively (p = 0.005). A total of 87 were promoters and five were passive, giving a mean NPS of 95 (87/92). The total mean cost per patient was £3646.94 and the mean EQ-5D difference at one year was 0.2691, giving a mean ICER of £13 552.36/QALY. At two years, this decreased further to £5694.78/QALY. This was comparable for those aged below or above 65 years of age (£5209.91 vs £5525.67). Smokers had an ICER that was four times more expensive. CONCLUSION: Arthroscopic rotator cuff repair results in excellent patient satisfaction and cost-effectiveness, regardless of age. Cite this article: Bone Joint J 2019;101-B:860-866.

Identification of Cystic Lesions by Secondary Screening of Familial Pancreatic Cancer (FPC) Kindreds Is Not Associated with the Stratified Risk of Cancer.

OBJECTIVES: Intraductal papillary mucinous neoplasms (IPMNs) are associated with risk of pancreatic ductal adenocarcinoma (PDAC). It is unclear if an IPMN in individuals at high risk of PDAC should be considered as a positive screening result or as an incidental finding. Stratified familial pancreatic cancer (FPC) populations were used to determine if IPMN risk is linked to familial risk of PDAC. METHODS: This is a cohort study of 321 individuals from 258 kindreds suspected of being FPC and undergoing secondary screening for PDAC through the European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer (EUROPAC). Computerised tomography, endoscopic ultrasound of the pancreas and magnetic resonance imaging were used. The risk of being a carrier of a dominant mutation predisposing to pancreatic cancer was stratified into three even categories (low, medium and high) based on: Mendelian probability, the number of PDAC cases and the number of people at risk in a kindred. RESULTS: There was a median (interquartile range (IQR)) follow-up of 2 (0-5) years and a median (IQR) number of investigations per participant of 4 (2-6). One PDAC, two low-grade neuroendocrine tumours and 41 cystic lesions were identified, including 23 IPMN (22 branch-duct (BD)). The PDAC case occurred in the top 10% of risk, and the BD-IPMN cases were evenly distributed amongst risk categories: low (6/107), medium (10/107) and high (6/107) (P = 0.63). CONCLUSIONS: The risk of finding BD-IPMN was independent of genetic predisposition and so they should be managed according to guidelines for incidental finding of IPMN.

Native hip dislocation at acetabular fracture predicts poor long-term outcome.

AIM: The aim of this study was to evaluate the long-term clinical outcomes and complications following an acetabular fracture associated with a posterior hip dislocation compared to those without dislocation. PATIENTS & METHODS: A retrospective cohort study of 113 patients (mean age 42 (14-95), 77% male) with acetabular fracture dislocations compared to 367 patients with acetabular fractures without dislocation (mean age 54 (16-100), 66% male) treated from 1988 to 2010. Patient characteristics, complications, reoperations, and conversion to total hip arthroplasty (THA) were recorded. Long term patient reported outcomes (Oxford Hip Score and SF-12) were measured at mean follow up 9.7 years (5-26). RESULTS: At long-term follow up 12/113 (11%) patients had died and 22/113 (19%) were lost. Isolated posterior wall fracture was the most common fracture associated with dislocation. Patients with dislocation were more likely to be younger and male with higher Injury Severity Scores (ISS). There was no significant difference in radiographic post-traumatic osteoarthritis development between fractures with and without dislocation (p = 0.246). Sciatic nerve palsy (12% Vs 1%, p < 0.001) and avascular necrosis (AVN) (11% Vs 1%, p < 0.001) were more common when dislocation was present. AVN was associated with increasing age and hypotension on arrival to the emergency department. Ten-year native hip survival was worse following fracture dislocations compared to fractures without dislocation: 75.1% (65.7-84.5 95% CI) Vs 90.7% (87.0-94.4), p < 0.001. Significant predictors of THA requirement were older age, particularly age >55 years at fracture, and increased ISS. Long-term OHS was worse in fractures with dislocations (33.6 ± 13.1 Vs 37.0 ± 14.0, p = 0.016). CONCLUSION: Acetabular fractures with an associated dislocation have worse long-term functional outcomes with higher rates of complications and conversion to late THA compared to acetabular fractures without a dislocation.

