Modes of failure following locking plate fixation of the distal radius: a thematic analysis of 517 fractures.

Anterior locking plate fixation of the distal radius is a common procedure with reliable results. Failure of fixation is sometimes seen. The aim of the present study was to identify the reasons for failure. In total, 517 cases met the study inclusion criteria. Of them, 23 cases had failure of fixation (4.4%). Failure analysis generated qualitative data. Subsequent thematic analysis identified the primary mode of failure and contributing factors. Primary modes were identified as failure to support all key fracture fragments (n = 20), wrong choice of implant (n = 1), failure of union (n = 1) and poor bone quality (n = 1). Contributing factors were errors in plate positioning, fracture reduction, implant selection and screw configuration, as well as fracture pattern complexity and poor bone quality. Most failed fixations had a primary mode and two or three contributing factors. Overall anterior plating is reliable with a low rate of surgical failure. Knowledge of failure modes will aid operative planning and prevent failure.Level of evidence: V.

Long-term results and explant analysis of the ReMotion total wrist arthroplasty.

The ReMotion wrist replacement has good short- to medium-term survival with an acceptable complication profile as we previously reported in a cohort of patients with rheumatoid arthritis. We now report the long-term results of the same cohort and details of explant analysis of revisions undertaken for aseptic loosening. A total of 16 wrists were reviewed. Seven prostheses remain in situ with no obvious signs of wear or radiological loosening at a mean follow-up of 15.5 years. Three wrists had been revised: one for infection and two for aseptic loosening. Five patients (six wrists) died 2-9 years after operation from unrelated causes. Explant analysis demonstrated relatively minor wear compared with the published results of the Universal-2 prosthesis. We hypothesize that this may be explained by differences in polyethylene sterilization and prosthetic design. The ReMotion wrist replacement has favourable long-term results in patients with rheumatoid arthritis with a 16-year survival rate of 78%-86%.Level of evidence: IV.

Laboratory comparison of field portable X-ray fluorescence spectrometer (FP-XRF) and inductively coupled plasma mass spectrometry (ICP-MS) for determination of airborne metals in stainless steel welding fume.

Welding fume is a common exposure in occupational settings. Gravimetric analysis for total particulate matter is common; however, the cost of laboratory analyses limits the availability of quantitative exposure assessment for welding fume metal constituents in occupational settings. We investigated whether a field portable X-ray fluorescence spectrometer (FP-XRF) could provide accurate estimates of personal exposures to metals common in welding fume (chromium, copper, manganese, nickel, vanadium, and zinc). The FP-XRF requires less training and is easier to deploy in many settings than traditional wet laboratory analyses. Filters were analyzed both by FP-XRF and inductively coupled plasma mass spectrometry (ICP-MS). We estimated the FP-XRF limit of detection for each metal and developed a correction factor accounting for the non-uniform deposition pattern on filter samples collected with an Institute of Medicine (IOM) inhalable particulate matter sampler. Strong linear correlation was observed for all metals (0.72

Germination and Simulated Gastrointestinal Digestion of Chickpea (Cicer arietinum L.) in Exhibiting In Vitro Antioxidant Activity in Gastrointestinal Epithelial Cells.

Plant-based proteins, in particular pulse proteins, have grown in popularity worldwide. Germination, or sprouting, is an effective method to release peptides and other dietary compounds. However, the combination of germination and gastrointestinal digestion in enhancing the release of dietary compounds with potential health-beneficial biological activity has yet to be entirely elucidated. The present study illustrates the impact of germination and gastrointestinal digestion on the release of dietary compounds with antioxidant activity from chickpeas (Cicer arietinum L.). Germination up to 3 days (D0 to D3) increased the peptide content by denaturing chickpea storage proteins and increased the degree of hydrolysis (DH) in the gastric phase. The antioxidant activity was measured at three different dosages (10, 50, and 100 µg/mL) and compared between D0 and D3 on human colorectal adenocarcinoma cells (HT-29). A significant increase in antioxidant activity was observed in the D3 germinated samples in all three tested dosages. Further analysis identified 10 peptides and 7 phytochemicals differentially expressed between the D0 and D3 germinated samples. Among the differentially expressed compounds, 3 phytochemicals (2',4'-dihydroxy-3,4-dimethoxychalcone, isoliquiritigenin 4-methyl ether, and 3-methoxy-4,2',5'-trihydroxychalcone) and 1 peptide (His-Ala-Lys) were identified only in the D3 samples, indicating their potential contribution towards the observed antioxidant activity.

