Stability Of Plates Research Articles

Buckling and post-buckling of anisogrid lattice-core sandwich plates with nanocomposite skins

This research offers an in-depth examination of the buckling and post-buckling responses observed in sandwich plates distinguished by the presence of an anisogrid lattice core and face layers composed of functionally graded carbon nanotube-reinforced composites (FG-CNTRC). To model this structure, a global continuous model for the lattice core is employed, while the displacement field is approximated using the First-Order Shear Deformation Theory (FSDT). Geometrically nonlinear strain relations based on the von-Kármán assumptions are incorporated to accurately capture the structural response. The homogenization of the FG-CNTRC skins is achieved through the modified rule of mixture, enabling estimations of effective material properties. To separate pre-buckling and post-buckling phases, we implement the adjacent-equilibrium criterion. Solving the linear (pertaining to buckling) and nonlinear (related to post-buckling) equations is based on the Generalized Differential Quadrature (GDQ) technique alongside an iterative method grounded in the displacement control strategy. Our analysis explores the influence of core and skin characteristics on the stability of these sandwich plates. By examining critical buckling thresholds, post-buckling equilibrium paths, and the underlying mechanisms driving these responses, we contribute insights into the structural stability and performance of such composite structures. This study not only enhances our understanding of buckling behavior in anisogrid lattice core sandwich plates but also holds promise for diverse engineering applications where structural stability is paramount.

The associations between lumbar proprioception and postural control during and after calf vibration in people with and without chronic low back pain.

The relationships of lumbar proprioception with postural control have not been clarified in people with chronic low back pain. This study aimed to compare the associations between lumbar proprioception and postural control in response to calf vibration in individuals with and without chronic low back pain. In this study, we recruited twenty patients with chronic low back pain (CLBP group) and twenty healthy control subjects (HC group) aged between 18 and 50 years. This study was a cross-sectional study and completed from May 2022 to October 2022. The passive joint repositioning sense (PJRS) test for two positions (15° and 35°) were used to assess lumbar proprioception and expressed as the mean of reposition error (RE). Postural control was tested by adding and removing calf vibration while standing on a stable force plate with eyes closed. The sway velocity in the anterior-posterior (AP) direction of center of pressure (COP) data with a window of 15s epoch at baseline, during and after calf vibration was used to evaluate postural control. Mann-Whitney U-tests were used to compare the difference of lumbar proprioception between two groups, and the independent t-tests were used to compare the difference of postural control at baseline and during vibration, and a mixed design ANOVA was used to compare the difference of postural control during post-perturbation. In addition, to explore the association between postural control and lumbar proprioception and pain intensity, Spearman's correlations were used for each group. The major results are: (1) significantly higher PJRS on RE of 15° (CLBP: 95% CI [2.03, 3.70]; HC: 95% CI [1.03, 1.93]) and PJRS on RE of 35° (CLBP: 95% CI [2.59, 4.88]; HC: 95% CI [1.07, 3.00]) were found in the CLBP group; (2) AP velocity was not different between the CLBP group and the HC group at baseline and during calf vibration. However, AP velocity was significantly larger in the CLBP group compared with the HC group at epoch 2-14 after calf vibration, and AP velocity for the CLBP group took a longer time (23 epochs) to return to the baseline after calf vibration compared with the HC group (9 epochs); (3) lumbar proprioception represented by PJRS on RE of 15°correlated negatively with AP velocity during and after vibration for the HC group. Within the CLBP group, no significant relationships between PJRS on RE for two positions (15° and 35°) and AP velocity in any postural phases were found. In conclusion, the CLBP group has poorer lumbar proprioception, slower proprioceptive reweighting and impaired postural control after calf vibration compared to the HC group. Lumbar proprioception offers different information on the control strategy of standing control for individuals with and without CLBP in the situations with proprioceptive disturbance. These results highlight the significance of assessing lumbar proprioception and postural control in CLBP patients.

