Dutch Outcome in Implantable Cardioverter-Defibrillator Therapy: Implantable Cardioverter-Defibrillator-Related Complications in a Contemporary Primary Prevention Cohort.

Background One third of primary prevention implantable cardioverter-defibrillator patients receive appropriate therapy, but all remain at risk of defibrillator complications. Information on these complications in contemporary cohorts is limited. This study assessed complications and their risk factors after defibrillator implantation in a Dutch nationwide prospective registry cohort and forecasts the potential reduction in complications under distinct scenarios of updated indication criteria. Methods and Results Complications in a prospective multicenter registry cohort of 1442 primary implantable cardioverter-defibrillator implant patients were classified as major or minor. The potential for reducing complications was derived from a newly developed prediction model of appropriate therapy to identify patients with a low probability of benefitting from the implantable cardioverter-defibrillator. During a follow-up of 2.2 years (interquartile range, 2.0-2.6 years), 228 complications occurred in 195 patients (13.6%), with 113 patients (7.8%) experiencing at least one major complication. Most common ones were lead related (n=93) and infection (n=18). Minor complications occurred in 6.8% of patients, with lead-related (n=47) and pocket-related (n=40) complications as the most prevailing ones. A surgical reintervention or additional hospitalization was required in 53% or 61% of complications, respectively. Complications were strongly associated with device type. Application of stricter implant indication results in a comparable proportional reduction of (major) complications. Conclusions One in 13 patients experiences at least one major implantable cardioverter-defibrillator-related complication, and many patients undergo a surgical reintervention. Complications are related to defibrillator implantations, and these should be discussed with the patient. Stricter implant indication criteria and careful selection of device type implanted may have significant clinical and financial benefits.

Are There Differences in Accuracy or Outcomes Scores Among Navigated, Robotic, Patient-specific Instruments or Standard Cutting Guides in TKA? A Network Meta-analysis.

BACKGROUND: Several kinds of cutting guides, including patient-specific instrumentation, navigation, standard cutting guides, accelerometer-based navigation, and robotic guidance, are available to restore a planned alignment during TKA. No previous study has simultaneously compared all of these devices; a network meta-analysis is an especially appealing method because it allows comparisons across approaches that were not compared head-to-head in individual randomized controlled trials. QUESTIONS/PURPOSES: We performed a network meta-analysis to determine whether novel approaches to achieving implant alignment, such as patient-specific instrumentation, navigation, accelerometer-based navigation, and robotic guidance, provide any advantage over standard cutting guides in terms of: (1) hip-knee-ankle (HKA) alignment outliers greater than ± 3°, (2) outcome scores (1989 - Knee Society Score and WOMAC score) measured 6 months after surgery, or (3) femoral and tibial implant malalignment (greater than ± 3°), taken separately, in the frontal and sagittal plane, as well as other secondary outcomes including validated outcome scores 1 and 2 years after surgery. METHODS: In our network meta-analysis, we included randomized controlled trials comparing the different cutting guides by using at least one of the previously specified criteria, without limitation on language or date of publication. We searched electronic databases, major orthopaedic journals, proceedings of major orthopaedic meetings, ClinicalTrials.gov, and the World Health Organization's International Clinical Trials Registry Platform until October 1, 2018. This led to the inclusion of 90 randomized controlled trials involving 9389 patients (mean age 68.8 years) with 10,336 TKAs. Two reviewers independently selected trials and extracted data. The primary outcomes were the proportion patients with malalignment of the HKA angle (defined as HKA > 3° from neutral) and the Knee Society Score and WOMAC scores at 6 months postoperatively. We combined direct and indirect comparisons using a Bayesian network meta-analysis framework to assess and compare the effect of different cutting guides on outcomes. Bayesian estimates are based on the posterior distribution of an endpoint and are called credible intervals. Usually the 95% credible interval, corresponding to a posterior probability of 0.95 that the endpoint lies in the interval, is computed. Unlike the frequentist approach, the Bayesian approach does not allow the calculation of the p value. RESULTS: The proportion of HKA outliers was lower with navigation than with patient-specific instrumentation (risk ratio 0.46 [95% credible interval (CI) 0.34 to 0.63]) and standard cutting guides (risk ratio 0.45 [95% CI 0.37 to 0.53]); however, this corresponded to an actual difference of only 12% of patients for navigation versus 21% of patients for patient-specific instrumentation, and 12% of patients for navigation versus 25% for standard cutting guides. We found no differences for other comparisons between different cutting guides, including robotics and the accelerometer. We found no differences in the Knee Society Score or WOMAC score between the different cutting guides at 6 months. Regarding secondary outcomes, navigation reduced the risk of frontal and sagittal malalignments for femoral and tibial components compared with the standard cutting guides, but none of the other cutting guides showed superiority for the other secondary outcomes. CONCLUSIONS: Navigation resulted in approximately 10% fewer patients having HKA outliers of more than 3°, without any corresponding improvement in validated outcomes scores. It is unknown whether this incremental reduction in the proportion of patients who have alignment outside a window that itself has been called into question will justify the increased costs and surgical time associated with the approach. We believe that until or unless these new approaches either (1) convincingly demonstrate superior survivorship, or (2) convincingly demonstrate superior outcomes, surgeons and hospitals should not use these approaches since they add cost, have a learning curve (during which some patients may be harmed), and have the risks associated with uncertainty of novel surgical approaches. LEVEL OF EVIDENCE: Level I, therapeutic study.

