Patho-morphology of patellar instability in children and adolescents: A systematic review and meta-analysis

BACKGROUND

Children and adolescents have the highest incidence of patellar instability among the population. We aimed to identify patho-morphological and epidemiological factors associated with patellar instability, and to identify factors predisposing to recurrence in children and adolescents.

METHODS

Published and unpublished literature databases, conference proceedings and the reference lists of included studies were searched to the 14th of March 2024. Studies were eligible if they compared history characteristics, examination features and radiological parameters between patients with and without instability, or evaluated risk factors for instability recurrence. A random-effects meta-analysis was performed. Included studies were appraised using tools respective of study design.

RESULTS

The evidence was moderate to low in quality. Forty-five studies (including 9000 patients) were eligible. Tibial tubercle - tibial groove (TT-TG) distance (weighted mean difference [WMD] 5.96 mm, 95% Confidence Interval [CI]: 4.94 to 6.99 mm), sulcus angle (WMD: 13.93˚, 95% CI: 9.1˚ to 18.8˚), and Insall-Salvati index (WMD: 0.2, 95% CI: 0.16 to 0.23) were greater in patients with patellar instability. Risk factors for recurrent dislocation included age less than 18 years (Odds ratio [OR]: 2.56, 95% CI: 1.63 to 4.0), skeletal immaturity (OR: 1.79, 95% CI: 1.21 to 2.64) and presence of trochlear dysplasia (OR: 3.37, 95% CI: 1.85 to 6.15).

CONCLUSION

Knowledge of patho-morphological factors associated with patellar instability could help explain its pathophysiological processes, allowing for the design of treatment approaches and the identification of patients at risk.

Future research priorities for soft-tissue knee injuries

Aims

To identify unanswered questions about the prevention, diagnosis, treatment, and rehabilitation and delivery of care of first-time soft-tissue knee injuries (ligament injuries, patella dislocations, meniscal injuries, and articular cartilage) in children (aged 12 years and older) and adults.

Methods

The James Lind Alliance (JLA) methodology for Priority Setting Partnerships was followed. An initial survey invited patients and healthcare professionals from the UK to submit any uncertainties regarding soft-tissue knee injury prevention, diagnosis, treatment, and rehabilitation and delivery of care. Over 1,000 questions were received. From these, 74 questions (identifying common concerns) were formulated and checked against the best available evidence. An interim survey was then conducted and 27 questions were taken forward to the final workshop, held in January 2023, where they were discussed, ranked, and scored in multiple rounds of prioritization. This was conducted by healthcare professionals, patients, and carers.

Results

The top ten included questions regarding prevention, diagnosis, treatment, and rehabilitation. The number one question was, 'How urgently do soft-tissue knee injuries need to be treated for the best outcome?'. This reflects the concerns of patients, carers, and the wider multidisciplinary team.

Conclusion

This validated process has generated ten important priorities for future soft-tissue knee injury research. These have been submitted to the National Institute for Health and Care Research. All 27 questions in the final workshop have been published on the JLA website.

The carbon footprint of arthroscopic procedures

INTRODUCTION

The healthcare sector contributes the equivalent of 4.4% of global net emissions to the climate carbon footprint; between 20% and 70% of healthcare waste originates from a hospital's operating theatre and up to 90% of waste is sent for costly and unneeded hazardous waste processing. This study aimed to quantify the amount and type of waste produced during an arthroscopic anterior cruciate ligament reconstruction (ACLR) and an arthroscopic rotator cuff repair (RCR), calculate the carbon footprint and assess the cost of the waste disposal.

METHODS

The amount of waste generated from ACLR and RCR procedures was calculated across a range of hospital sites. The waste was separated primarily into clean and contaminated, paper or plastic. Both carbon footprint and cost of disposal across the hospital sites was subsequently calculated.

RESULTS

RCR generated 3.3-15.5kg of plastic waste and 0.9-2.3kg of paper waste. ACLR generated 2.4-9.6kg of plastic waste and 1.1-1.6kg of paper waste. The cost to process waste varies widely between hospital sites, waste disposal contractors and method of waste disposal. The annual burden of the included hospital sites for the arthroscopic procedures undertaken was 6.2 tonnes of carbon dioxide.

CONCLUSIONS

The data collected demonstrated a significant variability in waste production and cost for waste disposal between hospital sites. At a national level, consideration should be given to the procurement of appropriate products such that waste can be efficiently recycled or disposed of by environmentally sustainable methods.

Functional Walker Boots are Preferred to Synthetic Casts by Patients and Carers in the Management of Pediatric Stable Ankle Injuries

INTRODUCTION

Traditionally children who presented with a stable ankle injury have been managed in a below-knee synthetic cast. No previous study has investigated patient and parents/carer preference between synthetic casts and walker boots.

METHODS

Children aged between 6 and 16 years who presented with stable ankle injuries (ankle sprains, small fragment avulsions, and fibular Salter-Harris 1 injuries) were randomized to receive treatment with either a synthetic cast or a walker boot. A tailored, study-specific questionnaire was designed and completed at 4 weeks from injury to evaluate both patient and parents/carer preference. An analysis of costs associated with both treatments was performed.

RESULTS

Ninety-one patients were available for final analysis. Forty-seven received synthetic cast treatment and 44 walker boot treatment. Patient demographics and injury types were matched between groups.Statistical significance was found in favor of the walker boot with regard to comfort, reduction in activity during treatment, and patient-reported problems at the end of treatment. There was a strong and significant preference toward treatment with the walker boot, both from patients and parents/carers. There was no difference between groups with regard to walking ability, analgesia requirement, and patient-reported pain scores.Unplanned attendances to the hospital during the treatment period were higher in the synthetic cast group. The overall treatment cost per patient was lower with the walker boot.

