The fact that lateral malleolar fracture is accompanied by posterior malleolar fracture may adversely affect syndesmosis malreduction rates. We aimed to compare syndesmosis malreduction rates ...determined on postoperative radiographs between isolated lateral malleolar fractures and lateral malleolar fractures accompanied by posterior malleolar fractures.
We retrospectively examined 128 operative patients: 73 with isolated lateral malleolar fractures (group L) and 55 with lateral + posterior malleolar fractures (group LP). In group LP, no patients received posterior fragment fixation. In both groups, indirect syndesmosis fixation was performed with a single screw after open reduction and internal fixation of the lateral malleolus. Patient age, sex, fracture side, fracture type (Lauge-Hansen and Danis-Weber classifications), Kellgren-Lawrence osteoarthritis classification, syndesmotic incongruency on postoperative radiographs, syndesmotic malreduction of postoperative fibula fracture, fracture union time, complication rates, accompanying injuries, and preoperative and postoperative radiographic syndesmotic measurements (tibiofibular overlap, tibiofibular clear space, medial clear space) were recorded, and the groups were compared.
Mean ± SD age was 44.32 ± 15.66 years in group L and 48.93 ± 14.03 years in group LP (P = .087). There were no significant differences in preoperative and postoperative tibiofibular distance, tibiofibular overlap, and medial clear space values between groups (P > .05). The prevalence of grade 2 fractures according to the Kellgren-Lawrence classification was significantly higher in group LP (P = .047). Postoperative syndesmosis malreduction was detected in 12 patients in group L and in nine in group LP (P = .991).
In lateral malleolar fractures accompanied by small-fragment posterolateral or avulsion-type posterior malleolar fractures, closed syndesmotic screw fixation does not cause syndesmosis malreduction.
In this paper, numerical modeling and analysis of a HA-coated PEEK/Ti macro-composite hip stem is presented. The macro-composite hip stem consists of a titanium core in the center and a PEEK layer ...around it and a thin HA coating on the surface. The composite stem was designed and implanted in a standardized human femur bone model in SolidWorks software. The intact and postoperative femur bones were loaded like as in the single-leg stance of the walking gait and the effect of PEEK layer thickness on the internal stresses was analyzed in ANSYS software. Results were compared with an all-metallic stem model. Also, the fatigue strength of the stem and stresses occurring in the implant/coating interface were analyzed. With the composite stem, more homogeneous load distribution could be achieved, thus the stress-shielding effect was considerably reduced. Composite implants with 2 and 3 mm of PEEK layer provided sufficient fatigue strength in accordance with ASTM F2996-13 and ISO 7206-4:2010 standards. Maximum stresses at the coating/implant interface were well below the plasma-sprayed HA coatings strengths on PEEK implants. It is thought that the designed composite model may be an alternative to the standard HA-coated Ti alloy hip implants.
A homogeneous equiaxed grain structure is necessary for semisolid forming of aluminum alloys. One of the methods used to obtain such microstructure is strain induced melt activated process. The aim ...of this work is to optimize the heat treatment parameters for extruded 7075 alloy required to obtain the spheroidal grain structure suitable for thixoforging. For this purpose, 7075 was subjected to isothermal heat treatment at two different temperatures, 620 and 630
∘
C for 5, 10, 15, 20, 25, 30, 35 and 40 min. Optical microscopy analysis and mechanical tests were carried out to characterize the effects of different isothermal heat treatment parameters. Optimal heat treatment parameters were determined by the change in mechanical properties and microstructure. It was found that at 630
∘
C for 25 min resulted in 564 MPa yield stress, 616 MPa tensile stress and 5.3% elongation as the highest values in the experimental work carried out in this study.
The objective of this study was to determine volatile compounds, color parameters and sensory characteristics in raw sheep milk cheeses ripened up to 270 days using different packaging materials such ...as goat's skin bag or plastic barrel. Volatile compounds extracted by solid-phase microextraction were separated, identified and quantified using a gas chromatography (GC)-mass spectrometry detector (MS). Butanoic acid, hexanoic acid, octanoic acid, ethanol, ethyl acetate, ethyl butanoate, ethyl hexanoate, 2-butanol, 2-butanone and 2-heptanone were the predominant compounds in the volatile fraction of the cheeses. Among these, ethanol was the most abundant at the first 180 days of cheese ripening but there were 2-butanol and 2-butanone for cheese in plastic barrel (PB) and 2-heptanone for cheese in goat's skin bag (GS) at the 270 days. To best acknowledge, m-cimene, alpha-cubebene, trans-caryophylene, delto-cadinene and 16-oxasalutaridine were identified for the first time in sheep milk and its cheese. Discriminant analysis based on volatile compounds classified the cheeses according to their ripening times and also packaging materials. At the end of the ripening the differentiation between GS and PB cheeses was more evident. The results showed that GS cheese was more preferred by panelists. Cheeses ripened for more 180 days, in particular PB cheese, were much less acceptable to panelists. Therefore, in terms of optimum overall acceptability, 90 and 180 days ripening periods could be advised for the producers for PB and GS cheeses, respectively.
