UK community prevalence of knee chondrocalcinosis: evidence that correlation with osteoarthritis is through a shared association with osteophyte

Crowned dens syndrome presenting as pyrexia of unknown origin (PUO)

BACKGROUND

Deposition of calcium pyrophosphate crystals in the cervical spine around the odontoid process may lead to neck pain and fever. This condition is called crowned dens syndrome (CDS).

CASE REPORT

An 89-year-old female presented with complaints of fever for one-month duration and recent onset neck pain. During her admission, she developed right knee pain with evidence of chondrocalcinosis on X-ray. Considering her clinical presentation in setting of pseudogout, she had a CT scan of her neck that revealed erosion of the dens and hyperdense soft tissue surrounding the odontoid process. Based on her clinical and radiologic presentation, she was diagnosed with crowned dens syndrome and started on NSAIDs. Unfortunately, she did not respond to NSAIDs and was switched to Colchicine, which resulted in immediate improvement in her symptoms.

CONCLUSIONS

We present this case to stress the importance of keeping crowned dens syndrome as one of the differentials in an elderly patient presenting with fever and neck pain.

Calcium crystal deposition diseases - beyond gout

The most common types of calcium-containing crystals that are associated with joint and periarticular disorders are calcium pyrophosphate dihydrate (CPP) and basic calcium phosphate (BCP) crystals. Several diverse but difficult-to-treat acute and chronic arthropathies and other clinical syndromes are associated with the deposition of these crystals. Although the pathogenic mechanism of calcium crystal deposition is partially understood, much remains to be investigated, as no drug is available to prevent crystal deposition, permit crystal dissolution or specifically target the pathogenic effects that result in the clinical manifestations. In this Review, the main clinical manifestations of CPP and BCP crystal deposition are discussed, along with the biological effects of these crystals, current therapeutic approaches and future directions in therapy.

Calcium Pyrophosphate Deposition Disease Involving a Lumbar Facet Joint Following Urinary Tract Infection

A 75-year-old woman was admitted with urosepsis due to Escherichia coli infection. After improvement with a ureteral stent and antimicrobial agent, she complained of back pain and showed elevated inflammation marker levels. Arthralgia and arthritis of multiple peripheral joints were noted, and radiography indicated cartilage calcification. Magnetic resonance imaging revealed lumbar facet joint effusion. Her symptoms improved with nonsteroidal anti-inflammatory drug administration. Thus, she was diagnosed with calcium pyrophosphate deposition (CPPD)-related facet joint arthritis (FJA) rather than infectious FJA. CPPD-related FJA is an important differential diagnosis in elderly individuals with a risk of CPPD disease who complain of back pain.

Asymptomatic focal calcium pyrophosphate crystal deposition within partially failed repair tissue after matrix-assisted autologous chondrocyte implantation

Possible failures of autologous chondrocyte implantation (ACI), a cell-based technique for articular cartilage repair, are not always clinically apparent and the underlying mechanisms largely remain unknown. This case report presents the first scenario in the literature highlighting an association of a medium-term partial failure of an advanced ACI procedure (matrix-assisted ACI) in the knee with focal asymptomatic calcium pyrophosphate deposition disease, a common inflammatory pyrophosphate arthropathy. The specific presence of CPPDs, resulting from increased biomechanical stresses in the repair tissue-cartilage and repair tissue-subchondral bone integration sites, together with the absence of cartilage regeneration was identified and possibly contributed to the partial failure.Level of evidence V.

Prevalence of chondrocalcinosis in a Mexican tertiary care institution of musculoskeletal disorders

INTRODUCTION/OBJECTIVES

The prevalence of chondrocalcinosis (CC) was reported as variable according to the geographic populations. However, there are no data regarding its prevalence in Mexico. Thus, we decided to investigate the Mexican prevalence of CC in a cohort of patients from a tertiary health care institution.

METHODS

A retrospective analysis of radiographs of knees and wrists from our institution was performed. Inclusion criteria included patients > 50 years old having radiographs of knees and wrists. Radiographic presence of CC was classified according to a dichotomous evaluation assayed by two rheumatologists experts on the area.

RESULTS

A total of 3.350 radiographs from 1.602 patients were evaluated. Forty-seven patients showed calcifications in at least one knee or wrist for an overall prevalence of 3%, of which 23.4% were men and 76.6% women. The knee was more commonly affected than the wrist (85.1% and 14.9% respectively). The prevalence according to gender was 2.9% in women, whereas, it was 3.2% in men. Only two patients (4.3%) showed a contemporaneous presence of CC in both hands and both knees. At knee level, the prevalence was 2.7%, whereas at the wrist, we reported a prevalence of 4.9%.

CONCLUSIONS

The prevalence of CC for Mexican population had not been reported so far. This a starting point to break the silence and encourage the knowledge of how this disease is associated with possible risk factors in Mexican population. Key Points •The prevalence of chondrocalcinosis in Mexico was 3%. •The prevalence of knee chondrocalcinosis increases according to the age in women's. •The nixtamalized meals could be a protective factor for CC in Mexican population.

Association between chondrocalcinosis and osteoarthritis: A systematic review and meta-analysis

AIM

To systematically examine the existing literature on the associations between chondrocalcinosis (CC) and osteoarthritis (OA) at different joints, and to quantify such associations through meta-analysis.

METHODS

PubMed, Embase and Scopus databases were searched through from inception to June 2017. Cohort, case-control or cross-sectional studies were included if they examined the association between CC and OA. Data on the odds ratios (OR) and their 95% confidence intervals (CI) of the prevalence or progression of OA between the CC group and non-CC group with respect to the same joint were extracted.

RESULTS

A total of 14 studies were identified. Twelve studies were eligible for assessing the association between knee CC and knee OA. The combined data showed a positive association between them (OR = 2.84; 95% CI, 2.12-3.81; P < 0.001). Three studies were eligible for assessing the association between hip CC and hip OA. The data on the OR could only be extracted from one study (OR = 0.92; 95% CI, 0.68-1.24; P = 0.59). Two studies were eligible for assessing the association between hand CC and hand OA, and the data on the OR could only be extracted from one study which reported significant associations between CC and OA at the metacarpophalangeal joint (OR = 4.75; 95% CI, 2.12-10.64; P < 0.001) and the wrist joint (OR = 4.44; 95% CI, 3.56-5.54; P < 0.001).

CONCLUSION

This study established a strong association between knee CC and knee OA. However, the associations between CC and OA at the hip or hand still remain controversial and warrant further study.