CONCLUSIONS

In children who present with stable ankle injuries, treatment in a walker boot is preferred by both patients and parents/carers. It results in fewer unplanned attendances to the hospital, is less expensive, and we recommend it as the treatment of choice in stable pediatric ankle injuries.

LEVEL OF EVIDENCE

Level II.

Analysis of Growth After Transphyseal Anterior Cruciate Ligament Reconstruction in Children

BACKGROUND

Pediatric transphyseal anterior cruciate ligament reconstruction (ACLR) bears several advantages and is widely used. The main concern is the risk of growth disturbance. Our purpose was to investigate the incidence and risk factors of growth disturbance in skeletally immature patients who underwent transphyseal ACLR. We hypothesized that this procedure would generate neither clinically relevant limb length discrepancy (LLD) nor axis deviation.

METHODS

This prospective, consecutive, single-center series included skeletally immature patients who underwent primary transphyseal ACLR using semitendinosus tendon autograft, with a 2-year follow-up bone length standing radiograph of both lower limbs from pelvis to ankle in anterior posterior view. Lower limb length, mechanical axis deviation (MAD), lateral distal femoral angle (LDFA), and medial proximal tibial angle (MPTA) were measured. The definition of postoperative growth disturbance was defined as ≥10 mm for LLD or ≥3 degrees for axis deviation in comparison to the contralateral lower limb. Predictive variables included age at surgery, gender, side, and diameter of bone tunnels. Student or Mann-Whitney test was used for numerical variables, and Chi-square test or Fisher exact test was used for categorical variables. P values <0.05 were considered statistically significant.

RESULTS

Fifty consecutively treated patients were included. Forty-seven patients (31 boys, 16 girls) with a mean age of 13.2 years (range, 9 to 16) at the time of surgery were available for analysis. Six patients had an LLD of at least 10 mm. Twenty-five patients had a difference in MPTA of a least 3 degrees (range, 5 to 8). Sixteen patients had a difference in LDFA of a least 3 degrees (range, 4 to 9). No patients presented with a clinical deformity or related symptoms. Regarding coronal alignment, there was no statistical difference in mechanical axis deviation, LDFA, or MPTA. Gender, side, age, and bone tunnel diameter did not influence growth disturbance.

CONCLUSIONS

Transphyseal pediatric ACLR generated a high rate of growth disturbances (leg length discrepancy and axis deviation) although none clinically relevant. Mild proximal tibial axis deviation in patients operated on near skeletal maturity should be further investigated.

LEVEL OF EVIDENCE

Level III.

STUDY DESIGN

Case-control study.

Surgical techniques in the management of pediatric anterior cruciate ligament tears: Current concepts

Background

Anterior cruciate ligament injury in the child and adolescent patient remains a controversial topic when considering management, especially regarding surgical choices. Treatment variations are seen not just when comparing different countries but also within nations. This arises partly as contemporary treatment is mostly inferred from the adult population who physiologically and in terms of outcomes differ significantly from children. There is an increasing body of evidence for this cohort of patients who have specific challenges and difficulties when determining the optimum treatment.

Methods

Within this article, we will summarize the current evidence for surgical management of anterior cruciate ligament injury for the pediatric patient.

Results and Conclusions

There remain many controversies and gaps inthe treatment of Paediatric Anterior cruciate ligament reconstruction and this high risk cohort continues to cause difficulty in identifying the best mode of surgical management.

Level of evidence

level IV.

Osteochondritis dissecans of the knee: Epidemiology, etiology, and natural history

Osteochondritis dissecans of the knee is a disease that typically affects skeletally immature patients. Clinically manifested with knee pain, limping, and joint disfunction, this condition has remained misunderstood and undervalued for a long period. Although being a rare condition, its awareness is of utmost clinical interest because of the possible severe consequences it can bring when misrecognized or inadequately treated. Its etiology remains unclear and is still debated. Many theories have been proposed, including inflammation, local ischemia, subchondral ossification abnormalities, genetic factors, and repetitive mechanical microtrauma, with a likely interplay of the same. This review article aims to deliver and discuss current and up-to-date concepts on epidemiology, etiology, and natural history of this pediatric condition. Level of evidence: level V.

Current concepts in the treatment of first-time patella dislocation in children and adolescents

Background

Lateral dislocation of the patella is a common injury in children. It can occur in previously healthy and anatomically normal knees, but there are several abnormalities that predispose to patellar instability. Magnetic resonance imaging is an essential part of assessing for associated injuries and risk of further instability. Treatment aims to prevent redislocation, residual instability, osteoarthritis, and allow return to previous activities. The purpose of this review was to assess evidence for management of first-time patella dislocation in children and adolescents.

Methods

Literature review was performed, accompanied by the current best practice by the authors.

Results

Non-operative treatment is preferred, except where there are associated injuries such as osteochondral fractures that would benefit from surgery. The exact method of ideal non-operative management is not clearly defined but should focus on restoration of range of movement and strength with bracing as indicated. There seems to be a trend toward operative intervention that may well be inappropriate.

Conclusion

Further prospective studies are required with focus on the younger patient to fully understand if there is an at-risk group that would benefit from early surgery.

Level of evidence

level III.

How Much Does Paediatric Femoral Lengthening Cost? A Cost Comparison between Magnetic Lengthening Nails and External Fixators

Aim

Motorised intramedullary lengthening nails are considered more expensive than external fixators for limb lengthening. This research aims to compare the cost of femoral lengthening in children using the PRECICE magnetic lengthening nail with external fixation.

Methods

Retrospective analysis of 50 children who underwent femoral lengthening. One group included patients who were treated with PRECICE lengthening nails, the other group included patients who had lengthening with external fixation. Each group included 25 patients aged between 11 and 17 years. The patients in both groups were matched for age. Cost analysis was performed following micro-costing and analysis of the used resources during the different phases of the treatments.

