Experimental study on the biomechanical stability of complex acetabular fractures in the quadrilateral area: application of a dynamic anterior titanium-plate screw system.

BACKGROUND AND OBJECTIVE: Complex acetabular fractures involving quadrilateral areas are more challenging to treat during surgery. To date, there has been no ideal internal fixation for these acetabular fractures. The purpose of this study was to evaluate the biomechanical stability of complex acetabular fractures using a dynamic anterior titanium-plate screw system of the quadrilateral area (DAPSQ) by simulating the standing and sitting positions of pelvic specimens. MATERIALS AND METHODS: Eight formal in-preserved cadaveric pelvises aged 30-50 years were selected as the research objects. First, one hip of the normal pelvises was randomly used as the control model (group B) for measurement, and then one hip of the pelvises was randomly selected to make the fracture model in the 8 intact pelvises as the experimental model (group A) for measurement. In group A, acetabular both-column fractures in the quadrilateral area were established, and the fractures were fixed by DAPSQ. The biomechanical testing machine was used to load (simulated physiological load) from 400 N to 700 N at a 1 mm/min speed for 30 s in the vertical direction when the specimens were measured at random in simulated standing or sitting positions in groups. The horizontal displacement and longitudinal displacement of the acetabular fractures in the quadrilateral area were measured in both the standing and sitting simulations. RESULTS: As the load increased, no dislocation or internal fixation breakage occurred during the measurements. In the standing position, the horizontal displacement of the quadrilateral area fractures in group A and group B appeared to be less than 1 mm with loads ranging from 400 N to 700 N, and there was no significant difference between group A and group B (p > 0.05). The longitudinal displacement appeared to be greater than 1 mm with a load of 700 mm in group A (700 N, 2 cases), and the difference was significant between group A and group B (p < 0.05). In the sitting position, the horizontal and longitudinal displacements of the quadrilateral areas were within 0.5 mm in group A and group B, and there was no significant difference between group A and group B (p > 0.05). CONCLUSION: For complex acetabular fractures in the quadrilateral area, DAPSQ fixation may provide early sitting stability, but it is inappropriate for patients to stand too early.

Comparative study of retrograde intramedullary nailing versus locking extramedullary plating in complete articular fractures with metaphyseal comminution of the distal femur.

INTRODUCTION: Fractures of the distal femur with metaphyseal comminution and complete intra-articular involvement (AO/OTA classifications 33C2 and 33C3) present challenges for reduction and fixation. However, an optimal fixation method remains unknown. This study aimed to compare the clinical and radiographic outcomes of locking extramedullary plating (LEP) and retrograde intramedullary nailing (RIN) for complete distal femoral intra-articular fractures with metaphyseal comminution. MATERIALS AND METHODS: Between January 2016 and May 2022, 80 patients (45 men and 35 women; average age, 56.7 years) diagnosed with AO/OTA 33C2 and 33C3 were treated with either LEP or RIN and followed up for at least one year. Post-operative evaluations included radiographic assessments of bone union rate, timing, and alignment. Clinically, the knee joint range of motion (ROM), lower extremity functional scale (LEFS), and Kellgren and Lawrence (KL) grade were analyzed. The complications were also compared. RESULTS: 36 underwent LEP and 44 underwent RIN. Bone union was observed in 69.4% and 63.6% of the patients in the LEP and RIN groups, respectively (p = 0.64). The average union time was 6.9 months for the LEP group and 6.6 months for the RIN group (p = 0.51). A tendency toward varus deformity was observed in the RIN group, although the difference was not statistically significant. No significant differences were observed in knee ROM, LEFS, or KL grade. Complications included non-union (33.8%; RIN, 11; LEP, 16), varus deformity (5%; RIN, 4; LEP, 0), infection (1.3%; RIN, 0; LEP, 1), heterotrophic ossification (1.3%; RIN, 0; LEP, 1), and wound dehiscence (2.5%; RIN, 2; LEP, 0). CONCLUSIONS: The surgical fixation methods, RIN and LEP, for complete distal femoral intra-articular fractures with metaphyseal comminution showed similar clinical and radiological outcomes. However, regardless of the type of fixation device used, there was a reduced rate of bone union owing to high energy and a less favorable prognosis.

