Experimemtal Investigations Into the Healing of Fractures

T h e healing of fractures has aroused great interest ever since the days of Galen and Hippocrntes and has been the object of numerous investigations.I n 1940, according to Urisf and Johnson, thcrc were inore than 1.000 publications on this subject and this figure has since heen considerably increased.T h e questions arousing special interest have been the periosteal and endosteal formation of bone, direct and indirect ossification, the factors which might have an influence on the healing of bone, and, during the last few decades, questions concerned with the transplantation of hone and osteosynthesis.Investigations have been based mainly on experimental fractures, clinical and histological studies, and radiography.Gradually, agreement about the main features of the healing of fractures has been reached, but different investigations still show considerable differences of detail.Urist and Johnson's work of 1943 contains a n excellent survey of the various stages of healing of fractures and a copious bibliography, to which reference may be made.Days after fracture 2 4 7 9 243 Number of animals HE.iLlSG OF FR.