C-reactive protein of ≥ 20 mg/L and ultrasound finding of an effusion ≥ 7 mm has a high specificity and sensitivity in diagnosing paediatric hip septic arthritis.

PURPOSE: Differentiating septic arthritis (SA) from transient synovitis (TS) in children remains a diagnostic challenge. Several algorithms have been developed to diagnose SA including Kocher's criteria and its subsequent modifications, but reports show variable efficacy. This study aims to examine the diagnostic utility of a novel method only using C-reactive protein (CRP) and ultrasound (US) findings of effusion in differentiating SA from TS, determine the optimal values for these predictors and validate this method against existing clinical predictors. METHODS: A 5-year retrospective study was performed including all paediatric patients with acute, non-traumatic hip pain with a suspicion of SA. All patients were evaluated using Kocher's criteria, Caird's criteria, and the novel method. Multivariate logistic regression was performed to identify independent clinical predictors of SA. The degree of agreement between the various methods were assessed using Cohen's kappa (k). Receiver operating characteristics (ROC) curves were used to examine the diagnostic accuracy of this novel method as well as to determine optimal cut-offs for US effusion and CRP in diagnosing SA. RESULTS: Hundred and one patients were recruited. CRP and effusion on US were found to be independent predictors of SA. Both Kocher's and Caird's method showed good specificity (98.9%) but extremely poor sensitivity for SA (0%). When Kocher's four clinical predictors were present, probability of SA was only 59.16%. The k for both Kocher's and Caird's methods, was -0.017 indicating poor agreement. However the k in the novel method was 0.641, indicating good agreement. CONCLUSION: Our study showed that the novel method using CRP (≥ 20 mg/L) and US finding of effusion (≥ 7 mm) has a high specificity (97%) and sensitivity (71%) in diagnosing SA.

Identification of N-glycoproteins of hip cartilage in patients with osteonecrosis of femoral head using quantitative glycoproteomics.

N-glycosylation is a major post-translational modification of proteins and involved in many diseases, however, the state and role of N-glycosylation in cartilage degeneration of osteonecrosis of femoral head (ONFH) remain unclear. The aim of this study is to identify the glycoproteins of ONFH hip cartilage. Cartilage tissues were collected from nine patients with ONFH and nine individuals with traumatic femoral neck fracture. Cartilage glycoproteins were identified by glycoproteomics based on LC-MS/MS. The differentially N-glycoproteins including glycosites were identified in ONFH and controls. A total of 408 N-glycoproteins with 444 N-glycosites were identified in ONFH and control cartilage. Among them, 104 N-glycoproteins with 130 N-glycosites were significantly differential in ONFH and control cartilage, which including matrix-remodeling-associated protein 5, prolow-density lipoprotein receptor-related protein 1, clusterin and lysosome-associated membrane glycoprotein 2. Gene Ontology analysis revealed the significantly differential glycoproteins mainly belonged to protein metabolic process, single-multicellular organism process, proteolysis, biological adhesion and cell adhesion. KEGG pathway and protein-protein interaction analysis suggested that the significantly differential glycoproteins were associated with PI3K-Akt signalling pathway, ECM-receptor interaction, protein processing in the endoplasmic reticulum and N-glycan biosynthesis. This information provides substantial insight into the role of protein glycosylation in the development of cartilage degeneration of ONFH patients.

Determining Trendelenburg test validity and reliability using 3-dimensional motion analysis and muscle dynamometry.

