Plate Fracture Research Articles

The biomechanical properties of the hook plate and pull-out suture in mallet finger fractures: a cadaveric study.

A total of 32 cadaveric fingers with bony mallet injuries were fixed using either the hook plate or the pull-out suture technique. The purpose of this study was to assess the immediate postoperative biomechanical responses of the fixation techniques under different load conditions. The fingers were cyclically loaded with a force of 7 N for 3500 cycles and until construct failure. The maximum displacements of the hook plate and pull-out sutures were 0.7 mm and 0.6 mm, respectively (p = 0.556). The stiffnesses of the hook plate and pull-out suture were 1.3 N/mm and 1.1 N/mm, respectively (p = 0.515). The ultimate loads-to-failure for the hook plate and pull-out suture were 64.4 N (interquartile range [IQR] 37.7-77.7) and 44.5 N (IQR 29.7-63.5), respectively (p = 0.094). Both fixation techniques were able to withstand immediate postoperative mobilization without any difference in fracture displacement, construct stiffness or maximum load to failure.

What Are the Long-term Outcomes of Locking Plates for Nonosteoporotic Three-part and Four-part Proximal Humeral Fractures With a Minimum 10-year Follow-up Period?

Proximal humeral fractures (PHFs) often occur in elderly individuals who experience low-energy falls. Open reduction and internal fixation (ORIF) of the proximal humerus is typically performed in young, active patients because of their good bone quality and high functional demands. Although good short-term results have been reported after ORIF in young patients, few studies have specifically evaluated long-term outcomes. (1) What are the long-term clinical outcomes scores and (2) radiologic outcomes of nonosteoporotic three-part and four-part PHFs treated with locking plates? (3) What complications occurred after treatment, and what factors are associated with poor postoperative functional outcomes scores and avascular necrosis (AVN) of the humeral head after ORIF? Between June 2005 and December 2012, we surgically treated 774 patients for displaced two-, three-, and four-part PHFs. Approximately 75% (581 of 774) underwent ORIF, 10% (77 of 774) underwent hemiarthroplasty, 7% (54 of 774) underwent intramedullary nailing, 5% (39 of 774) underwent reverse shoulder arthroplasty, and the remaining 3% (23 of 774) underwent other surgical treatments. We considered those who had ORIF as potentially eligible. Based on that criterion, 75% (581) were eligible. However, only patients with nonosteoporotic three- and four-part PHFs (cortical thickness of the proximal humeral diaphysis greater than 6 mm on a preoperative AP radiograph of the affected shoulder) and a minimum of 10 years of follow-up were included. Sixty-four percent (498 of 774) of the patients were excluded because of simple or osteoporotic fractures, 1% (7 of 774) were excluded because of ipsilateral limb multiple fractures, 0.3% (2 of 774) were excluded because of pathologic PHFs, and another 2% (13 of 774) were lost before the minimum study follow-up of 10 years, leaving 8% (61 of 774) for analysis here. The mean age at surgery was 45 ± 12 years, with a mean follow-up of 13 years. Fifty-seven percent (35 of 61) of the patients were men. Patient-reported outcomes were evaluated using the University of California Loas Angeles (UCLA) score (range 0 to 35; higher scores represent better shoulder function) and Constant score (range 0 to 100; higher scores represent better shoulder function) at least 10 years postoperatively. Postoperative radiographs were reviewed to assess the cortical bone thickness of the proximal humerus, neck-shaft angle, head-to-tuberosity distance, and radiologically confirmable complications. Logistic regression analysis was performed to evaluate factors associated with poor postoperative functional scores (UCLA score ≤ 27 or Constant score ≤ 70) and AVN of the humeral head; the association between AVN and postoperative functional outcomes was also assessed. At the most-recent follow-up, these patients had a mean UCLA score of 31 ± 3 and a Constant score of 88 ± 10. The mean neck-shaft angle was 133° ± 10°, and 23% (14 of 61) of patients experienced AVN of the humeral head during follow-up. Twenty-nine complications in 30% (18 of 61) of patients were reported. After controlling for potentially confounding variables such as age and gender, we found that the presence of greater tuberosity malposition (odds ratio 18 [95% confidence interval 2 to 167]; p = 0.01) and immediate postoperative neck-shaft angle less than 130° (OR 19 [95% CI 3 to 127]; p = 0.002) were associated with poor postoperative functional scores. Four-part PHFs (OR 13 [95% CI 2 to 82]; p = 0.008) and metaphyseal extension less than 8 mm (OR 7 [95% CI 1 to 35]; p = 0.03) were associated with AVN of the humeral head. For patients who met the criteria for anatomic reduction (achievement of all of the following three criteria: neck-shaft angle ≥ 130°, head-shaft displacement < 5 mm, and head-to-tuberosity distance greater than or equal to 3 mm and less than or equal to 20 mm), there were no differences in postoperative functional scores between patients with AVN and those without. ORIF of nonosteoporotic proximal humeral fractures with locking plates led to favorable functional and radiologic outcomes at a minimum of 10 years of follow-up. When encountering complex PHFs in patients with good bone quality, every effort must be made to achieve an anatomic reduction of the fracture as far as possible, which may not reduce the risk of AVN (this occurred in nearly one-fourth of patients). However, good outcomes can usually be expected, even in patients with AVN. Because this was a retrospective study with a high risk of bias owing to sparse data, the factors associated with poor postoperative functional outcomes must be further investigated in large prospective studies. Level III, therapeutic study.

