2023 French recommendations for diagnosing and managing prepatellar and olecranon septic bursitis

Septic bursitis (SB) is a common condition accounting for one third of all cases of inflammatory bursitis. It is often related to professional activities. Management is heterogeneous and either ambulatory or hospital-based, with no recommendations available. This article presents recommendations for managing patients with septic bursitis gathered by 18 rheumatologists from the French Society for Rheumatology work group on bone and joint infections, 1 infectious diseases specialist, 2 orthopedic surgeons, 1 general practitioner and 1 emergency physician. This group used a literature review and expert opinions to establish 3 general principles and 11 recommendations for managing olecranon and prepatellar SB. The French Health authority (Haute Autorité de santé [HAS]) methodology was used for these recommendations. Designed for rheumatologists, general practitioners, emergency physicians and orthopedic surgeons, they focus on the use of biological tests and imaging in both outpatient and inpatient management. Antibiotic treatment options (drugs and duration) are proposed for both treatment modalities. Finally, surgical indications, non-drug treatments and prevention are covered by specific recommendations.

Biology and physiology of tendon healing

Tendon disorders affect people of all ages, from elite and recreational athletes and workers to elderly patients. After an acute injury, 3 successive phases are described to achieve healing: an inflammatory phase followed by a proliferative phase, and finally by a remodeling phase. Despite this process, healed tendon fails to recover its original mechanical properties. In this review, we proposed to describe the key factors involved in the process such as cells, transcription factors, extracellular matrix components, cytokines and growth factors and vascularization among others. A better understanding of this healing process could help provide new therapeutic approaches to improve patients' recovery while tendon disorders management remains a medical challenge.

A prospective study of 100 patients with rotator cuff tendinopathy showed no correlation between subacromial bursitis and the efficacy of ultrasound-guided corticosteroid injection

OBJECTIVES

The objective of this study was to determine whether the presence of subacromial bursitis in patients with rotator cuff tendinopathy (RCT) was associated with a better outcome after ultrasound (US)-guided subacromial corticosteroid injection.

METHODS

A single-center prospective study was performed including patients referred for subacromial injection to manage RCT. At baseline, all patients received an US-guided intra-bursal injection of betamethasone (1 ml). The primary endpoint was reduced pain 3 months (M3) after the procedure: a good responder was defined by a decrease in Visual Analogue Scale pain of more than 30%. Secondary endpoints included functional recovery assessed by the Oxford Shoulder Score (OSS) and clinical success at 6 weeks (W6). We also explored the association between good clinical response and other factors, such as US or X-ray features.

RESULTS

One hundred patients were included and 49 presented with subacromial bursitis. At M3, 60% of patients (54/100) were considered good responders. The rate of good responders did not differ between the bursitis and non-bursitis groups (p = 0.6). During follow-up, OSS improved over time whether bursitis was present or not. We did not find any US or X-ray features significantly associated with a favorable clinical outcome.

CONCLUSION

The presence of subacromial bursitis did not influence clinical outcomes at 3 months post-subacromial injection in patients suffering from RCT.

CLINICAL RELEVANCE STATEMENT

The presence of subacromial bursitis did not influence clinical outcomes at 3 months post-subacromial corticosteroid injection in patients with rotator cuff tendinopathy. For patient management, looking for ultrasonographic signs of bursitis does not appear relevant for the indication of the injection.

KEY POINTS

• Ultrasound-guided subacromial corticosteroid injections led to a significant improvement in 60% of patients suffering from rotator cuff tendinopathy. • The presence of subacromial bursitis was not associated with better improvement at 3 months post-injection. • Except for the Minnesota score referring to job satisfaction, we did not find any baseline clinical, X-ray, or ultrasound characteristics associated with a successful outcome.

Development of a new radiographic score for the follow-up of calcific tendinopathy of the rotator cuff

OBJECTIVES

The aim of this study was to evaluate the psychometric properties of a new x-ray scoring system for calcific tendinopathy of the rotator cuff (CTRC).

METHODS

This is a post-hoc analysis of the CALCECHO trial. All patients received an ultrasound-guided puncture and lavage of their calcification. Clinical data and x-rays from baseline and follow-up visits at 7 days (D7), 3 months (M3) and 12 months (M12) were used. The scoring system was based on the reduction in size and density of the calcification compared to the initial x-ray (0 = no change; 1 = decrease of less than 50%; 2 = decrease of between 50 and 90%; 3 = decrease of more than 90%; 4 = complete disappearance). Inter-observer and intra-observer reliability were established between 3 independent investigators (2 experts and one junior) using weighted Kappa calculation. Construct validity was assessed as well as predictive validity and sensitivity to change.

RESULTS

Between the two experts, inter-reader reliability was at 0.677, 0.744 and 0.656 at D7, M3 and M12 respectively. Intra-reader reliability was between 0.577 and 0.836 for the two expert readers and between 0.519 and 0.697 for the junior reader. Our score was correlated with shoulder pain and function at M3 and M12 and the score at M3 was predictive of the clinical outcome at M12. Finally, sensitivity to change was 0.8.

CONCLUSIONS

Our new score presented good psychometric properties and was correlated with clinical data. It could be useful in the follow-up of patients treated for CTRC.

