Hydroxyapatite crystal deposition causing rapidly destructive arthropathy of the hip joint

De novo vesico-acetabular fistula presenting with septic arthritis: Case report and literature review

Vesico-acetabular fistula formation is a rare condition typically associated with total hip arthroplasty. Clinical features can include pain of the hip and flank, haematuria, and dysuria. We report the case of a 67-year-old female with a past medical history of bilateral pelvic fractures and calcium hydroxyapatite deposition disease of the hip joint, who developed vesico-acetabular fistula in the absence of surgery. This was then complicated by septic arthritis. We highlight the ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) findings of the case and review the previous case reports describing the vesico-acetabular fistula.

High frequency of BCP, but less CPP crystal-mediated calcification in cartilage and synovial membrane of osteoarthritis patients

OBJECTIVE

Ectopic articular calcification is a common phenomenon of osteoarthritic joints, and closely related to disease progression. Identification of the involved calcium crystal types represents an important topic in research and clinical practice. Difficulties in accurate detection and crystal type identification have led to inconsistent data on the prevalence and spatial distribution of Basic calcium phosphate (BCP) and calcium pyrophosphate (CPP) deposition.

METHOD

Combining multiple imaging methods including conventional radiography, histology and Raman spectroscopy, this study provides a comprehensive analysis of BCP and CPP-based calcification, its frequency and distribution in cartilage and synovial membrane samples of 92 osteoarthritis patients undergoing knee replacement surgery.

RESULTS

Conventional radiography showed calcifications in 35% of patients. Von Kossa staining detected calcified deposits in 88% and 57% of cartilage and synovial samples, respectively. BCP crystals presented as brittle deposits on top of the cartilage surface or embedded in synovial tissue. CPP deposits appeared as larger granular needle-shaped clusters or dense circular pockets below the cartilage surface or within synovial tissue. Spectroscopic analysis detected BCP crystals in 75% of cartilage and 43% of synovial samples. CPP deposition was only detected in 18% of cartilage and 15% of synovial samples, often coinciding with BCP deposits.

CONCLUSION

BCP is the predominant crystal type in calcified cartilage and synovium while CPP deposition is rare, often coinciding with BCP. Distinct and qualitative information on BCP and CPP deposits in joint tissues gives rise to the speculation that different disease entities are involved that might need different treatment strategies.

Bilateral rapidly destructive coxopathy in rheumatoid arthritis

Rapidly destructive coxopathy (RDC) is a rare type of coxarthritis marked by swift deterioration of the hip joint. Although its cause remains unclear, several pathophysiological mechanisms are proposed. To comprehensively analyze this poorly understood condition, a literature search was conducted focusing on associations of bilateral RDC and rheumatoid arthritis (RA). The problem of long-standing RA, bilateral RDC with a febrile episode that preceded a rapid decline in mobility and severe hip pain, with radiological assessment confirmed bilateral hip destruction, was presented. Rapidly destructive coxopathy, especially when linked to RA, poses diagnostic and therapeutic challenges. Our review confirmed by the clinical picture emphasizes the need for vigilance in RA patients with hip involvement and calls for further research to understand RDC's mechanisms and enhance clinical care.

Crystal induced arthropathies-a comparative study of 40 patients with apatite rheumatism, chondrocalcinosis and primary synovial chondromatosis