Mixed ceramic combinations in primary total hip arthroplasty achieved reassuring mid-to-longterm outcomes.

INTRODUCTION: Ceramic-on-ceramic couplings demonstrated to be reliable bearings in primary total hip arthroplasty (THA), with long-term remarkable results. Like-on-like configurations were widely described. On the contrary, mixed material combinations from the same manufacturer, Delta-on-Forte or Forte-on-Delta, were poorly studied. In particular, it is unknown whether mixed ceramic combinations are more at risk of ceramic fractures. Thus, a registry study was conducted to investigate the long-term survival rates and reasons for revision of mixed ceramic combinations. A comparison with Delta-on-Delta couplings was also performed. MATERIALS AND METHODS: The regional arthroplasty registry RIPO was enquired about three cohorts of ceramic bearings (head-on-liner: Delta-on-Forte, Forte-on-Delta, Delta-on-Delta). Demographics, survival rates and reasons for revision were evaluated and compared. RESULTS: In total, 346 (1.5%) implants had a Delta-on-Forte coupling (mean follow-up: 6.4 years). In total, 1163 (5%) THAs had a Forte-on-Delta articulation (mean follow-up: 8.2 years). Delta-on-Delta surfaces were implanted in 21,874 (93.5%) hips (mean follow-up: 3.9 years). Mixed material combinations were implanted between 2003 and 2007. The survival rates of the three cohorts were similar and were higher than 95% at 10 years. In Forte-on-Delta group, four liners failed (0.3% of the implants), whereas ceramic fractures occurred in 15 cases (0.1%) in Delta-on-Delta couplings (3 heads and 12 liners). Considering ceramic fracture as endpoint, there was no significant difference between the three survival rates. CONCLUSIONS: Mixed ceramic bearing configurations from the same manufacturer in primary THA showed mid-to-longterm dependable outcomes, not inferior to the most recent like-on-like ceramic bearings. No additional risks of ceramic fractures were evident. Thus, closer follow-ups are not required.

Identifying a Break in the Chain: An Analysis of Where Ureteroscope Damage Occurs in the Hospital Cycle.

OBJECTIVE: To assess the timing and variables associated with damage to flexible ureteroscopes (fURS) at our institution. Flexible ureteroscopy is an important modality in the treatment of benign and malignant conditions of the upper urinary tract. While the durability and versatility of fURS have improved considerably, repair costs remain high and time out of commission diminishes workflow. After purchasing new digital fURS, we studied how and when these instruments were being damaged. MATERIALS AND METHODS: Between September 1, 2017 and June 30, 2018, we performed leak testing on fURS both before and after use. We gathered intraoperative data related to the user, the surgical indication, and the associated tools used in all cases that employed a digital or fiber optic fURS. Categorical and continuous variables were analyzed to identify risk factors for intraoperative fURS damage. RESULTS: During the study period, complete data was gathered for 281 cases. Twenty-two fURS failed leak testing indicating an overall leak failure rate of 7.8%. Of these, 15 failed leak testing preoperatively indicating nonoperative damage occurring sometime during transport, handling, or sterile processing. The other 7 failures occurred during the procedures. No intraoperative variables were significantly associated with failures. CONCLUSION: Our institutional leak failure rate is 8% (22/281). The majority of these failures did not occur during surgery. Of the 7 that occurred during surgery, larger stone burden and higher wattage showed mild association. Ongoing evaluation will target minimizing fURS damage outside of the operating room.

