Utilization of the web index in the measurement of web creep after syndactyly surgery.

The aim of this study was to explore the feasibility of using a web index to measure web creep after syndactyly surgery. A total of 19 hands in nine children (six preoperatively and 13 immediately postoperatively) underwent measurement of their web position. A preliminary study confirmed that the web index measured on the child's hand at the time of surgery was similar to that measured on photographs taken at the same time. Subsequently, an intra- and inter-observer error rate found excellent agreement among four observers measuring the web index using photographs. Of 13 postoperative webs using a winged central rectangular web flap without skin grafting, 12 were re-measured using photographs at an average of 88 months (range 78 to 96) after surgery. There was evidence of minor web creep in one web only. Our study demonstrates the efficacy of web index calculation on photographs to measure web position in children after syndactyly surgery. The study also demonstrates the effectiveness of the graftless winged central rectangular web flap technique in avoiding web creep.Level of evidence: IV.

Surgical management of clavicle fractures in Australia: an analysis of Australian Medicare Benefits Schedule database from 2001 to 2020.

BACKGROUND: There is no consensus on the optimal management of clavicle fractures, with advocates of both operative and non-operative management. The objective of this study is to assess the trends in the management of clavicle fractures in Australia over the past two decades. METHODS: The incidence of surgical fixation of clavicle fractures from 2001 to 2020 was analysed using the Australian Medicare Benefits Schedule database, reflective of operations performed on privately insured patients, thus excluding public patients and compensable cases. An offset term was utilized with data from the Australian Bureau of Statistics to account for population changes over the study period. RESULTS: A total of 17 089 procedures for the management of clavicle fractures were performed from 2001 to 2020. The incidence of operative intervention increased from 1.87 per 100 000 in 2001 to a peak of 6.63 per 100 000 in 2016. An overall increase was seen in males (310%) and females (347%) over the study period, as well as across all age groups. A greater proportion of operative interventions was performed on males (n = 14 075, 82%) than females (n = 3014, 18%, P < 0.001). The greatest increase in intervention was noted in those aged 65 or older (14% increase per year, 95% CI 11%-17%, P < 0.05). In 2020, the incidence of operative intervention decreased to a level last seen in 2013. CONCLUSIONS: The incidence of operative interventions for clavicle fractures has increased in Australia over the 20-year study period. This increase is in keeping with recent evidence suggesting several advantages when displaced mid-shaft clavicle fractures are operatively managed.

Implant Malalignment may be a Risk Factor for Poor Patient-Reported Outcomes Measures (PROMs) Following Total Knee Arthroplasty (TKA).

BACKGROUND: Implant malalignment may be a risk factor for poor patient-reported outcomes measures (PROMs) following total knee arthroplasty (TKA). METHODS: Postoperative surveys were administered to assess PROMs regarding satisfaction, pain, and function in 262 patients who underwent surgery at 4 centers in the U.S. and U.K (average age, 67.2) at a mean 5.5 years after primary TKA. Postoperative distal femoral angle (DFA), proximal tibial angle (PTA), and posterior tibial slope angle (PSA) were radiographically measured, and outliers were recorded. PROMs were compared between patients with aligned versus malaligned knees using univariate analysis. RESULTS: Patients with DFA, PTA, and PSA outliers were more likely to experience similar or decreased activity levels postoperatively than patients with no alignment outliers, as were patients with 1 or 2 outliers of any kind (P < .05). Patients with DFA, PTA, and PSA outliers were significantly more likely to be dissatisfied with their ability to perform activities of daily living (ADLs), as were patients with 1 or 2 outliers of any kind (P < .05). Patients with DFA and PSA outliers were more likely to be dissatisfied with their degree of pain relief, as were patients with 2 outliers of any kind (P < .05). Finally, patients with DFA and PSA outliers, as well as those with 1 outlier of any kind, were more likely to be dissatisfied with their overall knee function (P < .05). CONCLUSION: DFA, PTA, and PSA outliers represent a significant risk factor for decreased satisfaction with activities of daily living(ADLs), pain relief, and knee function, as well as decreased activity levels. LEVEL OF EVIDENCE: Level III.

SOX10 commonly stains scar in Mohs sections.