Results

Each group's mean patient age was 14.7 years. Lengthening nails were associated with longer operative times compared with external fixators, both for implantation and removal surgery (p-values of 0.007 and < 0.0001, respectively). Length of stay following the implantation surgery, frequency of radiographs and frequency of outpatient department appointments were all lower with lengthening nails. The overall cost of lengthening nails was £1393 more than external fixators, however, this difference was not statistically significant (p-value = 0.088).

Conclusion

The difference in the mean costs between femoral lengthening with lengthening nails versus external fixators was not statistically significant. Further research to review the effectiveness of the devices and the quality of life during the lengthening process is crucial for robust health economic evaluation.

How to cite this article

Hafez M, Nicolaou N, Offiah A, et al. How Much Does Paediatric Femoral Lengthening Cost? A Cost Comparison between Magnetic Lengthening Nails and External Fixators. Strategies Trauma Limb Reconstr 2023;18(1):16-20.

Total, sex and age-specific excess mortality during 2020 in 20 countries part of the C-MOR consortium

 

Nationally published COVID-19 mortality estimates might underestimate the actual mortality burden attributed to COVID-19. Estimations of excess all-cause mortality can provide more accurate estimates of the toll of the pandemic. This study aims to estimate the overall, sex and age-specific excess all-cause mortality in 20 countries, during 2020. Total, sex and age-specific weekly all-cause death counts for 2015-2020 were extracted from national vital statistics databases. Percent excess mortality for 2020 was calculated by comparing average weekly 2020 mortality rates against average weekly mortality rates from the past five years (2015-2019). Comparisons were performed for the total population, per sex, and per age groups (<65 vs. 65+ or < 70 vs.70+) depending on data availability. Percent difference in average weekly mortality between 2020 and 2015-2019 ranged from negative for Australia and Norway, to < 5% for Denmark, Cyprus, Estonia, Israel, and Sweden, 5-10% for Georgia, Mauritius, Ukraine, Austria, France, Scotland and Northern Ireland, to ∼10-21% for England & Wales, Italy, Brazil, USA, Slovenia, and to 89% for Peru. The percent difference in average weekly mortality between 2020 and 2015-2019 for males was higher than for females except for Cyprus, Estonia, Slovenia and the USA. Lastly, in age specific analyses, for the majority of countries the % increase in average weekly mortality between 2020 and 2015-2019, was higher in the oldest age group investigated, however, for Peru and the USA (<65 vs. 65+ years) and for Cyprus and Mauritius (<70 vs. 70+ years), mortality increased similarly in both age groups. This study highlights that the excess mortality burden during the COVID-19 pandemic disproportionally affected specific countries, males, and in most, but not all countries, the oldest age groups. Strengthening of health resilience in the most affected countries, while targeting population groups impacted the most, is of paramount public health importance.

Key messages

• Excess mortality burden during the COVID-19 pandemic disproportionally affected specific countries, and even within countries specific sex and age groups.

• Further investigation into the determinants of excess mortality is needed to suggest steps to strengthen health resilience in the countries and target population groups impacted the most.

Quality of life of children during distraction osteogenesis: a comparison between intramedullary magnetic lengthening nails and external fixators

Background

Distraction osteogenesis is a very demanding process. For decades, external fixation was the only reliable option for gradual deformity correction. Recently, intramedullary magnetic nails have gained popularity. This research aimed to assess the quality of life in children during gradual deformity correction using intramedullary lengthening nails compared to external fixation.

Method

Prospective analysis included children who had gradual lower limb deformity correction between 2017 and 2019. Group A included children who had magnetic lengthening nails; patients in group B had external fixation devices. Child health utility 9D (CHU- 9D) and EuroQol 5D youth (EQ- 5D-Y) were used to measure the quality of life at fixed points during the distraction osteogenesis process. The results were used to calculate the utility at each milestone and the overall quality of life adjusted years (QALYs).

Results

Thirty-four children were recruited, group A had 16 patients, whilst group B had 18 patients. The average ages were 16.0 years and 14.7 years for groups A and B, respectively. Group A patients reported significantly better utility compared to group B. This was observed during all stages of treatment (P = 0.00016). QALYs were better for group A (0.44) compared to group B (0.34) (P < 0.0001).

Conclusion

The quality of life was generally better in group A compared to group B. In most patients, the health utility progressively improved throughout treatment. In the same way, QALYs were better with the lengthening nails compared to external fixators. The magnetic lengthening devices (PRECICE nails) which were used in this research were recently relabelled to restrict their applications in children; this study was conducted before these restrictions.

Femoral Lengthening in Children-A Comparison Between Magnetic Intramedullary Lengthening Nails and External Fixators

BACKGROUND

Femoral lengthening can be achieved using external fixators or intramedullary lengthening nails. The purpose of this research was to compare the outcome of femoral lengthening in children using PRECICE magnetic lengthening nails with lengthening external fixators.

METHODS

Retrospective analysis of 50 children who had femoral lengthening. Group A included patients who had lengthening with external fixation, patients in Group B had lengthening with PRECICE intramedullary lengthening nails. Each group included 25 patients. The sample strictly included children aged between 11 and 17 years. Patients in each group were matched according to age and indication for lengthening whether congenital or acquired conditions. The outcomes focused on the ability to achieve target length, healing index, residual malalignment, length of hospitalization following the osteotomy surgery, and encountered complications.