Comparison between Novel Anatomical Locking Guide Plate and Conventional Locking Plate for Acetabular Fractures: A Finite Element Analysis.

The treatment of complex acetabular fractures remains a complicated clinical challenge. Our self-designed novel anatomical locking guide plate (NALGP) has previously shown promising potential in T-shaped acetabular fractures (TAF), but a direct comparison with conventional fixations is yet to be made. The TAF model was established based on a volunteer's computer tomography data and then fixed with double column locking plates (DLP), a posterior column locking plate with anterior column screws (LPACS), and our NALGP. Forces of 200 N, 400 N, and 600 N were then loaded on the model vertically downward, respectively. The stress distribution and peaks and maximum displacements at three sites were assessed. We found that the stress area of all three plates was mainly concentrated around the fracture line, while only the matching screws of the NALGP showed no obvious stress concentration points. In addition, the NALGP and DLP showed significantly less fracture fragment displacement than the LPACS at the three main fracture sites. The NALGP was found to have less displacement than DLP at the posterior column and ischiopubic branch sites, especially under the higher loading forces of 400 N and 600 N. The fixation stability of the NALGP for TAF was similar to that of DLP but better than that of LPACS. Moreover, the NALGP and its matching screws have a more reasonable stress distribution under different loads of force and the same strength as the LPACS.

The Moderating Effect of Age on Patient-Reported Benefits From Operative Management of Intra-Articular Distal Radius Fractures: A Meta-Regression Analysis

The optimal treatment of intra-articular distal radius fractures in older adults (>65 years) remains uncertain despite numerous randomized trials. The purpose of this study was to examine the moderating effect of age on patient-reported benefits of volar locked plating versus cast immobilization for intra-articular distal radius fractures. A meta-analysis of randomized controlled trials was conducted to compare volar locked plating and cast immobilization of intra-articular distal radius fractures. Meta-regression analyses were used to examine the moderating effect of age on improvements in patient-reported outcome measures from operative treatment of distal radius factures. Modeling results were then used to estimate improvements in Disability of the Arm, Shoulder, and Hand (DASH) scores from surgery that are associated with ages ranging from 65 to 90 years. Twelve randomized controlled trials including 1,806 patients were included. Age was a significant moderator of patient-reported benefits after operative treatment, with decreasing DASH score benefits from surgery associated with older ages. Model predictions show that a majority of patients aged <70 years will experience a clinically meaningful improvement in DASH scores from surgery. Patients aged 70-80 years have decreasing DASH benefits with age, but many may still experience a clinically meaningful improvement from surgery. Patients aged >80 years are unlikely to experience a clinically meaningful improvement in DASH scores with surgical management. Older ages are associated with decreased benefits from surgical management with volar locked plating as compared to cast immobilization. Patients aged >80 years are unlikely to experience a clinically significant improvement with surgery. Surgeons and policymakers may use these data to counsel patients, health systems, and professional organizations on the risks and benefits of operative treatment in older adults. Prognosis 1, Meta-Analysis of Randomized Controlled Trials.

