Joint Stiffness Research Articles

Study on the Mechanical Properties and Design Method of Frame-Unit Bamboo Culm Members Based on Semi-Rigid Joints

The frame-unit bamboo culm structure system offers a novel approach to bamboo structure, combining advantages like reduced construction times and simplified joint designs. Despite its benefits, there is limited research on its mechanical properties and computational methodologies. This study conducted bending performance tests on simply supported frame-unit bamboo culm structures, revealing that the bending stiffness of the structure increases with the number of bolts in the edge joints, though with diminishing efficiency. Based on the experimental observations, a calculation model for this type of structure was established, proposing formulas to describe the stiffness relationships between the corner joints, edge joint, and the overall structure. Numerical simulations calculated the stiffness of the edge joint as a function of the number and placement of bolts, indicating that positioning bolts closer to the outer side enhances edge joint stiffness. By inputting the various rotational stiffness values of corner joints into the simulations and stiffness formulas, consistent total stiffness values were obtained, validating the proposed stiffness relationship formulas. The average stiffness values of the corner joints were derived from these formulas and experimental data, and the rotational stiffness of other types of corner points can also be obtained using this method. Furthermore, a finite element computational method tailored for this structural system was introduced, converting the actual structure into a beam element model for calculation. The equivalent joint forces can be distributed to various components of the actual structure, resulting in the internal force distribution of bamboo culms and bolts in the actual structure, thus achieving the design of the components. The calculated displacement values obtained from this method are close to the displacement values in the experiment, proving the feasibility of this method.

April 2024 Medical Image of the Month: Wind Instruments Player Exhibiting Exceptional Pulmonary Function

No abstract available. Manuscript truncated after 150 words. A 64-year-old man was referred to our pulmonary clinic for evaluation of his pulmonary status. He had a 7-year history of rheumatoid arthritis and was treated initially with steroids and subsequently maintained on methotrexate and monthly adalimumab injections monthly. The patient reported that his rheumatoid arthritis symptoms were controlled. He experienced no joint pain or morning stiffness at the time of evaluation. From a pulmonary perspective, he denied respiratory symptoms such as exertional shortness of breath, cough, wheezing, or chest tightness. He reported no limitations in physical activities. The patient has an occupational history of 45-years as a welder, with exposure to dust, metal fumes, benzene, and sulfur gas. The patient also has a 15 pack-year smoking history but quit 35 years ago. A high-resolution chest CT (Figure 1) ordered by his rheumatologist showed normal lung parenchyma. The first pulmonary function test (PFT), conducted on the initial pulmonary clinic visit …

Indications of Arthroscopy in the Treatment of Patellar Instability in Children.

Purpose Understanding the relevant risk factors for patellar instability and the clinical and radiographic testsnecessary to determine optimal treatment. This case series intends to evaluate arthroscopic indications in the treatment of patellar instability in children. Methods From 2013 to 2021, 33 patients (seven to 16 years of age) with 35 knees sustaining first-time dislocation with loose bodies, recurrent dislocation or subluxation, and habitual dislocation were arthroscopically operated on according to the flow chart. Periods of follow-up were two to 10 years (avg. 5.5 years). Follow-up assessment included the recurrence, complications (joint stiffness and excessive reduction), and the final function outcomes by using the Kujala score. Results Among 35 knees, there were two (5.7%) first dislocations, 30 (85.7%) recurrent dislocations, and three (8.6%) habitual dislocations, lateral release 27/35 (77.1%), medial reefing 23/35 (65.7%), reconstruction of the medial patellofemoral ligament(MPFL) 12/35 (34.3%). The major complication was a knee of extensive stiffness after medial reefing and lateral release. Recurrence was in 4/35 (11.4%) of knees, not correlated to lateral release (p=0.21), medial reefing, or reconstruction of MPFL (p=0.07); in about 23 knees of medial reefing, recurrence was significantly correlated to number of knots (p=0.045). The final functional results according to Kujala were 88-100 (avg. 95.5). Conclusions This study showed the role of arthroscopy in both medial reefing and reconstruction of MPFL in children by low recurrence rate and high Kujala score at final follow-up. There was no significant correlation between recurrence and the procedures as arthroscopic indications counted on the flow chart.