BACKGROUND: The hip abductor muscle group stabilises the pelvis during gait to prevent excessive pelvic drop. Hip abductor weakness has been linked to musculoskeletal conditions such as chronic low-back pain. As such, it is important that practitioners can correctly diagnose hip abductor weakness in a clinical setting. Although the Trendelenburg test is commonly used by practitioners, the validity of this test to assess hip abductor weakness in the absence of musculoskeletal injury remains questionable. The aim of this study was to determine the validity of the Trendelenburg test, as observed by a practitioner, to assess frontal plane pelvic motion and hip abductor strength in a population without intra-articular hip disorders. METHODS: This study was performed between June 14th and October 16th 2019. Eighteen participants were recruited for this study. Peak normalised isometric and isokinetic hip abductor torque were measured bilaterally (n = 36) using the Biodex System 4 isokinetic dynamometer. Each participant performed the Trendelenburg test bilaterally (n = 36) while a graduate year chiropractic practitioner assessed for a "positive" or "negative" sign. The test was simultaneously recorded using Vicon 3-Dimensional motion capture to measure frontal plane pelvic motion and elevation. Correlation analyses were performed between the measures of peak hip abductor torque and pelvic motion to determine if any relationship existed. Agreement between the practitioner and 3-Dimensional analysis was calculated using the kappa (κ) statistic. RESULTS: Weak, non-significant correlations were found between hip abductor strength and pelvic motion before outlier removal. Significant (p < 0.05) yet weak correlations were found after outlier removal, except for isometric hip abductor strength. Weak agreement was found between the chiropractic practitioner and 3-Dimesnional analysis for the Trendelenburg test assessment (κ = 0.22-0.25). CONCLUSIONS: This study found no significant relationship between normalised peak isometric and isokinetic hip abductor torque and frontal plane pelvic motion during the Trendelenburg test in a healthy young adult population. There was also poor agreement between the practitioner and pelvic motion assessments. Caution should be used when using this test, in the absence of intra-articular hip pathology, to assesses hip abductor weakness. Before any definitive conclusion can be made, studies with a larger sample size should be performed.

Laboratory-based versus qualitative assessment of α-defensin in periprosthetic hip and knee infections: a systematic review and meta-analysis.

INTRODUCTION: Two methods are currently available for the assay of α-defensin: the enzyme-linked immunosorbent assay (ELISA) and the lateral flow test. We aimed to assess the diagnostic accuracy of synovial fluid α-defensin and to compare the accuracy of the laboratory-based test and the qualitative assessment for the diagnosis of hip and knee prosthetic infection. MATERIALS AND METHODS: We searched (from inception to May 2018) MEDLINE, Scopus, EMBASE, Web of Science, and Cochrane for studies on α-defensin in the diagnosis of periprosthetic joint infection (PJI). Sensitivity, specificity, positive and negative likelihood ratio (LR), and diagnostic odds ratio were analyzed using the bivariate diagnostic random-effects model. The receiver-operating curve for each method was calculated. RESULTS: We included 13 articles in our meta-analysis, including 1170 patients who underwent total hip and knee arthroplasties revision; 368 (31%) had a joint infection according to MSIS and MSIS-modified criteria. Considering the false-positive result rate of 8% and false-negative result rate of 3%, pooled sensitivity and specificity were 0.90 (95% CI 0.83-0.94) and 0.95 (0.92-0.96), respectively. The area under the curve (AUC) was 0.94 (0.92-0.94). No statistical differences in terms of sensitivity and specificity were found between the laboratory-based and qualitative test. The pooled sensitivity and specificity of the two alpha-defensin assessment methods were: laboratory-based test 0.97 (95% CI 0.93-0.99) and 0.96 (95% CI 0.94-0.98), respectively; qualitative test 0.83 (95% CI 0.73-0.91) and 0.94 (95% CI 0.89-0.97), respectively. The diagnostic odds ratio of the α-defensin laboratory based was superior to that of the qualitative test (1126.085, 95% CI 352.172-3600.702 versus 100.9, 95% CI 30.1-338.41; p < 0.001). The AUC for immunoassay and qualitative tests was 0.97 (0.95-0.99) and 0.91 (0.88-0.99), respectively. CONCLUSION: Detection of α-defensin is an accurate test for diagnosis of hip and knee prosthetic infections. The diagnostic accuracy of the two alpha-defensin assessment methods is comparable. The lateral flow assay is a valid, rapid, and more available diagnostic tool, particularly to rule out PJI.

Solochrome cyanine: A histological stain for cobalt-chromium wear particles in metal-on-metal periprosthetic tissues.

