Classifying Self-Reported Rheumatoid Arthritis Flares Using Daily Patient-Generated Data From a Smartphone App: Exploratory Analysis Applying Machine Learning Approaches

BACKGROUND

The ability to predict rheumatoid arthritis (RA) flares between clinic visits based on real-time, longitudinal patient-generated data could potentially allow for timely interventions to avoid disease worsening.

OBJECTIVE

This exploratory study aims to investigate the feasibility of using machine learning methods to classify self-reported RA flares based on a small data set of daily symptom data collected on a smartphone app.

METHODS

Daily symptoms and weekly flares reported on the Remote Monitoring of Rheumatoid Arthritis (REMORA) smartphone app from 20 patients with RA over 3 months were used. Predictors were several summary features of the daily symptom scores (eg, pain and fatigue) collected in the week leading up to the flare question. We fitted 3 binary classifiers: logistic regression with and without elastic net regularization, a random forest, and naive Bayes. Performance was evaluated according to the area under the curve (AUC) of the receiver operating characteristic curve. For the best-performing model, we considered sensitivity and specificity for different thresholds in order to illustrate different ways in which the predictive model could behave in a clinical setting.

RESULTS

The data comprised an average of 60.6 daily reports and 10.5 weekly reports per participant. Participants reported a median of 2 (IQR 0.75-4.25) flares each over a median follow-up time of 81 (IQR 79-82) days. AUCs were broadly similar between models, but logistic regression with elastic net regularization had the highest AUC of 0.82. At a cutoff requiring specificity to be 0.80, the corresponding sensitivity to detect flares was 0.60 for this model. The positive predictive value (PPV) in this population was 53%, and the negative predictive value (NPV) was 85%. Given the prevalence of flares, the best PPV achieved meant only around 2 of every 3 positive predictions were correct (PPV 0.65). By prioritizing a higher NPV, the model correctly predicted over 9 in every 10 non-flare weeks, but the accuracy of predicted flares fell to only 1 in 2 being correct (NPV and PPV of 0.92 and 0.51, respectively).

CONCLUSIONS

Predicting self-reported flares based on daily symptom scorings in the preceding week using machine learning methods was feasible. The observed predictive accuracy might improve as we obtain more data, and these exploratory results need to be validated in an external cohort. In the future, analysis of frequently collected patient-generated data may allow us to predict flares before they unfold, opening opportunities for just-in-time adaptative interventions. Depending on the nature and implication of an intervention, different cutoff values for an intervention decision need to be considered, as well as the level of predictive certainty required.

Effects of walking speeds on lower extremity kinematic synergy in toe vertical position control: An experimental study

BACKGROUND

This study aimed to investigate whether lower limb joints mutually compensate for each other, resulting in motor synergy that suppresses toe vertical position fluctuation, and whether walking speeds affect lower limb synergy.

METHODS

Seventeen male university students walked at slow (0.85 ± 0.04 m/s), medium (1.43 ± 0.05 m/s) and fast (1.99 ± 0.06 m/s) speeds on a 15-m walkway while lower limb kinematic data were collected. Uncontrolled manifold analysis was used to quantify the strength of synergy. Two-way (speed × phase) repeated-measures analysis of variance was used to analyze all dependent variables.

RESULTS

A significant speed-by-phase interaction was observed in the synergy index (SI) (P  < .001). At slow walking speeds, subjects had greater SI during mid-swing (P  < .001), while at fast walking speeds, they had greater SI during early-swing (P  < .001). During the entire swing phase, fast walking exhibited lower SI values than medium (P  = .005) and slow walking (P  = .027).

CONCLUSION

Kinematic synergy plays a crucial role in controlling toe vertical position during the swing phase, and fast walking exhibits less synergy than medium and slow walking. These findings contribute to a better understanding of the role of kinematic synergy in gait stability and have implications for the development of interventions aimed at improving gait stability and reducing the risk of falls.

Estimation of the forces exerted on the limb long bones of a white rhinoceros (Ceratotherium simum) using musculoskeletal modelling and simulation

Heavy animals incur large forces on their limb bones, due to the transmission of body weight and ground reaction forces, and the contractions of the various muscles of the limbs. This is particularly true for rhinoceroses, the heaviest extant animals capable of galloping. Several studies have examined their musculoskeletal system and the forces their bones incur, but no detailed quantification has ever been attempted. Such quantification could help understand better the link between form and function in giant land animals. Here we constructed three-dimensional musculoskeletal models of the forelimb and hindlimb of Ceratotherium simum, the heaviest extant rhino species, and used static optimisation (inverse) simulations to estimate the forces applied on the bones when standing at rest, including magnitudes and directions. Overall, unsurprisingly, the most active muscles were antigravity muscles, which generate moments opposing body weight (thereby incurring the ground reaction force), and thus keep the joints extended, avoiding joint collapse via flexion. Some muscles have an antigravity action around several joints, and thus were found to be highly active, likely specialised in body weight support (ulnaris lateralis; digital flexors). The humerus was subjected to the greatest amount of forces in terms of total magnitude; forces on the humerus furthermore came from a great variety of directions. The radius was mainly subject to high-magnitude compressive joint reaction forces, but to little muscular tension, whereas the opposite pattern was observed for the ulna. The femur had a pattern similar to that of the humerus, and the tibia's pattern was intermediate, being subject to great compression in its caudal side but to great tension in its cranial side (i.e. bending). The fibula was subject to by far the lowest force magnitude. Overall, the forces estimated were consistent with the documented morphofunctional adaptations of C. simum's long bones, which have larger insertion areas for several muscles and a greater robusticity overall than those of lighter rhinos, likely reflecting the intense forces we estimated here. Our estimates of muscle and bone (joint) loading regimes for this giant tetrapod improve the understanding of the links between form and function in supportive tissues and could be extended to other aspects of bone morphology, such as microanatomy.

A review of modification methods, joints and self-healing methods of adhesive for aerospace

In recent years, the adhesive technology has been widely used in the production of high-strength joins and precise positioning of various materials, such as metals, glass and composite materials. The adhesive technology has become a promising assembly process in the aerospace field due to its versatility, low creep and high damage tolerance. However, the reliability and predictability of adhesive bonding still require further development due to the complex operating conditions involved. Therefore, this article reviews and discusses the latest advances in aerospace adhesive technology, such as methods for improving bonding performance, bonding techniques (including joints structure and failure modes) and self-healing adhesive layers. Additionally, the current research results are summarised, and possible development trends and research directions in the field of adhesive bonding are prospected.

Comprehensive insights into rheumatoid arthritis: Pathophysiology, current therapies and herbal alternatives for effective disease management

Rheumatoid arthritis is a chronic autoimmune inflammatory disease characterized by immune response overexpression, causing pain and swelling in the synovial joints. This condition is caused by auto-reactive antibodies that attack self-antigens due to their incapacity to distinguish between self and foreign molecules. Dysregulated activity within numerous signalling and immunological pathways supports the disease's development and progression, elevating its complexity. While current treatments provide some alleviation, their effectiveness is accompanied by a variety of adverse effects that are inherent in conventional medications. As a result, there is a deep-rooted necessity to investigate alternate therapeutic strategies capable of neutralizing these disadvantages. Medicinal herbs display a variety of potent bioactive phytochemicals that are effective in the complementary management of disease, thus generating an enormous potency for the researchers to delve deep into the development of novel phytomedicine against autoimmune diseases, although additional evidence and understanding are required in terms of their efficacy and pharmacodynamic mechanisms. This literature-based review highlights the dysregulation of immune tolerance in rheumatoid arthritis, analyses the pathophysiology, elucidates relevant signalling pathways involved, evaluates present and future therapy options and underscores the therapeutic attributes of a diverse array of medicinal herbs in addressing this severe disease.

Do Patients With Insulin-Dependent and Non-Insulin-Dependent Diabetes Have Different Risks for Complications After Total Ankle Arthroplasty?

BACKGROUND

Patients with diabetes undergoing total ankle arthroplasty tend to be at greater risk for complications than those without diabetes. However, the effect of diabetes severity and how it impacts the risk for perioperative complications is less clear. The purpose of this study was to compare (1) complications, (2) length of hospital stay, and (3) readmissions within 30 days for total ankle arthroplasty (TAA) patients without diabetes, patients with non-insulin-dependent diabetes, and patients with insulin-dependent diabetes.

METHODS

Using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database, a total of 1803 patients undergoing TAA between 2007 and 2019 were collected. The relationship between diabetes status (no diabetes [n = 1,589], insulin-dependent [n = 169], and non-insulin-dependent [n = 45]) and outcomes were compared. Multivariate linear regression models were used to adjust for confounding variables such as age, sex, race, body mass index, smoking, steroid use, hypertension, chronic obstructive pulmonary disease, anesthesia type, dyspnea, and outpatient status. Statistical significance was set at P <.05.

RESULTS

Insulin-dependent diabetes was an independent risk factor for increased odds of infection within 30 days (odds ratio 6.47, 95% CI 0.79-33.66; P = .043). Hospital length of stay was also increased in patients with non-insulin-dependent diabetes (β = 0.21, 95% CI 0.02-0.40; P = .031) and insulin-dependent diabetes (β = 0.40, 95% CI 0.04-0.76; P = .028). However, neither diabetic state demonstrated a statistically significant increase in readmissions or wound complications within 30 days.

