The position, orientation, and relative size of the fibularis longus tubercle in normal patients: A weightbearing CT assessment.

The fibularis longus attaches to the base of the first metatarsal at the fibularis/peroneus longus tubercle (FLT/PLT). Theoretically, differences in FLT morphology may reflect changes in the function of the fibularis longus. This study defines the normal limits of the FLT position, orientation, and size in patients with morphologically normal foot anatomy. A retrospective analysis of 131 feet without deformity in 72 patients undergoing weightbearing CT (WBCT) at a single center was conducted. The position and morphology of the FLT was assessed with novel measurements including tubercle-floor distance, tubercle-metatarsal angle, and the angle between the floor and a line bisecting the FLT (bisecting angle). Roundness of the FLT was compared to a triangle limiting its shape (triangular ratio), with lower values indicating increasing roundness. We also report relative size of the FLT to the first metatarsal (X/Y ratio), and relative size of the first metatarsal and FLT to the second metatarsal (XY/Z ratio). There were no significant side to side differences for any measurement (p > 0.05). Mean values were: tubercle-floor distance 28.02 ± 2.63 mm, tubercle-metatarsal angle 32.7 ± 6.32 degrees, bisecting angle 65.58 ± 6.27 degrees, triangular ratio 0.69 ± 0.04, X/Y ratio 1.13 ± 0.20, and XY/Z ratio 3.44 ± -0.72. Bisecting angle strongly correlated with tubercle-metatarsal angle (Pearson correlation 0.840, p < 0.001) suggesting FLT rotation occurred independent of foot position. ICC was >0.943 for all measurements. This study reports the morphology of the FLT in individuals with normal feet. This normative data may be used in future studies examining differences between groups of patients with foot pathology, helping us better understand the role of fibularis longus in the development and treatment of foot disorders.

Talar neck rotation angle in adults with clubfoot deformity: Observed values and intra- and inter-observer reliability using weightbearing CT.

INTRODUCTION: Adults presenting with symptomatic clubfoot represent a challenging cohort of patients. An appreciation of the location and degree of deformities is essential for management. Talar anatomy is often abnormal with varus within the talar neck, however, there are few reproducible methods which quantify talar neck deformity in adults. We describe a technique of assessing talar neck deformity, and report on observed values and intra- / inter-observer reliability. METHODS: This was a single-centre, retrospective study including 96 feet from 56 adult patients with clubfeet (82 feet had clubfoot deformity, 14 were normal). Mean age was 34.3 ± 16.9 years and 31 (55.3%) were male. Weight-bearing CT scans captured as part of routine clinical care were analysed. Image reformats were oriented parallel to the long axis of the talus in the sagittal plane. In the corresponding axial plane two lines were drawn (on separate slices): 1) a line perpendicular to the intermalleolar axis, 2) a line connecting the midpoints of the talar head and narrowest part of the talar neck. The talar neck rotation angle (TNR angle) was the angle formed between these lines. Intraclass correlation coefficients (ICC) were performed for intra- and inter-observer reliability. RESULTS: Mean TNR angle in clubfeet was 27.6 ± 12.2 degrees (95%CI = 25.0 to 30.2 degrees). Mean TNR angle in normal feet was 18.7 ± 5.1 degrees (95%CI = 16.0 to 21.4 degrees) (p < 0.001). The ICC for clubfeet was 0.944 (95%CI = 0.913 to 0.964) for intra-observer agreement, and 0.896 (95%CI = 0.837 to 0.932) for inter-observer agreement. CONCLUSION: This measurement technique demonstrated excellent intra- and inter-observer agreement. It also demonstrated that compared to normal feet, clubfeet had about 9 degrees of increased varus angulation of the talar neck. This technique and data may be used for future research into clubfoot deformity and in planning treatment. LEVEL OF CLINICAL EVIDENCE: 3.

The variation of anticoagulation prescribed in foot and ankle surgery in the UK - UK foot and ankle thrombo-embolism audit (UK-FATE).