Arthroscopic Confirmation of Femoral Button Deployment During Posterior Cruciate Ligament Reconstruction

Posterior cruciate ligament (PCL) ruptures are uncommonly seen in knee ligament injuries. Cconservative treatment is often suitable for isolated tears with mild-to-moderate posterior knee laxity (grades I or II). However, surgical intervention is indicated for symptomatic grade III or multiligament knee injuries. PCL reconstruction has experienced continuous development due to the progress made in arthroscopic techniques and instruments. Abnormal positioning and tensioning of the femoral button result in multiple complications such as residual laxity, loss of quadriceps muscle strength, and joint stiffness. In this Technical Note, we describe direct arthroscopic visualization of the femoral button deployment in PCL reconstruction technique, and we discuss its importance to prevent complications related to button malposition.

Food related symptom aggravation in joint diseases: Observations from a secondary care Ayurveda arthritis center

Background: Food is generally being thought to have a connection with joint diseases. Ayurvedic literature has references to supports this, however, any conclusive research to support this idea is not yet available in the published literature. This study aim at observing any real association of food- and joint-related symptom intensity in people suffering with joint diseases. Materials and Methods: This is a cross-sectional, observational study where the respondents suffering with joint diseases, visiting a secondary care Ayurveda arthritis center, were asked to self-report if they identified any dietary association with the change in intensity of their joint-related symptoms. Results: Fifty-four patients (6.1% of 885 screened) have self-reported the association of 68 food items with increase in joint pain, swelling, and stiffness. 35 of 54 respondents (64.81%) had the Ayurveda diagnosis of Amavata (~rheumatoid arthritis). Highest joint symptom-related sensitivity was reported with food and drink items like curd 41 (75.9%), cold water 42 (77.8%), cold drink 38 (70.4%), ice-cream 35 (64.8), rice 33 (61.1%), and lemon 27 (50%). Conclusion: Food is found to have a definitive association with joint-related symptoms in a sub-population suffering with joint diseases. The study suggests that enquiry about food and its association with joint symptoms should be the part of routine enquiry in Ayurvedic rheumatology. Furthermore, such patients who are found to have a food-related symptom aggravation are needed to be treated differentially considering the food and disease association in mind.

Experimental investigation of aluminium alloy gusset joints’ dynamic response to lateral impact loads: Evaluating the influence of gusset plate bending stiffness

The traditional aluminium alloy gusset plate (AAG) joint is commonly regarded as a representative semi-rigid joint characterized by limited stiffness. This deficiency in stiffness significantly hampers its capacity for load transmission and resistance against progressive collapse in spatial grid structures. Notably, the dynamic response characteristics of semi-rigid joints, especially when subjected to short-term, highly intense loads such as impacts and explosions, deviate substantially from those of rigid joints. This research examines the dynamic failure behavior of six distinct traditional AAG joints with varying degrees of stiffness when subjected to impact loads. The first group comprises three specimens where the variance in AAG joint stiffness is achieved by altering the gusset plate’s diameter. The second group comprises three specimens aiming to manipulate the AAG joint’s stiffness by modifying the gusset plate’s thickness. The study yielded comprehensive data, including stress profiles, displacement patterns, acceleration time history curves, and failure modes of AAG joints. The experimental findings revealed that both groups of AAG joints under lateral impact loads exhibited brittle failure. The predominant failure modes included the rupture of the H-shaped aluminium alloy beam, distortional buckling of the beam, and warping of the thinner gusset plate. It is evident from the stress, displacement, and acceleration time history curves that the AAG joint adheres to the characteristics of a typical semi-rigid joint, and the diameter and thickness of the gusset plate exert significant influence on the AAG joint’s dynamic response. Subsequently, the six test conditions were simulated using ANSYS/LS-DYNA software. This simulation considered the stress distribution, impact force time history curves, and strain energy time history curves of AAG joints. It facilitated a detailed discussion of the failure mechanism underlying AAG joints when subjected to lateral impact loads.

Peri-articular Dextrose Prolotherapy: Investigating the Effect of Injection Site on Knee Osteoarthritis Pain: A Double-Blind, Randomized, Clinical Trial.