Open-loop recycling of end-of-life textiles as geopolymer fibre reinforcement.

The treatment and management of textile waste is an ever-growing issue worldwide, due to the continuously changing trends and the popularity of fast-fashion brands. There are numerous waste management methods besides simple landfilling, including reuse, open-loop or closed-loop recycling options. The described research explores the applicability of an open-loop recycling method, the processing of end-of-life textiles to produce fibres for fibre-reinforced geopolymers, to combine various waste streams for the production of an environmentally friendly binder system. By the examination of different textile waste processing methods, the most valuable fibrous material was produced with the application of a rotary shear and a vertical cutting mill, eliminating the necessity of manual cutting. As the most common base material of the textiles was found to be polyester and cotton, these were deemed useful for fibre reinforcement. The flexural strength showed a significant increase with the addition of 5 wt.% fibres, indicating the possibility of more than doubling the flexural strength of geopolymer specimens. Based on the microstructural analysis, however, even though there was good adhesion between the fibre and the geopolymer matrix, the latter showed inhomogeneities with higher fibre addition, indicating the need to further optimise the production steps, such as mixing time, vibration time, etc.

Self-Compositing: A Efficient Method of Improving the Electrical Conductivity of Graphene Nanoplatelet/Thermosetting Resin Composites.

Conductive composites based on thermosetting resins have broad applications in various fields. In this paper, a new self-compositing strategy is developed for improving the conductivity of graphene nanoplatelet/thermosetting resin composites by optimizing the transport channels. To implement this strategy, conventional graphene nanoplatelet/thermosetting resin is crushed into micron-sized composite powders, which are mixed with graphene nanoplatelets to form novel complex fillers to prepare the self-composited materials with thermosetting resins. A highly conductive compact graphene layer is formed on the surface of the crushed composite powders, while the addition of the micron-sized powder induces the orientation of graphene nanoplatelets in the resin matrix. Therefore, a highly conductive network is constructed inside the self-composited material, significantly enhancing the electrical conductivity. The composite materials based on epoxy resin, cyanate resin, and unsaturated polyester are prepared with this method, reflecting that the method is universal for preparing composites based on thermosetting resins. The highest electrical conductivity of the self-composited material based on unsaturated polyester is as high as 25.9 S m-1 . This self-compositing strategy is simple, efficient, and compatible with large-scale industrial production, thus it is a promising and general way to enhance the conductivity of thermosetting resin matrix composites.

High-frequency shock wave lithotripsy: stone comminution and evaluation of renal parenchyma injury in a porcine ex-vivo model.

BACKGROUND: The electrohydraulic high-frequency shock wave (Storz Medical, Taegerwilen, Switzerland) is a new way to create small fragments with frequencies up to 100 Hertz (Hz). This study evaluated the efficacy and safety of this method in a stone and porcine model. MATERIALS AND METHODS: BEGO stones were put in a condom in a specifically designed fixture treated with different modulations to see stone comminution. Standardized ex vivo porcine model with perfused kidneys with 26 upper and lower poles of 15 kidneys was treated with the following modulations: voltage 16-24 kV, capacitor 12 nF and frequency up to 100 Hz. 2000-20,000 shock waves were applied to each pole. The kidneys were perfused with barium sulfate solution (BaSO4) and x-ray was performed to quantify the lesions using pixel volumetry. RESULTS: There was no correlation between the number of shock waves and the powdering degree or the applied Energy and the grade of pulverization in the stone model. Regarding the perfused kidney model, the number of shock waves, applied voltage and frequency had no direct correlation with the occurrence of parenchymal lesions The detected lesions of the renal parenchyma were minimal, technical parameters had no significant impact and the lesions did not differ from the results of former experiments using 1-1.5 Hz in the same model. CONCLUSIONS: High-frequency shock wave lithotripsy can produce small stone fragments to pass in a very short time. The injury to the renal parenchyma is comparable to the results of the conventional SWL using 1-1.5 Hz.