CONCLUSION

Patients with insulin-dependent diabetes included in this cohort were at increased risk of having an infection within 30 days after TAA. Additionally, patients with diabetes status had an increased hospital length of stay. These results can inform patients on their potential outcomes after total ankle arthroplasty based on their diabetes status.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Expert United Kingdom consensus on the preservation of joint health in people with moderate and severe haemophilia A: A modified Delphi panel

AIM

For people with haemophilia A (PwHA), bleeding in the joints leads to joint damage and haemophilia-related arthropathy, impacting range of motion and life expectancy. Existing guidelines for managing haemophilia A support healthcare professionals (HCPs) and PwHA in their efforts to preserve joint health. However, such guidance should be reviewed, considering emerging evidence and consensus as presented in this manuscript.

METHODS

Fifteen HCPs experienced in the management of PwHA in the UK participated in a three-round Delphi panel. Consensus was defined at ≥70% of panellists agreeing or disagreeing for Likert-scale questions, and ≥70% selecting the same option for multiple- or single-choice questions. Questions not reaching consensus were revised for the next round.

RESULTS

26.8% (11/41), 44.8% (13/29) and 93.3% (14/15) of statements reached consensus in Rounds 1, 2 and 3, respectively. HCPs agreed that prophylaxis should be offered to patients with a baseline factor VIII (FVIII) level of ≤5 IU/dL and that, where there is no treatment burden, the aim of prophylaxis should be to achieve a trough FVIII level ≥15 IU/dL and maintain a longer period with FVIII levels of ≥20-30 IU/dL to provide better bleed protection. The aspirational goal for PwHA is to prevent all joint bleeds, which may be achieved by maintaining normalised (50-150 IU/dL) FVIII levels.

CONCLUSION

The panel of experts were largely aligned on approaches to preserving joint health in PwHA, and this consensus may help guide HCPs.

The assessment of Spondyloarthritis International Society Health Index (ASAS HI) in patients with spondyloarthritis - a single centre experience

Aim The Assessment of Spondyloarthritis International Society Health Index (ASAS HI) Croatian version was used to assess health and functioning of patients with spondyloarthritis (SpA) covering aspects of physical, emotional and social functioning. Methods A cross sectional study was conducted at the Clinic for Internal Diseases Tuzla from January to June 2021. Inclusion criteria: fulfilled the ASAS diagnostic criteria for SpA. Exclusion criteria: failure to fulfil the diagnostic criteria, acute infection, the use of antibiotics in the past month, malignancy, associated disorders, psychiatric disorders, pregnancy, patient's refusal to take part in the study. The Disease Activity Score with C reactive protein values (ASDAS-CRP) was assessed. Results Eighty three patients (43 male and 40 female) fulfilled the study criteria with median age of 54 years. The median value of ASDAS-CRP was 2.15, since ASAS HI had the median of 8 (interquartile range; IQR: 2-13) points. Patients with inactivity and with low disease activity had the ASAS HI median of 2 (IQR: 0-6) and 5 (IQR: 1-9) points, respectively. Significantly higher values of ASAS HI were found in patients with moderate and high disease activity, males (13.5 and 16) and females (13 and 14), respectively. The correlation between ASDAS-CRP and ASAS HI, (r=0.62; p<0.0009) was positive, statistically significant. However, the significant correlation between disease duration and ASAS HI values was not found (r=0.11; p=0.28). Conclusion The ASAS HI, Croatian version, is valid and reliable disease specific questionnaire for the assessment of health status in patients with SpA in the Bosnian speaking area.

Ultrasound evaluation of hemophilic arthropathy: a proposal of definitions in a changing landscape

The advent of novel effective treatments and the identification of the need to achieve a higher trough level for persons with hemophilia A and B have changed the landscape of management of these patients, allowing to change the target from survival and prevention of life-threatening complications to prevention of musculoskeletal complications and improvement of quality of life. Point-of-care musculoskeletal ultrasound imaging has also improved the early recognition of joint bleeding and the differential diagnosis of acute joint pain. In addition, joint ultrasound allows the evaluation of the severity of hemophilic arthropathy in terms of synovitis and cartilage and bone damage. However, a lack of standardization in the definition of ultrasound elementary lesions of hemophilic arthropathy may lead to confusion and an incorrect evaluation of the presence and progression of joint damage. Here, we propose to start a standardization and validation process for ultrasound definitions of hemophilic arthropathy that has been planned to become a project within the Factor VIII/IX Standardization Subcommittee of the International Society on Thrombosis and Haemostasis Scientific and Standardization Committee.

Pediatric Psoriasis with or without Arthritis: Does It Make a Difference?

BACKGROUND

Psoriasis and psoriatic arthritis can present simultaneously or separately in children and may pose a diagnostic challenge.

OBJECTIVE

To compare the dermatological manifestations in pediatric psoriatic patients with and without arthritis.

METHODS

A retrospective case-control study of psoriatic patients ≤ 18 years old at Sheba Medical Center was conducted between 2011 and 2021. Patients with psoriatic arthritis versus psoriasis-only were compared according to body surface area (BSA) involvement, cutaneous distribution, severity of skin disease, response to treatment and related side effects.

RESULTS

The study cohort included 29 psoriatic arthritis and 64 psoriasis-only patients matched by age and sex. The psoriasis-only group had a significantly higher mean BSA (19.7%, SD ± 18.7) than the psoriatic arthritis group (6.1%, SD ± 11.4), (p = 0.029). The skin distribution differed with the psoriasis group showing more involvement of the extremities, scalp, trunk, and genitals. Both groups primarily experienced partial responses to methotrexate, whereas the psoriasis group mainly saw complete responses to biologics. Adverse events were rare, with a higher incidence in the psoriasis group.

CONCLUSION

This retrospective study highlights the differences in cutaneous disease characteristics, severity, and treatment response in pediatric patients with psoriasis and psoriatic arthritis, providing valuable insights for diagnosis and disease course in the pediatric population.

Ultrasound in anti-CCP+ at-risk individuals without clinical synovitis: development of a novel 6-joint protocol for feasible risk prediction

OBJECTIVES

To investigate, in anti-cyclic citrullinated peptide antibody positive individuals with musculoskeletal symptoms but no clinical synovitis (CCP+ at-risk), the additional value of ultrasound (US) for the prediction of inflammatory arthritis (IA). Furthermore, to define a concise US protocol for feasible risk prediction.

METHODS

Demographic and clinical data were collected in 417 CCP+ at-risk (Leeds CCP cohort) with a baseline US scan assessing synovitis and bone erosions in 36 joints, and a follow-up duration ≥24 months. Multivariable binary regression models for IA development at 24 months evaluated routine clinical variables associated with IA alone ("clinical" model) and combined with a 36-joint US scanning protocol ("clinical-US extended" model). A "clinical-US short" model was developed.

RESULTS

At 24 months, 92/417 (22.1%) CCP+ at-risk developed IA (median time: 7 months, IQR : 3-12). The "clinical-US extended" model performed better than the "clinical" model (AUC 0.788 vs AUC 0.731 respectively, p< 0.001) with an odds ratio for IA development of 3.18 (95% IC 1.80-5.63) for US synovitis and 2.54 (95% IC 1.21-5.37) for bone erosions. The "clinical-US short" model, which retained the wrists, knees and MTP5 joints, performed better (AUC 0.782) than the "clinical" model (p< 0.001) and similarly (difference in Akaike information criteria <2) to the "clinical-US extended" model.

CONCLUSIONS

US provides valuable information for predicting progression to IA in CCP+ individuals both alone and in addition to clinical variables. US synovitis was associated with a threefold increase risk of IA development. A concise US protocol of 6 joints provides clinically feasible risk prediction in CCP+ at-risk.

Rheumatoid Arthritis Has Won the Battle but Not the War: How Many Joints Will We Save Tomorrow?

Rheumatoid arthritis refers to joint diseases of unclear etiology whose final stages can lead to unbearable pain and complete immobility of the affected joints. As one of the most widely known diseases of the joints, it serves as a study target for a large number of research groups and pharmaceutical companies. Modern treatment with anti-inflammatory drugs, including janus kinase (JAK) inhibitors, monoclonal antibodies, and botanicals (polyphenols, glycosides, alkaloids, etc.) has achieved some success and hope for improving the course of the disease. However, existing drugs against RA have a number of side effects which push researchers to elaborate on more selective and effective drug candidates. The avant-garde of research, which aims to develop treatment of rheumatoid arthritis using antisense oligonucleotides along with nonsteroidal drugs and corticosteroids against inflammation, increases the chances of success and expands the arsenal of drugs. The primary goal in the treatment of this disease is to find therapies that allow patients with rheumatoid arthritis to move their joints without pain. The main purpose of this review is to show the victories and challenges for the treatment of rheumatoid arthritis and the tortuous but promising path of research that aims to help patients experience the joy of freely moving joints without pain.

Surgical accuracy of image-free versus image-based robotic-assisted total knee arthroplasty

BACKGROUND

This study investigated the accuracy in achieving proper lower limb alignment and component positions after total knee replacement (TKR) with image-free and image-based robotic-assisted TKR.

METHODS

A total of 129 patients (166 knees) suffering from end-stage knee arthritis who underwent TKA operated by robotic-assisted surgery between the years 2018 and mid-2021 were recruited. Radiological outcomes were compared between image-free and image-based robotic-assisted surgical systems.

RESULTS

There were significant differences between the two robotic systems when comparing the mean planned component alignment and the mean measured alignment on radiographs, in which the image-free robotic-assisted system was more varus, whereas the image-based robotic-assisted system was more valgus for both the mean femoral and tibial component coronal alignment (p < 0.001). For tibial component sagittal alignment, the image-based group had a larger deviation from the planned posterior slope (p < 0.001).