Osteoarthritis (OA) is a chronic health condition that affects millions of people worldwide. It not only causes pain and physical limitations but also impacts mental health, sleep, work participation, and even mortality. Peri-articular dextrose prolotherapy has been shown to reduce knee osteoarthritis pain; however, the effect of injection sites on its effectiveness is not clear. This study aimed to investigate the effect of injection points on pain intensity, joint stiffness, and physical activity in patients with knee osteoarthritis who underwent peri-articular dextrose prolotherapy. This double-blind clinical trial involved 26 patients with grade 2 and 3 bilateral knee osteoarthritis. Three times every one week, dextrose and lidocaine were injected as interventions. Injection sites were positioned within acupuncture points on one knee, but were relocated by 1.5 centimeters to the medial side of the same acupuncture points on the other knee. Pain intensity, joint stiffness, and physical activity were evaluated using the Visual Analog Pain Scale (VAS) and the Persian version of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) before the intervention and at each follow-up visit at 1 and 2 months post-injection. Pain intensity score, joint stiffness, physical performance, and WOMAC were significantly decreased one and two months after the intervention in both groups (P = 0.0001). The improvement in the patients of both groups was similar, and the two study groups did not have a statistically significant difference in terms of study outcomes (P = 0.37). Prolotherapy with dextrose is an effective treatment for knee osteoarthritis.

Prognostic modeling in early rheumatoid arthritis: reconsidering the predictive role of disease activity scores.

In this prospective cohort study, we provide several prognostic models to predict functional status as measured by the modified Health Assessment Questionnaire (mHAQ). The early adoption of the treat-to-target strategy in this cohort offered a unique opportunity to identify predictive factors using longitudinal data across 20years. A cohort of 397 patients with early RA was used to develop statistical models to predict mHAQ score measured at baseline, 12months, and 18months post diagnosis, as well as serially measured mHAQ. Demographic data, clinical measures, autoantibodies, medication use, comorbid conditions, and baseline mHAQ were considered as predictors. The discriminative performance of models was comparable to previous work, with an area under the receiver operator curve ranging from 0.64 to 0.88. The most consistent predictive variable was baseline mHAQ. Patient-reported outcomes including early morning stiffness, tender joint count (TJC), fatigue, pain, and patient global assessment were positively predictive of a higher mHAQ at baseline and longitudinally, as was the physician global assessment and C-reactive protein. When considering future function, a higher TJC predicted persistent disability while a higher swollen joint count predicted functional improvements with treatment. In our study of mHAQ prediction in RA patients receiving treat-to-target therapy, patient-reported outcomes were most consistently predictive of function. Patients with high disease activity due predominantly to tenderness scores rather than swelling may benefit from less aggressive treatment escalation and an emphasis on non-pharmacological therapies, allowing for a more personalized approach to treatment. Key Points •Long-term use of the treat-to-target strategy in this patient cohort offers a unique opportunity to develop prognostic models for functional outcomes using extensive longitudinal data. •Patient reported outcomes were more consistent predictors of function than traditional prognostic markers. •Tender joint count and swollen joint count had discordant relationships with future function, adding weight to the possibility that disease activity may better guide treatment when the components are considered separately.

Inverse dynamics analysis of a 6-RR-RP-RR parallel manipulator with offset universal joints

AbstractThis paper presents an algorithm for solving the inverse dynamics of a parallel manipulator (PM) with offset universal joints (RR–joints) via the Newton–Euler method. The PM with RR–joints increase the joint stiffness and enlarge the workspace but introduces additional joint parameters and constraint torques, rendering the dynamics more complex. Unlike existing studies on PMs with RR–joints, which emphasize the kinematics and joint performance, this paper studies the dynamical model. First, an iterative algorithm is established through a rigid body velocity transformation, which calculates the input parameters of the link velocity and acceleration. A linear system of equations in matrix form is then established for the entire PM through the Newton–Euler method. By using the generalized minimal residual method (GMRES) to solve the equation system, all the forces and torques on the joints can be obtained, from which the required actuation force can be derived. This method is validated through numerical simulations using the automatic dynamic analysis of multibody systems software. The proposed method is suitable for establishing the dynamic model of complex PMs with redundant or hybrid structures.

