Prognostic evaluation of Legg-Calvé-Perthes disease by MRI. Part I: the role of physeal involvement.

Twenty-eight unselected hips affected by Legg-Calvé-Perthes disease (LCPD) in 24 patients from 1987 to 1994 had magnetic resonance imaging (MRI) performed. The patients were retrospectively reviewed at a mean follow-up of 5.4 years. An interobserver blind analysis was made to establish the reliability of four MRI parameters: extent of epiphyseal necrosis (EXT), lateral extrusion of the femoral head (LAT), physeal involvement (PHY), and metaphyseal changes (MET). The interobserver analysis resulted in a good reliability for all MRI parameters (concordance, >80%; K index, >0.45). A statistical correlation study (Spearman test) was then done between each MRI parameter and the condition of the hips at follow-up evaluated by Stulberg class and a personal scored system (total score) of clinical-radiographic condition. All MRI parameters appeared well correlated to the Stulberg class and to the total score (S > 0.66; p < 0.05). PHY resulted the strongest correlated parameter (S = 0.84 for Stulberg class; S = 0.91 for total score). Finally our statistical correlation study demonstrates physis involvement to have a high predictive value in LCPD; therefore it can be assumed as the main risk factor in formulating prognosis.

Growth disturbances following fractures of the femur and tibia in children.

Growth disturbances can occur following fractures of the femur or tibia in children. They can produce lengthening, shortening, axial and rotational deformities. The number of variable factors involved is such that valid statistical analysis demands a very large series of well documented cases followed up until growth ceases or stabilisation is established. We hope to inaugurate such a survey in collaboration with other large centers. In the present limited survey of 174 the only statistically valid conclusions were that age and type of treatment are relevant factors in producing lengthening. In the other factors investigated the survey was not large enough to provide valid answers. It has been established that after metaphyseal or diaphyseal fractures in children disturbances of growth may occur resulting in accelerated growth, retarded growth, axial deformities and rotational deformities. The literature, although extensive, leaves many questions unanswered while on other matters, such as the role of certain factors in the pathogenesis of these disturbances, there is often conflicting data. In a brief review of the literature we decided to simplify our research by confining our observations to data relating only to single diaphyseal fractures.