Application of 3-in-1 osteosynthesis in combined surgical technique for congenital pseudarthrosis of the tibia in children

Abstract

Objective To explore the indications, operative technique and outcomes of combined surgical technique and 3 in 1 osteosynthesis for congenital pseudarthrosis of the tibia (CPT). Methods A retrospective study was performed on 17 children of Crawford type IV CPT with fibular intact undergoing combined surgical technique and 3 in 1 osteosynthesis from March 2014 to August 2015.There were 12 boys and 5 girls with an average operative age of 3 (1.1-7.7) years.Ten patients were aged under 3 years.Fifteen patients had no previous surgery, but two patients were unsuccessfully operated at another hospital.Among them, there were proximal tibia dysplasia (n=4) and neurofibromatosis type I (n=1). Combined surgical technique and 3 in 1 osteosynthesis included proximal fibular osteotomy, excision of pseudarthrosis, intramedullary rod insertion, installation of ilizarov's fixator, tibio-fibular cross union and wrapping autogenic iliac bone graft.Two patients had proximal tibial lengthening.The incidence of refracture, ankle valgus, tibial valgus and limb length discrepancy (LLD) were tracked during an average follow-up period of 19.5 (9-26) months. Results Two patients underwent tibia lengthening simultaneously.The average operative duration was 4.1(3.3-4.2) hours.All patients achieved primary union.The average primary union time was 4.9 (4.1-7.8) months.And 13 (76%) cases showed LLD with an average limb length of 1.2 (0.5-2.0) cm while 6 (35%) cases exhibited tibial valgus with an average tibial valgus deformity of 7.8° (5° -16° ). Two cases had ankle valgus.One case had an ankle valgus deformity of 12° while another case 17°.The cross sectional area of bone graft was enlarged to 1.74 (1.14-2.60) times of tibia shaft.No refracture occurred during the follow-ups.Five cases had movement of ankle joint restored with an average dorsiflexion of 22°(20°-30°)and an average plantar flexion of 41°(40°-50°). And function of ankle joint was normal. Conclusions Combined surgical technique and 3 in 1 osteosynthesis are indicated primarily for bony union with a large cross-sectional area.The rate of early healing is high.It can provide satisfactory short-term outcomes for CPT. Key words: Child; Congenital Pseudarthrosis of Tibia; Treatment outcome