Joint Area Research Articles

Anatomical variants complicating the posterior approaches towards the elbow joint

IntroductionAnatomical variants observed during the posterior approach to the elbow joint require special attention due to their clinical relevance. We aim to present a compendious review of described variants potentially encountered during the posterior approach towards the elbow joint to the experts in the elbow surgery.MethodsA narrative review of surgical and anatomical textbooks, as well as search of scientific databases was carried out.ResultsVariability of the subcutaneous nerves is important during incision planning. Accessory muscles such as dorsoepitrochlearis, chondroepitrochlearis, epitrochleoanconeus, subanconeus or supernumerary flexor carpi ulnaris may confuse even the senior surgeon during the dissection and possibly complicate the fracture reduction. Some bony variants such as supratrochlear foramen may lead to fracture or possibly interfere with the osteosynthesis placement. Accessory bones are also present in the region of the elbow joint. Those situated intra-articular may present with symptoms.ConclusionMany variants can be encountered in the area of the elbow joint and their knowledge is essential to truly understand its anatomy. The presented review enables easier orientation in the current literature with the aim on the posterior approach towards the elbow joint.

Biomechanical research progress of common acetabular reconstruction techniques for Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip

To summarize the characteristics and biomechanical research progress of common acetabular reconstruction techniques in patients with Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip (DDH) undergoing total hip arthroplasty (THA), and provide references for selecting appropriate acetabular reconstruction techniques for clinical treatment of Crowe type Ⅱ and Ⅲ DDH. The domestic and foreign relevant literature on biomechanics of acetabular reconstruction with Crowe type Ⅱ and Ⅲ DDH was reviewed, and the research progress was summarized. At present, there are many acetabular reconstruction techniques in Crowe type Ⅱ and Ⅲ DDH patients undergoing THA, with their own characteristics due to structural and biomechanical differences. The acetabular roof reconstruction technique enables the acetabular cup prosthesis to obtain satisfactory initial stability, increases the acetabular bone reserve, and provides a bone mass basis for the possible secondary revision. The medial protrusio technique (MPT) reduces the stress in the weight-bearing area of the hip joint and the wear of the prosthesis, and increases the service life of the prosthesis. Small acetabulum cup technique enables shallow small acetabulum to match suitable acetabulum cup to obtain ideal cup coverage, but small acetabulum cup also increases the stress per unit area of acetabulum cup, which is not conducive to the long-term effectiveness. The rotation center up-shifting technique increases the initial stability of the cup. Currently, there is no detailed standard guidance for the selection of acetabular reconstruction in THA with Crowe type Ⅱ and Ⅲ DDH, and the appropriate acetabular reconstruction technique should be selected according to the different types of DDH.

The Association between COVID-19 Related Anxiety, Stress, Depression, Temporomandibular Disorders, and Headaches from Childhood to Adulthood: A Systematic Review

Objective: The coronavirus belongs to the family of Coronaviridae, which are not branched single-stranded RNA viruses. COVID-19 creates respiratory problems and infections ranging from mild to severe. The virus features mechanisms that serve to delay the cellular immune response. The host's response is responsible for the pathological process that leads to tissue destruction. Temporomandibular disorders are manifested by painful jaw musculature and jaw joint areas, clicks, or creaks when opening or closing the mouth. All these symptoms can be disabling and occur during chewing and when the patient yawns or even speaks. The pandemic situation has exacerbated anxieties and amplified the vulnerability of individuals. Therefore, from this mechanism, how the COVID-19 pandemic may have increased the incidence of temporomandibular disorders is perceived. The purpose of this review is to evaluate whether COVID-19-related anxiety has caused an increase in temporomandibular dysfunction symptoms in adults to children. Methods: PubMed, Web of Science, Lilacs, and Scopus were systematically searched, until 30 July 2022, to identify studies presenting: the connection between COVID-19 with temporomandibular disorders. Results: From 198 papers, 4 studies were included. Literature studies have shown that the state of uncertainty and anxiety has led to an increase in the incidence of this type of disorder, although not all studies agree. Seventy-three studies were identified after viewing all four search engines; at the end of the screening phase, only four were considered that met the PECO, the planned inclusion, and the exclusion criteria. All studies showed a statistically significant correlation between temporomandibular disorders and COVID-19 with a p < 0.05. Conclusions: All studies agreed that there is an association between COVID-19 and increased incidence of temporomandibular disorders.