CONCLUSION

Image-free and image-based robotic assisted TKR had differing accuracy in femoral and tibial alignment.

LincRNA-EPS Alleviates Inflammation in TMJ Osteoarthritis by Binding to SRSF3

Temporomandibular joint osteoarthritis (TMJOA) is a common inflammatory disease that can cause pain, cartilage degradation, and subchondral bone loss. However, the key regulatory factors and new targets for the treatment of TMJOA have yet to be determined. Long noncoding RNAs (lncRNAs) have shown remarkable potential in regulating tissue homeostasis and disease development. The long intergenic RNA-erythroid prosurvival (lincRNA-EPS) is reported to be an effective inhibitor of inflammation, but its role in TMJOA is unexplored. Here, we found that lincRNA-EPS is downregulated and negatively correlated with inflammatory factors in the condyles of TMJOA mice. LincRNA-EPS knockout aggravated inflammation and tissue destruction after TMJOA modeling. The in vitro studies confirmed that loss of lincRNA-EPS facilitated inflammatory factor expression in condylar chondrocytes, while recovered expression of lincRNA-EPS showed anti-inflammatory effects. Mechanistically, RNA sequencing revealed that the inflammatory response pathway nuclear factor-kappa B (NF-κB) was mostly affected by lincRNA-EPS deficiency. Moreover, lincRNA-EPS was proved to effectively bind to serine/arginine-rich splicing factor 3 (SRSF3) and inhibit its function in pyruvate kinase isoform M2 (PKM2) formation, thus restraining the PKM2/NF-κB pathway and the expression of inflammatory factors. In addition, local injection of the lincRNA-EPS overexpression lentivirus significantly alleviated inflammation, cartilage degradation, and subchondral bone loss in TMJOA mice. Overall, lincRNA-EPS regulated the inflammatory process of condylar chondrocytes by binding to SRSF3 and showed translational application potential in the treatment of TMJOA.

Prophylaxis with a recombinant factor VIII Fc in hemophilia A: long-term follow-up on joint health, efficacy, and safety from phase 3 studies in children and adults

Background

Recurrent joint bleeds are a major cause of morbidity in severe hemophilia. Prophylaxis with efmoroctocog alfa (a recombinant factor VIII Fc fusion protein, [rFVIIIFc]) has demonstrated benefits beyond bleed control, including joint health maintenance.

Objectives

To assess long-term efficacy and safety of rFVIIIFc prophylaxis in severe hemophilia A in phase 3 pivotal (A-LONG/Kids A-LONG) and extension (ASPIRE) studies.

Methods

Longitudinal analysis included pooled data from A-LONG/Kids A-LONG and ASPIRE. Subgroup analyses investigated outcomes in modified Hemophilia Joint Health Score or Hemophilia Joint Health Score and target joints in subjects with 4 to 5 years follow-up on individualized prophylaxis (IP), and those with the highest annualized bleeding rate (ABR) quartile during Year 1 of IP.

Results

Overall, rFVIIIFc consumption remained stable and low ABRs were maintained, with a median treatment duration of 4.2/3.4 years in subjects from A-LONG/Kids A-LONG, respectively. Median overall ABR also remained low (1.0-2.0) in subjects on IP for 4 to 5 years. Sustained improvements in modified Hemophilia Joint Health Score or Hemophilia Joint Health Score were demonstrated over a median follow-up of 3.7 years. In subjects from A-LONG/Kids A-LONG, 99.6% (n = 234)/100% (n = 9) of evaluable baseline target joints were resolved, with no recurrence in 95%/100% of target joints. In IP subjects within the highest ABR quartile in Year 1, continued improvements were observed over a median follow-up of 4.3 years in ABR and joint health, without increased factor consumption. No inhibitors or treatment-related serious adverse events were reported.

Conclusion

Previously treated subjects of all ages receiving long-term prophylaxis with rFVIIIFc had sustained clinical benefits, including improved joint health and low ABR.

T2 mapping magnetic resonance imaging of cartilage in hemophilia

Background

In hemophilia, recurrent hemarthrosis may lead to irreversible arthropathy. T2 mapping MRI may reflect cartilage changes at an earlier reversible stage of arthropathy as opposed to structural MRI.

Objectives

To evaluate interval changes of T2 mapping compared with the International Prophylaxis Study Group (IPSG) structural MRI scores of ankle cartilage in boys with hemophilia receiving prophylaxis.

Methods

Eight boys with hemophilia A (median age, 13; range, 9-17 years), 7 age- and sex-matched healthy boys (controls, median age, 15; range, 7-16 years). A multiecho spin-echo T2-weighted MRI sequence at 3.0T was used to obtain T2 maps of cartilage of boys with hemophilia and controls. Structural joint status was evaluated using the IPSG MRI score.

Results

T2 relaxation times of ankle cartilage increased significantly over time in both persons with hemophilia and controls (P = .002 and P = .00009, respectively). Changes in T2 relaxation time strongly correlated with changes in IPSG cartilage scores (rs = 0.93 to rs = 0.78 [P = .0007 to P = .023]), but not with changes in age (P = .304 to P = .840). Responsiveness of T2 relaxation times were higher than that of IPSG cartilage scores, with standardized response means >1.4 for T2 mapping in all regions-of-interest compared with 0.84 for IPSG cartilage scores. Baseline T2 relaxation time strongly correlated with timepoint 2 IPSG cartilage score (rs = 0.93 to rs = 0.82 [P = .001 to P = .012]) and T2 relaxation time (rs = 0.98 to rs = 0.88 [P = .00003 to P = .004]) changes in most regions-of-interest.

Conclusion

T2 mapping shows sensitivity to biochemical changes in cartilage prior to detectable damage using conventional MRI, offering potential for early detection of bleed-related cartilage damage in boys with hemophilia.

Transforming Orthopedic Joint Surgeries: The Role of Artificial Intelligence (AI) and Robotics

The landscape of orthopedic joint surgeries, specifically total hip arthroplasty (THA) and total knee arthroplasty (TKA), is rapidly changing, and artificial intelligence (AI) along with robotics is at the helm of this transformation. These technologies, working synergistically, have introduced unprecedented levels of precision and personalization to surgical procedures, thereby significantly enhancing patient outcomes. In this editorial, we explore the changing perspectives of orthopedic surgeons toward AI and robotics and dissect the incorporation of these technologies in surgeries, their associated advantages, their inherent limitations, and potential future prospects. We draw from a host of recent studies to provide a comprehensive understanding of how these transformative technologies can augment surgical performance and patient care.

Dalbavancin in Bone and Joint Infections: A Systematic Review

BACKGROUND

Approved for acute bacterial skin and skin structure infections, dalbavancin (DBV) has gradually acquired over the years a role as an off-label treatment for several infections caused by Gram-positive bacteria even in other anatomical sites. Osteoarticular (OA) infections are one of the most difficult-to-treat infections and, since the absence of recommendations, clinicians use different and heterogenic DBV dosing schedule regimens for the off-label treatment of osteomyelitis, spondylodiscitis, and septic arthritis. Our aim is to systematically review the current literature to describe DBV administration schedules and their outcome in OA infections.

METHODS

According to the 2020 updated PRISMA guidelines, all peer-reviewed articles regarding the use of DBV in OA infections were included. We conducted a literature search on PubMed and Cochrane Controlled Trials.

RESULTS

A total of 23 studies and 450 patients were included, prevalently male (144/195, 73.8%) and diabetic (53/163, 32.5%). Overall, 280 (280/388, 72.2%) osteomyelitis, 79 (79/388, 20.4%) spondylodiscitis, and 29 (29/388, 7.5%) septic arthritis were considered. Staphylococcus aureus (164/243, 67.5%) was the most common pathogen isolated. A previous treatment failure (45/96, 46.9%) was the main reason for a switch to a long-acting antibiotic. Most patients were successfully cured with DBV (318/401, 79.3%). A source control was performed in most patients with a favourable outcome (80.4%), while MRSA was prevalently isolated in people with an unfavourable outcome (57%). While a higher percentage of success was found in people who received three doses of DBV 1 week apart (92.3%), a higher rate of treatment failure was recorded in cases of when the DBV cycle was composed of less than two or more than four doses (27.8%).

CONCLUSIONS

DBV has shown to be effective as a treatment for OA infections. The most favourable outcome was found in patients receiving three doses of DBV and with an adequate surgical management prior to antibiotic treatment. Although a rigorous administration schedule does not exist, DBV is a viable treatment option in the management of OA infections.

Economic Evaluations of Digital Health Interventions for the Management of Musculoskeletal Disorders: Systematic Review and Meta-Analysis

BACKGROUND

Musculoskeletal disorders (MSDs) are widespread in many countries and their huge burden on the society has necessitated innovative approaches such as digital health interventions. However, no study has evaluated the findings of cost-effectiveness of these interventions.

OBJECTIVE

This study aims to synthesize the cost-effectiveness of digital health interventions for people with MSDs.

METHODS

Electronic databases including MEDLINE, AMED, CIHAHL, PsycINFO, Scopus, Web of Science, and Centre for Review and Dissemination were searched for cost-effectiveness of digital health published between inception and June 2022 following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. References of all retrieved articles were checked for relevant studies. Quality appraisal of the included studies was performed using the Quality of Health Economic Studies (QHES) instrument. Results were presented using a narrative synthesis and random effects meta-analysis.

