Idiopathic adolescent scoliosis (IAS) is a pathologic postural adaptation in 65% of cases of scolioses. The causes of this condition are determined or suggested by a series of scientific studies and clinical experience. The results of the studies imply the correlation of IAS, the pathologic movement pattern and the pathologic postural adaptation which is governed by the central nervous system's mode of function. The pattern of pathologic postural adaptation has been confirmed by different methods and procedures: a physiological analysis of the soft tissues and of the specific functioning of organs' systems, a biomechanical analysis of the muscles and joints, an analysis of mobility and the degree of motor function of body segments as well as of the whole body and also by the clinical experience gained from surgical and treatment procedures on children with IAS. Key words: idiopathic adolescent scoliosis, postural adaptation, IAS causes Idiopatska adolescentna skolioza patoloska je posturalna adaptacija u 65% slucajeva izmecu ostalih skolioza. Uzroci nastanka utvrceni su ili se pretpostavljaju kroz niz znanstvenih istrazivanja i klinicka iskustva. Istrazivanja ukazuju na povezanost IAS s patoloskim obrascem pokretanja i patoloskom posturalnom adaptacijom koju uvjetuje nacin funkcioniranja sredisnjeg zivcanog sustava. Obrazac patoloske posturalne adaptacije potvrcen je iz vise kutova; fizioloskom analizom mekih tkiva i specificnosti funkcioniranja organskih sustava, biomehanickom analizom muskulature i zglobnih sustava, analizom pokretljivosti i stupnja motoricke funkcije segmenata tijela i cijelog tijela te klinickim iskustvom tijekom operativnih zahvata i terapijskih postupaka kod djece s IAS. Kljucne rijeci: idiopatska adolescentna skolioza, posturalna adaptacija, uzroci IAS