Retrospective Comparative Study of Side-by-Side and Stent-in-Stent Metal Stent Placement for Hilar Malignant Biliary Obstruction.

BACKGROUND: In patients with unresectable hilar malignant biliary obstruction (MBO), bilateral metal stent placement is recommended. However, treatment selection between partially stent-in-stent (SIS) and side-by-side (SBS) methods is still controversial. STUDY: Clinical outcomes of bilateral metal stent placement by SBS and SIS methods for hilar MBO were retrospectively studied in four Japanese centers. While large-cell-type uncovered metal stents were placed above the papilla in SIS, braided-type uncovered metal stents were placed across the papilla in SBS. RESULTS: A total of 64 patients with hilar MBO (40 SIS and 24 SBS) were included in the analysis. Technical success rate was 100% in SIS and 96% in SBS. Functional success rate was 93% in SIS and 96% in SBS. Early adverse event rates were higher in SBS (46%) than in SIS (23%), though not statistically significant (P = 0.09). Post-procedure pancreatitis was exclusively observed in SBS group (29%). Recurrent biliary obstruction rates were 48% and 43%, and the median time to recurrent biliary obstruction was 169 and 205 days in SIS and SBS, respectively. CONCLUSIONS: Other than a trend to higher adverse event rates including post-procedure pancreatitis in SBS, clinical outcomes of SIS and SBS methods were comparable in patients with unresectable hilar MBO.

Utility and Safety of a Novel Fully Covered Metal Stent in Unresectable Distal Malignant Biliary Obstruction.

BACKGROUND: Self-expandable metal stents (SEMSs) are widely used in patients with distal malignant biliary obstruction. A SEMS that can avoid occlusion as much as possible is desirable. AIMS: The aim of this multicenter single-arm prospective study was to assess the clinical effectiveness and safety of a novel fully covered braided SEMS. METHODS: We enrolled consecutive patients with distal malignant biliary obstruction between February 2016 and November 2017 at ten tertiary-care medical centers. RESULTS: We included 79 patients with a median age of 76 years; 47 (59.5%) patients were men. The technical and clinical success rate was 98.7% and 93.6%, respectively. Recurrent biliary obstruction occurred in 14 patients (17.9%); stent ingrowth, overgrowth, migration, and other occurred in five (6.4%), four (5.1%), four (5.1%), and one (1.3%) patients, respectively. All reinterventions in patients with recurrent biliary obstruction were successful via the transpapillary approach. Adverse events occurred in 15 patients (19.2%); cholangitis, pancreatitis, and others occurred in ten (12.8%), three (3.8%), and two (2.6%) patients, respectively. The stent patency probability at 6 months was 48.5%. Median time to stent patency was 171 days, median time to recurrent biliary obstruction was 536 days, and median survival time was 195 days. CONCLUSIONS: We confirmed the utility and safety of a novel fully covered braided SEMS with low axial force and high radial force in patients with malignance biliary obstruction. This novel SEMS is recommended in patients with distal malignant biliary obstruction.

Implantation Time Has No Effect on the Morphology and Extent of Previously Reported "Degradation" of Prolene Pelvic Mesh.

OBJECTIVES: Prolene polypropylene ("Prolene") meshes demonstrate no in vivo degradation, yet some claim degradation continues until no more Prolene polypropylene can be oxidized. We studied whether implantation time affects the morphology/extent of previously reported as cracking/degradation of completely cleaned Prolene explants. METHODS: Urogynecological explants (248 patients) were collected. After excluding non-Prolene/unknown meshes and those without known implantation times, completely cleaned explants (n = 205; 0.2-14.4 years implantation) were analyzed with light microscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy. Based on implant times and storage (fixative or dry), representative specimens were randomly selected for comparison. Controls were unused ("exemplar") TVT specimens with and without intentional oxidation via ultraviolet light exposure. RESULTS: Prolene explants included 31 dry (18 TVT; 7 Prolift; 4 Gynemesh; 2 others) and 174 wet (87 TVT; 47 Prolift; 10 Gynemesh; 30 others) specimens. Specimens had similar morphologies before cleaning. Progressive cleaning removed tissue and cracked tissue-related material exposing smooth, unoxidized, and nondegraded fibers, with no visible gradient-type/ductile damage. Fourier transform infrared spectroscopy of the explants confirmed progressive loss of proteins. Cleaning intentionally oxidized exemplars did not remove oxidized carbonyl frequencies and showed deep cracks and gross fiber rupture/embrittlement, unlike the explants and nonoxidized exemplars. CONCLUSIONS: If in vivo Prolene degradation exists, there should be wide-ranging crack morphology and nonuniform crack penetration, as well as more cracking, degradation, and physical breakage for implants of longer implantation times, but this was not the case. There is no morphologic or spectral/chemical evidence of Prolene mesh degradation after up to 14.4 years in vivo.