The nonlinear instability of transverse vibration behavior of functionally graded materials sandwich rectangular plates of under a harmonic loading and subsonic flow

This work is devoted to studying the combined action of periodic in-plane load and tangential subsonic flow on the nonlinear mechanism of the out-plane deformation of the functionally graded composite plate. Three distribution functions are proposed to investigate the distribution of the transverse shear strains and stresses across the thickness of the plates. By using Hamilton’s variational principle, the equations governing the plate instability boundaries are formulated. A nonlinear differential equation describing the first mode of the plate dynamic instability behavior by employing Galerkin’s method. The method of multiple time scales is used to obtain a periodic one-mode solution, which directly leads to the solvability condition. The different resonance cases for the interaction between the frequency of out- plane deformation and the external forces are discussed to discover the extent of the sandwich functionally graded material (FGM) rectangular plate resistance in the presence of external influences. Various bifurcation diagrams for different cases of resonance are obtained versus the basic parameters. In view of this study, we could get a deeper look at the complexity of frequency components in resonance responses of the sandwich FGM rectangular plate. The results could provide some suggestions for the sandwich plate’s vibration reduction design or fault diagnosis field or design fault diagnosis.

A Feasibility Test of the Disposable Drug Daughter Plate Combined with 384‐Pillar Plate for Patient‐Derived Organoid‐Based High Throughput Screening

AbstractA disposable daughter plate is developed for robotic organoid‐based high‐throughput screening (HTS). Previously, daughter drug plates are prepared using mother drug plates in conventional HTS. During each screening, the mother drug plate is thawed, a certain amount of the drug is transferred to the daughter plate, and frozen again. Drug manufacturing involves drug transfer processes that may result in drug damage owing to redissolution. Thus, disposable daughter plates are created by dispensing small drug spots into the well plates and freezing them. The cells at the Matrigel dorms of the pillar plate are easily exposed to the drugs by immersing the pillars. Unlike previously reported similar methods, it is verified that HTS‐based drug response analysis is possible by applying the proposed disposable daughter plate to breast cancer patient‐derived organoids (PDOs). And it is also verified the long‐term stability of disposable daughter plates (up to 3 months) in 3D cell culture system using patient‐derived cells (PDO). The drug response results are quantified using normalized area under curve values, while the experimental reproducibility of the disposable daughter plates is evaluated using the coefficient of variation and a simple linear regression test. Thus, the proposed disposable daughter plate allows reproducible drug efficacy analysis.

Aero-thermal stability and nonlinear vibration analysis of a thin plate in narrow channel

Aero-thermal stability and nonlinear vibration analysis of a thin plate in narrow channel

Study on Influence of Tension Height of Steel Strand on Displacement of Foundation Pit Supported by Fish-bellied beams

The steel support system of prestressed fish-bellied beams can reliably control the deformation of foundation pit and provide open excavation space for foundation pit excavation, in which the triangle plate plays an important role in the fish-bellied beams system. But the deformation of the triangle plate and the steel strand is too large is a common problem in the foundation pit support, through the analysis of the stability of the triangle plate, it is found that the tension point height is an important factor leading to the deformation of too large. Through MIDAS/GEN analysis, it is found that the increase of the tension point height of the strand is conducive to the control of the displacement of the connecting part, and with the increase of the tension point of the strand, the anti-impact stability of the fish-bellied beams system is gradually enhanced. Therefore, by changing the tension height of the steel strand, the supporting system of the fish-bellied beams is optimized.

Black blow fly (Diptera: Calliphoridae) bacterial symbionts inform oviposition site selection by stable flies (Diptera: Muscidae).

Larval habitats of blood-feeding stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), overlap with foraging sites of black blow flies, Phormia regina (Meigen) (Diptera: Calliphoridae). We tested the hypothesis that bacteria in blow fly excreta inform oviposition decisions by female stable flies. In laboratory 2-choice bioassays, we offered gravid female stable flies fabric-covered agar plates as oviposition sites that were kept sterile or inoculated with either a blend of 7 bacterial strains isolated from blow fly excreta (7-isolate-blend) or individual bacterial isolates from that blend. The 7-isolate-blend deterred oviposition by female stable flies, as did either of 2 strains of Morganella morganii subsp. sibonii. Conversely, Exiguobacterium sp. and Serratia marcescens each prompted oviposition by flies. The flies' oviposition decisions appear to be guided by bacteria-derived semiochemicals as the bacteria could not be physically accessed. Oviposition deterrence caused by semiochemicals of the 7-isolate-blend may help stable flies avoid competition with blow flies. The semiochemicals of bioactive bacterial strains could be developed as trap lures to attract and capture flies and deter their oviposition in select larval habitats.

