1. Details of clinical, radiological, biochemical and histological investigations of a case of metaphysial dysostosis are presented. 2. The patient was a boy of seven years, and showed widespread lesions (involving long bones of limbs, small bones of hands and feet, pelvis, clavicles, and ribs) characterised by retardation of growth and ossification with masses of partly calcified tissue in the metaphyses. 3. No radiological, clinical or histological evidence of renal osteodystrophy was found in the case described. 4. Metaphysial dysostosis is discussed in relation to other chondrodystrophies.
Two cases of benign osteoblastic tumours of the spine, occurring in young patients, and presenting as expanding osteolytic lesions with some central calcification and ossification, are described. It is suggested that they represent a condition allied to, but usefully separated from, osteoid osteoma of bone. The name osteogenic fibroma of bone, proposed by Lichtenstein for this type of case, is accepted.
1 . The repair of a simple crush injury was studied in rats, in both normally innervated and completely denervated muscle. In each case the histological findings at periods from two hours to thirty-two weeks are described. 2. The denervated muscle showed active and effective repair. 3. A comparison with the findings in normally innervated muscle establishes that the cellular processes of repair do not depend on connections with the central nervous system.
The effect of cortisone on the repair of simple muscle injury was studied in rabbits. The histological findings in the crushed muscle are described for a period up to twenty-one days after injury. Cortisone defers the onset of muscle regeneration, and retards its progress, but it does not change the course of the repair process or alter its eventual outcome under the conditions of the experiment. This apparent refractoriness of repair of muscle, as compared with that of other connective tissues, is discussed.
Amputation or post-mortem specimens from eight cases of joint tuberculosis, with immobilisation changes in bone, have been studied by fine-detail slab radiographs and subsequent histological examination. The findings in three of these cases are presented in detail. The immobilisation changes take the form of a true osteoporosis, which is strikingly focal in nature. In the adult the sites of most marked involvement include the subcortical bone adjacent to articular surfaces and the bone in the neighbourhood of the obliterated epiphysial plates. Areas of permanent change in bone structure may result, although commencing "repair" is seen in the form of newly developed bone trabeculae in the osteoporotic areas. In one case, where immobilisation occurred at an early age, changes in the growing epiphysial plates were produced in addition to osteoporosis. This is correlated with the known susceptibility of growing epiphysial cartilage to a wide variety of damaging agents. Radiologically, it is important to discriminate between these immobilisation changes and the bone destruction which might be produced by extension of the tuberculous lesion itself.
A case is described in which a clinical diagnosis of "metaphysial dysostosis" was made, but in which histological examination of involved bones showed the changes of rickets, presumably renal, with secondary hyperparathyroidism.