Kynurenine Pathway Regulation at Its Critical Junctions with Fluctuation of Tryptophan.

The kynurenine pathway (KP) is the primary route for the catabolism of the essential amino acid tryptophan. The central KP metabolites are neurologically active molecules or biosynthetic precursors to critical molecules, such as NAD+. Within this pathway are three enzymes of interest, HAO, ACMSD, and AMSDH, whose substrates and/or products can spontaneously cyclize to form side products such as quinolinic acid (QA or QUIN) and picolinic acid. Due to their unstable nature for spontaneous autocyclization, it might be expected that the levels of these side products would be dependent on tryptophan intake; however, this is not the case in healthy individuals. On top of that, the regulatory mechanisms of the KP remain unknown, even after a deeper understanding of the structure and mechanism of the enzymes that handle these unstable KP metabolic intermediates. Thus, the question arises, how do these enzymes compete with the autocyclization of their substrates, especially amidst increased tryptophan levels? Here, we propose the formation of a transient enzyme complex as a regulatory mechanism for metabolite distribution between enzymatic and non-enzymatic routes during periods of increased metabolic intake. Amid high levels of tryptophan, HAO, ACMSD, and AMSDH may bind together, forming a tunnel to shuttle the metabolites through each enzyme, consequently regulating the autocyclization of their products. Though further research is required to establish the formation of transient complexation as a solution to the regulatory mysteries of the KP, our docking model studies support this new hypothesis.

Long-term outcomes of the Universal 2 total wrist replacement: revision and loosening at 10 years and beyond.

The aim of this study was to ascertain the long-term revision rates of the Universal 2 wrist prosthesis in a previously published cohort of patients with rheumatoid arthritis. The time to, and reasons for revision were determined. Radiographs were analysed to determine whether loosening had occurred in the long-term according to the Wrightington zonal classification of loosening. Seventy-eight wrists from the original cohort of 85 wrists could be identified for analysis. The longest follow-up was 16 years and 29 wrists had follow-up beyond 10 years. Seventeen wrists had been revised or were on the waiting list for revision, an overall revision rate of 22%. The 10-year survivorship was 78%. Long-term revision was commonly for periprosthetic loosening with pain and component subsidence. In those with more than 10-year follow-up, significant lucency was seen in 16 carpal components and 15 radial components. Explant analysis showed significant polyethylene wear and we postulate this is the principal reason for component loosening.Level of evidence: IV.

Arthroplasty in thumb trapeziometacarpal (CMC joint) osteoarthritis: An alternative to excision arthroplasty.

Trapeziectomy for base of thumb arthritis is well established, but base of thumb arthroplasty offers potential advantages. The review covers the development of arthroplasty for the thumb from interposition arthroplasty to total joint replacement. It discusses contemporary prosthesis designs and results, including trapezial component geometry, bearing surfaces, and dual mobility.

Splinting for the non-operative management of developmental dysplasia of the hip (DDH) in children under six months of age.