Failure Analysis of Printed Circuit Board Solder Joint under Thermal Shock

Investigating the failure mechanism of solder joints under different temperature conditions is significant to ensure the service life of a printed circuit board (PCB). In this research, the stress and strain distribution of a PCB solder joint was evaluated by high- and low-temperature thermal shock tests. The cross-section of the solder joint after thermal shock testing was measured using a 3D stereoscopic microscope and SEM equipped with EDS. The microstructure of the lead-free solder joint and the phase of the intermetallic compound (IMC) layer were studied by XRD. The working state of the PCB solder joint under thermal shock was simulated and analyzed by the finite element method. The results show that thermal shock has a great effect on the reliability of solder joints. The location of the actual crack is consistent with the maximum stress–strain concentration area of the simulated solder joint. The brittle Cu6Sn5 and Cu3Sn phases at the interface accelerate the failure of solder joints. Limiting the growth of Cu6Sn5 and Cu3Sn phases can improve the reliability of solder joints to a certain extent.

Tool parameters to minimize temperature changes in bone drilling

Drilling is a common technique used in orthopedic surgery procedures but causes increases in temperature that can lead to cell damage and death. The extent of this depends largely on the magnitude of the increase in temperature. The commonly accepted limit to prevent osteonecrosis is less than 47°C for 60s. There is controversy when it comes to the optimal drilling parameters that limit temperature increases and cell death. In addition to this, less research has been done on the drilling effects in the osteochondral area of joints. Osteochondral tissue damage can interfere with the daily lives of patients and if severe enough will need to be treated. We hypothesize that increasing tool speed and drill bit size will increase temperature that could be above the osteonecrosis limit. Ex-vivo experiments were conducted on porcine shoulder joints that tested the thermal effects of different tool speeds and drill bit sizes. A thermal camera was used to record and measure real time temperature changes while drilling. Three drill bit sizes and five tool speeds were used. Statistical analyses includes Welch's ANOVA with Games-Howell Post Hoc analyses, multivariate linear regression, and surface response regression were used to explore the association of tool speeds and drill bit size on temperature. All the tool speed and drill bit size combinations lead to an increase in temperature that were under the commonly accepted limit. The highest temperature reached was 44°C with a tool speed of 1150 RPM and 3070 RPM and drill bit size 5.159mm. It was found that increasing the tool speed increased the temperature change and increasing the drill bit size increased the temperature change.

Cartilage Injury Repair by Human Umbilical Cord Wharton's Jelly/Hydrogel Combined with Chondrocyte.

Purpose: There is still a lack of effective treatments for cartilage damage. Cartilage tissue engineering could be a promising treatment method. Human umbilical cord Wharton's jelly (HUCWJ) and hydrogels have received wide attention as a scaffold for tissue engineering. They have not been widely used in clinical studies as their effectiveness and safety are still controversial. This study systematically compared the ability of these two biological tissue engineering materials to carry chondrocytes to repair cartilage injury in vivo. Methods: Chondrocytes were cocultured with HUCWJ or hydrogel for in vivo transplantation. The treatments comprised the HUCWJ+cell, hydrogel+cell, and blank groups. A rabbit model with articular cartilage defect in the knee joint area was established. The defective knee cartilage of different rabbit groups was treated for 3 and 6 months. The efficacy of the various treatments on articular cartilage injury was evaluated by immunohistochemistry and biochemical indices. Results: We found that the HUCWJ+cell and hydrogel+cell groups promoted cartilage repair compared with the blank group, which had no repair effect. The treatment efficacy of each group at 6 months was significantly better than that at 3 months. HUCWJ showed accelerated cartilage repair ability than the hydrogel. Conclusion: This study showed that HUCWJ is useful in cartilage tissue engineering to enhance the efficacy of chondrocyte-based cartilage repair, providing new insights for regenerative medicine. Impact statement Human umbilical cord Wharton's jelly (HUCWJ) and hydrogel are the suitable extracellular matrix for cartilage tissue engineering. This study assessed the capacity of HUCWJ- and hydrogel-loaded chondrocytes to repair cartilage injury in vivo. The data demonstrate that both HUCWJ and hydrogel effectively facilitated cartilage repair, and the repair effects of HUCWJ were significantly better compared with hydrogel, therefore providing a potential candidate for clinical practice of cartilage regeneration therapy.