Cement-Augmented Screw Fixation with PHILOS Plating for Osteoporotic Proximal Humeral Fractures: An Observation of Mid- and Long-Term Curative Efficacy.

The mid- and long-term clinical outcomes of cement-augmented screws in the treatment of osteoporotic proximal humeral fractures have rarely been reported. The aim of this study was to observe the mid- and long-term efficacy of combined cement-augmented screw fixation and PHILOS plating in the treatment of osteoporotic fractures of the proximal humerus. This study retrospectively analyzed data from 19 patients with osteoporotic fractures of the proximal humerus who had undergone internal fixation at the Guizhou Provincial People's Hospital from February 2017 to May 2021. The cohort was comprised of six males and 13 females, aged 75-87 (mean age: 82.52 ± 1.24) years. According to the Neer classification, three, 12, and four patients had two-part, three-part, and four-part fractures, respectively. All patients were treated with open reduction internal fixation with cement-augmented screws and PHILOS plating. Time until fracture healing was recorded postoperatively. Patients were observed for postoperative complications, including humeral head necrosis, loosening or breaking of the augmented screws, screw perforation of the humeral head, and varus fracture displacement. Visual analog scale and Constant scores of the shoulder joint were compared 1, 3, 6, and 12 months after surgery. Scores at the most recent follow-up were used to evaluate shoulder joint function. Measured data conforming to a normal distribution were expressed as mean ± SD. Analysis of variance or rank sum tests were used for intergroup comparisons. A value of p < 0.05 was considered significant. All 19 patients followed up for 1-4 (average: 2.13 ± 0.61) years. Fractures united in all cases, with a healing time of 8-14 (average: 10.25 ± 1.72) weeks. There were no cases of humeral head necrosis, screw loosening, fractures, or perforation of the humeral head. One patient had mild varus fracture displacement with a reduced neck-shaft angle. There were significant differences in visual analog scale and Constant scores 1, 3, and 6 months after surgery (p < 0.05). The visual analog scale score was 0 at final follow-up in all cases. The Constant score of the shoulder joint was excellent, good, fair, and poor in two, 12, four, and one case, respectively, yielding an excellent and good rate of 73.68%. Cement-augmented screw fixation combined with PHILOS plating of osteoporotic proximal humeral fractures had good mid- and long-term clinical efficacy. It should be considered a new option for fracture treatment in such patients.

Ti386/TC4 clad plate manufactured by hot rolling and solution-aging treatment

Clad plate of high strength Ti386 and high plasticity TC4 is manufactured by hot rolling and solution-aging treatment. The interfacial microstructure and tensile properties of Ti386/TC4 clad plate are analyzed under different conditions. Results indicate that the clad plate subjected to 40% rolling reduction achieves a metallurgical bonding as there are no voids at Ti386/TC4 interface and the interfacial bonding strength is superior to the ultimate tensile strength (UTS) of Ti386 base (883 MPa). The microstructure of the clad plate is further refined as the rolling reduction increases to 80%, and the UTS of Ti386 increases to 921 MPa, which is still inferior to that the interface and TC4 base. After solution-aging treatment, the UTS of Ti386 is greatly improved to 1547 MPa, and the clad plate fractures at TC4 side with the UTS of 1010 MPa and elongation (δ) of 14.68%. Finally, the clad plate consisting of Ti386 with 1547 MPa UTS and TC4 with 14.68% δ is obtained with metallurgical interface.