Knockdown of biglycan reveals an important role in maintenance of structural and mechanical properties during tendon aging

Biglycan, a small leucine-rich proteoglycan (SLRP), is involved in collagen fibrillogenesis and also acts as a signaling molecule. Although decorin has been considered as the primary SLRP in developing and maintaining tendon structure and mechanics, more recent work using inducible knockdown models suggests that biglycan is involved in tendon homeostasis. The purpose of the study was to determine the role of biglycan in tendon homeostasis to maintain mechanical and structural integrity in aged mice. Aged (485 days old) female Bgn+/+ control (wild type [WT], n = 16) and 16 bitransgenic conditional Bgnflox/flox mice (I-Bgn-/- , n = 16) with a tamoxifen-inducible Cre (driven by ROSA) were utilized. After biglycan knockdown, the transgenic model demonstrated effective knockdown of the target gene without any compensation from other SLRPs or type I collagen. Patellar tendon cellularity was not modified after biglycan knockdown. However, biglycan knockdown had an impact on collagen fibrillogenesis with a higher percentage of small diameter fibrils (25-45 nm) and a lower percentage of medium size fibrils (150-165 nm) in I-Bgn-/- tendons. Biglycan knockdown also induced a reduction in the midsubstance modulus and maximum stress compared to WT. Stress relaxation was reduced at 4% strain in I-Bgn-/- tendons but no changes were observed in dynamic modulus and tan delta. As in mature tendons (120 days old), this study showed significant effects of biglycan knockdown on mechanical and structural properties of aged tendons only 30 days after knockdown. These data suggest that biglycan has a major role in maintaining homeostasis in aged tendon.

Update on contribution of hip labral tears to hip pain: A narrative review

Hip labral tears are found in 22-55% of individuals with hip pain, but labral tears without cysts are usually not responsible for hip pain, which originates mostly from other structures than the torn labrum, like osteochondral, but also tendinous injuries (rectus femoris, gluteus minimus, iliopsoas) or capsulo-ligamentous tears (iliofemoral ligaments, ligament teres). Those lesions are mainly the consequences of underlying unrecognized functional acetabular dysplasia, and/or femoroacetabular impingements. Although the early repair of labral tears in young sportsmen induces a marked and lasting relief, and might delay the onset of osteoarthritis, the microinstability fostered by labral damages seems less important than underlying dysplasias/impingements. This narrative review details recent findings on: (i) the various mechanisms of pain associated with labral tears; (ii) few evidence for hip microinstability induced by isolated labral tears; (iii) how to best detect labral tears, both clinically (including through IROP test) and on imaging (MRI, MRA, computed tomography arthrography, ultrasound). Some authors suggested to use pull-out tests during surgery, but pulling of hips do not seem to increase much diagnostic performances of ultrasounds. Ultrasound-guided intra-articular and peri-articular injections may tell how often hip pain is exclusively induced by peri-capsular injuries secondary to the acetabular dysplasia/femoro-acetabular impingements already responsible for labral tears. Further works could tell whether labral repair, tendinous debridement, plication of capsule, and/or focal denervation, may induce lasting reliefs of pain induced by the chronic contraction of surrounding muscles (rectus femoris, gluteus minimus, psoas), whose deep aponeuroses mix with the superficial fibres of the thick hip capsule.

Contribution of HLA DRB1, PTPN22, and CTLA4, to RA dysbiosis

This narrative review gathers current evidence for a contribution of rheumatoid arthritis (RA) HLA-DRB1, PTPN22 and CTLA4 polymorphisms to the gut dysbiosis observed in RA, especially at its onset (transient excess of Prevotella). The gut microbiome contains elements which are 30% heritable, including genera like Bacteroides and Veillonella, and to a lesser extent Prevotella. The first months/year seems a critical period for the selection of a core of microbiota, that should be considered as a second self by the immune system, and tolerized by regulatory T and B cells. Imperfect tolerization may increase the risk of RA following further repeated silent translocations of various gut microorganisms, including Prevotella copri, from gut to joints (fostered by a concurrent loss in gut mucosa of protective bacteria like Faecalibacterium prausnitzii). Genetics studies confirmed that Prevotella copri was partly heritable, and strong associations were observed between the overall microbial composition of stools and the HLA-DRB1 RA risk allele, either in a US cohort (P=0.00001), or the Twins UK cohort (P=0.033). This finding also stands for persons still free from RA, and was replicated in the Swiss SCREEN-RA cohort. Gene variants of PTPN22 also modify intestinal microbiota composition, compromise granulocyte-mediated antibacterial defence in gut, and reduce the suppressive effect of gut regulatory B cells. CTLA4 variants may similarly contribute to RA dysbiosis, since immunotherapy by CTLA-4 blockade depends on microbiota, and CTLA4 activates T follicular regulatory cells to reduce immune responses to segmented filamentous bacteria. Suggestions for future works are made.

Management and outcome of native joint septic arthritis: a nationwide survey in French rheumatology departments, 2016-2017

OBJECTIVES

To describe current management and outcome of native joint septic arthritis (NJSA) in French rheumatology departments.

METHODS

For this retrospective, nationwide multicentric study, 127 French rheumatology departments were contacted to report up to 12 cases of NJSA that occurred between 1 January 2016 and 31 December 2017. Characteristics, diagnosis procedures, therapeutic management and outcome were recorded.