RESULTS

A total of 10 studies from 6 countries met the inclusion criteria. Using the QHES instrument, we found that the mean score of the overall quality of the included studies was 82.5. Included studies were on nonspecific chronic low back pain (n=4), chronic pain (n=2), knee and hip osteoarthritis (n=3), and fibromyalgia (n=1). The economic perspectives adopted in the included studies were societal (n=4), societal and health care (n=3), and health care (n=3). Of the 10 included studies, 5 (50%) used quality-adjusted life-years as the outcome measures. Except 1 study, all the included studies reported that digital health interventions were cost-effective compared with the control group. In a random effects meta-analysis (n=2), the pooled disability and quality-adjusted life-years were -0.176 (95% CI -0.317 to -0.035; P=.01) and 3.855 (95% CI 2.023 to 5.687; P<.001), respectively. The meta-analysis (n=2) for the costs was in favor of the digital health intervention compared with control: US $417.52 (95% CI -522.01 to -313.03).

CONCLUSIONS

Studies indicate that digital health interventions are cost-effective for people with MSDs. Our findings suggest that digital health intervention could help improve access to treatment for patients with MSDs and as a result improve their health outcomes. Clinicians and policy makers should consider the use of these interventions for patients with MSDs.

TRIAL REGISTRATION

PROSPERO CRD42021253221; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=253221.

Poor correlation between biomarkers and MRI-detected joint damage in a cross-sectional study of persons with nonsevere hemophilia A (DYNAMO study)

BACKGROUND

Persons with nonsevere hemophilia A (NSHA) experience less frequent joint bleeding than persons with severe hemophilia A, but may still develop joint damage. Biomarkers of cartilage and synovial remodeling can reflect ongoing pathologic processes that may precede or coincide with damage on joint imaging. If so, biomarkers may be an important diagnostic tool for joint damage in NSHA.

OBJECTIVE

To assess the correlation between biomarkers and MRI-detected joint damage in persons with NSHA.

METHODS

In a cross-sectional study, men with NSHA (factor VIII [FVIII], 2-35 IU/dL) were included. Participants underwent magnetic resonance imaging of elbows, knees, and ankles and blood and urine sampling for biomarker analysis on a single visit. The following biomarker(s) were analyzed in urine: CTX-II or serum: cartilage oligomeric matrix protein, chondroitin sulfate 846, vascular cell adhesion molecule 1, osteopontin (OPN), neo-epitope of MMP -mediated degradation of type II collagen, N-terminal propeptide of type II collagen, collagen type IV M, and propetide of type IV collagen. Spearman's rank correlations were calculated between these biomarkers and the total International Prophylaxis Study group (IPSG) score, soft-tissue subscore, and osteochondral subscore.

RESULTS

In total, 48 persons with NSHA were included. Median age was 43 years (range, 24-55 years) and median FVIII was 10 IU/dL (IQR, 4-16 IU/dL). The median IPSG score was 4 (IQR, 2-9). Median IPSG soft-tissue subscores were 3 (IQR, 2-4) and osteochondral subscores were 0 (IQR, 0-4). No strong correlations were found between the studied biomarkers, total IPSG score, subsequent soft-tissue, and osteochondral subscores.

CONCLUSIONS

In this study, selected biomarkers indicative of different aspects of hemophilic arthropathy showed no consistent correlation with IPSG scores. This suggests that systemically measured biomarkers are currently not suitable for identifying milder joint damage in NSHA, as observed on magnetic resonance imaging.

Accuracy of Intraarticular Injections: Blind vs. Image Guided Techniques-A Review of Literature

Intra-articular injections are widely used for diagnostic and therapeutic purposes of joint pathologies throughout the body. These injections can be performed blind by utilizing anatomical landmarks or with the use of imaging modalities to directly visualize the joint space during injections. This review of the literature aims to comprehensively identify differences in the accuracy of intra-articular injections via palpation vs. image guidance in the most commonly injected joints in the upper and lower extremities. To our knowledge, there are no such comprehensive reviews available. A narrative literature review was performed using PubMed and Google Scholar databases to identify studies focusing on the accuracy of blind or image-guided intra-articular injections for each joint. A total of 75 articles was included in this review, with blind and image-guided strategies being discussed for the most commonly injected joints of the upper and lower extremities. Varying ranges of accuracy with blind and image-guided modalities were found throughout the literature, though an improvement in accuracy was seen in nearly all joints when using image guidance. Differences are pronounced, particularly in deep joints such as the hip or in the small joints such as those in the hand or foot. Image guidance is a useful adjunct for most intra-articular injections, if available. Though there is an increase in accuracy in nearly all joints, minor differences in accuracy seen in large, easily accessed joints, such as the knee, may not warrant image guidance.

Haemophilia joint health score (HJHS) usage, patterns and outcome data in patients with haemophilia A and haemophilia B in Australia: A descriptive study using the Australian Bleeding Disorders Registry (ABDR)

INTRODUCTION

Assessment of joint health is an essential component of haemophilia management. A variety of clinical tools have been developed to standardise this assessment process. One such tool, the Haemophilia Joint Health Score (HJHS), is embedded for use within the Australian Bleeding Disorders Registry (ABDR). This provides a unique opportunity to analyse patterns of tool usage as well as associations between scores, demographics and clinical outcome factors.

AIMS

To characterise clinician practices regarding use of HJHS in routine clinical assessment of persons with haemophilia (PWH), to examine relationships between HJHS, and age, inhibitor status and body mass index (BMI), and to identify potential barriers to HJHS tool usage.

METHODS

A national, retrospective study was conducted using data extracted from the ABDR between 2014 and 2020, complemented by a qualitative questionnaire exploring haemophilia treatment centre (HTC) structure, resourcing and clinician perspectives about HJHS.

RESULTS

28.1% (622/2220) of PWH had at least one HJHS recorded in the ABDR during the defined study period (546 haemophilia A, 76 haemophilia B). HJHS were recorded more in children than adults and performed more in severe than non-severe haemophilia. Multivariate analysis demonstrated significant association of age, severity and inhibitor status with HJHS. No association was identified between BMI and HJHS. Qualitative surveys revealed significant variation in physiotherapy funding, availability and methods of tool use between HTCs.

CONCLUSION

This study provides valuable insights into joint health assessment in Australia. It improved our understanding of factors influencing long-term joint outcomes. Practical limitations of HJHS tool were also discussed.

Radiological manifestation of avascular necrosis (AVN) in sickle cell disease (SCD): a review of diagnostic imaging

Symptomatic avascular necrosis (AVN) imposes a higher risk for acute care consumption in adults living with SCD. Symptomatic AVN, have higher rates of visits to the emergency department, higher rates of admissions, and longer lengths of stay in hospitals. Properly timed diagnosis and early interventions can reduce morbidity and enhance the quality of life in these patients. Vaso-occlusion secondary to sickling leads to osteonecrosis of the joint/bone (AVN, dactylitis) and invites infection (osteomyelitis and septic arthritis). Understanding and awareness of the imaging features related to this major morbidity complication are essential for early diagnosis and prompt management. In about half of the patients with SCD, AVN can lead to chronic pain, particularly in the head of the femur and humerus. Humeral and femoral head AVN tend to be linked with each other.  Vertebral bone compression and collapse secondary to AVN have also been reported.  The diagnosis of AVN must be accurate, as the condition is complex requiring specific treatment according to the grade of bone and joint involvement. There are several classifications or staging systems used for grading bone and joint involvement. Knowledge of the image patterns and grade of affection in different joints and bones and the degree of progression of AVN lesions can markedly improve management decisions on AVN-specific surgical versus non-surgical interventions and improve patient outcomes. The aim of this report is to summarize the different imaging techniques and their role in the proper/early diagnosis and follow up of patients with AVN with detailed examples of the common sites involved.

Intermediate-weighted MRI with fat suppression (IW-FS): diagnostic performance for bone marrow edema and erosion detection in axial spondyloarthritis

BACKGROUND

Bone marrow edema (BME) and erosion of the sacroiliac joint are both key lesions for diagnosing axial spondyloarthritis (axSpA) on magnetic resonance imaging (MRI).

PURPOSE

To qualitatively and quantitatively compare intermediate-weighted MRI with fat suppression (IW-FS) with T2-weighted short tau inversion recovery (T2-STIR) in assessment of sacroiliac BME and erosion in axSpA.

MATERIAL AND METHODS

Patients aged 18-60 years with axSpA were prospectively enrolled. All patients underwent a 3.0-T MRI examination of the sacroiliac joints. Para-coronal IW-FS, T2-STIR, and T1-weighted (T1W) images were acquired. BME and erosion were scored by two readers in consensus on IW-FS and STIR using a modified Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system. Consensus scores on T1WI were used as the reference for erosion. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured for BME.

RESULTS

In total, 49 patients (mean age=33.4 ± 7.6 years) were included. More patients were scored as having BME on T2-STIR (36 vs. 29, P = 0.016). SPARCC-BME score on IW-FS was lower than that acquired on T2-STIR (mean, 11.5 vs. 14.7, P = 0.002). SNR and CNR of BME were both lower on IW-FS than on T2-STIR (mean SNR, 118 vs. 218, P < 0.001; mean CNR, 44 vs. 137, P < 0.001). The sensitivity of erosion detection was higher on IW-FS (83%) than on T2-STIR (54%, P = 0.006).