INTRODUCTION: Venous thrombo-embolism (VTE) is a recognised complication of foot and ankle surgery. There are multiple possible anticoagulation treatments available in the UK to mitigate the risk of developing VTE. Our primary objective was to assess the variability of chemical anticoagulation prescribed in patients undergoing foot and ankle procedures. METHODS: This was a UK-based national, multicenter, prospective audit spanning a collection duration of 9 months on all foot and ankle procedures, carried out in 68 UK centers between 1st June 2022 and 30th November 2022, with a further 3-month follow up period. All patients who underwent a foot and ankle surgical procedure (including Achilles tendon rupture treatment) were included in this study. RESULTS: Data on a total of 13,569 patients was submitted. Following data cleansing, 11,363 patients were available for further analysis, with anticoagulation data available for 11,099 patients. There were eleven different chemical anticoagulation treatments recorded across the cohort. A total of 3630 (31.95 %) patients received no chemical anticoagulation. The patients receiving chemical anticoagulation medication could be split into 4 main groups. The most common chemical anticoagulation received was low molecular weight heparin (LMWH) (6303, 84.4 % of patients receiving chemical anticoagulation). Aspirin was given in 4.1 % (308 patients), a Factor Xa inhibitor in 10 % (744 patients) and other anticoagulants (e.g. Warfarin) in 1.5 % (114 patients). The overall VTE rate in this sub analysis of patients receiving chemical anticoagulation, was 1.1 % (83 cases out of 7469). There was no significant difference seen in incidence of VTE between types of anticoagulants, when confounding factors were considered. The duration of post-operative chemical prophylaxis used by participants for most chemical anticoagulants was 6 weeks (64.50 %). CONCLUSION: There was significant variability of chemical anticoagulants reported in the study, with five different categories of anticoagulants used (including no chemical anticoagulation), and none clearly superior/inferior. The duration of anticoagulation was consistent across types of thromboprophylaxis.

CYP2D6 Activity Is Correlated with Changes in Plasma Concentrations of Taurocholic Acid during Pregnancy and Postpartum in CYP2D6 Extensive Metabolizers.

Cytochrome P450 2D6 (CYP2D6) is involved in the metabolism of >20% of marketed drugs. CYP2D6 expression and activity exhibit high interindividual variability and is induced during pregnancy. The farnesoid X receptor (FXR) is a transcriptional regulator of CYP2D6 that is activated by bile acids. In pregnancy, elevated plasma bile acid concentrations are associated with maternal and fetal risks. However, modest changes in bile acid concentrations may occur during healthy pregnancy, thereby altering FXR signaling. A previous study demonstrated that hepatic tissue concentrations of bile acids positively correlated with the hepatic mRNA expression of CYP2D6. This study sought to characterize the plasma bile acid metabolome in healthy women (n = 47) during midpregnancy (25-28 weeks gestation) and ≥3 months postpartum and to determine if plasma bile acids correlate with CYP2D6 activity. It is hypothesized that during pregnancy, plasma bile acids would favor less hydrophobic bile acids (cholic acid vs. chenodeoxycholic acid) and that plasma concentrations of cholic acid and its conjugates would positively correlate with the urinary ratio of dextrorphan/dextromethorphan. At 25-28 weeks gestation, taurine-conjugated bile acids comprised 23% of the quantified serum bile acids compared with 7% ≥3 months postpartum. Taurocholic acid positively associated with the urinary ratio of dextrorphan/dextromethorphan, a biomarker of CYP2D6 activity. Collectively, these results confirm that the bile acid plasma metabolome differs between pregnancy and postpartum and provide evidence that taurocholic acid may impact CYP2D6 activity during pregnancy. SIGNIFICANCE STATEMENT: Bile acid homeostasis is altered in pregnancy, and plasma concentrations of taurocholic acid positively correlate with CYP2D6 activity. Differences between plasma and/or tissue concentrations of farnesoid X receptor ligands such as bile acids may contribute to the high interindividual variability in CYP2D6 expression and activity.

3-D joint space mapping at the ankle from weight-bearing CT: reproducibility, repeatability, and challenges for standardisation.