Acute pseudogout – Measure serum magnesium

We report a 49-year-old woman with an acute swollen left knee due to acute pseudogout with chondrocalcinosis as a presenting feature of Gitelman syndrome due a novel homozygous mutation of the SLC12A3 gene. This report highlights the under-recognized importance of excluding metabolic disease, including Gitelman syndrome, in younger patients whose sole presenting feature may be chondrocalcinosis with or without pseudogout, as this may impact on management and risk of further episodes. We also suggest that chondrocalcinosis and hypomagnesaemia with or without hypokalaemia are diagnostic of Gitelman syndrome.

Current strategy in the treatment of calcium pyrophosphate crystal deposition disease

The paper considers currently available drugs used to treat calcium pyrophosphate crystal deposition disease. It discusses the advantages and disadvantages of the most widely used drugs, such as  nonsteroidal anti-inflammatory drugs, colchicine, glucocorticoids, traditional immunosuppressants, as well as prospects for the use of biologic agents.

Clinical Presentation, Management, and Prognosis of Pseudogout in Joint Arthroplasty: A Retrospective Cohort Study

Introduction: Calcium pyrophosphate deposition disease (CPPD), or pseudogout, is rare in prosthetic joints, but can mimic prosthetic joint infection (PJI) according to case reports. The purpose of this case series is to describe the demographics, presentation, management, and outcomes of a cohort of these patients seen at our academic medical center. Methods: Patients with post-implant pseudogout, who were evaluated at our medical center between January 1, 2000 and June 30, 2016, were identified from our EHR. Data pertaining to demographics, presentation, management, and outcomes were abstracted, and patients were categorized into two groups based on presence of concomitant infection along with positive CPDD findings in synovial fluid. Results: 22 patients were included. 90.9% of cases involved a TKA. The most common indication for arthroplasty was degenerative joint disease. Only four patients had a history of previous gout or pseudogout, three of which belonged to the group with no evidence of concomitant joint infection. Clinical features for patients without concomitant infection included pain (100%), swelling at the joint (88.9%), redness (33.3%), fever (22.2%), and decreased range of motion (100%). 45.5% of patients received antibiotics prior to joint aspiration (44.4% of patients with negative synovial fluid cultures, 46.2% of patients with concomitant infection). Conclusion: Our study suggests similar clinical presentation between post-implant pseudogout and PJI. Among patients with pseudogout as well as in those with PJI, the first dose of antibiotics should not be given before sampling for synovial culture. Unfortunately, many patients receive antibiotics prior to culture ascertainment, which raises concern for antibiotic overuse.

Age-Related Prevalence of Periodontoid Calcification and Its Associations with Acute Cervical Pain

STUDY DESIGN

Prospective study.

PURPOSE

To assess the prevalence of periodontoid calcification and its associations with acute cervical pain.

OVERVIEW OF LITERATURE

Calcium pyrophosphate dihydrate (CPPD) deposition disease is a common rheumatological disorder that occurs especially in elderly patients. Although CPPD crystals induce acute arthritis, these crystals are not usually symptomatic. Calcification surrounding the odontoid process (periodontoid calcification) has been reported to induce inflammation, resulting in acute neck pain. This disease is called crowned dens syndrome. Whether calcification induces inflammation or whether the crystals are symptomatic remains unclear.

METHODS

The prevalence of periodontoid calcification at the atlas transverse ligament was examined by computed tomography of the upper cervical spine in patients suspected of brain disease but no cervical pain (control group, n=296), patients with pseudogout of the peripheral joints but no cervical pain (arthritis group, n=41), and patients with acute neck pain (neck pain group, n=22). Next, the correlation between the prevalence of periodontoid calcification and symptoms was analyzed.

RESULTS

In the control group, 40 patients (13.5%) showed periodontoid calcification with no significant difference in the prevalence with gender. The prevalence of calcification increased significantly with age (p=0.002). In the arthritis group, 26 patients (63.4%) reported periodontoid calcification. In the neck pain group, 14 patients (63.6%) reported periodontoid calcification. Multiple logistic regression analysis by age and group revealed that higher age, inclusion in the arthritis group, and inclusion in the neck pain group significantly affected the prevalence of calcification.

CONCLUSIONS

Our results cumulatively suggest that periodontoid calcification is an aging-related reaction and that calcification per se does not always cause neck pain. Periodontoid calcification was observed more frequently in patients with pseudogout of the peripheral joints and in those with acute neck pain than in asymptomatic control patients.

Cartilage diseases

Hyaline cartilages, fibrocartilages and elastic cartilages play multiple roles in the human body including bearing loads in articular joints and intervertebral discs, providing joint lubrication, forming the external ears and nose, supporting the trachea, and forming the long bones during development and growth. The structure and organization of cartilage's extracellular matrix (ECM) are the primary determinants of normal function. Most diseases involving cartilage lead to dramatic changes in the ECM which can govern disease progression (e.g., in osteoarthritis), cause the main symptoms of the disease (e.g., dwarfism caused by genetically inherited mutations) or occur as collateral damage in pathological processes occurring in other nearby tissues (e.g., osteochondritis dissecans and inflammatory arthropathies). Challenges associated with cartilage diseases include poor understanding of the etiology and pathogenesis, delayed diagnoses due to the aneural nature of the tissue and drug delivery challenges due to the avascular nature of adult cartilages. This narrative review provides an overview of the clinical and pathological features as well as current treatment options available for various cartilage diseases. Late breaking advances are also described in the quest for development and delivery of effective disease modifying drugs for cartilage diseases including osteoarthritis, the most common form of arthritis that affects hundreds of millions of people worldwide.

Cartilage calcification of the ankle joint is associated with osteoarthritis in the general population

Background

Cartilage calcification (CC) is associated with osteoarthritis (OA) in weight-bearing joints, such as the hip and the knee. However, little is known about the impact of CC and degeneration on other weight-bearing joints, especially as it relates to the occurrence of OA in the ankles. The goal of this study is to analyse the prevalence of ankle joint cartilage calcification (AJ CC) and to determine its correlation with factors such as histological OA grade, age and BMI in the general population.

Methods

CC of the distal tibia and talus in 160 ankle joints obtained from 80 donors (mean age 62.4 years, 34 females, 46 males) was qualitatively and quantitatively analysed using high-resolution digital contact radiography (DCR). Correlations with factors, such as the joint’s histological OA grade (OARSI score), donor’s age and BMI, were investigated.