Recurrent pump thrombosis is common after axial continuous-flow left ventricular assist device exchange.

In selected patients with left ventricular assist device-associated infection or malfunction, pump exchange may become necessary after conservative treatment options fail and heart transplantation is not readily available. We examined the survival and complication rate in patients (⩾19 years of age) who underwent HeartMate II to HeartMate II exchange at our institution from 1 January 2010 to 28 February 2018. Clinical outcomes were analyzed and compared for patients who underwent exchange for pump thrombosis (14 patients), breach of driveline integrity (5 patients), and device-associated infection (2 patients). There were no differences in 30-day mortality (p = 0.58), need for temporary renal replacement therapy (p = 0.58), right ventricular mechanical support (p = 0.11), and postoperative stroke (p = 0.80) among groups. Survival at 1 year was 90% ± 7% for the whole cohort and 85% ± 10% for those who underwent exchange for pump thrombosis. In patients exchanged for device thrombosis, freedom from re-thrombosis and survival free from pump re-thrombosis at 1 year were 49% ± 16% and 42% ± 15%, respectively. No association of demographic and clinical variables with the risk of recurrent pump thrombosis after the first exchange was identified. Survival after left ventricular assist device exchange compares well with published results after primary left ventricular assist device implantation. However, recurrence of thrombosis was common among patients who required a left ventricular assist device exchange due to pump thrombosis. In this sub-group, consideration should be given to alternative strategies to improve the outcomes.

Catheter tips are a possible resource for biological study on catheter failure.

Few studies have investigated the molecular mechanisms of catheter failure (CF). Herein, we performed histological and molecular biological analyses of the catheter tip to demonstrate its potential as a resource for biological investigation. Additionally, we searched for risk factors for the development of inflammation and coagulation, which are pathological conditions clarified by biological analysis. The CF group included 30 failed catheters involving thrombus and subcutaneous edema identified by ultrasonography. The No-CF group included 26 catheters with no complications. The removed catheter tips were fixed for hematoxylin-eosin (HE) staining with the application of a real-time reverse transcriptase polymerase chain reaction for eukaryotic 18S ribosomal RNA (rRNA), interleukin 1ß, tumor necrosis factor α, tissue plasminogen activator, and plasminogen activator inhibitor 1 (SERPINE1). HE staining identified attached nuclear cells on the inner surfaces of both CF and No-CF catheters. The 18S rRNA was amplified in all samples. The expression level of SERPINE1 was significantly higher in the CF group than in the No-CF group (p = 0.01), whereas the expression levels of other genes did not differ between the groups. Symptoms of CF associated with the expression of SERPINE1 were analyzed. The catheter being in contact with blood vessels during placement was a suggested factor related to the high expression of SERPINE1 (p = 0.04). Catheter tips are a potential resource for biological investigation, and expression analysis of the attached cells can reflect the pathological condition of the catheterized tissue. Further studies using catheter tips are required to elucidate the molecular mechanisms of CF.

Radiotherapy of patients with cardiac implantable electronic devices according to the DEGRO/DGK guideline-is the risk of relevant errors overestimated?