Metal-on-metal (MoM) hip arthroplasties produce abundant implant-derived wear debris composed mainly of cobalt (Co) and chromium (Cr). Cobalt-chromium (Co-Cr) wear particles are difficult to identify histologically and need to be distinguished from other wear particle types and endogenous components (e.g., haemosiderin, fibrin) which may be present in MoM periprosthetic tissues. In this study we sought to determine whether histological stains that have an affinity for metals are useful in identifying Co-Cr wear debris in MoM periprosthetic tissues. Histological sections of periprosthetic tissue from 30 failed MoM hip arthroplasties were stained with haematoxylin-eosin (HE), Solochrome Cyanine (SC), Solochrome Azurine (SA) and Perls' Prussian Blue (PB). Sections of periprosthetic tissue from 10 cases of non-MoM arthroplasties using other implant biomaterials, including titanium, ceramic, polymethylmethacrylate (PMMA) and ultra-high molecular weight polyethylene (UHMWP) were similarly analysed. Sections of 10 cases of haemosiderin-containing knee tenosynovial giant cell tumour (TSGCT) were also stained with HE, SC, SA and PB. In MoM periprosthetic tissues, SC stained metal debris in phagocytic macrophages and in the superficial necrotic zone which exhibited little or no trichrome staining for fibrin. In non-MoM periprosthetic tissues, UHMWP, PMMA, ceramic and titanium particles were not stained by SC. Prussian Blue, but not SC or SA, stained haemosiderin deposits in MoM periprosthetic tissues and TSGT. Our findings show that SC staining (most likely Cr-associated) is useful in distinguishing Co-Cr wear particles from other metal/non-metal wear particles types in histological preparations of periprosthetic tissue and that SC reliably distinguishes haemosiderin from Co-Cr wear debris.

Gout Presenting as Acute Hip Pain in a Young Woman: A Case Report.

CASE: A 28-year-old previously healthy woman developed worsening right hip pain without any preceding trauma or injury. Because of concern for septic arthritis, she underwent arthroscopic irrigation and debridement. The culture specimens were negative; crystal analysis showed monosodium urate crystals, which are consistent with an acute gout flare. The patient was started on naproxen and prednisone therapy and had substantial improvement in hip pain. CONCLUSION: Gout is a common cause of joint pain in older individuals. While rare in younger patients, our case report shows that gout should be included in the differential diagnosis when a patient presents with acute monoarthritis, regardless of age.

An analysis of factors affecting the mercury content in the human femoral bone.

The study was carried out to determine the content of mercury in bone tissue of the proximal femur (head and neck bone) of 95 patients undergoing total hip replacement due to osteoarthritis, using CF-AFS analytical technique. Furthermore, the investigations were aimed at assessing the impact of selected factors, such as age, gender, tobacco smoking, alcohol consumption, exposure to chemical substance at work, type of degenerative changes, clinical evaluation and radiological parameters, type of medications, on the concentration of mercury in the head and neck of the femur, resected in situ. Mercury was obtained in all samples of the head and neck of the femur (n = 190) in patients aged 25-91 years. The mean content of mercury for the whole group of patients was as follows: 37.1 ± 35.0 ng/g for the femoral neck and 24.2 ± 19.5 ng/g for the femoral head. The highest Hg contents were found in femoral neck samples, both in women and men, and they amounted to 169.6 and 176.5 ng/g, respectively. The research showed that the mercury content of bones can be associated with body mass index, differences in body anatomy, and gender. The uses of statistical analysis gave the possibility to define the influence of factors on mercury content in human femoral bones.

[Supramacroparticulate polyethylene in inflammation of synovial-like interface membranes: Characterization and suggested nomenclature]. / Supramakropartikuläres Polyethylen bei Entzündungen periprothetischer Membranen: Charakterisierung und Nomenklaturvorschlag.

