Fig. 5.

Radiographs of defects treated with 5.5 μg of rhBMP-2 and reverse dynamization. The defects were stabilized initially with an external fixator of very low (25.4-N/mm) or low (114-N/mm) stiffness. After 2 weeks, the stiffness was increased to 254 N/mm (high stiffness) in the groups receiving reverse dynamization (RD). Defects were monitored by weekly radiographs (Fig. 5-A). Figure 5-B shows a close-up of the radiographs at 4 and 8 weeks, highlighting the radiolucent discontinuity that is present in all but the reverse dynamization group in which the initial fixation was of low stiffness (low stiffness RD).