Aims. The treatment of tibial aplasia is controversial. Amputation represents the gold standard with good functional results, but is frequently refused by the families. In these patients, treatment with reconstructive limb salvage can be considered. Due to the complexity of the deformity, this remains challenging and should be staged. The present study evaluated the role of femoro-pedal distraction using a circular external fixator in reconstructive treatment of tibial aplasia. The purpose of femoro-pedal distraction is to realign the limb and achieve soft tissue lengthening to allow subsequent reconstructive surgery. Methods. This was a retrospective study involving ten patients (12 limbs) with tibial aplasia, who underwent staged reconstruction. During the first operation a circular hexapod external fixator was applied and femoro-pedal distraction was undertaken over several months. Subsequent surgery included reconstruction of the knee joint and alignment of the foot. Results. The mean follow-up was 7.1 years (2 to 10). The mean age of the patients at the time of the application of the fixator was 2.3 years (1.1 to 5.0). The mean time under distraction was 139.7 days (81.0 to 177.0). A mean fibular distalization of 38.7 mm (14.0 to 67.0) was achieved. Pin infections occurred in four limbs (33.3%) and osteitis in one. A femoral fracture occurred in one patient. Premature removal of the frame was not required in any patient. Sufficient realignment of the leg as well as soft tissue lengthening was achieved in all patients, allowing subsequent reconstruction. All patients were able to mobilize fully weight bearing after reconstruction. Functional outcome was limited in all limbs, and five patients (50.0%) required additional reconstructive operations. Conclusion. Regarding the functional results in the treatment of tibial aplasia, amputation remains superior to limb salvage. The latter procedure should only be performed in patients whose parents refuse amputation. Femoro-pedal distraction efficiently prepares the limb by realigning the leg and soft tissue lengthening. Minor complications are frequent, but usually do not hinder the continuation of distraction. Even though a fully weight-bearing limb is achieved, the functional outcome of reconstructive treatment remains limited. Recurrent deformities frequently occur and may require further operations. Cite this article: Bone Joint J 2020;102-B(9):1248–1255

Untill recently, major reduction defects of the tibia were treated by amputation and prosthetic fitting. However, Wada et al (1) and Weber (2) recently reported impressive results of limb reconstruction in children with tibial aplasia. If an attempt is being made to reconstruct the leg and foot, a clear understanding of the nature of anomalies is necessary. A retrospective study of case records and radiographs of children with congenital anomalies of the tibia seen at our centre was undertaken to determine the patterns of associated anomalies in the leg and foot. In addition, five amputated specimens of the leg and foot from children with complete tibial aplasia were dissected. A wide spectrum of congenital anomalies of the tibia was seen and this included complete aplasia, partial aplasia, hypoplasia, dyplastic trapezoidal tibia and congenital bowing. Complete and partial aplasia was seen either with or without duplication of the formed skeletal elements. The patterns of duplication that were seen included fibular dimelia, pre-axial mirror polydactyly, duplication of the calcaneum, cuboid and lateral cuneiforms. Trapezoidal dysplastic tibia was associated with duplication of the talus and pre-axial mirror polydactyly. Dissection of the amputated specimens of complete tibial aplasia revealed aplasia of some muscles, aberratant tendinous structures, abnormal insertion of muscles and absence of the plantar arterial arch. An understanding the nature of these associated anomalies in children with tibial aplasia and dyplasia will help the surgeon to decide the strategies for reconstruction of the limb if that is the desired option. At the other end of the spectrum of congenital anomalies of the tibia is posteromedial bowing which was considered an innocuous condition that required little or no treatment. A review of 20 cases of posteromedial bowing demonstrated that there are number of problems related to the leg, ankle and foot that may require surgical intervention

Tibial hemimelia is a rare congenital anomaly, occurring approximately in 1 per 1million live birth and consisting of aplastic/hypoplastic tibia with relatively intact fibula. The widely used classification was proposed by Jones and based on radiological description: type I: tibia absent, type II distal tibia not seen, type III proximal tibia not seen, type IV tibio-fibular diastases. This congenital deformity can be unilateral or bilateral and isolated, or unilateral or bilateral and associated with other malformation witch raise its genetic cause. We are reporting the cases of two monozigotic twins reflecting the “intragenotic” expression variability of the syndrome of tibial aplasia and ectrodactyly. The two monozigotic female twins are born after an unremarkable first pregnancy and delivery. Family history was positive for malformations.(syndactily, split hand, phocomelia(elbow) and hip dyspasia). Twin 1: Left leg: tibial aplasia type Ia, short femur, absent patella. Right leg: tibial aplasia type IV, clubfoot, hypoplasia of the internal ray. Left hand: split hand. Twin 2: Left leg: nornal. Right leg: tibial aplasia type II, clubfoot. Left hand: split hand. Most of the cases are unilateral and sporadic. 4 autosomal dominant tibial hemimelia syndromes are described. tibial hemimelia-foot polydactyly-triphangeal thumbs syndrome,. tibial hemimelia diplopodia syndrome,. tibial hemimelia-split-hand foot syndrome,. tibial hemimelia micromelia-oigonobrachycephaly syndrome. This is the first documennted case of monozigotic twins affected by the Tibial hemimelia-split-hand foot syndrome. Their clinical presentation demonstrates that the phenotypic manifestations are highly variable

1. A family is reported in which tibial aplasia with polydactyly of hands and feet and absent thumbs occurred in a father and daughter. 2. The evidence suggests the existence of an autosomal dominant mutant gene that causes absent thumbs and manual polydactyly, with or without varying degrees of tibial hypoplasia and pedal polydactyly