[The unilateral axial dynamic fixator study of its biomechanical property and clinical application]

The home made UADF after Bastiani's pattern was mechanically tested in our lab on fracture of cadaveric femurs. For comparison, the same test was also carried out with conventional semicircular external fixator. The results showed that the rigidity and stability of fixation closely related with the diameter of the bone-pin used. The diameter of the treated pins used in UADF was one time larger than that of the round pin used in conventional semicircular external fixator. The compression rigidity of the former frame was 3.5 times stronger than that of the latter one; the extent of displacement of the fragments happened in the former frame was much less than that occurred in the latter one. Clinical Application of UADF. on fracture of tibia and fibula in 31, of femur in 8, knee arthrodesis and osteotomy of tibia and fibula one in each, brought bony healing on successfully. It is apparent that the UADF is multifunctional, universal and adaptable in use, leading to success.