Traumatic epiphyseal separation was produced in the young rabbit weighing about 1 kg, and the type of injuries according to Salter aad Harris method and location of the cleavage line within the epiphysis were studied radiologically and histologically, with the following result.
1. At the distal femu{ and the distal radius, the hyperextension force produced predominantly the Type I injury. fa 96% and 75% respectively, while the rotation force resulted mainly in the Type ~ j . in 65% and 90% respectively. The lateral bending produced almost the equal ratio of the Type j and j:
2. Of all the injuries, the cleavage line within the epiphyseal growth plate could be located in the hypertrophying cartilage cell Iayer in 58.8%, in that it was 76% in the hyperextension group, 51% in the Iateral bending group, .and 49% in the rotation group.
3. The results of the above experiment have shown that the external violence of severe and complicated nature tended to produce the Type j injury, and the line of cleavage thus produced had the tendency to be located out of the hypertrophying cell Iayer, the common site of its separation.
|