RESULTS

Overall, 362 patients were included (mean age 64.0±18.6 years, median Charlson comorbidity index 3.5 (0-14)). Knee was the most frequent site (n=160 (38.9%)), and Staphylococcus sp (n=185 (51.4%)), the most frequent pathogen. All patients received antibiotics for a mean duration of 46.8 (±22.0) days, including intravenous route for a mean of 17.2 (±15.4) days. Management was heterogeneous. Surgical procedure was performed in 171 (48.3%), joint immobilisation in 128 (43.8%). During follow-up, 91 (28.3%) patients have had serious complications and 28 (9.2%) of them died. Factors associated with 1-year mortality were age (OR 1.08, 95% CI 1.04 to 1.13; p<0.001), Charlson's index (OR 1.30, 95% CI 1.06 to 1.58; p=0.012), presence of bacteraemia (OR 4.02, 95% CI 1.35 to 11.99; p=0.008), antibiotic use in the previous 3 months (OR 3.32, 95% CI 1.11 to 9.87; p=0.029) and Staphylococcus aureus NJSA compared with Streptococcus sp. NJSA (OR 7.24, 95% CI 1.26 to 41.68, p=0.027). The complete recovery with no adverse joint outcome at 1 year was observed in n=125/278 patients (55.0%).

CONCLUSION

Prognosis of NJSA remained severe with a high rate of morbimortality. Its management was very heterogeneous. This study highlights the importance of the new French recommendations, published after the completion of the study, in order to facilitate NJSA management.

Clinical characteristics and management of olecranon and prepatellar septic bursitis in a multicentre study

BACKGROUND

No current guidelines are available for managing septic bursitis (SB).

OBJECTIVES

To describe the clinical characteristics and management of olecranon and prepatellar SB in five French tertiary care centres.

METHODS

This is a retrospective observational multicentre study. SB was diagnosed on the basis of positive cultures of bursal aspirate. In the absence of positive bursal fluid, the diagnosis came from typical clinical presentation, exclusion of other causes of bursitis and favourable response to antibiotic therapy.

RESULTS

We included 272 patients (median age of 53 years, 85.3% male and 22.8% with at least one comorbidity). A microorganism was identified in 184 patients (67.6%), from bursal fluids in all but 4. We identified staphylococci in 135 samples (73.4%), streptococci in 35 (19%) and 10 (5.5%) were polymicrobial, while 43/223 bursal samples remained sterile (19.3%). Forty-nine patients (18%) were managed without bursal fluid analysis. Antibiotic treatment was initially administered IV in 41% and this route was preferred in case of fever (P = 0.003) or extensive cellulitis (P = 0.002). Seventy-one (26%) patients were treated surgically. A low failure rate was observed (n = 16/272, 5.9%) and failures were more frequent when the antibiotic therapy lasted <14 days (P = 0.02) in both surgically and medically treated patients.

CONCLUSIONS

Despite variable treatments, SB resolved in the majority of cases even when the treatment was exclusively medical. The success rate was equivalent in the non-surgical and the surgical management groups. However, a treatment duration of <14 days may require special attention in both groups.

Fibromyalgia and Associated Disorders: From Pain to Chronic Suffering, From Subjective Hypersensitivity to Hypersensitivity Syndrome

The concept of fibromyalgia has progressed to achieve a certain consensus regarding the definition of the condition. We summarize what is known in 2020, be it in terms of diagnosis, with the criteria that have changed over the years, or at the level of the psychological profile, via the notions of "catastrophizing" and "coping" and post-traumatic syndrome. The importance of fatigue and sleep disorders is underlined, with the chronological sequence of post-traumatic syndrome, chronic fatigue, and then amplification of the pain and the onset of multiple associated symptoms. The etiopathogenic debate has been enriched thanks to neuro-imaging data to discover the start of the central neurological signature. The many associated symptoms are reanalyzed in the context of so-called sister conditions which form sometimes more or less separate entities, such as chronic fatigue syndrome or restless legs syndrome for example. What these conditions have in common is hypersensitivity, not just to pain, but also to all exteroceptive stimuli, from deep sensitivity in the neuro-vegetative system, the sense organs and certain functions of the central nervous system, to the psychological aspects and sleep control. In summary, it is possible to define fibromyalgia as a cognitive disorder of cortical integration of chronic pain, with amplification of painful and sensory nociception, decrease in the threshold for the perception of pain, and persistence of a stimulus that maintains the process in chronicity. Fibromyalgia is part of a group of chronic hypersensitivity syndromes of central origin, with a very wide range of means of expression.

Contribution of mycobiota to the pathogenesis of spondyloarthritis

This review lists current evidences for a contribution of gut mycobiota to the pathogenesis of SpA and related conditions. Gut mycobiota has a small size as compared to bacterial microbiota, but an even greater inter- and intra-individual variability. Although most fungi (brought by food or air) are only transitory present, a core mycobiota of gut resident fungi exists, and interplays with bacteria in a complex manner. A dysbiosis of this gut mycobiota has been observed in Crohn's disease and sclerosing cholangitis, with decreased proportion of Saccharomyces cerevisiae and outgrowth of more pathogenic gut fungi. Fungal-induced lower number of commensal gut bacteria can promote translocation of some bacterial/fungal antigens through mucosae, and live fungi can also cross the epithelial border in Crohn's disease. This dysbiosis also lower the ability of bacteria to metabolize tryptophan into regulatory metabolites, consequently enhancing tryptophan metabolism within human cells, which might contribute to fatigue. Translocation of mycobiotal antigens like curdlan (beta-glucan), which plays a major role in the pathogenesis of SpA in the SGK mice, has been observed in humans. This translocation of fungal antigens in human SpA might account for the anti-Saccharomyces antibodies found in this setting. Contribution of fungal antigens to psoriasis and hidradenitis suppurativa would fit with the preferential homing of fungi in the skin area most involved in those conditions. Fungal antigens also possess autoimmune uveitis-promoting function. As genes associated with SpA (CARD9 and IL23R) strongly regulate the innate immune response against fungi, further studies on fungi contribution to SpA are needed.

