Fixation Time Research Articles

Treatment of tibial large bone defects: A comparative study of bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate versus bone transport alone with antibiotic-impregnated calcium sulphate

PurposeTo compare the bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate versus bone transport alone with antibiotic-impregnated calcium sulphate for the treatment of tibial large bone defects. MethodsA retrospective analysis was conducted by enroling 33 surgically treated patients with tibial large bone defects after the debridement for tibial infection or osteomyelitis who were admitted in Lower Limb Surgery Ward of Traumatic orthopaedic Department, Xi'an Honghui Hospital from January 2018 to January 2021. All the patients were categorized in Group A (transport over intramedullary nail, 12 cases) and Group B (transport alone, 21 cases) based on the surgery strategy. The collected clinical materials and data included gender, age, injury mechanism, smoking habits, comorbidity diseases, initial fracture type (open or close), bone defect size, surgical duration, intraoperative bleeding loss, resorption time of calcium sulphate, bone transport time, external fixation time, external fixation index, weight bearing time, complications and Paley bone and functional criteria. ResultsThirty-three patients were enroled and successfully followed up with an average time of 15.25±4.31 months ranged from 8 to 21 months in Group A and an average time of 17.09±5.64 months ranged from 9 to 31 months in Group B. No significantly statistical differences of the demographic data were discovered between the two groups. There were no significantly statistical differences of the average bone defect size, intraoperative bleeding loss, resorption time of calcium sulphate and bone transport time between the two groups. However, the average surgical duration (P = 0.002) was significantly longer in Group A than Group B and the average external fixation time (P<0.001), external fixation index(P = 0.002) and weight bearing time (P = 0.030) were significantly shorter in Group A than Group B. No significantly statistical difference of excellent and good rate of bone outcomes and complication rate was observed, however, the excellent and good rate of functional outcomes (P = 0.041) was significantly higher in Group A than Group B. ConclusionCompared with the conventional Ilizarov technique combining with antibiotic-impregnated calcium sulphate for large tibial bone defects, bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate had favourable external fixation time, external fixation index, weight bearing time and clinical functional outcomes which effectively suppressed the infection and allowed patients earlier removal of the external fixator and weight bearing for rehabilitation.

The Surgical Timing and Complications of Rib Fixation for Rib Fractures in Geriatric Patients.

Rib fractures (RF) are a common injury that cause significant morbidity and mortality, especially in geriatric patients. RF fixation could shorten hospital stay and improve survival. The aim of this retrospective study was to evaluate the clinical impact and proper surgical timing of RF fixation in geriatric patients. We reviewed all the medical data of patients older than 16 years old with RF from the trauma registry database between January 2017 and December 2019 in Chang Gung Memorial Hospital. A total of 1078 patients with RF were enrolled, and 87 patients received RF fixation. The geriatric patients had a higher chest abbreviated injury scale than the non-geriatric group (p = 0.037). Univariate analysis showed that the RF fixation complication rates were significantly related to the injury severity scores (Odds ratio 1.10, 95% CI 1.03–1.20, p = 0.009) but not associated with age (OR 0.99, 95% CI 0.25–3.33, p = 0.988) or the surgical timing (OR 2.94, 95% CI 0.77–12.68, p = 0.122). Multivariate analysis proved that only bilateral RF was an independent risk factor of complications (OR 6.60, 95% CI 1.38–35.54, p = 0.02). RF fixation can be postponed for geriatric patients after they are stabilized and other lethal traumatic injuries are managed as a priority.

Assessing attentional bias for alcohol-related cues using eye tracking in a virtual reality environment

Several experimental paradigms were developed to measure attentional biases towards alcohol-related cues. However, most of them are based on reaction times to two-dimensional stimuli displayed on a computer screen, such that their ecological validity has been questioned. To address this, we integrated an eye tracking system into a virtual reality headset (ET-VR) and measured attentional biases in a subclinical population of alcohol users. In this exploratory study, forty social drinkers were recruited and immersed in a virtual bar including alcohol-related stimuli. Attentional focus was assessed using dwell time and number of fixations for these alcohol-related stimuli as well as for neutral stimuli unrelated to alcohol consumption. The results show that the number of fixations and, to a lesser extent, the dwell time for alcohol-related cues were positively correlated with the drinking motivation of the participants. In contrast, no significant correlation was found for neutral stimuli. In conclusion, the present study shows that alcohol-induced attentional biases can be studied using an ET-VR device in a subclinical population of alcohol users.