PURPOSE: Ionizing radiation is able to cause severe damage to cardiac implantable electronic devices (CIED). In Germany, the DEGRO/DGK guideline recommends close monitoring of patients with CIEDs undergoing radiotherapy (RT). Nevertheless, especially in the era of intensity-modulated techniques and predominant use of 6 MV photons, errors of CIEDs are rare events. Therefore, we performed daily CIED controls and hypothesized that no relevant device interaction would occur in our cohort. METHODS: From 2014 to 2018, we collected data of 51 patients (62 courses) with daily interrogation (n = 1046) of CIED. The dose to the skin above the CIED was measured by semiconductor or ion chamber dosimetry at least once per RT course. In many cases the dose was also calculated. RESULTS: The prescribed dose to the planning target volume (PTV) ranged from 7.5 to 78.0 Gy (IQR 27.8-61.0 Gy). The median measured cumulative dose to the skin above the CIED was 0.17 Gy, whereas the median calculated dose was 1.03 Gy. No error occurred in the group with maximum beam energy >10 MeV. Three events without clinical relevance could be recognized in the group with an intensity-modulated technique at 6 MV. None of the three concerned devices were located directly within the PTV. CONCLUSION: Errors of CIEDs during RT are rare events. The approach according to the DEGRO/DGK guideline is safe, but also consumes resources. In our cohort it was not compulsory to relocate any CIED. Clinically relevant events are uncommon, so it remains debatable which procedure is necessary. Daily controls could be avoided in some selected cases without compromising patient safety.

Infraclavicular versus axillary nerve catheters: A retrospective comparison of early catheter failure rate.

STUDY OBJECTIVES: Continuous brachial plexus catheters are often used to decrease pain following elbow surgery. This investigation aimed to assess the rate of early failure of infraclavicular (IC) and axillary (AX) nerve catheters following elbow surgery. DESIGN: Retrospective study. SETTING: Postoperative recovery unit and inpatient hospital floor. PATIENTS: 328 patients who received IC or AX nerve catheters and underwent elbow surgery were identified by retrospective query of our institution's database. MEASUREMENTS: Data collected included unplanned catheter dislodgement, catheter replacement rate, postoperative pain scores, and opioid administration on postoperative day 1. Catheter failure was defined as unplanned dislodging within 24 h of placement or requirement for catheter replacement and evaluated using a covariate adjusted model. MAIN RESULTS: 119 IC catheters and 209 AX catheters were evaluated. There were 8 (6.7%) failed IC catheters versus 13 (6.2%) failed AX catheters. After adjusting for age, BMI, and gender there was no difference in catheter failure rate between IC and AX nerve catheters (p = 0.449). CONCLUSIONS: These results suggest that IC and AX nerve catheters do not differ in the rate of early catheter failure, despite differences in anatomic location and catheter placement techniques. Both techniques provided effective postoperative analgesia with median pain scores < 3/10 for patients following elbow surgery. Reasons other than rate of early catheter failure should dictate which approach is performed.

Quantitative Approach to Failure Mode and Effect Analysis for Linear Accelerator Quality Assurance.

PURPOSE: To determine clinic-specific linear accelerator quality assurance (QA) TG-142 test frequencies, to maximize physicist time efficiency and patient treatment quality. METHODS AND MATERIALS: A novel quantitative approach to failure mode and effect analysis is proposed. Nine linear accelerator-years of QA records provided data on failure occurrence rates. The severity of test failure was modeled by introducing corresponding errors into head and neck intensity modulated radiation therapy treatment plans. The relative risk of daily linear accelerator QA was calculated as a function of frequency of test performance. RESULTS: Although the failure severity was greatest for daily imaging QA (imaging vs treatment isocenter and imaging positioning/repositioning), the failure occurrence rate was greatest for output and laser testing. The composite ranking results suggest that performing output and lasers tests daily, imaging versus treatment isocenter and imaging positioning/repositioning tests weekly, and optical distance indicator and jaws versus light field tests biweekly would be acceptable for non-stereotactic radiosurgery/stereotactic body radiation therapy linear accelerators. CONCLUSIONS: Failure mode and effect analysis is a useful tool to determine the relative importance of QA tests from TG-142. Because there are practical time limitations on how many QA tests can be performed, this analysis highlights which tests are the most important and suggests the frequency of testing based on each test's risk priority number.

Adverse Events Involving Radiation Oncology Medical Devices: Comprehensive Analysis of US Food and Drug Administration Data, 1991 to 2015.

