Congenital pseudarthrosis of the tibia treated with intramedullary rodding and cortical bone grafting: a follow-up study at skeletal maturity.

BACKGROUND

The problems of managing congenital pseudarthrosis of the tibia include difficulty in obtaining union, refractures, limb-length inequality, and deformities of the ankle and leg. As the problems may develop at different stages of growth, these children must be followed till skeletal maturity. This study evaluates the results of the treatment of congenital pseudarthrosis of the tibia by excision of the pseudarthrosis, transarticular intramedullary rodding, and onlay autogenous cortical bone grafting in a cohort of children followed till skeletal maturity.

METHODS

Eleven of 38 children treated with this technique for more than 20 years reached skeletal maturity. Their case records and radiographs were reviewed and each child was assessed clinically and radiographically at final follow-up (mean age, 18.4 y). The time to union and details of additional operations during the period of follow-up were noted. At final follow-up the status of union of the pseudarthrosis, deformities of the tibia and ankle, and the limb lengths were documented. The function of the ankle was assessed by applying the American Orthopaedic Foot and Ankle Society ankle-hindfoot Score.

RESULTS

Union of the pseudarthrosis was achieved in 9 of 11 children after the index operation, and in 2 cases after further surgery. At final follow-up, all 11 patients had a soundly united tibia, although persistent fibular pseudarthrosis was present in 10 patients. Ten children underwent 21 secondary operations for various indications. At final follow-up anterior or medial bowing of the tibia, ranging from 5 to 28 degrees, were noted in 7 patients and ankle valgus was present in 5 patients. The mean shortening was 2.6 cm. Only 1 patient with 8 cm shortening used a brace with a sole raise. Only 3 patients who had their transarticular rods removed had satisfactory ankle motion. The American Orthopaedic Foot and Ankle Society ankle-hindfoot scores ranged between 70 and 98. No patient experienced pain. There was no donor site morbidity.

CONCLUSION

Excision of pseudarthrosis, intramedullary rodding, and cortical bone grafting is very effective in achieving union of congenital pseudarthrosis of the tibia but a proportion of children will require additional operations to deal with refractures and other complications.

LEVEL OF EVIDENCE

Level IV.