OBJECTIVES: We present a 3-D approach to joint space width (JSW) measurement across the ankle from weight-bearing CT (WBCT) to demonstrate inter-operator reproducibility, test-retest repeatability, and how differences in angulation affect ankle JSW distribution. METHODS: One side from repeat WBCT imaging of both feet and ankles was analysed from 23 individuals as part of their routine clinical care pathway. Joint space mapping was performed at four facets across the talus: talonavicular, talar dome and medial gutter (dome-medial), lateral gutter, and posterior subtalar. Inter-operator reproducibility was calculated for two users, while test-retest repeatability was calculated by comparing the two visits, both presented as Bland-Altman statistics. Statistical parametric mapping determined any significant relationships between talocrural joint space angulation and 3-D JSW distribution. RESULTS: The average ± standard deviation interval between imaging was 74.0 ± 29.6 days. Surface averaged bias ± limits of agreement were similar for reproducibility and repeatability, the latter being: talonavicular 0.01 ± 0.26 mm, dome-medial 0.00 ± 0.28 mm, lateral gutter - 0.02 ± 0.40 mm, and posterior subtalar 0.02 ± 0.34 mm. Results are presented as 3-D distribution maps, with optimum test-retest repeatability reaching a smallest detectable difference of ± 0.15 mm. CONCLUSIONS: Joint space mapping is a robust approach to 3-D quantification of JSW measurement, inter-operator reproducibility, and test-retest repeatability at the ankle, with sensitivity reaching a best value of ± 0.15 mm. Standardised imaging protocols and optimised metal artefact reduction will be needed to further understand the clinical value of these 3-D measures derived from WBCT. CLINICAL RELEVANCE STATEMENT: Weight-bearing computed tomography is an increasingly important tool in the clinical assessment of orthopaedic ankle disorders. This paper establishes the performance of measuring 3-D joint space width using this technology, which is an important surrogate marker for severity of osteoarthritis. KEY POINTS: • Joint space width values and error metrics from across the ankle measured from weight-bearing CT can be presented as 3-D maps that show topographic variation. • The best sensitivity for detecting meaningful change in 3-D joint space width at the ankle was ± 0.15 mm, a value less than the isotropic imaging voxel dimensions. • Standardised imaging protocols and optimised metal artefact reduction will be needed to understand the clinical value of 3-D measures from weight-bearing CT.

Unlocking Long-Term Stability of Upconversion Nanoparticles with Biocompatible Phosphonate-Based Polymer Coatings.

Achieving long-term (>3 months) colloidal stability of upconversion nanoparticles (UCNPs) in biologically relevant buffers has been a major challenge, which has severely limited practical implementation of UCNPs in bioimaging and nanomedicine applications. To address this challenge, nine unique copolymers formulations were prepared and evaluated as UCNP overcoatings. These polymers consisted of a poly(isobutylene-alt-maleic anhydride) (PIMA) backbone functionalized with different ratios and types of phosphonate anchoring groups and poly(ethylene glycol) (PEG) moieties. The syntheses were done as simple, one-pot nucleophilic addition reactions. These copolymers were subsequently coated onto NaYF4:Yb3+,Er3+ UCNPs, and colloidal stability was evaluated in 1 × PBS, 10 × PBS, and other buffers. UCNP colloidal stability improved (up to 4 months) when coated with copolymers containing greater proportions of anchoring groups and higher phosphonate valences. Furthermore, small molecules could be conjugated to these overcoated UCNPs by use of copper-free click chemistry, as was done to demonstrate suitability for sensor and bioprobe development.

Assessing the coronal plane deformity in Charcot Marie Tooth Cavovarus feet using automated 3D measurements.

BACKGROUND: This study assesses the coronal-plane deformities in cavovarus feet secondary to Charcot-Marie-Tooth disease (CMT) using Weightbearing-CT (WBCT) and semi-automated 3D-segmentation software. METHODS: WBCTs from 30 CMT-cavovarus feet were matched to 30 controls and analysed using semi-automatic 3D-segmentation (Bonelogic, DISIOR). The software used automated cross-section sampling with subsequent straight-line representation of weighted centre points to calculate 3D axes of bones in the hindfoot, midfoot and forefoot. Coronal relationships of these axes were analysed. Supination/pronation of the bones in relation to the ground and within each joint were measured and reported. RESULTS: The most significant deformity in CMT-cavovarus feet occurred at the talonavicular joint (TNJ) with 23 degrees more supination than normal feet (6.4 ± 14.5 versus 29.4 ± 7.0 degrees, p < 0.001). This was countered by relative pronation at the naviculo-cuneiform joints (NCJ) of 7.0 degrees (-36.0 ± 6.6 versus -43.0 ± 5.3 degrees, p < 0.001). Combined hindfoot varus and TNJ supination resulted in an additive supination effect not compensated by NCJ pronation. The cuneiforms in CMT-cavovarus feet were therefore supinated by 19.8 degrees to the ground relative to normal feet (36.0 ± 12.1 versus 16.2 ± 6.8 degrees, p < 0.001). The forefoot-arch and 1st metatarsal-ground angles demonstrated similar supination to the cuneiforms suggesting no further significant rotation occurred distally. CONCLUSION: Our results demonstrate coronal plane deformity occurs at multiple levels in CMT-cavovarus feet. Majority of the supination arises at the TNJ, and this is partially countered by pronation distally, mainly at the NCJ. An understanding of the location of coronal deformities may help when planning surgical correction. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Semi-automated 3-dimensional analysis of the normal foot and ankle using weight bearing CT - A report of normal values and bony relationships.