Non-genetic resistance facilitates survival while hindering the evolution of drug resistance due to intraspecific competition

Rising rates of resistance to antimicrobial drugs threaten the effective treatment of infections across the globe. Drug resistance has been established to emerge from non-genetic mechanisms as well as from genetic mechanisms. However, it is still unclear how non-genetic resistance affects the evolution of genetic drug resistance. We develop deterministic and stochastic population models that incorporate resource competition to quantitatively investigate the transition from non-genetic to genetic resistance during the exposure to static and cidal drugs. We find that non-genetic resistance facilitates the survival of cell populations during drug treatment while hindering the development of genetic resistance due to competition between the non-genetically and genetically resistant subpopulations. Non-genetic resistance in the presence of subpopulation competition increases the fixation times of drug resistance mutations, while increasing the probability of mutation before population extinction during cidal drug treatment. Intense intraspecific competition during drug treatment leads to extinction of susceptible and non-genetically resistant subpopulations. Alternating between drug and no drug conditions results in oscillatory population dynamics, increased resistance mutation fixation timescales, and reduced population survival. These findings advance our fundamental understanding of the evolution of resistance and may guide novel treatment strategies for patients with drug-resistant infections.

Biometric Analysis Of Emotional Responses And Cognitive Effort To Stimuli In Euhydrated Versus Hypohydrated States

Improper body water regulation contributes to physiological changes, affects mood states, and impacts regulation of behavioral responses. With the emergence of biometric analysis (facial emotions) and eye tracking technology (fixation, frequency, and duration), the ability to measure emotional responses and their focal points is now possible. PURPOSE: To examine the effects that hydration status, (euhydrated vs. hypohydrated), has on emotional responses and the intensity of these responses to two separate stimuli of a carbohydrate-electrolyte drink. METHODS: Six college aged males underwent a singular trial of active dehydration in an environmental chamber at 35 °C until 2% body water loss was achieved. Participants viewed two stimuli, pre and post dehydration in a randomized order, consisting of a video commercial (3 areas of interest (AOI)) and three still images of a carbohydrate-electrolyte drink. Biometric software and eye tracking were used to obtain mental effort (ME) scores while viewing a video commercial and still image stimuli. The order of the stimulus viewing was constant pre and post exercise but randomized amongst participants. Prior to trials, participants underwent familiarization of both stimuli. RESULTS: ME measurements, using fixations within the AOI over time (sec), increased across the video commercial (AOI 1: 10.15 ± 7.51 to 19.54 ± 16.75), (AOI 2: 6.60 ± 6.46 to 12.18 ± 12.20), and (AOI 3: 6.73 ± 4.58 to 14.68 ± 10.99) from euhydrated to hypohydrated. The three beverage still images revealed increases in ME (fixation time (sec)) from 9.04 ± 4.89 to 14.88 ± 14.76 (p = 0.002), 9.51 ± 6.90 to 13.47 ± 9.85, and 9.06 ± 4.58 to 15.31 ± 10.18 (p = 0.017), respectively. Engagement scores, measured through biometrical analysis failed to detect changes between trials across all stimuli. CONCLUSION: Increases in ME in hypohydrated states were seen across all stimuli. Data also revealed much variability among subjects. It is plausible that changes in ME within hypohydrated states impact behavioral choices. Future research should investigate the effects of greater ME and fluid consumption tendencies in regards to self-regulation of body water. Additionally, greater ME in regards to hydration stimuli could impact given task or skills performance when hypohdrated.

Distraction osteogenesis for treatment of iatrogenic shortening of the first ray

The purpose of this study is to present a surgical treatment option following iatrogenic shortened first ray pathology and report the postoperative outcomes. Retrospective analysis of two surgeon’s patients (N=5) who underwent gradual distraction osteogenesis following previously failed first ray surgery was conducted. Surgical outcomes were measured including time in the external fixator and amount of distraction achieved. Complications measured included neurovascular complications, non-union, mal-union, infections, mal-alignment, pain, wound dehiscence, stiffness and transfer metatarsalgia. The average time spent in an external fixator was 78.8 (34-108) days. Average distraction achieved was 12.2 (2-22) mm. Four of the 5 patients experienced at least one of the following postoperative complications: pin site infections, wound dehiscence, non-union and postoperative pain. This study suggests that distraction osteogenesis may be a feasible surgical treatment option for iatrogenic shortened first ray with the right patient selection, but needs further evaluation.