Sox10 immunostaining is used for the diagnosis and margin evaluation of melanocytic lesions. Sox10 was initially thought not to stain fibrohistiocytic processes. Consequently, it was believed to reliably distinguish desmoplastic melanoma from scar. However, recent data from formalin sections suggest Sox10 is less specific than previously thought. In this report, we demonstrate that Sox10-stained Mohs sections commonly show strong, fractional staining of scar. When using Sox10 with frozen section immunohistochemistry, Mohs practitioners should recognize the potential of this marker to stain scar to avoid overdiagnosis of desmoplastic melanoma.

The Impact of Surgeon Volume and Training Status on Implant Alignment in Total Knee Arthroplasty.

BACKGROUND: Implant malalignment may predispose patients to prosthetic failure following total knee arthroplasty (TKA). A more thorough understanding of the surgeon-specific factors that contribute to implant malalignment following TKA may uncover actionable strategies for improving implant survival. The purpose of this study was to determine the impact of surgeon volume and training status on malalignment. METHODS: In this retrospective multicenter study, we performed a radiographic analysis of 1,570 primary TKAs performed at 4 private academic and state-funded centers in the U.S. and U.K. Surgeons were categorized as high-volume (≥50 TKAs/year) or low-volume (<50 TKAs/year), and as a trainee (fellow/resident under the supervision of an attending surgeon) or a non-trainee (attending surgeon). On the basis of these designations, 3 groups were defined: high-volume non-trainee, low-volume non-trainee, and trainee. The postoperative medial distal femoral angle (DFA), medial proximal tibial angle (PTA), and posterior tibial slope angle (PSA) were radiographically measured. Outlier measurements were defined as follows: DFA, outside of 5° ± 3° of valgus; PTA, >±3° deviation from the neutral axis; and PSA, <0° or >7° of flexion for cruciate-retaining or <0° or >5° of flexion for posterior-stabilized TKAs. "Far outliers" were defined as measurements falling >± 2° outside of these ranges. The proportions of outliers were compared between the groups using univariate and multivariate analyses. RESULTS: When comparing the high and low-volume non-trainee groups using univariate analysis, the proportions of knees with outlier measurements for the PTA (5.3% versus 17.4%) and PSA (17.4% versus 28.3%) and the proportion of total outliers (11.8% versus 20.7%) were significantly lower in the high-volume group (all p < 0.001). The proportions of DFA (1.9% versus 6.5%), PTA (1.8% versus 5.7%), PSA (5.5% versus 12.6%), and total far outliers (3.1% versus 8.3%) were also significantly lower in the high-volume non-trainee group (all p < 0.001). Compared with the trainee group, the high-volume non-trainee group had significantly lower proportions of DFA (12.6% versus 21.6%), PTA (5.3% versus 12.0%), PSA (17.4% versus 33.3%), and total outliers (11.8% versus 22.3%) (all p < 0.001) as well as DFA (1.9% versus 3.9%; p = 0.027), PSA (5.5% versus 12.6%; p < 0.001), and total far outliers (3.1% versus 6.4%; p = 0.004). No significant differences were identified when comparing the low-volume non-trainee group and the trainee group, with the exception of PTA outliers (17.4% versus 12.0%; p = 0.041) and PTA far outliers (5.7% versus 2.6%; p = 0.033). Findings from multivariate analysis accounting for the effects of patient age, body mass index, and individual surgeon demonstrated similar results. CONCLUSIONS: Low surgical volume and trainee status were risk factors for outlier and far-outlier malalignment in primary TKA, even when accounting for differences in individual surgeon and patient characteristics. Trainee surgeons performed similarly, and certainly not inferiorly, to low-volume non-trainee surgeons. Even among high-volume non-trainees, the best-performing cohort in our study, the proportion of TKA alignment outliers was still high. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Dual Immunostaining With SOX10 and AE1/AE3 to Confirm Perineural Invasion on Mohs Sections

Perineural invasion (PNI) is associated with high risk keratinocyte carcinomas. Identification of PNI during Mohs surgery is important for staging and post-adjuvant treatment decisions but can be challenging. To confirm or exclude PNI suspected on hematoxylin and eosin sections, we performed immunohistochemical double staining on Mohs frozen sections. Neural marker SOX10 and pan-cytokeratin marker AE1/AE3 were combined in a simultaneous assay using species-specific (mouse and rabbit) antibodies and horseradish peroxidase and alkaline phosphatase detection systems. Of 23 Mohs cases with suspected PNI, 18 were confirmed to have definitive nerve involvement by tumor using double staining. Double staining frozen tissue is feasible and can be beneficial for real time confirmation of PNI during Mohs. J Drugs Dermatol. 2019;18(3):262-264.

