Differential effects of bleeds on the development of arthropathy - basic and applied issues

What is the rationale for mesenchymal stromal cells based therapies in the management of hemophilic arthropathies?

Hemophilia A and B are rare X-linked genetic bleeding disorders due to a complete or partial deficiency in the coagulation factors VIII or IX, respectively. The main treatment for hemophilia is prophylactic and based on coagulation factor replacement therapies. These treatments have significantly reduced bleeding and improved the patients' quality of life. Nevertheless, repeated joint bleedings (hemarthroses), even subclinical hemarthroses, can lead to hemophilic arthropathy (HA). This disabling condition is characterized by chronic pain due to synovial inflammation, cartilage and bone destruction requiring ultimately joint replacement. HA resembles to rheumatoid arthritis because of synovitis but HA is considered as having similarities with osteoarthritis as illustrated by the migration of immune cells, production of inflammatory cytokines, synovial hypertrophy and cartilage damage. Various drugs have been evaluated for the management of HA with limited success. The objective of the review is to discuss new therapeutic approaches with a special focus on the studies that have investigated the potential of using mesenchymal stromal cells (MSCs) in the management of HA. A systematic review of the literature has been made. Most of the studies have focused on the interest of MSCs for the delivery of missing factors VIII or IX but in some studies, more insight on the effect of MSC injection on synovial inflammation or cartilage structure were provided and put in perspective for possible clinical applications.

Physical activity and factor VIII levels in patients with haemophilia: A real-world prospective observational study

INTRODUCTION

Regular physical activity (PA) is recommended for patients with haemophilia (PwH). For PwH it is crucial to ensure a sufficient factor level to prevent PA-induced bleedings. However, there is a gap in the literature dealing with specific factor levels, which are needed when performing specific types of PA.

AIM

To provide data on factor VIII (FVIII) levels at the start of PA performed by PwH.

METHODS

In this prospective 12-month real-world observational study, 23 PwH recorded every PA they performed and the FVIII levels at the start of the PA using a pharmacokinetic application. PA types were clustered according to the collision and injury risk into three categories (Cat I = low, Cat II = medium, Cat III = high risk). Haemophilia Joint Health Scores (HJHS) were performed at baseline, after 6 and 12 months.

RESULTS

795 PA sessions of Cat I, 193 of Cat II, and 23 of Cat III were documented. FVIII levels at the start of PA were different between categories (Cat I: 29.8 ± 32.1%, Cat II: 38.3 ± 33.4%, Cat III: 86.6 ± 29.2%). Out of all PA sessions, 145 (14%) were performed at a factor level of ≤3%. Three PA-induced bleeding occurred. Baseline HJHS was 14.5 ± 13.6 points and did not change throughout the study.

CONCLUSION

This study provides real-life data on FVIII levels at the start of 1011 PA sessions. PwH are mainly active in low-risk sports with higher FVIII levels observed in Cat II and III, respectively. Only three PA-induced bleeding occurred, even though several PA were started with low FVIII levels.

Towards Personalized Treatment in Haemophilia: The Role of Genetic Factors in Iron and Heme Control to Identify Patients at Risk for Haemophilic Arthropathy

The treatment landscape for haemophilia is changing rapidly, creating opportunities for personalized treatment. As major morbidity is still caused by haemophilic arthropathy, understanding the factors affecting joint damage and joint damage progression might lead to more individualized treatment regimens. We investigated the association of HFE mutations or HMOX1 polymorphisms affecting iron/heme handling with radiographic joint damage in 252 haemophilia patients (severe and moderate). Although iron levels and transferrin saturation were significantly increased in the 95 patients with an HFE mutation, neither carrying this mutation nor the HMOX1 polymorphism was associated with radiographic joint damage, and the same was true after adjustment for well-known factors associated with arthropathy. In conclusion, this study does not support the hypothesis that HFE mutations or HMOX1 polymorphisms can be used to predict the development of haemophilic arthropathy.

Subclinical synovial proliferation in patients with severe haemophilia A: The value of ultrasound screening and biochemical markers

AIM

Subclinical bleeding and inflammation play a role in progression of haemophilic arthropathy. Synovial proliferation is predictive of joint bleeding and its early detection may guide treatment changes and prevent arthropathy progression. This study evaluated the prevalence of active and inactive subclinical synovial proliferation and investigated potential biochemical blood/urine markers to identify patients with active subclinical synovial proliferation.

METHODS

This cross-sectional study included patients with severe haemophilia A born 1970-2006 who were evaluated during routine clinic visits. Patients with (a history of) inhibitors or recent joint bleeding were excluded. Elbows, knees and ankles were examined for subclinical synovial proliferation by ultrasound and physical examination. Active synovial proliferation was distinguished from inactive synovial proliferation using predefined criteria. Blood/urine biochemical markers (serum osteopontin, sVCAM-1, Coll2-1, COMP, CS846, TIMP, and urinary CTX-II) were compared individually and as combined indexes between patients with and without active synovial proliferation.

RESULTS

This cohort consisted of 79 patients with a median age of 31 years (range 16.5-50.8 years) with 62/79 (78%) of the patients using continuous prophylaxis. The annualized joint bleeding rate over the last 5 years was .6 (.2-1.1). Active (17/79, 22%) and inactive subclinical synovial proliferation (17/79, 22%) were both prevalent in this cohort. Biochemical markers were not correlated with active subclinical synovial proliferation.