Acute Exercise Increases Attentional Bias Towards Food Cues

Although exercise is a common weight loss strategy, the amount of weight loss resulting from exercise training is often less than expected. This is often attributed to exercise promoting greater energy intake, resisting the exercise-induced negative energy balance required for weight loss. Prior research on how exercise can influence hormonal mediators of appetite offer conflicting results, with some demonstrating longitudinal exercise increases the satiety response to a meal and changes in hunger hormones do not predict weight loss. Research on other underlying mechanisms working to promote energy intake during exercise is scarce. PURPOSE: To determine if acute exercise influences attentional bias towards food cues. METHODS: Thirty (30) participants (BMI ≥ 25, aged 18-50 years) completed the Dot-Probe task before and 15 minutes after a bout of aerobic exercise where they expended an estimated 500 kcal and before and after a 60-minute bout of television watching (sedentary condition) on separate sessions. Sessions were separate by one week and order was counterbalanced across participants. The Dot-Probe task uses an eye-tracking device to measure the amount of time (ms) participants spent fixated on image pairs projected on a computer screen. Images included either highly appealing food (critical task stimuli) or neutral (non-food) images. Images were presented for 3,000 ms. A yellow dot appeared on either side of the screen in place of one of the previously presented images. Participants responded as quickly as possible to indicate which side the probe appeared by pressing a corresponding computer key. Mean fixation time (amount of time looking at each image) was recorded in ms. RESULTS: A condition (exercise vs sedentary) by time (pre vs post) interaction (p = 0.001) was observed where the percent of time fixated on food cues increased from 48.3% pre to 56.6% post-exercise while fixation percent changed from 50.6% pre to 49.7% post-sedentary. CONCLUSION: Acute aerobic exercise increases the environmental salience of food cues, which may increase the motivational drive to eat and resist an exercise-induced energy deficit. Attentional bias training has been successfully used to change eating behaviors and may represent a novel adjunct therapy to increase the success of an exercise for weight loss intervention.

Yang’s keyhole plate versus conventional plate for treatment of mandibular sub-condylar fractures

Objectives: The use of a keyhole plate vs two miniplates in the treatment of mandibular subcondylar fractures. Materials and methods:Twenty patients were randomized into two equal groups. Ten patients with subcondylar fractures were treated with two Yang's keyhole plates in Group I. Ten patients with subcondylar fractures were treated with two conventional miniplates in Group II. Maximum mouth opening (MMO), Protrusive excursive movement, Lateral excursive movement, and Time for reduction and fixation were all used to evaluate patients clinically vertical height of ramus, and antero-posterior condylar angulation are all measured radiographically. Results: There was a statistically non-significant difference between the study and control groups at all intervals regarding MMO, Protrusive excursive movement, Lateral excursive movement, vertical height of the ramus, antero-posterior condylar angulation, but was significant at time for reduction and fixation. Conclusion: reducing a mandibular condylar fracture using a YK-plate, the results were similar and the operating time was quicker than when utilizing a traditional mini plate fixation.

Is the timing of fixation associated with fracture-related infection among tibial plateau fracture patients with compartment syndrome? A multicenter retrospective cohort study of 729 patients

BackgroundTibial plateau fractures with an ipsilateral compartment syndrome are a clinical challenge with limited guidance regarding the best time to perform open reduction and internal fixation (ORIF) relative to fasciotomy wound closure. This study aimed to determine if the risk of fracture-related infection (FRI) differs based on the timing of tibial plateau ORIF relative to closure of ipsilateral fasciotomy wounds. MethodsA retrospective cohort study identified patients with tibial plateau fractures and an ipsilateral compartment syndrome treated with 4-compartment fasciotomy at 22 US trauma centers from 2009 to 2019. The primary outcome measure was FRI requiring operative debridement after ORIF. The ORIF timing relative to fasciotomy closure was categorized as ORIF before, at the same time as, or after fasciotomy closure. Bayesian hierarchical regression models with a neutral prior were used to determine the association between timing of ORIF and infection. The posterior probability of treatment benefit for ORIF was also determined for the three timings of ORIF relative to fasciotomy closure. ResultsOf the 729 patients who underwent ORIF of their tibial plateau fracture, 143 (19.6%) subsequently developed a FRI requiring operative treatment. Patients sustaining infections were: 21.0% of those with ORIF before (43 of 205), 15.9% at the same time as (37 of 232), and 21.6% after fasciotomy wound closure (63 of 292). ORIF at the same time as fasciotomy closure demonstrated a 91% probability of being superior to before closure (RR, 0.75; 95% CrI, 0.38 to 1.10). ORIF after fasciotomy closure had a lower likelihood (45%) of a superior outcome than before closure (RR, 1.02; 95% CrI; 0.64 to 1.39). ConclusionData from this multicenter cohort confirms previous reports of a high FRI risk in patients with a tibial plateau fracture and ipsilateral compartment syndrome. Our results suggest that ORIF at the time of fasciotomy closure has the highest probability of treatment benefit, but that infection was common with all three timings of ORIF in this difficult clinical situation.

