CHRONIC RECURRENT MULTIFOCAL OSTEOMYELITI S (CRMO)

Chronic recurrent multifocal osteomyelitis (CRMO) is an unusual clinic al entity. More than 200 cases are described in the literature and it is presented here with special reference to its radiological aspects. It is an acquired disease of the skeleton which occurs predominantly d uring childhood and adolescence. About ten per cent of cases begin in early or, rarely, in later adult life. This variant is described here for the first time and is discussed as ''adult CRMO''. The underlying pathology is a bland, predominantly lympho-plasma cellular osteomyelit is which is self-limiting and leads to bone sclerosis (Garre). It prob ably involves an abnormal immune process which follows an infection bu t remains clinically latent and remains aseptic and sterile. In a quar ter of cases there is an association with pustulosis palmo-plantaris a nd its relationship with psoriatic arthropathy is discussed. The clini cal, histopathological and imaging features (radiological and particul arly MRT) and the bone changes are described. This provides a spectrum of symptoms; the radiological differential diagnosis and the relation ship with hyperostotic spondyloarthroses during adult life are discuss ed. The relationship between CRMO, the SAPHO syndrome and acquired hyp erostosis syndrome are analysed.