POS0366 PRO-INFLAMMATORY EFFECTS OF HUMAN APATITE CRYSTALS EXTRACTED FROM PATIENTS SUFFERING FROM CALCIFIC TENDINOPATHY

Background:

Calcific tendonitis of the rotator cuff is due to carbonated apatite deposits in the shoulder tendons. During the evolution of the disease, an acute inflammatory episode may occur leading to the disappearance of the calcification. Although hydroxyapatite crystals-induced inflammation has been previously studied with synthetic crystals, no data are available with calcifications extracted from patients suffering from calcific tendinopathy. The objective of the study was to explore the inflammatory properties of human calcifications and the pathways involved.

Objectives:

The objective of the study was to explore the inflammatory properties of human calcifications and the pathways involved.

Methods:

Human calcifications were obtained from patients treated for their shoulder pain related to a calcific tendinopathy of the rotator cuff. Calcifications were extracted by ultrasound-guided lavage and aspiration as previously described [1]. Human calcifications and synthetic hydroxyapatite (sHA) were used in vitro to stimulate human monocytes and macrophages, the human myeloid cell line THP-1 and human tenocytes. The release of IL-1β, IL-6 and IL-8 by cells was quantified by ELISA. Gene expression of pro- and anti-inflammatory cytokines was evaluated by quantitative PCR. NF-kB activation and NLRP3 involvement was assessed in THP-1 cells using a NF-kB inhibitor and a Caspase 1 inhibitor. The inflammatory properties were then assessed in vivo using a mouse air pouch model. The membrane thickness and infiltrate were assessed 6 and 24 hours after the injection of human calcifications or synthetic hydroxyapatite using hematoxylin and eosin staining. Macrophages, neutrophils and lymphocytes infiltrates were assessed by immunohistochemistry. Total RNA was extracted from the membranes and expression of IL-1β, IL-6 and TNFβ was quantified by PCR.

Results:

Human calcifications were able to induce a significant release of IL-1β when incubated with monocytes, macrophages and THP-1 only if they were first primed with LPS (lipopolysaccharide) for monocytes and macrophages or PMA (Phorbol 12-myristate 13-acetate) for THP-1. No IL-1β was detected in tenocytes’ supernatants. Stimulation of THP-1 by human calcifications led to similar levels of IL-1β when compared to synthetic hydroxyapatite although these levels were significantly inferior in monocytes and macrophages. IL-6 and IL-8 levels were not increased in the supernatants after crystal stimulation. Patient’s crystals enhanced mRNA expression of pro-IL-1β, as well as IL-18, NF-kB and TGFβ when IL-6 and TNFα expression were not. IL-1β production was reduced by the inhibition NF-kB as well as Caspase 1 indicating the role of NLRP3 inflammasome. In vivo, injection of human calcifications or synthetic hydroxyapatite in air pouch led to significant increase in membrane thickness with an infiltrate mainly composed of macrophages. Significant overexpression of IL-1β was only observed in the synthetic hydroxyapatite group.

Conclusion:

As synthetic hydroxyapatite, human calcifications were able to induce an inflammatory response resulting in the production of IL-1β after NF-kB activation and through NLRP3 inflammasome. In some experiments, IL-1β induction was lower with human calcifications compared to synthetic apatite. Differences in size, shape and protein content may explain this observation.

References:

[1]Darrieutort-Laffite C, Arnolfo P, Garraud T, Adrait A, Couté Y, Louarn G, et al. Rotator Cuff Tenocytes Differentiate into Hypertrophic Chondrocyte-Like Cells to Produce Calcium Deposits in an Alkaline Phosphatase-Dependent Manner. J Clin Med. 2019 Sep 26;8(10):1544. doi: 10.3390/jcm8101544.

Acknowledgements:

Fondation Arthritis, Recherche et Rhumatismes and French Society for Rheumatology for their financial support

Disclosure of Interests:

None declared

Pro-inflammatory effects of human apatite crystals extracted from patients suffering from calcific tendinopathy

BACKGROUND

Calcific tendonitis of the rotator cuff is due to carbonated apatite deposits in the shoulder tendons. During the evolution of the disease, an acute inflammatory episode may occur leading to the disappearance of the calcification. Although hydroxyapatite crystal-induced inflammation has been previously studied with synthetic crystals, no data are available with calcifications extracted from patients suffering from calcific tendinopathy. The objective of the study was to explore the inflammatory properties of human calcifications and the pathways involved.

METHODS

Human calcifications and synthetic hydroxyapatite were used in vitro to stimulate human monocytes and macrophages, the human myeloid cell line THP-1, and human tenocytes. The release of IL-1β, IL-6, and IL-8 by cells was quantified by ELISA. The gene expression of pro- and anti-inflammatory cytokines was evaluated by quantitative PCR. NF-kB activation and NLRP3 involvement were assessed in THP-1 cells using a NF-kB inhibitor and a caspase-1 inhibitor. The inflammatory properties were then assessed in vivo using a mouse air pouch model.