A Rare Case of Multicentric Reticulohistiocytosis in An Elderly Male Patient

Multicentric reticulohistiocytosis (MRH) is a rare systemic proliferative granulomatous disease of non-Langerhans cells. The aim of this study is to report a case of multicentric reticulohistiocytosis that is easily misdiagnosed in clinical practice. A 74-year-old man sought the Rheumatology office in December 2022 with a main complaint of arthralgia for six months, associated with morning stiffness, joint swelling, and upper and lower limb weakness. On physical examination, papules on the dorsal surface of the proximal interphalangeal joints, base of the nose, and lateral surface of the right hallux were observed. Hyperemia was also identified on the back, and edema of the proximal and distal interphalangeal joints, wrists and knees. Laboratory tests revealed ESR and ANA within normal limits. Tests were negative for Anti-Sm, Anti-RO, rheumatoid factor, Anti-CCP, HIV, and HCV. Chest CT-scan showed right axillary lymph node enlargement, measuring 2.7 cm, atheromatous aorta, and streaks with scattered atelectasis in the lower lobe, without other changes. On total abdominal ultrasound, prostate enlargement was detected. Immunohistochemistry of skin biopsy identified atypical acinar proliferation. Histopathology skin biopsy stained with hematoxylin-eosin (January 2023) showed a dense histiocytic infiltrate. Detail of the histiocytic component displayed “ground glass” eosinophilic cytoplasm. Immunohistochemistry was negative for S100 and CD34 and positive for CD68. Final diagnosis was MRH. The patient underwent treatment with drugs. In conclusion, clinical manifestations, including skin and joint changes, with signs and symptoms of rheumatic disorders (e.g. dermatomyositis and rheumatoid arthritis) similar to those of MRH are expected in rheumatology practice. However, knowledge about disease progression in MRH is limited. Therefore, this case report is described due to its rarity Keywords: Non-Langerhans-Cell Histiocytosis, Pathology, Muticentric Reticulohistiocytosis, Rheumatological Diseases,

Physiotherapeutic Intervention Techniques for Knee Osteoarthritis: A Systematic Review.

Globally, knee osteoarthritis (KOA) is the leading cause of disability. The most prevalent complaints associated with KOA are knee pain, joint stiffness, and weakness in the muscles of the lower limbs. These symptoms impede movement and result in functional limitations. As a result, people with KOA have a lower quality of life. For all patient groups with knee OA, an effective rehabilitation program focuses on improving knee range of motion, isometric quadriceps strength, and productivity level while reducing discomfort. The American College of Rheumatology (ACR) categorization criteria for KOA, research on KOA physiotherapy, and reviews covering various physical therapy interventions, including exercise, physical modalities, and patient education, were used to narrow down the pool of 180 systematic reviews to 15 articles. Google Scholar, PubMed, the Cochrane Library, and EMBASE were the databases that were used. The following keyword combinations were included in our search: KOA and physiotherapy or interventions or exercises, strengthening and stretching, concentric and eccentric training. Through our analysis, we identified a few methods that, in addition to standard therapy, could be used in clinical settings for people with osteoarthritis in the knee. It has been shown that Mulligan, Pilates, Kinesiotaping, Aquatic Therapy, and other current therapies are effective. The study employed a broad range of results. This review concludes that rather than relying solely on conventional therapy, it is preferable to combine a number of the most current physiotherapy techniques with it.

Multi-objective optimization of assembly free-form cable-stiffened reticulated shell considering the influence of initial states

In this study, we propose a geometric model of free-form grid structures based on the sliding translation method. Furthermore, an end-flattened inserted-plate joint could be applied to a quadrilateral free-form grid structure. The height of the control point was considered as the optimization variable, while the strain energy, geometric integrated index, and ultimate bearing capacity were considered as the optimization objectives. The results demonstrated the influence of the initial prestress and joint stiffness using multi-objective optimization. Based on the effects of the initial prestress, joint stiffness, and initial geometric imperfections, we propose a multi-objective optimization method for the assembly of a free-form cable-stiffened reticulated shell. The feasibility of the optimization method was verified using examples. Compared with the results of the shape optimization, structures having superior mechanical properties and mesh quality were obtained via the combined method for optimizing the shape and initial prestress, which verified the necessity and effectiveness of the combined optimization method. The mechanical properties of the optimized structures were improved by increasing the joint stiffness; in particular, the ultimate bearing capacity was improved. On using the multi-objective optimization method while considering the initial geometric imperfections, the properties of the structure were improved effectively, and the mechanical properties can be guaranteed even after geometric imperfections are applied.