Characteristics of emotional gaze on threatening faces in children with autism spectrum disorders.

Most evidence suggested that individuals with autism spectrum disorder (ASD) experienced gaze avoidance when looking at the eyes compared to typically developing (TD) individuals. Children with ASD magnified their fears when received threatening stimuli, resulting in a reduced duration of eye contact. Few studies have explored the gaze characteristics of children with ASD by dividing emotional faces into threatening and non-threatening pairs. In addition, although dynamic videos are more helpful in understanding the gaze characteristics of children with ASD, the experimental stimuli for some of the previous studies were still emotional pictures. We explored the viewing of dynamic threatening and non-threatening faces by children with ASD in different areas of interest (AOIs). In this study, 6–10 years old children with and without ASD viewed faces with threatening (fearful and angry) and non-threatening (sad and happy) expressions, respectively, with their eyes movements recorded. The results showed that when confronted with threatening faces, children with ASD, rather than TD, showed substantial eye avoidances, particularly non-specific avoidances in the fixation time on the mouths and significantly less time gazing at the mouths in any emotions, which was not observed for non-threatening faces. No correlations were found between the severity of symptoms and characteristics of gaze at the eyes and mouths in children with ASD. These results further enhance the understanding of the gaze characteristics of children with ASD on threatening and non-threatening faces and possibly provide additional evidence for their social interaction improvements.

893 Predictors for Infection Severity in Open Tibial Fractures

Abstract Aim Open tibial fractures can be difficult to manage - many factors could affect treatment and outcome, including being complicated by infection. We present a cohort of 244 patients and analyse which factors are significantly associated with infection outcome. Method Open tibia fractures treated at a major trauma centre between 2015–2021 were included. Infection status was categorized into no infection, superficial infection, osteomyelitis. Data collected were Age, mode of injury, polytrauma, fibula status, Gustilo-Anderson (GA) classification, wound contamination, time to first procedure. time to definitive plastics procedure, time to definitive fixation, type of definitive fixation, smoking/diabetic status, and BMI. Multicollinearity was calculated, with highly correlated factors removed. Multinomial logistic regression was performed. Chi-Squared test, with Post-Hoc Bonferroni correction was performed for complex categorical factors. Results 244 patients were included. Polytrauma and fibula status, and type of definitive fixation were excluded from the multivariate model due to strong multicollinearity. Compared to non-infected outcome, patients with superficial infection had higher BMI (p&amp;lt;0.01), higher GA grade (p&amp;lt;0.01), and osteomyelitis patients had longer time to definitive fixation (p=0.049) and longer time to definitive plastics procedure (p=0.013), higher GA grade, and wound contamination. Post-hoc analysis showed “no infection” was positively associated with GA-I (p=0.029) and GA-II (p&amp;lt;0.01), and negatively associated with GA-IIIC (p&amp;lt;0.01). Osteomyelitis was positively associated with GA-IIIc (p&amp;lt;0.01) Conclusions This study investigated associations between injury and presentation factors that may have been associated with infection. We suggest clinicians should give extra consideration to the factors highlighted during management and take preventative measures to mitigate the infection risk.