Clinical outcomes of capitellar fractures with posterior comminution treated with Herbert screws combined with metacarpal locking plates.

BACKGROUND: The treatment of Dubberley type B capitellar fractures, which are frequently complicated, is widely debated. This study aimed to investigate the prognostic factors and clinical outcomes of Dubberley type B capitellar fractures treated with Herbert screws combined with posterior buttress plates. METHODS: Seven men and nine women (aged 30-68 years) with Dubberley type B capitellar fractures were operated on with Herbert screws combined with posterior buttress plates. The patients were classified into Dubberley types IB (seven), IIB (four), and IIIB (five). Complications and bone union were observed, and functional outcomes were evaluated by the Mayo Elbow Performance Index (MEPI). RESULTS: All patients were followed up for a mean period of 23.5 months (12-30 months). All fractures healed in 8-14 weeks (mean, 10.5 weeks). No cases of non-union, elbow instability, or avascular necrosis occurred. Degenerative arthritis occurred in 7 (44%) and heterotopic ossification in 11 (69%) patients. The median MEPI score was 92.5 (interquartile range, 85-100) points, with 11 reporting excellent, 3 good, and 2 fair outcomes. The MEPI scores of type IIIB fractures were significantly lower than those of types IB and IIB fractures, while the MEPI scores of type IB and IIB fractures did not differ significantly. CONCLUSIONS: Dubberley type IIIB capitellar fractures with multiple articular fragments have a poorer prognosis than type IB and IIB fractures. However, Herbert screw fixation combined with posterior metacarpal locking plates is feasible, providing satisfactory recovery of elbow joint function.

Is there an alternative to the Delbet-Colonna classification? Introduction and reliability assessment of a new classification system for paediatric femoral neck fractures: preliminary results.

PURPOSE: The purpose of this study was to introduce a new classification system for paediatric femoral neck fractures (PFNFs) and to evaluate its reliability. METHODS: Two hundred and eight unilateral PFNFs (mean patient age: 9.0 ± 4.8 years) were included. Based on preoperative radiographs, the new classification system distinguished PFNFs without anterior or posterior translation (Type I), PFNFs with anterior (Type II) or posterior (Type III) translation, PFNFs with a comminuted medial or posterior column (Type IV), and subtrochanteric femoral fractures (SFFs; Type V). Radiographs were evaluated twice with an interval of two weeks by 19 raters with different specialties, experiences and geographical origins. The results were compared with a selection of 50 patient age-matched unilateral PFNFs and SFFs (mean patient age: 9.1 ± 4.9 years). These were graded twice by the same graders according to the Delbet-Colonna (D-C) classification. RESULTS: Four radiologists and 15 paediatric orthopaedic surgeons from Europe and Asia graded the radiographs. Fair agreement was found between radiologists (κ = 0.296 ± 0.01) and surgeons (κ = 0.3 ± 0.005) (P = 0.17), although more experienced surgeons performed better than less experienced ones; a similar fair assessment was found for raters from Europe (κ = 0.309 ± 0.021) and Asia (κ = 0.3 ± 0.006) and for type II, III and IV fractures; the κ value in the first evaluation (0.309) was similar to that in the second evaluation (0.298). The overall κ value of the D-C classification subtypes was significantly higher (0.599 ± 0.217) than that of the new classification, 0.326 ± 0.162 (t = 3.190 P = 0.005). CONCLUSIONS: The new classification system showed fair reliability relative to the D-C classification. The reliability of the new classification system was not affected by the specialty or geographic origin of the rater or the evaluation round, only by rater experience level. The concordance was worse for PFNFs with anterior or posterior translation or with a comminuted medial or posterior columns.

