Qualitative and Quantitative Scintigraphic Imaging to Predict Fracture Healing

Abstract

SummaryPurpose: Evaluate the value of 24- hour postoperative quantitative bone scintigraphy to identify devascularized fragments and predict delayed fracture bridging in canine clinical patients; to determine the effect of fracture type, fixation type, age, sex, and weight on fracture bridging and the quantitative scintigraphic ratios; and to evaluate the relationship between qualitative scintigraphic assessment and quantitative scintigraphic ratios. Methods: Forty-two adult dogs, with diaphyseal long bone fractures treated with minimally invasive biological or invasive surgical techniques, were evaluated with 24-hour postoperative bone scintigraphy and six and 12 week postoperative radiographs. Fractured bones were classified as simple, moderately multiple, or severely multiple. Bone scintigrams were qualitatively and quantitatively analyzed. Radiographs were made at six and 12 weeks after the operation and graded as fracture gap(s) bridged or not bridged with bone opacity material. The data was evaluated statistically to determine the relationship between age, sex, and weight of the dogs, fracture type, fixation type, and results of scintigram analysis to fracture bridging at six and 12 weeks. Results: Fourteen of the 42 fractures were bridged at six weeks after the operation and 33 at 12 weeks. Prediction of fracture healing was not possible. There was not any statistical relationship of fracture type, fixation, sex, nor weight to bridged fractures or non-bridged fractures at six and 12 weeks. There was a trend toward more of the fractures with multiple fragments treated with minimally invasive biological techniques to be bridged by 12 weeks when compared to similar fractures treated with invasive techniques. The mean age of dogs with bridged fractures at six and 12 weeks was significantly lower than the mean age of dogs with non-bridged fractures at six and 12 weeks. Qualitative scintigraphic assessment scores were not significantly related to the quantitative scintigraphic ratios or to fracture bridging. Conclusions: Neither qualitative nor quantitative assessment of bone scintigrams 24 hours after the operation could be used to predict fracture bridging at six or 12 weeks postoperatively.The value of 24-hour postoperative qualitative and quantitative bone scintigraphy to predict fracture bridging by 12 weeks in canine clinical patients with diaphyseal long bone fractures was evaluated. Neither qualitative nor quantitative assessment of bone scintigrams 24 hours after the operation could be used to predict fracture bridging by 12 weeks.Supported in part by a grant from the AO Vet Centre, Zurich, Switzerland.