Results

The prevalence of AJ CC was 51.3% (95% CI [0.40, 0.63]), independent of gender (p = 0.18) and/or the joint’s side (p = 0.82). CC of the distal tibia was detected in 35.0% (28/80) (95% CI [0.25, 0.47]) and talar CC in 47.5% (38/80) (95% CI [0.36, 0.59]) of all cases. Significant correlations were noted between the mean amount of tibial and talar CC (r = 0.59, p = 0.002), as well as between the mean amount of CC observed in one ankle joint with that of the contralateral side (r = 0.52, p = 0.02). Furthermore, although the amount of AJ CC observed in the distal tibia and talus correlated with the histological OA-grade of the joint (r = 0.70, p < 0.001 and r = 0.72, p < 0.001, respectively), no such correlation was seen in the general population with relation to age (p = 0.32 and p = 0.49) or BMI (p = 0.51 and p = 0.87).

Conclusion

The prevalence of AJ CC in the general population is much higher than expected. The relationship between the amount of AJ CC and OA, independent of the donors’ age and BMI, indicates that CC may play a causative role in the development of OA in ankles.

Therapy for CPPD: Options and Evidence

PURPOSE OF REVIEW

Current evidence and accumulated experience for the management of calcium pyrophosphate deposition disease (CPPD) are presented.

RECENT FINDINGS

Contrary to other rheumatic inflammatory conditions that account for high interest and growing research, advances in treating CPPD are still very limited and mostly derive from those achieved in gout. Once formed, calcium pyrophosphate crystals cannot be dissolved; therefore, management relies on the control of crystal-derived inflammation. Besides classical agents-such as colchicine, glucocorticoids, or NSAIDs-the use of targeted therapies, mostly against interleukin-1, has provided a relevant relief for refractory CPPD patients in recent years. Meanwhile, former enthusiasm about conventional disease-modifying agents such as methotrexate is currently controversial.

Labral calcification in end-stage osteoarthritis of the hip correlates with pain and clinical function

The acetabular labrum of the hip (ALH) is recognized as a clinically important structure, but knowledge about the pathophysiology of this fibrocartilage is scarce. In this prospective study we determined the prevalence of ALH calcification in patients with end-stage osteoarthritis (OA) and analyzed the relationship of cartilage calcification (CC) with hip pain and clinical function. Cohort of 80 patients (70.2 ± 7.6years) with primary OA scheduled for total hip replacement. Harris Hip Score (HHS) was recorded preoperatively. Total ALH and femoral head (FH) were sampled intraoperatively. CC of the ALH and FH was analyzed by high-resolution digital contact radiography. Histological degeneration of the ALH (Krenn-Score) and FH (OARSI-Score) was determined. Multivariate linear regression model and partial correlation analyses were performed. The prevalence of cartilage calcification both in the ALH and FH was 100%, while the amount of CC in the ALH was 1.55 times higher than in the FH (p < 0.001). There was a significant inverse regression between the amount of calcification of both the ALH and the FH and preoperative HHS (β_ALH  = -2.1, p = 0.04), (β_FH  = -2.9, p = 0.005), but pain was influenced only by ALH calcification (β_ALH  = -2.7, p = 0.008). Age-adjusted, there was a significant correlation between cartilage calcification and histological degeneration (ALH:r_s  = 0.53, p < 0.001/FH: r_s  = 0.30, p = 0.007). Fibrocartilage and articular cartilage calcification are inseparable pathological findings in end-stage osteoarthritis of the hip. Fibrocartilage calcification is associated with poor and painful hip function.

CLINICAL SIGNIFICANCE

ALH fibrocartilage appears to be particularly prone to calcification, which may explain higher pain levels in individuals with a high degree of ALH calcification independent of age and histological degeneration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1248-1255, 2018.

Concurrence of rheumatoid arthritis and calcium pyrophosphate deposition disease: A case collection and review of the literature

OBJECTIVE

Calcium pyrophosphate deposition disease (CPDD) is arthritis caused by calcium pyrophosphate (CPP) crystal deposition in joints. It is commonly associated with aging as well as a handful of metabolic syndromes. Recent epidemiologic studies suggest a positive association of CPDD and rheumatoid arthritis (RA). Yet how these diseases are related remains unclear. We set out to describe 21 well-characterized patients with both diagnoses.

METHODS

Medical records of patients with both RA and CPDD identified at a single academic practice site were reviewed for age, gender, age of CPDD and RA onset, disease duration, joint involvement, and lab values including rheumatoid factor (RF), cyclic citrullinated peptide antibody (CCP), iron studies, and parathyroid hormone and calcium levels.

RESULTS

The mean age of CPDD onset was 69.5 ± 11.4 years, with a mean RA age onset of 53.9 ± 16 years, demonstrating a mean lag of 13.4 ± 10.9 years between diagnoses. The majority of RA patients were diagnosed with CPDD based on the presence of radiographic chondrocalcinosis (15/21). The most commonly involved joint was the knee, followed by the wrist, hip, and shoulder.

CONCLUSIONS

These data show that the diagnosis of RA often precedes the diagnosis of CPDD. This asynchronous presentation taken together with the classic age of onset for CPDD and typical pattern of joint involvement supports the hypothesis that CPDD develops in RA patients through similar processes as those that cause the idiopathic forms of this disease.

Age-related changes in the knee meniscus

BACKGROUND

Aging is the most prominent risk factor for the development of osteoarthritis (OA), which affects knees and causes major health burdens. Meniscal dysfunction mostly based on degeneration contributes to the development and progression of knee OA. Meniscal degeneration is caused by various extrinsic factors, such as repetitive trauma or leg malalignment, while meniscal aging is considered as internal changes, such as molecular or cellular changes. Little is known about age-related changes in the meniscus. Therefore, this review aimed to summarize and clarify the understanding of the aged meniscus.

METHODS

There are few articles about natural aging in the meniscus, because most reports only demonstrate the effects of OA on the meniscus. We searched PubMed (1948 to November 2016) to identify and summarize all English-language articles evaluating natural aging in the meniscus.

RESULTS

There is evidence of compositional change in the meniscus with aging, involving cells, collagens, and proteoglycans. In addition, as recent reports on the natural aging of cartilage have indicated, senescence of the meniscal cells may also lead to disruption of meniscal cells and tissue homeostasis. Due to the low turnover rate of collagen, accumulation of advanced glycation end-products largely contributes to tissue stiffness and vulnerability, and finally results in degenerative changes or tears. Furthermore, environmental factors such as joint fluid secreted by inflamed synovium could also contribute to meniscal tissue deterioration.

CONCLUSIONS

Age-related changes induce meniscal tissue vulnerability and finally lead to meniscal dysfunction.

Dose-response relationship between lower serum magnesium level and higher prevalence of knee chondrocalcinosis

Background

The aim was to assess serum magnesium levels in relation to prevalence of knee chondrocalcinosis in two population-based Chinese studies.

