Changes in the growth of the apophysis of rabbits were studied by giving continuous tonus stimulation to it through auto-muscles, and based on the results of this study, the following conclusion was reached about the etiology of the so-called apophyseopathy.
1) Hypertrophy at the part where the tendon inserts to bone (tendon cartilage region) began in one week. Hypertrophy, deformity, and hyperplasia in the tracted direction were observed up to the 25 th week, but no remarkable changes were noted after 30 th week.
2) Lateral and ventral bending deformity appeared at the diaphysis of the corpus ossis ischii. More marked deformity and hyperplasia were observed in the procesus lateralis ischiadicum inserted to the tendon than in the tuber ischiadicum directly inserted to the muscle.
3) X-ray examinations revealed the early appearance of the apophyseal nucleus on the treated side, the gradual falling into irregularity of the boundary between the bone and the cartilage, the aspects of abnormal hypertrophy of the tendon cartilage region, and the aspects of segmentation and loosening like small fragments of the bone in the apophyseal nucleus at the end of 2 weeks. After 20 th week, light and dense bone image, transparent zone, and the island-like bone trabecula were observed.
4) Histological examinations manifested the onset of hypertrophy and proliferation of the tendon-cartilage layer and the gradual transition to the growing cartilage layer. As days went by, intense proliferation of chondrocytes in the tendon-cartilage layer and growing cartilage layer, separation of chondrocyte into the bone marrow, formation of cartilageisland, hyperplasia owing to the mechanism of vigorous ossification by these chondrocytes were observed.
5) Apophysis of young rabbits showed remarkable changes as described above, but that of the adult showed almost no changes.
6) Hyperplasia of apophysis can be produced by giving the continuous stimulation through auto-muscles, but does not grow unlimitedly. Its growth stops when the growing cartilage layer closes, but the growing cartilage layer does not always close so early.
7) Genetic mechanisms of epiphyseopathy and apophyseopathy seems to have to be considered individually since there is a difference of functional and pathologico-anatomical relationship, especially of the insertion of muscle and tendon.
8) The so-called apophyseopathy-liked condition could be provoked by giving continuous tonus stimulation to tuber ischiadicum non-physiologically through auto-muscles, and this suggests the etiology of apophyseopathy such as Osgood-Schlatter disease, acromial apophyseopathy, humerus epicondyle apophyseopathy, tuber ischiadic apophyseopathy, and calcaneal apophyseopathy. It may be surmised that abnormal muscle tonus is the major cause of apophyseopathy.
抄録全体を表示