Database results
Results from the search strategy demonstrated that the database with the most publications was Scopus (570), followed by Web of Science (341), and PubMed (243). The greatest number of identical articles was through the combined database of Web of Science and Scopus (Figure 1). Finally, a total of 117 related articles were included. Of these, the database with most publications on the meta-analysis of PJI was Scopus, followed by Web of Science and PubMed. Web of Science and PubMed had most missed articles compared with other databases (Figure 2 and 3).
Characteristics of meta-analysis of PJI research
General data
Among the 117 meta-analysis articles, the earliest publications were from 2007. The greatest number of articles were published in 2018 (24), followed by 2017 and 2019 (21 each). The trend line indicates an annual increase in the number of articles (Figure 4). One hundred and fourteen articles were in English, and three other articles were each published in Chinese, German, and Persian. In all meta-analyses, the number of studies included ranged from 4 to 203, with the highest number 12 (n = 11 publications), followed by eight (9) as well as six and eleven studies (8 each).
Countries
Nineteen countries published meta-analyses on PJI. Of these, China was the most productive country, with all publications stemming from 15 cities/provinces. The highest number of articles originated from Shanghai, followed by Beijing (Figure 5). The country with the second-highest number of publications on PJI was the US, followed by the UK (Table 1).
Institutions
A total of 76 institutions made contributions to this field. The institution with the greatest number of publications was the University of Bristol with 11 papers, followed by Shanghai Sixth People’s Hospital (8). The Rothman Institute and General Hospital of the Chinese People’s Liberation Army were third, with each publishing five research articles. Fourteen institutions published more than one paper, with 50% originating from China (Table 2).
Authors
The number of authors of a single article ranged from 2 to 37. The largest number of collaborating authors was four (27), followed by six (25) and 5 authors (20; Table 3). The author with most first authorships was Setor K. Kunutsor (10), followed by Xinhua Qu (3). Ten first authors wrote more than one meta-analysis, with 50% published by research institutes in China (Table 4).
Journals
Meta-analysis studies were published in 54 different journals. The journal with most publications was the Journal of Arthroplasty, with 15 publications. The Journal of Bone and Joint Surgery ranked second with eight publications, whereas PLoS ONE was third with seven. Nineteen journals had more than one publication (Table 5). In 2019, an impact factor was available for 42 journals. The list of top 10 journals with the highest impact factors are shown in Table 6.
From all publications, the date of receipt was available for 89 papers, whereas the date of acceptance for 85, and the date of publication for 72. From the date of receipt to acceptance, information was available for 65 articles, with the average number of days until acceptance 95.69. Among these 65 articles, 11 journals had more than two publications, whereas four journals had an average acceptance time of fewer than 100 days. There are the Journal of Orthopaedic Surgery and Research (68 days), followed by the Journal of Hospital Infection (82 days), Journal of Clinical Microbiology (83 days), and Journal of Arthroplasty (86 days).
The average number of days from acceptance to publication was 56.52 (66 papers). From receipt to online publication, the average number of days was 157.48 (69). There were six articles accepted in less than 30 days after submission. The journal with the shortest acceptance time was the Journal of Clinical Medicine (16 days), followed by the Journal of Computational and Theoretical Nanoscience (18 days), Journal of Clinical Medicine (22 days), Journal of Arthroplasty (23 days), Journal of Orthopaedic Surgery and Research as well as Medical Science Monitor (27 days each).
Most-cited publications
From Google scholar, citation information was available for 103 meta-analyses. Forty-one articles were cited more than 20 times, with the highest number in 2014 (9), followed by 2013, 2016, and 2017 (7 each). The most cited article was published by Al Buhairn et al. [12] (264), followed by Parvizi et al. [13] (235; Table 7).
Search algorithm and keywords
One hundred and two meta-analyses were retrieved from the search strategy, which were exported to Microsoft Excel. All keywords or MeSH were combined. PJI-related keywords were 196, followed by diagnosis (179), prevention (82), risk factor (74), and outcome (60). All keywords are presented in Supplementary 1. From 71 publications, 389 keywords were exported. Periprosthetic joint infection (41) was the most commonly used keyword, followed by meta-analysis (29) and total knee arthroplasty (20; Table 8).
Database and software
After combining all databases from 116 articles, there was a total of 52 databases. Embase was the most described database (101), followed by MEDLINE (80), and Cochrane (74; Table 9). Three databases were most frequently searched (40), followed by four (22), and five (16). The most combined database group was Cochrane Library + Embase + MEDLINE/PubMed (10), followed by Embase + MEDLINE (6), and Cochrane Library + Embase + MEDLINE + Web of Science (5).
For the meta-analysis, 13 software was exported from 106 articles. The most commonly used software was STATA (43), followed by REVMAN (25), and Meta-Disc (21).
Subject
Location
Information on the site of prosthetic joint infection from the included meta-analysis were found in 112 papers. The location with the highest number was the knee (93), closely pursued by the hip (90), shoulder (23), elbow (16), and ankle (3).
Diagnosis of PJI
From 40 diagnosis-related meta-analyses, 72 tests were related to preoperative examination, followed by intraoperative methods (12), and test prior to reimplantation (14). Synovial fluid alpha-defensin had highest pooled sensitivities in the list of preoperative examinations, pursued by serum IL-6 and bone scintigraphy. From all intraoperative examinations, tissue polymerase chain reaction (PCR) was the most sensitive method, followed by sonicate fluid into blood culture bottles (BCB) and PCR. Tissue culture was the most sensitive method before reimplantation, followed by the percentage of polymorphonucleocytes in synovial fluid (PMN%), and synovial fluid culture (Table 10). The most frequent diagnostic method used was synovial fluid (16), followed by imaging (10), and periprosthetic tissue (7; Figure 6).
Risk factor and prevention
Twenty-three articles described 64 possible risk factors. The location of the risk factor was outlined in 20 studies, with the majority in the hip and knee (Table 11). Nine preventive measures were described in 17 articles, with all focusing on the hip and knee (Tale 12).
Comparative analysis
There were 26 comparative analytic studies from all meta-analyses, with most related to the hip and knee (11), followed by the hip as well as the hip and knee (7 each). There was no statistical difference found in 13 comparison studies (Table 13).