Introduction: Apatite rheumatism (AR), chondrocalcinosis (Ch-C), and primary synovial chondromatosis (prSynCh) are regarded as distinct clinical entities. The introduction of the non-staining technique by Bély and Apáthy (2013) opened a new era in the microscopic diagnosis of crystal induced diseases, allowing the analysis of MSU (monosodium urate monohydrate) HA (calcium hydroxyapatite), CPPD (calcium pyrophosphate dihydrate) crystals, cholesterol, crystalline liquid lipid droplets, and other crystals in unstained sections of conventionally proceeded (aqueous formaldehyde fixed, paraffin-embedded) tissue samples. The aim of this study was to describe the characteristic histology of crystal deposits in AR, Ch-C, and prSynCh with traditional stains and histochemical reactions comparing with unstained tissue sections according to Bély and Apáthy (2013). Patients and methods: Tissue samples of 4 with apatite rheumatism (Milwaukee syndrome), 16 with chondrocalcinosis, and 20 with clinically diagnosed primary synovial chondromatosis were analyzed. Results and conclusion: Apatite rheumatism, chondrocalcinosis, and primary synovial chondromatosis are related metabolic disorders with HA and CPPD depositions. The authors assume that AR and Ch-C are different stages of the same metabolic disorder, which differ from prSynCh in amorphous mineral production, furthermore in the production of chondroid, osteoid and/or bone. prSynCh is a defective variant of HA and CPPD induced metabolic disorders with reduced mineralization capabilities, where the deficient mineralization is replaced by chondroid and/or bone formation. The non-staining technique of Bély and Apáthy proved to be a much more effective method for the demonstration of crystals in metabolic diseases than conventional stains and histochemical reactions.

Synthesis and docking studies of N-(5-(alkylthio)-1,3,4-oxadiazol-2-yl)methyl)benzamide analogues as potential alkaline phosphatase inhibitors

A series of N-(5-(alkylthio)-1,3,4-oxadiazol-2-yl)methyl)benzamides 6a-i were synthesized as alkaline phosphatase inhibitors. The intermediate 5-substituted 1,3,4-oxadiazole-2-thione 4 was synthesized starting with hippuric acid. Hippuric acid in the first step was converted into corresponding methyl ester 2 which upon reaction with hydrazine hydrate furnished the formation of hydrazide 3. The hippuric acid hydrazide was then cyclized into 5-substituted 1,3,4-oxadiazole-2-thione 4. The intermediate 4 was then reacted with alkyl or aryl halides 5a-5i to afford the title compounds N-(5-(methylthio)-1,3,4-oxadiazol-2-yl)methyl)benzamides 6a-i. The bioassay results showed that compounds 6a-i exhibited good to excellent alkaline phosphatase inhibitory activity. The most potent activity was exhibited by the compound 6i having IC₅₀ value 0.420 μM, whereas IC₅₀ value of standard (KH₂ PO₄ ) was 2.80 μM. Molecular docking studies was performed against alkaline phosphatase enzyme (PDBID 1EW2) to check binding affinity of the synthesized compounds 6a-i against target protein. The docking results showed that three compounds 6c, 6e, and 6i have maximum binding interactions with binding energy values of -8 kcal/mol. The compound 6i displayed the interactions of oxadiazole ring nitrogen with amino acid His265 having a binding distance 2.13 Ǻ. It was concluded from our results that synthesized compounds, especially compound 6i may serve as lead structure to design more potent inhibitors of human alkaline phosphatase.

S3-Guideline non-traumatic adult femoral head necrosis

INTRODUCTION

The treatment of adult non-traumatic avascular necrosis of the femoral head (AVN; N-ANFH) within an estimated incidence of 5000-7000 cases per annum in Germany remains a challenge. Risk factors include steroids, alcohol abuse, chemotherapy and immunosuppressive medication, but a genetic predisposition has been suggested. Early diagnosis of this often bilateral disease process is essential for successful conservative or joint preserving surgical management. In this review, we present the update German consensus S3 guideline "diagnosis and management for N-ANFH" as a concise summary.

MATERIALS AND METHODS

This systematic review is based on the published literature from January 1, 1970 to April 31, 2013 (German and English language). Inclusion criteria were systematic reviews, meta-analyses and relevant peer review publications. We identified a total of 3715 related publications, of which 422 were suitable according to the SIGN criteria, but only 159 fulfilled our inclusion criteria.