BACKGROUND: Developmental dysplasia of the hip (DDH) describes the abnormal development of a hip in childhood, ranging from complete dislocation of the hip joint to subtle immaturity of a hip that is enlocated and stable within the socket. DDH occurs in around 10 per 1000 live births, though only one per 1000 are completely dislocated. There is variation in treatment pathways for DDH, which differs between hospitals and even between clinicians within the same hospital. The variation is related to the severity of dysplasia that is believed to require treatment, and the techniques used to treat dysplasia. OBJECTIVES: To determine the effectiveness of splinting and the optimal treatment strategy for the non-operative management of DDH in babies under six months of age. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, seven other electronic databases, and two trials registers up to November 2021. We also checked reference lists, contacted study authors, and handsearched relevant meetings abstracts. SELECTION CRITERIA: Randomised controlled trials (RCTs), including quasi-RCTs, as well as non-RCTs and cohort studies conducted after 1980 were included. Participants were babies with all severities of DDH who were under six months of age. Interventions included dynamic splints, static splints or double nappies (diapers), compared to no splinting or delayed splinting. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted data and performed risk of bias and GRADE assessments. The primary outcomes were: measurement of acetabular index at years one, two and five, as determined by radiographs (angle): the need for operative intervention to achieve reduction and to address dysplasia; and complications. We also investigated other outcomes highlighted by parents as important, including the bond between parent and child and the ability of mothers to breastfeed. MAIN RESULTS: We included six RCTs or quasi-RCTs (576 babies). These were supported by 16 non-RCTs (8237 babies). Five studies had non-commercial funding, three studies stated 'no funding' and 14 studies did not state funding source. The RCTs were generally at unclear risk of bias, although we judged three RCTs to be at high risk of bias for incomplete outcome data. The non-RCTs were of moderate and critical risk of bias. We did not undertake meta-analysis due to methodological and clinical differences between studies; instead, we have summarised the results narratively. Dynamic splinting versus delayed or no splinting Four RCTs and nine non-RCTs compared immediate dynamic splinting and delayed dynamic splinting or no splinting. Of the RCTs, two considered stable hips and one considered unstable (dislocatable) hips and one jointly considered unstable and stable hips. No studies considered only dislocated hips. Two RCTs (265 babies, very low-certainty evidence) reported acetabular index at one year amongst stable or dislocatable hips. Both studies found there may be no evidence of a difference in splinting stable hips at first diagnosis compared to a strategy of active surveillance: one reported a mean difference (MD) of 0.10 (95% confidence interval (CI) -0.74 to 0.94), and the other an MD of 0.20 (95% CI -1.65 to 2.05). Two RCTs of stable hips (181 babies, very low-certainty evidence) reported there may be no evidence of a difference between groups for acetabular index at two years: one study reported an MD of -1.90 (95% CI -4.76 to 0.96), and another study reported an MD of -0.10 (95% CI -1.93 to 1.73), but did not take into account hips from the same child. No study reported data at five years. Four RCTs (434 babies, very low-certainty evidence) reported the need for surgical intervention. Three studies reported that no surgical interventions occurred. In the remaining study, two babies in the dynamic splinting group developed instability and were subsequently treated surgically. This study did not explicitly state if this treatment was to achieve concentric reduction or address residual dysplasia. Three RCTs (390 babies, very low-certainty evidence) reported no complications (avascular necrosis and femoral nerve palsy). Dynamic splinting versus static splinting One RCT and five non-RCTs compared dynamic versus static splinting. The RCT (118 hips) reported no occurrences of avascular necrosis (very low-certainty evidence) and did not report radiological outcomes or need for operative intervention. One quasi-RCT compared double nappies versus delayed or no splinting but reported no outcomes of interest. Other comparisons No RCTs compared static splinting versus delayed or no splinting or staged weaning versus immediate removal. AUTHORS' CONCLUSIONS: There is a paucity of RCT evidence for splinting for the non-operative management of DDH: we included only six RCTs with 576 babies. Moreover, there was considerable heterogeneity between the studies, precluding meta-analysis. We judged the RCT evidence for all primary outcomes as being of very low certainty, meaning we are very uncertain about the true effects. Results from individual studies provide limited evidence of intervention effects on different severities of DDH. Amongst stable dysplastic hips, there was no evidence to suggest that treatment at any stage expedited the development of the acetabulum. For dislocatable hips, a delay in treatment onset to six weeks does not appear to result in any evidence of a difference in the development of the acetabulum at one year or increased risk of surgery. However, delayed splinting may reduce the number of babies requiring treatment with a harness. No RCTs compared static splinting with delayed or no splinting, staged weaning versus immediate removal or double nappies versus delayed or no splinting. There were few operative interventions or complications amongst the RCTs and the non-randomised studies. There's no apparent signal to indicate a higher frequency of either outcome in either intervention group. Given the frequency of this disease, and the fact that many countries undertake mandatory DDH screening, there is a clear need to develop an evidence-based pathway for treatment. Particular uncertainties requiring future research are the effectiveness of splinting amongst stable dysplastic hips, the optimal timing for the onset of splinting, the optimal type of splint to use and the need for 'weaning of splints'. Only once a robust pathway for treatment is established, can we properly assess the cost-effectiveness of screening interventions for DDH.