CONCLUSION

Subclinical synovial proliferation, both active and inactive, was prevalent in patients with severe haemophilia A with access to prophylaxis and would be overlooked without routinely performed ultrasounds. Biochemical markers were unable to identify patients with active subclinical synovial proliferation.

Targeted delivery of miR125a-5p and human Factor VIII attenuates molecular mediators of hemophilic arthropathy

Hemophilic arthropathy (HA) due to repeated bleeding into the joint cavity is a major cause of morbidity in patients with hemophilia. The molecular mechanisms contributing to this condition are not well characterized. MicroRNAs (miRs) are known to modulate the phenotype of multiple joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA). Since miR125a is known to modulate disease progression in OA and RA, we performed a targeted screen of miR125a-5p and its target genes in a murine model of chronic HA. A digital PCR analysis demonstrated significant downregulation of miR125a-5p (2-fold vs control joint). Further molecular evaluation revealed elevated expression of the immunological markers STAT1 (7.6-fold vs control joint) and TRAF6 (10.6 fold vs control joint), which are direct targets of miR125a-5p. We then studied the impact of targeted overexpression of miR125a-5p using an Adeno-associated virus (AAV) vector in modulating the molecular mediators of HA. AAV5-miR125a vectors were administered intra-articularly either alone or in combination with a low dose of AAV8-based human factor 8 (F8) gene in a murine model of HA. We observed significantly increased expression of miR125a-5p in AAV5-miR125a administered mice (~12 fold vs injured joint) or in combination with AAV8-F8 vectors (~44 fold vs injured joint). The activity assay revealed ~17 %-20 % FVIII levels in mice that received low dose liver-directed F8 gene therapy. Further immunohistochemical analysis, demonstrated a decrease in inflammatory markers (STAT1 and TRAF6) and cartilage-degrading matrix metalloproteinases (MMPs) 3, 9, 13 in the joints of treated animals. These data highlight the crucial role of miR125a-5p in the development of HA.

Pre-operative synovial hyperaemia in haemophilia patients undergoing total knee replacement and the effects of genicular artery embolization: A retrospective cohort study

AIM

Haemophilia is characterized by recurrent joint bleeding caused by a lack of clotting factor VIII or IX. Due to repeated joint bleeding, end-stage arthropathy occurs in relatively young patients. A total knee replacement (TKR) can be a solution. However, TKR may be complicated by perioperative and postoperative bleeds despite clotting factor therapy. The aim of this study was to evaluate the prevalence of pre-operative synovial hyperaemia and the effects of Genicular Artery Embolization on synovial hyperaemia and 3-month postoperative joint bleeding.

METHODS

In this retrospective cohort study, all patients with haemophilia who underwent periarticular catheter angiography between 2009 and 2020 were evaluated after written informed consent. Synovial hyperaemia on angiography was scored by an interventional radiologist.

RESULTS

Thirty-three angiography procedures in 24 patients were evaluated. Median age was 54.4 years (IQR 48.4-65.9). Preoperative synovial hyperaemia was observed in 21/33 joints (64%). Moderate and severe synovial hyperaemia was observed in 10/33 joints (30%). Synovial hyperaemia decreased in 13/15 (87%) joints after embolization. Three-month postoperative joint bleeding occurred in 5/32 joints: in 2/18 joints (11%) without synovial hyperaemia and in 3/14 joints (21%) with mild synovial hypertrophy. Non-embolized and embolized joints did not differ regarding 3-month postoperative bleeding (P = .425). No complications were observed after embolization.

CONCLUSION

One-third of patients with haemophilia requiring a TKR had moderate or severe synovial hyperaemia which can be reduced safely by Genicular Artery Embolization prior to TKR. Three-month postoperative bleeding appears to occur independently of the presence of residual mild synovial hyperaemia.

Synovitis in hemophilia: preventing, detecting, and treating joint bleeds

INTRODUCTION

Most bleeding events in individuals with hemophilia occur within the ankle, knee, and elbow joints. Should the bleeding persist, the synovial membrane starts to hypertrophy and a vicious cycle of chronic hemophilic synovitis (CHS) occurs, leading to joint destruction.

AREAS COVERED

This article covers the prompt diagnosis of CHS by point-of-care ultrasonography (POC-US) and its treatment by means of several types of synovectomy.

EXPERT OPINION

It is essential to prevent, detect and treat hemophilic synovitis, because it indicates that the joint has bled and is at risk of bleeding further. Prophylaxis with standard half life (SHL) factor VIII (FVIII) concentrate is the standard of care for individuals with severe hemophilia A and can also be considered for selected patients with moderate disease. Several years of real-world experience with extended half life (EHL) FVIII, emicizumab, and other drugs in development will be needed to ascertain their final effect on bleeding and its complications. We must look for synovitis in individuals declaring joint pain and in asymptomatic patients, and POC-US is the most reasonable imaging instrument with which to carry out periodic joint screening. Radiosynovectomy, chemical synovectomy, and arthroscopic synovectomy markedly reduce bleeding events.

Synovitis and joint health in patients with haemophilia: Statements from a European e-Delphi consensus study

INTRODUCTION

Synovitis, a common feature in haemophilia, is triggered by the presence of blood in joints, and represents the first step towards the development of chronic arthropathy. Synovitis may be detected early by means of ultrasound or magnetic resonance imaging scan; clinical joint scores are less sensitive in this setting. Regular long-term prophylaxis with clotting factor concentrates, as primary prophylaxis and tailored to individual needs, has high efficacy in preventing synovitis. In general, higher factor levels lower bleeding risk, but no direct correlation between factor levels and synovitis incidence has been demonstrated.