Fracture line and comminution zone characteristics, and rotator cuff footprint involvement in OTA/AO 11C3-type proximal humeral fractures: complex proximal humerus fracture map.

PURPOSE: To identify fracture characteristics and zones of comminution as well as the relationship with anatomic landmarks and rotator cuff footprint involvement in OTA/AO 11C3-type proximal humerus fractures. METHODS: Computed tomography images of 201 OTA/AO 11C3 fractures were included. Fracture lines were superimposed to a 3D proximal humerus template, created from a healthy right humerus, after fracture fragment reduction on 3D reconstruction images. Rotator cuff tendon footprints were marked on the template. Lateral, anterior, posterior, medial, and superior views were captured for the interpretation of fracture line and comminution zone distribution as well as to define the relationship with anatomic landmarks and rotator cuff tendon footprints. RESULTS: A total of 106 females and 95 males (mean age = 57.5 ± 17.7 [range 18-101] years) with 103 C3.1-, 45 C3.2-, and 53 C3.3-type fractures were included. On the lateral, medial, and superior humeral surfaces, fracture lines and comminution zones were distributed differently in 3 groups. Tuberculum minus and medial calcar region were significantly less severely affected in C3.1 and C3.2 fractures than C3.3 fractures. The supraspinatus footprint was the most severely affected rotator cuff footprint area. CONCLUSIONS: Specifically defining the certain differences for repeatable fracture patterns and comminution zones in OTA/AO 11C3-type fractures and the relationship between the rotator cuff footprint and the joint capsule may contribute to the decision-making process of surgeons.

Statistical Morphology and Fragment Mapping of Complex Proximal Humeral Fractures.

Background and Objectives: Proximal humerus fractures (PHFs) are common in the elderly, but the treatment results are often poor. A clear understanding of fracture morphology and distribution of cortical bone loss is important for improved surgical decision making, operative considerations, and new implant designs. The aim of this study was to develop a 3D segmentation fracture mapping technique to create a statistical description of the spatial pattern and cortical bone loss of complex PHFs. Materials and Methods: Fifty clinical computed tomography (CT) scans of complex PHFs and their contralateral intact shoulders were collected. In-house software was developed for semi-automated segmentation and fracture line detection and was combined with manual fracture reduction to the contralateral template in a commercial software. A statistical mean model of these cases was built and used to describe probability maps of the fracture lines and cortical fragments. Results: The fracture lines predominantly passed through the surgical neck and between the tuberosities and tendon insertions. The superior aspects of the tuberosities were constant fragments where comminution was less likely. Some fracture lines passed through the bicipital sulcus, but predominantly at its edges and curving around the tuberosities proximally and distally. Conclusions: A comprehensive and systematic approach was developed for processing clinical CT images of complex fractures into fracture morphology and fragment probability maps and applied on PHFs. This information creates an important basis for better understanding of fracture morphology that could be utilized in future studies for surgical training and implant design.

Fracture lines and comminution zones in acetabular fractures based on three dimensional computed tomography.

PURPOSE: To characterize the fracture patterns of acetabular fractures and create fracture maps and comminution zones based on three-dimensional (3D) computed tomography (CT) images. METHODS: Sixty-eight computed tomography images of 67 patients (47 male [70.1%] and 20 female [29.9%], mean age: 45.2 ± 17.2 [range, 18-85 years] with the diagnosis of intra-articular acetabulum fracture were analyzed. Individual fracture lines were drawn and superimposed to a healthy acetabular template according to Judet-Letournel and simplified fracture classification systems. Fracture line, comminution zone, and heat maps were created using the computed tomography mapping technique. RESULTS: Fracture lines were distributed mainly in a horizontal and oblique orientation, which concentrated in the anteroinferior part of the joint in anterior fractures. Posterior fractures mostly had an oblique orientation, which lied between the acetabular dome and middle part of the posterior wall. In complex fractures, fracture lines were concentrated just above the cotyloid fossa, acetabular dome, and posterosuperior part of the acetabulum. The most common comminuted zones were around the central area of the articular surface and the anterior wall in anterior fractures, between the cotyloid fossa and dome in complex fractures, and the upper half posterior wall. CONCLUSION: Fracture patterns and comminution zones of acetabular fractures displayed certain characteristics. Some areas had higher comminution zones, and some areas remained intact in repeatable fracture patterns. These results may help surgeons in fixing acetabular fractures, designing new implants, and placement of acetabular component while performing THA after acetabular fractures.