RESULTS

Mean patient age was 14.7 years for each group. The length gain was 42±12 mm for Group A and 41.6±8 mm for Group B (P=0.84). Lengthening nails achieved the target length more accurately compared with external fixation (P=0.017). The healing index was significantly higher in group A with 53.2±19 days/cm compared with 40.2±14 days/cm in group B (P=0.03). Group A had significantly higher complications than group B (P<0.0001). There was no statistically significant difference in the final coronal malalignment between the 2 groups (P=0.2). The mean length of stay was 9.2±5.8 days for group A and 4.2±3.3 days for group B (P=0.0005).

CONCLUSION

Magnetic lengthening nails are clinically effective for femoral lengthening in the pediatric population. Compared with external fixation, healing index and complications were more favorable with PRECICE nails. Further research is required to study the cost-effectiveness of this technique.

LEVEL OF EVIDENCE

Level IV-case series.

High bone mass phenotype in a cohort of patients with Osteogenesis Imperfecta caused due to BMP1 and C-propeptide cleavage variants in COL1A1

OBJECTIVES

Osteogenesis Imperfecta (OI) is a heterogeneous condition mainly characterised by bone fragility; extra-skeletal features in OI include blue sclerae, dentinogenesis imperfecta, skin laxity and joint hyper-extensibility. Most patients with OI are thought to have a low bone mass but contrary to expectations there are certain forms of OI with high bone mass which this study explores in further detail.

METHOD

A cohort of n = 6 individuals with pathogenic variants in BMP1 and the C-propeptide cleavage variants in COL1A1 were included in this study. Detailed clinical and radiological phenotyping was done and correlated with genotype to identify patterns of clinical presentation and fracture history in this cohort of patients. This data was compared to previously reported literature in this group.

RESULTS

2 patients with BMP1 and 4 patients with pathogenic variants in C-propeptide region in COL1A1 were deep-phenotyped as part of this study and 1 patient with C-propeptide variant in COL1A1, showed low bone mineral density. In those with an elevated bone mineral density, this became even more apparent on bisphosphonate therapy. Patients in this cohort had variable clinical presentation ranging from antenatal presentation to more of an insidious course resulting in later confirmation of genetic diagnosis up to 19 years of age.

CONCLUSIONS

Patients with pathogenic variants in the C-propeptide region of COL1A1/A2 and BMP1 appear to have a high bone mass phenotype with increased sensitivity to bisphosphonate therapy. It is important to closely monitor patients with these genotypes to assess their response to therapy and tailor their treatment regime accordingly.

Femoral lengthening in young patients: An evidence-based comparison between motorized lengthening nails and external fixation

BACKGROUND

Femoral lengthening is a procedure of great importance in the treatment of congenital and acquired limb deficiencies. Technological advances have led to the latest designs of fully implantable motorized intramedullary lengthening nails. The use of these nails has increased over the last few years.

AIM

To review and critically appraise the literature comparing the outcome of femoral lengthening in children using intramedullary motorized lengthening nails to external fixation.

METHODS

Electronic databases (MEDLINE, CINAHL, EMBASE, Cochrane) were systematically searched in November 2019 for studies comparing the outcome of femoral lengthening in children using magnetic lengthening nails and external fixation. The outcomes included amount of gained length, healing index, complications and patient reported outcomes.

RESULTS

Of the 452 identified studies, only two (retrospective and non-randomized) met the inclusion criteria. A total of 91 femora were included. In both studies, the age of patients treated with nails ranged from 15 to 21 years compared to 9 to 15 years for patients in the external fixation group. Both devices achieved the target length. Prevalence of adverse events was less in the nail (60%-73%) than in the external fixation (81%-100%) group. None of the studies presented patient reported outcomes.

CONCLUSION

The clinical effectiveness of motorized nails is equivalent or superior to external fixation for femoral lengthening in young patients. The available literature is limited and does not provide evidence on patient quality of life or cost effectiveness of the interventions.

Outcomes of distally un-threaded screw fixation of slipped capital femoral epiphysis at skeletal maturity: a matched cohort study

The most common treatment for slipped capital femoral epiphysis worldwide is in situ fixation with a threaded screw. Un-threaded screws are designed to prevent slip progression without hindering residual growth of the proximal femur. This study aimed to compare growth, remodelling and long-term outcomes after fixation with un-threaded screws and a matched cohort of patients treated with a standard screw. Six patients (nine hips) treated with un-threaded screws and 16 patients (21 hips) treated with standard screws matched for age, skeletal maturity, sex and Southwick angle were recruited. Clinical records were reviewed for patient demographics, medical history and complications. Radiographs were reviewed for residual growth and time to physeal closure. Growth velocity was calculated. Absence of cam deformity signified complete remodelling. Clinical assessment was graded from excellent to poor and patient-reported outcomes were recorded. There was significantly more growth recorded in the un-threaded screw group in femoral neck length (7.6 mm, P = 0.003), articulo-lesser trochanter distance (5.3 mm, P = 0.028), pin-joint ratio (7.439%, P = 0.006) and pin-physis ratio (8.244%, P = 0.001). The probability of revision operations due to ongoing growth was higher in this group (risk ratio: 6.57, P = 0.0008). Time to physeal closure was not significantly different, but growth velocity was significantly higher in the un-threaded group. The lower probability of cam deformity was not significant. Functional and clinical results were not significantly different at average 11.2 years' follow-up. Un-threaded screws allow for significantly more growth than standard threaded screws. The un-threaded screw could not be recommended due to the higher re-operation rates, without any proven benefit.

Potential life years lost to COVID-19 in 17 countries during the pandemic period, up to August 2020

Background

COVID-19 pandemic is affecting populations and regions in different ways. In this study, we assess the Potential Years of Life Lost (PYLL) to COVID-19 across different regions.

