Epidemiology and treatment outcome of congenital pseudarthrosis of the tibia.

PURPOSE: Congenital pseudarthrosis of the tibia (CPT) is a rare disease. Epidemiological data are limited, and treatment of the condition is challenging. The purpose of our study was to gain epidemiological data on the incidence of CPT in Norway and to evaluate the treatment outcome of the disease.

METHODS: During the period 1987-2006 22 patients with CPT were born in Norway (11 boys, 11 girls; mean age 15 years, age range 8-24 years) and are included in this study. During the same time period 1,183,380 live-births were registered by the Norwegian Birth Register. Primary surgical treatment was the Ilizarov method in 15 patients, intramedullary nailing in three patients, and plate osteosynthesis in two patients; two patients never developed a fracture and were treated with an orthosis.

RESULTS: The incidence of CPT based on this period was 1:53,000. The rate of primary healing was 66 % for the Ilizarov group. Primary healing occurred in three patients treated with intramedullary nailing and in none of the patients treated with plate osteosynthesis. However, almost all patients required additional surgery due to refracture or deformity correction. Currently, all 12 skeletally mature patients are considered to be healed, whereas two of the skeletally immature patients are still under treatment.

CONCLUSION: The incidence of CPT in Norway seems to be notably higher than that based on epidemiological data from other studies. Primary healing rates are satisfactory when treated either with an Ilizarov device or intramedullary nailing. Refractures must be avoided, and alignment of the leg must be maintained. Healing is usually achieved before skeletal maturity. However, residual deformities are common.