Painful infection at the site of hip prosthesis: CT imaging.
OBJECTIVE
To prospectively determine the accuracy of computed tomography (CT) in the detection of painful infection at the site of hip prosthesis before surgery.


METHODS
Helical CT examinations of hip prostheses were prospectively performed before surgery after a standard clinical and radiologic examination of 65 patients. CT scans and conventional radiographs were reviewed for periprosthetic bone abnormalities, and CT scans were reviewed for periprosthetic soft-tissue abnormalities (joint distention, fluid-filled bursae, and fluid collection in muscles and perimuscular fat). Patients subsequently underwent revision arthroplasty within 1 month, and infection was diagnosed in 12 (19%) patients.


RESULTS
Infection was detected clinically in 25% of patients. Periprosthetic bone abnormalities did not allow differentiation of infection from complications not related to sepsis, except for periostitis, with 100% specificity but only 16% sensitivity. Soft-tissue findings were accurate for detection of infection, with 100% sensitivity and 87% specificity. Fluid collection in muscles and perimuscular fat had a 100% positive predictive value, and absence of joint distention had a 96% negative predictive value.


CONCLUSIONS
CT is accurate in the diagnosis of painful infection at the site of a hip prosthesis on the basis of soft-tissue findings, whereas periprosthetic bone abnormalities are not useful.
Cyteval
Catherine
C
Department of Radiology, Hôpital Lapeyronie, 371 avenue du Doyen Gaston Giraud, 34295 Montpellier Cedex 5, France. c-cyteval@chu-montpellier.fr
Hamm
Vivien
V
Sarrabère
M Pierre
MP
Lopez
F Michel
FM
Maury
Philippe
P
Taourel
Patrice
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed