A study on the effects of axial compressive external fixation on fracture-healing in goats / 第三军医大学学报

ABSTRACT

Transverse fracture was inflicted to the tibia of goats and specially designed external fixator was used for fixation to observe the relationship of different intensity of compres-sive force with fracture-healing.It was found in vitro test that the external fixator possessed less effect of stress protection.X-ray examination revealed that the stronger the compressive force was applied,the later the external callus would appear and the less amount of external callus would form.In the 6th week after fracture,the fracture line became oblierated in cases with mild compression while a transparent line in the external callus could be seen on x-ray films in those cases with heavy compression.Though there was no significant difference of the parameters of torsionmetry among different groups,the strength of the healed fracture with mild compression was nearer to the strength of a normal bone than that with heavy compression.Histo-logical examination revealed that all the bone unions belonged to secondary bone healing and bone callus became less matured along with the increase of compressive force.