Methods

Data included in this analysis consisted of two population-based cross-sectional studies, i.e., the Xiangya Hospital Health Management Center Study and the Xiangya Osteoarthritis (XO) Study I. A bilateral knee anteroposterior radiograph was obtained from each subject. Radiographic knee chondrocalcinosis was present if there was definite linear cartilage calcification. Serum magnesium concentration was measured using the chemiluminescence method. We examined the relation of serum magnesium levels to prevalence of knee chondrocalcinosis using generalized estimating equations.

Results

The prevalence of knee chondrocalcinosis was 1.4% in the Xiangya Hospital Health Management Center Study (n = 12,631). Compared with the lowest tertile, the age, sex and body mass index (BMI)-adjusted odds ratios (ORs) of chondrocalcinosis were 0.59 (95% CI 0.40–0.87) and 0.49 (95% CI 0.33–0.72) in the second and the third tertiles of serum magnesium, respectively (P for trend <0.001). The prevalence of knee chondrocalcinosis in the XO Study I (n = 1316) was 4.1%. The age, sex and BMI-adjusted ORs of chondrocalcinosis were 0.67 (95% CI 0.34–1.30) in the second and 0.45 (95% CI 0.21–0.94) in the third tertile of serum magnesium when compared with the lowest tertile (P for trend = 0.030). Similar results were observed in men and women in both studies. Adjusting for additional potential confounders did not change the results materially.

Conclusions

Subjects with lower levels of serum magnesium, even within the normal range, had higher prevalence of knee chondrocalcinosis in a dose-response relationship manner, suggesting that magnesium may have a preventive or therapeutic potential for knee chondrocalcinosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1450-6) contains supplementary material, which is available to authorized users.

Association of Chondrocalcinosis in Knee Joints With Pain and Synovitis: Data From the Osteoarthritis Initiative

OBJECTIVE

To evaluate the relationship between chondrocalcinosis and pain or synovitis in knee joints by examining data from the Osteoarthritis Initiative (OAI).

METHODS

Data were obtained from the OAI public-use data sets. The relationship between chondrocalcinosis on baseline knee radiograph and pain at baseline and at 4 years was examined. Analyses were adjusted for age, sex, body mass index, and Kellgren-Lawrence (K/L) grade and the correlation between 2 knees in a subject was controlled using generalized estimating equations. The relationship between chondrocalcinosis and synovitis on magnetic resonance imaging (MRI) was examined by comparing knees with chondrocalcinosis at baseline and age, sex, and K/L grade-matched knees with no chondrocalcinosis. We read MRIs of a subset of knees for synovitis using the MRI Osteoarthritis Knee Score (MOAKS) on baseline and 4-year MRI.

RESULTS

Knees with chondrocalcinosis (n = 162) more often had pain compared to knees without chondrocalcinosis (n = 2,030) at baseline and had higher Western Ontario and McMaster Universities Osteoarthritis Index pain scores, both at baseline (mean 2.4 [95% confidence interval (95% CI) 1.9, 2.9]) versus mean 1.8 [95% CI 1.7, 1.9]) and at 4 years (mean 2.5 [95% CI 1.9, 3.1] versus mean 1.6 [95% CI 1.5, 1.8]), as well as higher Intermittent and Constant Osteoarthritis Pain intermittent pain scores at 4 years. There was no difference in MOAKS synovitis scores at baseline and at 4 years between the chondrocalcinosis group (n = 102) and the control group (n = 99).

CONCLUSION

Knees with chondrocalcinosis had increased pain and did not have higher synovitis scores on MRI compared to knees without chondrocalcinosis. The mechanisms by which chondrocalcinosis is associated with increased pain remain to be determined.

Calcium Pyrophosphate Deposition Disease and Associated Medical Comorbidities: A National Cross-Sectional Study of US Veterans

OBJECTIVE

Calcium pyrophosphate deposition disease (CPDD) is a common cause of acute and chronic arthritis, yet there are few large epidemiologic studies of CPDD. We sought to characterize CPDD in the national Veterans Affairs (VA) population.

METHODS

Using data from the Department of VA Corporate Data Warehouse, patients with International Classification of Diseases, Ninth Revision, codes for CPDD seen at any VA medical center from 2010 through 2014 were matched by age and sex with control patients without CPDD. We used multivariate analysis to compare the prevalence and odds ratios (ORs) of various comorbidities, substance use, medication exposures, and arthroplasties among patients with and without CPDD.

RESULTS

We identified 25,157 patients with CPDD, yielding a point prevalence of 5.2 per 1,000. The mean ± SD age was 68.1 ± 12.3 years, and 95% were male. The strongest positive associations with CPDD were hyperparathyroidism (OR 3.35 [95% confidence interval (95% CI) 2.96-3.79]), gout (OR 2.82 [95% CI 2.69-2.95]), osteoarthritis (OR 2.26 [95% CI 2.15-2.37]), rheumatoid arthritis (OR 1.88 [95% CI 1.74-2.03]), and hemochromatosis (OR 1.87 [95% CI 1.57-2.24]). Positive associations were also seen with higher odds for osteoporosis (OR 1.26 [95% CI 1.16-1.36]), hypomagnesemia (OR 1.23 [95% CI 1.16-1.30]), chronic kidney disease (OR 1.12 [95% CI 1.07-1.18]), and calcium supplementation (OR 1.15 [95% CI 1.06-1.24). Negative associations were seen with proton-pump inhibitors (OR 0.58 [95% CI 0.55-0.60]) and loop diuretics (OR 0.80 [95% CI 0.76-0.84]).

CONCLUSION

Using a large national data set, we confirmed known associations with CPDD, provided support for positive associations with rheumatoid arthritis, hypomagnesemia, and osteoporosis, and suggested potential novel negative associations with commonly used medications.

Prevalence of Chondrocalcinosis in Patients above 50 Years and the Relationship with Osteoarthritis

BACKGROUND

Some studies showed a relation between chondrocalcinosis and osteoarthritis (OA). Hence, considering the importance of chondrocalcinosis diagnosis andnecessity for its integration with OA, the current study aims at investigating prevalence of chondrocalcinosis in patients above 50 years admitted to Isfahan Al-Zahra Medical Center and its relationship with OA.

MATERIALS AND METHODS

In a cross-sectional study, 600 patients who referred to the radiology units of Al-Zahra Hospital for radiography of different joints were studied during 2013-2014. The patients images were studied for chondrocalcinosis and OA by a radiologist and also examined clinically and results of imaging by an expert rheumatologist. The prevalence of chondrocalcinosis and it relation with OA was determined by Statistical Package for Social Sciences software and using of Chi-square and t-test.

