ABSTRACT
Objective@#To investigate and compare the capability of metagenomic next-generation sequencing (mNGS) in detecting pathogens and diagnosing of periprosthetic joint infection (PJI) from synovial fluid and sonicate fluid of patients who underwent revision arthroplasty.@*Methods@#Thirty-five consecutive patients who underwent revision arthroplasty from May 2018 to November 2018 were included prospectively. There were 22 males and 13 females, 11 hip revisions and 24 knee revisions. All the patients were divided into the PJI group and aseptic loosening (AL) group. Synovial fluid and sonicate fluid of the explanted prostheses were obtained for microbiological culture and mNGS tests. Periprosthetic tissues were only collected for culture. Synovial fluid of three patients undergoing primary arthroplasty been treated by sonication as the negative control group concurrently. Comparisons of microbiological results and diagnostic value from mNGS and culture tests were performed.@*Results@#In the 13 culture-positive PJI patients, mNGS results of synovial fluid were positive in 12 cases, while culture and mNGS results were completely consistent at species level in 7 cases, consistent at the genus level in 1 case. mNGS results of sonicate fluid were positive in 13 cases, while culture and mNGS results were completely consistent at species level in 9 cases, consistent at the genus level in 1 case. In 7 culture-negative PJI patients, 6 cases had consistent mNGS results at species level both from synovial fluid and sonicate fluid, however, one case had positive mNGS result only from sonicate fluid. All culture results and mNGS results of synovial fluid were negative in all 15 AL patients, however, mNGS results of sonicate fluid was positive in 1 AL case. Cultures and mNGS results were negative in all three pairs of negative-control samples. In all 70 samples, mNGS detected 24 pathogens in sonicate fluids and 22 pathogens in synovial fluids. There was no significant difference in number of raw reads and human reads ratio between mNGS of sonicate fluid and synovial fluid. mNGS of sonicate fluid generated significantly higher number of microbial reads and of stringently mapped reads of pathogen in species-level than that of synovial fluids. There was no significant difference in diagnostic sensitivity of PJI between mNGS of sonicate fluids and synovial fluids (90.0% vs 100.0%). Both of them were significantly higher than that of culture of synovial fluid, periprosthetic tissues. Diagnostic sensitivity of sonicate fluid mNGS was not significantly higher than that in culture of sonicate fluid (65%). The specificities were similar among various microbiological testing methods.@*Conclusion@#mNGS of either synovial fluid or sonicate fluid from patients who underwent revision arthroplasty can be used to detect the presence of pathogens effectively and diagnose PJI accurately. mNGS can identify more pathogens and generate a higher number of pathogenic reads from sonicate fluids than synovial fluid. mNGS of synovial fluids has met the clinical diagnostic demands for most PJI patients. mNGS of sonicate fluid could be applied in some cases.
ABSTRACT
Objective To evaluate the effect of anterior cervical fusion or non-fusion surgery for the treatment of Hirayama disease.Methods The patients with Hirayama disease who underwent anterior cervical surgery in our hospital from July 2008 to December 2015 were retrospectively enrolled in this study.These cases were divided into two groups:fusion group(11 cases)and non-fusion group(12 cases).In fusion group,there were 9 males and 2 females,with an average age of 17.92±0.61 years(range,15-29).In the non-fusion group,there were 10 males and 1 female,with an average age of 19.18±1.14 years(range,15-23).Muscle strength,muscular atrophy,and the Michigan score for hand function were compared between the two groups preoperatively and postoperatively.The indexes such as arc cervical physiological curvature index,the maximum flexion angle,the maximal range of motion(ROM),flexion ROM of adjacent segments of lower(cervical vertebra were measured from the X-ray of the two groups,and the cross-sectional area of spinal cord was measured and compared on neutral position MRI.Results There were no significant differences between the two groups in grip strength,preoperative hand function Michigan score,cervical physiological(curvature index,the maximum flexion angle,the maximal ROM,flexion ROM of adjacent segments of lower cervical vertebra,and cross-sectional area of spinal cord on neutral position MRI(P>0.05).Patients in fusion group were followed up for 38-103 months with an average of 59.73±5.57 months,while patients in non-fusion group were followed up for 40-95 months with an aver-age of 56.25±4.57 months.Clinical outcomes:At the last follow-up,the finger tremor and cold paralysis were alleviated in all patients,but the symptoms in fusion group and non-fusion group were not completely disappeared in 2 and 3 cases,respectively.The