Methods

We used age-group and sex-specific weekly COVID-19 deaths (from January to August 2020) from national primary sources of 17 countries from the C-MOR consortium (Australia, Brazil, Cape Verde, Colombia, Cyprus, France, Georgia, Israel, Kazakhstan, Peru, Norway, England & Wales, Scotland, Slovenia, Sweden, Ukraine, and the United States). PYLL were calculated by summing up the numbers of deaths in each age group multiplied by the remaining years of life up to age 80. Age-standardized PYLL rates (per 100,000 population), using the World (WHO 2000-2025) Standard population as the reference population, were estimated to facilitate comparison across countries.

Results

Countries in South America displayed the highest PYLL rates (567-1,377 PYLL/100,000). Countries in Asia & Middle East (besides Kazakhstan), Australia, and some European countries (Georgia, Norway, and Slovenia) observed <50 PYLL/100,000. Furthermore, the male to female PYLL rate ratio was above one in all countries [1.3 (Ukraine) - 14.4 (Cyprus)], besides Georgia (ratio = 0.5).

Conclusions

South America, and males were found to be the most affected by COVID-19. Ongoing monitoring of the COVID-19 mortality impact is essential in order to assess health system performances, control measures, and identify vulnerable populations. Differences in mortality burden among populations will help public health officials in their efforts to minimize the COVID-19 mortality burden on a local, and on a global level.

Key messages

Up to August 2020, COVID-19 was a cause of premature mortality in all the participating countries, with South America and males to be more affected.

The timing of the pandemic, seasonal trends, the control measures enforced, and underlying social conditions are probable explanations for the differences observed among countries.

Excess all-cause mortality from January to August 2020: a temporal analysis in 20 countries

 

Analysis of all-cause mortality is an important tool to investigate the impact of the COVID-19 pandemic. This study aims to investigate the magnitude and potential determinants of excess all-cause mortality, from January until August 2020, using national mortality databases from 20 countries part of the C-MOR consortium. Excess weekly mortality for 2020 was calculated by comparing observed against expected weekly number of deaths for 2020. Expected 2020 weekly mortality was estimated using 2015-19 data based on a time series model adjusting for time trend and seasonality. The excess mortality was visualized against a stringency index (SI), based on nine government response indicators, downloaded from the Oxford COVID-19 Government Response Tracker. Brazil, Cyprus, France, Ireland, Italy, countries of the UK, Spain and the USA showed a substantial increase in the observed mortality during 2020, which lasted from 1 (Cyprus) to 7 (England and Wales, Scotland) weeks. Australia, Denmark and Georgia observed fewer than expected deaths, whereas in Austria, Estonia, Israel, Norway, Slovenia and Ukraine 2020 mortality was as expected. Italy, Spain, UK and Brazil enforced high SI measures at least after 3 weeks from the first COVID-19 death. Sweden and the USA did not apply high SI measures for the duration of this study. In Austria, Estonia, Israel, Norway, Cyprus, Georgia, Slovenia and Ukraine, measures of high SI were implemented within 2 weeks of the first COVID-19 death. The decreased mortality in Australia is probably attributed to different seasonality patterns coupled with strict control measures. Several but not all countries showed excess all-cause mortality. Excess mortality was shown to be influenced by the seasonality patterns of each country, as well as the promptness of governments to apply high SI control measures. As the pandemic continues, the lessons learned from the first months of the pandemic can prove useful to minimize increases in all-cause mortality.

Key messages

Some countries showed excess all-cause mortality between January and August 2020, whereas others displayed either negligible excess mortality or even a decrease in all-cause mortality.

Excess mortality may be partly attributed to delayed application of strict control measures whereas lack of excess mortality may be due to seasonality and/or strict control measures.

Mechanical Analysis of Explanted Telescopic Rods in the Management of Osteogenesis Imperfecta: A Multicenter Study

BACKGROUND

Telescopic rods in the management of osteogenesis imperfecta fail frequently. This could be attributed to technical errors, rod design, and rod structure. We aimed to analyze the mechanical properties and tribology of explanted male and female components to identify effects of in vivo telescoping that may relate to observed patterns of successful telescoping or failure.

METHODS

Recruitment took place at 3 of the 4 English centers for osteogenesis imperfecta. Twenty-five rods explanted for growth or failure during revision to a new rod were analyzed in terms of clinical indication and prerevision imaging to identify if there was a technical mode of failure. Laboratory analysis was performed using optical and scanning electrical microscopy, radiograph diffraction analysis, hardness test, bending test, and energy-dispersive x-ray spectroscopy.

RESULTS

All implants tested were of high-grade stainless steel. Female components had inferior strength [mean Vickers hardness property (HV0.3) at 0.3 to 313 kg] in comparison to male components (HV0.3 406) due to different techniques of manufacture. Female rods also had a higher wear coefficient (7.89×10-12 m3/N/m3) than the male rods (6.46×10-12 m3/N/m3). Abrasive wear, shear deformation, scratches, and wear debris were identified in all rods. Male and female components displayed corrosion contributing to adhesive wear. Intraoperatively cut rods, particularly the female components, had irregular ends leading to more wear.

CONCLUSIONS

Current manufacturing techniques result in inferior material strength in female components compared with males, which combined with wear patterns is likely to lead to implant failure. Intraoperative cutting of rods may increase risk of failure due to wear. Considering techniques to improve strength as well as design in new implants may lead to better outcomes.

LEVELS OF EVIDENCE

Level IV-cross-sectional study.

The CoronaSurveys System for COVID-19 Incidence Data Collection and Processing

CoronaSurveys is an ongoing interdisciplinary project developing a system to infer the incidence of COVID-19 around the world using anonymous open surveys. The surveys have been translated into 60 languages and are continuously collecting participant responses from any country in the world. The responses collected are pre-processed, organized, and stored in a version-controlled repository, which is publicly available to the scientific community. In addition, the CoronaSurveys team has devised several estimates computed on the basis of survey responses and other data, and makes them available on the project’s website in the form of tables, as well as interactive plots and maps. In this paper, we describe the computational system developed for the CoronaSurveys project. The system includes multiple components and processes, including the web survey, the mobile apps, the cleaning and aggregation process of the survey responses, the process of storage and publication of the data, the processing of the data and the computation of estimates, and the visualization of the results. In this paper we describe the system architecture and the major challenges we faced in designing and deploying it.