BACKGROUND: The identification of particles of prosthesis material components in the histopathological diagnosis of synovialitis is of great importance in the evaluation of implant failure. MATERIALS AND METHODS: In histopathological particle algorithms, polyethylene (PE) particles with a maximum length of less than 100 µm are designated with the term macroparticles; however, a systematic investigation and characterization are lacking. RESULTS: In SLIM knee specimens (n = 24) a minimum value of 210 µm and a maximum value of 2100 µm were measured; the mathematical mean length varied between 235 µm and 1416 µm. In SLIM hip specimens (n = 11) the minimum value was 290 µm and the maximum value was 1806 µm; the mean length varied between 353 and 1726 µm. Because of this conspicuous size, and to distinguish from PE macroparticles, the designation PE supra-macroparticulate is suggested. This new terminology acknowledges the fact that these PE particles are visible under magnification (e.g., × 12.5) and also macroscopically. The particles were also indirectly proven as there were completely separate and optically clear, column-shaped cavities corresponding to the shape of the PE particles (PE vacuoles). The life of the prosthesis is highly variable at between 12 and 300 months. In all cases loosening of the prosthesis, misalignment of the PE components, and/or damage to the PE inlay occurred. CONCLUSION: The cause and existence of these supra-macroparticulate PE particles (more than 100 µm) is still unclear. A mechanical malfunction seems probable and should be discussed. In prostheses with short lives the proof of supra-macroparticulate PE in SLIM could be a sign of an early mechanical problem. In the wider histopathological particle algorithm supra-macroparticulate PE was considered to fall in the category of macroparticles and should be considered in the histopathological diagnosis of implant failure.

Diagnostic utility of joint fluid metal ion measurement for histopathological findings in metal-on-metal hip replacements.

BACKGROUND: In vivo assessment of inflammatory responses in the synovia of patients with MoM hip replacements would be useful in the determination of the prognosis of the hip replacement. Aims of the study was to investigate the correlation between cobalt and chrome levels in joint fluid with histopathological findings and the predictive ability of metal ion levels for these findings. METHODS: In 163 revision surgeries (141 ASR THAs and 22 ASR hip resurfacings) joint fluid chrome and cobalt levels were assessed and histological analysis of synovial tissues was performed. Histological analysis included assessment of histiocytes, particle load, surface necrosis, lymphocyte cuffs and ALVAL-score. RESULTS: Surface necrosis correlated positively with cobalt levels both in both groups. Neither chrome nor cobalt level had even fair discriminative ability to predict the presence or severity of any histological finding in the THA group. In the hip resurfacing group, cobalt level had good discriminative ability to predict the presence of perivascular lymphocytes and ALVAL-score of ≥ 7 whereas chrome had good discriminative ability to predict surface necrosis, metal particle load and ALVAL-score of ≥ 7. CONCLUSIONS: Measurement of metal ion levels following joint fluid aspirate offers no relevant information with regard to histopathological findings in patients with large-diameter MoM THAs. Limited information may be gained from assessment of joint fluid metal ion levels in patients with hip resurfacings, but disadvantages of an aspirate must be carefully reviewed.

Involvement of Notch1/Hes signaling pathway in ankylosing spondylitis.

We aimed to investigate the role of Notch1/Hes signaling pathway in the pathogenesis of abnormal ossification of hip ligament in patients with ankylosing spondylitis (AS). 22 AS patients scheduled for artificial hip arthroplasty were randomly chosen as AS group. As controls, we used 4 patients diagnosed with transcervical fracture who underwent hip replacement surgery. Notch1 and Hes mRNA expressions were detected by real-time fluorescent quantitative polymerase chain reaction (RFQ-PCR). Immunohistochemistry (IHC) was used to detect Notch1 and Hes protein expression. Correlation analyses of Notch-l and Hes with AS-related clinical factors were conducted with spearman's correlation analysis and partial correlation analysis. RFQ-PCR results showed significant differences in Notch1 and Hes mRNA expressions between AS group and the control group (all P<0.05). IHC analysis further indicated positive nuclear signals of Notch1 and Hes protein, indicating functional activation of the Notch1 and Hes pathways. Semi-quantitative IHC showed a higher Notch1 and Hes expression levels in AS group compared to the control group (all P<0.05). Correlation analysis suggested that Hes protein expression was positively associated with the clinical course of the disease in AS patients. In conclusion, Notch1 and Hes overexpression was clearly detected in hip joint ligaments of AS patients, Hes protein expression was associated with the clinical course of AS. Taken together, we suggest that signaling pathways mediated by Notch1-Hes may contribute to ligament ossification of hip joints in AS patients.