Non-thermal processing has an impact on the digestibility of the muscle proteins.

Muscle proteins undergo several processes before being ready in a final consumable form. All these processes affect the digestibility of muscle proteins and subsequent release of amino acids and peptides during digestion in the human gut. The present review examines the effects of different processing techniques, such as curing, drying, ripening, comminution, aging, and marination on the digestibility of muscle proteins. The review also examines how the source of muscle proteins alters the gastrointestinal protein digestion. Processing techniques affect the structural and functional properties of muscle proteins and can affect their digestibility negatively or positively depending on the processing conditions. Some of these techniques, such as aging and mincing, can induce favorable changes in muscle proteins, such as partial unfolding or exposure of cleavage sites, and increase susceptibility to hydrolysis by digestive enzymes whereas others, such as drying and marination, can induce unfavorable changes, such as severe cross-linking, protein aggregation, oxidation induced changes or increased disulfide (S-S) bond content, thereby decreasing proteolysis. The underlying mechanisms have been discussed in detail and the conclusions drawn in the light of existing knowledge provide information with potential industrial importance.

Outcomes for a custom-made anchor-like plate combined with cerclage in the treatment of inferior pole patellar fracture.

OBJECTIVE: An inferior pole fracture of the patella requires surgical treatment to restore the knee extension mechanism of the knee joint. Different from other types of patellar fractures, inferior pole fractures are usually comminuted, and other traditional fixation methods, such as tension band wiring, may not meet the fixation needs. We propose fixing inferior pole fractures of the patella with a custom-made anchor-like plate combined with cerclage and report the surgical outcomes. MATERIAL AND METHODS: This is a retrospective clinical study. From June 2018 to August 2020, 21 patients with inferior patella fracture treated at Hong Hui Hospital Affiliated to Xi'an Jiaotong University received a custom-made anchor-like plate combined with cerclage. Complications of the surgical fixation methods and final knee function were used as the main outcome measures. RESULTS: All fractures achieved good union, and the union time ranged from 8 to 12 weeks. No patients had serious complications, such as internal fixation failure or infection. The average duration of surgery of patients was 75.05 7.26 min, and the intraoperative blood loss was 60.099.49 ml. At the last follow-up, the range of motion of the knee was 120°-140°, with an average of 131.436.92°, the Bostman score was 27-30, and the Lysholm score ranged from 82 to 95. All patients showed good knee function one year after the operation. CONCLUSION: We used a modified T-shaped plate combined with cerclage technology to fix inferior fractures pole of the patella, providing reliable fixation, allowing early functional exercise of the knee joint, and providing patients with good knee joint function after surgery.

The characteristics and influence of iatrogenic fracture comminution following antegrade interlocking nailing for simple femoral shaft fractures, a retrospective cohort study.

