Rapid normalization of osseous FDG uptake following traumatic or surgical fractures

Abstract

It is known that following a traumatic fracture or surgical intervention, bone scintigraphy reveals positive results for an extended period of time, posing a challenge when evaluating patients for possible malignancy or superimposed osteomyelitis. Previous reports indicate that acute fractures can also result in increased fluorine-18 fluorodeoxyglucose (FDG) accumulation and therefore cause difficulties when patients are evaluated for other indications by FDG-PET. The purpose of this study was to assess the pattern and time course of abnormal FDG uptake following traumatic or surgical fracture. A total of 1,517 consecutive patients who underwent whole-body FDG-PET imaging were retrospectively studied. A history of fractures or orthopedic intervention was obtained from an interview prior to scanning. The FDG-PET results were compared with the results of other imaging studies, including bone scans, radiographs, CT, and MRI, as well as surgical pathology reports. Thirty-seven patients with a known date of traumatic or surgical fracture were identified. Among these, 14 had fractures or surgery within 3 months prior to FDG-PET, while 23 had fractures or surgical intervention greater than 3 months prior to FDG-PET. FDG-PET showed no abnormally increased uptake at the known fracture or surgical sites in 30 of these patients. Notably, in the 23 patients with fractures more than 3 months old, all but one showed no abnormally increased uptake. Furthermore, the positive FDG uptake in this exception was a result of complicating osteomyelitis. In the 14 patients with a history of fracture less than 3 months old, only six had abnormally increased FDG uptake. Following traumatic or surgical fractures, FDG uptake is expected to be normal within 3 months unless the process is complicated by infection or malignancy.

Current Molecular Imaging of Spinal Tumors in Clinical Practice

“…In bone scintigraphy, increased uptake persists for many months after fracture and depends on the site of injury (90). Although the duration of abnormal 18F-FDG uptake in benign fractures is unknown, Zhuang et al (95) reported that 18F-FDG uptake rapidly decreased with time after fracture and that it should be normal within a maximum of 3 months. Shon and Fogelman (90) reported that the most intense 18F-FDG uptake was observed when MI by PET was performed 17 days after fracture, among the four-case series where imaging was performed from 17 days to 8 weeks.…”

Rol del PET/CT con 18FDG en patología no neoplásica

“…Sin embargo, en los casos donde hay captación aumentada de FDG, no permite diferenciar entre ambas causas, debiendo utilizarse otro método de estudio para su diferenciación 34 . Entre las causas de falsos positivos para las infecciones óseas se encuentran artritis inflamatorias, fracturas, reparación ósea y cirugías recientes, ya que pueden presentarse como áreas focales de aumento del metabolismo 35 .…”

Osteomyelitis and Arthritis

“…Increased FDG accumulation in PET is also associated with inflammatory arthritis, fractures, normally healing bone and degenerative changes (14)(15)(16). However in contrast to bone scintigraphy, FDG PET rapidly normalizes after traumatic or surgical fractures (14,16) as fibroblast predominate in normally healing bone, and FDG uptake quickly subsides 4 months after surgery (17).…”

“…However in contrast to bone scintigraphy, FDG PET rapidly normalizes after traumatic or surgical fractures (14,16) as fibroblast predominate in normally healing bone, and FDG uptake quickly subsides 4 months after surgery (17). The healing process shows most of the cells that are present in inflammation (18).…”