Ayurvedic Management of Dushtavrana (Non-Healing Ulcer)– A Case Report

Treatment of non-healing ulcers (dushtaVrana) is a clinical challenge. Even though contemporary medicine can manage infected wounds through antibiotics, non-healing wounds are still a problem to be solved. Ayurveda contributes significantly in the management of dushtavrana through its holistic approach. This case report discusses a 52-year-old male patient who complained of a non-healing ulcer over the left big toe's metatarsophalangeal joint area for six months. With associate complains of pricking pain and itching in the nearby area of the ulcer. Cleaning of the ulcer was done with Nomura arka (Distillation preparation of cow urine) followed by Dhara (wash) with kwatha prepared out of lodhra(SymplocosracemosaRoxb), yashtimadhu (Glycyrrhizaglabra), manjishta (Rubiacordifolia).Sadhyovirechana (Purgation therapy) is performed with trivrutlehua and milk. Orally Aragwadhadikashaya, Sarivadhyasava, and Guggulupanchapalachurna were administered. After 15 days of treatment, there was considerable relief in the pain, and the wound started healing. One month of treatment led to the complete healing of the wound. Parisheka of lodra, yashtimadhu, and manjishtakwatha helps clean and heal the wound due to its vranahara, sandhaneeyaaction. Virechana with Trivrutlehya helps in the elimination of vitiated pitta, which allows for enhancing wound healing. Aragwadhadikashayam helps in dushtaVranashodhana and reduces the itching.Sarivadhyasavaisamapachaka, pittahara and pidakahara.GuggulupanchapalachurnacontainsGuggulu, Pippali, Triphala, etc. as its contents. Hence it contributes to the management of pain and healing of the ulcer.

Features of ultrasound diagnostic syndesmotic ankle injuries in middle and older children: prospective comparative study

BACKGROUND: Diagnostics and treatment of syndesmotic ankle injuries in children is one of the important problems in pediatrics. The generally accepted examination algorithms and standards developed for adult patients do not apply to children. The ligamentous apparatus in children is much more elastic, and the tibiofibular space is smaller, which significantly complicates the diagnostic search.&#x0D; OBJECTIVE: This study aimed to create a diagnostic algorithm for examining middle and older children with ankle joint injuries.&#x0D; MATERIALS AND METHODS: To create a diagnostic algorithm, whether the ultrasonographic stress test of external foot rotation in adult practice is relevant for patients with closed growth zones was investigated. Two open cohorts of middle and older children were formed. The first cohort included children aged 1114 years with a closed growth zone of the distal tibia, and the second cohort included children aged 1517 years with a closed growth zone. The inclusion criteria were the absence of injuries of the studied ankle joint and the correspondence of the body mass index to the age norm.&#x0D; RESULTS: The variability of the tibiofibular space during the stress test of external foot rotation in children with a closing growth zone averages 3.035 mm and in children with a closed growth zone was 2.319 mm. Data indicate a high degree of elasticity of the anterior tibialperoneal ligament in children in contrast to adults in whom this structure is more rigid. In children experiencing pain, active muscle resistance makes the test of internal rotation ineffective, and excessive elasticity of the structure in the area of a healthy joint does not give a correct comparative result for the operator.&#x0D; CONCLUSION: The use of a test with internal rotation for diagnosing damage to the distal tibiofibular syndesmosis in children with closing and closed growth zones is limited, and the operator must rely on other ultrasound signs of damage to this structure.