Migration and sedimentation of proppant and its influencing factors in a visual plate fracture model

Hydraulic fracturing technology is the main method used to form high-conductivity fracture networks in unconventional oil and gas reservoirs, and the effective filling of quartz sand proppant in the fracture network is key to its successful implementation. Conventional experiments on the evaluation of sand carrying migration are mainly based on the migration and sedimentation law of a single-mesh proppant in the main fracture; the results obtained are inconsistent with the field observations. To improve our understanding of the migration and sedimentation law of the proppant in the main and branch fractures, in this study, the influences of injection time, injection rate, fracturing fluid viscosity, and proppant combination type on the migration and sedimentation law of a proppant in single and branch fractures were analyzed based on the injection parameters of the sand-carrying fracturing fluid obtained using a similarity criterion through a visual large-scale parallel-plate fracture model system built indoors. The results showed that the rapid accumulation stage of the proppant in the fracture is during the injection time of 5–10 min; the injection rate affected the accumulation area and height of the proppant to a certain extent but had little effect on the final sand dike morphology. A low viscosity of the fracturing fluid was not conducive to the sedimentation of the proppant in the branch fractures; an excessively high fracturing fluid viscosity was not conducive to the sedimentation of the proppant in both the main and branch fractures. When the fracture morphology is single, the viscosity of the fracturing fluid is recommended to be between 30 and 60 mPa·s. When the fracture morphology is complex, the recommended value is between 40 and 50 mPa s. Taking the migration and sedimentation laws of the proppant in the main fracture as an example, the flow of fracturing fluid in the fracture after the formation of a stable sand dike could be divided into five regions: ① inlet scour zone; ② buffer zone; ③ sand dike stable transition zone; ④ sand dike stability zone; and ⑤ outlet scour zone. The higher the large mesh proppant ratio used in the fracturing fluid, the lower the total area ratio of the corresponding sand dike; however, the proppant sedimentation ratio in the branch fracture increases. This study enriches and improves the relevant theoretical research on the migration and sedimentation of proppants and has a certain effect on improving the success rate of the hydraulic fracturing technology applied to unconventional oil and gas reservoirs.

A Review on Polymers for Biomedical Applications on Hard and Soft Tissues and Prosthetic Limbs.

In the past decades, there has been a significant increase in the use of polymers for biomedical applications. The global medical polymer market size was valued at USD 19.92 billion in 2022 and is expected to grow at a CAGR of 8.0% from 2023 to 2030 despite some limitations, such as cost (financial limitation), strength compared to metal plates for bone fracture, design optimization and incorporation of reinforcement. Recently, this increase has been more pronounced due to important advances in synthesis and modification techniques for the design of novel biomaterials and their behavior in vitro and in vivo. Also, modern medicine allows the use of less invasive surgeries and faster surgical sutures. Besides their use in the human body, polymer biomedical materials must have desired physical, chemical, biological, biomechanical, and degradation properties. This review summarizes the use of polymers for biomedical applications, mainly focusing on hard and soft tissues, prosthetic limbs, dental applications, and bone fracture repair. The main properties, gaps, and trends are discussed.

Medial helical versus straight lateral plating of distal femoral fractures—a biomechanical comparative study

BackgroundDistal femoral fractures are commonly treated with lateral straight plates. However, the lateral approach may not always be desirable, and 180°-helical plates may be an alternative. AimTo investigate the biomechanical competence of 180°-helical plating versus standard straight lateral plating of unstable fractures at the distal femur. MethodsTwelve left artificial femora were instrumented with a 15-hole Locking Compression Plate–Distal Femur, using either 180°-helical plates (group 1) or conventional straight lateral plates (group 2). An unstable distal femoral fracture AO/OTA 33-A3.3 was simulated. All specimens were biomechanically tested under quasi-static and progressively increasing combined cyclic axial and torsional loading in internal rotation until failure. FindingsInitial axial stiffness (N/mm) was significantly higher in group 1 (185.6 ± 50.1) compared to group 2 (56.0 ± 14.4), p < 0.001. Group 1 demonstrated significantly higher initial interfragmentary flexion (°) and significantly lower initial varus/valgus deformation (°) under 500 N static axial compression versus group 2 (2.76 ± 1.02 versus 0.87 ± 0.77 and 4.08 ± 1.49 versus 6.60 ± 0.47), p ≤ 0.005. Shear displacement (mm) under 6 Nm static torsion was significantly higher in group 1 versus group 2 in both internal (1.23 ± 0.28 versus 0.40 ± 0.42) and external (1.21 ± 0.40 versus 0.57 ± 0.33) rotation, p ≤ 0.013. Cycles to failure and failure load (N) (clinical/catastrophic) were significantly higher in group 1 (12,484 ± 2116/13,752 ± 1518 and 1748.4 ± 211.6/1875.2 ± 151.8) compared to group 2 (7853 ± 1262/9727 ± 836 and 1285.3 ± 126.2/1472.7 ± 83.6), p ≤ 0.001. InterpretationAlthough 180°-helical plating using a pre-contoured standard straight lateral plate was associated with higher shear and flexion movements, it demonstrated improved initial axial stability and resistance against varus/valgus deformation compared to straight lateral plating. Moreover, the helical plates were associated with significantly higher endurance to failure. From a biomechanical perspective, 180°-helical plating may be considered as a valuable alternative to standard straight lateral plating of unstable distal femoral fractures.