Brepocitinib, a potent and selective TYK2/JAK1 inhibitor: scientific and clinical rationale for dermatomyositis.

Dermatomyositis (DM) is a rare and debilitating, systemic, autoimmune disease. While heterogenous in presentation and severity, DM is primarily characterised by a spectrum of skin and muscle disease, which may include proximal muscle weakness and recalcitrant cutaneous eruptions. DM may also be associated with joint pain and stiffness, inflammatory arthritis, dysphagia, fatigue, and calcinosis. The current standard of care for DM includes glucocorticoids, immunosuppressants, and intravenous immunoglobulin (IVIg). Unfortunately, these medications are not uniformly effective and can lead to adverse events, particularly with chronic use, necessitating discontinuation of therapy. Therefore, a substantial unmet need exists for more tailored and efficacious therapies that target DM pathogenesis. Brepocitinib is an oral, once-daily, novel, and specific TYK2/JAK1 inhibitor. Brepocitinib's potent inhibition of TYK2 and JAK1 reduces the signalling of pro-inflammatory cytokines, including IFN-α/β, IL-12, IL-23, and IFNγ, that have been implicated in the pathogenesis of DM. Other JAK inhibitors have been used off-label in both case series and open-label clinical trials in patients with DM; and brepocitinib has demonstrated efficacy in phase 2 clinical trials of several other autoimmune diseases, including plaque psoriasis, psoriatic arthritis, Crohn's disease, hidradenitis suppurativa, and ulcerative colitis. Therefore, there is a strong scientific and clinical rationale for the utility and potential effectiveness of brepocitinib in the treatment of DM patients. Currently, the safety, tolerability, and efficacy of brepocitinib is being evaluated in the largest (n=225) double-blind placebo-controlled phase 3 trial in DM patients to date (VALOR - NCT0543726).

Design and Analysis of a Novel Variable Stiffness Joint Based on Leaf Springs

In response to challenges like the complexity and limited scalability of existing variable stiffness joints, a novel variable stiffness joint, based on leaf spring elements, is introduced in this paper. The joint stiffness can be adjusted in real time by changing the effective length of the leaf spring via the use of an Archimedean spiral groove. The stiffness adjustment range and load capacity of the joint can be defined by manually configuring the number of springs involved during offline joint operations. A stiffness model for the joint is established based on the cantilever beam theory of material mechanics. The coupled effects of the design parameters of the variable stiffness mechanism on joint stiffness, elastic torque, and stiffness adjustment resistance torque are analyzed. A dynamic model for the joint is developed, while a PID controller is designed for simulation purposes. The motion characteristics of the joint are analyzed, confirming that this approach has certain advantages in terms of stiffness adjustment speed and accuracy.

Pulsed shortwave electromagnetic field therapy increases quality of life in canines with symptoms of osteoarthritics.