Estimating the COVID-19 Prevalence in Spain With Indirect Reporting via Open Surveys

During the initial phases of the COVID-19 pandemic, accurate tracking has proven unfeasible. Initial estimation methods pointed toward case numbers that were much higher than officially reported. In the CoronaSurveys project, we have been addressing this issue using open online surveys with indirect reporting. We compare our estimates with the results of a serology study for Spain, obtaining high correlations (R squared 0.89). In our view, these results strongly support the idea of using open surveys with indirect reporting as a method to broadly sense the progress of a pandemic.

P09 Juvenile osteochondritis dissecans in juvenile idiopathic arthritis: a case series review

Background

Juvenile osteochondritis dissecans (JOCD) is a condition of bone and cartilage lesions. Contributory factors may include ischaemia, trauma, genetic or biomechanical factors such as abnormal joint loading. Children and young people (CYP) with juvenile idiopathic arthritis (JIA) have low physical activity levels, present with joint abnormalities and are exposed to immunosuppression including steroids which may cause reduced bone density. Here we describe JOCD in CYP with JIA in our service.

Methods

Retrospective reviews of case notes were conducted for current CYP with JIA in our service with known JOCD, detailing: JIA diagnosis Age & BMI at diagnosisSymptom duration pre-diagnosisManagement (including steroids)JOCD diagnosis Age & BMI at diagnosisImagingManagement

Results

Table 1 summarises the results. Twelve (n = 10 female) CYP in our cohort of 270 had JOCD with 20 lesions diagnosed on magnetic resonance imaging (MRI). Polyarticular (n = 4) and extended oligoarticular (n = 5) were the commonest JIA sub-types with all CYP receiving systemic therapy and 75% (n = 9) requiring more than one biologic.

Mean symptom duration before JIA diagnosis was 6 months (range: 1-24 months) with a mean age of 6.5 years (range: 1.5-13 years). Mean time to JOCD diagnosis was 5.5 years (range: 1.5-10.25 years) with a mean age of 12 years (range: 8-17 years) and 7 CYP having a high BMI (>85th percentile for age). The mean number of previous steroid injections per JOCD joint was 4 (range: 0-17) compared with 3 (range: 0-8) in the non-JOCD joint. Talar dome lesions (n = 9) were commonest, followed by femoral condyle (n = 4 medial, n = 3 lateral). Initial management was conservative, with half (n = 10) requiring surgery. P09 Table 1

Conclusion

This review identifies that 4% (n = 12/270) of our CYP with JIA have known JOCD, compared with 0.03% (n = 29/100,000) of the general population. Risk factors appear to be polyarticular disease, exposure to ≥ 4 steroid injections per joint, biologic-resistant disease and high BMI with low physical activity. Where CYP with JIA report symptoms which do not fit an inflammatory pattern there should be a low threshold to consider JOCD, with prospective research needed to better understand the relationship between JOCD and JIA.

Conflicts of Interest

The authors declare no conflicts of interest.

Formalizing and Implementing Distributed Ledger Objects

Despite the hype about blockchains and distributed ledgers, formal abstractions of these objects are scarce1. To face this issue, in this paper we provide a proper formulation of a distributed ledger object. In brief, we de ne a ledger object as a sequence of records, and we provide the operations and the properties that such an object should support. Implemen- tation of a ledger object on top of multiple (possibly geographically dispersed) computing devices gives rise to the distributed ledger object. In contrast to the centralized object, dis- tribution allows operations to be applied concurrently on the ledger, introducing challenges on the consistency of the ledger in each participant. We provide the de nitions of three well known consistency guarantees in terms of the operations supported by the ledger object: (1) atomic consistency (linearizability), (2) sequential consistency, and (3) eventual consistency. We then provide implementations of distributed ledgers on asynchronous message passing crash- prone systems using an Atomic Broadcast service, and show that they provide eventual, sequen- tial or atomic consistency semantics respectively. We conclude with a variation of the ledger the validated ledger which requires that each record in the ledger satis es a particular validation rule.

A consensus exercise identifying priorities for research into clinical effectiveness among children's orthopaedic surgeons in the United Kingdom

Aims

High-quality clinical research in children's orthopaedic surgery has lagged behind other surgical subspecialties. This study used a consensus-based approach to identify research priorities for clinical trials in children's orthopaedics.

Methods

A modified Delphi technique was used, which involved an initial scoping survey, a two-round Delphi process and an expert panel formed of members of the British Society of Children's Orthopaedic Surgery. The survey was conducted amongst orthopaedic surgeons treating children in the United Kingdom and Ireland.

Results

A total of 86 clinicians contributed to both rounds of the Delphi process, scoring priorities from one (low priority) to five (high priority). Elective topics were ranked higher than those relating to trauma, with the top ten elective research questions scoring higher than the top question for trauma. Ten elective, and five trauma research priorities were identified, with the three highest ranked questions relating to the treatment of slipped capital femoral epiphysis (mean score 4.6/ 5), Perthes' disease (4.5) and bone infection (4.5).

Conclusion

This consensus-based research agenda will guide surgeons, academics and funders to improve the evidence in children's orthopaedic surgery and encourage the development of multicentre clinical trials. Cite this article: Bone Joint J 2018;100-B:680-4.

Squamous carcinoma arising from a true tracheal bronchus: Management and case report

A case of a squamous carcinoma arising in a "True" tracheal bronchus is described. The presentation and management of this case is discussed.