Personal and area exposure assessment at a stainless steel fabrication facility: an evaluation of inhalable, time-resolved PM10, and bioavailable airborne metals.

This study describes a comprehensive exposure assessment in a stainless steel welding facility, measuring personal inhalable PM and metals, time-resolved PM10 area metals, and the bioavailable fraction of area inhalable metals. Eighteen participants wore personal inhalable samplers for two, nonconsecutive shifts. Area inhalable samplers and a time-resolved PM10 X-ray fluorescence spectrometer were used in different work areas each sampling day. Inhalable and bioavailable metals were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Median exposures to chromium, nickel, and manganese across all measured shifts were 66 (range: 13-300) µg/m3, 29 (5.7-132) µg/m3, and 22 (1.5-119) µg/m3, respectively. Most exposure variation was seen between workers ( 0.79

Length Matters: Short Base-Plate Angle Guides May Lead to Guide-Wire Mal-Positioning When Inserting a DHS. A Radiographic Modeling Study.

The dynamic hip screw (DHS) consists of a barrel-plate fixed to the relatively-straight proximal femoral shaft, and a screw which slides within the barrel at a fixed angle, usually 135°. The guide-wire is inserted using a guide at the set angle. Guide design varies between manufacturers, with some new guides being particularly short. We analysed the impact of guide design on the resulting trajectory of the guidewire, and its potential to cause a surgical error. Twenty AP hip radiographs were analysed. Trauma Cad (Brainlab, Munich, Germany) software was used to template a 4-hole 135° DHS onto the intact femur with the screw positioned in the center of the head. A template of a Stryker (Michigan, USA) 135° DHS guide (37 mm long) was then overlaid at the hip screw entry point, and the set trajectory marked. The divergence between the two trajectories was measured (α angle). The distance the guide would have to be moved inferiorly to attain the correct position in the head was then noted. The median divergence (α angle) caused by the guide relative to the ideal position was 6° (range 2-12). This led to the guidewire placement being a median of 9.1 mm (range 3-23) superior in the head (ß).To achieve the correct position of the wire in the head, the guide needed to be moved inferiorly a median of 8 mm (range 2-10). © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:574-577, 2020.

Pelvic pyomyositis in children: changing trends in occurrence and management.

AIMS: We present the largest series of paediatric pelvic pyomyositis from a temperate country, analyse the factors influencing long term prognosis and suggest a diagnostic protocol. MATERIALS AND METHOD: We included 41 patients diagnosed with primary paediatric pelvic pyomyositis between 1998 and 2016, in this study with a mean age of 7.5 years. Demographic, clinical, radiological and follow-up data were reviewed. Statistical analysis was performed to analyse the influence of early diagnosis and treatment on the final outcome. RESULTS: There was an increased occurrence of primary pelvic pyomyositis in the last two years. Of cases identified, 85% fulfilled Kocher's criteria for hip septic arthritis. The mean time to diagnosis was 2.8 ± 0.8 days. The most common muscle affected was obturator internus (65.85%) and multifocal involvement was common (46.34%). Early diagnosis and antibiotic treatment within seven days from the time of onset of symptoms was the only factor that influenced final outcome (p < 0.001). DISCUSSION AND CONCLUSION: Pyomyositis is no longer restricted to tropical countries. The time from onset of symptoms to start of antibiotic treatment influences the final outcome. Clinical examination and inflammatory markers have low specificity in distinguishing between pyomyositis, septic arthritis, osteomyelitis or other infections. MRI is more sensitive and can diagnose pyomyositis in its early stages. Every suspected case of septic arthritis of the hip should undergo an ultrasound. MRI scan may be performed if the ultrasound shows inconclusive evidence of an effusion. Early identification will facilitate early antibiotic treatment which will improve the final outcome. CLINICAL RELEVANCE: There is an increasing occurrence of this tropical disease in temperate countries. Early diagnosis with an MRI scan and early antibiotic use results in good outcomes.

