RT Journal A1 AMILLO, SANTIAGO A1 MORA, GONZALO A1 LÉNIZ, PATRICIO T1 Progressive Genu Valgum Secondary to a Fibrous Tether at the Distal Aspect of the Femur. A Case Report* JF The Journal of Bone & Joint Surgery JO The Journal of Bone & Joint Surgery YR 1998 FD March 1 VO 80 IS 3 SP 424 OP 7 DO UL http://dx.doi.org/ AB Bilateral angular deformity of the lower extremity in children is common, and it is often due to benign physiological conditions in which the deformity corrects with growth1,2. However, unilateral angular deformity is rare and usually involves an abnormal condition such as Blount disease, fibrous dysplasia, Ollier disease, dyschondrosteosis, neurofibromatosis, a growth disturbance resulting from a physeal injury or infection, or even a rare condition described as tibia vara caused by focal fibrocartilaginous dysplasia2. To our knowledge, only five children with unilateral angular deformity of the distal end of the femur secondary to a focal fibrous tether have been described in the literature, and only two of them had a valgus deformity1,3.