AIM

This study aimed to develop an expert consensus relating to the definition, pathophysiology, diagnosis, prevention, follow-up and treatment of synovitis, recognising its relevance for joint health and taking into account existing knowledge gaps.

METHODS

A Delphi consensus study was designed and performed. An expert group prepared 22 statements based on existing literature; a wider expert panel subsequently voted on these.

RESULTS

Retention of panellists was high. Four statements required amending and consensus on all statements was achieved after three rounds of voting.

CONCLUSION

This e-Delphi consensus study addressed the importance of synovitis in joint health of people with haemophilia and highlighted knowledge gaps in this field. Studies on the natural course of synovitis are lacking and the biological mechanisms underlying this process are not yet fully elucidated. While basic and clinical research proceeds in this field, expert consensus can help guide clinicians in their routine clinical practice, and Delphi methodology is often used to produce best-practice guidelines.

Effectiveness of myofascial therapy on hemophilic arthropathy: A systematic review and meta-analysis of clinical trials

Background

Recurrent hemarthrosis is one of the major complications affecting joint functions, and causing chronic pain in hemophilia patients.

Objective

To summarize the existing evidence of the effects of myofascial therapy (MFT) on joint status, joint pain, and hemarthrosis in hemophilic arthropathy.

Methods

This systematic review and meta-analysis was done according to PRISMA checklist. Finally, four clinical trials included and were pooled using STATA 13. Standardized mean difference (SMD) considered as the effect size.

Results

All patients in the case group received 3 interventions of MFT over a 3-week period and were evaluated for 1-5 months. Joint pain with and without load was significantly decreased after three weeks in the intervention group compared to controls (SMD: -0.61, 95% CI: -1.02, -0.21 and 0.58, 95% CI: -0.88, -0.28 respectively). Also, joint status significantly improved three weeks later in patients with MFT compared to controls. (SMD: -0.49, 95% CI: -0.79, -0.19) and this improvement remained until the end of the follow-up period (SMD: -0.54, 95% CI: -0.84, -0.24).

Conclusion

This meta-analysis showed that MFT can be an effective intervention improving the joint status and decreasing pain perception in patients with hemophilic arthropathy. Consequently, it can play an important role in achieving higher functionality and quality of life in these patients. However, due to the small number of studies and other limitations, further well-designed trials and updated meta-analysis are needed for more accurate results and interpretation.

The value of radiosynoviorthesis for treatment of chronic synovitis in hemophilic joint disease

Chronic synovitis is contributing to the development of arthropathy in hemophilia A and B. In most patients with severe and moderate hemophilia, during lifetime, joint damage progresses despite early prophylaxis and intense treatment with coagulation factor concentrates. Recurrent hemorrhages into the joints and subclinical bleeding lead to chronic inflammation of the synovium, neoangiogenesis and remodeling, sustaining a vicious circle of bleeding-remodeling-bleeding and progression of osteochondral damage. Imaging techniques including ultrasound and MRI are able to early visualize synovitis and osteochondral changes. Early detection and sustained therapy of synovitis are important preconditions to prevent further deterioration of joint status. Chronic synovitis requires intensified substitution of coagulation factors and concomitant analgetic, antiphlogistic and physical therapy. The value of early radiosynoviorthesis (RSO) as effective method to control ongoing synovitis is discussed here. RSO is recommended as first choice therapy in case of persistant chronic synovitis, recorded in both national and international guidelines.

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.

Most subjectively affected joints in patients with haemophilia - what has changed after 20 years in Germany?

BACKGROUND

In patients with haemophilia (PwH), most frequently affected joints are the ankle, knee and elbow. Due to improved factor therapy in the last decades, these previous findings have to be verified in Germany.

AIM

The aim of this study is to detect the most affected joint, evaluate the significance of the source of pain and determine the point prevalence of back pain in Germany today.

PATIENTS AND METHODS

In a retrospective study, data of n = 300 patients with severe moderate and mild haemophilia were evaluated regarding the most affected joint, the most common source of pain, and the point prevalence of back pain. An anamnesis questionnaire and the German Pain Questionnaire were used for this assessment.

RESULTS

The most affected joint in German PwH is still the ankle (41%), followed by the knee (27%) and the elbow (11%). The most common source of pain is also the ankle joint (32%). Back pain was also identified as one of the most common sources of pain, which is comparable to the elbow (elbow:15%; back:13%). The point prevalence in PwH for back pain was significantly higher compared to the general German population (P = .031).

CONCLUSION

Our data showed that the ankle is still the most affected joint and the most common source of pain in Germany. These results also showed the relevance of back pain as a pain source. The evaluations also demonstrated the high point prevalence of back pain in PwH. Future therapies should also focus on the spine because joint changes affect posture.

Peak pressure during gait in patients with severe haemophilia: A controlled cross-sectional study

BACKGROUND

Patients with severe haemophilia suffer from bleeding-related joint changes in which the ankle joint is most frequently affected. In the resulting gait changes, the forefoot is involved by reducing the foot pressure. However, it is unclear which changes in foot pressure are present in the individual's foot zones.

RESEARCH QUESTION

The aim of the study was to determine whether compensation mechanisms are present in the foot zones regarding the peak pressure under dynamic conditions and to identify possible underlying mechanisms for gait changes.