BACKGROUND: Foot and ankle deformities have translational and rotational components in multiple planes, at multiple levels. Semi-automatic segmentation is a relatively new technology, which when used with weight-bearing CT (WBCT), can build an accurate model of the foot and calculate the orientation and relationships of bones under physiological load. However, few papers report reference values using these techniques. We report normative values for key bony relationships based on semi-automated analysis of WBCT. METHODS: This was a single-centre, retrospective analysis of 100 feet without deformity from 55 adult patients undergoing WBCT as part of routine clinical activity (mean age 40.5 ± 17.3 years). Imaging was analysed using Bonelogic 2.1 (DISIOR, Finland). Semi-automatic segmentation was used to compute the various bony axes in 3-dimensional space. Selected coronal, axial and sagittal plane relationships were then calculated for bones of the hindfoot, midfoot and forefoot. RESULTS: Data is presented on axial and sagittal plane relationships between the metatarsals in the forefoot, and the metatarsals and cuneiforms in the midfoot. In the hindfoot, the calcaneal pitch, talar-first-metatarsal angles, talonavicular coverage angles and Saltzman angles are reported. Coronal plane axes and their relationships are reported at multiple levels from hindfoot to forefoot. Results are presented as mean values with standard deviations and 95% confidence intervals. CONCLUSIONS: We present an observational analysis of the normal values from non-deformed feet. We highlight the major relationships in the axial, sagittal and coronal planes as obtained by semi-automated analysis of WBCT. This data may serve as a reference for future research. LEVEL OF EVIDENCE: Basic science study.

Rate of COVID-19 infection and 30 day mortality between blue and green (dedicated COVID-19 safe) pathways: Results from phase 1 and 2 of the UK foot and ankle COVID-19 national (UK-FAlCoN) audit.

OBJECTIVES: The primary aim was to determine the differences in COVID-19 infection rate and 30-day mortality in patients undergoing foot and ankle surgery between different treatment pathways over the two phases of the UK-FALCON audit, spanning the first and second UK national lockdowns. SETTING: This was an ambispective (retrospective Phase 1 and prospective Phase 2) national audit of foot and ankle procedures in the UK in 2020 completed between 13th January 2020 and 30th November 2020. PARTICIPANTS: All adult patients undergoing foot and ankle surgery in an operating theatre during the study period were included from 46 participating centres in England, Scotland, Wales and Northern Ireland. Patients were categorised as either a green pathway (designated COVID-19 free) or blue pathway (no protocols to prevent COVID-19 infection). RESULTS: 10,846 patients were included, 6644 from phase 1 and 4202 from phase 2. Over the 2 phases the infection rate on a blue pathway was 1.07% (69/6470) and 0.21% on a green pathway (9/4280). In phase 1, there was no significant difference in the COVID-19 perioperative infection rate between the blue and green pathways in any element of the first phase (pre-lockdown (p = .109), lockdown (p = .923) or post-lockdown (p = .577)). However, in phase 2 there was a significant reduction in perioperative infection rate when using the green pathway in both the pre-lockdown (p < .001) and lockdown periods (Odd's Ratio 0.077, p < .001). There was no significant difference in COVID-19 related mortality between pathways. CONCLUSIONS: There was a five-fold reduction in the perioperative COVID-19 infection rate when using designated COVID-19 green pathways over the whole study period; however the success of the pathways only became significant in phase 2 of the study, where there was a 13-fold reduction in infection rate. The study shows a developing success to using green pathways in reducing the risk to patients undergoing foot and ankle surgery.

The use of intramedullary devices for fixation of metatarsal osteotomies in hallux valgus surgery - A systematic review.