CONCLUSION

IW-FS is not sufficient for BME detection using T2-STIR as the reference standard in patients with axSpA. IW-FS has a much higher sensitivity than T2-STIR for erosion detection in the sacroiliac joint.

A latent class analysis of patterns of tobacco and cannabis use in Australia and their health-related correlates

INTRODUCTION

The shifting landscape in Australia's tobacco and cannabis policies and emerging new products and modes of administration may increase experimentation and the risks of addiction to these drugs.

METHODS

We analysed cross-sectional data from the 2019 National Drug Strategy and Household Survey (n = 22,015) of Australians aged 14 and above. Latent class analysis was used to identify distinct groups based on types of tobacco and cannabis products used. The socio-demographic, health-rated correlates and past-year substance use of each latent class was examined.

RESULTS

A four-class solution was identified: co-use of tobacco and cannabis (2.4%), cannabis-only (5.5%), tobacco-only (8.0%) and non-user (84.0%). Males (odds ratio [OR] range 1.5-2.9), younger age (OR range 2.4-8.4), moderate to high psychological distress (OR range 1.3-3.0), using illicit substances in the last year (OR range 1.41-22.87) and high risk of alcohol use disorder (OR range 2.0-21.7) were more likely to be in the tobacco/cannabis use classes than non-users. Within the co-use class, 78.4% mixed tobacco with cannabis and 89.4% had used alcohol with cannabis at least once.

DISCUSSION AND CONCLUSIONS

Approximately 16% of respondents used tobacco or cannabis, or both substances, and no major distinct subgroups were identified by the use of different product types. Mental health issues and the poly-substance use were more common in the class who were co-users of cannabis and tobacco. Existing policies need to minimise cannabis and tobacco-related harms to reduce the societal burden associated with both substances.

Seismic Tests of Full Scale Reinforced Concrete T Joints with Light External Continuous Composite Rope Strengthening-Joint Deterioration and Failure Assessment

Beam-column connections (joints) are one of the most critical elements which govern the overall seismic behavior of reinforced concrete (RC) structures. Especially in buildings designed according to previous generation codes, joints are often encountered with insufficient transverse reinforcement detailing, or even with no stirrups, leading to brittle failure. Therefore, externally bonded composite materials may be applied, due to the ease of application, low specific weight and corrosion-free properties. The present work assesses the seismic performance of insufficiently reinforced large-scale T beam-column connections with large and heavily reinforced beams. The joints receive externally bonded NSM X-shaped composite ropes with improved versatile continuous detailing. The columns are subjected to low normalized axial load, while the free end of the beam is subjected to transverse displacement reversals. Different failure criteria are investigated, based on the beam free-end transverse load, as well as on the joint region shear deformations, to critically assess the structural performance of the subsystem. The experimental investigation concludes that cyclic loading has a detrimental effect on the performance of the joint. Absence of an internal steel stirrup leads to earlier deterioration of the joint. The unstrengthened specimens disintegrate at 2% drift, which corresponds to 34 mm beam-end displacement, and shear deformation of the joint equal to 30 × 10^-4 rad. The composite strengthening, increases the structural performance of the joint up to 4% drift which corresponds to 68 mm of beam-end displacement and shear deformation of the joint equal to 10 × 10^-4 rad. The investigated cases of inadequate existing transverse reinforcement in the joint and light external FRP strengthening provide a unique insight into the required retrofits to achieve different levels of post-yielding displacement ductility under seismic loading at 2%, 3% and 4% drift. It allows for future analytical refinements toward reliable redesign analytical models.

Applications of artificial intelligence in clinical management, research and health administration: imaging perspectives with a focus on hemophilia

INTRODUCTION

Joints of persons with hemophilia are frequently affected by repetitive hemarthrosis. In this paper concepts, perks and quirks of the use of artificial intelligence (AI), machine learning (ML) and deep learning are reviewed within clinical and research contexts of hemophilia and other blood-induced disorders' patient care, targeted to the imaging diagnosis of hemophilic joints, under the perspective of different stakeholders (radiologists, hematologists, nurses, physiotherapists, technologists, researchers, managers and patients/caregivers).

AREAS COVERED

Rubrics that determine the suitability of the utilization of AI in blood-induced disorders' patient care, including diagnosis and follow-up of patients are discussed, focusing on features in which AI can replace or augment the role of radiology in the clinical management and in research of patients. Insights on features in the design and conduct of AI projects in which the human intervention remains critical are provided.

EXPERT OPINION

The author discusses research concepts in radiogenomics, and challenges of the utilization of AI in different healthcare fields such as patient safety, data sharing and privacy regulations, workforce education and future jobs' shortage. Finally, the author proposes alternatives and potential solutions to mitigate challenges in successfully deploying ML algorithms into clinical practice.

Multiligament stifle injury, a multicenter retrospective study in 26 dogs

OBJECTIVES

To describe multiligament stifle injury in dogs and report complications and long-term outcomes.

METHODS

Medical records of dogs surgically treated for multiligament stifle injury were reviewed from six veterinary hospitals. Long-term follow-up was collected from referring veterinarians.

RESULTS

Twenty-six client-owned dogs and 26 stifles were included. Road traffic accidents and limb entrapment were the most common causes of injury. Cranial cruciate and lateral collateral ligament rupture was the most common combination of injury (10 cases). The caudal cruciate ligament was damaged in 12/23 cases but was surgically addressed in only 2 cases. Cranial cruciate ligament rupture was present in all cases and was managed using TPLO (6 cases), extracapsular suture (15 cases) and TTA (2 cases). Postoperative immobilisation with a transarticular external skeletal fixator was used in 4/26 cases. Intraoperative complications were reported in 2/23 cases, short-term complications in 17/25 cases, of which eight were major, and long-term complications in 7/18, of which two were major. Patella luxation was seen in one case and is a previously unreported complication. The overall outcome was excellent in 9/24 cases, good in 5/24 cases, fair in 7/24 cases and poor in 3/24 cases. Follow-up time ranged from 1.5 months to 9 years with the median (IQR) of 9.5 (4.0 to 28.5) months.

CONCLUSIONS

Multiligament stifle injury in dogs is associated with a high rate of major complications. The overall outcome was good to excellent in just over half of the dogs.

Surgical accuracy and clinical outcomes of image-free robotic-assisted total knee arthroplasty

BACKGROUND

The development of total knee arthroplasty (TKA) for knee osteoarthritis (OA) has a good reputation for its effectiveness in reducing joint pain and improving range of motion. We aimed to review our early results using the image-free robotic-assisted technology in knee arthroplasty.

METHODS

A total of 71 patients suffering from end-stage OA knee receiving TKA operated by robotic-assisted surgery between the years 2018 and mid-2021 were recruited. Clinical and radiological outcomes were compared with age and sex-matched control group (conventional TKA).

RESULTS

The radiological outcome showed significantly more postoperative lower limb alignment outliers in conventional side than robotic-assisted sides. Postoperative knee scores were similar among both groups. Robotic-assisted TKA required a longer implantation time but a shorter hospital stay.

CONCLUSION

Robotic-assisted TKA achieved a lower rate of mechanical axis Outlier in the coronal and sagittal plane with a shorter hospital stay. Yet both methods achieve a similar functional outcome.

Large-Scale Genetic Correlation Analysis between Spondyloarthritis and Human Blood Metabolites

The aim was to study the genetic correlation and causal relationship between spondyloarthritis (SpA) and blood metabolites based on the large-scale genome-wide association study (GWAS) summary data. The GWAS summary data (3966 SpA and 448,298 control cases) of SpA were from the UK Biobank, and the GWAS summary data (486 blood metabolites) of human blood metabolites were from a published study. First, the genetic correlation between SpA and blood metabolites was analyzed by linkage disequilibrium score (LDSC) regression. Next, we used Mendelian randomization (MR) analysis to perform access causal relationship between SpA and blood metabolites. Random effects inverse variance weighted (IVW) was the main analysis method, and the MR Egger, weighted median, simple mode, and weighted mode were supplementary methods. The MR analysis results were dominated by the random effects IVW. The Cochran's Q statistic (MR-IVW) and Rucker's Q statistic (MR Egger) were used to check heterogeneity. MR Egger and MR pleiotropy residual sum and outlier (MR-PRESSO) were used to check horizontal pleiotropy. The MR-PRESSO was also used to check outliers. The "leave-one-out" analysis was used to assess whether the MR analysis results were affected by a single SNP and thus test the robustness of the MR results. Finally, we identified seven blood metabolites that are genetically related to SpA: X-10395 (correlation coefficient = -0.546, p = 0.025), pantothenate (correlation coefficient = -0.565, p = 0.038), caprylate (correlation coefficient = -0.333, p = 0.037), pelargonate (correlation coefficient = -0.339, p = 0.047), X-11317 (correlation coefficient = -0.350, p = 0.038), X-12510 (correlation coefficient = -0.399, p = 0.034), and X-13859 (Correlation coefficient = -0.458, p = 0.015). Among them, X-10395 had a positive genetic causal relationship with SpA (p = 0.014, OR = 1.011). The blood metabolites that have genetic correlation and causal relationship with SpA found in this study provide a new idea for the study of the pathogenesis of SpA and the determination of diagnostic indicators.

Surgical accuracy and clinical outcomes of image-free robotic-assisted total knee arthroplasty

BACKGROUND

The development of total knee arthroplasty (TKA) for knee osteoarthritis (OA) has a good reputation for its effectiveness in reducing joint pain and improving range of motion. We aimed to review our early results using the image-free robotic-assisted technology in knee arthroplasty.