[Low-Carbon Metal-on-Metal Articulations for Hip Arthroplasties--Evaluation of Wear and Histology after 11 to 17 Years]. / Verschleißtechnische Analysen und histologische Befunde bei Low-Carbon-Metall-Metall-Artikulationen des Hüftgelenks nach 11 bis 17 Jahren.

BACKGROUND: High-carbon (HC) alloys for hip arthroplasties were preferred to low-carbon (LC) alloys for a long time because of their structurally hard carbide content. We opted for an LC alloy in 1994, because we expected it to be subject to less wear on account of its more homogeneous structure. Prompted by early complications not seen with ceramic-on-polyethylene mating surfaces, LC metal-on-metal articulations were, however, given up by us in early 1999. A series of implants retrieved after 11 to 17 years was now studied to establish the actual amount of wear. Potential tissue reactions associated with hypersensitivity were also evaluated histologically and correlated with the measured wear and the amount of metal particles in capsular tissue. PATIENTS AND METHODS: Ten patients with LC metal-on-metal hip implants were the subjects of analyses after a mean follow-up time of 13.9 years. They underwent revision surgery because of osteolysis, cup loosening without dislocation, late infection in 1 patient and pain. The implant positions at the time of retrieval were the same as on the postoperative radiographs. Wear was determined in keeping with ISO 14242-2 and by SEM. In addition, periprosthetic tissue including the joint capsule and interface membranes were obtained for histological analysis. The amount of metal particles and the extent of lymphocyte infiltration were determined with the method described by Willert et al. Tissue alterations were evaluated histologically for signs of ALVAL using the method of Campbell et al. and correlated with the amount of wear and metal particles. RESULTS: The mean maximum linear wear rate was found to be 1.6 (1.0-2.1) µm/year. Our data also showed a mean rate of 0.32 mm³/year (range, 0.22-0.47 mm³/year). This is equivalent to an annual metal release of 2.7 (1.9-3.9) mg/year. No corrosion or corrosion products were present on the ball heads and their taper. All mating surfaces studied by SEM showed signs of abrasion. Sporadically, additional abrasions in the submicrometer range were detected on the ball head surfaces. These were caused by corundum particles detached from the blasted implant surfaces and interpreted as third-body wear below the level of quantification. Signs of impingement were absent. Histologically, metal wear particles of variable amount were detected in all cases. In 4 of them solid corrosion products were present in the tissue. The ALVAL scores were 5 to 10 (moderate to high), but did not correlate with the measured wear and the amount of metal particles. CONCLUSION: The wear of LC articulations found after years of implant survival was very low. In fact, it was lower than the data reported for HC articulations and would permit implants to function for decades in engineering terms. However, their survival is limited by tissue alterations associated with hypersensitivity. These tissue alterations may contribute to implant loosening as also reported for HC articulations. They are apparently not related to the actual amount of wear and may reflect adaptive immunological processes.

Chromium content in the human hip joint tissues.

