Socket Joint Research Articles

Investigation of Functionally Graded Adherents on Failure of Socket Joint of FRP Composite Tubes.

Fiber-reinforced polymer (FRP) matrix materials are quickly being investigated for application in concrete construction repair, reinforcement, and refurbishment. The technology has progressed to the point that its future acceptance is mainly reliant on the availability of established design guidelines based on recognized performance criteria, as well as the cost competitiveness of these technologies in contrast to conventional rehabilitation methods. The goal of this study is to evaluate the different functional grades of adhesives throughout bond length for bonded socket joints of laminated FRP composite pipes. Damage development resistance is high with a functionally graded FRP composite socket joint, as shown. To extend the service life of the structure, the joint designer should use an FRP composite socket joint with a functionally graded adhesive (FGA).

Modeling intervertebral articulation: The rotule à doigt mechanical joint (RAD) in birds and mammals.

The vertebrate skeleton is composed of articulated bones. Most of the articulations are classically described using mechanical joints, except the intervertebral joint. The aim of this study was to identify a joint model with the same mechanical features as the cervical joints. On the neck vertebrae, six articular surfaces participate in the joint: the cranial part of the centrum and the facets of the two prezygapophyses of a vertebra articulate on the caudal part of the centrum and the two articular facets of the postzygapophyses of the previous vertebra. We used the intervertebral joints of the birds neck to identify the mechanical joint representing intervertebral linkage. This link was described in the literature as a joint allowing two or three rotations and no translation. These features correspond to the rotule à doigt (RAD) joint, a ball and socket joint with a pin. We compared the RAD joint to the postaxial intervertebral joints of the avian neck and found it a suitable model to determine the geometrical features involved in the joint mobility. The difference in the angles of virtual axes linking the geometrical center of the centrum to the zygapophysis surfaces determines the mean dorsoventral flexion of the joint. It also helps to limit longitudinal rotation. The orientation of the zygapophysis surfaces determines the range of motion in both dorsoventral and lateral flexion. The overall system prevents dislocation. The model was validated on 13 joints of a vulture neck and 11 joints of a swallow neck and on one joint (C6-C7) in each of three mammal species: the wolf (Canis lupus), mole (Talpa europaea), and human (Homo sapiens). The RAD mechanical joint was found in all vertebral articulations. This validation of the model on different species shows that the RAD intervertebral joint model makes it possible to extract the parameters that guide and limit the mobility of the cervical spine from the complex shape of the vertebrae and to compare them in interspecific studies.

Research on Waterproof Performance of Prefabricated Utility Tunnel with Different Types of Joints

In the waterproof system of prefabricated utility tunnel, rubber gasket is usually used at the joint of adjacent pipes. The waterproofing effect of prefabricated utility tunnel joint is mostly judged by the field water injection test and the practical effect of former project. In this paper, the finite element software ANSYS is used to carry out the finite element simulation for three types of joint waterproofing of prefabricated utility tunnel. Considering the uneven settlement of utility tunnel foundation, the influence of different staggered joint installation spacing on the waterproofing of the joints is analyzed. Thus, suggestions are provided for the selection of utility tunnel joint. For the prefabricated utility tunnel with side+end face and double-side joint waterproof type, the longitudinal distance between socket joints should be constrained within 3mm after the joint is installed. It is suggested that the end face+side joint waterproof type should be used for the collapsible foundation, and the longitudinal displacement of the control socket and socket should be less than 3mm. For non-collapsible and settled foundation, double-end joint waterproof type or side+end joint waterproof type can be selected.