Evolution of Cementite Substructure of Rails from Hypereutectoid Steel during Operation

Transmission electron microscopy methods were used to analyze the cementite substructure in the head of special-purpose long rails of the DT400IK category, made of hypereutectoid steel, after long-term operation on an experimental track on the Russian Railways ring (the tonnage was 187 million tons). It is noted that the study of various aspects of cementite—its structure, morphology, chemical composition, crystal lattice defects—is relevant. The steel structure is represented by three morphological components at a distance of 10 mm from the sample surface: lamellar perlite, fractured and fragmented perlite. The volume fraction of lamellar perlite in the material is 65%. It is shown that after operation, the cementite plates are bent and separated by ferrite bridges. In the plates of ferrite and cementite, a dislocation substructure is formed, which is of a chaotically distributed and network type in ferrite and of an ordered type in cementite. An increased density of dislocations at the ferrite–cementite interfaces compared to the volume of ferrite plates was noted. Two possible mechanisms of deformation transformation of lamellar perlite grains are indicated: fracture of cementite plates and carbon pulling out from the lattice of the carbide phase. It is indicated that in the dissolution of cementite plates, the interfacial boundaries of “α-phase-cementite” play an important role. The removal of carbon from cementite plates occurs most intensively near defects in ferrite and cementite. The formed nanosized particles of tertiary cementite are unevenly distributed in the ferrite plates; most of them are observed at the locations of ferrite subgrains and interfacial boundaries. This results in non-uniform diffraction contrast in dark-field images of cementite plates. Nanosized particles of cementite can be taken out into the interlamellar space of pearlite colonies in the process of dislocation slip, or they are formed as a result of deformation decomposition, which is less likely. The fragmentation of ferrite and cementite plates is revealed and azimuthal components of total misorientation angles are estimated. The mechanisms of mass transfer of carbon atoms over interstitial sites, deformation vacancies, dislocation tubes, grain boundaries and fragments are considered. According to all the established patterns of the cementite substructure transformation, a comparison with the results for rails made of hypoeutectoid steel was performed.

Comparison of distal radius fracture plating surgery under wide-awake local anesthesia no tourniquet technique and balanced anesthesia: a retrospective cohort study