METHODS

A total of 71 patients suffering from end-stage OA knee receiving TKA operated by robotic-assisted surgery between the years 2018 and mid-2021 were recruited. Clinical and radiological outcomes were compared with age and sex-matched control group (conventional TKA).

RESULTS

The radiological outcome showed significantly more postoperative lower limb alignment outliers in conventional side than robotic-assisted sides. Postoperative knee scores were similar among both groups. Robotic-assisted TKA required a longer implantation time but a shorter hospital stay.

CONCLUSION

Robotic-assisted TKA achieved a lower rate of mechanical axis Outlier in the coronal and sagittal plane with a shorter hospital stay. Yet both methods achieve a similar functional outcome.

The accuracy of statistical shape models in predicting bone shape: A systematic review

BACKGROUND

This systematic review aims to ascertain how accurately 3D models can be predicted from two-dimensional (2D) imaging utilising statistical shape modelling.

METHODS

A systematic search of published literature was conducted in September 2022. All papers which assessed the accuracy of 3D models predicted from 2D imaging utilising statistical shape models and which validated the models against the ground truth were eligible.

RESULTS

2127 papers were screened and a total of 34 studies were included for final data extraction. The best overall achievable accuracy was 0.45 mm (root mean square error) and 0.16 mm (average error).

CONCLUSION

Statistical shape modelling can predict detailed 3D anatomical models from minimal 2D imaging. Future studies should report the intended application domain of the model, the level of accuracy required, the underlying demographics of subjects, and the method in which accuracy was calculated, with root mean square error recommended if appropriate.

A Standardized Physical Examination Method for Joints to Determine Rheumatoid Arthritis Activity Using the Modified RAND/UCLA Appropriateness Method

Introduction

Rheumatoid arthritis activity is evaluated based on a physical examination of each of the joints. However, the joint examination is not standardized, and the techniques are variable and difficult to reproduce due to disagreements among examiners.

Objective

To recommend standardized joint examination techniques based on the modified RAND-UCLA appropriateness method.

Methods

A review of the literature was conducted to determine the items to be included in the joint examination; subsequently, a consensus of rheumatologists was achieved with the modified RAND-UCLA methodology to issue the recommendations. The diagnosis of RA and differential diagnoses were excluded.

Results

Two hundred fifteen rheumatologists were invited to participate. Five were included in the core group and 26 in the group of clinical experts. Clinical experience ranged between 2 and 25 years (mean 15.6 years; standard deviation 6.3 years). Most rheumatologists participated in all rounds (Round 1: 100%, Round 2: 61%, and Round 3: 61%). Of the 45 statements in the questionnaire assessing the examination techniques, 28 (62%) were retained. In addition, 6 other statements were included during the face-to-face meeting for a total of 34 final statements.

Conclusion

Physical examination techniques for joints that determine RA activity are heterogeneous and differ markedly in terms of several characteristics. A list of recommendations is proposed as a guide to improve and standardize the method for the physical examination of the joints. This standardization will improve the diagnosis and results for patients with RA and help health caregivers provide better treatment.

[Forensic medical characteristic of articular injuries]

THE AIM OF THE STUDY

Is to refine the mechanism of major joints' damage formation and qualification criteria of harm degree to the health in articular injuries. The number of patients equal 246, suffered in different circumstances, were examined. Damages of skin and soft tissues in the joints region without affection of internal structures (47%), intraarticular fractures with impaired articular surface congruence (18.0%) and periarticular fractures (15.8%) were the most frequent in non-fatal injuries' outcomes in pedestrians and cyclists suffered from collisions with moving vehicles. Dead pedestrians and cyclists injured in road traffic accidents (RTA) from the side of joints structure had the most frequent the periarticular fractures (6.8%), intraarticular fractures with impaired (14.5%) or intact articular surface congruence (6.5%). Dislocations (45.9%) and dislocation-fracture (54.1%) were common in mechanical injuries. Mostly, work ability was recovered for 1.5-2.0 months in the presence of periarticular fracture, and there was no permanent loss of general work ability. The permanent loss of general work ability exceed 33.0% in case of complicated intraarticular fractures of coxofemoral structures, and in the case of a similar injury of other joints was less than this value. The period of work ability recovery in the case of intraarticular fractures was 2.5-3 months, in the presence of complicated dislocations was from 3 to 6 months. The permanent loss of general work ability did not exceed 30%. The period of work ability recovery in patients with fracture-dislocation varied from 3 to 6 months. The permanent loss of general work ability in this case was from 20% to 60%. The severity of harm to the health was classified as moderate degree in the case of uncomplicated isolated injuries of joints structures, and as moderate or severe degree in the presence of complicated isolated injuries. Bruises of joints' soft tissues were evaluated as mild bodily injury causing a health disorder. Bruises of joints' soft tissues, as well as periarticular and intraarticular fractures in pedestrians and cyclists in the case of RTA are formed when falling on the road surface. Dislocations and fractures-dislocations of humerus and forearm occur as a result of an indirect injury mechanism. Articular injuries of femur are formed under the influence of traumatic force to the femur, exceeding the capability of coxofemoral joint (an indirect injury mechanism). Dislocations and fractures-dislocations in ankle joint are occurred as a result of an indirect injury mechanism and are caused by foot's flexion or rotation with great strength.

A case of knuckle pad syndrome in a middle-aged man

Knuckle pads are benign papules, nodules, or plaques overlying joints and typically manifest at the proximal interphalangeal joints (PIPs). They may be confused with other dermatologic or rheumatologic diseases. Treatment options for primary knuckle pads are limited and acquired knuckle pads typically improve with withdrawal of the offending insult.

Effect of emicizumab prophylaxis on bone and joint health markers in people with haemophilia A without factor VIII inhibitors in the HAVEN 3 study

INTRODUCTION

Emicizumab prophylaxis significantly reduces bleeding events; however, the associated impact on bone/joint health is unknown.

AIM

To explore the effect of emicizumab prophylaxis on bone/joint health in people with haemophilia A (PwHA) without FVIII inhibitors enrolled in HAVEN 3 (NCT02847637).

METHODS

Haemophilia joint health scores (HJHS; v2.1) were evaluated at baseline and Weeks 49 and 97 in PwHA receiving emicizumab (n = 134), and at baseline and Weeks 49, 73 and 97 in PwHA who switched to emicizumab after 24 weeks of no prophylaxis (n = 17). Bone and joint biomarkers were measured in 117 PwHA at baseline and at Weeks 13, 25, 49 and 73.

RESULTS

HJHS was lower for PwHA who were previously on FVIII prophylaxis, aged <40 years or had no target joints at baseline compared with PwHA who were receiving no prophylaxis, aged ≥40 years or with target joints. Clinically significant mean (95% confidence interval) improvements from baseline of -2.13 (-3.96, -.29) in HJHS joint-specific domains were observed at Week 49 in PwHA with at least one target joint at study entry (n = 71); these changes were maintained through Week 97. Improvements in HJHS from baseline were also observed for PwHA aged 12-39 years. Biomarkers of bone resorption/formation, cartilage degradation/synthesis, and inflammation did not change significantly during emicizumab prophylaxis.

CONCLUSIONS

Clinically relevant improvements in HJHS were observed in younger PwHA and those with target joints after 48 weeks of emicizumab in HAVEN 3. Biomarkers of bone/joint health did not show significant changes during 72 weeks of emicizumab prophylaxis.

Adipokine profile on joint and periodontal conditions in first-degree relatives of patients with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by joint inflammation and destruction.

OBJECTIVE

Establish the association between Porphyromonas gingivalis (P. gingivalis) infection, body mass index (BMI), joint involvement, and serum adipokines in first-degree relatives (FDR) of patients with rheumatoid arthritis (RA).

METHODS

The cross-sectional study evaluated 124 FDR and 124 healthy controls (HC). The clinical examination included joint and radiographic evaluation and calculation of BMI. Serum adipokine levels were measured (leptin, vaspin, adiponectin, resistin, and adipsin), as were the erythrocyte sedimentation rate, C-reactive protein, and anti-citrullinated protein antibodies. Investigations were performed to detect P. gingivalis, and anti-P. gingivalis antibodies. Statistical analyses were performed to confirm associations.

RESULTS

Leptin levels in FDR were associated with BMI >25 (OR, 2.64; 95%CI, 1.17-5.97; P=0.019), radiographic damage (Simple Erosion Narrowing Score [SENS])/hands, total SENS, and joint space narrowing in feet (P=0.037, 0.026, 0.020, respectively). FDR had more tender joints (P=0.018); this finding was associated with high levels of leptin and resistin and low levels of adipsin (P=0.040, 0.040, and 0.019, respectively). The presence of P. gingivalis was related to FDR, low levels of adipsin, resistin, adiponectin, and a trend toward higher levels of leptin (P=0.002, 0.001, 0.003, and 0.060, respectively), whereas anti-P. gingivalis antibodies were related to low levels of adipsin (P=0.001).

CONCLUSION

In FDR, serum adipokine levels were associated with overweight, presence of P. gingivalis. Adipokine levels were also associated with joint involvement. Hence, adipokines may be involved in the pathogenesis of RA in FDR and warrant further investigation.