Shoulder Implant Manufacturer Detection by Using Deep Learning: Proposed Channel Selection Layer

Total Shoulder Arthroplasty (TSA) is the process of replacing the damaged ball and socket joint in the shoulder with a prosthesis made with polyethylene and metal components. After this procedure, intervention may be required as a result of damage to the prosthesis, except for the need for an examination regarding the prosthesis at certain periods. If the patient does not have information about the model and manufacturer of the prosthesis, the treatment process is delayed. Artificial intelligence-assisted systems can speed up the treatment process by classifying the manufacturer and model of the prosthesis. In this study, artificial intelligence methods were applied to classify shoulder implants using X-ray images. The model and manufacturer of the prosthesis is detected by using the proposed deep learning method. Besides, the most commonly used machine learning classifiers were applied for the same problem to compare the results and show the effectiveness of the proposed method. In addition, the accuracy and precision analysis and measurements of the processing times for the applied methods were performed to reveal the performance, accuracy, and efficiency of the study. In order to measure the performance of the proposed method, it was compared with studies on the same problem in the literature. As a result of the comparison, it was found that the proposed method, with an accuracy rate of 97.2%, performed better than the other studies. In the study, the implant manufacturer and model are classified in order to carry out the implant surgery process in the best way with the proposed deep learning model. With the success of the proposed system, the applicability of this model in similar prosthesis classifications has been shown. Differently from the studies in the literature, the channel selection formula is presented in the proposed deep learning method recommended for selecting the most distinctive feature filters.

Functional Evaluation of a Novel Multi-Axial Alveolar Distractor—Preliminary In Vivo Animal Study

This study evaluates the biomechanical performance of a new multi-axial alveolar distractor using an animal study. The multi-axial alveolar distractor is designed with a ball and socket joint mechanism that can rotate up to 60° toward the buccal/lingual and mesial/distal sides intra-operatively to achieve vector control. The transport segment can be moved through activating the transport screw with 0.25 pitch, allowing 13 mm in distraction height. This distractor was fixed at the right angulus mandibular of experimental rabbits and adjusted 15° toward the mesial side and 25° toward the buccal side as Group TMB (toward mesial-buccal) (n = 3), and 15° toward the mesial side as Group TM (toward mesial) (n = 3). Group TC (control) was the control group. The distractors were activated 1 mm/day for 13 days. Living bone growth was observed at various periods. The total bone growth length at the angulus region and buccal side distraction thickness after distraction were calculated. The variations in bone growth geometric shape at the mandible angulus were also recorded. Fracture testing was performed to understand the variations in the mechanical strength between the distracted and intact bone specimens. The digital radiography results showed that the osteotomy areas at the mandible angulus were healed and the bone growth completed after surgery. The average bone growth length of Group TMB was 17.68 mm. This was greater than that of Group TM at 14.79 mm. The corresponding buccal side distractor thicknesses for Group TMB and TM after distraction were 5.12 ± 0.52 mm and 3.32 ± 0.37 mm, respectively. The tensile strengths of the bone specimens after distraction of Groups TMB, TM and TC were 172.13 N, 119.27 N and 304.24 N, respectively, and the percentage of distraction bone tensile strength to normal bone was 57% and 39% for Groups TMB and TM, respectively. This study concluded that this new multi-axial alveolar bone distractor can drive bones to grow in accordance with the direction/angle of the distraction plan. The bone growth healed gradually and presented insufficient mechanical strength.

Understanding the physical examination of the shoulder: a narrative review.

The shoulder joint is a ball and socket joint which provides an extensive range of motion. Shoulder pain and weakness are common complaints among patients, which can lead to disability and affect a person's ability to perform daily activities. Shoulder pain and weakness may be associated with shoulder conditions such as rotator cuff disorders adhesive capsulitis, superior labrum anterior to posterior lesions, lesions in the biceps, acromioclavicular joint disease, or instability. Often, a thorough understanding of the network of bony, ligamentous, muscular, and neurovascular anatomy is required to properly identify and diagnose shoulder pathology. Identifying a specific shoulder pathology may be challenging, considering the numerous structures involved in shoulder function. Appropriate physical examination of the shoulder is important for making an accurate diagnosis and distinguishing certain pathologies of the shoulder. Evaluation of shoulder problem may be reliant upon physical examination, which involves inspection, palpation, assessment of range of motion, strength, and neurovascular integrity. In addition, specific tests are used to reproduce symptoms and signs that would help physicians identify the pathology of the shoulder problem. The aim of this study was to review the shoulder anatomy and describe the specific tests used to evaluate common shoulder conditions to facilitate accurate diagnosis and guide proper treatment of these conditions.