AIM: The incidence and characteristics of iatrogenic comminution (IC) are unknown, and the influence of IC on fracture union is unclear. This study was aimed to investigate the (1) incidence and characteristics of IC and (2) the outcomes of IC following antegrade interlocking nailing of simple femoral shaft fractures. METHODS: We retrospectively collected data on patients who experienced simple femoral shaft fractures and underwent antegrade interlocking nailing between February 2009 and December 2016. The incidence and characteristics of IC were examined. According to the presence of IC, patients were divided into two groups: an IC group and a non-IC (NIC) group. Demographic information and nonunion rates were compared between the two groups. Potential risk factors for IC (age, gender, body mass index (BMI), nail fit ratio, reduction technique, and greater trochanter nail entry) were analyzed using univariate and multivariate logistic regression. The aforementioned variables, along with IC occurrence, were also assessed as potential risk factors for nonunion at 12 and 24 months after operation using multivariate logistic regression. RESULTS: Of the 211 total patients, IC occurred in 20.9% (n = 44) of patients. Most ICs were found at the level of the isthmus, and involved the medial cortex. Compared with the NIC group, higher nonunion rates were observed in the IC group at 12 months (31.8% vs. 12.5%, p = 0.002) and 24 months (18% vs. 6.5%, p = 0.017) after surgery. Age older than 35 years old was related with the occurrence of IC in univariate analysis. Multivariate analysis found no risk factor associated with IC. Open reduction technique, IC occurrence and higher BMI were identified as the risk factors of nonunion at 12 months and 24 months after surgery in multivariate analysis. CONCLUSION: IC is a non-rare complication in antegrade interlocking nailing of simple femoral shaft fractures and was associated with higher nonunion rate. Age older than 35 years old showed a trend toward increasing risk of iatrogenic fracture comminution. In multivariate analysis, open reduction technique, IC occurrence and higher BMI significantly correlated with fracture nonunion. LEVEL OF EVIDENCE: Level IV.

Clinical and radiological outcome of the locked plate osteosynthesis in distal metadiaphyseal tibial fracture according to the severity of comminution: Varus reduction would not be preferable with lower clinical outcomes.

Background: The optimal treatment for distal tibial fractures remains a matter of debate. Nonetheless, plate osteosynthesis produces favorable results to intramedullary stabilization in aspects of alignment restoration. Aim: The aim of the study was to compare the radiologic and clinical outcomes of distal metadiaphyseal tibial fracture between a simple/wedge fracture (SWF) and a comminuted fracture (CF) using minimally invasive plate osteosynthesis (MIPO). Patients and Methods: This retrospective study analyzed patients with SWF or CF of the distal tibial metadiaphysis that was surgically treated with a locking compression plate. Postoperative radiographic assessments and the time to radiologic union were noted. Clinical assessments were evaluated using both the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the foot function index (FFI). Postoperative complications were documented. Results: Seventy-one cases were analyzed over a mean follow-up period of 20.9 months. Thirty-six patients had SWF and 35 patients presented with CF. The mean time to radiologic union, amounts of postoperative coronal angulation, and incidence of malunion showed no statistical differences. Fibular fixation was more applied in the CF group (P < 0.001). Moreover, the clinical scores revealed no differences. Nonetheless, in the valgus union group, the AOFAS ankle-hindfoot score was 90.9 compared to 84.1 in the varus union group (P = 0.042) and the FFI was 9.2% compared to 20.2% in the varus union group (P = 0.017). Conclusion: Plate osteosynthesis for SWF or CF of the distal tibial metadiaphysis led to high union rates and good clinical outcomes. There was no significant difference in the radiologic and clinical results according to the presence of fracture comminution. Nonetheless, the valgus union group showed better clinical outcomes than the varus union group. Clinically, it would be preferred to avoid intraoperative varus reduction.

Mechanochemical Synthesis of Catalytic Materials.

The mechanochemical synthesis of nanomaterials for catalytic applications is a growing research field due to its simplicity, scalability, and eco-friendliness. Besides, it provides materials with distinct features, such as nanocrystallinity, high defect concentration, and close interaction of the components in a system, which are, in most cases, unattainable by conventional routes. Consequently, this research field has recently become highly popular, particularly for the preparation of catalytic materials for various applications, ranging from chemical production over energy conversion catalysis to environmental protection. In this Review, recent studies on mechanochemistry for the synthesis of catalytic materials are discussed. Emphasis is placed on the straightforwardness of the mechanochemical route-in contrast to more conventional synthesis-in fabricating the materials, which otherwise often require harsh conditions. Distinct material properties achieved by mechanochemistry are related to their improved catalytic performance.