Symptomatic Joint Hypermobility Is Associated with Low Back Pain: A National Adolescents Cohort Study

Background: Low back pain (LBP) is a widespread medical complaint affecting many people worldwide and costing billions. Studies suggest a link between LBP and joint hypermobility. This study aimed to examine the association between symptomatic joint hypermobility (SJH), LBP, and gender. Methods: Data were obtained from a medical database containing 17-year-old candidates’ records before recruitment into mandatory military service. According to the Regulations of Medical Fitness Determination, information on disability codes associated with LBP and SJH was retrieved. Results: According to this national survey, the prevalence of SJH is 0.11% (1355 cases out of 1,220,073 subjects). LBP was identified in 3.7% of the cohort (44,755 subjects). Subjects were further subdivided into LBP without objective findings (LBPWF) (3.5%) and LBP with objective findings (LBPOF) (0.2%). The association between SJH and LBP was examined: the Odds Ratio (OR) was 2.912 (p < 0.0001). The odds rations for LBPWF and LBPOF were further calculated to be 2.914 (p < 0.000) and 2.876 (p < 0.000), respectively. Subjects with SJH were almost three times more prone to LBPWF and LBPOF. Conclusion: SJH is strongly associated with LBP in young adults. Further pathophysiological research is needed.

Evaluation of EDTA and nitric acid solutions for decalcification of joints in AG/WT, BALB/c, C57, DBA1/J mice, and in Wistar rats

Decalcification of mineralized samples for microscopic analysis involves competing factors including decalcification time, preservation of tissue integrity and cost. We investigated the utility of different decalcification solutions for studying joints in AG/WT, BALB/c, C57, DBA1/J mice and Wistar rats. The hind paws of the rodents were removed and fixed with 10% buffered formalin. Specimens were divided randomly into three groups for demineralization: 10% nitric acid, 12.5% EDTA at room temperature and 12.5% EDTA at 35 °C with shaking. Sections of joints were stained with hematoxylin and eosin (H & E). We evaluated decalcification time and expense, ease of cutting sections, preservation of nuclear basophilia and intranuclear detail, and intensity of eosin staining. The 10% nitric acid solution produced the most rapid decalcification for the mice, but not the rats. The 12.5% EDTA solution at 35 °C with shaking did not decrease decalcification time. Effects on microtomy were variable as were the effects on H & E staining. The EDTA solution provided the best basophilia and intranuclear detail for the mice. For rats, only 12.5% EDTA at 35 °C with shaking produced good preservation. Preservation of nuclear basophilia and intranuclear detail for rats was best with 10% nitric acid and EDTA 35 °C. For mice, 10% nitric acid failed to preserve nuclear basophilia and intranuclear detail. For intensity of eosin staining, EDTA at room temperature and EDTA 35 °C was best for both mice and rats. Sections also exhibited good H & E staining in most samples decalcified with 10% nitric acid. Although we found considerable variation among groups of animals, we found less variation among the different mouse strains than between mice and Wistar rats.

Pregnancy-related sacroiliac joint findings in females with low back pain: a four-year magnetic resonance imaging follow-up study

BACKGROUND

Pregnancy-related pain may be associated with sacroiliac joint (SIJ) changes, detectable by magnetic resonance imaging (MRI).

PURPOSE

To analyze the prevalence and course of SIJ MRI and clinical findings in women referred with low back pain and relate these to pregnancy.

MATERIAL AND METHODS

A retrospective follow-up study from a longitudinally collected cohort comprising 328 women.

RESULTS

Women reporting debut of pain in relation to a pregnancy (PP group) tended to have a higher baseline prevalence of all investigated MRI findings, cumulated positive SIJ tests, and a potential fulfilment of the spondyloarthritis diagnosis compared to remainders. The prevalence of subchondral bone marrow edema (BME), any SIJ MRI finding, and potential fulfilment of the spondyloarthritis diagnosis were significantly higher in the PP group compared to women who had not been pregnant. In the total study group, the prevalence of ≥1 MRI finding increased over the four-year study period from 34% to 47% (P<0.001), driven by increasing prevalence of BME (25% to 32%; P=0.008) and fatty marrow deposition (FMD) (20% to 25%; P=0.020). In addition, the BME volume score increased. Over time, the PP group had persisting high prevalence of buttock pain and total MRI findings and their FMD volume score increased, but there were no between-group differences in MRI variables at follow-up.

CONCLUSION

Overall, the prevalence of MRI findings increased over time. Although the PP group had different clinical and SIJ MRI characteristics cross-sectional at baseline compared to remainders, longitudinal analyses revealed that these diminished over time.

Joint status of patients with nonsevere hemophilia A

BACKGROUND

Joint bleeding in hemophilia may eventually lead to joint damage. In nonsevere hemophilia, joint bleeds occur infrequently. Currently, knowledge on the joint status of patients with nonsevere hemophilia using objective imaging is limited.

OBJECTIVE

To investigate the joint status in patients with nonsevere hemophilia A.

METHODS

This cross-sectional study included patients with nonsevere hemophilia A aged 24-55 years. Joint status was assessed by magnetic resonance imaging (MRI) of the elbows, knees, and ankles and International Prophylaxis Study Group (IPSG) scores were calculated. Lifetime joint bleeding history was collected from medical files. The contribution of factors to joint outcome was explored using multivariable linear regression analysis.

RESULTS

In total, 51 patients were included, of whom 19 (37%) had moderate and 32 (63%) had mild hemophilia. Patients had a median age of 43 years (interquartile range [IQR] 32-50), a median factor VIII activity of 10 IU/dl (IQR 4-16) and a median annual joint bleeding rate (AJBR) of 0.0 (IQR 0.0-0.2). Soft-tissue changes (IPSG subscore > 0) in the elbows, knees, and ankles were present in 19%, 71%, and 71% of patients, respectively. Osteochondral changes (IPSG subscore > 0) in the elbows, knees, and ankles were present in 0%, 20%, and 35% of patients, respectively. In 14% of bleed-free joints, hemosiderin depositions were observed. Age and AJBRs were most strongly associated with the IPSG score.

CONCLUSION

This study demonstrates that a substantial proportion of adults with nonsevere hemophilia has joint changes on MRI despite low joint bleeding rates.

Advances and Challenges in Paleobiological Reconstructions of Joint Mobility

Paleobiological reconstructions of joint mobility are an essential component of functional analyses of extinct animals. Over the past half-decade, the methods underlying mobility studies have advanced rapidly in three main areas: increasing complexity of virtual joint manipulation, formalizing pose viability criteria, and constructing more rigorous quantitative frameworks. Here we contextualize and review the recent history of this field, and call attention to remaining challenges and potential future directions. Additionally, we make available and describe a set of user-friendly scripts for the animation software Autodesk Maya. In doing so, we aim to make many of the latest approaches for virtual mobility reconstruction more easily accessible to other researchers, encouraging their broader adoption and collaborative improvement.

Atypical Properties of a Thin Silver Layer Deposited on a Composite Textile Substrate

Thin layers are widely used in electronics and protective coatings. They are also increasingly used in wearable electronics. A major challenge affecting the use of thin layers is their connection to flexible substrates, particularly textile products. This article describes the stability of the resistance of a silver layer with a thickness of 250 nm in a wide temperature range of 15–295 K. The aim was to determine the temperature dependence of the resistance of layers formed on a composite textile substrate compared with that of layers produced on an Al₂O₃ substrate. The results showed that the electrical parameters of the layer formed on the composite textile substrate changed in a manner atypical for metallic layers. This may have been due to the polyurethane base layer. The roughness and ability to deform under the influence of heat of the substrate can significantly affect the electrical parameters of a thin metal layer produced by the PVD coating process, which is important for the design of textronic applications.

Musculoskeletal Manifestations of Sarcoidosis

Since its initial description in the late 19th century, sarcoidosis has been extensively studied. Although the general mechanism of immune activation is known, many details especially in the context of disease associations are still missing. One of such associations is the musculoskeletal complications that are widely variable in terms of presentation and response to treatment. Sarcoidosis can involve the joints leading to acute and, less commonly chronic, arthritis. While acute arthritis is mostly self-resolving in nature, chronic arthritis may lead to deformity and destruction of the joint. Sarcoidosis can also involve the muscles, leading to different pathologies primarily categorized according to the clinical presentation, despite the efforts to find a new classification based on imaging, histological, and clinical findings. The bones can be directly and indirectly affected. Different types of bone lesions have been described, although around half of these patients remain asymptomatic. Osteoporosis, increased risk of fractures, hypercalcemia, and hypercalciuria are examples of the indirect effect of sarcoidosis on the bones, possibly contributed to elevated levels of calcitriol. Nevertheless, sarcoidosis can be associated with small-vessel, medium-vessel, and large vessel vasculitis, although it is frequently difficult to differentiate between the co-existence of a pure vasculitis and sarcoidosis and sarcoid vasculitis.

Magnetic Resonance Imaging Versus Computed Tomography for Three-Dimensional Bone Imaging of Musculoskeletal Pathologies: A Review

Magnetic resonance imaging (MRI) is increasingly utilized as a radiation‐free alternative to computed tomography (CT) for the diagnosis and treatment planning of musculoskeletal pathologies. MR imaging of hard tissues such as cortical bone remains challenging due to their low proton density and short transverse relaxation times, rendering bone tissues as nonspecific low signal structures on MR images obtained from most sequences. Developments in MR image acquisition and post‐processing have opened the path for enhanced MR‐based bone visualization aiming to provide a CT‐like contrast and, as such, ease clinical interpretation. The purpose of this review is to provide an overview of studies comparing MR and CT imaging for diagnostic and treatment planning purposes in orthopedic care, with a special focus on selective bone visualization, bone segmentation, and three‐dimensional (3D) modeling. This review discusses conventional gradient‐echo derived techniques as well as dedicated short echo time acquisition techniques and post‐processing techniques, including the generation of synthetic CT, in the context of 3D and specific bone visualization. Based on the reviewed literature, it may be concluded that the recent developments in MRI‐based bone visualization are promising. MRI alone provides valuable information on both bone and soft tissues for a broad range of applications including diagnostics, 3D modeling, and treatment planning in multiple anatomical regions, including the skull, spine, shoulder, pelvis, and long bones.