BackgroundDistal radius fractures (DRF) are frequently treated with internal fixation under general anesthesia or a brachial plexus block. Recently, the wide-awake local anesthesia with no tourniquet (WALANT) technique has been suggested as a method that results in higher patient satisfaction. This study aimed to evaluate the functional outcomes, complications, and patient-reported outcomes of DRF plating surgery under both the WALANT and balanced anesthesia (BA).MethodsNinety-three patients with DRFs who underwent open reduction and plating were included. Regarding the anesthetic technique, 38 patients received WALANT, while 55 received BA, comprised of multimodal pain control brachial plexus anesthesia with light general support. The patient's overall satisfaction in both groups and the intraoperative numerical rating scale of pain and anxiety (0–10) in the WALANT group were recorded. The peri-operative radiographic parameters were measured; the clinical outcomes, including Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, wrist mobility, and grip strength, were recorded in up to 1-year follow-up. Results presented with a mean difference and 95% confidence intervals and mean ± standard deviation.ResultsThe mean age of patients in the WALANT group was higher than in the BA group (63 ± 17 vs. 54 ± 17, P = 0.005), and there were fewer intra-articular DRF fractures in the WALANT group than in the BA group (AO type A/B/C: 30/3/5 vs. 26/10/19, P = 0.009). The reduction and plating quality were similar in both groups. The clinical outcomes at follow-up were comparable between the two groups, except the WALANT group had worse postoperative 3-month pronation (88% vs. 96%; − 8.0% [ − 15.7 to − 0.2%]) and 6-month pronation (92% vs. 100%; − 9.1% [ − 17.0 to − 1.2%]), and better postoperative 1-year flexion (94% vs. 82%; 12.0% [2.0–22.1%]). The overall satisfaction was comparable in the WALANT and BA groups (8.7 vs. 8.5; 0.2 [ − 0.8 to 1.2]). Patients in the WALANT group reported an injection pain scale of 1.7 ± 2.0, an intraoperative pain scale of 1.2 ± 1.9, and an intraoperative anxiety scale of 2.3 ± 2.8.ConclusionThe reduction quality, functional outcomes, and overall satisfaction were comparable between the WALANT and BA groups. With meticulous preoperative planning, the WALANT technique could be an alternative for DRF plating surgery in selected patients.Trial registration This retrospective study was approved by the Institutional Review Board of Kaohsiung Medical University Hospital (KMUHIRB-E(I)-20210201).

Cost analysis and clinical outcomes of anatomic pre-contoured locking versus conventional plates for distal fibula ankle fractures.

To analyze differences in union, complication rates and cost from surgical fixation of distal fibula fractures with fibular plating implants. In total, 380 adult patients from 2012 to 2015 treated with 12 fibular plates from 4 different manufacturers utilized by 9 surgeons were retrospectively reviewed. They were stratified into a conventional one-third tubular fibular plate group, pre-contoured anatomic locking plate group, or a heterogeneous group including 3.5-mm reconstruction, one-third tubular locking, composite, and limited compression plates. The outcomes included failure of fixation, deep infection requiring debridement, time to union, anatomic reduction, superficial infection, hardware removal, and post-traumatic arthritis. Plate and screw costs were calculated from hospital billing records. Pre-contoured locking plates were used in older, female patients with a greater number of comorbidities. Open injuries and OTA 44B fractures were more likely to be an indication for pre-contoured plates. There was no difference noted in time to union between the different plating groups. Risk factors for deep infection requiring debridement included a history of tobacco use, open fractures, and pre-contoured locking plates relative to the conventional plating group. The pre-contoured plating group was on average $586 more expensive compared to the conventional group. Pre-contoured locking plates achieved similar radiographic outcomes compared to conventional plates with an increased risk of complications and higher cost. Surgeons should consider their choice of implant based on the patient's fracture pattern, underlying comorbidities, and risk for infection.

Trauma

The October 2023 Trauma Roundup360 looks at: Intramedullary nailing versus sliding hip screw in trochanteric fracture management: the INSITE randomized clinical trial; Five-year outcomes for patients with a displaced fracture of the distal tibia; Direct anterior versus anterolateral approach in hip joint hemiarthroplasty; Proximal humerus fractures: treat them all nonoperatively?; Tranexamic acid administration by prehospital personnel; Locked plating versus nailing for proximal tibia fractures: a multicentre randomized controlled trial; A retrospective review of the rate of septic knee arthritis after retrograde femoral nailing for traumatic femoral fractures at a single academic institution.

Bridge Plating of Humerus Shaft Fractures by Minimally Invasive Plate Osteosynthesis Technique: A Short-term study

Bridge Plating of Humerus Shaft Fractures by Minimally Invasive Plate Osteosynthesis Technique: A Short-term study

Subchondral Insufficiency Fractures of the Knee: A Clinical Narrative Review.

» Subchondral insufficiency fractures of the knee (SIFKs) are subchondral plate fractures with a prevalence of 2% to 4% of all knee injuries.» Magnetic resonance imaging is the gold standard for evaluating SIFK, while plain radiographs have limited the use in the diagnosis of SIFK.» Among patients with SIFK, 50% to 100% have meniscal pathology.» Medical therapies and standard treatments traditionally used in the management of knee osteoarthritis differ from recommended management of SIFK patients.» Randomized controlled trials and cohort studies with long-term follow-up are needed to determine the optimal rehabilitation protocol, interventional therapy, and prognosis of SIFK patients.