Comparison of exposure of the radius afforded by the craniomedial and craniolateral open surgical approaches in dog cadavers.

Management of antebrachial fractures in dogs typically involves open reduction and bone plate stabilisation of the radius performed using either a craniomedial approach (CMA) or craniolateral approach (CLA). The aim of this cadaveric study was to compare radial exposure afforded via the craniomedial and craniolateral approaches, without and with releasing the abductor digiti I longus (ADIL) muscle. The CMA and CLA were performed on alternate paired cadaver forelimbs with the subsequent release (CMA) or elevation (CLA) of the ADIL muscle (n = 12). The percent area of exposure was calculated in defined longitudinal radial segments (LRSs) and hemi-circumferential radial segments (HRSs) using digitally uploaded images. A non-parametric rank sum test was used for statistical analysis (p < 0.05). While both the CMA and CLA provided sufficient exposure for radial cranial plate placement in the mid-to-distal diaphyseal region (50-80% LRSs), the CMA afforded greater exposure to the distal metaphysis (80-90% LRS). The CLA was advantageous in exposing the proximal diaphysis (20-50% LRSs) and distal epiphysis (90-100% LRS). Exposure of the distal diaphyseal, metaphyseal, and epiphyseal regions (80-100% LRSs) was impeded by the ADIL muscle. A tenotomy of the tendon of insertion of the ADIL muscle increased exposure afforded by the CMA in the distal metaphyseal and epiphyseal regions. The exposure afforded by the CLA in the distal diaphyseal and metaphyseal regions was significantly improved by elevating the origin of the ADIL muscle. The results of this study provide useful clinical information when surgeons are deciding which approach to use for cranial radial plating.

Comparative Outcomes of Elastic Stable Intramedullary Nailing vs. Plate Fixation in Pediatric Femoral Shaft Fractures. A Prospective Study.

Pediatric femoral fractures are common in emergency rooms, with treatment options varying by age. This study compares elastic stable intramedullary nailing (ESIN) and plate fixation for diaphyseal femoral fractures in children aged 5-10. Conducted at Al-Kindi Teaching Hospital, Baghdad, from December 2017 to December 2019, this prospective study included 32 children with closed transverse diaphyseal femoral fractures. Patients were divided into two groups: 16 treated with ESIN (Group 1) and 16 with plate fixation (Group 2). Criteria excluded comminuted, open, or pathological fractures. Group 1 had a mean age of 7.1 years and weight of 23.7 kg; Group 2 had a mean age of 7.8 years and weight of 30.9 kg. ESIN resulted in shorter operative times (58.4 minutes), earlier weight-bearing, and quicker fracture union (8.8 weeks) compared to plate fixation (76.3 minutes, 11.9 weeks). Blood loss was significantly less in Group 1 (32.8 ml) versus Group 2 (205.0 ml). No significant differences in wound healing or leg length discrepancies were observed. 1. Our study indicates a preference for Elastic Stable Intramedullary Nailing (ESIN) over plate fixation for pediatric femoral shaft fractures in children aged 5-10 years. 2. ESIN is associated with shorter operative times and faster commencement of weight-bearing, critical in pediatric recovery. 3. While ESIN is generally preferable, plate fixation may be better suited in certain clinical scenarios, emphasizing the importance of personalized treatment. 4. Based on our findings, ESIN is recommended for treating transverse diaphyseal femur fractures in the specified pediatric age group. 5. Recommends further studies, including randomized controlled trials, for a more comprehensive understanding of these treatments' long-term outcomes.

Seismological Constraints on the Causes of Intraplate Earthquakes in Yangjiang Region, South China