The posterior tibial slope (PTS) is important for performing a tibial cut that does not injure the posterior cruciate ligament (PCL). In this study, the amount of PCL fibers sacrificed under ...simulated tibial cuts with varying posterior inclinations was evaluated using magnetic resonance images (MRIs) of osteoarthritic varus knees. Knee X-rays, orthoroentgenograms, and MRIs of 113 Kellgren and Lawrence grades 3 to 4 osteoarthritic knees were included. Four different simulated tibial cuts were performed at 0, 3, 5 degrees and parallel to the tibia plateau 3 mm below of the most defective part of the cartilage in the medial plateau. Correlations between the PCL avulsion amount and the PTS and varus alignment of the lower extremity were analyzed for all four simulated tibial cut levels. The maximum amount of PCL was preserved with a 0-degree tibial cut in patients with a PTS of more than 8 degrees. With increased tibial cut angles, the posterior slope resulted in an increased amount of avulsed PCL. Although the amount of avulsed PCL was proportional with the varus alignment, it was inversely proportional with the sagittal slope. The number of injured PCLs also increased as the slope of the tibial cuts increased. Patients with mild varus alignments and high PTSs are more suitable for cruciate retaining total knee arthroplasty.
Tibiofibular injury repair of ankle fractures may result in over-compression when performed via a partially threaded screw depending on its placed level. We aimed to examine the relationship between ...the screw level relative to the tibiotalar joint and syndesmosis malreduction in postoperative radiographs of ankle fractures treated with partially threaded screws. We retrospectively analyzed 129 patients who underwent surgery due to lateral malleolar fractures between 2011 and 2019. We measured the distance between the screw and the tibiotalar joint and stratified the patients per their screw level as either trans-syndesmotic or suprasyndesmotic. According to Lauge-Hansen, 83 cases were supination-external rotation type (64.3%), and the remaining were pronation-external rotation type (35.7%) injuries. We found postoperative syndesmosis malreduction in 20 cases (15.5%). Eight (6.2%) cases had medial clear space mismatch. As the distance of the screw to the joint increased, postoperative medial clear space values increased (rho: 0.190, p = .031). The relationship between postoperative syndesmosis mismatch and the level of the syndesmotic screw was statistically significant (p = .044). In syndesmosis repair with a partially threaded screw, as the distance of the screw from the joint increases, the over-compression caused by the screw may cause an increase in postoperative syndesmotic malreduction rates.
Objective: The aim of the study was to evaluate which apparent diffusion coefficient (ADC) parameter can predict the aggressiveness of prostate cancer in patients confirmed by radical prostatectomy ...specimens. Materials and Methods: Patients who underwent radical prostatectomy for prostate cancer between October 2019 and June 2023 were retrospectively reviewed. Patients were separated into two groups based on the International Society of Urological Pathology (ISUP) classification, and the correlation between ADC metrics and ADC parameters, including ADC.sub.mean, ADC.sub.coefficient of variation (ADC.sub.cv), and ISUP classification the aggressiveness of prostate cancer was studied. Results: Fifty-seven patients were included in the study. Patients were evaluated as low-risk (group 1) (n=40), and high-risk (group) (n=17). ADC.sub.mean values for the two groups were not significantly different (p=0.218). ADC.sub.cv values that can demonstrate tumour heterogeneity index were higherin group 2 than in group 1 (p<0.001). Multivariate analysis revealed that extr acapsular extension, positive surgical margin, and ADC.sub.cv values indicated tumour proliferation, whereas seminal vesicle invasion, prostate-specific antigen levels, and body mass index were not correlated.sup.cv with ISUP grade groups. Conclusion: ADC.sub.cv is a promising new biomarker for tumour aggressiveness in prostate cancer. Keywords: Diffusion weighted imaging, apparent diffusion coefficient, ISUP grade group, prostate cancer, prostatectomy
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