An experimental work has been carried out on prevention of fiseal bonebridges formation by means of interposing autologus periosteum graft, bringing up the followingobjetives: 1) To achieve a barrier which can prevent the communication betweenepiphyseal and metaphyseal vessels, and 2) To study the condrogenic potencial of periosteum.A total of 48 rabbits have been used, arranged in three series of four groups each,acording to the moment of sacrifice in the 1st, 2nd, 4th and 8 t h weeks. They were all operatedon the right femur. In the control serie an extirpation of 1/3 of the outer and distalgrowth plate was carried out, while in the experimental series the created defect was filledup with a free periosteum graft. All the specimens were studied macroscopically, radiologicallyand histologically. As conclusions, the periosteum used as a free graft: 1) In the firstweeks act like a pasive barrier in physeal lesions, 2) It has also condrogenic capacity in thefirst weeks and, 3) On large follow-up studies, the periosteum do not seems to be a efectivematerial to prevent physeal bone bridges.

An experimental work has been carried out on prevention of fiseal bonebridges formation by means of interposing autologus periosteum graft, bringing up the followingobjetives: 1) To achieve a barrier which can prevent the communication betweenepiphyseal and metaphyseal vessels, and 2) To study the condrogenic potencial of periosteum.A total of 48 rabbits have been used, arranged in three series of four groups each,acording to the moment of sacrifice in the 1st, 2nd, 4th and 8 t h weeks. They were all operatedon the right femur. In the control serie an extirpation of 1/3 of the outer and distalgrowth plate was carried out, while in the experimental series the created defect was filledup with a free periosteum graft. All the specimens were studied macroscopically, radiologicallyand histologically. As conclusions, the periosteum used as a free graft: 1) In the firstweeks act like a pasive barrier in physeal lesions, 2) It has also condrogenic capacity in thefirst weeks and, 3) On large follow-up studies, the periosteum do not seems to be a efectivematerial to prevent physeal bone bridges.