[Metaphyseal Chondrodysplasia Type Schmid: Case Report].

Osteochondrodysplasias are a heterogeneous group of abnormalities in bone and cartilage development. Metaphyseal chondroplasia Schmid type is the most frequent within its subgroup, however it has a low incidence when compared to skeletal disorders that appear in childhood, which limits its diagnostic suspicion due to the limited knowledge about this pathology. It is caused by a variant of the COL10A1 gene, which alters endochondral ossification. It is characterized by short limbs with genu varum or valgus, in addition to increasingly shorter stature with age. This case is related to a female patient of 4 years old, who presented adequate anthropometric development until the age of one year old and exhibits currently pathological proportionate short stature with an evident varum deformity. Sequence and deletion/duplication analysis was performed by a skeletal disorders panel, n which a variant in the COL 10A1 gene is reported, which together with the phenotypic and radiological findings, confirms the diagnosis. The confusion arises from the fact of considering that all bowlegs are due to rickets or the categorization of these children as idiopathic genu varum. It is important to know the osteochondrodysplasias to be able to make an adequate diagnostic suspicion in a patient with these characteristics, which are not explained under another pathology. The importance of an early diagnosis lies in the implementation of a multidisciplinary treatment, to avoid limitations in mobility and chronic pain in the patient. In addition to the family genetic screening due to its genetic dominance, facilitating genetic counseling if the biological couple is in reproductive age.