PURPOSE: Radiation oncology relies on rapidly evolving technology and highly complex processes. The US Food and Drug Administration collects reports of adverse events related to medical devices. We sought to characterize all events involving radiation oncology devices (RODs) from the US Food and Drug Administration's postmarket surveillance Manufacturer and User Facility Device Experience (MAUDE) database, comparing these with non-radiation oncology devices. METHODS AND MATERIALS: MAUDE data on RODs from 1991 to 2015 were sorted into 4 product categories (external beam, brachytherapy, planning systems, and simulation systems) and 5 device problem categories (software, mechanical, electrical, user error, and dose delivery impact). Outcomes included whether the device was evaluated by the manufacturer, adverse event type, remedial action, problem code, device age, and time since 510(k) approval. Descriptive statistics were performed with linear regression of time-series data. Results for RODs were compared with those for other devices by the Pearson χ2 test for categorical data and 2-sample Kolmogorov-Smirnov test for distributions. RESULTS: There were 4234 ROD and 4,985,698 other device adverse event reports. Adverse event reports increased over time, and events involving RODs peaked in 2011. Most ROD reports involved external beam therapy (50.8%), followed by brachytherapy (24.9%) and treatment planning systems (21.6%). The top problem types were software (30.4%), mechanical (20.9%), and user error (20.4%). RODs differed significantly from other devices in each outcome (P<.001). RODs were more likely to be evaluated by the manufacturer after an event (46.9% vs 33.0%) but less likely to be recalled (10.5% vs 37.9%) (P<.001). Device age and time since 510(k) approval were shorter among RODs (P<.001). CONCLUSIONS: Compared with other devices, RODs may experience adverse events sooner after manufacture and market approval. Close postmarket surveillance, improved software design, and manufacturer-user training may help mitigate these events.

A 5-year survival analysis of 160 Biomet Magnum M2 metal-on-metal total hip prostheses.

BACKGROUND: Large-head metal-on-metal (MoM) total hip arthroplasties (THA) are associated with high failure rates and possible pseudotumour formation. This study reports the first results of 160 Biomet Magnum M2 large-head MoM total hip articulations. PATIENTS AND METHODS: From 2006 to 2010 the Reinier de Graaf Hospital implanted 160 large-head Magnum M2 MoM THAs (Biomet Inc. Warsaw, Indiana, USA) in 150 patients. These patients were recalled after a warning from the Dutch Orthopaedic Association. Patients were offered a clinical and radiographic assessment of the hip prosthesis, serum control on cobalt and chromium ions, and an ultrasound of the hip. If indicated, additional MARS-MRI or CT scan was performed. Descriptive statistical analysis, correlations, t-tests, non-parametric tests and implant survival were calculated. RESULTS: The mean follow-up was 6.1 years (4.8-8.4). A cumulative survival rate of 93.1% (95% CI: 88.3-98%) was found after 5 years. Reasons for revision were loosening, pain, infection and pseudotumour formation. The prevalence of pseudotumour formation around the prostheses was 8.75%. CONCLUSIONS: This study reports the first results of 160 MoM THAs implanted in our clinic from 2006-2010. In total, 13 (8.1%) of the THAs were eligible for revision after the recall. In most patients the reason for revision was pseudotumour formation. A total of 14 (8.75%) pseudotumours were diagnosed at the first recall. These results show that a comprehensive follow-up strategy is essential for MoM THAs to promptly identify and manage early complications.

Clinical safety of England's national programme for IT: a retrospective analysis of all reported safety events 2005 to 2011.

OBJECTIVE: To analyse patient safety events associated with England's national programme for IT (NPfIT). METHODS: Retrospective analysis of all safety events managed by a dedicated IT safety team between September 2005 and November 2011 was undertaken. Events were reviewed against an existing classification for problems associated with IT. The proportion of reported events per problem type, consequences, source of report, resolution within 24h, time of day and day of week were examined. Sub-group analyses were undertaken for events involving patient harm and those that occurred on a large scale. RESULTS: Of the 850 events analysed, 68% (n=574) described potentially hazardous circumstances, 24% (n=205) had an observable impact on care delivery, 4% (n=36) were a near miss, and 3% (n=22) were associated with patient harm, including three deaths (0·35%). Eleven events did not have a noticeable consequence (1%) and two were complaints (<1%). Amongst the events 1606 separate contributing problems were identified. Of these 92% were predominately associated with technical rather than human factors. Problems involving human factors were four times as likely to result in patient harm than technical problems (25% versus 8%; OR 3·98, 95%CI 1·90-8.34). Large-scale events affecting 10 or more individuals or multiple IT systems accounted for 23% (n=191) of the sample and were significantly more likely to result in a near miss (6% versus 4%) or impact the delivery of care (39% versus 20%; p<0·001). CONCLUSION: Events associated with NPfIT reinforce that the use of IT does create hazardous circumstances and can lead to patient harm or death. Large-scale patient safety events have the potential to affect many patients and clinicians, and this suggests that addressing them should be a priority for all major IT implementations.