Rumen function and grazing behavior of early-lactation dairy cows supplemented with fodder beet.

Fodder beet (FB) is a source of readily fermentable carbohydrate that can mitigate early spring herbage deficits and correct the negative energy balance experienced during early lactation in pastoral dairy systems of New Zealand. However, the low-fiber and high-soluble carbohydrate content of both FB bulb and spring herbage are factors that promote subacute ruminal acidosis, impairing rumen function and limiting the marginal milk production response to supplement. In a crossover experiment, 8 Holstein Friesian × Jersey early-lactation dairy cows were used to test the effect of supplementing 16 kg of dry matter (DM) of a grazed perennial ryegrass herbage with 6 kg of DM/d of FB bulb (FBH) versus herbage only (HO) on changes in rumen function and grazing behavior. Following 20 d of adaptation to diets, DM disappearance (%) of FB bulb (FBH cows only) and herbage were measured in sacco, separately. Cows were fasted overnight, and the ruminal contents were bailed the following morning (~0930 h) again to determine the pool size of volatile fatty acids, ammonia, and particle size of digesta, as well as to estimate the rate of ruminal outflow and degradation of neutral detergent fiber. The FBH diet did not alter DM intake, milk yield, or milk solid (fat + protein) production compared with HO. Supplementation of herbage with FB reduced ruminal pH compared with HO between ~0800 h and 1300 h each day. During each period, 1 cow experienced severe subacute ruminal acidosis (pH <5.6 for >180 min/d) during final adaptation to the target FB allocation. The FBH diet reduced the ruminal pool of acetate and ammonia, but increased the ruminal pool of butyrate and lactate compared with HO. When fed FB, rumination and grazing time increased and grazing intensity declined compared with cows fed HO. Despite increased rumination, the comminution of large particles declined 28% between the first and second rumen bailing when cows were fed FB, and in sacco DM disappearance of perennial ryegrass declined 18% compared with cows fed HO. These results indicate that grazing dairy cows supplemented with FB (40% of daily intake) increase rumination and mastication intensity to counteract reduced ruminal degradation of ryegrass herbage due to low ruminal fluid pH.

Nailing vs. plating in comminuted proximal ulna fractures - a biomechanical analysis.

BACKGROUND: Comminuted proximal ulna fractures are severe injuries with a high degree of instability. These injuries require surgical treatment, usually angular stable plating or double plating is performed. Nailing of proximal ulna fracture is described but not performed regularly. The aim of this study was to compare a newly developed, locked proximal ulna nail with an angular stable plate in an unstable fracture of the proximal ulna. We hypothesize, that locked nailing of the proximal ulna will provide non-inferior stability compared to locked plating. METHODS: A defect fracture distal to the coronoid was simulated in 20 sawbones. After nailing or plate osteosynthesis the constructs were tested in a servo-pneumatic testing machine under physiological joint motion (0°-90°) and cyclic loading (30 N - 300 N). Intercyclic osteotomy gap motion and plastic deformation of the constructs were analyzed using micromotion video-analysis. RESULTS: The locked nail showed lower osteotomy gap motion (0.50 ± 0.15 mm) compared to the angular stable plate (1.57 ± 0.37 mm, p < 0.001). At the anterior cortex the plastic deformation of the constructs was significantly lower for the locked nail (0.09 ± 0.17 mm vs. 0.39 ± 0.27 mm, p = 0.003). No statistically significant differences were observed at the posterior cortex for both parameters. CONCLUSIONS: Nail osteosynthesis in comminuted proximal ulna fractures shows lower osteotomy gap motion and lower amount of plastic deformation compared to locking plate osteosynthesis under laboratory conditions.

A new classification of impacted proximal humerus fractures based on the morpho-volumetric evaluation of humeral head bone loss with a 3D model.