OBJECTIVE: Chromium has many important functions in the human body. For the osseous tissue, its role has not been clearly defined. This study was aimed at determining chromium content in hip joint tissues. METHODS: A total of 91 hip joint samples were taken in this study, including 66 from females and 25 from males. The sample tissues were separated according to their anatomical parts. The chromium content was determined by the AAS method. The statistical analysis was performed with U Mann-Whitney's non-parametric test, P≤0.05. RESULTS: The overall chromium content in tissues of the hip joint in the study subjects was as follows: 5.73 µg/g in the articular cartilage, 5.33 µg/g in the cortical bone, 17.86 µg/g in the cancellous bone, 5.95 µg/g in the fragment of the cancellous bone from the intertrochanteric region, and 1.28 µg/g in the joint capsule. The chromium contents were observed in 2 group patients, it was 7.04 µg/g in people with osteoarthritis and 12.59 µg/g in people with fractures. CONCLUSION: The observed chromium content was highest in the cancellous bone and the lowest in the joint capsule. Chromium content was significantly different between the people with hip joint osteoarthritis and the people with femoral neck fractures.

Mild degenerative changes of hip cartilage in elderly patients: an available sample representative of early osteoarthritis.

This study investigated the cellular and molecular changes which occur in cartilage from adults with femoral neck fracture (FNF) and osteoarthritis (OA), and explored the similarities in hip cartilage obtained from elderly patients and patients with early OA. Femoral heads were retrieved from 23 female patients undergoing total hip arthroplasty (THA). This group included 7 healthy patients with FNF (hFNF), 8 elderly adults with FNF (eFNF), and 8 elderly patients with hip OA (OA). After high-field MRI T2 mapping, osteochondral plugs were harvested from the weight-bearing area of femoral heads for subsequent macroscopic, histologic, and immunochemical evaluation. Additionally, the contents of cartilage matrix were analyzed, and gene expression was detected. The surface of cartilage from hFNF and eFNF patients appeared smooth, regular, and elastic, whereas it showed irregularities, thinning, and defects in OA patients. Elevated T2 values and decreased accumulation of glycosaminoglycans (GAGs) were detected in cartilage from eFNF patients. Furthermore, type I collagen accumulation was slightly increased and type X collagen concentration was obviously elevated in eFNF patients; however, type II collagen distribution and the contents and anisotropy of collagen fibrils in eFNF patients showed no significant changes. Consistent with histology and immunohistochemical results, aggrecan was downregulated and type X collagen was upregulated, while collagens types I and II showed no significant changes in eFNF patients. The cellular and molecular characteristics of hip cartilage in eFNF patients who showed no symptoms of OA were similar to those in patients with mild OA. Thus, eFNF cartilage can serve as a comparative specimen for use in studies investigating early OA.

Biochemical analyses of human osteoarthritic and periprosthetic synovial fluid.

Biochemical analyses were performed on osteoarthritic and periprosthetic synovial fluid in order to propose changes to lubricant specifications currently outlined in orthopaedic wear testing standards. Osteoarthritic and periprosthetic synovial fluid samples were obtained from the hip and knee joints of 40 patients. The samples in each group were analysed and compared in order to identify differences between the protein concentration, constituent fractions, osmolality, thermal stability and the hyaluronic acid concentration and molecular weight distribution of osteoarthritic and periprosthetic synovial fluid. The average total protein concentration was approximately 30 g/L, which was much higher than the 20 g/L currently specified in the knee wear testing standard; however, the 30 g/L protein concentration matched the recently revised standard for hip simulator wear testing. No significant difference was found between the protein concentration, osmolality, thermal stability, and hyaluronic acid concentration of osteoarthritic and periprosthetic synovial fluid. The clinical data provided should be used to better define the composition of a more clinically relevant lubricant for orthopaedic wear testing.

Distribution of magnesium, calcium, sodium and potassium in tissues of the hip joint.

The aim of this study was to determine the distribution of magnesium, calcium, sodium and potassium in tissues of the hip joint and to look for any correlations between these minerals. The study was performed using hip joint samples taken from people living in the Upper Silesian Industrial Region in Poland. Ninety one subjects, 66 women and 25 men, were included in this study. The samples were obtained intra-operatively during hip joint replacement procedures. The concentrations of magnesium, calcium, sodium and potassium were measured by atomic absorption spectrophotometry (AAS). Our results showed that these minerals are most abundant in the cancellous bone of the hip joint. They were found next more abundantly in the cortical bone and the cancellous bone from the intertrochanteric area. Levels of magnesium, potassium and calcium were lower in articular cartilage compared with other parts of the hip joint; however, sodium levels were at their highest in this tissue. The lowest levels of these minerals were found in the articular capsule. Those patients with fractures of the femoral neck had lower levels of magnesium, potassium, and calcium, but higher levels of sodium compared with the group with degenerative changes. We can also confirm that in the population studied, calcium levels in cancellous bone of the head of the femur decreased with age.

