You are looking at 1 - 1 of 1 items for
- Author or Editor: Lars F. Theyse x
- Refine by Access: All Content x
Objective—To quantitatively assess distractioninduced bone formation in a crural lengthening model in dogs by use of delayed-image bone scintigraphy.
Animals—12 mature Labrador Retrievers.
Procedure—Dogs were randomly allocated to 1 of 3 groups. A circular external skeletal fixation system was mounted on the right crus of each dog. Osteotomy of the distal portion of the tibia and fibula was performed in groups 1 and 2 and was followed by a lengthening procedure of 10 mm in the first group only. The third group served as sham-operated controls. Delayed-image bone scintigraphy with technetium-99m hydroxy methylene diphosphonate was performed 2, 4, and 6 weeks after surgery. Delayedimage–to–region-of-interest, delayed-image–to–crural, and delayed-image–to–femoral scintigraphic activity ratios were calculated. New bone formation was quantified by use of densitometric image analysis, and values for the scintigraphic ratios were compared.
Results—In the distraction and osteotomy groups, delayed-image–to–region-of-interest and delayedimage-to-crural ratios increased significantly. Although densitometric image analysis revealed increased bone formation after distraction, the region-of-interest ratios and crural ratios were similar in both groups. All dogs had increased delayedimage–to–femoral ratios.
Conclusions and Clinical Relevance—Delayed-image bone scintigraphy ratios were not effective at differentiating between the amounts of distraction-induced bone and osteotomy-induced bone. Metabolic bone activity in the adjacent femur was increased as a consequence of circular external skeletal fixator placement. Delayed-image bone scintigraphy was not adequately sensitive to quantitatively monitor bone formation but may be useful as an early predictor of bone healing.