114 Bone Transport Using the Monorail External Fixator Over an Intramedullary Nail for Post-Traumatic Femoral Defects

Abstract Aim The management of limb-length discrepancy secondary to traumatic bone loss poses a unique challenge for surgeons. The Ilizarov technique is popular but is associated with long external fixator time and many complications. This retrospective study assessed outcomes of post-traumatic femoral defects managed by monorail external fixation over an intramedullary nail. Method Eight patients were included from over a four-year period with post-traumatic femoral defects, that underwent treatment with monorail fixator-assisted intramedullary nailing. Mean follow-up time was 232.83 weeks. Five were open fractures (Gustilo-Anderson type 3A:n=4, 3B:n=1), one had closed fracture. Average bone defect size was 8cm. Primary outcomes were lengthening index, consolidation time and index, external fixator index. Secondary outcomes were time to full weight bearing(FWB), time to union, complications. Patient reported outcome measures including EQ-5D-5L, SF-36, Oxford knee scores(OKS), Oxford hip scores(OHS) were recorded after recovery. Results Average consolidation time and index were 11.35months and 1.24months/cm, respectively. Mean lengthening and external fixator index were 20.2days/cm and 23.88days/cm, respectively. On average, patients achieved FWB and bone union 56.25 weeks and 68.83 weeks after bone transport initiation, respectively. Two patients had docking site non-union, treated by reamed intramedullary exchange nailing. Two patients had osteomyelitis. EQ-5D-5L and EQ-VAS scores were compared to UK population norms (p=0.104, p=0.238, respectively). Average OKS was 32.17 and OHS was 34.00. Conclusions Monorail external fixation over an intramedullary nail is an effective option for post-traumatic femoral defects, reducing external fixator time, lowering complication rate, returning patients’ quality of life to a level comparable with the normal population.

The role of spatial structures of tissues in cancer initiation dynamics

It is widely believed that biological tissues evolved to lower the risks of cancer development. One of the specific ways to minimize the chances of tumor formation comes from proper spatial organization of tissues. However, the microscopic mechanisms of underlying processes remain not fully understood. We present a theoretical investigation on the role of spatial structures in cancer initiation dynamics. In our approach, the dynamics of single mutation fixations are analyzed using analytical calculations and computer simulations by mapping them to Moran processes on graphs with different connectivity that mimic various spatial structures. It is found that while the fixation probability is not affected by modifying the spatial structures of the tissues, the fixation times can change dramatically. The slowest dynamics is observed in ‘quasi-one-dimensional’ structures, while the fastest dynamics is observed in ‘quasi-three-dimensional’ structures. Theoretical calculations also suggest that there is a critical value of the degree of graph connectivity, which mimics the spatial dimension of the tissue structure, above which the spatial structure of the tissue has no effect on the mutation fixation dynamics. An effective discrete-state stochastic model of cancer initiation is utilized to explain our theoretical results and predictions. Our theoretical analysis clarifies some important aspects on the role of the tissue spatial structures in the cancer initiation processes.

Sustainable traditional grass cloth fiber dyeing using the Taguchi L16 (4^4) orthogonal design

For many centuries, traditional grass cloth has been used as an important raw material for home textiles in China, but its market can be expanded by incorporating color. Reactive Red 2 (R2), Reactive Blue 194 (B194), and Reactive Orange 5 (O5) were used in this work to explore the dyeing behavior of sustainable traditional grass fiber using industrial dyeing methods. Initially, an L16 (4^4) orthogonal design was schematically applied to carry out the dyeing process and it was determined that the total dye fixation rate (T%) of B194 dye was the best among the three dyes. Accordingly, a statistical Taguchi technique was analyzed on a larger scale to optimize the dyeing process parameters (salt concentration, fixation time, fixation temperature, and solution pH) of B194, in which solution pH was found to be the most influential factor in achieving the highest T%. This phenomenon was also verified using analysis of variance (ANOVA), where the solution pH was found to be the biggest contributor (50%) and statistically significant (p < 0.05). Finally, confirmation tests were conducted under optimized conditions and a higher T% (53.18%) was determined compared to initial conditions (48.40%). Later, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) were used to analyze the structural characteristics and found that grass cloth was chemically stable, yet gummy materials were still observed on their surface, which was also confirmed from digital photographs. Generally, the color coordinates and fastness properties were also satisfactory.

Visual responses of patients with generalized anxiety disorder who cycling in the virtual sportscapes with different tree cover densities.

