The receptor-like kinase ARK controls symbiotic balance across land plants.

The mutualistic arbuscular mycorrhizal (AM) symbiosis arose in land plants more than 450 million years ago and is still widely found in all major land plant lineages. Despite its broad taxonomic distribution, little is known about the molecular components underpinning symbiosis outside of flowering plants. The ARBUSCULAR RECEPTOR-LIKE KINASE (ARK) is required for sustaining AM symbiosis in distantly related angiosperms. Here, we demonstrate that ARK has an equivalent role in symbiosis maintenance in the bryophyte Marchantia paleacea and is part of a broad AM genetic program conserved among land plants. In addition, our comparative transcriptome analysis identified evolutionarily conserved expression patterns for several genes in the core symbiotic program required for presymbiotic signaling, intracellular colonization, and nutrient exchange. This study provides insights into the molecular pathways that consistently associate with AM symbiosis across land plants and identifies an ancestral role for ARK in governing symbiotic balance.

Inequity of healthcare access for patients with diabetic foot disease: a retrospective study in south-east Queensland.

OBJECTIVES: Logan local government area (LGA) in Queensland has the highest diabetes prevalence (6.5%) within Metro South Health (MSH). The study aimed to determine the burden of, and equity of access to secondary healthcare, for diabetic foot disease (DFD) for Logan residents to better inform healthcare services planning. DESIGN: A retrospective analysis of hospital admissions data between January 2018 and December 2021. SETTING, PARTICIPANTS: All episodes of care for DFD provided by MSH hospitals to patients with a residential address in the three LGAs serving the region were included. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was number of episodes of care for DFD by LGA of residence and hospital of presentation. Secondary outcomes were DFD-related hospital occupied bed days and number of lower extremity amputations. RESULTS: Among residents in the MSH region, almost half of all episodes of care (47%) and bed days (48%) for DFD were for patients residing in Logan LGA. 40% of episodes of care, 57% of bed days and 73% of lower extremity amputations for DFD for these patients occurred outside of Logan LGA. These findings led to the planning of an integrated model of care for DFD at Logan hospital to improve and make care available locally. CONCLUSIONS: Our study suggests that Logan residents with DFD had poor access to care despite the highest burden. Analysing epidemiology of care for DFD with an equity lens and highlighting gaps in service delivery is paramount to addressing the inequity paradigm.

Costs and 30-day readmission after lower limb fractures from motorcycle crashes in Queensland, Australia: A linked data analysis.

BACKGROUND: Lower limb trauma is the most common injury sustained in motorcycle crashes. There are limited data describing this cohort in Australia and limited international data establishing costs due to lower limb trauma following motorcycle crashes. METHODS: This retrospective cohort study utilised administrative hospitalisation data from Queensland, Australia from 2011-2017. Eligible participants included those admitted with a principal diagnosis coded as lower extremity or pelvic fracture following a motorcycle crash (defined as the index admission). Multiply injured motorcyclists where the lower limb injury was not coded as the primary diagnosis (i.e. principal diagnosis was rather coded as head injury, internal organ injures etc.) were not included in the study. Hospitalisation data were also linked to clinical costing data. Logistic regression was used to determine risk factors for 30-day readmission. Costing data were compared between those readmitted and those who weren't, using bootstrapped t-tests and ANVOA. RESULTS: A total of 3342 patients met eligibility, with the most common lower limb fracture being tibia/fibula fractures (40.8%). 212 participants (6.3%) were readmitted within 30-days of discharge. The following were found to predict readmission: male sex (OR 1.84, 95% CI 1.01-1.94); chronic anaemia (OR 2.19, 95% CI 1.41-3.39); current/ex-smoker (OR 1.60, 95% CI 1.21-2.12); emergency admission (OR 2.77, 95% CI 1.35-5.70) and tibia/fibula fracture type (OR 1.46, 95% CI 1.10-1.94). The most common reasons for readmission were related to ongoing fracture care, infection or post-operative complications. The average hospitalisation cost for the index admission was AU$29,044 (95% CI $27,235-$30,853) with significant differences seen between fracture types. The total hospitalisation cost of readmissions was almost AU$2 million over the study period, with an average cost of $10,977 (95% CI $9,131- $13,059). CONCLUSIONS: Unplanned readmissions occur in 6.3% of lower limb fractures sustained in motorcycle crashes. Independent predictors of readmission within 30 days of discharge included male sex, chronic anaemia, smoking status, fracture type and emergency admission. Index admission and readmission hospitalisation costs are substantial and should prompt health services to invest in ways to reduce readmission.

Ankle fracture management using smartphone multimedia messaging service (MMS) imaging - How reliable and to what point?

BACKGROUND: The use of smartphones and multimedia messaging service (MMS) continues to increase in day to day orthopaedic clinical practice. However, there is limited evidence to support the safe utilisation of MMS. OBJECTIVES: The aim of this study was to correlate the performance of MMS imaging to picture archiving and communication systems (PACS) imaging within the setting of diagnosis and management of ankle fractures. METHODS: The ankle fracture radiograph series of 82 consecutive patients were evaluated by five orthopaedic consultant specialists. A questionnaire regarding diagnosis and preferred management was completed separately for each patient using smartphone and PACS images. Statistical analysis was performed using Intraclass Correlation Coefficient (ICC). RESULTS: Ankle fracture diagnosis showed strong to excellent correlation both inter- and intraobserver MMS vs PACS when using the Weber (0.815, 0.988), Anatomical (0.858, 0.988), and AO classification systems (0.855, 0.985). MMS was less reliable than PACS in determining many management options. CONCLUSION: The reliability of ankle fracture classification using MMS image viewing was not significantly different to interpretation on PACS workstations. Smartphone use in ankle fracture classification is supported by this study. Smartphone use was less accurate than PACS in devising management plans and future use should be limited to making only initial plans that must be corroberated with PACS and intraoperative findings prior to definitive fixation.

