The present study evaluated the radiological changes in normal and dynamized callus after limb lengthening in New Zealand White rabbits. The aims of the study were to create a lengthening device that allows axial controlled manual dynamization and to examine the effect of the maximal amount of dynamization on the healing, lengthened callus.

10 male domestic white rabbits were divided into two groups (normal distraction group (NDG) and dynamized distraction group (DDG)). Osteotomy was followed by distraction at the same rate and total length in both groups, but in the dynamized distraction group 1 mm manual dynamization was performed for ten minutes three times a day prior to lengthening. Callus formation and lengthening were analysed on the X-ray pictures and on the three-dimensional  CT image respectively. Neither malposition of the pins nor maluninon were found during or after the distraction period. No signifi cant difference was found in the amount of the callus between the NDG and DDG. A lengthening device was created that allows axial  ontrolled manual dynamization and prevents instability in the other two axes and our results showed that this large amount of dynamization did not decrease the formation and quality of the callus.

DOI: 10.17489/biohun/2010/2/01