Experimental investigation of steel beam-to-column end-plate joints under static and impact loading

Events like blasts, vehicle impacts, gas explosions, or terrorist attacks can induce dynamic structural responses. Traditional design practices focus on structures' static or quasi-static behavior, neglecting dynamic effects. However, the response of structural members and joints under dynamic loading can differ significantly from that under static loading. For instance, the mechanical properties of steel, such as yield strength and tensile strength, exhibit variations depending on the strain rate. Experimental impact load tests of members and connections are needed to validate FEM models, but a very limited number of such tests have been presented in the literature. This article presents experimental static and impact tests of double-sided extended steel bolted end-plate joints. The tests were carried out on three identical steel specimens of a beam-to-column system, with static tests on one specimen and impact tests on two other specimens. A free-falling concrete-steel package was used as the impact load, with varying values of its weight and the height of the fall. The structural responses of the joints and selected components were measured using advanced measuring equipment for experimental static and dynamic tests. In both static and impact tests, significant deformation of the connection elements, especially the column and end-plate, was observed. Moreover, local buckling appeared in the compression zone of the column web as well as fracture of the end plate below the lower flange of the beam. Based on the results of the deformation measurements, the actual strain rate and dynamic increase factor (DIF) were obtained.

Cyclic test evaluation of double skin composite hybrid coupled wall with frictional steel truss coupling beams

The seismic performance of double skin composite shear walls (DSCSWs) has significant superior to conventional reinforce concrete (RC) shear walls. Previous studies have neglected the changes of axial compressive forces and bending moments actting on the top of wall piers. In addition, behaviors hybrid coupled wall (HCW) under real boundary condition have not been fully investigated. Thus, in this study, a novel quasi-static test which incorporates the boundary conditions of substructures in a prototype building was preformed. And a cyclic test was carried out on a 2/3-scaled double skin composite (DSC) HCW with frictional steel truss coupling beams (FSTCBs) using the proposed method. The seismic behavior of specimen under reversed lateral cyclic loads was investigated. The failure modes of the wall piers mainly included local buckling of the steel faceplate, fracture of the side plate, and concrete crushing at the corners of walls. The force-displacement hysteresis curve of FSTCBs was obtainable from the attached instruments as the force transmission path of the steel truss could be clearly observed. DSCSW pier deformation was evaluated based on the deformative relationship between the wall pier and FSTCB. The FSTCB primarily dissipated 80% of the total energy input prior to damage occurring in the DSCSW. Strain distribution curves along the DSCSW showed that the pre-peak-resistance plane section assumption was still valid.

The use of precontoured plates for midshaft clavicle fractures is not always the best course of treatment.

Plate fixation has become the preferred approach for treating displaced midshaft clavicle fractures. However, plate fixation of the clavicle presents several unique challenges, including its complex bony architecture and its immediate subcutaneous location. In many cases, we have observed that precontoured implants do not conform to the clavicular anatomy, and many patients complain of postoperative implant-related discomfort. A total of 111 clavicles, both left and right sides, were examined to match two commonly used designs of anatomical pre-contoured superior anterior clavicle plates, with and without lateral extension. The anteroposterior (AP) plane congruence of the plate to the underlying bone, the vertical gap between the bone and plate, and the length of the plate that was off the bone either anteriorly and/or posteriorly at both ends of the clavicle were measured. The scoring system was used to determine the fit of the implant on the clavicle as anatomic, good, or poor. We found that the maximum superior bow of the clavicle was lateral to the midline by 30.75 mm and 30.5 mm on the right and left sides, respectively. The magnitude of the bow was 4.28 mm and 4.46 mm on the right and left sides, respectively. We also found that the plate was a poor fit in 75.86% of cases on the left side and 73.5% of cases on the right side. Manipulating the plates during surgery was very difficult in the AP plane.