RESULTS

23 patients under study had chondrocalcinosis (3.83%). patients with chondrocalcinosis had higher age average, and they were in age group of 70 years and older, but no significant difference was observed regarding the prevalence of the disease in both genders. Chondrocalcinosis prevalence in terms of body mass index showed significant differences (P = 0.001). All patients with chondrocalcinosis had a history of joint disease and prevalence of chondrocalcinosis in terms of joint disease history showed a significant difference (P < 0.001).

CONCLUSION

Prevalence of chondrocalcinosis is relatively high in the Iranian population of 70 years and older. Hence, more investigation considering to the diagnosis of chondrocalcinosis among patients with OA is very important.

Conventional Radiology in Crystal Arthritis: Gout, Calcium Pyrophosphate Deposition, and Basic Calcium Phosphate Crystals

This article reviews the main radiographic features of crystal deposition diseases. Gout is linked to monosodium urate crystals. Classic radiographic features include subcutaneous tophi, large and well-circumscribed paraarticular bone erosions, and exuberant bone hyperostosis. Calcium pyrophosphate deposition (CPPD) can involve numerous structures, such as hyaline cartilages, fibrocartilages, or tendons. CPPD arthropathy involves joints usually spared by osteoarthritis. Basic calcium phosphate deposits are periarticular or intraarticular. Periarticular calcifications are amorphous, dense, and round or oval with well-limited borders, and most are asymptomatic. When resorbing, they become cloudy and less dense with an ill-defined shape and can migrate into adjacent structures.

Low prevalence of knee chondrocalcinosis and its catabolic association with serum matrix metalloproteinase 3: A rural Japanese population study

AIM

This study aimed to elucidate the prevalence of radiographic knee chondrocalcinosis (CC) and to clarify whether CC is correlated with self-reported knee symptoms and a serum catabolic biomarker.

METHODS

A total of 1278 volunteers participated. Plain radiographs of both knees were obtained. Identification of a linear calcification in the knee joint space was defined as CC. Patients with a Kellgren-Lawrence grade of 2 or more were considered to have knee osteoarthritis (OA). Symptoms were evaluated using the Knee injury and Osteoarthritis Outcome Score (KOOS) Pain scale, and serum matrix metalloproteinase-3 (MMP-3) concentration was determined. Multiple regression analysis was conducted to determine whether CC was correlated with OA, the KOOS Pain scale and MMP-3 concentration.

RESULTS

Twenty-eight subjects were found to have CC (2.2%), and 389 had OA (30.4%). CC was correlated with OA (odds ratio: 5.797; P = 0.006). Additionally, CC was correlated with MMP-3 concentration (B = 11.415, β = 0.059, P = 0.014), but not with KOOS Pain scale.

CONCLUSIONS

The prevalence of CC was low in the Japanese population evaluated in this study. While CC was not correlated with self-reported knee symptoms, it was positively correlated with serum MMP-3 concentration.

Incident acute pseudogout and prior bisphosphonate use: Matched case-control study in the UK-Clinical Practice Research Datalink

Oral bisphosphonates are the most commonly used drugs to treat postmenopausal osteoporosis. Acute pseudogout is anecdotally reported to occur following bisphosphonate initiation but empirical data are lacking. We investigated whether treatment with oral bisphosphonates is a risk factor for incident acute pseudogout.A matched case-control study was undertaken using data from the UK-Clinical Practice Research Datalink. Adults who consulted for incident acute pseudogout between 1987 and 2012 were each matched for gender, age at pseudogout diagnosis, and general practice to up to 4 control subjects without pseudogout. The exposure of interest was a prescription for an oral bisphosphonate issued within the 60-day period prior to the date of incident acute pseudogout. Associations between incident acute pseudogout and prior bisphosphonate prescription were examined using conditional logistic regression, adjusting for hyperparathyroidism, osteoarthritis, rheumatoid arthritis, hemochromatosis, hypophosphatasia, and prescriptions for diuretics and oral corticosteroids.Two thousand eleven acute pseudogout cases were compared with 8013 matched controls without acute pseudogout (mean age [standard deviation] 72 years [14]; 52% male). One hundred twenty-three cases (6.1%) had received an oral bisphosphonate prescription in the 60-day exposure period compared with 305 controls (3.8%) (adjusted incidence rate ratio [IRR] 1.33; 95% confidence interval [CI] 1.05-1.69). This association was stronger in females (adjusted IRR 1.49; 95% CI 1.15-1.94) and was nonsignificant in males (0.83; 0.48-1.44).Incident acute pseudogout was associated with prescription of an oral bisphosphonate in the preceding 60 days. Prescribers should be aware of acute pseudogout as a possible side effect of bisphosphonate treatment. Further research is needed to explore the risks conferred by different bisphosphonates and the mechanism underlying this association.

Calcium pyrophosphate deposition disease: a review of epidemiologic findings

PURPOSE OF REVIEW

The purpose of this review is to summarize the recent advances in the epidemiology of calcium pyrophosphate deposition disease (CPPD), and to discuss their implications. This review is particularly timely as several epidemiological studies that enhance the understanding of CPPD have been published recently.

RECENT FINDINGS

This article will review recent findings on the prevalence of chondrocalcinosis; discuss new data on the associations between bone mineral density and chondrocalcinosis; and between diuretic use, chronic kidney disease 5 and 'pseudogout' (now termed acute calcium pyrophosphate crystal arthritis). It will summarize findings from a large dataset which reported that chondrocalcinosis results from a systemic predisposition, and that the association between chondrocalcinosis and polymorphisms in ANKH gene is independent of age and osteoarthritis. It will also review recent data which suggest that the association between chondrocalcinosis and osteoarthritis may be joint specific, and that chondrocalcinosis associates with radiographic attrition in knees with osteoarthritis.

SUMMARY

The studies reviewed suggest that CPPD occurs due to a generalized predisposition, and that it modifies the radiographic phenotype of osteoarthritis. However, further research is required to confirm if CPPD modifies the clinical phenotype of osteoarthritis.

Current advances in therapies for calcium pyrophosphate crystal arthritis

PURPOSE OF REVIEW

Calcium pyrophosphate (CPP) crystal disease is a common rheumatologic disorder that has received limited attention from the scientific community. This review is aimed at summarizing current evidence for managing CPP disease (CPPD), focusing on recently reported advances.