METHODS

In a controlled cross-sectional study, a pedobarography was performed during gait with a standardized speed (3 km/h) in patients with haemophilia (PwH;n = 40) and healthy controls (Con;n = 40). Pressure pain thresholds (PPT) were detected, and Haemophilia Joint Health Score (HJHS) was performed to determine the current joint status.

RESULTS

PwH showed a decreased peak pressure in metatarsals II-IV and heel compared to Con. Patients with major-affected ankle joints (determined with the HJHS) showed a decreased single-step length, stride-length and stride-time. Accordingly, the cadence was increased by 10 ± 11 steps/min in PwH compared to Con. Furthermore, PwH showed decreased ankle range of motion (ROM) in HJHS and an altered pain perception due to reduced PPT.

SIGNIFICANCE

PwH showed a changed gait pattern in peak pressure compared to Con. A restricted rolling behavior, which might be caused by movement restrictions and pain sensation, leads to reduced pressure in the center forefoot, resulting in a shorter stride-length. Future therapies should focus on maintaining joint mobility for better rolling behavior and improving ankle joints' stability to achieve a balanced load between the midfoot, heel, and forefoot. The use of insoles adapted to our data, based on group differences between PwH and Con, could be supportive in this case.

Changes of static and dynamic spine alignment in patients with severe haemophilia

INTRODUCTION

Haemophilic arthropathy results in a restricted range of motion and pain that often affects gait. The effect of these gait changes on spinal posture has not been studied.

AIM

To evaluate whether the altered joint situation in patients with haemophilia (PwH) leads to compensatory mechanisms evident in the trunk and spine, considering static and dynamic conditions.

METHODS

PwH and healthy controls (20-65 years) were examined using rasterstereography in a controlled cohort study. Analysis was performed in static and dynamic conditions in regard to gait phases. Joint status was determined using the Haemophilia Joint Health Score (HJHS).

RESULTS

Static measurements showed no group differences in PwH (n = 40) compared to healthy controls (n = 40) except pelvic torsion (median [25%-quartile;75%-quartile]: -1.9[-3.2;.9]° vs. .5[-1.1;1.9]°; P = .007). In contrast, under dynamic conditions PwH showed significantly higher trunk inclination and lower apex lumbar lordosis in all gait phases. Additionally, pelvic torsion was increased in mid stance and terminal swing. Considering joint status, PwH had a higher global HJHS (23.5[13.0;30.0] vs. 3.0[1.0;5.0]; P<.001). A significant moderate correlation was shown between the HJHS mobility score and spine parameters (r = .228-.588; P<.05).

CONCLUSION

Degenerative joint changes in PwH lead to altered spine posture during gait. A reason could be the reduced mobility in the affected joint. Changes in spinal and pelvic posture lead to higher structural burdens; therefore, clinicians should focus on posture of spinal column during gait in daily treatment.

Haemophilia

Haemophilia A and B are rare congenital, recessive X-linked disorders caused by lack or deficiency of clotting factor VIII (FVIII) or IX (FIX), respectively. The severity of the disease depends on the reduction of levels of FVIII or FIX, which are determined by the type of the causative mutation in the genes encoding the factors (F8 and F9, respectively). The hallmark clinical characteristic, especially in untreated severe forms, is bleeding (spontaneous or after trauma) into major joints such as ankles, knees and elbows, which can result in the development of arthropathy. Intracranial bleeds and bleeds into internal organs may be life-threatening. The median life expectancy was ~30 years until the 1960s, but improved understanding of the disorder and development of efficacious therapy based on prophylactic replacement of the missing factor has caused a paradigm shift, and today individuals with haemophilia can look forward to a virtually normal life expectancy and quality of life. Nevertheless, the potential development of inhibitory antibodies to infused factor is still a major hurdle to overcome in a substantial proportion of patients. Finally, gene therapy for both types of haemophilia has progressed remarkably and could soon become a reality.

Effects of myofascial release on frequency of joint bleedings, joint status, and joint pain in patients with hemophilic elbow arthropathy: A randomized, single-blind clinical trial

BACKGROUND

Chronic joint injury of the elbow joint is common in patients with hemophilia. Myofascial release is used for the management of pain and functionality in patients with chronic restrictions.

OBJECTIVE

To evaluate the effectiveness of myofascial release in patients with hemophilic elbow arthropathy.

METHODS

Sixty-nine patients with hemophilia took part in this randomized controlled trial. They were recruited from 10 hemophilia patient Associations. They were randomly allocated to experimental (n = 35) or control group (n = 34). The intervention consisted of three 50-min sessions of fascial therapy over a 3-week period. The intervention included 11 bilaterally administered maneuvers in both upper limbs (from shoulder girdle to forearm). The study variables were frequency of elbow bleeding (self-report), joint status (Hemophilia Joint Health Score), and joint pain (visual analog scale) at baseline, after the intervention, and at the 3-month follow-up.

RESULTS

There were significant changes (P < .001) in the repeated measures factor in the frequency of hemarthrosis (F = 20.64), joint status (F = 31.45), and perceived joint pain (F = 30.08). We found group interaction with the (P < .001) in the frequency of hemarthrosis (F = 21.57), joint status (F = 99.98), and perceived joint pain (F = 44.26). There were changes (P < .01) in the pairwise comparison analysis between the pretreatment assessment and the posttreatment and follow-up assessments.

CONCLUSIONS

Myofascial release decreases frequency of elbow bleedings, and improved joint status and perception of elbow pain in patients with hemophilic elbow arthropathy. Myofascial release may be recommended to improve joint status and joint pain in patients with hemophilic elbow arthropathy.