Integrative management of recurrent anterior shoulder dislocation

Introduction: Shoulder joint is the most mobile ball and socket joint. It allows movement along three planes due to its bony configuration and loose joint capsule. Stability of shoulder joint mainly depends on muscle strength supporting the joint. Shoulder dislocation is common injury; anterior dislocation being most common. Main Clinical Findings and Diagnosis: 38 year male patient with a history of fourth recurrent anterior shoulder dislocation (RASD) reduced under anaesthesia was immobilized in sling for 6 weeks. After immobilization, active assisted flexion and abduction was restricted to 90° associated with pain and feeling of instability. Interventions: Integrative treatments of Ayurveda and Physiotherapy were given in three divided sessions, 7 days in each session for a total of 21 treatment days. Ayurveda treatments included Sthanika abhyanga (SA) and Shashtika shali pinda sweda (SSPS). Physiotherapy treatments included interferential therapy (IFT) and exercises. Outcome: Nourishing external treatments enhanced muscle strength and joint mobility. Conclusion: There was appreciable improvement in shoulder muscle strength, active range of motion (AROM) and no incidence of recurrence since past 2 years. The patient is able to carry out unhindered daily activities with full and free AROM.

Broń jako wyznacznik prestiżu, rekwizyt rytuału oraz świadectwo kontaktów w Barbaricum w młodszym okresie przedrzymskim i w okresie wpływów rzymskich

Broń jako wyznacznik prestiżu, rekwizyt rytuału oraz świadectwo kontaktów w Barbaricum w młodszym okresie przedrzymskim i w okresie wpływów rzymskich

Integrated Assembly and Flexible Movement of Microparts Using Multifunctional Bubble Microrobots.

Industrial robots have been widely used for manufacturing and assembly in factories. However, at the microscale, most assembly technologies can only pattern the micromodules together loosely and can hardly combine the micromodules to directly form an entity that cannot be easily dispersed. In this study, surface bubbles are made to function as microrobots on a chip. These microrobots can move, fix, lift, and drop microparts and integratively assemble them into a tightly connected entity. As an example, the assembly of a pair of microparts with dovetails is considered. A jacklike bubble robot is used to lift and drop a micropart with a tail, whereas a mobile microrobot is used to push the other micropart with the corresponding socket to the proper position so that the tail can be inserted into the socket. The assembled microparts with the tail-socket joint can move as an entity without separation. Similarly, different types of parts are integratively assembled to form various structures such as gears, snake-shaped chains, and vehicles, which are then driven by bubble microrobots to perform different forms of movement. This assembly technology is simple and efficient and is expected to play an important role in micro-operation, modular assembly, and tissue engineering.

Materials aspects associated with the addition of up to 20 mol% hydrogen into an existing natural gas distribution network

The introduction of hydrogen into the UK natural gas main has been reviewed in terms of how materials within the gas distribution network may be affected by contact with up to 80% Natural Gas (NG)/20 mol% hydrogen blend at up to 2 barg. A range of metallic, polymeric and elastomeric materials in the gas distribution network (GDN) were assessed via a combination of literature review and targeted practical test programmes.The work considered:• The effect of hydrogen on metallic materials identified in the network.• The effect of hydrogen on polymeric materials identified in the network.• The effect of hydrogen exposure on polyethylene pipeline joining and repair techniques (squeeze-off, and socket and saddle electrofusion joints)The experimental work involved soaking materials, under pressure conditions representative of the network, in 100% hydrogen, 20% hydrogen in methane, and 100% methane. For the metal samples, the test programme involved the assessment of hydrogen uptake on the tensile properties. For the polyethylene samples, the test programme looked at the assessment of possible hydrogen absorption/desorption and its effect on electrofusion jointing.The trials concluded that the majority of metallic materials showed no significant deterioration in mechanical (tensile) properties when stored in hydrogen environments compared to those stored in analogous methane or blended gas atmospheres up to 2 barg. Polymeric materials showed no deterioration to efficiency of squeeze-off or collar electrofusion in socket or shoulder orientations following soaking in hydrogen, methane or hydrogen blends.