Spatial Analytic Phase Difference of EEG activity during anesthetic-induced unconsciousness

OBJECTIVE

A number of studies provide supporting evidence for changes in synchronization during anesthetic-induced unconsciousness. This study investigates how anesthetic administration affects the widespread patterns of phase synchrony.

METHODS

The recently introduced method of Spatial Analytic Phase Difference (SAPD) was used to measure changes in synchrony in the electroencephalogram (EEG) activity of 29 patients undergoing routine surgery. Analysis was performed over 9 frequency bands: (i) δ (1.5-3.5Hz); (ii) θ (3.5-7.5Hz); (iii) α1 (8-10Hz); (iv) α2 (10.5-12Hz); (v) β1 (12.5-18Hz); (vi) β2 (18.5-21Hz); (vii) β3 (21.5-30Hz); (viii) γ1 (30.5-40Hz); and (ix) γ2 (60-80Hz).

RESULTS

Anesthesia was characterized by (a) large and localized synchrony increases in mid-frequency bands (8-12Hz), (b) smaller and widespread synchrony increases in higher frequency bands (30.5-40Hz, 60-80Hz), and (c) both increase and decrease of synchrony in low frequency bands (1.5-7.5Hz).

CONCLUSIONS

This study supports anesthetic-induced changes in synchrony, with the inducement of persistent and reversible widespread γ synchrony being most prominent.

SIGNIFICANCE

Our findings have implications in the study of consciousness, support existing literature in the field and contribute towards the theoretical understanding of the mechanisms behind loss of consciousness. Future investigations could result in a synchrony-based measure for monitoring the level of hypnosis of patients during surgery.

Global field synchrony during general anaesthesia

BACKGROUND

Anaesthetic agents may disrupt consciousness by inhibiting long-range synchronization of brain activity. In the current study, the patterns of widespread and spatially localized synchrony during anaesthesia are investigated using a measure called global field synchrony (GFS).

METHODS

The EEG obtained during routine surgery in 29 patients was analysed with GFS over the following frequency bands: δ (1.5-3.5 Hz), θ (3.5-7.5 Hz), α1 (8-10 Hz), α2 (10.5-12 Hz), β1 (12.5-18 Hz), β2 (18.5-21 Hz), β3 (21.5-30 Hz), γ1 (30.5-40 Hz), and γ2 (60-80 Hz). In addition, localized GFS estimations over aggregate brain areas were performed. GFS was estimated over 2 s non-overlapping windows. The differences in GFS values between 'wakefulness' and 'anaesthesia' were assessed with the two-sided Wilcoxon rank-sum tests (α=0.05).

RESULTS

Anaesthetic administration caused significant GFS changes in all frequency ranges and electrode combinations studied: (i) widespread synchrony increased in the α2 and β1 ranges and decreased in all other ranges, with the exception of α1 and β2, where no specific pattern was identified; and (ii) localized synchrony decreased in all areas in the δ and γ2 ranges, while location-specific changes were observed in the remaining frequency ranges. The most consistent findings were statistically significant decreases over all areas in the γ2 range, with GFS decrease over the central-right temporal being the most consistent change.

CONCLUSIONS

Significant frequency- and location-dependent changes in GFS were induced by anaesthetic administration, with more robust changes identified in the γ range. GFS can act as an aid for further and more detailed analysis regarding the particular combinations of frequency ranges and spatial locations that are most informative for the study of anaesthetic-induced unconsciousness.

Congenital pseudarthrosis of the tibia: the results of an evolving protocol of management

PURPOSE

This retrospective cohort study assesses the outcomes of a protocol of management, based on the recommendations of the European Paediatric Orthopaedic Society (EPOS) multi-centre study, for the management of congenital pseudarthrosis of the tibia.

METHODS

Utilising an incremental protocol of bracing, intramedullary rods and circular frame fixation with or without bone morphogenetic protein-2 (BMP-2), 11 patients had reached skeletal maturity or had follow up of 5 years from radiological union of the pseudarthrosis. Demographic data, deformity parameters before and after treatment, and functional outcome scores were recorded.

RESULTS

Ten of the 11 patients successfully healed and two sustained a refracture. All deformity parameters improved and a mean leg length discrepancy of 2.5 cm (range 0-7.5 cm) existed at the time of the last follow up. Some pseudarthroses healed with deformity correction and rod insertion alone. Six of the 11 patients had a confirmed diagnosis of neurofibromatosis and nine had sustained a fracture before 4 years of age. Refracture was associated with malalignment after healing.

CONCLUSION

This method of treatment provides a successful stepwise protocol for the management of this complex disorder, avoiding the use of aggressive limb reconstruction techniques at a young age in some cases. Level of evidenceCase series Level IV.

Giant atrial thrombus presenting as a tumor

INTRODUCTION

Right Atrial masses may represent tumors or thrombi of the heart and are potentially fatal if left untreated.

PRESENTATION OF CASE

A 45-year-old woman with a previous history of breast cancer who was found to have a right atrial mass diagnosed as a tumor by Echocardiography and Computed Tomography which ultimately proved to be a giant organized thrombus at surgery.

DISCUSSION

Metastatic tumors of the heart are 20 times more common than primary tumors and malignancies that often involve the heart include breast, lung, lymphoma, melanoma and sarcomas. Myxomas remain the most common cause of atrial tumors and are classically described arising on the left but a significant amount do occur on the right side. Presenting features with masses in the right atrium are similar to patients with tricuspid stenosis which may present with tiredeness, swelling of the feet, hepatomegaly and ascites. The clinical presentation and history may be of help in the diagnosis especially if the patient has a confirmed tumour.