Turning Up the Temperature on CRISPR: Increased Temperature Can Improve the Editing Efficiency of Wheat Using CRISPR/Cas9.

The application of CRISPR/Cas9 technologies has transformed our ability to target and edit designated regions of a genome. It's broad adaptability to any organism has led to countless advancements in our understanding of many biological processes. Many current tools are designed for simple plant systems such as diploid species, however, efficient deployment in crop species requires a greater efficiency of editing as these often contain polyploid genomes. Here, we examined the role of temperature to understand if CRISPR/Cas9 editing efficiency can be improved in wheat. The recent finding that plant growth under higher temperatures could increase mutation rates was tested with Cas9 expressed from two different promoters in wheat. Increasing the temperature of the tissue culture or of the seed germination and early growth phase increases the frequency of mutation in wheat when the Cas9 enzyme is driven by the ZmUbi promoter but not OsActin. In contrast, Cas9 expression driven by the OsActin promoter did not increase the mutations detected in either transformed lines or during the transformation process itself. These results demonstrate that CRISPR/Cas9 editing efficiency can be significantly increased in a polyploid cereal species with a simple change in growth conditions to facilitate increased mutations for the creation of homozygous or null knock-outs.

Transarticular tibiotalocalcaneal nailing versus open reduction and internal fixation for treatment of the elderly ankle fracture: protocol for a multicentre, prospective, randomised controlled trial.

INTRODUCTION: Ankle fractures are common in the elderly population. Surgical fixation is technically challenging and often results in complications due to high rates of osteoporosis and vascular disease. Open reduction and internal fixation (ORIF) often requires prolonged periods of non-weight bearing increasing the risks of complications. Tibiotalocalcaneal (TTC) nailing has been suggested as an alternative to ORIF which allows immediate weight bearing, and is suggested to result in fewer complications. This study aims to compare the two surgical techniques in the elderly population with ankle fractures. METHODS AND ANALYSIS: The study will be a multicentre, prospective, randomised controlled trial comparing ORIF to TTC nailing in 110 patients with ankle fractures aged 50 or above with a Charlson Comorbidity Index of greater than or equal to four. Participants and assessors will not be blinded to intervention. The primary outcome measure will be overall complication rate. Secondary outcomes include length of hospital stay, mobility at discharge, discharge destination, the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot score, the Olerud-Molander Ankle Score, mortality rate, rate of secondary surgical interventions and number of blood transfusions required postoperatively. Our null hypothesis is that there is no clinically significant difference in the primary outcome measure between the two treatment groups. ETHICS AND DISSEMINATION: The study has been approved by Metro South Hospital and Health Services Human Research Ethics Committee (EC00167) (reference number HREC/17/QPAH/351). DISCUSSION: Completion of this trial will provide evidence on the effectiveness of TTC nailing versus ORIF in treatment of the elderly ankle fracture. If TTC nailing is found to result in superior outcomes, this trial has the capacity to change current clinical practice. TRIAL REGISTRATION NUMBER: ACTRN12617001588381;Pre-results andU1111-1203-1704.

Is it necessary to re-fuse a non-union of a Hallux metatarsophalangeal joint arthrodesis?

BACKGROUND: The standard treatment for a non-union of the hallux metatarsophalangeal joint fusion has been to revise the fusion. Revision fusion is technically more demanding, often involving bone grafting, more substantial fixation and prolonged period of immobilization postoperatively. We present data to suggest that removal of hardware and debridement alone is an alternative treatment option. MATERIALS AND METHODS: A case note review identified patients with a symptomatic non-union after hallux metatarsophalangeal joint (MTPJ) fusion. It is our practice to offer these patients revision fusion or removal of hardware and debridement. For the seven patients that chose hardware removal and were left with a pseudarthrosis, a matched control group was selected from patients who had had successful fusions. Three outcome scores were used. Hallux valgus and dorsiflexion angles were recorded. RESULTS: One hundred thirty-nine hallux MTPJ arthrodeses were carried out. Fourteen non-unions were identified. The rate of non-union in males and following previous hallux MTPJ surgery was 19% and 24%, respectively. In females undergoing a primary MTPJ fusion, the rate was 2.4%. Twelve non-union patients were reviewed at 27 months (mean). Eleven patients had elected to undergo removal of hardware and debridement. Four patients with pseudarthrosis were unhappy with the results and proceeded to either revision fusion or MTPJ replacement. Seven non-union patients, who had removal of hardware alone, had outcome scores marginally worse compared to those with successful fusions. CONCLUSION: Removal of hardware alone is a reasonable option to offer as a relatively minor procedure following a failed arthrodesis of the first MTPJ. This must be accepted on the proviso that in this study four out of 11 (36%) patients proceeded to a revision first MTPJ fusion or first MTPJ replacement. We also found that the rate of non-union in primary first MTPJ fusion was significantly higher in males and those patients who had undergone previous surgery.

Tendon healing.

An understanding of the processes of tendon healing and tendon-to-bone healing is important for the intraoperative and postoperative management of patients with tendon ruptures or of patients requiring tendon transfers in foot and ankle surgery. Knowledge of the normal process allows clinicians to develop strategies when normal healing fails. This article reviews the important work behind the identification of the normal phases and control of tendon healing. It outlines the failed response in tendinopathy and describes tendon-to-bone healing in view of its importance in foot and ankle surgery.