Treatment of infected nonunion of the distal juxta-articular tibia is a challenge due to a short distal fragment, deformity, thin soft-tissue envelope, and active infection. There is still no consensus on the approach that is able to maximally salvage the limb and ankle function.

Infected juxta-articular nonunion of the distal tibia was managed with two Ilizarov techniques, monofocal compression (MC) used in 12 patients and bifocal compression-distraction (BCD) in 6 patients. The choice of the technique depended on the size of the postresection defect, ≥3 cm or ≤3 cm, respectively. The tactics of functional approach were careful debridement, insertion of wires in the distal fragment so that they do not penetrate the ankle joint, stable fixation, and temporary bridging of the ankle and forefoot. MSCT was used along with regular radiography to assess the union and regeneration. Ankle functions were evaluated with AOFAS ankle-hindfoot score system.

Bone consolidation, infection arrest and ankle function improvement were achieved in all patients. External fixation continued 221.7 ± 15.1 days for MC and 235 ± 25.8 days for BCD. Complications were wound divergence, wire-tract infection, premature consolidation of the fibula, and hypoplastic regeneration in one case. The mean functional AOFAS score after treatment was 90.7 ± 2.5 points in MC and 89.7 ± 1.3 in BCD patients. Residual limb discrepancy after MC ranged 0-4 cm. Bone shortening was compensated in BCD patients.

Limb-salvage and functional approach to the treatment of infected nonunion of the juxta-articular distal tibia with the Ilizarov techniques achieves good outcomes. It provides bone infection arrest, consolidation, defect compensation and significantly improves the ankle joint function.

Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in long bone defect and nonunion management along with free vascularized grafting and induced membrane technique. However, the shortcomings and problems of these methods still remain the issues which restrict their overall use.

To study the recent available literature on the role of Ilizarov non-free bone plasty in long bone defect and nonunion management, its problems and the solutions to these problems in order to achieve better treatment outcomes.

Three databases (PubMed, Scopus, and Web of Science) were searched for literature sources on distraction osteogenesis, free vascularized grafting and induced membrane technique used in long bone defect and nonunion treatment within a five-year period (2015-2019). Full-text clinical articles in the English language were selected for analysis only if they contained treatment results, complications and described large patient samples (not less than ten cases for congenital, post-tumor resection cases or rare conditions, and more than 20 cases for the rest). Case reports were excluded.

Fifty full-text articles and reviews on distraction osteogenesis were chosen. Thirty-five clinical studies containing large series of patients treated with this method and problems with its outcome were analyzed. It was found that distraction osteogenesis techniques provide treatment for segmental bone defects and nonunion of the lower extremity in many clinical situations, especially in complex problems. The Ilizarov techniques treat the triad of problems simultaneously (bone loss, soft-tissue loss and infection). Management of tibial defects mostly utilizes the Ilizarov circular fixator. Monolateral fixators are preferable in the femur. The use of a ring fixator is recommended in patients with an infected tibial bone gap of more than 6 cm. High rates of successful treatment were reported by the authors that ranged from 77% to 100% and depended on the pathology and the type of Ilizarov technique used. Hybrid fixation and autogenous grafting are the most applicable solutions to avoid after-frame regenerate fracture or deformity and docking site nonunion.

The role of Ilizarov non-free bone plasty has not lost its significance in the treatment of segmental bone defects despite the shortcomings and treatment problems encountered.

Hierarchical structure has exhibited an important influence in the fields of supercapacitors, catalytic applications, and tissue engineering. The hot dog, a popular food, is composed of bread and sausage with special structures. In this study, inspired by the structure of a hot dog, the strategy of combining direct ink writing 3D printing with bidirectional freezing is devised to prepare hot dog-like scaffolds with hierarchical structure. The scaffolds are composed of hollow bioceramic tubes (mimicking the "bread" in hot dogs, pore size: ≈1 mm) embedded by bioceramic rods (mimicking the "sausage" in hot dogs, diameter: ≈500 µm) and the sausage-like bioceramic rods possess uniformly aligned lamellar micropores (lamellar pore size: ≈30 µm). By mimicking the functions of hierarchical structure of bone tissues for transporting and storing nutrients, the prepared hot dog-like scaffolds show excellent properties for loading and releasing drugs and proteins as well as for improving the delivery and differentiation of tissue cells. The in vivo study further demonstrates that both the hierarchical structure itself and the controlled drug delivery in hot dog-like scaffolds significantly contribute to the improved bone-forming bioactivity. This study suggests that the prepared hot dog-like scaffolds are a promising biomaterial for drug delivery, tissue engineering, and regenerative medicine.