Periprosthetic tissue metal content but not serum metal content predicts the type of tissue response in failed small-diameter metal-on-metal total hip arthroplasties.

BACKGROUND: Tissue responses to periprosthetic metal wear debris are complex and poorly understood. There are two predominant tissue responses: a nonspecific macrophage-mediated granulomatous response and lymphocyte-dominated response, which has immunological memory and is mediated by T cells. Delayed hypersensitivity-type responses may accelerate aseptic loosening of arthroplasty implants. We hypothesized that the metal content of periprosthetic tissue but not of serum would be predictive of the type of tissue response to metal wear debris. METHODS: We examined twenty-eight total hip arthroplasty implant retrievals from twenty-seven patients who had undergone revision arthroplasty at one institution. Indications for revision were pain and/or osteolysis; one patient had recurrent dislocations. Tissue samples were analyzed microscopically and the metal (Co, Cr, and Ni) content was determined. Explanted prosthetic components were examined for linear wear. Intraoperatively, periprosthetic metallosis was observed in twelve cases and formation of a bursa (pseudotumor) was observed in thirteen. The acetabular cup was loose in eleven cases, the femoral stem was loose in five, and both components were loose in five. RESULTS: The metal (Co, Cr, and Ni) content of the periprosthetic tissue ranged from 1.4 to 4604.0 µg/g. Histologically, macrophages containing metal particles as well as diffuse and perivascular lymphocytic infiltration were observed. Fibrin exudation was also visible. Tissues that displayed a predominantly lymphocytic response had a mean metal content of 222.2 ± 52.9 µg/g, whereas those that displayed a macrophage-dominated response had a metal content of 3.0 ± 0.9 µg/g; this difference was significant (p = 0.001). The mean serum metal content did not differ significantly between the two subgroups (60.7 ± 13.4 compared with 43.7 ± 3.8 µg/L, p = 0.105). CONCLUSIONS: An association between periprosthetic tissue metal content and hypersensitivity appears likely but needs to be validated with larger-scale retrieval studies. CLINICAL RELEVANCE: This study contributes to the understanding of tissue responses to metal wear debris after joint replacement and the factors that are predictive of a type-IV lymphocyte-dominated hypersensitivity reaction.

The effect of environmental factors on concentration of trace elements in hip joint bones of patients after hip replacement surgery.

The aim of this study was to assess the impact of environmental factors: cigarette smoking, dental amalgam fillings, eating habits and osteoporosis, on the concentrations of copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd) and mercury (Hg) in the bone of hip joint in patients in the Orthopedics Clinic in Szczecin, Poland. Amalgam dental fillings had an effect on the Cu concentration in the cartilage with the adjacent compact bone, and on Hg concentration in the spongy bone. The highest concentrations of Cu and Hg were found in people with multiple amalgam fillings. Smoking appeared to influence Pb concentration in the cartilage with the adjacent compact bone, and Cd concentration in the spongy bone. Increased Pb was detected in smokers, and increased Cd in non-smokers. Diets rich in fish and seafood correlated with Cd concentration in the cartilage with adjacent compact bone. The greatest concentration was in people who ate fish or seafood at least once a month.

Thyroid dysfunction in an adult female population: A population-based study of Latin American Vertebral Osteoporosis Study (LAVOS) - Puerto Rico site.