Are routine postoperative radiographs necessary during the first year after posterior spinal fusion for idiopathic scoliosis? A retrospective cohort analysis of implant failure and surgery revision rates.

BACKGROUND: Radiographs are routinely obtained at postoperative visits during the first year after posterior spinal fusion (PSF) for idiopathic scoliosis (IS). The goal of this study was to determine how often radiographic findings change postoperative care. METHODS: A total of 227 consecutive patients aged 10 to 21 years who underwent surgery for IS at our institution from 2004 to 2010 were identified. Charts were reviewed to determine the frequency of the following clinical symptoms during the first year after surgery: pain greater than expected, implant prominence, and sensory/motor disturbance. Radiographs were reviewed to identify implant failure and curve change. Logistic regression analysis was used to identify clinical symptoms associated with treatment deviation. RESULTS: During the first year after surgery, an average of 6 (range, 2 to 12) radiographs were obtained from patients during an average of 3 (range, 2 to 10) follow-up visits. Pain (14%) was the most common symptom. Neurologic symptoms (13%) and implant prominence (4%) were less common. Implant failure was identified in 4 subjects (2%), of which 3 required revision surgery. The incidence of revision surgery was 2.9/1000 radiographs (95% confidence interval, 0.6-8.3). Curve progression >5 degrees in the uninstrumented curve occurred in 2 patients (0.9%). Curve progression did not result in a change in treatment for any of the patients. Pain was the only clinical symptom associated with implant failure (P=0.0047). 169/227 patients did not have any symptoms and only one of these underwent revision surgery. The sensitivity of a clinical test, which uses the presence of pain to guide the need for radiographic evaluation and rule out implant failure, was 75%, specificity 87%, positive predictive value 10%, and negative predictive value 99.5%. CONCLUSIONS: After obtaining baseline postoperative radiographs, additional radiographs during the first year after surgery for IS may not be required in the absence of clinical symptoms. Reducing the number of radiographs taken during the first year after surgery for IS in patients without symptoms can reduce radiation exposure to patients and health care costs without affecting treatment. LEVEL OF EVIDENCE: Level II, Diagnostic Study.

Dual mobility in total hip arthroplasty.

Dual-mobility articulations have shown promising results. Postoperative instability remains the most common reason for revision of a total hip arthroplasty (THA). Dual-mobility cups have been shown to decrease the rate of dislocation in primary THA and have been used to treat and prevent instability in revision THA. Greater range of motion and a greater head-to-neck ratio and a greater jump distance are achieved, resulting in a lower risk of instability. Concerns with dual-mobility cups include wear and intraprosthetic dislocation. Specific design modifications have aimed to improve cup fixation and decrease polyethylene wear and the risks of intraprosthetic dislocation.

Prospective evaluation of cinefluoroscopy and chest radiography for Riata lead defects: implications for future lead screening.

INTRODUCTION: Lead insulation defects with externalization of the conductors exist in Riata defibrillator leads. Cinefluoroscopy is currently the gold standard to detect such defects. Prospective evaluation of alternative screening options such as chest radiography (CXR), which has been recommended by the FDA, is not well described. METHODS AND RESULTS: Patients with Riata leads underwent cinefluoroscopy, CXR, and device interrogation. Leads were classified as abnormal (clear cable separation), borderline, or normal by independent evaluation of cinefluoroscopy and CXR. CXR evaluation was done in two ways as follows: (1) routine CXR read by daily staff radiologists for lead screening and (2) CXR evaluation by a radiologist educated about the lead defect. One hundred two patients were evaluated at our institution. Cinefluoroscopy showed externalized conductors in 33 patients (32 %). Twenty-five of 33 patients (76 %) who had abnormal cinefluoroscopic findings had abnormal CXR findings on blinded review by the educated radiologist. All 25 patients with abnormal CXR had abnormal findings on cinefluoroscopy. Daily staff radiologists without direct education other than prompts for lead screening detected CXR abnormalities in only 8 out of 102 (8 %) cases. CONCLUSION: Cinefluoroscopy appears to be more sensitive than CXR for the detection of Riata cable extrusion. Interpretation of CXR by a radiologist with education in lead defects correlates highly with cinefluoroscopy with very high specificity. Depending on available resources for screening, CXR may be a reasonable alternative to cinefluoroscopy. Multidisciplinary collaboration across specialties (radiology and electrophysiology) can lead to improved diagnostic capability and thus the potential for enhanced quality of care.