Biochemical marker research in hemophilic arthropathy: A systematic review

Hemophilic arthropathy (HA) causes major morbidity. Breakthrough therapies reduce the bleeding frequency tremendously, but well-defined joint outcome assessments with a focus on early changes and subclinical damage are lacking. Biomarkers reflecting joint tissue turnover/inflammation might be useful to predict invalidating arthropathy. This systematic review summarized and categorized publications on blood/urinary biomarkers in HA to provide leads for implementation. A PubMed/EMBASE search was performed on September 9, 2019. All publications were assessed and allocated to one or several BIPED-categories, based on the utility of biomarkers. Of the initial 1307 publications found, 27 were eligible for inclusion. The majority (81%, n = 32/42) was cross-sectional in design, including relatively small numbers of patients (median 44, interquartile range 35-78). Fourteen percent (n = 6/42) investigated dynamic changes around a bleeding or treatment. Only two studies investigated the prognostic value of biomarkers. Most promising biomarkers were serum Coll2-1, COL-18N, COMP, C1,2C, C2M, CS846, MIF, plasma sVCAM-1 and urinary CTX-II. Comparing performances and pooling data was not possible due to heterogeneity. Currently, biomarker research in HA is still in an explorative stage and not yet sufficient for translation into daily practice. Clearly, larger homogeneous longitudinal studies in well-defined populations should be performed for further development.

Unique inflammatory signature in haemophilic arthropathy: miRNA changes due to interaction between blood and fibroblast-like synoviocytes

In haemophilia, the recurrence of hemarthrosis leads to irreversible arthropathy termed haemophilic arthropathy (HA). However, HA is a unique form of arthropathy in which resident cells, such as fibroblast‐like synoviocytes (FLS), come into direct contact with blood. Therefore, we hypothesized that FLS in HA could have a unique inflammatory signature as a consequence of their contact with blood. We demonstrated with ELISA and ELISPOT analyses that HA‐FLS expressed a unique profile of cytokine secretion, which differed from that of non‐HA‐FLS, mainly consisting of cytokines involved in innate immunity. We showed that unstable cytokine mRNAs were involved in this process, especially through miRNA complexes as confirmed by DICER silencing. A miRNOME analysis revealed that 30 miRNAs were expressed differently between HA and non‐HA‐FLS, with most miRNAs involved in inflammatory control pathways or described in certain inflammatory diseases, such as rheumatoid arthritis or lupus. Analysis of transcriptomic networks, impacted by these miRNAs, revealed that protein processes and inflammatory pathways were particularly targeted in LPS‐induced FLS, and in particular vascularization and osteoarticular modulation pathways in steady‐state FLS. Our study demonstrates that the presence of blood in contact with FLS may induce durable miRNA changes that likely participate in HA pathophysiology.

Safety and Effectiveness of Progressive Moderate-to-Vigorous Intensity Elastic Resistance Training on Physical Function and Pain in People With Hemophilia

OBJECTIVE

Strength training is recommended for people with hemophilia; however, published data are anecdotal and have methodological limitations. The purpose of this study was to evaluate the safety and effectiveness of progressive moderate-to-vigorous intensity elastic resistance training on physical function and pain in this patient population.

METHODS

A randomized controlled trial was conducted in a university laboratory setting where 20 patients (17 with severe, 1 with moderate, and 2 with mild hemophilia) aged 21 to 53 years received evaluations at baseline and 8-week follow-up. Participants were allocated to intervention (progressive strength training) or control (usual daily activities) groups. The intervention group trained 2 days per week during 8 weeks with elastic resistance. Intensity during the first 2 weeks was a 20-repetition maximum and increased progressively toward 15, 12, and finally 10 repetition maximum. The primary outcome was muscle strength. Secondary outcomes were the Timed "Up and Go" Test score, sit-to-stand, range of motion, Haemophilia Joint Health Score, kinesiophobia score, global impression of pain change, general self-rated health status, and desire to exercise.

RESULTS

The intervention group showed greater strength improvements than the control group in almost all of the joints, with moderate to high effect sizes. The intervention group also showed better Timed "Up and Go" and sit-to-stand scores than the control group (moderate effect size), greater range of motion at the knee flexion with the right leg (trivial effect size), and better Haemophilia Joint Health Score at the left knee (small effect size). The intervention group showed greater overall pain reduction, self-rated overall status, and desire to exercise than the control group.

CONCLUSIONS

Progressive strength training with elastic resistance performed twice a week during 8 weeks is safe and effective in people with hemophilia to improve muscle strength and functional capacity, reduce general pain, and improve self-rated health status and desire to exercise.

IMPACT

This study provides evidence for the use of a specific strength training regimen for people with hemophilia.

LAY SUMMARY

People with hemophilia of differing levels of severity, with adequate coverage with clotting factor, can safely engage in progressive strength training and can improve their functioning.

Prophylaxis for hemophilia A without inhibitors: treatment options and considerations

INTRODUCTION

Hemophilia A is a bleeding disorder traditionally managed with standard half-life (SHL) factor (F) VIII concentrates. Extended half-life (EHL) FVIII products and emicizumab-kywh, a nonfactor therapy, are newer treatment options. Additional nonfactor agents and gene therapy are expected to reach the market in the near future.

