家兎大腿四頭筋が注射及びギプス固定によつて起る影響について

(筋の引張破断試験ならびに組織学的検討)

抄録

In young rabbits (500-600 g) receiving 3 consecutive daily injections of chloramphenicol (CP) into the quadriceps muscle or reard under immobilization of the hind leg with a cast the tension and histologic changes of the quadriceps muscle were examined in course of time with the following results:
1. Relatively localized fibrosis and the presence of excessive fat cell were found in the quadriceps muscle injected with CP.
2. Marked atrophy of musculature occurred in the quadriceps muscles of the rabbits with an immobilized hind leg with a cast. The longer the duration of cast immobilization was, the stronger this changes was.
3. The rectus femoris muscle was found in the tensile-breaking test to rupture at the muscle-tendon region approximately 10 cm proximal to the patella.
4. The stress-strain diagram at rupture of the rectus f emoris muscle gave value varying from 2.0 to 3.0 cm. When reached 25 to 30% of the whole length of the muscle, it developed complete rupture.
5. Tension of the rectus femoris muscle reached a peak after 8 weeks when fibrosis and the presence of excessive fat cell were marked. It was also the strongest in the strongest in the animals subjected to 8 weeks' cast immobilization, in which atrophy and fibrosis of musculature were histologically confirmed.
6. The present study suggested the relation between fibrosis, atrophy, fatty degeneration, etc. of musculature and the development of muscular contracture. Accordingly, it will be desirable to avoid such a treatment as causing fibrosis of musculature as far as possible for prevention of muscular contracture.