Congenital Pseudoarthrosis of the Tibia (CPT) is a rare condition with a reputation for recurrent fractures and failure to achieve union. A large variety of surgical procedures have been attempted for the treatment of fractured cases of CPT with an average rate of union without refracture of only 50%. Intentional cross-union between the tibia and fibula has been reported to improve these results to 100% union with no refractures. This is a retrospective study of 39 cases of CPT in 36 patients treated by the Paley cross-union protocol with internal fixation, bone grafting, zoledronic acid infusion and bone morphogenic protein 2 (BMP2) insertion. All 39 cases of CPT united at the tibia and developed a cross-union to the fibula. Two patients had a persistent fibular pseudarthrosis, one that was later treated at the time of planned rod exchange and one that has remained asymptomatic. There were few postoperative complications. There were no refractures during the up to 7-year follow-up period. The most common problem was the Fassier-Duval (FD) rod pulling through the proximal or distal physis into the metaphysis (66.7%). This did not negatively affect the results and was remedied at the time of the planned rod exchange. The Paley Cross-Union Protocol is very technically demanding, but the results have radically changed the prognosis of this once sinister disease.
Keywords: BMP; NF1; anterolateral bowing; bisphosphonate; bone graft; congenital pseudarthrosis of the fibula; congenital pseudarthrosis of the tibia (CPT); cross-union; hamartoma; neurofibromatosis 1; zoledronic acid.