1. Four cases of polyostotic fibrous dysplasia are presented. 2. All are males, all show cutaneous pigmentation, and in two there has been precocious puberty. 3. The literature has been reviewed, and present conceptions of the pathology and etiology of the disease have been discussed. 4. The dysplasia if often confused with parathyroid osteodystrophy and sometimes the parathyroid glands are needlessly explored. This confusion should not arise if it is remembered that no general skeletal decalcification, and no constant changes in the blood calcium or phosphorus, occur in polyostotic fibrous dysplasia. The radiographic appearances of healing parathyroid osteodystrophy are, however, indistinguishable. 5. No effective therapy has been discovered for this disease. Pathological fractures and deformities may require treatment.
Posterior dislocation of the shoulder is an unusual injury and there is often much delay before the diagnosis is made. Nevertheless, if the condition is borne in mind when examining the patient and studying the X-ray films the diagnosis should not be missed. A single antero-posterior radiograph of the shoulder joint is inadequate. For the radiologist a pair of stereoscopic films is desirable; but for routine emergency work in hospital other projections are necessary. A vertical view should be taken, either with the limb abducted and the tube in the axilla, or with the tube above the shoulder and a curved cassette in the axilla. When this is impossible a profile or posterior oblique view of the scapula may be substituted.
