LCP Plates in Congenital Pseudarthrosis of the Tibia Treated by Vascularized Fibular Transfer: A New Method of Bone Fixation

Congenital pseudarthrosis is a rare condition that can present in several forms. The most common is the displasic fractured tibia presenting anterior and lateral angulations. In general, there is an association with neurofibromatosis. Treatment consists of resection of the diseased bone, interposition of a vascularized bone graft, and alignment and correction of rotation and length of the lower leg.

The surgical technique is well–defined, since bone healing is best achieved by transplantation of a vascularized fibular graft. Also, tibialization is rapid in the early ages. If a stable fixation is easily attained in the peri–operative stage, it remains dificult to maintain during the months that follow surgery, despite the use of KAFO. In fact, the patients have been small children, economically poor, and with very restricted social conditions. Taking care of this pediatric population is quite difficult; often they are left alone and start walking by themselves without surveillance.

The series of congenital pseudarthrosis treated with vascularized fibular grafts has reached 22 patients in the last 20 years. The ages of patients ranged from 11 months to 9 years, with a mean of 4 years 9 months. Most of them (95.45%) were treated with vascularized fibular grafts. Bone fixation was performed by external fixation in 3 cases, intramedulary nail in 12 cases, oblique K wires in 3 cases, and LCP plates in 4 cases. Failure of the transplant occurred in 1 patient (4.55%). The incidence of non union was 33% with external fixation, 58.33% with intramedullary nail, 66.5% with oblique K wire, and 25% with LCP plate fixation. Final consolidation was obtained in 90.9% of cases.

Although there is a controversy about the influence of bone fixation method over the final results, the authors observed that the new LCP plate produces excelent results in the osteopenic tibia lower third, when compared to other methods. The advantage of screwing across the recepient bone and fixing directly to the plate as an internal fixator allows early charging of the lower limb, dynamization of both ends, and rapid consolidation and tibialization of the transplant.