The effects of intraosseous infusion on the growth plate in a nestling rabbit model.

STUDY

OBJECTIVE

The objective of this study was to test the hypothesis that saline or bicarbonate infusion does not damage the growth plate in a nestling rabbit model.

SETTING

Animal laboratory.

DESIGN

In this prospective study, 22 tibias from nestling rabbits were randomized into control, puncture-only, physiologic saline, or bicarbonate infusion groups and killed three and five days after treatment for evaluation of injury.

MEASUREMENTS: Bone injury was evaluated by microradiograph and by decalcified and undecalcified histology.

RESULTS

Radiographs demonstrated loss of trabecular (ie, calcified) bone after infusion of both saline and bicarbonate solutions. Although no histologic damage to the cell lines of the growth plate was seen, newly formed bone trabeculae were seen in both infusion groups, suggesting injury and repair at sites of infusion. These findings were absent in control and puncture-only groups. No histologic or radiographic differences were seen between saline and bicarbonate infusions.

CONCLUSION

The nestling rabbit provides a good animal model for evaluating the effects of intraosseous infusion on growing long bones and cartilage. Saline and bicarbonate infusions did not damage morphologically the metaphyseal growth plate but did cause loss of bone trabeculae that support the growth plate. The injury appeared to be repaired rapidly in these nestling rabbits.