AREAS COVERED

A PubMed (MEDLINE) search from 1962 to April 2020 related to hemophilia A, its management, and the products currently available for prophylaxis was performed to comprehensively review these topics and analyze the benefits and drawbacks of each therapeutic.

EXPERT OPINION

Prophylaxis with SHL FVIII concentrates remains the standard of care for patients with severe hemophilia A and may also be considered for selected individuals with moderate disease. Several years of real-world experience with EHL FVIII, emicizumab-kywh, and other agents in development will be necessary to determine their ultimate roles in the prevention of bleeding and its complications. Gene therapy may not provide a permanent cure for hemophilia A.

Initial joint bleed volume in a delayed on-demand treatment setup correlates with subsequent synovial changes in hemophilic mice

BACKGROUND

Hemophilic arthropathy is a debilitating morbidity of hemophilia caused by recurrent joint bleeds. We investigated if the joint bleed volume, before initiation of treatment, was linked to the subsequent degree of histopathological changes and the development of bone pathology in a mouse model of hemophilic arthropathy.

METHODS

FVIII knock-out (F8-KO) mice were dosed with a micro-CT blood pool agent prior to induction of hemarthrosis. Eight hours after induction, the bleed volume was quantified with micro computed tomography (micro-CT) and recombinant FVIII treatment initiated. On Day 8, inflammation in the knees was characterized by fluorescence molecular tomography. On Day 14, knee pathology was characterized by micro-CT and histopathology. In a second study, contrast agent was injected into the knee of wild-type (WT) mice, followed by histopathological evaluation on Day 14.

RESULTS

The average joint bleed volume before treatment was 3.9 mm3. The inflammation-related fluorescent intensities in the injured knees were significantly increased on Day 8. The injured knees had significantly increased synovitis scores, vessel counts, and areas of hemosiderin compared to un-injured knees. However, no cartilage- or bone pathology was observed. The bleed volume before initiation of treatment correlated with the degree of synovitis and was associated with high fluorescent intensity on Day 8. In F8-KO and WT mice, persistence of contrast agent in the joint elicited morphological changes.

CONCLUSION

When applying a delayed on-demand treatment regimen to hemophilic mice subjected to an induced knee hemarthrosis, the degree of histopathological changes on Day 14 reflected the bleed volume prior to initiation of treatment.

In vivo fluorescence molecular tomography of induced haemarthrosis in haemophilic mice: link between bleeding characteristics and development of bone pathology

Background

Haemophilic arthropathy is a chronic and debilitating joint disease caused by recurrent spontaneous joint bleeds in patients with haemophilia. Understanding how characteristics of individual joint bleeds relate to the subsequent development of arthropathy could improve management and prevention of this joint disease. Here, we aimed to explore relations between joint bleed characteristics and development of bone pathology in a mouse model of haemophilic arthropathy by using novel in vivo imaging methodology.

Methods

We characterised induced knee bleeds in a murine model of haemophilic arthropathy by quantitative in vivo fluorescence molecular tomography (FMT) and by measurements of changes in the diameter of the injured knee. Wild-type mice and non-injured haemophilic mice acted as controls. Development of arthropathy was characterised by post mortem evaluation of bone pathology by micro-CT 14 days after bleed-induction. In an in vitro study, we assessed the effect of blood on the quantification of fluorescent signal with FMT.

Results

In most injured haemophilic mice, we observed significant loss of trabecular bone, and half of the mice developed pathological bone remodelling. Development of pathological bone remodelling was associated with significantly increased fluorescent signal and diameter of the injured knee just 1 day after induction of the bleed. Further, a correlation between the fluorescent signal 1 day after induction of the bleed and loss of trabecular bone reached borderline significance. In the in vitro study, we found that high concentrations of blood significantly decreased the fluorescent signal.

Conclusion

Our results add novel insights on the pathogenesis of haemophilic arthropathy and underline the importance of the acute phase of joint bleeds for the subsequent development of arthropathy.

Physical Activity Monitoring and Acceptance of a Commercial Activity Tracker in Adult Patients with Haemophilia

Physical activity (PA) is highly beneficial for people with haemophilia (PWH), however, studies that objectively monitor the PA in this population are scarce. This study aimed to monitor the daily PA and analyse its evolution over time in a cohort of PWH using a commercial activity tracker. In addition, this work analyses the relationship between PA levels, demographics, and joint health status, as well as the acceptance and adherence to the activity tracker. Twenty-six PWH were asked to wear a Fitbit Charge HR for 13 weeks. According to the steps/day in the first week, data were divided into two groups: Active Group (AG; ≥10,000 steps/day) and Non-Active Group (NAG; <10,000 steps/day). Correlations between PA and patient characteristics were studied using the Pearson coefficient. Participants' user experience was analysed with a questionnaire. The 10,000 steps/day was reached by 57.7% of participants, with 12,603 (1525) and 7495 (1626) being the mean steps/day of the AG and NAG, respectively. In general, no significant variations (p > 0.05) in PA levels or adherence to wristband were produced. Only the correlation between very active minutes and arthropathy was significant (r = -0.40, p = 0.045). Results of the questionnaire showed a high level of satisfaction. In summary, PWH are able to comply with the PA recommendations, and the Fitbit wristband is a valid tool for a continuous and long-term monitoring of PA. However, by itself, the use of a wristband is not enough motivation to increase PA levels.