Video-assisted anal fistula treatment: a high volume unit initial experience.

Introduction Perianal fistulas are a common problem. Video-assisted anal fistula treatment is a new technique for the management of this difficult condition. We describe our initial experience with the technique to facilitate the treatment of established perianal fistulas. Methods We reviewed a prospectively maintained database relating to consecutive patients undergoing video-assisted anal fistula treatment in a single unit. Results Seventy-eight consecutive patients had their perianal fistulas treated with video-assistance from November 2014 to June 2016. Complete follow-up data were available in 74 patients, with median follow-up of 14 months (interquartile range 7-19 months). There were no complications and all patients were treated as day cases. Most patients had recurrent disease, with 57 (77%) having had previous fistula surgery. At follow-up, 60 (81%) patients reported themselves 'cured' (asymptomatic) including 5 patients with Crohn's disease and one who had undergone 10 previous surgical procedures. Logistical stepwise regression did not demonstrate any statistically significant factors that may have been considered to affect outcome (age, gender, diabetes, previous I&D, Crohn's disease, smoking, type of fistula). Conclusions Our data have shown that video-assisted anal fistula treatment is safe and effective in the management of perianal fistulas in our patients and this suggests it may be applied to all patients regardless of comorbidity, underlying pathology or type of fistula.

Single bundle anterior cruciate reconstruction does not restore normal knee kinematics at six months: an upright MRI study.

Abnormal knee kinematics following reconstruction of the anterior cruciate ligament may exist despite an apparent resolution of tibial laxity and functional benefit. We performed upright, weight-bearing MR scans of both knees in the sagittal plane at different angles of flexion to determine the kinematics of the knee following unilateral reconstruction (n = 12). The uninjured knee acted as a control. Scans were performed pre-operatively and at three and six months post-operatively. Anteroposterior tibial laxity was determined using an arthrometer and patient function by validated questionnaires before and after reconstruction. In all the knees with deficient anterior cruciate ligaments, the tibial plateau was displaced anteriorly and internally rotated relative to the femur when compared with the control contralateral knee, particularly in extension and early flexion (mean lateral compartment displacement: extension 7.9 mm (sd 4.8), p = 0.002 and 30° flexion 5.1 mm (sd 3.6), p = 0.004). In all ten patients underwent post-operative scans. Reconstruction reduced the subluxation of the lateral tibial plateau at three months, with resolution of anterior displacement in early flexion, but not in extension (p = 0.015). At six months, the reconstructed knee again showed anterior subluxation in both the lateral (mean: extension 4.2 mm (sd 4.2), p = 0.021 and 30° flexion 3.2 mm (sd 3.3), p = 0.024) and medial compartments (extension, p = 0.049). Our results show that despite improvement in laxity and functional benefit, abnormal knee kinematics remain at six months and actually deteriorate from three to six months following reconstruction of the anterior cruciate ligament.

Mesenteric panniculitis in Merseyside: a case series and a review of the literature.

Mesenteric panniculitis (also known as mesenteric manifestation of Weber-Christian disease, isolated lipodystrophy and mesenteric lipogranuloma), a benign inflammatory or fibrotic change in the mesentery of the bowel, is a rare diagnosis, particularly in the UK. Some 213 cases have been reported in the world-wide literature, just six from the UK. We present four cases of mesenteric panniculitis in Merseyside and review the literature surrounding this poorly understood phenomenon. Four patients who attended surgical out-patients with vague abdominal symptoms, and in two cases a palpable mass, were sent for abdominal computed tomography (CT) scan. One patient was admitted as an emergency with abdominal pain. In each patient there were clear signs of mesenteric panniculitis, first described in 1924. The 'classical' signs of mesenteric panniculitis seen on CT have been argued by some to be pathognemonic of the disease. In two cases, the patients underwent laparoscopic biopsies to confirm the diagnosis. We discuss the literature relating to mesenteric panniculitis, theories about its aetiology, confirmation of the diagnosis and consider the possibility that it is not actually as rare as we think. We suggest that it is rather under diagnosed due to the relative ignorance of the condition amongst both surgeons and radiologists the UK compared to the US, where mesenteric panniculitis is far more widely reported.