RECENT FINDINGS

New data from case series indicate that interleukin-1β inhibitors can help patients with refractory forms of CPPD. Methotrexate, formerly a promising agent, failed to demonstrate benefits in a recent trial, but still merits consideration for some patients. No significant advances on crystal dissolution have been achieved to date. Proper characterization of the CPP crystal disease picture is needed, ruling out the possible coexistence of another persistent arthritis unrelated to the CPP deposition.

SUMMARY

Advances on CPP crystal dissolution and establishing definitions of the clinical spectrum of CPPD remain the main challenges for CPP crystal disease management.

First cases of calcium pyrophosphate deposition disease after zoledronic acid therapy

A number of medications promote the development of calcium pyrophosphate deposition disease (CPDD). We report 2 cases of acute CPDD after intravenous zoledronic acid therapy. Case #1: a 63-year-old female was admitted for vertebroplasty at the site of an osteoporotic fracture. She received an intravenous infusion of zoledronic acid 5mg on the day after the procedure. Acute CPDD developed in her right knee 24hours later. Findings from joint aspiration and standard radiography confirmed the diagnosis. Case #2: this 79-year-old woman had a history of CPDD was on glucocorticoid and hydroxychloroquine therapy for lupus. She was given an intravenous infusion of zoledronic acid 5mg as prophylaxis of glucocorticoid-induced osteoporosis. Joint pain and a fever developed later on the same day. After 5 days, she had arthritis of the right wrist, laboratory evidence of systemic inflammation, and hypocalcemia. Radiographs showed evidence of CPDD. A Medline search identified 6 cases of bisphosphonate-related CPDD, including 2 due to pamidronate, 2 to etidronate, 1 to alendronic acid, and 1 to neridronic acid. The features were similar to those in our patients, with a short time to onset, systemic inflammation in many cases, a tendency toward hypocalcemia, and radiographs that often showed evidence of CPDD. Bisphosphonate-induced CPDD is a rare eventuality that should nevertheless be borne in mind by rheumatologists. Also, in patients with CPDD while taking bisphosphonate therapy, a role for the drug in the symptoms should be considered.

Articular cartilage calcification of the hip and knee is highly prevalent, independent of age but associated with histological osteoarthritis: evidence for a systemic disorder

OBJECTIVES

Based on the concept of a systemic predisposition for articular cartilage calcification (CC), the aim of this study was to determine the prevalence and amount of bilateral CC of hip and knee joints in an unselected sample cohort by high-resolution digital contact radiography (DCR) and to analyze the association of CC with histological OA.

METHODS

Both hip and knee joints of 87 donors (48 m and 39 f; mean age 62) were analyzed by DCR in this post-mortem study of an unselected cohort of donors. Histological OA (OARSI) of the main load bearing area of femoral heads and medial femoral condyles was determined.

RESULTS

The prevalence of CC of the femoral head was 96.6%, of the knee 94.3%. Bilateral calcification was detected in 79.3% of hips and 86.2% of knees. Concomitant CC of all four joints was detected in 69.0% of donors. There was no difference between the amount of CC of hips and knees (P = 0.47). The amount of CC of any given hip or knee correlated with that of the contralateral hip (r_s = 0.54, P < 0.001) or knee (r_s = 0.50, P < 0.001). There was a correlation between the amount of CC and histological OA (hips r_s = 0.48, P < 0.001, knees r_s = 0.30, P = 0.004), but not between CC and age (hips r_s = -0.09, P = 0.42; knees r_s = 0.10, P = 0.34).

CONCLUSIONS

These data support the concept that articular CC occurs as the result of a systemic disorder. CC appears to be an early element of hip and knee OA pathogenesis independent of age.

Hyaline cartilage calcification of the first metatarsophalangeal joint is associated with osteoarthritis but independent of age and BMI

Background

Hyaline cartilage calcification (CC) is associated with osteoarthritis (OA) in hip and knee joints. The first metatarsophalangeal joint (1^stMTPJ) is frequently affected by OA, but it is unclear if CC occurs in the 1^stMTPJ. The aim of the present study was to analyze the prevalence of CC of the 1^stMTPJ in the general population by high-resolution digital contact radiography (DCR) and to determine its association with histological OA severity, age and body mass index (BMI).

Methods

168 metatarsal heads of 84 donors (n = 47 male, n = 37 female; mean age 62.73 years, SD ±18.8, range 20–93) were analyzed by DCR for the presence of CC. Histological OA grade (hOA) by OARSI was analyzed in the central load-bearing zone of the first metatarsal head (1^st MH). Structural equation modeling (SEM) was performed to analyze the interrelationship between CC, hOA, age and BMI.

Results

The prevalence of CC of 1^stMH was 48.8 % (41/84) (95 %-CI [37.7 %, 60.0 %]), independent of the affected side (p = 0.42), gender (p = 0.41) and BMI (p = 0.51). The mean amount of CC of one MH correlated significantly with that of the contralateral side (r_s = 0.4, 95 %-CI [0.26, 0.52], p < 0.001). The mean amount of CC (in % of total cartilage area) of the MH correlated significantly with the severity of hOA (r_s = 0.51, 95 %-CI [0.32, 0.65], p < 0.001). SEM revealed significant associations between CC and hOA (r = 0.74, p < 0.001) and between hOA and age (β = 0.62, p = 0.001), but not between CC and age (p = 0.15). There was no significant influence of BMI on either CC (p = 0.37) or hOA (p = 0.16).

Conclusion

The observation that CC of the 1^stMH is significantly associated with the severity of OA but independent of age and BMI, suggests an intimate relationship between CC and the pathogenesis of OA, the exact nature of which will have to be explored by future studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1324-0) contains supplementary material, which is available to authorized users.

Articular cartilage calcification of the humeral head is highly prevalent and associated with osteoarthritis in the general population

Articular cartilage calcification is considered a pathological albeit incompletely understood process which is known to be associated with osteoarthritis of the knee and hip. The goal of this study was to determine the prevalence of articular cartilage calcification of the shoulder as a non-weight-bearing joint and to analyze the interrelationship of calcification with age and histological severity of shoulder osteoarthritis in the general population. In a cross-sectional study of 180 humeral heads from 90 donors (n = 49 male, n = 41 female; mean age 62.7 years [20-93]), cartilage calcification of the humeral head was quantified by digital contact radiography (DCR). Histological OA grade (OARSI) was determined and structural equation modeling (SEM) was used to analyze the interrelationship of cartilage calcification, OARSI and age. The prevalence of articular cartilage calcification was 98.9% (95%CI: [93.96%, 99.97%]) and was independent of gender (p = 0.55). Cartilage calcification of one shoulder correlated significantly with that of the contralateral side (r = 0.61, 95%CI: [0.46, 0.73], p < 0.001). SEM demonstrated significant associations between histological OA grade and cartilage calcification (r = 0.55, p = 0.039), between histological OA grade and age (β = 0.59, p < 0.001) but not between age and cartilage calcification (β = 0.24, p = 0.116). In conclusion, the prevalence of shoulder cartilage calcification in the general population is higher than anticipated. The high prevalence, its concomitant bilateral manifestation and the association between the amount of cartilage calcification and OA severity, but not age, suggest that cartilage calcification is a systemically driven process with early onset in life and may be a causative factor in the pathogenesis of OA. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1984-1990, 2016.