The tree density of virtual sportscape is the main factor that determines the benefits that generalized anxiety disorder (GAD) patients can obtain when they exercise with virtual environment. By using pupil size, fixation count and time as metrics, this research aimed to clarify the relationship between tree cover density and stress in the virtual environment. Ninety GAD patients were randomly grouped into the 36–60% tree density (high tree density, HTDS), 20–35% tree density (medium tree density, MTDS), or control groups (n = 30). Researchers used eye-tracking technology to analyze fixation time, fixation count and changes in pupil size to evaluate the stress changes of participants after 20 min of aerobic exercise in a virtual environment. The results showed that pupil size expanded in GAD patients after exercising in the virtual environment. Furthermore, GAD patient cycling in the MTDS group can show smaller pupil size than those in HTDS. Those results suggest that GAD patient cycling 20 min in the MTDS group can perceived lower stress. The results of eye tracking analysis showed that GAD patients spend more time and counts observing tree elements in HTDS and MTDS sportscapes. Specifically, they spent more 48% and 27% time on tree and green plants in the HTDS condition and MTDS condition, respectively, than in non-natural sportsscapes. Although 36–60% tree density of virtual natural sportscape can get more visual attention from GAD patients, 20–35% tree density of virtual natural sportscape is more capable of reducing their stress.

Effectiveness of bone transport with a locking plate versus conventional bone transport for tibial defects

To investigate the effectiveness difference between bone transport with a locking plate (BTLP) and conventional bone transport with Ilizarov/Orthofix fixators in treatment of tibial defect. The clinical data of 60 patients with tibial fractures who met the selection criteria between January 2016 and September 2020 were retrospectively analyzed, and patients were treated with BTLP (BTLP group, n=20), Ilizarov fixator (Ilizarov group, n=23), or Orthofix fixator (Orthofix group, n=17) for bone transport. There was no significant difference in gender, age, cause of injury, time from injury to admission, length of bone defect, tibial fracture typing, and comorbidities between groups ( P>0.05). The osteotomy time, the retention time of external fixator, the external fixation index, and the occurrence of postoperative complications were recorded and compared between groups. The bone healing and functional recovery were evaluated by the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria. All patients of 3 groups were followed up 13-45 months, with a mean of 20.4 months. The osteotomy time was significantly shorter in the BTLP group than in the Ilizarov group, and the retention time of external fixator and the external fixation index were significantly lower in the BTLP group than in the Ilizarov and Orthofix groups ( P<0.05). Twenty-two fractures healed in the Ilizarov group and 1 case of delayed healing; 16 fractures healed in the Orthofix group and 1 case of delayed healing; 18 fractures healed in the BTLP group and 2 cases of delayed healing. There was no significant difference between groups in fracture healing distribution ( P=0.824). After completing bone reconstruction treatment according to ASAMI criteria, the BTLP group had better bone healing than the Orthofix group and better function than the Ilizarov groups, showing significant differences ( P<0.05). Postoperative complications occurred in 4 cases (20%) in the BLTP group, 18 cases (78%) in the Ilizarov group, and 12 cases (70%) in the Orthofix group. The incidence of complication in the BTLP group was significantly lower than that in other groups ( P<0.05). BTLP is safe and effective in the treatment of tibial defects. BTLP has apparent advantages over the conventional bone transport technique in osteotomy time, external fixation index, and lower limb functional recovery.

Localizing, describing, interpreting: effects of different audio text structures on attributing meaning to digital pictures

Based on previous research on multimedia learning and text comprehension, an eye-tracking study was conducted to examine the influence of audio text coherence on visual attention and memory in a multimedia learning situation with a focus on picture comprehension. Audio text coherence was manipulated by the type of LDI structure, that is, whether localization, description, and interpretation followed in immediate succession for each pictorial detail or whether localizations and description of details were separated from their interpretation. Results show that with a LDI integrated structure compared to a LDI separated structure the referred-to picture elements were fixated longer during interpretation parts, and linkages between descriptions and interpretations were better recalled and recognized. The effects on recall and recognition of linkages were fully mediated by fixation times. This pattern of results can be explained by an interplay between audio text coherence and dual coding processes. It points out the importance of local coherence and the provision of localization information in audio explanations as well as visual attention to allow for dual coding processes that can be used to better attribute meaning to picture details. Practical implications for the design of educational videos, audio texts on websites, and audio guides are discussed.

Assessing Heterogeneity in Students' Visual Judgment: Model-Based Partitioning of Image Rankings.