Novel functions of inactive rhomboid proteins in immunity and disease

iRhoms are related to a family of intramembrane serine proteinases called rhomboids but lack proteolytic activity. In mammals, there are two iRhoms, iRhom1 and iRhom2, which have similar domain structures and overlapping specificities as well as distinctive functions. These catalytically inactive rhomboids are essential regulators for the maturation and trafficking of the disintegrin metalloprotease ADAM17 from the endoplasmic reticulum to the cell surface, and are required for the cleavage and release of a variety of membrane-associated proteins, including the IL-6 receptor, l-selectin, TNF, and EGFR ligands. iRhom2-dependent regulation of ADAM17 function has been recently implicated in the development and progression of several autoimmune diseases including rheumatoid arthritis, lupus nephritis, as well as hemophilic arthropathy. In this review, we discuss our current understanding of iRhom biology, their implications in autoimmune pathologies, and their potential as therapeutic targets.

TNF-α/TNF-R System May Represent a Crucial Mediator of Proliferative Synovitis in Hemophilia A

Hemophilic arthropathy (HA) typically begins with proliferative synovitis that shares some similarities with inflammatory arthritides, in which the proinflammatory cytokine tumor necrosis factor (TNF)-α has a crucial pathogenetic role. Inappropriate release of TNF-α was shown to contribute to arthropathy development following intra-articular bleeding in hemophilic mice. Here, we were interested in determining whether systemic levels of TNF-α and synovial tissue expression of the TNF-α/TNF receptor (TNF-R) system could be increased and related to joint damage in hemophilia A patients with severe HA. Serum levels of TNF-α measured by quantitative enzyme-linked immunosorbent assay (ELISA) were significantly increased in HA patients (n = 67) compared to healthy controls (n = 20). In HA patients, elevated TNF-α levels were significantly associated with the number of hemarthroses, the grade of synovial hypertrophy, and both the clinical World Federation of Hemophilia score and ultrasound score. The expression of TNF-α, TNF-R1, and TNF-R2 was strongly increased in HA synovium (n = 10) compared to the non-inflamed osteoarthritis control synovium (n = 8), as assessed by both immunohistochemistry and Western blotting. Increased protein levels of TNF-α, TNF-R1, and TNF-R2 were retained in vitro by HA fibroblast-like synoviocytes (n = 6) with respect to osteoarthritis control fibroblast-like synoviocytes (n = 6). Stimulation with TNF-α resulted in a significant increase in HA fibroblast-like synoviocyte proliferation quantified by the water-soluble tetrazolium (WST)-1 assay, while it had no relevant effect on osteoarthritis fibroblast-like synoviocytes. Quantification of active/cleaved caspase-3 by ELISA demonstrated that TNF-α did not induce apoptosis either in HA or in osteoarthritis fibroblast-like synoviocytes. The TNF-α/TNF-R system may represent a crucial mediator of proliferative synovitis and, therefore, a new attractive target for the prevention and treatment of joint damage in HA patients. Our findings provide the groundwork for further clinical investigation of anti-TNF-α therapeutic feasibility in hemophiliacs.

Upper-Body Exercises With External Resistance Are Well Tolerated and Enhance Muscle Activity in People With Hemophilia

BACKGROUND

Conventional nonresisted therapeutic exercises for people with hemophilia involve a careful, low-intensity approach to avoid injuries. Externally resisted exercise is highly efficient for increasing muscle strength in healthy adults but its feasibility for people with hemophilia remains unknown.

OBJECTIVE

The purpose of this study was to evaluate muscle activity during upper-body rehabilitation exercises with 2 types of external resistance and without external resistance (conventional) and to examine tolerability, kinesiophobia, and possible adverse effects derived from the session.

DESIGN

This was a cross-sectional study.

METHODS

Twelve people with hemophilia A/B (11 with severe hemophilia undergoing prophylactic treatment, 1 with mild hemophilia) participated. During the experimental session, participants completed the Tampa Scale of Kinesiophobia and performed 2 exercises-elbow flexion and shoulder abduction-with 3 conditions for each exercise: elastic resistance (externally resisted), free weights (externally resisted), and conventional nonresisted. Surface electromyography signals were recorded for the biceps brachii, triceps brachii, upper trapezius, and middle deltoid muscles. After the session, exercise tolerability and kinesiophobia were assessed. Adverse effects were evaluated 24 and 48 hours after the session.

RESULTS

Externally resisted exercises provided greater muscle activity than conventional nonresisted therapeutic exercises. The exercises were generally well tolerated and there was no change in kinesiophobia following the session. No adverse effects were observed in the following days.

LIMITATIONS

Small sample size was the main limitation.

CONCLUSIONS

In people with severe hemophilia undergoing prophylactic treatment, elbow flexion and shoulder abduction exercises with external resistance at moderate intensities are feasible and provide greater muscle activity than nonresisted conventional exercises.

Neuromuscular control during gait in people with haemophilic arthropathy

INTRODUCTION

Effects of haemophilic arthropathy on neuromuscular control during gait are currently unknown.

AIMS

(a) To assess how haemophilic arthropathy affects the complexity of neuromuscular control during gait; (b) To investigate the relationship between complexity of neuromuscular control and joint impairment.

METHODS

Thirteen control subjects (CG) walked overground at their preferred and a slow velocity and thirteen people with haemophilic arthropathy (PWHA) walking at their preferred velocity. Surface electromyography (EMG) was collected from eleven leg muscles. Electromyography variance explained by muscle synergies (sets of co-activated muscles that can be recruited by a single signal) was calculated by the total variance accounted (tVAF). Three measures were used to evaluate complexity of neuromuscular control: (a) the number of synergies required for tVAF > 90%, (b) tVAF as a function of the number of muscle synergies, and (c) the dynamic motor control index (Walk-DMC). Impairment of ankle and knee joints was determined by the Haemophilia Joint Health Score (HJHS).

