Perthes’ Disease: Is the Epiphysial Infarction Complete? a Study of the Morphology in Two Cases

276 THE JOURNAL OF BONE AND JOINT SURGERY Despite an increasing interest in the morbid anatomy of Perthes’ disease, reports on human cases remain few and their conclusions indefinite. The classification of the radiological features and natural history by Catterall (1971) led to the conclusion that the prognosis was proportional to the degree of epiphysial involvement. This suggests that the size of the infarct is variable from case to case, and hence that the whole epiphysis is not necessarily always involved. This paper presents two cases in which detailed histological analysis has been made. MATERIAL AND METHODS In two cases of Perthes’ disease a study was made of the radiographs and the affected hips obtained at necropsy. A coronal slab was cut from the centre of each femoral head, the anterior and posterior segments were cut into five-millimetre slabs at right angles to this plane, and fine-detail radiographs were made of all these blocks.