AbstractLarge earthquakes that occur away from plate boundaries (i.e., large intraplate earthquakes), though rare, could cause heavy damage. Understanding their causes could help with seismic hazard assessment. In this study, we image the seismogenic structure under the 1969 Ms6.4 Yangjiang intraplate earthquake within the stable South China Block with a high‐resolution three‐dimensional shear‐wave velocity model constructed from ambient noise tomography based on a dense nodal seismic array. The model images relatively low velocities at a fault intersection region from the surface to at least 13 km depth in the Yangjiang seismogenic zone. Given spatial links among the intersection zone of faults, surface seawater, and low velocities, we interpret the low velocities to reflect the presence of seawater‐filled, highly fractured rocks created by the intersection of faults. We infer that the seawater infiltration through densely‐fractures could have elevated pore pressure in the long term, as evidenced by low earthquake b values at 8–13 km depths. We hypothesize that this long‐term seawater infiltration could have lowered the stress threshold of earthquake occurrence and contributed to the generation of the 1969 Ms6.4 Yangjiang earthquake. We propose that the large intraplate earthquakes within stable plates tend to occur in regional weakening regions (e.g., fault intersections) favorable to stress buildup. Given sufficient tectonic stress accumulation, the long‐term hydrologically driven crustal stress variations could play an essential role in triggering large intraplate earthquakes. This study could potentially contribute to improving seismic hazard assessment in the Guangdong‐Hong Kong‐Macao‐Greater‐Bay‐Area, China.

Enhancing stability of microchannel plates (MCPs) through freeze-drying method

The crystallization and gain decrease of microchannel plates (MCPs) have a significant impact on the dark noise and working life of optoelectronic devices. By employing a freeze-drying method instead of high-temperature drying during MCP manufacturing, stability can be improved. Freeze-drying at low temperatures (−100 °C) mitigates chemical reactions between potassium (K) and oxygen (O2) or water (H2O) in the secondary emission layer, reducing crystallization during production and storage. Furthermore, freeze-drying eliminates the need for organic solvents, which can lead to carbon (C) element pollution on the MCP surface. Minimizing C element pollution is beneficial in reducing unstable “gas gain” and attenuating MCP gain during electron scrubing. Long-term storage tests demonstrate that freeze-dried MCPs exhibit over 20% reduction in crystallization and more than 10% decrease in gain loss rates. These findings highlight freeze-drying as an effective approach to enhance MCP stability, resulting in photomultiplier tubes (PMTs) with lower dark counting rates and higher gains.

Analysis of the Effect of an Open Hole on the Buckling of a Compressed Composite Plate.

This paper investigates the effect of an open hole on the stability of a compressed laminated composite plate. The study was carried out in two ways: using experimental tests and numerical analysis. As a result of the experiment, the buckling form and path of the plate were recorded. The form of buckling was determined using the ARAMIS non-contact measurement system. The critical load value was determined from the working path using the approximation method. The experimental results were verified by numerical analysis based on the finite element method. FEM investigations were carried out in terms of a linear eigenproblem analysis. This allowed the bifurcation load and the corresponding buckling form of the numerical model of the plate to be determined. Investigating the effect of the hole in the compressed plate at a critical state showed high agreement between the proposed test methods. No clear effect of the hole size on the buckling of the plate was observed. In contrast, a clear effect of the hole on the critical load value was determined. The maximum decrease in the critical load value was 14%. The same decrease was observed for the stiffness of the post-critical characteristics. It was shown that the [45|-45|90|0]s composite plate had more than three times lower strength compared to [0|-45|45|90]s and [0|90|0|90]s. The novelty of this article is the development of a research methodology based on new interdisciplinary research methods for describing the influence of the central hole on the stability of compressed composite plates. The ABAQUS system was used for the numerical analysis.

Reliability of preoperative conventional X-ray diagnostics for multifragmentary midclavicular fractures - a retrospective cohort study.

The aim of this study was to evaluate the reliability of assessing preoperative conventional X-ray diagnostics in determining whether a comminuted clavicle fracture is present. A total of 326 patients with complete clinical and radiological documentation treated for a central clavicle fracture at the author's department between January 1, 2012, and June 30, 2023, were included. Among these, 73 were female, and 253 were male in a mean age of 37.5 ± 17years. On preoperative X-ray images or operation reports, 109 (33%) or 78 (24%) simple and 217 (67%) or 248 (76%) comminuted fractures were identified. Thity-one out of 248 comminuted fractures were only discovered intraoperatively, accounting for 13%. According to the AO classification on preoperative X-ray or operation reports, 109 or 78 fractures were classified as type A (33% or 24%), 51 or 45 as type B (16% or 14%), and 166 or 203 as type C (51% or 62%). For 40 patients, the discrepancy between the preoperative X-ray and the intraoperative fracture type led to a change in the surgical procedure. This represents 12% of the total cohort or 91% of the fractures that were classified differently preoperatively compared to intraoperatively. In these cases, fractures were treated with open reduction and angular stable plate osteosynthesis instead of the preoperatively planned elastic stable intramedullary nailing (ESIN). The results of this study suggest that conventional X-ray diagnostics may not always detect comminuted clavicle shaft fractures. The treating physician should be aware of this issue.

