TABLE 1 

Medical and orthopedic surgical history and PJI presentationc

CharacteristicdSCVb
Yes (n = 38)No (n = 75)P value
Demographic factors
    Age in yr, median (range)64 (25–85)63 (36–84)0.49
    Female sex16 (42.1)31 (41.3)1
    Diabetes mellitus10 (26.3)20 (26.7)0.97
    Rheumatoid arthritis by ACR criteria1 (2.6)5 (6.7)0.66
    Rheumatoid or inflammatory arthritis3 (7.9)11 (14.7)0.38
    CKD2 (5.3)6 (8.0)0.72
    Immunosuppressive therapy4 (10.5)12 (16.0)0.57
    Joint infected0.98
        Knee25 (65.8)46 (61.3)
        Hip8 (21.1)16 (21.3)
        Shoulder3 (7.9)8 (10.7)
        Elbow2 (5.3)5 (6.7)
Orthopedic history
    Joint age in days, median (range)1,295 (216–13,712)646 (23–11,883)0.007
    Prior arthroplasty revision32 (84.2)52 (70.3)0.17
    Time since last surgery in days, median (range)743 (31–10,030)306 (20–8,686)<0.0001
    Cemented arthroplasty33 (86.8)60 (80.0)0.44
    Antibiotic-loaded cement in placea8 (44.4)16 (39.0)0.78
    Aminoglycoside in cementa7 (38.9)8 (19.5)0.19
PJI history
    Sinus tract11 (28.9)19 (25.3)0.82
    Duration of PJI symptoms in days, median (range)491 (14–2,306)165 (2–1,656)0.0003
    Prior surgery for this PJI23 (60.5)28 (37.3)0.03
    Cumulative antibiotic days in prior 6 mo, median (range)66 (0–180)13 (0–180)0.37
    Receiving 120 or more days of antibiotics in prior 6 mo16 (42.1)17 (22.7)0.048
    Serum WBC in 109 cells/liter, median (range)7.4 (4.5–11.7)7.9 (3–23.3)0.13
    Serum ESR in mm/h, median (range)46 (5–111)43 (3–123)0.54
    Serum CRP in mg/liter, median (range)23 (5–222)44 (3–269)0.2
    Preoperative SF aspirate26 (68.4)51 (68.0)
        SF WBC in cells/µl, median (range)28,574 (8,175–155,000)44,275 (629–1,071,472)0.13
        SF neutrophil %, median (range)88 (79–98)91 (51–100)0.84
  • a Excluding 54 subjects for whom the presence or absence of antimicrobials in the cement could not be ascertained.

  • b All values indicate number (%) unless otherwise specified.

  • c Continuous variables were compared using Wilcoxon rank sum test, and categorical variables were compared using Fisher’s exact test.

  • d Abbreviations: ACR, American College of Rheumatology; CKD, chronic kidney disease; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; SF, synovial fluid; WBC, white blood cell count.