Effect of microstructure and stress ratio on fatigue crack propagation behavior of A7N01 aluminum alloy fiber laser-VPTIG hybrid butt welded

In this paper, the fatigue crack growth rates of A7N01 aluminum alloy welded joint in weld zone (WZ) and heat affected zone (HAZ) are compared under the stress ratio of 0.1. At the same time, the fatigue crack growth rate of WZ under different stress ratios is studied. The results show that the difference of microstructure leads to different fatigue crack growth rates in different areas of welded joints. The HAZ shows better fatigue crack growth resistance and slower fatigue crack growth rate. However, due to the burning loss of Zn element in the WZ, the precipitation of strengthening phase after solidification in the molten pool is less, and the fatigue crack propagation resistance is weak. After 60 days of natural aging, the number of precipitated phases in the WZ and HAZ increased, and the fatigue crack propagation resistance is improved compared with that in the welded condition. Compared with grain boundary strengthening, precipitation strengthening is more important. With the increase of stress ratio, the fatigue crack closure effect in WZ gradually weakens, and the fatigue crack propagation rate increases.

Effect of void formation according to resin content on composite joint area

The field of application of Glass Fiber Reinforced Polymer expands as well as the size of the component where composite material is applied. Due to the size limitation of the prepreg used, it is difficult to apply 1ply to large parts. Many studies have been reported on the bolt joint that assembles parts and parts for the joint area, butt and overlap design for joining dissimilar materials, and mechanical properties. Although the mechanical properties of the joint areas are important, studies on the microstructure are also needed. In this study, the microstructure was observed by controlling the type of subsidiary materials in the bagging process by applying prepregs of the same composition. It was found that the air and resin flow inside the prepreg acted differently depending on the type of subsidiary material. The flow of resin during curing was inferred from the influence of subsidiary materials and explained by connecting it with the microstructure. The behavior of the resin determined thickness, resin, and void contents of the composite. This flow affects voids in the joint area, causing differences in microstructure and mechanical properties. There was no significant difference in the tensile strength of the laminate specimens manufactured according to the process, but the minimum strength was found in the specimens containing many void contents. The joint specimen showed a decrease in strength as the void content increased. It was discussed that this reduced the adhesive force of the specimen due to the effect of the void generated in the joint area.

Buttering for FSW: Enhancing the fracture toughness of Al-Fe intermetallics through nanocrystallinity and suppressing their growth

The formation of intermetallic compounds (IMCs) is an inevitable phenomenon during friction stir welding (FSW) of dissimilar metals. Majority of approaches that have ever been used to control the IMC thickness during FSW have been process-based. In the present study, the objective was to develop a novel metallurgical approach to control the growth and microstructure of AlFe IMCs during FSW. To do so, the faying surface of a structural carbon steel (CS) was buttered with stainless steel (SS) prior to the FSW process. The joints were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to study the intermetallic compounds. Tensile specimens with holes in the joint area were prepared and tested. The fracture surfaces of the specimens were studied by SEM. The analyses showed that the buttering caused the tensile strength and the fracture elongation to increase by 60 % and 250 %, respectively. SEM and TEM results revealed that there were two mechanisms responsible for this improvement. First, the thinning of the IMC layer and second, the nano-crystallinity of the IMC. The underlying physical phenomenon in controlling the IMCs thickness by this approach is discussed, highlighting the mechanisms by which the mechanical properties are enhanced. The alloying elements Cr and Ni introduced by the buttering technique were found to play the major role in controlling the thickness and nano-crystallinity of the IMC layers in the FSW of Al to St. It was found that the harmful intermetallic compounds in FSW of dissimilar metals can be effectively controlled by the alloying elements imparted through buttering before FSW.