CONCLUSION

Despite our current state of the art equipment these "masses" still pose a diagnostic challenge in distinguishing between solid thrombus and tumour as to determine the appropriate therapeutic approach. Surgical removal of Giant Atrial Thrombi appears to be the procedure of Choice.

Entropy measures for discrimination of 'awake' Vs 'anaesthetized' state in recovery from general anesthesia

Approximate Entropy (ApEn) and Permutation Entropy (PE) have been recently introduced for assessment of anesthetic depth. Both measures have previously been shown to track changes in the electrical brain activity related to the administration of anesthetic agents. In this paper ApEn and PE are compared for the automatic classification of 'awake' and 'anesthetized' state using a Support Vector Machine to assess their robustness for potential use in a device for monitoring awareness during general anesthesia. It was found that both measures provide linearly separable features and we are able to discriminate between the two states with accuracy greater than 96% using either of the two entropy measures.

Use of the Sheffield telescopic intramedullary rod system for the management of osteogenesis imperfecta: clinical outcomes at an average follow-up of nineteen years

BACKGROUND

Elongating intramedullary rods have been used in the management of osteogenesis imperfecta for the past fifty years. The complication rates reported in many reviews of the available techniques have been high. This study reviews the long-term functional outcomes and complications following the use of the Sheffield system of telescopic intramedullary rods.

METHODS

We conducted a retrospective analysis of patients with osteogenesis imperfecta who were at least eighteen years of age and who had at least thirteen years of follow-up. Complications, reoperations, and data from a disease-specific questionnaire and the Short Form-36 questionnaire were recorded.

RESULTS

Data for twenty-two patients with osteogenesis imperfecta who had been treated with Sheffield telescopic intramedullary rods were available at an average of nineteen years after the initial surgery. Reoperations involving thirty-three (50%) of the sixty-six rods were performed: ten rods (15%) were exchanged because of rod disengagement due to growth, thirteen rods (20%) were exchanged because of complications, and ten rods (15%) required further surgery other than exchange because of complications. Mobility was significantly improved at the initial postoperative visit (p = 0.0015), and this improvement was maintained into adulthood (p = 0.0077). Back pain was the most frequent symptom. Symptoms related to rod insertion across the knee and ankle were rare, but symptoms related to proximal femoral trochanteric entry were common. Physeal damage was not seen following surgery, and all rods elongated with growth. All patients were satisfied with the outcome of the surgical procedures. Short Form-36 scores for all physical domains and for social function and vitality were significantly worse than those in a normal population.

CONCLUSIONS

The outcomes of this technique are satisfactory in adulthood; reoperation rates are high but are most commonly related to the patient outgrowing the rods. Concerns regarding insertion of this fixed device at the knee and ankle were unfounded, although proximal femoral fixation remains a problem.

Fourier transform infrared spectroscopy and multivariate analysis for the detection and quantification of different milk species

The authenticity of milk and milk products is important and has extended health, cultural, and financial implications. Current analytical methods for the detection of milk adulteration are slow, laborious, and therefore impractical for use in routine milk screening by the dairy industry. Fourier transform infrared (FT-IR) spectroscopy is a rapid biochemical fingerprinting technique that could be used to reduce this sample analysis period significantly. To test this hypothesis we investigated 3 types of milk: cow, goat, and sheep milk. From these, 4 mixtures were prepared. The first 3 were binary mixtures of sheep and cow milk, goat and cow milk, or sheep and goat milk; in all mixtures the mixtures contained between 0 and 100% of each milk in increments of 5%. The fourth combination was a tertiary mixture containing sheep, cow, and goat milk also in increments of 5%. Analysis by FT-IR spectroscopy in combination with multivariate statistical methods, including partial least squares (PLS) regression and nonlinear kernel partial least squares (KPLS) regression, were used for multivariate calibration to quantify the different levels of adulterated milk. The FT-IR spectra showed a reasonably good predictive value for the binary mixtures, with an error level of 6.5 to 8% when analyzed using PLS. The results improved and excellent predictions were achieved (only 4-6% error) when KPLS was employed. Excellent predictions were achieved by both PLS and KPLS with errors of 3.4 to 4.9% and 3.9 to 6.4%, respectively, when the tertiary mixtures were analyzed. We believe that these results show that FT-IR spectroscopy has excellent potential for use in the dairy industry as a rapid method of detection and quantification in milk adulteration.

The use of permutation entropy to characterize sleep electroencephalograms

This work proposes the use of Permutation Entropy (PE), a measure of time-series complexity, to characterize electroencephalogram (EEG) signals recorded during sleep. Such a measure could provide information concerning the different sleep stages and, thus, be utilized as an additional aid to obtain sleep staging information. PE has been estimated for artifact-free 30s segments from more than 80 hours of EEG records obtained from 16 subjects during all-night recordings, from which the mean PE for each sleep stage was obtained. It was found that different sleep stages are characterized by significantly different PE values, which track the physiological changes in the complexity of the EEG signals observed at the different sleep stages. This finding encourages the use of PE as an additional aide to either visual or automated sleep staging.

Correlation between rotator cuff tears and repeated subacromial steroid injections: a case-controlled study

INTRODUCTION

Concern exists regarding potential damage to the rotator cuff from repeated corticosteroid injections into the subacromial space.

PATIENTS AND METHODS

In this retrospective, case-controlled study, 230 consecutive patients presenting to three orthopaedic units with subacromial impingement and investigated as an end-point with magnetic resonance imaging (MRI) of the shoulder were divided into groups having received less than three or three or more subacromial injections of corticosteroids.

RESULTS

With no significant difference in age and sex distribution, analysis by MRI showed no significant difference between the two groups in the incidence of rotator cuff tear (P < 1.0).

CONCLUSIONS

This suggests that corticosteroid use in patients with subacromial impingement should not be considered a causative factor in rotator cuff tears.