BACKGROUND: Hallux valgus is a common foot condition with numerous surgical techniques described. Minimally invasive surgery is becoming more popular, with resultant development of suitable fixation devices. The aim of this systematic review was to evaluate the evidence on the use of intramedullary devices in hallux valgus first metatarsal corrective osteotomies, and describe clinical and radiological outcomes, with an overview of techniques and implants used. METHODS: We searched PubMed, Medline, Embase and EMCare databases, conforming to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Radiological outcomes including the hallux valgus angle (HVA) and intermetatarsal angle (IMA) were recorded, as well as clinical outcome scores and complications. Methodological quality of included studies was assessed using the MINORS score. RESULTS: Ten studies were included, comprising 696 feet in 745 patients. Data pooling and metanalysis was not possible due to overall low quality of evidence. Four implants were reported (Endolog, ISO Plate, V-Tek Plate, Link Fixator) and used with distal first metatarsal osteotomies, with improvement in HVA, IMA, and clinical outcome scores comparable to other fixation techniques. There were no reported cases of non-union. Complication rates were variable (all cause range of 0-21%) across all studies, with an overall low rate. CONCLUSION: Intramedullary devices are viable and safe to use for hallux valgus first metatarsal osteotomies, with comparable radiological and functional outcomes to other techniques. Current evidence base is of low methodological quality, therefore high quality studies are required to further evaluate these devices.

The UK foot and ankle COVID-19 national (FAlCoN) audit - Regional variations in COVID-19 infection and national foot and ankle surgical activity.

AIMS: This paper details the impact of COVID-19 on foot and ankle activity in the UK. It describes regional variations and COVID-19 infection rate in patients undergoing foot and ankle surgery before, during and after the first national lock-down. PATIENTS & METHODS: This was a multicentre, retrospective, UK-based, national audit on foot and ankle patients who underwent surgery between 13th January and 31st July 2020. Data was examined pre- UK national lockdown, during lockdown (23rd March to 11th May 2020) and post-lockdown. All adult patients undergoing foot and ankle surgery in an operating theatre during the study period included from 43 participating centres in England, Scotland, Wales and Northern Ireland. Regional, demographic and COVID-19 related data were captured. RESULTS: 6644 patients were included. In total 0.53% of operated patients contracted COVID-19 (n = 35). The rate of COVID-19 infection was highest during lockdown (2.11%, n = 16) and lowest after lockdown (0.16%, n = 3). Overall mean activity during lockdown was 24.44% of pre-lockdown activity with decreases in trauma, diabetic and elective foot and ankle surgery; the change in elective surgery was most marked with only 1.73% activity during lock down and 10.72% activity post lockdown as compared to pre-lockdown. There was marked regional variation in numbers of cases performed, but the proportion of decrease in cases during and after lockdown was comparable between all regions. There was also a significant difference between rates of COVID-19 and timing of peak, cumulative COVID-19 infections between regions with the highest rate noted in South East England (3.21%). The overall national peak infection rate was 1.37%, occurring during the final week of lockdown. General anaesthetic remained the most common method of anaesthesia for foot and ankle surgery, although a significant increase in regional anaesthesia was witnessed in the lock-down and post-lockdown periods. CONCLUSIONS: National surgical activity reduced significantly for all cases across the country during lockdown with only a slow subsequent increase in elective activity. The COVID-19 infection rate and peaks differed significantly across the country.

Limb salvage versus below knee amputation for severe adult lower limb deformity - A retrospective, comparative series.

BACKGROUND: This study compares outcomes of patients with severe, multiplanar, fixed, pantalar deformities undergoing limb preservation with either pantalar fusion (PTF) or talectomy and tibiocalcaneal fusion (TCF), versus below knee amputation (BKA). METHODS: Fifty-one patients undergoing either PTF, TCF and BKA for failed management of severe pantalar deformity were evaluated retrospectively. Twenty-seven patients underwent PTF, 8 TCF and 16 BKA. Median age at surgery was 55.0 years (17-72 years) and median follow-up duration was 49.9 months (24.0-253.7 months). Clinical evaluation was undertaken using the MOxFQ, EQ-5D and Special Interest Group in Amputee Medicine score (SIGAM). Patients were also asked whether they were satisfied with their surgery and whether they would have the same surgery again. RESULTS: There was no statistically significant difference in functional outcomes, satisfaction, or complications between the groups. Twenty-two patients undergoing PTF (81.5%), 6 patients undergoing TCF (75%), and 15 patients undergoing BKA (93.8%) were satisfied overall (p = 0.414). There was no difference in the proportion of patients who would opt for the same procedure again (p = 0.142): 23 in the PTF group (85.2%), 8 in the TCF group (100%), and 11 in the BKA group (68.8%). Seven patients undergoing PTF (25.9%), 2 patients undergoing TCF (25%) and 6 patients undergoing BKA (37.5%) had major complications (p = 0.692). CONCLUSION: This study concludes that PTF, TCF and BKA can all provide an acceptable outcome in treatment of severe, degenerative pantalar deformities. This data may be useful in counselling patients when considering salvage versus amputation in such cases. LEVEL OF EVIDENCE: Level 3(Original) Clinical Research Article.