Skin irritation in children undergoing orthodontic facemask therapy

Orthodontic facemasks are extraoral orthodontic appliances that influence maxillary and mandibular development in children with skeletal Class III malocclusion. While a facemask is most effective in patients before the growth spurt, skin irritation is common during the treatment. Therefore, this retrospective study aimed to investigate the prevalence and pattern of such skin changes and identify their possible associated risk factors. We included 177 patients with skeletal Class III malocclusion who underwent facemask therapy. Patient age and sex, orthodontic parameters expressing the severity of malocclusion, the presence of complaints in the temporomandibular joint (TMJ) areas, and the level of patient cooperation were evaluated. Additionally, the severity and onset time of skin reactions were further analyzed. The results indicated that 43.5% of patients developed skin changes typical of irritant contact dermatitis. Skin irritation was significantly associated with the presence of TMJ complaints and female sex. Furthermore, skin irritation was more common in younger patients. Clinicians should pay special attention to the skin areas that come into contact with the appliance during each follow-up visit to detect potential problems. Moreover, patients and their parents should be given adequate information about the possibility, prevention, and management of skin problems during facemask therapy.

Karakteristik Sifat Mekanik Hasil Pengelasan Gesek Aluminium dengan Tembaga Menggunakan Variasi Kecepatan Putar dan Kekasaran Permukaan Kontak

Friction welding is a type of welding that is used for a variety of materials. Friction welding is a method of joining two materials by swiping them together until they reach some of the melting points of the materials to be joined, then applying constant pressure. Aluminum and copper are the materials to be joined in this study. Using rotational speed and contact surface roughness variations. The purpose of this research is to determine the mechanical properties of friction welding results between aluminum and copper. The speed settings are 1230, 1500, and 2500 rpm. Use sandpaper grades #100, #800, and #1500 to achieve different levels of surface roughness. According to the results of this study, the rotational speed with the highest tensile strength and hardness values is 1230 rpm, namely 59.6 MPa and 54.6 HVN (Al), 112.1 HVN (Al) (Cu). In terms of surface roughness variations, the surface roughness using grade #1500 sandpaper has the highest value, namely 54.18 HVN (Al), 112.1 HVN (Cu). And #100 sandpaper with a value of 52.48 Mpa. The results of the microstructure test in the weld joint area at a magnification of 1000x indicated that the friction welding of aluminum and copper was successful, as evidenced by the diffusion of aluminum and copper in this area.

The Comparison Of The Low-Level Laser Therapy And High Intensity Laser Therapy On Pain And Functional Ability In Knee Osteoarthritis

Introduction: Osteoarthritis (OA) of the knee causes disability due to pain and will affect the functional ability to walk. Low-Level Laser Therapy (LLLT) has been shown to reduce pain in knee OA, while High Intensity Laser Therapy (HILT) is able to reach deeper joint areas.&#x0D; Method: This study aimed to compare the effect differences between LLLT and HILT on pain and functional capacity in knee OA. Methods: This is a double-blind randomized controlled trial with 61 subjects randomized into LLLT (n=31) and HILT (n=30) groups. All the subjects were knee OA patient with Visual Analog Scale (VAS) ≥ 4. The laser therapy and exercise were given 3 times per week for 6 sessions. The pain scale evaluated using VAS and functional ability evaluated using 50-feet walk test.&#x0D; Result: After 6 sessions, both LLLT and HILT group showed reduced VAS score [∆VAS Score LLLT = 3 (2 – 4), HILT = 3 (2 – 5)] and increased walking speed (∆ walking speed for LLLT = 0.23 (0.02 – 1.24) m/s, HILT = 0.22 (0.08 – 0.7) m/s) which were statistically (p &lt; 0.001) and clinically significant. HILT group had faster walking speed and greater VAS reduction compared to LLLT group (p &lt; 0.001), but there was no significant difference in walking speed between two groups (p=0.655).&#x0D; Conclusion: HILT and LLLT combined with exercise were effective in reducing pain and increasing functional ability in knee OA after 6 sessions of intervention. Pain and functional ability improvement was faster and greater in HILT group than LLLT group.&#x0D;

Evaluation of Local Application of Glucosamine Sulfate and Chondroitin Sulfate on Temporomandibular Joint Response and Alleviation of Pain and Tension During the Functional Treatment of Skeletal Class II Patients: A Randomized Control Clinical Trial.