RESULTS

Human calcifications were able to induce a significant release of IL-1β when incubated with monocytes, macrophages, and THP-1 only if they were first primed with LPS (monocytes and macrophages) or PMA (THP-1). Stimulation of THP-1 by human calcifications led to similar levels of IL-1β when compared to synthetic hydroxyapatite although these levels were significantly inferior in monocytes and macrophages. The patient's crystals enhanced mRNA expression of pro-IL-1β, as well as IL-18, NF-kB, and TGFβ when IL-6 and TNFα expression were not. IL-1β production was reduced by the inhibition of caspase-1 indicating the role of NLRP3 inflammasome. In vivo, injection of human calcifications or synthetic hydroxyapatite in the air pouch led to a significant increase in membrane thickness although significant overexpression of IL-1β was only observed for synthetic hydroxyapatite.

CONCLUSIONS

As synthetic hydroxyapatite, human calcifications were able to induce an inflammatory response resulting in the production of IL-1β after NF-kB activation and through NLRP3 inflammasome. In some experiments, IL-1β induction was lower with human calcifications compared to synthetic apatite. Differences in size, shape, and protein content may explain this observation.

Factors Associated With Clinical Improvement and the Disappearance of Calcifications After Ultrasound-Guided Percutaneous Lavage of Rotator Cuff Calcific Tendinopathy: A Post Hoc Analysis of a Randomized Controlled Trial

BACKGROUND

Calcific tendinitis of the rotator cuff is a frequent cause of shoulder pain. Ultrasound-guided percutaneous lavage (UGPL) is an effective treatment, but factors associated with good clinical and radiological outcomes still need to be identified.

PURPOSE

To study the clinical, procedural, and radiological characteristics associated with improved shoulder function and the disappearance of calcification on radiograph after UGPL.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

This is a post hoc analysis of the CALCECHO trial, a double-blinded randomized controlled trial conducted on 132 patients. The trial assessed the effect of corticosteroid injections after UGPL, and patients were randomly assigned to receive either corticosteroid or saline solution in the subacromial bursa. We analyzed all patients included in the randomized controlled trial as 1 cohort. We collected the patients' clinical, procedural, and radiological characteristics at baseline and during follow-up (3, 6, and 12 months). Univariable analysis, followed by multivariable stepwise regression through forward elimination, was performed to identify the factors associated with clinical success (Disabilities of the Arm, Shoulder and Hand [DASH] score <15) or the disappearance of calcification.

RESULTS

Good clinical outcomes at 3 months were associated with steroid injections after the procedure (odd ratio [OR], 3.143; 95% CI, 1.105-8.94). At 6 months, good clinical evolution was associated with a lower DASH score at 3 months (OR, 0.92; 95% CI, 0.890-0.956) and calcium extraction (OR, 10.7; 95% CI, 1.791-63.927). A lower DASH at 6 months was also associated with a long-term favorable outcome at 12 months (OR, 0.939; 95% CI, 0.912-0.966). Disappearance of calcification at 3 and 12 months occurred more frequently in patients in whom communication was created between the calcification and the subacromial bursa during the procedure (OR, 2.728 [95% CI, 1.194-6.234] at 3 months; OR, 9.835 [95% CI, 1.977-48.931] at 12 months). Importantly, an association between calcification resorption and good clinical outcome was found at each time point.

CONCLUSION

Assessing patients at 3 months seems to be an essential part of their management strategy. Calcium extraction and creating a communication between the calcific deposits and subacromial bursa are procedural characteristics associated with good clinical and radiological evolution.

Rheumatic involvement and bone scan features in Schnitzler syndrome: initial and follow-up data from a single-center cohort of 25 patients

Objective

To report on the characteristics and long-term course of rheumatic manifestations in Schnitzler syndrome (SchS).

Methods

A retrospective cohort study of patients with SchS followed between 2000 and 2020. Inclusion criteria included a diagnosis of SchS (Strasbourg criteria). All available bone scans were reviewed and scored according to the intensity and number of pathological sites. The scintigraphic score was compared with the clinical activity score, CRP level, and treatments.

Results

Twenty-five patients were included. Median age at diagnosis was 68 years. Eighty patients (72%) had SchS-related rheumatic pain. Most patients had a long-standing isolated rash before constitutional and/or rheumatic symptoms appeared. The monoclonal component level was usually very low (IgMκ in 22/25). Rheumatic pain predominated around the knees. Bone scans revealed abnormal tracer uptake in 15/18 (85%). The scintigraphic score correlated with clinical activity (r = 0.4, p < 0.02) and CRP level (r = 0.47, p < 0.01). The scintigraphic score was lower in patients receiving corticosteroids or IL1Ra (interleukin 1 receptor antagonist) than in untreated patients (median scores:2, 0, and 13, respectively; p < 0.05). Two patients developed Waldenström macroglobulinemia. Of the 22 surviving patients, median age at follow-up was 76 years. IL1Ra was used in 13 patients, with dramatic efficacy on both symptoms and bone scan features.

Conclusions

Rheumatic manifestations are very prevalent in SchS. However, bone pain can be misleading and contribute to misdiagnosis. Bone scan abnormalities are very prevalent and correlate with disease activity and treatments. IL1-Ra has a dramatic and durable efficacy but may not be required in every patient early on.