RESULTS

The same number of the muscle synergies was found for each group (P > 0.05). For both walking velocities tested, tVAF1 was higher in PHWA (P < 0.05). The Walk-DMC of PWHA was lower than that of the CG for both walking velocities (P < 0.05). For PWHA, no significant correlation was found between HJHS (sum knee and ankle) and Walk-DMC index (r = -0.32, P = 0.28).

CONCLUSIONS

These results indicate differences between PWHA and CG in the neuromuscular control of gait. The Walk-DMC and tVAF1 may be useful measures to assess changes in neuromuscular control in response to treatment.

Bleed volume of experimental knee haemarthrosis correlates with the subsequent degree of haemophilic arthropathy

BACKGROUND

Haemophilic arthropathy is the main morbidity of haemophilia. The individual pathological response to the same number of clinically evident joint bleeds is highly variable; thus, it remains unknown if certain joint bleeding characteristics are critical for the development of arthropathy.

AIM

To study the relation between bleed volume and subsequent development of arthropathy, we aimed to develop quantitative in vivo imaging of active joint bleeds in a mouse model of haemophilia.

METHODS

Haemophilia A (F8-KO) and wild-type (WT) mice were IV-dosed with a micro-CT blood pool contrast agent prior to an induced knee haemarthrosis or sham procedure. The mice were micro-CT scanned five times the following 2 days to characterise and quantify the induced haemarthrosis in vivo. On Day 14, the mice were euthanized and pathological changes evaluated by histology and micro-CT. Additionally, bleeding characteristics in vehicle-treated F8-KO mice were compared with those of recombinant FVIII (rFVIII)-treated F8-KO mice.

RESULTS

F8-KO mice had a significantly larger bleed volume than WT mice at all scan time points. The bleed volume 12 hours after induction of haemarthrosis correlated with the subsequent degree of arthropathy. Presence of µCT-detectable bone pathology was associated with a significantly increased bleed volume among F8-KO mice. rFVIII treatment significantly reduced bleed volume in F8-KO mice.

CONCLUSION

Quantitative in vivo contrast-enhanced micro-CT imaging can be used to characterize and quantify joint bleeds in a mouse model of haemophilic arthropathy. The bleed volume correlates with the subsequent degree of arthropathy.

Blood-induced bone loss in murine hemophilic arthropathy is prevented by blocking the iRhom2/ADAM17/TNF-α pathway

Hemophilic arthropathy (HA) is a debilitating degenerative joint disease that is a major manifestation of the bleeding disorder hemophilia A. HA typically begins with hemophilic synovitis that resembles inflammatory arthritides, such as rheumatoid arthritis, and frequently results in bone loss in patients. A major cause of rheumatoid arthritis is inappropriate release of the proinflammatory cytokine tumor necrosis factor-α (TNF-α) by the TNF-α convertase (TACE; also referred to as ADAM17) and its regulator, iRhom2. Therefore, we hypothesized that iRhom2/ADAM17-dependent shedding of TNF-α also has a pivotal role in mediating HA. Here, we show that addition of blood or its components to macrophages activates iRhom2/ADAM17-dependent TNF-α shedding, providing the premise to study the activation of this pathway by blood in the joint in vivo. For this, we turned to hemophilic FVIII-deficient mice (F8-/- mice), which develop a hemarthrosis following needle puncture injury with synovial inflammation and significant osteopenia adjacent to the affected joint. We found that needle puncture-induced bleeding leads to increased TNF-α levels in the affected joint of F8-/- mice. Moreover, inactivation of TNF-α or iRhom2 in F8-/- mice reduced the osteopenia and synovial inflammation that develops in this mouse model for HA. Taken together, our results suggest that blood entering the joint activates the iRhom2/ADAM17/TNF-α pathway, thereby contributing to osteopenia and synovitis in mice. Therefore, this proinflammatory signaling pathway could emerge as an attractive new target to prevent osteoporosis and joint damage in HA patients.

HemoKinect: A Microsoft Kinect V2 Based Exergaming Software to Supervise Physical Exercise of Patients with Hemophilia

Patients with hemophilia need to strictly follow exercise routines to minimize their risk of suffering bleeding in joints, known as hemarthrosis. This paper introduces and validates a new exergaming software tool called HemoKinect that intends to keep track of exercises using Microsoft Kinect V2's body tracking capabilities. The software has been developed in C++ and MATLAB. The Kinect SDK V2.0 libraries have been used to obtain 3D joint positions from the Kinect color and depth sensors. Performing angle calculations and center-of-mass (COM) estimations using these joint positions, HemoKinect can evaluate the following exercises: elbow flexion/extension, knee flexion/extension (squat), step climb (ankle exercise) and multi-directional balance based on COM. The software generates reports and progress graphs and is able to directly send the results to the physician via email. Exercises have been validated with 10 controls and eight patients. HemoKinect successfully registered elbow and knee exercises, while displaying real-time joint angle measurements. Additionally, steps were successfully counted in up to 78% of the cases. Regarding balance, differences were found in the scores according to the difficulty level and direction. HemoKinect supposes a significant leap forward in terms of exergaming applicability to rehabilitation of patients with hemophilia, allowing remote supervision.