This study was conducted to assess the effects of applying a gel ofcombined glucosamine sulfate and chondroitin sulfate on the temporomandibular joint (TMJ) area in patients with skeletal Class II malocclusion treated by removable functionalappliances in terms of TMJ internal proportions, levels of pain, and tension. The study included 36 patients aged 10-13 years with skeletal Class II malocclusion due to retrusion of the mandible characterized by:4-8 degrees of the sagittal skeletal discrepancy (ANB) angle,4-7 mm of overjet,72-76 degrees of the sagittal mandibular positioning (SNB) angle, and a bone maturity stage locatedat pubertal growth spurt. Patients were distributed to the experimental group (Twin-Block appliance + Jointance®gel)or thecontrol group (conventional treatment with the Twin-Block appliance). An allocation ratio of 1:1 was employed. Pre- and post-treatment digital lateral cephalometric radiograms were taken, and the TMJ joint spaces were measured using the Viewbox software (dHAL Software, Kifissia, Greece). The pain and discomfort levels were evaluated using a questionnaire with a four-point Likert scale at three assessment times. The anterior and posterior glenoid and anterior condylar distances to the pterygoid vertical (PTV) reference planesignificantly decreased after treatment (p<.001), and the anterior joint space decreased significantly (p<.001). In contrast, the superior distance of the condyle to the Frankfort horizontal reference planeincreased significantly after treatment, and the same results were found for the posterior and superior joint spaces (p<.05). There were no significant differences between the two groups in the evaluatedlinear variables. No significant differences were found when comparing pain and tension levels between the two groups at each assessment time. A gradual decrease in pain and tension levels was observed between the three evaluation times in both groups. A combinationof glucosamine sulfate and chondroitin sulfate did not affect the temporomandibular joint spaces, pain, and tension levelsin patients with skeletal Class II malocclusions treated by removable functional appliances.

Experimental investigation of the quantified influence of gypsum plasterboard joints on the fire performance of cold-formed steel walls

The fire-induced width development of a joint and the corresponding impact on the fire performance of cold-formed steel (CFS) walls were not quantified in previous investigations. Six non-cavity-insulated mid-scale CFS walls lined with artificial board joints were tested under ISO 834 fire conditions. Specimens were sheathed with double layer gypsum plasterboard (GP) on both sides and contained three types of GP board joints (face layer joint, base layer joint and overlapped joint). Moreover, 5 mm and 30 mm initial joint widths were set for each type of board joint to quantitatively investigate the negative impact of joints on the fire performance of walls and identify the positions on the wall that are vulnerable to fire-induced structural failure. Based on pixel comparison, the curves of the time-joint width are given, which can provide supporting data for investigating the heat transfer numerical simulation of CFS walls with joints in fire. In addition, the conventional numerical heat transfer model of CFS walls assigns the thermal boundary to the GP board joint surface. However, during the initial 30 min of fire exposure, temperatures at both the face layer joints and overlapped joints were significantly lower than the fire-side temperatures of the walls. Hence, the temperature results at the board joint of conventional numerical heat-transfer simulation results tend to be too conservative. It is suggested that the numerical heat transfer model of CFS walls should consider the development of GP board joint width and the flow-thermal coupling effect in the joint area. In addition, for a typical CFS load-bearing wall lined with double layers of GP boards on both sides, although each wall stud has the same vertical load (load ratio 0.65), fire-induced structural failure can occur when the HF critical temperature reaches 453 °C. Therefore, the wall stud adjacent to the overlapped joints will be the first to display fire-induced structural failure. Subsequently, the studs near the face layer joints will fail, and the wall studs near the base layer joints will fail last.