Cytochrome P450 monooxygenase-mediated tailoring of triterpenoids and steroids in plants.

The cytochrome P450 monooxygenase (CYP) superfamily comprises hemethiolate enzymes that perform remarkable regio- and stereospecific oxidative chemistry. As such, CYPs are key agents for the structural and functional tailoring of triterpenoids, one of the largest classes of plant natural products with widespread applications in pharmaceuticals, food, cosmetics, and agricultural industries. In this review, we provide a full overview of 149 functionally characterised CYPs involved in the biosynthesis of triterpenoids and steroids in primary as well as in specialised metabolism. We describe the phylogenetic distribution of triterpenoid- and steroid-modifying CYPs across the plant CYPome, present a structure-based summary of their reactions, and highlight recent examples of particular interest to the field. Our review therefore provides a comprehensive up-to-date picture of CYPs involved in the biosynthesis of triterpenoids and steroids in plants as a starting point for future research.

Comparison of in-phase and opposed-phase T1W gradient echo and T2W fast spin echo dixon chemical shift imaging for the assessment of non-neoplastic, benign neoplastic and malignant marrow lesions.

OBJECTIVE: The objective of this study is to compare T1-weighted gradient echo (T1W GrE: control technique) chemical shift imaging (CSI) with T2-weighted fast spin echo (T2W FSE: experimental technique) CSI for differentiating non-neoplastic and neoplastic marrow lesions. MATERIALS AND METHODS: Patients undergoing MRI for various marrow lesions were investigated with T1W GrE and T2W FSE Dixon CSI. Signal intensity (SI) change between in-phase (IP) and opposed-phase (OP) sequences was calculated, and SI drop > 20% considered to represent non-neoplastic lesions while SI drop < 20% considered to represent neoplastic lesions. Final diagnosis was based on imaging features (n = 42) or histology (n = 43) and classified as non-neoplastic, benign neoplastic, and malignant neoplastic. Inter-observer and inter-technique agreement between 2 readers was calculated. RESULTS: The study included 85 patients (44 males and 41 females; mean age 41.1 years, range 2-83 years). Final diagnosis included 19 (22.4%) non-neoplastic lesions, 27 (31.8%) benign neoplasms, and 39 (45.9%) malignant neoplasms. On T1W GrE CSI, 19-21 lesions were classed as non-neoplastic and 64-66 as neoplastic, while on T2W FSE Dixon CSI, 22-24 lesions were classed as non-neoplastic and 61-64 as neoplastic. Lesion classification matched between the 2 techniques in 91.8-96.5% of cases. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of T1W GrE CSI for differentiating non-neoplastic and neoplastic marrow lesions were 66.7-72.2%, 88.1-89.6%, 61.9-63.2%, 90.9-92.2%, and 84.7%, and of T2W FSE Dixon CSI were 72.2-77.8%, 85.1-86.6%, 58.3-59.1%, 92.1-93.4%, and 83.5%. CONCLUSIONS: T1W GrE CSI and T2W FSE Dixon CSI produce similar results in the assessment of non-neoplastic and neoplastic marrow lesions.

An assessment of fluid-fluid levels on magnetic resonance imaging of spinal tumours.