Joint stiffness, lameness and reduced activity levels are common inflammatory responses observed in canines and have significant impact on quality of life (QOL). The symptoms are often ascribed to osteoarthritis (OA), for which the standard treatment is systemic anti-inflammatories, but pharmacologic intervention can have significant short-term and long-term side effects. Test the efficacy of a Food and Drug Administration (FDA)-cleared pulsed shortwave therapy (PSWT) device as a means to modulate vagus nerve activity and initiate a systemic anti-inflammatory response to determine its ability to improve functionality and the QOL of canines with inflammatory symptoms commonly associated with OA. A randomized, double-blinded, placebo-controlled 14-day study of 60 dogs with a presumptive prior diagnosis of OA in at least one limb joint. Two outcomes assessing changes in the dog's QOL and functionality were measured: subjectively determined changes in eight behaviours associated with discomfort and objectively determined changes in passive range of motion (PROM). The device was secured near the cervico-thoracic region of the dog's spine. PROM measures were taken at baseline and at the end of study. Behavioural measures were taken daily. Forty-nine animals completed the study. No negative side effects were reported. Average subjective discomfort scores for the treatment group (N=26) were reduced from 3.74 to 2.10 (44%), compared to no improvement in the placebo group (N=23) over the study period (p=0.0001). Average PROM scores increased by 5.51 (4.59-6.23) degrees relative to the placebo group (p<0.01). Ninety-six per cent of the treatment group showed either increased PROM or improved behavioural changes or both, compared to 4% for the placebo group (p<0.01). Most changes occurred within the first 8 days of treatment. PSWT applied at the level of the cervico-thoracic spine to target the vagus nerve may have the potential to improve QOL in dogs manifesting behaviours commonly associated with OA.

Optimization of stiffness performance of six-axis industrial robots based on posture stiffness evaluation index

Aiming at the problem that the stiffness performance of industrial robots depends on the posture, a method to improve the stiffness performance by optimizing the robot posture is proposed based on the robot posture stiffness evaluation index. The robot joint stiffness identification model is established by using the principle of virtual work and Jacobi matrix, and the stiffness values of six joints are obtained by least-squares. On the basis of revealing the mapping relationship between robot joints and end, the robot end flexibility ellipsoid is obtained, and the volume of the end flexibility ellipsoid is utilized as the global stiffness coefficient of the robot, so as to obtain the robot posture stiffness evaluation index. According to the posture stiffness evaluation index, the robot posture optimization model is established, and the optimized posture is obtained by using genetic algorithm. Taking the QJR6-1 robot as the experimental object, under the maximum load, the deformation of the robot end center is reduced from 0.6238 to 0.3984 mm, which is 36.13%, and the deformation of the end is greatly reduced compared with that before the optimization, which indicates that the robot’s stiffness is improved after the posture optimization, and it verifies the feasibility of the optimization model, and provides a reference to improve the stiffness performance of industrial robots further.

Cross-leg flaps: A nonmicrosurgical alternative treatment method in complex lower extremity trauma reconstruction.

This study aimed to present our experiences with cross-leg flap surgery, which demonstrates successful outcomes in lower limb soft tissue defects without the necessity of microsurgical intervention. The retrospective study included 26 patients (18 males, 8 females; mean age: 35.6±12.2 years; range, 18 to 65 years) between January 2015 and September 2019. A fasciocutaneous cross-leg flap was applied to the recipient extremity, and the extremities were immobilized by a tubular external fixator. Flap divisions were performed on the 21st postoperative day. At least two years of clinical outcomes were presented. Twenty-five flaps survived and recovered completely without any complication at the donor site, flaps, or the recipient area. In one diabetic patient, partial flap loss was encountered, which granulated with secondary healing. All patients demonstrated stable wound coverage, with none demanding additional soft tissue surgeries. All patients resumed normal ambulation and physical activity without any residual joint stiffness. Cross-leg flap method is an effective and respectable option for extremity salvage as a good alternative to free flaps for the management of traumatic complex lower limb defects. This method is simple, provides abundant blood supply to the wound, and does not require microsurgical experience or a good working recipient artery.

The Effectiveness of Rheumatic Gymnastics on Patella Joint Flexibility in Elderly with Rheumatoid Arthritis at the Elderly Integrated Service Post (Posyandu Lansia) in Mipiran Village, Purbalingga

Background: Based on data from the 2018 Riskesdas, 7.30% of the Indonesian population is estimated to suffer from rheumatoid arthritis. Rheumatoid arthritis (RA) is a chronic disease that causes joint pain, swelling, stiffness, and limited joint movement. As the most common autoimmune rheumatic disease, rheumatoid arthritis is a chronic inflammatory condition that permanently damages the joints, where the body's immune system, which generally protects the body from infections and diseases, attacks joint tissues for unknown reasons. Method: The research design used in this study was the Pre-Experimental one-group pre-test post-test method. The sample consisted of 31 individuals selected using a total sampling technique. The research instruments used were rheumatic gymnastics SOP and the Long-arm universal goniometer (UG) for measuring patella joint flexibility. Data were analyzed using the Wilcoxon statistical test. Results: There was an increase in the average value of right and left patella joint flexibility before and after the application of rheumatic gymnastics. The obtained P value was 0.005 for the right patella and 0.001 for the left patella. Both statistical analyses discovered that P-value was less than 0.05. Conclusion: Rheumatic gymnastics significantly affects patella joint flexibility in elderly patients with rheumatoid arthritis at the elderly integrated service post (Posyandu Lansia) in Mipiran Village, Purbalingga.