RESULTS AND CONCLUSIONS

Clinical suspicion of N-ANFH mandates radiographic evaluation. If radiographs are normal MRI scans are recommended, which should be evaluated according to the ARCO-classification. Differential diagnoses include transient osteoporosis, bone bruise, insufficiency fracture and destructive arthropathy. Untreated, subchondral fractures commonly occur within 2 years, during which the risk for contralateral involvement is high-thereafter unlikely. Conservative management with Ilomedin and Alendronat can be tried, but other pharmacological or physical treatments are inappropriate. No specific joint preserving procedure can be recommended, but core decompression should be considered in early stages if necrosis is <30 %. In ARCO stages IIIc or IV total hip arthroplasty (THA) should be contemplated, which offers similar outcome compared to osteoarthritis. Young age is the main risk factor for higher revision rates after THA for N-ANFH.

Rapid hip osteoarthritis development in a patient with anterior acetabular cyst with sagittal alignment change

Rapidly destructive coxarthrosis (RDC) is rare and develops unusual clinical course. Recent studies suggest multiple possible mechanisms of the development of RDC. However the exact mechanism of RDC is still not clear. The difficulty of the study on RDC is attributed to its rareness and the fact that the data before the onset of RDC is normally unavailable. In this report, we presented the patient having the radiographic data before the onset who had rapid osteoarthritis (OA) development after contralateral THA, which meets the current criteria of RDC. We thought that the increased posterior tilt of the pelvis after THA reinforced the stress concentration at pre-existed anterior acetabular cyst, thereby the destruction of the cyst was occurred. As a result the rapid OA was developed. We think that there is the case of rapid osteoarthritis developing due to alternating load concentration by posterior pelvic tilt on preexisting anterior acetabular cyst such as our patient among the cases diagnosed as RDC without any identifiable etiology. The recognition of sagittal alignment changes and anterior acetabular cyst may play important role in prediction and prevention of the rapid hip osteoarthritis development similar to RDC.

Massive accumulation of osteoclastic giant cells in rapid destructive hip disease

The term rapid destructive hip disease (RDHD) designates a rare coxarthropathy characterized by a rapid destruction of the femoral head within a few weeks to several months. The etiology and pathogenesis of RDHD are not understood. The goal of this study was to define the histological and histomorphometric hallmarks of RDHD to provide a basis for a deeper understanding of the underlying mechanisms. Fifteen consecutive RDHD patients (mean age 78.9 ± 6.4 years, 14 females) demonstrated the characteristic radiographic appearance of vanishing femoral head bone stock without signs of reactive anabolic changes. Histologic and histomorphometric analyses revealed severe bone resorption with significantly increased numbers of morphologically altered giant osteoclasts, the formation of giant cell granulomas both in bone marrow and the synovium and significantly increased osteoblast numbers and osteoid as compared to controls with primary osteoarthritis (OA). These results suggest that in RDHD, an unknown stimulus leads to a massive activation of osteoclasts and this in turn provokes a reactive increase in osteoblast activity that is too weak to counteract the rapid destruction of the hip, thus providing a rationale for a prospective systematic search for the stimuli upstream of the massively increased osteoclast activation in RDHD.

Hydroxyapatite crystal deposition forming para-articular multiple large masses: a case report and literature review

Multiple para-articular large masses are a rare form of hydroxyapatite (HA) crystal deposition, thereby limiting the clinical and imaging recognition and the ability to optimize diagnostic tools. The imaging features of para-articular large mass caused by HA crystal deposition are not well described in the sonographic literature. In this report, we present the case of a uremia patient with long period of maintenance hemodialysis, who was complicated with HA crystals depositing on the para-articular of elbow, knee, and shoulder and forming multiple large masses. We reviewed the literature to explore the ideal methods to establish a diagnosis. In addition, we performed a characterization of the sonographic features of HA crystals. We have established methods which serve to distinguish HA crystal deposition from other crystal deposit conditions.