Caries prevalence four years after the end of a randomised controlled trial.

This study measured dental caries in children after cessation of a 30-month randomised clinical trial in which the intervention group received supervised toothbrushing once a day at school with 1,000 ppm fluoride toothpaste and a home support package encouraging twice-daily toothbrushing. The non-intervention group did not brush at school or receive the home support package. Children were aged 5 years at baseline and were examined every 6 months during the trial, then at 6, 18, 30 and 54 months after the end of the trial. Significantly less caries developed in first permanent molars of intervention children at the end of the trial. Of the 428 children who were examined at the end of the trial 329 (77%) were examined 54 months later when the children were aged 12 years on average. The intervention group still had less caries (D3FS caries increment 1.62) than the non-intervention children (D3FS caries increment 2.65, p < 0.05). Prolonged benefits have been found for intervention children principally in less caries in first permanent molars. Further follow-up at an age when the second molars and premolars have all erupted will help determine whether this benefit is due to a long-term behavioural change or a prolonged biological effect.

The effect of oral care feed-back devices on plaque removal and attitudes towards oral care.

OBJECTIVES: Two studies were carried out to investigate whether the effect of specific oral care feed-back devices would result in better plaque removal (Study 1) and lead to changes in attitudes and views relating to oral health (Study 2). The objective of the first study was to compare the ability of a toothbrush system consisting of a new toothbrush plus plaque disclosing tablet (SIGNAL Integral) to remove supra-gingival plaque to that of a marketed toothbrush (Oral B Cross Action) following a single unsupervised brushing. METHODS: Study 1 had a cross-over design and included 21 healthy adult volunteers. Subjects refrained from any form of oral hygiene for 24 hours prior to each test session. Plaque levels (Modified Quigley-Hein Plaque index) were assessed prior to and following each unsupervised brushing. When the new toothbrush was used, subjects self-disclosed their plaque with a disclosing tablet (erythrosine) immediately prior to brushing. At each occasion, brushing time (in sec) was also recorded. Study 2 had a two-cell, parallel design (test and control group) and lasted for five days. Healthy adult volunteers were enrolled. Subjects in the test group (n = 30) were given a fluoride toothpaste and four saliva test strips to use at home. The saliva test strip is designed to change colour in the pH range of 6.5 to 10, allowing the user to verify the effect of brushing. The control group (n = 29) received no saliva test strips. Subjects completed a questionnaire after 4 days of product use. RESULTS: In Study 1, significantly more plaque was removed (p < 0.05) and brushing time was increased by more than 20% when subjects used the new toothbrush together with the disclosing tablet compared to brushing with the marketed toothbrush. In Study 2, significant increases in motivation relating to oral hygiene were found in the test group who had been using the saliva test strip. CONCLUSION: The two studies have provided significant evidence that the provision of feed-back devices in an oral care context can lead to improved removal of plaque and increased motivation.

Photocatalytic oxidation of NOx gases using TiO2: a surface spectroscopic approach.

The bandgap of solid-state TiO2 (3.2 eV) enables it to be a useful photocatalyst in the ultraviolet (lambda < 380 nm) region of the spectrum. A clean TiO2 surface in the presence of sunlight therefore enables the removal of harmful NOx gases from the atmosphere by oxidation to nitrates. These properties, in addition to the whiteness, relative cheapness and non-toxicity, make TiO2 ideal for the many de-NOX catalysts that are currently being commercially exploited both in the UK and Japan for concrete paving materials in inner cities. There is need, however, for further academic understanding of the surface reactions involved. Hence, we have used surface specific techniques, including X-ray photoelectron spectroscopy and Raman spectroscopy, to investigate the NOx adsorbate reaction at the TiO2 substrate surface.

A randomised controlled trial of the efficacy of supervised toothbrushing in high-caries-risk children.