Molecular and Structural Effects of Percutaneous Interventions in Chronic Achilles Tendinopathy

Achilles tendinopathy (AT) is a common problem, especially in people of working age, as well as in the elderly. Although the pathogenesis of tendinopathy is better known, therapeutic management of AT remains challenging. Various percutaneous treatments have been applied to tendon lesions: e.g., injectable treatments, platelet-rich plasma (PRP), corticosteroids, stem cells, MMP inhibitors, and anti-angiogenic agents), as well as percutaneous procedures without any injection (percutaneous soft tissue release and dry needling). In this review, we will describe and comment on data about the molecular and structural effects of these treatments obtained in vitro and in vivo and report their efficacy in clinical trials. Local treatments have some impact on neovascularization, inflammation or tissue remodeling in animal models, but evidence from clinical trials remains too weak to establish an accurate management plan, and further studies will be necessary to evaluate their value.

Long-term follow up after denosumab treatment for osteoporosis - rebound associated with hypercalcemia, parathyroid hyperplasia, severe bone mineral density loss, and multiple fractures: a case report

BACKGROUND

The rebound effect after stopping treatment with denosumab may be associated with rapid loss of the gains in bone mineral density achieved with treatment, high levels of bone remodeling markers, the occurrence of vertebral fractures, and even hypercalcemia.

CASE PRESENTATION

A 64-year-old osteoporotic Caucasian woman suffered from a fracture of her second lumbar vertebra in 2004. From January 2005, she was treated with denosumab for 9 years, with good densitometry results for her hip and lumbar areas, and no fractures over the last 6 years of treatment. Ten months after the treatment with denosumab was stopped, a cascade of vertebral fractures, including some in unusual locations (third thoracic vertebra), and multiple rib fractures in a context of hypercalcemia, suggested possible malignancy. A complete evaluation, including systemic, biological, and biopsy analyses, ruled out this hypothesis. The hypercalcemia was associated with normal plasma phosphate and vitamin D concentrations, and a high parathyroid hormone level, with an abnormal fixation of the lower lobe of the thyroid on sesta-methoxy-isobutyl-isonitrile scintigraphy. Histological analysis of the excised parathyroid tissue revealed hyperplasia. The associated thyroidectomy (goiter) led to the discovery of a thyroid papillary microcarcinoma.

CONCLUSIONS

We consider the consequences of this rebound effect, not only in terms of the major loss of bone density (return to basal values within 3 years) and the multiple disabling fracture episodes, but also in terms of the hypercalcemia observed in association with apparently autonomous tertiary hyperparathyroidism. Several cases of spontaneous reversion have been reported in children, but the intervention in our patient precluded any assessment of the possible natural course. The discovery of an associated thyroid neoplasm appears to be fortuitous. Better understanding of the various presentations of the rebound effect after stopping treatment with denosumab would improve diagnostic management of misleading forms, as in this case. Bisphosphonates could partially prevent this rebound effect.

2020 French recommendations on the management of septic arthritis in an adult native joint

Septic arthritis (SA) in an adult native joint is a rare condition but a diagnostic emergency due to the morbidity and mortality and the functional risk related to structural damage. Current management varies and the recommendations available are dated. The French Rheumatology Society (SFR) Bone and Joint Infection Working Group, together with the French Language Infectious Diseases Society (SPILF) and the French Orthopaedic and Trauma Surgery Society (SOFCOT) have worked according to the HAS methodology to devise clinical practice recommendations to diagnose and treat SA in an adult native joint. One new focus is on the importance of microbiological documentation (blood cultures and joint aspiration) before starting antibiotic treatment, looking for differential diagnoses (microcrystal detection), the relevance of a joint ultrasound to guide aspiration, and the indication to perform a reference X-ray. A cardiac ultrasound is indicated only in cases of SA involving Staphylococcus aureus, oral streptococci, Streptococcus gallolyticus or Enterococcus faecalis, or when infective endocarditis is clinically suspected. Regarding treatment, we stress the importance of medical and surgical collaboration. Antibiotic therapies (drugs and durations) are presented in the form of didactic tables according to the main bacteria in question (staphylococci, streptococci and gram-negative rods). Probabilistic antibiotic therapy should only be used for patients with serious symptoms. Lastly, non-drug treatments such as joint drainage and early physical therapy are the subject of specific recommendations.

Inadequacies of the Lasègue test, and how the Slump and Bowstring tests are useful for the diagnosis of sciatica

Diagnosis of sciatica mainly relies on pain reproduction by stretching of the lumbar roots since neurological examination and medical history are usually not sufficient to guarantee diagnosis. The Lasègue test is the most popular method, which starts with the straight leg-raising test (SLR). However it is not perfect, and is not always well performed or interpreted. Passive ankle dorsiflexion at the end of the SLR (Bragard test) is more sensitive, but can also remain normal in some cases of sciatica. Other stretching tests can help to recognise lumbar root damage in patients with poorly defined pain in a lower extremity: firstly, the Christodoulides test, i.e. reproduction of L5 sciatic pain by a femoral stretch test; secondly, the Slump test, performed on a patient in a sitting position, by slowly extending their painful leg then passively bending their neck (or the opposite); and thirdly, the Bowstring test, which requires, at the end of the Lasègue test, once the knee has been slightly flexed, pressing on the course of the peroneal and/or tibial nerves in the popliteal fossea to try and reproduce the exact pain felt by the patient. The combination of all these tests takes less than 2minutes, and could improve both the sensitivity and specificity of the physical examination for the diagnosis of sciatica. This article is a review of the limitations of the Lasègue/SLR tests and of the efficacy of these other tests for stretching the lumbar roots.