Elastic Buckling Behavior of Functionally Graded Material Thin Skew Plates with Circular Openings

This study investigates the elastic buckling behavior of Functionally Graded Material (FGM) thin skew plates featuring a circular opening. FGMs, known for their unique property gradients, have gained prominence in structural engineering due to their mechanical performance and durability. Including a circular opening introduces a critical geometric consideration, influencing the structural stability and load-carrying capacity of FGM plates. The study examines the effects of the skew angle, plate’s aspect ratio, opening position, and size on the critical buckling load, normalized buckling load, and various buckling failure modes through computer modeling and finite element analysis. The results offer valuable insights into the interplay between material heterogeneity, geometric configuration, and structural stability. For instance, the critical buckling load increases by 29%, 82%, and 194% with an increment in skew angle from 0° to 30°, 45°, and 60°, respectively. Moreover, as the opening shifts from the plate’s edge closer to the center, the critical buckling load decreases by 26%. The critical buckling load is also dependent on the power index, as an increase in the power index from 0.2 to 5 reduced the buckling load by 1698 kN. This research contributes to the advancement of our understanding of FGM thin plates’ behavior under skew loading conditions, with implications for the design and optimization of innovative structures. The findings presented provide a foundation for further exploration of advanced composite materials and their applications in structural engineering.

Comprehensive analysis of bio-inspired laminated composites plates using a quasi-3D theory and higher order FE models

A comprehensive study is carried out by employing various finite element models (FEMs) for the bending, buckling stability and free vibration analyses of bio-inspired helicoidal composite plates with various lamination schemes. A higher order quasi-3D kinematic plate theory is developed to include a shear deformation effect. The variational formulation of the problem is exploited to derive the equations of motion, element stiffness, geometrical stiffness, and mass matrices based on a non-conforming rectangular element. Three different finite elements models are derived based on non-conforming elements with different number of nodes and degree of freedom. The developed finite element model has been validated with those found in the open literature. The effects of boundary condition, lamination scheme, orthotropy ratio and aspect ratio on the mechanical response of the bio-inspired helicoidal composite plates are examined. Notably, for the lamination schemes investigated in this study, no shear locking phenomenon was observed in the analyses conducted using these FEMs. Dimensionless centre deflections, critical buckling loads and fundamental frequencies of bio-inspired helicoidal composite plates vary depending on the type of lamination scheme, boundary condition and aspect ratio. The new orientation schemes can replace the traditional ones to overcome the shear singularity and overcome the delamination defects.

Valgising angular stable plate fixation in the treatment of multifragmentary proximal humeral fractures in elderly patients.

The frequency of proximal humeral fractures shows an increasing tendency, especially in the elderly, who are frequently affected by osteoporosis. The adequate treatment of complex, displaced fractures poses a serious challenge. Among surgical treatment options, osteosynthesis with an angular stable plate is preferred, however, the implant-related complication rate may be exceptionally high. In our present study, we report the short-term outcomes of our new method of valgising angular stable plate fixation which we use for multifragmentary, displaced proximal humeral fractures in elderly patients. We retrospectively evaluated the clinical and radiological outcomes of 52 patients (46 female and 6 male, age: 71.9 ± 9.6) who suffered dislocated three- or four-part fractures and underwent valgising angular stable plate fixation. Mean follow-up time was 17.3months, while the functional outcomes were as following: excellent in 26, good in 18, moderate in 5 and poor in 3 patients. The mean Constant-Murley Score was 82.5 ± 11.2. Functional outcomes only showed significant correlation (p = 0.031) with age and were proven unrelated to fracture type, BMI and known primary diseases. The cumulative complication rate was 9.6% and revision rate was 5.8%. Neurological deficit, pseudoarthrosis or avascular humeral head necrosis did not occur during the follow-up period. Valgising angular stable plate fixation that we apply for proximal humeral fractures provided favourable functional outcomes and a low postoperative complication rate due to the optimal head and plate placement. The method is especially effective for the treatment of displaced three- and four-part fractures with weakened, osteoporotic bone structure.