Atopy as a Modifier of the Relationships Between Endotoxin Exposure and Symptoms Among Laboratory Animal Workers.

BACKGROUND: Exposure to endotoxin is known to trigger airway inflammation and symptoms, and atopy may modify the relationship between endotoxin exposure and symptom development. OBJECTIVE: To test the a priori hypothesis that atopic status modifies the relationship between endotoxin exposure and respiratory symptom development. METHODS: A prospective study of laboratory workers at The Jackson Laboratories was conducted. Allergy skin testing was performed and population demographic and clinical information was obtained at baseline. Personal exposure assessments for airborne endotoxin and surveys of self-reported symptoms were performed every 6 months. Cox proportional hazards models were used to examine the relationship between endotoxin exposure and development of mouse-associated symptoms and multivariate regression was used to test for interaction. RESULTS: Overall, 16 (9%) of 174 worker-participants developed mouse-associated rhinoconjunctivitis symptoms by 24 months and 8 (5%) developed mouse-associated lower respiratory symptoms by 24 months. Among workers with endotoxin exposure above the median (≥2.4 EU m-3), 5 (6% of 80) atopics reported mouse-associated rhinoconjunctivitis symptoms at 24 months as compared to 3 (3% of 94) non-atopics. Among workers below the median endotoxin exposure (<2.4 EU m-3), 1 (1% of 80) atopic reported mouse-associated rhinoconjunctivitis symptoms at 24 months as compared to 7 (7% of 94) non-atopics. For the combination of symptoms, the adjusted hazard ratio was 6.8 (95% confidence interval: 0.7-67.2) for atopics and 0.07 (95% confidence interval: 0.01-0.5) for non-atopics. CONCLUSION: In this occupational cohort, atopic workers may be more susceptible to, and non-atopic workers protected from, endotoxin-associated upper and lower respiratory symptoms.

Simple radiographic assessment of bone quality is associated with loss of surgical fixation in patients with proximal humeral fractures.

AIM: This study aimed to determine if the ratio of cortical thickness to shaft diameter of the humerus, as measured on a simple anterior-posterior shoulder radiograph, is associated with surgical fixation failure. PATIENTS AND METHODS: 64 consecutive fractures in 63 patients (mean age 66.1 years, range 35-90) operated with surgical fixation between March 2011 and July 2014 using PERI-LOC locking plate and screws (Smith and Nephew, UK) were identified. Predictors of bone quality were measured from preoperative radiographs, including ratio of the medial cortex to shaft diameter (medial cortical ratio, MCR). Loss of fixation (displacement, screw cut out, or change in neck-shaft angle >4 degrees) was determined on follow-up radiographs. RESULTS: Loss of fixation occurred in 14 patients (21.9%) during the follow up. Patients were older in the failure group 72.8 vs. 64.2 years (p=0.007). The MCR was significantly lower in patients with failed fixation 0.170 vs 0.202, p=0.019. Loss of fixation is three times more likely in patients with a MCR <0.16 (41% vs. 14%, p=0.015). Increased fracture parts led to increased failure rate (p=0.0005). CONCLUSION: Medial cortex ratio is significantly associated with loss of surgical fixation and may prove to be a useful adjunct for clinical decision making in patients with proximal humeral fractures.