AB0924 CALCIFIC TENDONITIS OF THE ROTATOR CUFF: PERIOSTIN ENRICHMENT IS ASSOCIATED WITH A BETTER RESPONSE TO ULTRASOUND-GUIDED PERCUTANEOUS LAVAGE

Background:

Calcific tendonitis of the rotator cuff is a frequent cause of chronic shoulder pain. It is due to apatite deposits within the tendons. Little data are currently available about proteins associated to crystals within deposits.

Objectives:

The aim of the study was to quantify 6 proteins in calcific powders obtained from patients who have undergone an ultrasound-guided percutaneous lavage (UGPL) of their calcification and to look for correlations between their concentration and patient characteristics.

Methods:

Calcific powders were obtained from patients included in the CALCECHO trial whose main objective was to compare post-procedure pain between two groups: methylprednisolone or placebo injected at the end of the lavage [1]. Based on preliminary proteomic data and literature data, the following proteins have been selected and quantified by ELISA: Pigment-epithelium Derived Factor (PEDF), Osteopontin (OPN), Periostin (POSTN), Activin A (ACT A), Osteoprotegerin (OPG) and Bone Morphogenic Protein-2 (BMP-2). The level of each protein was expressed in µg per pg of the total proteins present in the sample. These proteins have been selected for their link to the mineralization. Correlations between the level of each protein and radiographic and ultrasound appearance of the calcific deposits were sought. We also looked for correlations between level of each protein and duration of pain or response to UGPL (Mann-Whitney test).

Results:

Sixty-six samples were studied: mean age was 48.9 (+/- 9.7) and 68% were female. Mean duration of shoulder pain was 30 months with a mean VAS pain of 68/100 (+/-14). Mean calcification size was 1.8 cm. Results of ELISA were as follows: mean level of PEDF at 1097 pg/µg, mean level of OPG at 135 pg/µg, mean level of POSTN at 6.9 pg/µg, mean level of ACT A at 19.6 pg/µg and mean level of OPN at 49.6 pg/µg although BMP-2 was undetectable. There was no correlation between level of proteins and the size of the calcification or the duration of pain. There was no difference in protein levels between type A and type B calcifications on radiography (classification of the French Society for Arthroscopy). In contrast, levels of POSTN and OPN were significantly higher in nodular calcifications compared to the homogenous (p=0.003 and p=0.01 respectively) or fragmented types (p=0.03 and p=0.04 respectively). Furthermore, calcifications without acoustic shadowing were enriched in POSTN compared to those with (p=0.04). Finally, the periostin level was significantly higher in calcifications that have responded well to UGPL (p=0.02).

Conclusion:

In this cohort of patients treated by UGPL, we observed higher levels of POSTN and OPN in the less dense calcifications and POSTN enrichment appeared to be associated with a better response to UGPL. Considering these data, further studies will be necessary to better understand the role of this protein in calcific tendonitis.

References:

[1]Darrieutort-Laffite C, Varin S, Coiffier G, Albert JD, Planche L, Maugars Y, Cormier G, Le Goff B. Are Corticosteroid Injections Needed After Needling and Lavage of Calcific Tendinitis: A Randomized, Double-Blind, Non-Inferiority Trial. Ann Rheum Dis. 2019 Jun;78(6):837-843.

Disclosure of Interests:

None declared

Rotator Cuff Tenocytes Differentiate into Hypertrophic Chondrocyte-Like Cells to Produce Calcium Deposits in an Alkaline Phosphatase-Dependent Manner

Calcific tendonitis is a frequent cause of chronic shoulder pain. Its cause is currently poorly known. The objectives of this study were to better characterize the cells and mechanisms involved in depositing apatite crystals in human tendons. Histologic sections of cadaveric calcified tendons were analyzed, and human calcific deposits from patients undergoing lavage of their calcification were obtained to perform infrared spectroscopy and mass spectrometry-based proteomic characterizations. In vitro, the mineralization ability of human rotator cuff cells from osteoarthritis donors was assessed by alizarin red or Von Kossa staining. Calcifications were amorphous areas surrounded by a fibrocartilaginous metaplasia containing hypertrophic chondrocyte-like cells that expressed tissue non-specific alkaline phosphatase (TNAP) and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which are two key enzymes of the mineralization process. Calcific deposits were composed of apatite crystals associated with proteins involved in bone and cartilage development and endochondral bone growth. In vitro, tenocyte-like cells extracted from the rotator cuff were able to mineralize in osteogenic cultures, and expressed TNAP, type X COLLAGEN, and MMP13, which are hypertrophic chondrocytes markers. The use of a TNAP inhibitor significantly prevented mineral deposits. We provide evidence that tenocytes have a propensity to differentiate into hypertrophic chondrocyte-like cells to produce TNAP-dependent calcium deposits. We believe that these results may pave the way to identifying regulating factors that might represent valuable targets in calcific tendonitis.