grip strength of fusion group(preoperative 17.14±6.09,postoperative 17.47±5.64)and the non-fusion group(preoperative 17.75±5.49,postoperative 17.40±4.58)were not significantly improved compared with preoperative(P>0.05).The Michigan score for hand function of fusion group(preoperative 10.27±0.41,postoperative 6.64±0.24)and the non-fusion group(preoperative 9.25±0.35,postoperative 6.83±0.24)were significantly improved compared with preoperative(P<0.05).There was no significant difference in postoperative Michigan score between the two groups(P>0.05).Radiological outcomes:The cervical physiological curvature index and cross-sectional area of the spinal cord of the two groups increased after operation,while the maximum flexion angle,the maximal ROM decreased.There was no significant difference in these indexes between the two groups postoperatively(P>0.05).The spinal cord had no compression on flexion MRI.The cross-sectional area of C4-C7 spinal cord in Neutral MRI were significantly increased at C6 and C7 levels in both groups.There was no significant difference in the cross-sectional area of C4-C7 spinal cord between the two groups postoperatively(P>0.05).Two cases of internal fixation loosening occurred in non-fusion group 3 years after the operation,while there were no cases of loosening in the fusion group.Conclusion Anterior cervical fusion or nonfusion surgery can limit excessive cervical kyphosis in patients with Hirayama disease,reduce atrophy of compressed cervical spinal cord,and alleviate the disease progress of muscular atrophy of the distal upper limb.It can be selected as a treatment method for Hirayama disease.However,there is a risk of internal fixation loosening in non-fusion cases,and also a risk of adjacent segment degeneration in fusion cases.The appropriate cases should be selected carefully for surgery.
ABSTRACT
Objective To investigate and compare the capability of metagenomic next?generation sequencing (mNGS) in detecting pathogens and diagnosing of periprosthetic joint infection (PJI) from synovial fluid and sonicate fluid of patients who un?derwent revision arthroplasty. Methods Thirty?five consecutive patients who underwent revision arthroplasty from May 2018 to November 2018 were included prospectively. There were 22 males and 13 females, 11 hip revisions and 24 knee revisions. All the patients were divided into the PJI group and aseptic loosening (AL) group. Synovial fluid and sonicate fluid of the explanted pros?theses were obtained for microbiological culture and mNGS tests. Periprosthetic tissues were only collected for culture. Synovial fluid of three patients undergoing primary arthroplasty been treated by sonication as the negative control group concurrently. Com?parisons of microbiological results and diagnostic value from mNGS and culture tests were performed. Results In the 13 culture? positive PJI patients, mNGS results of synovial fluid were positive in 12 cases, while culture and mNGS results were completely consistent at species level in 7 cases, consistent at the genus level in 1 case. mNGS results of sonicate fluid were positive in 13 cas?es, while culture and mNGS results were completely consistent at species level in 9 cases, consistent at the genus level in 1 case. In 7 culture?negative PJI patients, 6 cases had consistent mNGS results at species level both from synovial fluid and sonicate fluid, however, one case had positive mNGS result only from sonicate fluid. All culture results and mNGS results of synovial fluid were negative in all 15 AL patients, however, mNGS results of sonicate fluid was positive in 1 AL case. Cultures and mNGS results were negative in all three pairs of negative?control samples. In all 70 samples, mNGS detected 24 pathogens in sonicate fluids and 22 pathogens in synovial fluids. There was no significant difference in number of raw reads and human reads ratio between mNGS of sonicate fluid and synovial fluid. mNGS of sonicate fluid generated significantly higher number of microbial reads and of stringent?ly mapped reads of pathogen in species?level than that of synovial fluids. There was no significant difference in diagnostic sensitivi?ty of PJI between mNGS of sonicate fluids and synovial fluids (90.0% vs 100.0%). Both of them were significantly higher than that of culture of synovial fluid, periprosthetic tissues. Diagnostic sensitivity of sonicate fluid mNGS was not significantly higher than that in culture of sonicate fluid (65%). The specificities were similar among various microbiological testing methods. Conclusion mNGS of either synovial fluid or sonicate fluid from patients who underwent revision arthroplasty can be used to detect the pres?ence of pathogens effectively and diagnose PJI accurately. mNGS can identify more pathogens and generate a higher number of pathogenic reads from sonicate fluids than synovial fluid. mNGS of synovial fluids has met the clinical diagnostic demands for most PJI patients. mNGS of sonicate fluid could be applied in some cases.