OBJECTIVE: To assess the degree of fluid-fluid levels on MRI in spinal tumours compared with final diagnosis, and the outcome of needle biopsy in such cases. MATERIALS AND METHODS: Retrospective review of patients with a spinal tumour that contained fluid-fluid levels. Data collected included age, sex, spinal location, and final diagnosis. The outcome of needle biopsy was investigated. RESULTS: Forty-two patients were included (19 males; 24 females; mean age 27.5 years, range 5-80 years), the commonest diagnoses being aneurysmal bone cyst (n = 25; 59.5%) and metastasis (n = 5; 11.9%). All patients with a malignant diagnosis were > 50 years of age apart from 2 who had metastases from a known primary cancer, while all patients apart from 1 with aneurysmal bone cyst were < 35 years of age. Needle biopsy was undertaken in 29 cases (69%) and diagnostic in 18 (62%). Patients with FFL occupying > 2/3 of the lesion were significantly more likely to have an aneurysmal bone cyst (p = 0.008) while those with FFL occupying < 2/3 of the lesion were more likely to have a malignant tumour (p = 0.001). The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of > 2/3 FFLs occupying the lesion were 97.1%, 75%, 94.3%, 85.7%, and 92.9% respectively for differentiating a benign from a malignant spinal tumour. CONCLUSIONS: Children and younger adults with spinal lesions containing > 2/3 FFLs were very unlikely to have malignancy. However, in patients > 50 years of age or those with lesions containing < 2/3 FFLs, a malignant lesion is much more likely.

The awareness of hindfoot malalignment on non-weight-bearing ankle MRI.

OBJECTIVE: Hindfoot malalignment is a relatively common clinical finding and several studies have suggested that hindfoot valgus can be identified on non-weight-bearing ankle MRI. The aim of this study was to determine the awareness of hindfoot malalignment on ankle MRI amongst consultant musculoskeletal radiologists. MATERIALS AND METHODS: All MRI studies referred by Foot and Ankle Unit Consultants reported by one of 14 consultant musculoskeletal radiologists between March 2016 and August 2019 were retrieved from the Hospital Radiology Information System. These were reviewed independently by a radiology fellow and a consultant radiologist. Tibiocalcaneal angle (TCA) was measured, and extra-articular talocalcaneal (EA-TCI) and calcaneofibular impingement (EA-CFI) were recorded. Radiology reports were then analysed for mention of hindfoot malalignment and the presence of EA-TCI and EA-CFI. RESULTS: The study group comprised 129 patients, 46 males and 83 females with a mean age of 46.8 years (range 8-84 years). Based on review, hindfoot valgus was present in 78-80 cases (60.5-62%), EA-TCI in 30-36 cases (23.2-27.9%) and EA-CFI in 18-21 cases (14-16.3%). By comparison, MRI reports mentioned hindfoot valgus in 18 cases (2 incorrectly), EA-TCI in 8 cases (1 incorrectly) and EA-CFI in 10 cases (1 incorrectly). CONCLUSION: Hindfoot valgus, EA-TCI and EA-CFI were present relatively commonly on review of ankle MRI studies in patients referred from a specialist Foot and Ankle Unit but were commonly under-reported highlighting a relative lack of awareness of hindfoot malalignment on ankle MRI amongst musculoskeletal radiologists, which could impact negatively on patient management.

Validation of leaf enzymes in the detergent and textile industries: launching of a new platform technology.

Chemical catalysts are being replaced by biocatalysts in almost all industrial applications due to environmental concerns, thereby increasing their demand. Enzymes used in current industries are produced in microbial systems or plant seeds. We report here five newly launched leaf-enzyme products and their validation with 15 commercial microbial-enzyme products, for detergent or textile industries. Enzymes expressed in chloroplasts are functional at broad pH/temperature ranges as crude-leaf extracts, while most purified commercial enzymes showed significant loss at alkaline pH or higher temperature, required for broad range commercial applications. In contrast to commercial liquid enzymes requiring cold storage/transportation, chloroplast enzymes as a leaf powder can be stored up to 16 months at ambient temperature without loss of enzyme activity. Chloroplast-derived enzymes are stable in crude-leaf extracts without addition of protease inhibitors. Leaf lipase/mannanase crude extracts removed chocolate or mustard oil stains effectively at both low and high temperatures. Moreover, leaf lipase or mannanase crude-extracts removed stain more efficiently at 70 °C than commercial microbial enzymes (<10% activity). Endoglucanase and exoglucanase in crude leaf extracts removed dye efficiently from denim surface and depilled knitted fabric by removal of horizontal fibre strands. Due to an increased demand for enzymes in the food industry, marker-free lettuce plants expressing lipase or cellobiohydrolase were created for the first time and site-specific transgene integration/homoplasmy was confirmed by Southern blots. Thus, leaf-production platform offers a novel low-cost approach by the elimination of fermentation, purification, concentration, formulation and cold-chain storage/transportation. This is the first report of commercially launched protein products made in leaves and validated with current commercial products.