Characterization of Dual-Layer Hybrid Biomatrix for Future Use in Cutaneous Wound Healing.

A skin wound without immediate treatment could delay wound healing and may lead to death after severe infection (sepsis). Any interruption or inappropriate normal wound healing, mainly in these wounds, commonly resulted in prolonged and excessive skin contraction. Contraction is a common mechanism in wound healing phases and contributes 40-80% of the original wound size post-healing. Even though it is essential to accelerate wound healing, it also simultaneously limits movement, mainly in the joint area. In the worst-case scenario, prolonged contraction could lead to disfigurement and loss of tissue function. This study aimed to fabricate and characterise the elastin-fortified gelatin/polyvinyl alcohol (PVA) film layered on top of a collagen sponge as a bilayer hybrid biomatrix. Briefly, the combination of halal-based gelatin (4% (w/v)) and PVA ((4% (w/v)) was used to fabricate composite film, followed by the integration of poultry elastin (0.25 mg/mL) and 0.1% (w/v) genipin crosslinking. Furthermore, further analysis was conducted on the composite bilayer biomatrix's physicochemical and mechanical strength. The bilayer biomatrix demonstrated a slow biodegradation rate (0.374967 ± 0.031 mg/h), adequate water absorption (1078.734 ± 42.33%), reasonable water vapour transmission rate (WVTR) (724.6467 ± 70.69 g/m2 h) and porous (102.5944 ± 28.21%). The bilayer biomatrix also exhibited an excellent crosslinking degree and was mechanically robust. Besides, the elastin releasing study presented an acceptable rate post-integration with hybrid biomatrix. Therefore, the ready-to-use bilayer biomatrix will benefit therapeutic effects as an alternative treatment for future diabetic skin wound management.

A rare disease: Familial hyperphosphatemic tumoral calcinosis

Abstract Introduction Tumoral calcinosis (TC) is a rare disease characterized by soft tissue calcification as a result of repetitive trauma and prolonged pressure in periarticular areas of large joints; such as hip, knee, shoulder and elbow. There are three different forms; sporadic, familial and secondary TC due to chronic renal diseases, vitamin D hypervitaminosis. Familial hyperphosphatemic TC, which will be presented in this case, causes by relative deficiency or resistance of FGF-23, which is the critical regulatory hormone in the phosphorus metabolism. Clinical Case A 38-year-old male patient was referred from the nephrology department for hyperphosphatemia. He underwent 14 operations mass lesions, which were painful, progressively enlarging, in the different regions. His first operation at the age of 11 for a lesion in the right knee. Pathologic diagnoses of surgical specimens were reported as tumoral calcinosis. The patient was followed up by different orthopedic clinics from the age of 11, and was operated as new masses appeared. He does not have any complaints other than the pain in the periods when the lesions appear. He has 4 siblings without any known diseases, and his parents were third degree consanguineous. In physical examination, blood pressure was 115/72 mmHg, pulse was 76/min, and temperature was 36.7°C. Her height was 183 cm, and weight was 82 kg, BMI: 24.5 kg/m2. In laboratory tests, serum calcium 10.1 mg/dl, serum phosphate 6,8 mg/dl, parathormone 25 pg/ml, 25-OH Vitamin D 19 ng/ml, creatinine 0.9 mg/dl, alkaline phosphatase 71 U/l, 24-h urinary calcium 129 mg/day and 24-h urinary phosphate 205 mg/day. Bone mineral density at the femoral neck was 1.258 g/cm2, Z score was -1.6, and BMD at the lumbar spine was 1.081 g/cm2, Z score was -0.9. In bone survey, we detected that mild right-facing rotoscoliosis in the thoracolumbar region, increased calcification of the costosternal cartilages, osteophytic tapering in the thoracic region, intracranial calcification in the parietal region, L3-L4 level syndesmophyte, irregularity and adjacent soft tissue calcification at the distal phalanx level of the first toe of the right and left foot (Fig 1). We recommended the patient to avoid trauma and a low phosphorus diet. Maintenance dose vitamin D replacement and phosphorus-binding treatment (calcium-asetate 700 mg 3×2) with meals were started. When phosphate reduction could not be achieved, sevalemer 800 mg 3×3 was added with gradually increasing, phosphorus level dropped to 5.2 mg/dl. Genetic analysis revealed GALNT3 homozygous mutation. Genetic counseling and eye examination were recommended. Conclusion TC should also be considered in patients with a history of multiple surgery due to soft tissue masses, especially in the presence of hyperphosphatemia. In our case, a mutation was detected at a rather late age, and phosphorus-lowering therapy was started at the age of 38 years and genetic counseling should be offered to these patients at an early age.