JVS — Press review no. 2

Long-term obesity also affects the musculoskeletal system, mostly the joints, bones, muscles, tendons, and ligaments. Obesity damages the load-bearing tendons such as the patellar, Achilles, and plantar fascia. Obesity may also result in dislocations of the knee and causes multiple torn ligaments. Obesity may additionally be linked to chronic plantar heel pain. There are several different types of joints in the body. The synovial joints allow for motion, including flexion, extension, rotation, and abduction. These joints are divided into the ball and socket joints of the shoulders and hips, the hinge joints of the elbows and knees, the pivot joints of the atlas and axis, the condyloid joints of the wrists, the saddle joints of the thumbs, and the gliding joints of the fingers. The joints are affected by a variety of diseases, including osteoarthritis, rheumatoid arthritis, gout, and those of the vertebral column, often resulting in low back pain. Obesity is also linked to deteriorating bone density and muscle mass, resulting in a greater risk of falling and bone fractures. With obesity the adipocytes release bioactive peptides that affect connective tissues and damage their structure.

Behavior of traditional Chinese mortise-tenon joints: Experimental and numerical insight for coupled vertical and reversed cyclic horizontal loads

Mortise-tenon joints in traditional Chinese architecture are of major importance. Studying their performance under horizontal loads loads is paramount for China, where there are more than ten thousand historical pavilions and buildings –some of them 1000 years old-built with such a technology and where seismicity is high. To probe the impact of damage to mortise-tenon joints on the seismic performance of unidirectional straight-tenon wooden frames, this paper uses the so-called artificial damage simulation method. Under the condition of considering damage depth and degree of surface damage of the tenon, one intact wooden frame and 3 mortise-tenon wooden frames (having joints with different decay degrees of damage) are built in the laboratory using a 1:3.52 scale ratio. To obtain failure modes and hysteresis performance of the specimens, low-cycle reciprocating loading tests were conducted. This paper compares and analyzes the characteristics of edge point strain change of tenon and socket joints, the variation law of seismic performance such as hysteresis characteristics of the wood frame, the stiffness degradation and energy dissipation ability, and the accumulation of damage during repeated loading of the wood frame. Results show that, with an increase of the degree of decadent damage, the peak of the hysteresis curve of the wood frame decreases gradually, the tendency of the skeleton curve is flattened, the equivalent viscous damping coefficient decreases, and the seismic behavior of the wood frame drops. A sophisticated FE approach with contact-frictional interfaces at the mortise-tenon joints and with beams exhibiting a non-linear behavior is adopted to fit data obtained experimentally in the lab. A satisfactory agreement is found between numerical simulations and experimental results, with the comparison giving interesting insight into the expected behavior of such connections in case of an earthquake.

A novel temporary cranial fixation device for awake cranial surgery: Technical report of 14 cases.

Background:Awake craniotomy has become the gold standard in various cranial procedures. As part of the awake technique, three-point pin fixation of the patient’s head is important. One of the issues we encountered is the problem of matching the scalp infiltration site with the final pin position. To overcome this problem, we developed a flat plunger type fixator that adapts to the Mayfield holder.Methods:Our fixator has a 2.5 cm metallic shaft that articulates in a ball and socket joint to allow its concave surfaces to adapt to the patient’s scalp. After placing the patient in the desired position, the head is fixed with the three plungers, circles are drawn around each plunger, and they are then removed for the circles to be infiltrated with bupivacaine. Standard fixation pins are then placed in the Mayfield holder and aimed at the center of the circles.Results:So far, we have operated on 14 patients with this technique. No patient experienced pain during temporary fixation, and the drawn circles ensured that there were no mismatches between the local anesthetic and pin locations. The technique was particularly useful on hairy scalps, where infiltration sites were hidden. We also used only 22.5 mg bupivacaine at the pin sites, freeing a dose for the field block around the scalp incision.Conclusion:The temporary plunger type fixator provided a simple method to economize on local anesthetic use, check the patient’s head position before final fixation, and ensure that the Mayfield pins matched with the anesthetized area.