Differences in the ability of students to judge images can be assessed by analyzing the individual preference order (ranking) of images. To gain insights into potential heterogeneity in judgement of visual abstraction among students, we combine Bradley–Terry preference modeling and model-based recursive partitioning. In an experiment a sample of 1,020 high-school students ranked five sets of images, three of which with respect to their level of visual abstraction. Additionally, 24 art experts and 25 novices were given the same task, while their eye movements were recorded. Results show that time spent on the task, the students’ age, and self-reported interest in visual puzzles had significant influence on rankings. Fixation time of experts and novices revealed that both groups paid more attention to ambiguous images. The presented approach makes the underlying latent scale of visual judgments quantifiable.

Application of VSD technique in adults with chronic osteomyelitis of the extremities combined with soft tissue defects.

To investigate the clinical application of vacuum sealing drainage (VSD) in chronic osteomyelitis of the extremities combined with soft tissue defects in adults. This study retrospectively included 32 adult patients with clearly diagnosed chronic osteomyelitis of the extremities combined with local soft tissue defects, and the trauma was covered by VSD after debridement, osteotomy, and vancomycin-laden bone cement filling of the occupancy, and the trauma was covered by selecting a suitable flap transfer repair according to the site and extent of the soft tissue defect after the trauma condition was suitable, and the secondary trauma was taken from the abdominal full-thickness skin free skin slice graft, according to whether the skin graft area was performed. The skin flap hematoma and infection rate, as well as the skin flap survival rate and implant fixation time were compared and analysed between the two groups. The primary outcome is the implant fixation time, and the secondary outcome is the skin fragment survival rate. In 32 patients, VSD was performed on the bone cement surface to cover the trauma, and 33.2 to 39.8kPa continuous vacuum sealing drainage was set. The average VSD time duration before soft tissue coverage was 47.87 ± 23.14 days, and the average number of VSD use was 7.18 ± 3.23. The use of VSD before soft tissue coverage did not cause complications such as negative pressure could not be maintained, vacuum sealing drainage was not smooth, skin blistering, trauma. Among the 32 patients, 12 cases of soft tissue coverage were followed by trauma free skin grafting with packing + VSD, and 20 cases were fixed with packing alone, and the duration of continuous packing and fixation of free skin pieces in the VSD group was significantly less than that in the control group (P=.006). The survival rate was significantly higher than that of the control group (P=.019). VSD in adult patients with chronic osteomyelitis of the extremities combined with soft tissue defects can effectively improve the trauma condition, provide the possibility of second-stage soft tissue coverage, and significantly shorten the preparation time for soft tissue coverage. In addition, when soft tissue coverage trauma is performed, VSD combined with skin graft packing technique can significantly improve the survival rate of skin pieces, shorten the time of skin graft fixation.

WE7.7 Bone transport using the Monorail External Fixator over an Intramedullary Nail for Post-Traumatic Femoral Defects

Abstract Aim The management of limb-length discrepancy secondary to traumatic bone loss poses an unique challenge for surgeons. The Ilizarov technique is popular, but is associated with long external fixator time and many complications. This retrospective study assessed outcomes of post-traumatic femoral defects managed by monorail external fixation over an intramedullary nail. Method Eight patients were included from over a four-year period with post-traumatic femoral defects, that underwent treatment with monorail fixator-assisted intramedullary nailing. Mean follow-up time was 232.83 weeks. Five were open fractures (Gustilo-Anderson type 3A:n=4, 3B:n=1), one had closed fracture. Average bone defect size was 8cm. Primary outcomes were lengthening index, consolidation time and index, external fixator index. Secondary outcomes were time to full weight bearing (FWB), time to union, complications. Patient reported outcome measures including EQ-5D-5L, SF-36, Oxford knee scores (OKS), Oxford hip scores (OHS) were recorded after recovery. Results Average consolidation time and index were 11.35months and 1.24months/cm, respectively. Mean lengthening and external fixator index were 20.2days/cm and 23.88days/cm, respectively. On average, patients achieved FWB and bone union 56.25 weeks and 68.83 weeks after bone transport initiation, respectively. Two patients had docking site non-union, treated by reamed intramedullary exchange nailing. Two patients had osteomyelitis. EQ-5D-5L and EQ-VAS scores were compared to UK population norms (p=0.104, p=0.238, respectively). Average OKS was 32.17 and OHS was 34.00. Conclusions Monorail external fixation over an intramedullary nail is an effective option for post-traumatic femoral defects, reducing external fixator time, lowering complication rate, returning patients’ quality of life to a level comparable with the normal population.