ESSENTIAL BONE-CYSTS IN CHILDREN - CONTRI BUTION OF ROUTINE CYSTOGRAPHY - A SERIES OF 42 CYSTS

Introduction The treatment of childrens essential bone cysts, is contr oversial. Intra focal injection of a corticord, the Methylprednisolone , described by Scaglietti in 1974, gived in most of the case serials, a rate of healing of more than 30 per cent. Material and methods The c ase serial we present includs 42 essential bone cysts treated beetwen 1975 and 1992 in the orthopaedic department of Necker Enfants Malades hospital. These children have been reviewed with a mean follow up of 4 years. A healing rate over 35 per cent has been noticed. However, som e failures stayed completely an understanding even if nothing at the b eginning let supose a slower evolution. Results Attempting to explain those phenomenes, the autors realised in 70 per cent cases, an opaque cystography, before the Methylprednisolone injection. This simple radi ological technique permitted to reveal abnormal aspect in 75 per cent cases. Most of the time, it shows massive-veinous licks in an abnormal veinous system or one or plurial separations of the cystic area. This type of picture could perfectly explain the defect of the corticoids action by a lick of the solution or by a partial unefficacity of the s olution because of the separation in the cyst area. The hypothetic ide a has been completed by the calcul of the duration of the evolution. E ffectively, the cysts showing an abnormal cystography had a longer hea ling delay compared to the cyst whose cystography was normal. Conclusi on The opaque cystography is for us a necessary element in the treatme nt of essential bones cysts, once the diagnostic is certain and the in dication of intra focal corticoid injection has been retained. The rad iographic study of the cyst area permits to precise the treatment; for example multiplying the injections in the areas of the cysts when the re is separations and overseing the evolution.