Atypical Tumoral Presentation of Calcium Pyrophosphate Deposition Disease: A Case Report

CASE

A 55-year-old man presented with a history of forefoot pain and swelling. Radiographs revealed a mass with internal calcifications and osseous erosion of the fifth metatarsophalangeal bone. The mass was isointense to muscle on T1-weighted magnetic resonance imaging (MRI) and hyperintense on T2-weighted MRI. A biopsy was performed, and intraoperatively, the lesion appeared as chalky white material, which under polarized light microscopy was composed of weakly positively birefringent rhomboid crystals, leading to a diagnosis of tophaceous pseudogout.

CONCLUSION

Tophaceus pseudogout should be included in the differential diagnosis of neoplastic-appearing lesions in the foot, and polarized light microscopy should be used when examining biopsy specimens.

High-Resolution US of Rheumatologic Diseases

For the past 15 years, high-resolution ultrasonography (US) is being routinely and increasingly used for initial evaluation and treatment follow-up of rheumatologic diseases. This imaging technique is performed by using high-frequency linear transducers and has proved to be a powerful diagnostic tool in evaluation of articular erosions, simple and complex joint and bursal effusions, tendon sheath effusions, and synovitis, with results comparable to those of magnetic resonance imaging, excluding detection of bone marrow edema. Crystal deposition diseases including gouty arthropathy and calcium pyrophosphate deposition disease (CPPD) have characteristic appearances at US, enabling differentiation between these two diseases and from inflammatory arthropathies. Enthesopathy, which frequently accompanies psoriatic and reactive arthritis, also has a characteristic appearance at high-resolution US, distinguishing these two entities from other inflammatory and metabolic arthropathies. The presence of Doppler signal in examined joints, bursae, and tendon sheaths indicates active synovitis. Microbubble echo contrast agents augment detection of tissue vascularity and may act in the future as a drug delivery vehicle. Frequently, joint, tendon sheath, and bursal fluid aspirations and therapeutic injections are performed under US guidance. The authors describe the high-resolution US technique including gray-scale, color or power Doppler, and contrast agent-enhanced US that is used in evaluation of rheumatologic diseases of the wrist and hand and the ankle and foot in their routine clinical practice. This article demonstrates imaging findings of normal joints, rheumatoid arthritis, gouty arthritis, CPPD, psoriatic and reactive arthritis, and osteoarthritis.

Prevalence of asymptomatic chondrocalcinosis in the pelvis

OBJECTIVE

To determine trends in incidentally detected age- and gender-associated chondrocalcinosis on pelvic CT.

MATERIALS AND METHODS

Twenty patients of each gender at the center of each decade of life who underwent a CT scan of the pelvis performed 2009-2013 were identified and selected for a total of 400 pelvic CTs. Images were reviewed independently by two radiologists for the presence or absence of chondrocalcinosis within the pelvis. Patients with hip or low back pain, known CPPD arthropathy or any known predisposing condition, prior hip arthroplasty, or articular fracture were excluded. Logistic regression was used to predict the presence/absence of chondrocalcinosis as a function of patient age and gender.

RESULTS

The presence/absence of chondrocalcinosis was found to be associated with patient age (p = 0.016) but not patient gender (p = 0.929). In the pelvis, chondrocalcinosis was most frequently identified at the pubic symphysis. Incidental chondrocalcinosis was not identified in any patients under 50 years of age. Chondrocalcinosis increased in frequency from 12.5 at 55 years of age to 27.5 % of patients 95 years of age.

CONCLUSIONS

Chondrocalcinosis is common and more prevalent in late adulthood, occurs without a gender predilection, and is infrequently identified in patients younger than 50 years of age.

Validation of administrative codes for calcium pyrophosphate deposition: a Veterans Administration study

BACKGROUND

Despite high prevalence, progress in calcium pyrophosphate deposition (CPPD) has been limited by poor awareness and absence of validated approaches to study it in large data sets.

OBJECTIVES

We aimed to determine the accuracy of administrative codes for the diagnosis of CPPD as a foundational step for future studies.

METHODS

We identified all patients with an International Classification of Diseases, Ninth Revision, Clinical Modification code for chondrocalcinosis (712.1-712.39) or pseudogout/other disorders of mineral metabolism (275.49), and convenience sample selected a comparison group with gout (274.00-03 or 274.8-9), or rheumatoid arthritis (714.0) from 2009 to 2011 at a Veterans Affairs medical center. Each patient was categorized as having definite, probable, or possible CPPD or absence of CPPD based on the McCarty and Ryan criteria using chart abstracted data including crystal analysis, radiographs, and arthritis history.

RESULTS

Two hundred forty-nine patients met the clinical gold standard criteria for CPPD based on medical records, whereas 48 patients met definite criteria, 183 probable, and 18 met possible criteria. The accuracy of administrative claims with a code of 712 or 275.49 for definite or probable CPPD was as follows: 98% sensitivity (95% confidence interval, 96%-99%), 78% specificity (74%-83%), 91% positive predictive value, and 94% negative predictive value.

CONCLUSIONS

At this center, single administrative code 275.49 or 712 accurately identifies patients with CPPD with a positive predictive value of 91%. These findings suggest that administrative codes can have strong clinical accuracy and merit further validation to allow adoption in future epidemiologic studies of CPPD.

