title: Periarticular bone sites associated with traumatic injury: false-positive findings with In-111-labeled white blood cell and Tc-99m MDP scintigraphy.
abstract: The authors evaluate the reliability of combined indium-111-labeled white blood cell (WBC) and technetium-99m methylene diphosphonate (MDP) bone scan interpretations at sites of suspected periarticular osteomyelitis with radiographic evidence of adjacent traumatic arthropathy. A review of all orthopedic patients who underwent In-111 WBC-Tc-99m MDP scintigraphy over a 7-year period revealed a subset of 32 such cases that also included results of bone-biopsy cultures. Twenty-eight patients had a history of traumatic intraarticular injury, and four had periarticular fracture malunion or nonunion. Compared with intraoperative culture results, blinded In-111 WBC-Tc-99m MDP scan interpretations included four true-positive, 17 true-negative, and 10 false-positive results, and one false-negative result. The predictive values for positive and negative scans were 28% and 94%, respectively. A high prevalence of false-positive In-111 WBC-Tc-99m MDP scans may occur at periarticular sites of patients with associated traumatic arthropathy. This reduces the specificity of this technique for osteomyelitis, making culture confirmation of positive scans necessary. A negative scan is highly predictive of negative culture results at these sites.
authors.affiliation: Department of Radiology, University of Iowa College of Medicine, Iowa City.
authors.forename: J E
authors.initials: JE
authors.lastname: Seabold
authors.forename: R J
authors.initials: RJ
authors.lastname: Ferlic
authors.forename: J L
authors.initials: JL
authors.lastname: Marsh
authors.forename: J V
authors.initials: JV
authors.lastname: Nepola
mesh_terms: D000328:Adult; D000368:Aged; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D005189:False Positive Reactions; D005260:Female; D050723:Fractures, Bone / Q000150:complications; D005599:Fractures, Ununited / Q000150:complications; D006801:Humans; D007205:Indium Radioisotopes; D007596:Joints / Q000293:injuries*; D007962:Leukocytes; D008297:Male; D008875:Middle Aged; D010019:Osteomyelitis / Q000150:complications / Q000000981:diagnostic imaging* / Q000453:epidemiology; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013669:Technetium Tc 99m Medronate
chemical_list: D007205:Indium Radioisotopes; D013669:Technetium Tc 99m Medronate