BACKGROUND: This study aimed to classify the pathomorphology of impacted proximal humeral fractures according to the control volume theory, with the intention to introduce a severity index to support surgeons in decision making. METHODS: In total, 50 proximal humeral fractures were randomly selected from 200 medical records of adult patients treated from 2009 to 2016. Four nonindependent observers used 2 different imaging modalities (computed tomography scans plus volume rendering; 3D model) to test the classification reliability. A fracture classification system was created according to the control volume theory to provide simple and understandable patterns that would help surgeons make quick assessments. The impacted fractures table was generated based on an evaluation of the calcar condition, determined by the impairment of a defined volumetric area under the cephalic cup and the humeral head malposition. In addition to the main fracture pattern, the comminution degree (low, medium, high), providing important information on fracture severity, could also be evaluated. RESULTS: From 3D imaging, the inter- and intraobserver reliability revealed a k value (95% confidence interval) of 0.55 (0.50-0.60) and 0.91 (0.79-1.00), respectively, for the pattern code, and 0.52 (0.43-0.76) and 0.91 (0.56-0.96), respectively, for the comminution degree. CONCLUSIONS: The new classification provides a useful synoptic framework for identifying complex fracture patterns. It can provide the surgeon with useful information for fracture analysis and may represent a good starting point for an automated system.

Preserving the radial head in comminuted Mason type III fractures without fixation to the radial shaft: a mid-term clinical and radiographic follow-up study.

BACKGROUND: The treatment of multifragment Mason type III fractures is challenging. Open reduction-internal fixation (ORIF), radial head arthroplasty, and in some cases, even radial head resection are the current options; however, each of these treatment methods is associated with characteristic benefits and complications. We present our experience with a radial head salvage procedure in comminuted radial head fractures irrespective of concomitant injuries, which are not accompanied by typical ORIF-related complications. METHODS: The first group comprised 29 patients with multifragment Mason type III fractures treated surgically with biological radial head spacers (group S). The fragments were reduced and fixated in an extracorporeal manner, and the reconstructed radial head was placed in its anatomic position without fixation to the shaft. The second group comprised 12 patients treated with conventional ORIF using mini-fragment plates (group P). RESULTS: Thirty patients were enrolled to undergo clinical and radiographic follow-up at an average of 76 months (range, 12-152 months). In group S, nonunion at the head-neck junction developed in 70% of the cases; however, the overall Mayo Elbow Performance Index averaged 94.8, which was superior to the average Mayo Elbow Performance Index of 83.1 in group P. Radiographic evaluation showed development of osteoarthritic changes in 75% of patients in group S and 62.5% in group P. None of the patients had wrist-joint pain. CONCLUSIONS: Preserving the native radial head in comminuted Mason type III fractures without fixation to the radial shaft is a reliable option. Excellent functional results can be expected; however, the development of osteoarthritis cannot be impeded.

Gelling properties of silver carp surimi as affected by different comminution methods: blending and shearing.

BACKGROUND: Blending and shearing, two types of comminution methods, are widely used in the manufacturing of surimi-based products. The comminution methods applied are varied to product types and manufacturers. In this study effects of different comminution methods (blending and shearing) on gelling properties of silver carp surimi were investigated. RESULTS: Regardless of comminution methods, breaking force, penetration distance and water holding capacity of surimi gel significantly increased with comminution duration up to 10 min. As compared with blending, those values under shearing of the same duration were significantly higher. Within 3 min of comminuting whiteness values of gels by shearing were significantly higher than those by blending. Electrophoresis studies showed that comminution method had no obvious effect on protein patterns. Scanning electron microscopy images revealed that more uniform and denser network was formed in the surimi gels made by shearing. Water distribution of the gels made by shearing was obviously more uniform according to magnetic resonance imaging analysis. CONCLUSION: Our results suggested that with respect to blending, shearing was a better choice to maximize the gelling ability of silver carp surimi, which resulted in the higher values of texture, whiteness and water holding capacity. It could be attributed to the denser three-dimensional network and more uniform water distribution of the surimi gel prepared by shearing. © 2019 Society of Chemical Industry.