Experimental Study on the Seismic Performance of Socket Bridge Piers

In order to accelerate the construction of bridge substructure, a socket joint construction that does not require interfaces roughening between the precast columns and the reserved cavity of the precast foundation is raised in this paper. The seismic performance of such fabricated bridge piers was investigated by carrying quasistatic tests on socket circular pier specimens of different embedment depths with a compared cast‐in‐place pier specimen. The experimental results showed that the prefabricated piers with the embedment length larger than 1.0 times the column diameter, featuring smooth interfaces that was free of roughening, had a failure mode of bending damage as well as the cast‐in‐place component. As the embedment depth increases, the seismic performance indexes of the socket bridge pier, including bearing capacity, ductility, and energy dissipation capacity, are improved. The seismic performance indexes of a socket bridge pier specimen with an embedment depth of 1.5 times the column’s diameter in the test are better than the cast‐in‐place one.

Multidirectional 3D-printed functionally graded modular joint actuated by TCPFL muscles for soft robots

Highly deformable bodies are essential for numerous types of applications in all sorts of environments. Joint-like structures comprising a ball and socket joint have many degrees of freedom that allow mobility of many biomimetic structures. Recently, soft robots are favored over rigid structures for their highly compliant material, high-deformation properties at low forces, and ability to operate in difficult environments. However, it is still challenging to fabricate complex designs that satisfy application constraints due to the combined effects of material properties, actuation method, and structural geometry on the performance of the soft robot. Therefore, a combination of a rigid joint and a soft body can help achieve modular robots with fully functional body morphology. Yet, the fabrication of soft parts requires extensive molding for complex shapes, which comprises several processes and can be time-consuming. In addition, molded connections between extremely soft materials and hard materials can be critical failing points. In this paper, we present a functionally graded 3D-printed joint-like structure actuated by novel contractile actuators. Functionally graded materials (FGMs) via 3D printing allow for extensive material property enhancement and control which warrant tunable functionalities of the system. The 3D-printed structure is made of 3 rigid ball and socket joints connected in series and actuated by integrating twisted and coiled polymer fishing line (TCPFL) actuators, which are confined in the FGM accordion-shaped channels. The implementation of the untethered TCPFL actuation system can be highly beneficial for deployment in environments that require low vibrations and silent actuation. The fishing line TCP actuators produce an actuation strain up to 40% and bend the joint up to 40° in any direction. The TCPFL can be actuated individually or as a group to control the bending trajectory of the modular joint, which is beneficial when deployed in areas that contain small crevices. Obtaining complex modes of bending, the FGM multidirectional joint demonstrated a great potential to achieve different functionalities such as crawling, rolling, swimming, or underwater exploration.

Gyroscopic Optimization for Aerospace Applications

This paper describes a Gyroscope balancing device which is gravity operated. The device is mounted at the base of the gyroscopes which are installed in the aircrafts. The device is for vertical gyroscopes. When the aircraft turns or heads upwards or downwards an error is introduced in the gyroscopes, as the base of the gyroscopes get inclined. In order to reduce this error, the inventions has four rectangular compartments in which metallic balls are placed which slide to the other end when the planes inclines in a particular direction and activate a touch switch which magnetizes the magnet at the opposite end which pull a disc mounted on a ball socket joint placed at the center of the four compartments, and on this disc the gyroscope is mounted. As the disc is attracted by a magnet it inclines in that direction which is opposite to the inclination of the aircraft and therefore keeps the gyroscope straight.

