The Relationship Between Related Factors And The Contents Of Trace Elements In The Structure Of Knee Osteoarthritis And The Correlations Between Trace Elements

Objective:Osteoarthritis(OA)is a common chronic degenerative joint disease,which is characterized by articular cartilage degeneration and hyperosteogeny.Osteoarthritis may begin in certain parts of the joint,but eventually affecting the whole joint.The pathogenesis of osteoarthritis is complex,and its slow evolution involves mechanical,genetic,metabolic and inflammatory pathways.The risk factors of osteoarthritis include heredity,age,gender,metabolic disease,obesity,occupation,injury,diet,minerals and so on.In the process of long-term remodeling,the joints adapt to specific trace element levels.Any changes in trace element content,manifested as lack or excess in the human body,may affect the joint homeostasis,ultimately resulting in osteoarthritis.The impacts of trace elements on osteoarthritis are mainly determined by their types and concentrations.Some trace elements like boron can reduce the incidence rate of osteoarthritis and relieve its symptoms.However,exposure to toxic elements such as cadmium can lead to the occurrence and development of osteoarthritis.The positive and negative impacts of some trace elements depend on their concentrations.For example,copper is beneficial to joints at certain concentration.However,the beneficial window of copper concentration is very narrow,and too low or too high concentration may bring about osteoarthritis.The effects of trace elements on osteoarthritis are related to biological factors,environmental factors and health status.Researchers have paid more and more attention to the relationships between trace elements(boron,chromium,iron,zinc,copper,magnesium,manganese,strontium,aluminum,arsenic,cadmium and lead)and osteoarthritis.However,there are few population-based studies in China.Secondly,there are few studies on the effects of biological factors,environmental factors and health status on the contents of trace elements in the structure of knee osteoarthritis.Thirdly,most of the relevant studies are limited to single trace element and lack of the correlations between multiple trace elements.Therefore,this study determines the contents of trace elements(boron,chromium,iron,zinc,copper,magnesium,manganese,strontium,aluminum,arsenic,cadmium and lead)in the structure of knee osteoarthritis in China.We explore the relationships between age,gender,the place of residence,hypertension and diabetes and trace elements,and examine the correlations between trace elements,so as to provide theoretical basis for preventing and treating osteoarthritis.Methods:In this study,the demographic and health status of the subjects were collected through questionnaire survey,with special emphasis on the factors that may affect the concentrations of trace elements in the structure of knee osteoarthritis.Participants were grouped according to age,gender,residence,hypertension and diabetes.The samples of 51 patients with knee osteoarthritis undergoing total knee arthroplasty were collected.The femoral cancellous bone,femoral cartilage,anterior cruciate ligament,meniscus,tibial cartilage,tibial cancellous bone and subpatellar fat pad were separated.After the sample was marked with code,it was placed in a polyethylene container and stored in a refrigerator with the temperature of-22 ℃until determination.The samples were immersed in acetone to degrease,dried and crushed.Then,0.2 g of sample,5 ml of 65% concentrated nitric acid and 1 ml of30% hydrogen peroxide mixture were put into the digestion tank and dissolved in the microwave digestion system.The determination of 12 trace elements(boron,chromium,iron,zinc,copper,magnesium,manganese,strontium,aluminum,arsenic,cadmium and lead)in the samples were performed via inductively coupled plasma optic emission spectrometry.The calibration curve method was adopted.The statistical analysis was made using IBM SPSS Statistics,version 26.0.P < 0.05 was considered to be statistically significant.Results:1.There were statistically significant differences in the concentrations of boron,chromium,iron,zinc,copper,magnesium,manganese,strontium,aluminum,arsenic,cadmium and lead among the structures of knee osteoarthritis.The concentrations of boron,chromium,zinc,magnesium,strontium,aluminum,arsenic and lead in femoral cancellous bone were higher than in anterior cruciate ligament,while the concentrations of iron,copper,manganese and cadmium were higher in anterior cruciate ligament.2.There was statistically significant difference in the concentration of cadmium in tibial cancellous bone between men and women.The concentration of cadmium in tibial cancellous bone in women was about 60% higher than in men(0.077 and 0.048 mg / kg dw,U = 377,p = 0.049,respectively).The concentration of chromium in the anterior cruciate ligament in men was statistically significantly higher than in women(1.64 and 1.30 mg / kg dw,U = 381,p = 0.040,respectively).In the structure of knee osteoarthritis in women,the concentrations of boron,copper,iron and lead were higher than in men,while the concentration of arsenic was the opposite.Although the noticeable differences in the concentrations of arsenic,boron,copper,iron and lead in the studied samples,they were not statistically