The Role of One-Stage Exchange for Prosthetic Joint Infection.

PURPOSE OF REVIEW: In an era of increasing numbers of hip and knee replacements, strategies to manage prosthetic joint infection (PJI) that are effective at infection control with good patient-reported outcomes and cost containment for health systems are needed. Interest in single-stage exchange for PJI is rising and we assess evidence from the last 5 years related to this treatment strategy. RECENT FINDINGS: Only five series for total knee replacement and ten series for total hip replacement have been reported in the last five years. More review articles and opinion pieces have been written. Reinfection rates in these recent studies range from 0 to 65%, but a meta-analysis and systematic review of all studies showed a reinfection rate of 7.6% (95% CI 3.4-13.1) and 8.8% (95% CI 7.2-10.6) for single-stage and two-stage revisions respectively. There is emerging evidence to support single-stage revision in the setting of significant bony deficiency and atypical PJIs such as fungal infections. Prospective randomised studies are recruiting and are necessary to guide the direction of single-stage revision selection criteria. The onus of surgical excellence in mechanical removal of implants, necrotic tissue, and biofilms lies with the arthroplasty surgeon and must remain the cornerstone of treatment. Single-stage revision may be considered the first-line treatment for all PJIs unless the organism is unknown, the patient is systemically septic, or there is a poor tissue envelope.

Insights into toxic Prymnesium parvum blooms: the role of sugars and algal viruses.

Prymnesium parvum is a toxin-producing microalga that causes harmful algal blooms globally, which often result in large-scale fish kills that have severe ecological and economic implications. Although many toxins have previously been isolated from P. parvum, ambiguity still surrounds the responsible ichthyotoxins in P. parvum blooms and the biotic and abiotic factors that promote bloom toxicity. A major fish kill attributed to P. parvum occurred in Spring 2015 on the Norfolk Broads, a low-lying set of channels and lakes (Broads) found on the East of England. Here, we discuss how water samples taken during this bloom have led to diverse scientific advances ranging from toxin analysis to discovery of a new lytic virus of P. parvum, P. parvum DNA virus (PpDNAV-BW1). Taking recent literature into account, we propose key roles for sialic acids in this type of viral infection. Finally, we discuss recent practical detection and management strategies for controlling these devastating blooms.

Treatment of limb length discrepancy following total hip arthroplasty.

Limb length discrepancy is the leading cause of patient dissatisfaction following total hip arthroplasty and the most common reason for litigation in the field of orthopaedics. This article provides a systematic, stepwise approach for identifying the aetiology of limb length discrepancy following total hip arthroplasty and provides guidance on the treatment of this complication to optimize postoperative clinical and functional outcomes. This review discusses postoperative history taking, clinical examination, radiographic assessment, conservative treatment, and surgical intervention for the management of patients with established limb length discrepancy following total hip arthroplasty. A comprehensive understanding of the multifactorial nature and methods of managing postoperative limb length discrepancy is essential for optimizing patient satisfaction, clinical outcomes and long-term function following total hip arthroplasty.

Structural characterisation of the capsular polysaccharide expressed by Burkholderia thailandensis strain E555:: wbiI (pKnock-KmR) and assessment of the significance of the 2-O-acetyl group in immune protection.

Burkholderia pseudomallei and its close relative B. mallei are human pathogens that are classified as Tier 1 bio-threat agents. Both organisms have previously been shown to constitutively produce a capsular polysaccharide (CPS) that is both a virulence determinant and protective antigen. Extraction and purification of CPS for use as a potential vaccine candidate requires containment level 3 laboratories which is expensive and time-consuming. B. thailandensis strain E555 is closely related to B. pseudomallei and B. mallei, but is non-pathogenic to humans and based on immunological cross-reactivity has previously been shown to express a B. pseudomallei-like CPS. In this study, capsular polysaccharide isolated from an O-antigen deficient strain of B. thailandensis E555 was identified by 1H and 13C NMR spectroscopy as -3-)-2-O-acetyl-6-deoxy-ß-d-manno-heptopyranose-(-1, and identical to that produced by B. pseudomallei. This was further substantiated by anti-CPS monoclonal antibody binding. In connection with the production of CPS fragments for use in glycoconjugate vaccines, we set out to assess the importance or otherwise of the CPS 2-OAc groups in immune protection. To this end conjugates of the native and de-O-acetylated CPS with the Hc fragment of tetanus toxin (TetHc) were used as vaccines in a mouse model of melioidosis. The level of protection provided by deacetylated CPS was significantly lower than that from native, acetylated CPS. In addition, sera from mice vaccinated with the deacetylated CPS conjugate did not recognise native CPS. This suggests that CPS extracted from B. thailandensis can be used as antigen and that the acetyl group is essential for protection.