The Bologna-Oxford ankle replacement: a case series of clinical and radiological outcomes.

PURPOSE: The Bologna-Oxford (BOX®) total ankle arthroplasty (TAA) is a three-component mobile-bearing implant gaining popularity in Europe. We aimed to analyse the outcomes of this TAA. METHODS: We retrospectively analysed data on 34 consecutive BOX® TAAs performed at a single centre with a mean follow-up of 58 months. Radiographic outcomes, such as periprosthetic lucency and alignment, were measured and recorded. Prospectively captured clinical scores and range of movement (ROM) were also recorded. RESULTS: There were significant improvements in patient-reported outcome scores recorded in the Manchester-Oxford Foot Questionnaire (MOxFQ) for pain (43.8 ± 20.2, p < 0.001), standing and walking (55.6 ± 19.8, p < 0.001), social activities (45.0 ± 26.9, p < 0.02) and visual analogue score (VAS) (3.1 ± 2.5, p < 0.001). Mean improvement in ROM postoperatively was 18.7° (p < 0.001), with post-operative dorsiflexion 8.8° (10°-25°) and plantar flexion 32.6° (20°-40°). There was evidence of asymptomatic lucency on five radiographs (15%), which was present in 10% at three years. Nine patients had complications (26%): six (18%) requiring secondary surgery and one requiring revision (3%) for infection. CONCLUSIONS: We have demonstrated 97% survivorship at a mean of 58 months. There are maintained improvements in clinical and radiological outcomes and reoperation that are consistent with the literature.

The effects of weight bearing on the distal tibiofibular syndesmosis: A study comparing weight bearing-CT with conventional CT.

BACKGROUND: Syndesmotic injures are common and weight bearing imaging studies are often advocated to assess disruption. Although studies have examined the anatomical relationship between the fibula and incisura, the effect of weight-bearing on the syndesmosis has not been well reported. We characterise the changes which occur at the syndesmosis during weight-bearing. METHODS: In this retrospective review we analysed the position of the fibula at the syndesmosis in a cohort of patients who underwent both non-weight-bearing and weight-bearing CT scans. The relative position of the fibula to the incisura was analysed to determine translation and rotation in the axial plane. RESULTS: 26 patients were included. Comparison of measurements revealed statistically significant differences between groups which indicated that on weight-bearing the fibula translated laterally and posteriorly, and rotated externally with respect to the incisura. CONCLUSIONS: This is the first study to measure the differences in position of the syndesmosis during weight-bearing in a population of patients that have undergone both weight bearing and non weight bearing CT. Our study confirms that weight-bearing results in lateral and posterior translation, and external rotation of the fibula in relation to the incisura and our findings should help in future studies looking at the effect of weight bearing on syndesmotic pathology.

Gastrocnemius tightness: A population based observational study.

BACKGROUND: Gastrocnemius tightness is believed to be associated with multiple musculoskeletal pathologies such as back pain, plantar fasciitis and metatarsalgia. Although surgical treatment of gastrocnemius tightness is gaining popularity the objective definition of a gastrocnemius contracture has not been determined. The aim of our study was therefore to quantify gastrocnemius tightness in a normal population. METHODS: Adult participants with no obvious foot and ankle pathology were recruited. Gastrocnemius tightness was quantified using a weightbearing lunge test. Maximal ankle-foot dorsiflexion was measured on participants with the knee in full extension and flexed to 20° using a digital inclinometer. The ankle-foot dorsiflexion index or ADI (difference in ankle dorsiflexion with the knee extended and flexed) was calculated. The ADI values were plotted on a histogram to identify the distribution of values and were compared according to participant demographics. RESULTS: 800 limbs from 400 participants were examined. There was a wide distribution of absolute values of maximal ankle-foot dorsiflexion ranging from 8 to 52°. The ADI ranged from 0 to19° and approximated to a normal distribution. The mean ADI was 6.04±3.49° and was positively correlated with age (r=0.132, P<0.001) and negatively correlated with physical activity (r=-0.88, P=0.015). CONCLUSION(S): Our study is the first to quantify gastrocnemius tightness in a large healthy adult population with differences observed by age and physical activity. We have defined an easy and reproducible weightbearing test that can be used in both research and clinical settings. The majority of the population have some degree of gastrocnemius tightness and values of ADI greater than 13° (>2 SD of the mean), as measured by the lunge test, may be considered abnormal.