Advances on the study of movable artificial vertebral body

At present, artificial vertebral implants have proven to be effective in the treatment of spinal tumors, infections, fractures and other diseases. However, the fusion artificial vertebral body can cause adjacent intervertebral joint degeneration and loss of original physiological curvature and activity. The movable artificial vertebral body can, to some extent, restore the normal physiological movement and reduce biomechanical changes of the spine, reducing the occurrence of complication. The design of movable artificial vertebral body is to equip movable device when the basis of reliable stability is obtained. According to its principle it can be divided into ball socket joint or elastic deformation. However the overall design of movable artificial vertebral body needs further improvement. Traditional mechanical processing methods are difficult to process complex prostheses and the agreement rate between traditional produced prostheses and lesions was low. While the emerging 3D printing technology can achieve individualized improvement of prosthesis, its slow rate and high cost need to be improved. The materials of movable artificial vertebral body includes metal, ceramics, biomaterials, high polymer materials and so on. Titanium alloy is the main material in metal materials, which is widely used, but its modulus of elasticity is still far from that of human bone and it lacks ideal bone fusion. Ceramic materials are rich in variety but fragile and poor in wear resistance. Biomaterials include autogenous bone, allogeneic bone, etc., with limited source and complicated operation. There are many kinds of polymer and biodegradable materials which obtain excellent and ideal properties. But their properties and applications need to be further studied. The movable artificial vertebral body still needs to be promoted and developed. The clinical experimental data is still insufficient, and long-term curative effect needs to be further observed and studied. This paper reviews the development, advantages, design, processing and materials of movable artificial vertebral bodies and provides useful reference for optimization design, processing and clinical application of movable artificial vertebral bodies.

On the Influence of the Shoulder Kinematic Chain on Joint Kinematics and Musculotendon Lengths During Wheelchair Propulsion Estimated From Multibody Kinematics Optimization.

Multibody kinematic optimization is frequently used to assess shoulder kinematics during manual wheelchair (MWC) propulsion, but multiple kinematics chains are available. It is hypothesized that these different kinematic chains affect marker tracking, shoulder kinematics, and resulting musculotendon (MT) lengths. In this study, shoulder kinematics and MT lengths obtained from four shoulder kinematic chains (open-loop thorax-clavicle-scapula-humerus (M1), closed-loop with contact ellipsoid (M2), scapula rhythm from regression equations (M3), and a single ball-and- socket joint between the thorax and the humerus (M4) were compared. Right-side shoulder kinematics from seven subjects were obtained with 34 reflective markers and a scapula locator using an optoelectronic motion capture system while propelling on a MWC simulator. Data were processed based on the four models. The results showed the impact of shoulder kinematic chains on all studied variables. Marker reconstruction errors were found to be similar between M1 and M2 and lower than for M3 and M4. Few degrees-of-freedom (DoF) were noticeably different between M1 and M2, but all shoulder DoFs were significantly affected between M1 and M4. As a consequence of differences in joint kinematics, MT lengths were affected by the kinematic chain definition. The contact ellipsoid (M2) was found as a good trade-off between marker tracking and penetration avoidance of the scapula. The regression-based model (M3) was less efficient due to limited humerus elevation during MWC propulsion, as well as the ball-and-socket model (M4) which appeared not suitable for upper limbs activities, including MWC propulsion.

Ultrasonic Evaluation of the Thermomechanical Characteristics of TiNi Blanks

In this work, features of the characteristics of alloys with the shape memory effect and hyperelasticity are considered. The principles of evaluation of the thermomechanical characteristics of the blank material before its immediate application are presented. In this work, the ultrasonic method for evaluation of the phase transformations in blanks of thermomechanical joint sockets is discussed.

Developmental Dysplasia of Hip: Perspectives in Genetic Screening.

Development dysplasia of the hip (DDH) is a complex developmental disorder despite being a relatively common condition mainly caused by incompatibility of the femoral head and the abnormal joint socket. Development dysplasia of the hip describes a wide spectrum of disorders ranging from minor acetabular dysplasia to irreducible dislocation of the hip. Modern medicine still suffers from lack of information about screening and precise genetic examination. Genome wide linkage and association studies have brought significant progress to DDH diagnosis. Association studies managed to identify many candidate (susceptible) genes, such as PAPPA2, COL2A1, HOXD9, GDF-5, and TGFB1, which play a considerable role in the pathogenesis of DDH. Early detection of DDH has a big chance to help in preventing further disability and improve the psychological health and quality of life in those children. This emphasizes the importance to establish a universal screening program along with the genetic counseling.