Effect of lag screw and support plate through axillary approach for the treatment of Ideberg typeⅡscapular pelvis fracture

To analyze the effect of lag screw and support plate through axillary approach for the treatment of Ideberg typeⅡscapular pelvis fracture. From January 2016 to June 2021, 26 patients with Ideberg typeⅡglenoid fractures were treated with trans-axillary lag screw combined with supporting plate, including 15 males and 11 females. The age ranged from 21 to 75 years, with an average of (43.12±6.56) years old. The Constant-Murley Shoulder joint Scale and University of California at Los Angeles (UCLA) score were used to evaluate the function and clinical efficacy of shoulder joint. All patients were followed up, and the duration ranged from 19 to 42 months, with an average of (30.6±10.5) months. One year after surgery, the Constant-Murley score increased from preoperative 34.9±2.5(ranged, from 28 to 47) to 87.2±6.8(ranged, from 70 to 95). The UCLA score improved from preoperative 17.9±1.7(9 to 25) to 33.1±2.3(29 to 35). Seventeen patients got an excellent result, with 7 good, and 2 fair. None of the patients had infection, screw, and plate loosening, fracture, and other complications after surgery. Two patients had different degrees of Chronic pain in the shoulder during the follow-up period. The treatment of Ideberg typeⅡscapular glenoid fractures through axillary approach with lag screws and supporting steel plates has the advantages of convenient exposure, direct visual restoration of the normal anatomical shape of the scapular glenoid, selection of suitable positions for screw and steel plate placement, achieving better treatment results, and fewer complications. It is an effective and reliable surgical method.

Inclined angles of acetabular quadrilateral plate: digital measurement and clinical application of the new anatomical concept

PurposeMatta scoring standard is one of the most frequently used postoperative imaging evaluations for acetabular fracture reduction, but has obvious shortcomings. This study, for the first time, proposed the concept of inclined angles of acetabular quadrilateral plate. The purpose of this study was to investigate the normal range of the inclined angles in adults by digital measurement and explore the feasibility of using them to evaluate the reduction quality of acetabular quadrilateral fractures after surgery.MethodsFirstly, the pelvic CT three-dimensional reconstruction data of 40 healthy adults including 20 males and 20 females were collected. The normal range of the anterior, middle, and posterior inclined angles were measured via Mimics software. Secondly, a modified Matta criteria that combined the classic Matta criteria and evaluation criteria of the inclined angles was proposed. And we classified modified Matta criteria into three grades including excellent, good and poor. Finally, a total of 125 cases with quadrilateral plate fractures was included and the postoperative CT data were analyzed by using both the classic Matta criteria and our modified Matta criteria. Then, the accuracy and consistency of both criteria to evaluate postoperative hip function was investigated.ResultsThe average anterior inclined angle: male (97.11° ± 2.59°), female (90.63° ± 2.09°); middle inclined angle: male (105.57° ± 1.93°), female (100.64° ± 2.46°); and posterior inclined angle: male (112.62° ± 2.54), female (106.37° ± 2.53°). Whether in males or in females, the anterior, middle, and posterior inclined angles showed a progressively increasing trend. All the three inclined angles in males were all significantly larger than those in females (p < 0.05). Among 125 cases with quadrilateral plate fractures, 101 cases (80.8%) were graded as excellent, 18 cases (14.4%) as good, and 6 cases (4.8%) as poor according to the classic Matta criteria. While based on modified Matta criteria, there were excellent in 37 cases (29.6%), good in 76 cases (60.8%), and poor in 12 cases (9.6%). According to the Harris hip score system, the functional outcomes were excellent in 59 cases (47.2%), good in 26 cases (20.8%), fair in 24 cases (19.2%), and poor in 16 cases (12.8%). Our results showed that among the cases evaluated as excellent according to the classic Matta criteria and modified Matta criteria, the excellent-to-good rates of hip function were 70.3% and 78.4%, respectively. And among the cases evaluated as poor according to the modified Matta criteria, the fair-to-poor rate of hip function was 75%, while this value was 50% for classic Matta criteria. Both differences were statistically significant (p < 0.05).ConclusionInclined angles of the quadrilateral plate could be used to assess the quality of fracture reduction and provide a basis for evaluating the rotational displacement of fracture blocks in the quadrilateral plate, which compensates the shortage of classic Matta criteria.