Geochemistry of the North Gondwana Paleozoic Araba and Naqus formation siliciclastics, Sinai: implications for provenance, paleoweathering, and tectonic setting

ABSTRACT The Araba and Naqus formations in Ras Milan, Sinai, constitute part of the major continuous Paleozoic clastic belt stretching across northern Gondwana. They are sandstone-dominated successions, resting on Precambrian granitic basement, with lowermost thin basal polymictic conglomerate deposits (1–2 m), marking the unconformity. The Araba Formation section is composed mainly of varicoloured violet to reddish brown, fine to coarse-grained laminated and planner and overturned cross-bedded sandstones, while the overlying Naqus Formation is characterized by chaotically distributed poorly sorted quartz pebbles to cobbles within a moderately-sorted coarse- to medium-grained quartz arenite and by abundance and variety of large-scale tabular and trough cross bedding. Modal QFL classification of Araba and Naqus formation sandstones revealed that they are merely quartzose sandstones (quartz arenites). Geochemistry of the succession shows extremely wide compositional ranges for almost all major elements, but the Araba Formation is relatively enriched in SiO2, TiO2, Fe2O3*, Na2O, P2O5, and depleted in Al2O3, MgO, CaO and K2O relative to Naqus Formation. Only the Araba Formation samples are depleted in the transition elements Ni, Cr and Co and oppositely possess extreme enrichment in the HFSEs (i.e. Zr, Hf, Y, Nb, Ta, Th, U), whereas both formations show variable depletion in the LILE Rb, K and Ba, and excessive REE abundances relative to the PAAS and UCC, and LREE-enriched patterns with marked negative Eu anomalies. The provenance of the Naqus and Araba formations could be an earlier felsic magmatic source, which has undergone extensive sedimentary recycling. They possess high compositional maturity and were subjected to intensive to moderate weathering during humid climatic conditions. Passive margin tectonic setting is implied which denotes the derivation of Araba and Naqus formation siliciclastics from stable continental regions or plate interiors and deposition in intracratonic basins.

Gravity-induced seismicity modulation on planetary bodies and their natural satellites

Ground-based monitoring of seismicity and modulation by external forces in the field of planetary seismology remains equivocal due to the lack of natural observations. Constrained by the natural observations (including Earthquakes, Moonquakes, and Marsquakes) and theoretical models, we present the variation in gravitational acceleration “g” of different solar system objects, combined with external harmonic forcings that are responsible for seismicity modulation on the planetary bodies and their natural satellites. From the global diversity in seismicity modulation, it has been observed that the plate-boundary regions on the Earth exhibit both short and long-period seismicity modulation. In contrast, the stable plate interior regions appear to be more sensitive to long-period seismicity modulation, however, lacking in short-period modulation. The deep Moonquakes are susceptible for both the lunar tidal period (13.6 days and 27 days) and long-period pole wobble modulation (206 days), whereas shallow emergent type moonquakes show a seismic periodicity at the lunation period (29.5 days). Further, the seasonal variation with an annual seismicity burst and seismic periodicity at polar wobble periods for high-frequency Marsquakes captured by InSight lander indicate a natural origin. Whereas diurnal and semi-diurnal periodicity along with Phobos’ tidal period, indicate possible artifacts due to different detection probabilities and non-seismic noise in the Martian environment. We argue that, in the context of rate-state-dependent fault friction, the gravity-induced resonance destabilization model appears to be better agreement with the contrast and relative diversity in seismicity modulation linked to the Earth, Moon, and Mars.

Solving the problem of switching from one track gauge to another in the context of the requirements of interoperability specifications for classical infrastructure

The article discusses issues related to solving the problem of switching from one gauge to another. A progressive solution to the problem of different track gauges is the use of a combined gauge design. The combined track solves the problems of overloading, downtime, and wheel set problems. The design of the combined gauge has set new challenges for track infrastructure workers and scientists. The first task is the strength of the combined track structure. The second task is the stability of the combined track plates. The third task is to lay switches in the combined track and determine the permissible train speeds.

Biomechanical comparison of rotational stability of long and short plates in fixation of high tibial osteotomies in the surgical treatment of osteoarthritis

Biomechanical comparison of rotational stability of long and short plates in fixation of high tibial osteotomies in the surgical treatment of osteoarthritis