Abstract
Blount's disease in pairs of twins has been reported rarely. The authors report identical twin girls, each affected in both legs. The girls were delivered normally at birth and were generally healthy. They had normal parents and elder brothers.
The authors first examined the girls at the age of 2 years. Both girls had marked bilateral gene varum. In one twin, the deformities appeared to be progressing in severity, therefore correction of O-leg deformity, avoiding irreversible change of proximal tibia epiphysis, and corrective osteotomy was done by lateral open wedge at the age of 2 years and 6 months. The authors latest follow-up examination was at the age of 3 years, 6 months after operation, the deformities have almost recovered, both legs showed good alignment.
X-ray films of the second girl showed Metaphyseal-Diaphyseal Angle (MDA) has recoverd, but proximal tibia epiphysis was classified as represented langenskiöld stage II. The patient's condition continues to be followed closely.
Blount's disease is suggested to be under genetic control, and there are a few reports about familial occurrence. In those reports the mode of inheritance was thought to be an autosomal dominant, recessive, or multifocal disorder, but its genetic association remains unclear as in our cases.