Analysis of the Effect of Rehabilitation Nursing Intervention on Functional Recovery in Patients with Rheumatoid Arthritis

Objective: To explore and analyze the effect of rehabilitation nursing intervention on functional recovery in patients with rheumatoid arthritis. Methods: From May 2020 to May 2023, 150 patients with rheumatoid arthritis who received integrated treatment of Tibetan and Western medicine in the rheumatology department were selected as the research subjects. They were divided into the rehabilitation group and the reference group according to the double-blind mechanism, with 75 cases in each group. The rehabilitation group received rehabilitation nursing intervention and the reference group received basic nursing. The standard of living, joint function recovery, and nursing satisfaction were compared between the two groups. Results: Before the intervention, there was no statistically significant difference (P &gt; 0.05) in living standards such as physiology, mental outlook, emotional performance, and social culture between the groups. After the intervention, the standard of living such as culture, of the rehabilitation group was significantly better than that of the reference group (P &lt; 0.05). Before the intervention, there was no statistically significant difference (P &gt; 0.05) in the recovery of joint functions such as the number of joint tenderness, grip strength of both hands, duration of morning stiffness, and number of joint swelling among the groups. After the intervention, the number of joint tenderness, hand grip strength, duration of morning stiffness, number of joint swelling, and other joint function recovery in the rehabilitation group were significantly better than those in the reference group (P &lt; 0.05). The nursing satisfaction of the rehabilitation group was significantly higher than that of the reference group (P &lt; 0.05). Conclusion: Rehabilitation nursing intervention can accelerate the recovery of joint function and improve the living standard of patients with rheumatoid arthritis.

The Influence of Explosive and Rock Mass Properties on Blast Damage in a Single-Hole Blasting

In rock blasting for mining production, stress waves play a major role in rock fracturing, along with explosive gases. Better energy distribution improves fragmentation and safety, lowers production costs, increases productivity, and controls ore losses and dilution. Blast outcomes vary significantly depending on the choice of the explosive and the properties of the rock mass encountered. This study analyzes the effects of rock mass and explosive properties on blast outcomes via numerical simulation using data from the case study, and later validates the simulation results from the field blast fragmentation. The findings suggest that, for a given set of rock properties, the choice of explosive has a major influence on the resulting fragmentation. Strong explosives (high VOD and detonation pressure) favor large fracture extents in hard rocks, while weaker explosives offer a better distribution of explosive energy and fractures. The presence of rock structures such as rock contacts and joints influences the propagation of stress waves and fractures depending on the structures’ material properties, the intensity and orientations, and the direction and strength of the stress wave. When the stress wave encounters a contact depending on its direction, it is enhanced when traveling from soft to hard and attenuates in the opposite direction. The ability of the stress wave to cause fracturing on the opposite side of the contact depends on the intensity of the transmitted wave and the strength of the rock. Transmitted wave intensity is a function of the strength of the incident wave and the impedance difference between the interface materials. The presence of joints in the rock mass affects the propagation of the stress wave, mainly depending on the infill material properties and the angle at which the stress wave approaches the joint. Less compressible, higher stiffness joints transmit more energy. More energy is also transmitted in the areas where the stress wave hits the joint perpendicularly. Joints parallel to the free face offer additional fracturing on the opposite side of the joint. Other parameters, such as the joint width, continuity, fracture frequency, and the distance from the charge, enhance the effects. To achieve effective fragmentation, the blast design should mitigate the effect of variability in the rock mass via explosive selection and pattern design to ensure adequate energy distribution within the limits of geometric design.