The role of peripheral nerve fibers and their neurotransmitters in cartilage and bone physiology and pathophysiology

The peripheral nervous system is critically involved in bone metabolism, osteogenesis, and bone remodeling. Nerve fibers of sympathetic and sensory origin innervate synovial tissue and subchondral bone of diathrodial joints. They modulate vascularization and matrix differentiation during endochondral ossification in embryonic limb development, indicating a distinct role in skeletal growth and limb regeneration processes. In pathophysiological situations, the innervation pattern of sympathetic and sensory nerve fibers is altered in adult joint tissues and bone. Various resident cell types of the musculoskeletal system express receptors for sensory and sympathetic neurotransmitters. Osteoblasts, osteoclasts, mesenchymal stem cells, synovial fibroblasts, and different types of chondrocytes produce distinct subtypes of adrenoceptors, receptors for vasointestinal peptide, for substance P and calcitonin gene-related peptide. Many of these cells even synthesize neuropeptides such as substance P and calcitonin gene-related peptide and are positive for tyrosine-hydroxylase, the rate-limiting enzyme for biosynthesis of catecholamines. Sensory and sympathetic neurotransmitters modulate osteo-chondrogenic differentiation of mesenchymal progenitor cells during endochondral ossification in limb development. In adults, sensory and sympathetic neurotransmitters are critical for bone regeneration after fracture and are involved in the pathology of inflammatory diseases as rheumatoid arthritis which manifests mainly in joints. Possibly, they might also play a role in pathogenesis of degenerative joint disorders, such as osteoarthritis. All together, accumulating data imply that sensory and sympathetic neurotransmitters have crucial trophic effects which are critical for proper limb formation during embryonic skeletal growth. In adults, they modulate bone regeneration, bone remodeling, and articular cartilage homeostasis in addition to their classic neurological actions.

Genetic loci that regulate ectopic calcification in response to knee trauma in LG/J by SM/J advanced intercross mice

This study reports on genetic susceptibility to ectopic calcification in the LG/J and SM/J advanced intercross mice. Using 347 mice in 98 full-sibships, destabilization of medial meniscus (DMM) was performed to induce joint injury. We found that joint destabilization instigated ectopic calcifications as detected and quantified by micro-CT. We performed quantitative trait locus (QTL) analysis to map ectopic calcification phenotypes to discrete genomic locations. To validate the functional significance of the selected QTL candidate genes, we compared mRNA expression between parental LG/J and SM/J inbred strains. Overall, we detected 20 QTLs affecting synovial and meniscus calcification phenotypes with 11 QTLs linked to synovial calcification. Functional and bioinformatic analyses of single nucleotide polymorphism (SNP) identified functional classifications relevant to angiogenesis (Myo1e, Kif26b, Nprl3, Stab2, Fam105b), bone metabolism/calcification (Tle3, Tgfb2, Lipc, Nfe2l1, Ank, Fam105b), arthritis (Stab2, Tbx21, Map4k4, Hoxb9, Larp6, Col1a2, Adam10, Timp3, Nfe2l1, Trpm3), and ankylosing-spondylitis (Ank, Pon1, Il1r2, Tbkbp1) indicating that ectopic calcification involves multiple mechanisms. Furthermore, the expression of 11 out of 78 candidate genes was significantly different between LG/J and SM/J. Correlation analysis showed that Aff3, Fam81a, Syn3, and Ank were correlated with synovial calcification. Taken together, our findings of multiple genetic loci suggest the involvement of multiple genes contributing to ectopic calcification.

Erosive osteoarthritis, psoriatic arthritis and pseudogout; a casual association?

According to recent hypothesis, the inflammation has a pivotal role in the onset and progression of erosive hand osteoarthritis (EHOA), psoriatic arthritis (PsA) and chondrocalcinosis (CC)/pseudogout. Albeit, it has been recognised for years as an association between EHOA and radiographic evidence of CC, but there are few reports of coexistence of microcrystalline arthritis and PsA. This is the first report that described a clinical experience concerning two consecutive cases of patients presented with EHOA, PsA and pseudogout. Two Caucasian women of 71 and 85 years old with a history of OA and mild psoriasis are presented with tenderness and swelling of first interphalangeal (IP) and wrist joint, respectively. Arthrocentesis performed at the first IP and wrist joint, respectively, showed an inflammatory synovial fluid with presence of calcium pyrophosphate dehydrate crystals. X-rays of hands, feet and knees showed characteristic features of EHOA, PsA and CC. Furthermore, HLA typing evinces the presence of HLA C*06; DRB*01 07 and HLA C*07; DRB*01 *11 alleles, respectively, predisposing factors of these inflammatory diseases. The relationship between these aggressive rheumatic diseases along with their clinical, radiographic, laboratory and genetic features is discussed.

Methotrexate: should it still be considered for chronic calcium pyrophosphate crystal disease?

Chronic calcium pyrophosphate crystal arthritis is a clinical consequence of the formation and deposition of these crystals in joints and can result in persistent arthritis. Curative treatment would require the removal of crystals from joints and tissues, but to date all agents tested have proven ineffective. Management of the inflammatory manifestations of chronic calcium pyrophosphate disease includes glucocorticoids, non-steroidal anti-inflammatory drugs, or colchicine, and responses are usually satisfactory. However, in some patients, the response to these agents is poor or they are contraindicated. Methotrexate had been reported as a promising option in small case series; however, in a recent issue of Arthritis Research & Therapy, a clinical trial failed to confirm the anticipated benefits. Here, we discuss some issues that might have influenced the results of the study, before deciding to abandon methotrexate as a therapeutic option for patients with chronic calcium pyrophosphate arthritis.

Destructive pseudo-neuroarthropathy associated with calcium pyrophosphate deposition

BACKGROUND

Calcium pyrophosphate deposition (CPPD) disease is a metabolic disorder characterized by soft tissue calcific deposits formed primarily in articular cartilage. What can result is a crystal-induced arthropathy often referred to as pseudogout, which is variable in both presentation and severity. A particularly destructive and deforming arthritis is an uncommon but well-recognized subtype of this disease. Radiologically resembling the neuroarthropathy described by Charcot, a pattern of joint fragmentation and structural collapse occurs in the absence of peripheral neuropathy. This pseudo-neuroarthropathy is rarely reported in the foot and ankle.

METHODS

A total of 15 cases of pseudo-neuroarthropathy involving some previously unreported joints within the foot and ankle are described in this case series of 9 patients.

RESULTS

All patients presented with disease involving multiple joints. Clinical deformity was apparent in each case, and extensive joint destruction was seen on plain radiographs. In 6 patients, histopathological CPPD disease was confirmed on tissue biopsy of the affected joints. In the remaining 3 patients a clinical diagnosis was made on the basis of the classic appearance of pseudo-neuroarthropathy in the foot, with additional recognized features of CPPD. Operative management with deformity correction using joint arthrodesis produced satisfactory clinical and radiological results.

CONCLUSIONS

In the absence of peripheral neuropathy and systemic disease, the pseudo-neuroarthropathy of CPPD should be considered when a progressively deforming and destructive arthritis is seen in the foot and ankle.

LEVEL OF EVIDENCE

Level IV, case series.