Are corticosteroid injections needed after needling and lavage of calcific tendinitis? Randomised, double-blind, non-inferiority trial

OBJECTIVE

Steroid injections are common after an ultrasound-guided puncture and lavage (UGPL) of calcific tendonitis of the rotator cuff. However, steroids may prevent calcification resorption and negatively affect tendon healing. Our study was designed to determine whether saline solution was non-inferior to steroids in the prevention of acute pain reactions in the week following UGPL.

METHODS

This was a randomised, double-blinded, controlled non-inferiority trial with 12-month follow-up. We included 132 patients (66 in each group) with symptomatic calcification measuring more than 5 mm. Patients received 1 mL of saline or steroid (methylprednisolone 40 mg) in the subacromial bursa at the end of UGPL. Primary outcome was the maximal pain during the week following the procedure with a prespecified non-inferiority margin of 10 mm (0-100 visual analogue scale). Secondary outcomes included pain at rest and during activity, function (disabilities of the arm, shoulder and hand score) and radiological evolution of the calcification over the 12-month follow-up.

RESULTS

The estimated mean difference in the first week's maximal pain between these two groups was 11.76 (95% CI 3.78 to 19.75). Steroids significantly improved VAS pain at rest and during activities, as well as function at 7 days and 6 weeks. They did not change the rate of calcification resorption, which occurred in 83% and 74% of patients at 12 months in the saline and steroid groups.

CONCLUSION

Non-inferiority of saline when compared with steroids could not be established. However, steroid injection improved pain in the 6 weeks following the procedure, and function in the 3 months after, with no significant effect on calcification resorption.

TRIAL REGISTRATION NUMBER

NTC02403856.

Multiple Vertebral Osteonecroses (Kümmell's Disease) After 10 Years on Denosumab: Is Osteocyte Apoptosis to Blame?

We report here a case of multiple vertebral osteonecroses with intrasomatic gaseous dissection (Kümmell's disease) occurring 1 year after the end of a 10-year course of denosumab treatment for osteoporosis without fractures. Histomorphometry and bone remodeling markers revealed major bone resorption and the persistence of an inhibition of bone formation. The presence of multiple empty lacunae in the bone provided evidence for high levels of osteocyte apoptosis. Osteocytes direct bone resorption (via the RANK/RANK-L/osteoprotegerin system) and formation (Wnt system, with SOST and DKK1) pathways. The vertebral osteonecrosis in our case may, therefore, have resulted from osteocyte apoptosis, decompensated by the sudden reactivation of bone remodeling after the cessation of denosumab treatment.

Detection of a lumbar foraminal venous varix by Color Doppler Ultrasound

Ultrasonography is currently widely used in the rheumatology practice. Although mainly performed to study peripheral joint, several articles have underlined its interest to study spinal anatomy. However, its ability to provide diagnostic features is unknown. We studied the case of a 25-year-old woman having low back pain. Three different imaging modalities (Computed Tomography [CT], Magnetic Resonance Imaging [MRI] and Ultrasound) were used to explore it. CT and MRI showed a foraminal dilation of the lombo-ovarian vein at the L3-L4 level with a scalloping of the lateral edge of L3. We were able to detect it with Color Doppler Ultrasound and a malformation of the inferior vena cava was also found. We showed for the first time that Color Doppler Ultrasound can detect venous malformation of the spine. This imaging modality could help us in the diagnosis of atypical lesions of the spine to confirm their vascular origin.

Sodium (18)F-sodium fluoride PET failed to predict responses to TNFα antagonist therapy in 31 patients with possible spondyloarthritis not meeting ASAS criteria

OBJECTIVES

To determine whether (18)F-NaF positron-emission tomography (PET) contributes to the diagnosis of spondyloarthritis and whether observed uptakes predict the response to TNFα antagonist therapy.

METHODS

We studied patients who had suspected spondyloarthritis but did not meet ASAS criteria and who were referred for an assessment of eligibility for TNFα antagonist therapy. (18)F-NaF PET was offered instead of bone scintigraphy. TNFα antagonist therapy was given if the clinician's level of confidence in the diagnosis of spondyloarthritis based on (18)F-NaF PET findings was ≥50/100.

RESULTS

Thirty-one patients accepted to undergo (18)F-NaF PET. Their mean age was 39.9±11.7 years; 22% were HLA-B27-positive and none had evidence of sacroiliitis by magnetic resonance imaging. Of the 31 patients, 30 had abnormal (18)F-NaF PET findings. However, of the 312 high-uptake foci, only 123 (39.4%) matched sites of pain. TNFα antagonist therapy was given to 16 patients. The treated group and untreated group (n=15) were not significantly different for the mean number of high-uptake foci per patient (11.7±8.1 vs. 8.3±5.1, respectively) or for the proportion of patients with high uptake by the sacroiliac joints (13/16 [81%] vs. 8/15 [53%], respectively). In the treated group, 5 patients met ASAS response criteria after 3 months. These 5 patients were among the 9 treated patients who met Amor's modified criteria (arthritis instead of asymmetrical oligoarthritis). In the 5 responders, the (18)F-NaF uptake scores were nonsignificantly lower than in the 11 nonresponders (9.0±8.5 vs. 13.0±6.4, respectively). In the patients for whom the (18)F-NaF PET findings increased the level of confidence in the diagnosis of spondyloarthritis, this effect was short-lived.

DISCUSSION

The positive predictive value of (18)F-NaF PET for diagnosing spondyloarthritis or predicting a response to TNFα antagonist therapy seems very low. This finding is probably ascribable to poor specificity.