Seismic performance test research on a new type of replaceable energy-consuming joint column

This study proposed a new type of fully-precast reinforced concrete column-column joint, a replaceable energy-consuming joint (RECJ), which was composed of tenons and replaceable energy-dissipating connecting plates. The joint's seismic behavior and failure mechanism were investigated using quasi-static tests on two RECJ-connecting precast columns, one cast-in situ column, and one repaired RECJ-connecting precast column. The results showed that the damage and destruction of RECJ-connecting specimens were mainly concentrated on the connecting steel plates, while the other parts were basically elastic, showing a compression-bending failure mode. The hysteresis curves of RECJ-connecting specimens were fully shuttle-shaped. Meanwhile, energy dissipation, ductility, and stiffness degradation performance of these specimens were significantly better than those of the monolithic concrete comparison column. At the same time, the specimen with a longer tenon exhibited better overall seismic performance than that with a shorter tenon, while having the same initial stiffness and bearing capacity as the cast-in situ column. The seismic performance of the repaired long-tenon RECJ-connecting specimen with connecting plates replaced was not significantly decreased compared with original specimen, which demonstrated that RECJ had fine repairability. The relevant parameters were optimized through finite element simulation (FEM). Finally, based on test results, the shear capacity equation of RECJ was deduced according to the force equilibrium of an isolated body in the joint area and the accuracy of the equation verified.

Seam Properties of Overlap Welding Strategies from Copper to Aluminum Using Green Laser Radiation for Battery Tab Connections in Electric Vehicles.

Laser beam welding of metals has progressed dramatically over the last years mainly arising from joining applications in the field of electromobility. Allowing the flexible, automated manufacturing of mechanically, electrically, and thermally stressed components, the process is more frequently applied for joining highly reflective materials, for example for battery tab and busbar connections. The local, non-contact energy input favors this welding technology; however, joining of copper and aluminum sheets still poses a challenge due to the physical properties of the joining partners and intermetallic phases from dissimilar metal interaction, which reduce seam performance. The use of green laser radiation compared to infrared laser radiation offers the advantage of a significantly increased absorptivity for copper materials. A changed incoupling behavior is observed, and a lower deep penetration threshold has been already proven for 515 nm wavelength. When copper and aluminum are welded with the former as top sheet, this welding mode is essential to overcome limited aspect ratios from heat conduction welding. However, the opportunities of applying these beam sources in combination with spatial power modulation to influence the interconnection area of copper-aluminum joints have not yet been studied. The aim of this work is therefore to investigate the seam properties and process stability of different overlap welding strategies using green laser radiation for dissimilar metal welding. A microstructural analysis of the different fusion zones and mechanical strength of the joints are presented. In addition, the experimental parameter sets were analyzed regarding their application in battery module busbars by examining the electrical resistance and temperature distribution after welding. A parameter window was identified for all investigated welding strategies, with the stitched seam achieving the most stable results.