OBJECTIVE: To determine the prevalence of hypothyroidism in an adult female population in Puerto Rico and to determine the relationship between hypothyroidism, bone mineral density and vertebral and non-vertebral fractures in this population. METHODS: Data from the 400 subjects' database of the Latin American Vertebral Osteoporosis Study (LAVOS), Puerto Rico site was reviewed. Patient's medical history, anthropometric data, current medications, laboratories, and DXA results was extracted. Subjects with thyroid dysfunction were identified based on their previous medical history and levels of TSH. Bone Mineral Density was classified using the World Health Organization criteria. Crude prevalence of thyroid dysfunction were estimated with a confidence of 95% and weighted by the population distribution by age, according to the distribution by age group in the 2000 census. Bone mineral densities and prevalence of vertebral and non-vertebral fractures were compared among the groups. RESULTS: The weighted prevalence of hyperthyroidism in this population was 0.0043% (95% CI: -0.0021%, 0.0107%). The weighted prevalence of hypothyroidism was 24.2% (95% CI: 19.9%, 28.4%). Increased prevalence of hypothyroidism was found in participants 70 years or older. The mean BMD at spine, hip and femoral neck was similar among the groups. No difference in the proportion of participants with vertebral and non-vertebral fractures was found among the groups. CONCLUSION: Our study found a high prevalence of hypothyroidism among adult postmenopausal females in Puerto Rico. No association between hypothyroidism and decreased bone mineral densities, vertebral or non-vertebral fractures was found in this population.

Allelic expression analysis of the osteoarthritis susceptibility gene COL11A1 in human joint tissues.

BACKGROUND: The single nucleotide polymorphism (SNP) rs2615977 is associated with osteoarthritis (OA) and is located in intron 31 of COL11A1, a strong candidate gene for this degenerative musculoskeletal disease. Furthermore, the common non-synonymous COL11A1 SNP rs1676486 is associated with another degenerative musculoskeletal disease, lumbar disc herniation (LDH). rs1676486 is a C-T transition mediating its affect on LDH susceptibility by modulating COL11A1 expression. The risk T-allele of rs1676486 leads to reduced expression of the COL11A1 transcript, a phenomenon known as allelic expression imbalance (AEI). We were keen therefore to assess whether the effect that rs1676486 has on COL11A1 expression in LDH is also observed in OA and whether the rs2615977 association to OA also marked AEI. METHODS: Using RNA from OA cartilage, we assessed whether either SNP correlated with COL11A1 AEI by 1) measuring COL11A1 expression and stratifying the data by genotype at each SNP; and 2) quantifying the mRNA transcribed from each allele of the two SNPs. We also assessed whether rs1676486 was associated with OA susceptibility using a case-control cohort of over 18,000 individuals. RESULTS: We observed significant AEI at rs1676486 (p < 0.0001) with the T-allele correlating with reduced COL11A1 expression. This corresponded with observations in LDH but the SNP was not associated with OA. We did not observe AEI at rs2615977. CONCLUSIONS: COL11A1 is subject to AEI in OA cartilage. AEI at rs1676486 is a risk factor for LDH, but not for OA. These two diseases therefore share a common functional phenotype, namely AEI of COL11A1, but this appears to be a disease risk only in LDH. Other functional effects on COL11A1 presumably account for the OA susceptibility that maps to this gene.

The content of manganese and iron in hip joint tissue.

Manganese and iron are elements that constitute components of bone tissue. The aim of this study was to determine presence of manganese and iron in hip joint tissue and interdependencies between these elements. The objects of the research were hip joint elements from people residing in cities on the territory of the Upper Silesian Industrial District. The number of people in the study group was 91 samples, including 66 samples from women and 25 from a man. The examined tissues were obtained intraoperatively during hip replacement procedures. The content of manganese and iron was determined using the atomic absorption spectrophotometry (AAS) method. The lowest content of manganese and iron was found in the cortical bone, and the largest, in the case of manganese, in the articular cartilage, whereas in the case of iron in a fragment of the cancellous bone from the intertrochanteric area. The content of iron in selected elements of the hip joint decreased with age. Higher content of manganese in hip joint tissue of women compared to men was confirmed. What is more, higher content of iron in hip joint tissue of men was confirmed as well.