significant.Zinc concentration was almost the same in the structure of knee osteoarthritis between men and women.Between the age ≤ 65 years old group and the age > 65 years old group,the concentrations of boron and manganese in the structure of knee osteoarthritis in the age > 65 years old group were higher than in the age ≤ 65 years old group,while the concentration of cadmium had the opposite trend,but there were no statistically significant differences between the two age groups in the concentrations of trace elements in the structure of knee osteoarthritis.When comparing the concentrations of trace elements between urban and rural patients in the structure of knee osteoarthritis,the concentrations of aluminum in the femoral cancellous bone,femoral cartilage,anterior cruciate ligament,meniscus and tibial cartilage in urban patients were significantly higher compared to in rural patients.The concentration of lead in infrapatellar fat pad in urban patients was statistically significantly higher than in rural patients.The concentrations of boron,cadmium and manganese in the structure of knee osteoarthritis in rural patients were higher than in urban patients;The concentrations of chromium,strontium and zinc in knee joint structure of urban patients were higher.Despite the observable differences between urban patients and rural patients in the concentrations of boron,cadmium,manganese,chromium,strontium and zinc,they were not statistically significant.As for the effects of hypertension on the concentrations of trace elements,there were statistically significant differences in magnesium concentrations in anterior cruciate ligament and infrapatellar fat pad between non-hypertensive group and hypertensive group(U = 188,p < 0.05 and U = 116,p < 0.01,respectively).The concentrations of magnesium in anterior cruciate ligament and infrapatellar fat pad in non-hypertensive group were significantly higher than in hypertensive group(201.31 and 167.47 mg / kg dw,61.84 and 40.06 mg / kg dw,respectively).The concentration of strontium in meniscus in non-hypertensive group was significantly higher than in hypertensive group(2.78 and 1.91 mg / kg dw,respectively).The concentrations of aluminum,boron,cadmium and chromium in the structure of knee osteoarthritis in the non-hypertensive group were higher than in the hypertensive group.Though there were obvious differences in the concentrations of aluminum,boron,cadmium and chromium between the non-hypertensive group and the hypertensive group,they were not statistically significant.Considering the effects of diabetes on the concentrations of trace elements in the structure of knee osteoarthritis,the concentrations of magnesium in the anterior cruciate ligament and meniscus in non-diabetic group were statistically significantly higher than in diabetic group.Moreover,the concentrations of manganese in anterior cruciate ligament,meniscus,tibial cartilage and tibial cancellous bone in nondiabetic group were statistically significantly higher than in diabetic group.However,arsenic concentration in the tibia cancellous bone in diabetic group was statistically significantly higher than in non-diabetic group.In the anterior cruciate ligament,the zinc concentration in diabetic group was statistically significantly higher compared to in non-diabetic group.In diabetic group,the concentration of aluminum in knee osteoarthritis was higher than in non-diabetic group,while boron concentration had opposite trend.Although the concentrations of aluminum and boron were different between the two groups,there were no statistically significant differences.3.In the femoral cancellous bone,there were the significant positive correlations in Al-Pb,Al-Zn,B-Mg and Mg-Pb and the significant negative correlations in B-Cu,Cr-Sr and Mn-Sr.In the femoral cartilage,a significant positive correlation between Al and Pb was found,while a significant negative correlation between Mn and Sr was noted.In the anterior cruciate ligament,the significant positive correlations were observed in Al-Pb,Cu-Mn and Sr-Zn,while a significant negative correlation between Mn and Zn was noticed.In the meniscus,there were the significant positive correlations in Al-Pb,Al-Sr,B-Fe and Pb-Zn,while there were the significant negative correlations in B-Cr,Cr-Fe and Mn-Sr.In the tibial cartilage,the significant positive correlations were detected in Al-Pb and B-Fe,the significant negative correlations were found in B-Cr,Cr-Fe and Mn-Sr.In tibial cancellous bone,Al-Pb significant positive correlation was noted,the significant negative correlations were observed in B-Cu,Cr-Fe and Mn-Sr.In the infrapatellar fat pad,Al-Pb and Cu-Zn significant positive correlations were confirmed,B-Cu and Mn-Zn significant negative correlations were noted.Conclusions:1.The results of trace elements(boron,chromium,iron,zinc,copper,magnesium,manganese,strontium,aluminum,arsenic,cadmium and lead)provide a basis for establishing the reference values of these trace elements in the structure of knee osteoarthritis.2.Analysis of the impact of related factors on trace element concentrations in the structure of knee osteoarthritis demonstrated the influence of age,gender,place of residence,hypertension and diabetes.3.There were correlations between trace elements in the structure of knee osteoarthritis.