Contamination of the Surgical Field with Propionibacterium acnes in Primary Shoulder Arthroplasty.

BACKGROUND: Propionibacterium acnes is a common pathogen identified in postoperative shoulder infection. It has been shown to be present in culture specimens during primary shoulder arthroplasty; however, recent work has suggested that it is most likely to be a contaminant. Our aim was to identify the potential sources of contamination in shoulder arthroplasty. METHODS: Tissue swabs were obtained for microbiological analysis from consecutive patients undergoing primary shoulder arthroplasty. Routine surgical technique was maintained, and 5 specimens were taken from different sites: (1) the subdermal layer, (2) the tip of the surgeon's glove, (3) the inside scalpel blade (used for deeper incision), (4) the forceps, and (5) the outside scalpel blade (used for the skin incision). RESULTS: Forty patients (25 female patients and 15 male patients) were included. Thirteen (33%) of the 40 patients had at least 1 culture specimen positive for P. acnes. Two (8%) of the 25 female patients and 11 (73%) of the 15 male patients had ≥1 culture specimen positive for P. acnes. The most common site of growth of P. acnes was the subdermal layer (12 positive samples), followed by the forceps (7 positive samples), the tip of the surgeon's glove (7 positive samples), the outside scalpel blade (4 positive samples), and the inside scalpel blade (1 positive sample). There were 27 of 75 swabs that were positive on culture for P. acnes in male patients compared with 4 of 125 swabs in female patients. Male patients had 66 times (95% confidence interval, 6 to 680 times) higher odds of having a positive culture indicating subdermal colonization compared with female patients (p < 0.001). CONCLUSIONS: P. acnes is a common contaminant of the surgical field in primary shoulder arthroplasty. The subdermal layer may be the source of this contamination, and the prevalence of P. acnes in the surgical wound may be due to the surgeon's manipulation with gloves and instruments. Our findings are consistent with those regarding the increased rates of P. acnes bacterial load and intraoperative growth in male patients compared with female patients. CLINICAL RELEVANCE: P. acnes is likely to be spread throughout the surgical field from the subdermal layer via soft-tissue handling by the surgeon and instruments. Strategies need to be utilized to minimize this contact and to reduce the chance of colonization.

Structural Dissection of the Maltodextrin Disproportionation Cycle of the Arabidopsis Plastidial Disproportionating Enzyme 1 (DPE1).

The degradation of transitory starch in the chloroplast to provide fuel for the plant during the night requires a suite of enzymes that generate a series of short chain linear glucans. However, glucans of less than four glucose units are no longer substrates for these enzymes, whereas export from the plastid is only possible in the form of either maltose or glucose. In order to make use of maltotriose, which would otherwise accumulate, disproportionating enzyme 1 (DPE1; a 4-α-glucanotransferase) converts two molecules of maltotriose to a molecule of maltopentaose, which can now be acted on by the degradative enzymes, and one molecule of glucose that can be exported. We have determined the structure of the Arabidopsis plastidial DPE1 (AtDPE1), and, through ligand soaking experiments, we have trapped the enzyme in a variety of conformational states. AtDPE1 forms a homodimer with a deep, long, and open-ended active site canyon contained within each subunit. The canyon is divided into donor and acceptor sites with the catalytic residues at their junction; a number of loops around the active site adopt different conformations dependent on the occupancy of these sites. The "gate" is the most dynamic loop and appears to play a role in substrate capture, in particular in the binding of the acceptor molecule. Subtle changes in the configuration of the active site residues may prevent undesirable reactions or abortive hydrolysis of the covalently bound enzyme-substrate intermediate. Together, these observations allow us to delineate the complete AtDPE1 disproportionation cycle in structural terms.