We report the treatment in 17 patients of 27 angular deformities of the long bones by progressive opening-wedge osteotomy. The technique consists of percutaneous osteotomy and progressive angular correction using a modified Wagner distractor. Ten patients (20 bone segments) had adolescent bilateral idiopathic tibia vara with a mean angular deformity of 12 degrees varus (10 to 16). Seven other adolescent patients had secondary angular deformities either at the distal femur or the distal tibia. One of the femoral deformities had an associated 5.5 cm of shortening which was treated simultaneously. The patients with idiopathic tibia vara achieved a final mean angular correction of 15 degrees (mechanical axis from 12 degrees varus to 3 degrees valgus). In patients with secondary angular deformities the mean angular correction was 17 degrees. The Wagner device was removed in an average period of 12 weeks (9 to 27), and no major complications were observed. Progressive opening-wedge osteotomy is an alternative to conventional osteotomies for the treatment of angular deformities of the long bones in adolescent patients, and has the advantage of requiring less invasive surgery, allowing progressive and adjustable correction with bone lengthening if needed.