Morphological Features of the Coccyx in the Turkish Population and Interrelationships Among the Parameters: A Computerized Tomography-Based Analysis

Introduction

The coccyx is well-known to be a highly variable structure considering its morphology. To our knowledge, the relationship between the coccygeal types and other morphological features has not been studied yet. In addition to the interrelations among morphological parameters, this study investigated the morphology and morphometry of coccyx more extensively in the adult Turkish population using computerized tomography images.

Methods

Five hundred subjects who underwent pelvic computerized tomography were included in this study. In addition to coccyx type and the counts of coccygeal vertebrae and segments, the presence of coccygeal deviation, sacrococcygeal joint (SCJ) fusion, SCJ subluxation, intercoccygeal joint (ICJ) fusion, and coccygeal spicule were evaluated. The coccygeal length, sacrococcygeal angle, and intercoccygeal angle were measured on the digital workstation. The findings were subjected to statistical analyses.

Results

The coccygeal vertebra count ranged between three to five, with an average of 4.04 ± 0.48. The range of coccygeal segment count was between one and five, with an average of 2.53 ± 1.02. ICJ fusion in any segment, SCJ fusion, and SCJ subluxation were identified in 397 subjects (79.4%), 343 subjects (68.6%), and 17 subjects (3.4%), respectively. The coccyx types from the most common to the least common were as follows: type 2, type 1, type 3, type 4, and type 5. Coccygeal deviation to the left side was observed in 71 subjects (14.2%), while coccygeal deviation to the right side was observed in 61 subjects (12.2%). A coccygeal spicule was identified in 73 subjects (14.6%). The subjects’ mean age demonstrated no significant difference considering the ICJ fusion (p=0.271), SCJ subluxation (p=0.51), coccygeal spicule (p=0.337), features of coccygeal deviation (p=0.83), and coccyx types (p=0.11). The subjects with SCJ fusion (50.7 ± 18.3 years) were significantly older than the subjects without SCJ fusion (46.5 ± 18.5 years) (p=0.016). The differences between the coccyx types considering the rate of SCJ fusion (p=0.002), ICJ fusion (p=0.04), and spicule presence (p<0.001) as well as the coccygeal vertebra count (p<0.001) were significant.

Conclusion

The presence of coccygeal spicule, a risk factor for coccydynia, is reported to be 14.6% in this study group that represents the Turkish population. This study indicates an association between the coccyx types and the frequency of SCJ fusion, ICJ fusion, and spicule presence and consequently suggests the significance of the coccyx type among the morphological features to cause susceptibility to coccydynia. Due to the multiplicity of the pain generators in the coccygeal region that is established by previous reports, the comparisons of different human populations and the knowledge on the interrelations between the morphologic parameters might facilitate the comprehension of the etiology of coccydynia. The clarification of interrelationship existence among the coccygeal morphological parameters requires further investigations.

Clinico-Epidemiological Profile and Outcome of Children with IgA Vasculitis in Aseer Region, Southwestern Saudi Arabia

Introduction: Immunoglobulin A (IgA) vasculitis is one of the most common forms of primary vasculitis in children; it typically has a benign course but can be aggressive and require intervention. Aim of the work: The aim of this retrospective study was to evaluate the epidemiological and clinical profile and treatment modalities used for children with IgA vasculitis in the southwestern region of Saudi Arabia. Material and Methods: We reviewed the medical records of 89 children admitted to Abha Maternity and Children Hospital in the southwestern region of Saudi Arabia from January 2016 to December 2020 with a confirmed diagnosis of IgA vasculitis according to the European League Against Rheumatism/Paediatric Rheumatology International Trials Organisation/Pediatric Rheumatology European Society criteria. Results: Eighty-nine children had a confirmed diagnosis of IgA vasculitis, with 50 boys (56.2%) and 39 girls (43.8%; male-to-female ratio of 1.28:1) and a mean age at diagnosis of 5.87 ± 2.81 years. The mean hospital stay duration was 5.66 ± 4.72 days. Infections preceded 29.2% of the cases, with upper respiratory tract infections comprising 24.7%. Approximately 31.5% of the cases were diagnosed in summer, followed by autumn in 28% of the cases. Rash was present in 100%, arthritis in 72.2%, gastrointestinal tract involvement in 60.7%, and renal involvement in 23.5% of cases. Thrombocytosis and leukocytosis were found in 35% and 46% of all cases, and 52.3% and 47.6.25% of cases with renal involvement, respectively (OR = 2.035, 95% CI: 0.75–5.52 and OR = 1.393, 95% CI: 0.522–1.716, respectively). Approximately 26% of cases experienced relapses. Treatment was conservative in 23.6%, oral prednisolone in 23.6%, and pulse steroid in 45% of cases. Abdominal pain with lower gastrointestinal tract bleeding was the primary indication for initiating pulse steroid treatment. Conclusions: There were similarities and differences in the epidemiology and frequency of clinical manifestations of patients with IgA vasculitis compared to previous studies. Children presenting with such epidemiological and clinical profile need to be closely monitored and long-term follow-up is recommended to improve the outcomes.

Infrared Thermography for the Evaluation of Inflammatory and Degenerative Joint Diseases: A Systematic Review

OBJECTIVE

Inflammation plays a central role in the pathophysiology of rheumatic diseases as well as in osteoarthritis. Temperature, which can be quantified using infrared thermography, provides information about the inflammatory component of joint diseases. This systematic review aims at assessing infrared thermography potential and limitations in these pathologies.

DESIGN

A systematic review was performed on 3 major databases: PubMed, Cochrane library, and Web of Science, on clinical reports of any level of evidence in English language, published from 1990 to May 2021, with infrared thermography used for diagnosis of osteoarthritis and rheumatic diseases, monitoring disease progression, or response to treatment. Relevant data were extracted, collected in a database, and analyzed for the purpose of this systematic review.

RESULTS

Of 718 screened articles 32 were found to be eligible for inclusion, for a total of 2094 patients. Nine studies reported the application to osteoarthritis, 21 to rheumatic diseases, 2 on both. The publication trend showed an increasing interest in the last decade. Seven studies investigated the correlation of temperature changes with osteoarthritis, 16 with rheumatic diseases, and 2 with both, whereas 2 focused on the pre-post evaluation to investigate treatment results in patients with osteoarthritis and 5 in patients with rheumatic diseases. A correlation was shown between thermal findings and disease presence and stage, as well as the clinical assessment of disease activity and response to treatment, supporting infrared thermography role in the study and management of rheumatic diseases and osteoarthritis.

CONCLUSIONS

The systematic literature review showed an increasing interest in this technology, with several applications in different joints affected by inflammatory and degenerative pathologies. Infrared thermography proved to be a simple, accurate, noninvasive, and radiation-free method, which could be used in addition to the currently available tools for screening, diagnosis, monitoring of disease progression, and response to medical treatment.

Periarticular plasma cell tumors in cats

This report describes periarticular plasma cell tumors with abundant amyloid in 11 cats. The tarsus was the most commonly affected joint (10/11), and the masses were often circumferential around the tarsal joint, involving the dermis and subcutis. The 2 cases in which synovium was examined had neoplastic cells expanding the synovium. Three of the 5 cases staged radiographically had bony lysis of the affected joint. Cutaneous biopsy specimens often consisted of more amyloid than plasma cells, making the diagnosis difficult on small samples. Follow-up information was available in 7 cases; in those cases, the median survival was 194 days (range 53-671 days). Four cases had confirmed metastases, most often to regional lymph nodes, liver, and spleen. Although canine cutaneous plasma cell tumors are typically benign, those with abundant amyloid surrounding the joints of cats may involve deeper tissues and have a more aggressive behavior. These tumors can be difficult to diagnose due to low cellularity and abundant amyloid.

Seismic Behavior of Stone Masonry Joints with ECC as a Filling Material

This paper investigates the seismic behavior of novel stone masonry joints using ductile engineered cementitious composite (ECC) as a substitute for ordinary mortar. Ten stone masonry joints with different types of mortar/ECC were tested under axial and cyclic loads. The filling materials of mortar joints tested included ordinary mortar, polymer mortar, ECC, and composite mortar with two combination proportions of ECC and ordinary mortar. The test results indicated that ECC specimens exhibited a more stable hysteretic response as well as an improvement in strength, deformation, energy dissipation, and strength degradation. The ECC mortar joints maintained integrity during the entire loading process due to the "self-confinement" effect of ECC. A partial substitution of mortar with ECC could provide effective reinforcement and confinement to prevent mortar failure and peeling, thereby allowing such specimens to approach the seismic performance of ECC specimens. Based on the trend of shear strength variations, a corresponding failure process is defined for ECC/mortar joints under cyclic and axial compressive loads, including four distinct stages: linear elastic, crack-developing stage, interface debonding, and friction sliding. New equations are proposed for predicting the shear strength and residual shear strength of the ECC/mortar joints on the basis of the test results, which are validated in the composite mortar specimens.