Functional outcome of growth modulation of coronal angular deformities of knee using figure of 8 plate

Angular coronal deformities around the knee are common in pediatric orthopedic practice, surgical treatment is needed when the deformity persists or progress after correction of underlying biochemical abnormalities. Corrective osteotomy unlike in adults is not satisfactory in growing children due to potential complications, therefore growth modulation surgeries are preferred in children. Staples and screw hemiepiphysiodesis are associated with permanent damage to the physis and growth disturbances. The titanium-based figure of 8 plates were introduced to overcome growth plate injuries and growth disturbances in growth modulation surgeries.We aim to evaluate the functional results of 8 plates in growth modulation in angular knee deformities. In this study, we had 25 knees in 16 patients with coronal angular deformities, with Genu Valgum in 18 knees (6 B/L) and Genu Varum in 7 cases (3 B/L). The mean deformities were Genu valgum of 25° and Genu Varum of 15°, with altered gait on ambulation. After surgery with 8 plates, mean correction of Genu Valgum was 13° and Genu Varum was 15°. The rate of deformity correction was 2.5° in both physeal surgery, 2° in distal femur physeal surge and 1.5° in proximal tibial physeal surgery. There was no implant loosening, breakage, growth arrest, and physeal bar formation. Three patients had a superficial incisional infection which responded to the oral antibiotics. Two patients developed LLD of less than 2 cm without evidence of physeal injury or bar formation. Growth modulation with the figure of 8 plates is a reliable and reproducible method of correction of angular deformities around the knee in skeletally immature patients with good functional outcome.