Scottish children have one of the highest levels of caries experience in Europe. Only 33% of 5-year-old children in Dundee who developed caries in their first permanent molars by 7 brushed their teeth twice a day. High-caries-risk children should benefit if they brush more often with fluoridated toothpaste. The aim of this clinical trial was to determine the reduction in 2-year caries increment that can be achieved by daily supervised toothbrushing on school-days with a toothpaste containing 1,000 ppm fluoride (as sodium monofluorophosphate) and 0.13% calcium glycerophosphate, combined with recommended daily home use, compared to a control group involving no intervention other than 6-monthly clinical examinations. Five hundred and thirty-four children, mean age 5.3, in schools in deprived areas of Tayside were recruited. Each school had two parallel classes, one randomly selected to be the brushing class and the other, the control. Local mothers were trained as toothbrushing supervisors. Children brushed on school-days and received home supplies. A single examiner undertook 6-monthly examinations recording plaque, caries (D(1) level), and used FOTI to supplement the visual caries examination. For children in the brushing classes, the 2-year mean caries increment on first permanent molars was 0.81 at D(1) and 0.21 at D(3) compared to 1.19 and 0.48 for children in the control classes (significant reductions of 32% at D(1) and 56% at D(3)). In conclusion, high-caries-risk children have been shown to have significantly less caries after participating in a supervised toothbrushing programme with a fluoridated toothpaste.

An abbreviated caries clinical trial design validated over 24 months.

Conventional caries trials last from 24 to 36 months. This study evaluated whether the previously established difference in efficacy between 1000- and 2500-ppm-fluoride dentifrices could be detected after 12 months. Caries was assessed by clinical visual assessment (CVA-simplified version of Dundee Selectable Threshold Method - DSTM), bitewing radiography, and Fiber Optic Transillumination (FOTI). Changes in status for individual surfaces were classified by means of pre-prepared matrices as 0 (unchanged), +1 (initiation or progression), or -1 (regression) and summed for each subject to yield an event score. Mean group event scores were calculated for each product. DSTM at the D(1) [enamel and dentin] threshold showed significant inter-group differences in mean event scores (p < 0.003) and D(1)MFS increment (< 0.007) at 12 months; these were confirmed at 24 months by traditional increment analysis (CVA & FOTI at the D(3) (dentin only) threshold + radiography, p < 0.03). This study confirms the validity of an abbreviated trial protocol.

Diagnosis of pancreatic carcinoma by fine needle aspiration cytology and computerized cytomorphometry.

Eighty-one fine needle aspirations (FNAs) of pancreatic masses were performed between 1980 and 1988. Histologic or clinical follow-up was available for correlation with 78 aspirates. The FNA cytologic diagnosis of pancreatic carcinoma had a sensitivity of 79% and a specificity of 91%. Fifteen of the FNA specimens were examined with the Zeiss IBAS image analysis system to determine nuclear area, form (shape), diameter, density and integrated optical density (IOD). Nuclear area and IOD correlated most highly with the final diagnoses. Negative aspirates from benign cases and "false negatives" from malignant cases had similar morphometric values. Cells from adenocarcinoma had greater nuclear area and IOD values in cases cytologically labeled positive than in cytologically suspicious cases. Diagnoses based upon IOD values had a sensitivity and a specificity of 100% and 86%, respectively, while the use of nuclear area measurements produced values of 100% and 100%, respectively. These data indicate that nuclear area and IOD measurements can be valuable adjuncts to qualitative cytology for the diagnosis of pancreatic fine needle aspirates.

Nitinol arch wire in a simulated oral environment: changes in mechanical properties.

Changes in the mechanical properties of a nickel-titanium orthodontic alloy, nitinol (0.016-inch arch wires), were studied in a simulated oral environment across time, at various levels of acidity, and at different amounts of static deflection. Significant decreases in specific mechanical properties were observed in these incubated wires compared with a group kept dry and unstressed. Ultimate tensile strain, modulus of elasticity, and 0.2% yield strength each decreased. Acidity (pH 3 to 7) and amount of deflection (0 to 4 mm in a 10-mm span) did not affect the wire, but there was a significant, monotonic decrease in yield strength with time in the simulated oral environment. By 4 months this measure of susceptibility to permanent deformation increased by 15%. Consequently, long-term use (or reuse) of a nitinol wire may be associated with a modest, but statistically significant, degradation in performance, notably in the limit of the wire's elasticity.