The litigation cost of negligent scaphoid fracture management.

The aims of the study were to quantify the litigation cost of scaphoid mismanagement, identify the main reasons why patients sought compensation and hence provide suggestions for reducing litigation. Data were obtained from the National Health Service Litigation Authority. All orthopaedic-related litigation between 1995 and 2010 in the UK was reviewed. Litigation specifically against mismanagement of scaphoid fractures were identified and grouped according to the plaintiff's complaint. Exclusions were all unsettled claims. There were 85 closed cases of scaphoid fracture mismanagement over 15 years. Reasons for litigation were as follows: seven failures in interpreting radiographs, 57 missed fractures, four fractures not immobilized, nine discharged too early, five delayed operations and three inappropriate surgeries. The mean cost was &OV0556;41 680 per case (range &OV0556;0-&OV0556;206 789), and a cumulative cost of &OV0556;3 542 855. The majority of litigation may relate to a lack of follow-up and may demonstrate a failure of protocol-driven reassessment. Secondary surveys following major trauma are also highly relevant.

Differential distribution of cobalt, chromium, and nickel between whole blood, plasma and urine in patients after metal-on-metal (MoM) hip arthroplasty.

Evidence shows that raised cobalt (Co), chromium (Cr), and nickel (Ni) whole blood concentrations correlate with poor device outcome in patients following metal-on-metal (MoM) hip arthroplasty. To understand the local and systemic pathological effects of these raised metal concentrations it is important to define their distribution between whole blood, plasma, and urine. The metals were measured by Inductively Coupled Plasma Mass Spectrometry (ICPMS). Two hundred and five plasma, 199 whole blood, and 24 sets of urine samples were analyzed from 202 patients with Co-Cr alloy MoM hip prostheses implanted between 8 months to 12 years (mean 6.0 years) prior to analysis. Plasma Co (median 39.1 nmol/L) showed significantly positive 1:1 correlation with whole blood Co (median 45.9 nmol/L; R(2) = 0.98, p < 0.001, slope = 1.0). Plasma Cr (median 53.8 nmol/L) and whole blood Cr (median 40.3 nmol/L) were also correlated; however, concentrations were significantly higher in plasma indicating relatively little blood cell uptake (R(2) = 0.96, p < 0.001, slope = 1.6). Urinary Co was up to threefold higher than Cr (median 334.0 vs. 97.3 nmol/L respectively). Nickel concentrations in whole blood, plasma, and urine were low relative to Co and Cr. The analysis shows fundamental differences in the physiological handling of these metals: Co is distributed approximately equally between blood cells and plasma, whereas Cr is mainly in plasma, despite which, Cr had far less renal excretion than Co.

Teaching toolkit for medical students.

BACKGROUND: From teaching juniors and peers to educating patients, it is imperative for all doctors to have basic core teaching skills. The Junior Association for the Study of Medical Education (JASME) felt that a short course in the fundamentals of teaching would be well received by students. CONTEXT: This article shares the lessons from a one-day teaching course aimed at senior medical students. Qualitative feedback helped decide which aspects of the course were most valued. INTERVENTION: The course was piloted in London. It combined interactive plenary sessions on teaching theory with practical teaching sessions. Each student taught a small group of others a basic clinical skill, and the student teacher then received extensive feedback from their peers and an experienced clinician with a special interest in medical education. There was an opportunity to re-teach part of the skill after having taken the feedback on board. IMPLICATIONS: Students completed questionnaires at the start and end of the day to ascertain their expectations of the course and what they found most useful. Expectations can be grouped into three main areas: students wanted to improve their teaching skills; gain teaching experience; and receive feedback on their teaching. The most valuable part of the course was being able to practise teaching and receive feedback. Keywords used to describe the feedback included 'individual', 'valuable', 'constructive', 'instant' and 'in depth'. By continuing to run similar workshops we hope that we can further encourage the teachers of tomorrow.