Estudio de la osificación del segundo radio del pie en la edad pediátrica

Resumen

Analyzing prospectively 231 patients from a Spanish modern pediatric population a total of 1001 radiographic feet films are presented. Using an informatic visual and measure tool, the bones of the second ray of the foot are examined, in order to determine the sequence of ossification, the sequence of partial and final closure of the physis of this ray, the characteristics of signs of avascular necrosis in the epiphysis, the existence of a proximal secondary ossification center of the second metatarsal and its characteristics, and finally create a model of estimation of bone age using the measurements of the intermediate cuneiform, the epiphysis (proximal and distal) of the second metatarsal, and proximal epiphysis of the phalanges of the second toe. By means of statistic analysis, these data are analyzed to see the influence in those items of anthropologic variations such as sex, laterality, digital and metatarsal formula, and orthopaedic pathology. It is proved that digital and metatarsal formula are not stable in time, and can vary during growth. The sequence of ossification, and closure of the physis of the intermediate cuneiform, epiphysis of the second metatarsal and epiphysis of the phalanges of the second toe are determined, and their modifications with anthropologic factors and orthopaedic pathology are noted. The prevalence and characteristics of radiographic signs that suggest avascular necrosis on those same epiphysis are stated, as well as the variations occurred with anthropologic factors and orthopaedic pathology. The existence of a proximal epiphysis of the second metatarsal is proved, more frequently in girls. It has a prevalence of 3% of our population, appearing at the age of 2,3 years old, and closing completely at the age of 9,3 years old. This closure is delayed in flat feet, greek digital formula and index minus. This center is associated with flat feet. A morphologic classification is drawn. This epiphysis seems to behave as a pseudoepiphysis, with no potential influence in growth. The presence of anepiphysis ossification of the second phalange of the second toe is described, presenting in a total of 4,3% of the patients, more frequently in girls and associated with flat feet and egyptian digital formula. This phalanges grow less than normal epiphyseal phalanges. Finally, a morphometric study of these growth centres is presented, and lineal and exponential models are created in order to determine bone age.