ObjectiveTo explore the efficacy and safety of the axial load mechanical testing for removing external fixator. MethodsBetween January 2014 and August 2015, 27 patients with tibia and fibula fractures caused by trauma underwent an external fixation. Of 27 patients, 21 were male and 6 were female with the average age of 45 years (range, 19-63 years), including 7 cases of closed fracture and 20 cases of open fracture. X-ray film results showed spiral unstable fracture in 4 cases and comminuted unstable fracture in 23 cases. All patients underwent an external fixation. Bone nonunion occurred in 3 cases because of infection, and bone nonunion combined with bone defect occurred in 1 case, who received tibial osteotomy lengthening surgery. When X-ray film showed continuity high density callus formation at fracture site, axial load mechanical test was performed. If the axial load ratio of external fixator was less than 10%, the external fixator was removed. ResultsAt 21-85 weeks after external fixation (mean, 44 weeks), axial load mechanical test was performed. The results showed that the axial load ratio of external fixation was less than 10% in 26 cases, and the external fixator was removed; at 6 weeks after removal of external fixator, the patients could endure full load and return to work, without re-fracture. The axial load ratio was 14% in 1 case at 85 weeks, and the X-ray film result showed that fracture did not completely heal with angular deformity; re-fracture occurred after removing external fixator, and intramedullary fixation was used. ConclusionExternal fixator axial load mechanical testing may objectively reveal and quantitatively evaluate fracture healing, so it is safe and reliable to use for guiding the external fixator removal.
ObjectiveTo review the research progress on correction of severe foot and ankle deformities with digital hexapod external fixators. Methods The relevant research literature on digital hexapod external fixators at home and abroad in recent years was reviewed and analyzed. Taking Taylor spatial frame (TSF) as a representative, this article elaborates on the research progress of this technology in the treatment of severe foot and ankle deformities from aspects such as device principle, technical characteristics, clinical application, complication management, and controversial perspectives, aiming to provide theoretical references for clinical application. Results The treatment of severe foot and ankle deformities is a complex challenge in orthopedics, often involving multiple plane alignment abnormalities, muscle weakness, soft tissue contractures, and joint dysfunction. The digital hexapod external fixators (such as TSF), based on the principle of six degrees of freedom motion and combined with computer-assisted technology, enables precise correction of multi-dimensional deformities. Conclusion The digital hexapod external fixators provides a minimally invasive and efficient option for the treatment of severe foot and ankle deformities, and shows significant advantages in the treatment of complex post-traumatic deformities, neuromuscular deformities, diabetes Charcot arthropathy, and other diseases.
ObjectiveTo explore the effectiveness of bone transportation by ring type extenal fixator combined with locked intramedullary nail for tibial non-infectious defect. MethodsBetween June 2008 and October 2012, 22 cases of tibial large segment defect were treated. There were 15 males and 7 females, aged 24-58 years (mean, 36.8 years), including 17 cases of postoperative nonunion or malunion healing, and 5 cases of large defect. After debridement, bone defect size was 5.0-12.5 cm (mean, 8.05 cm). Bone transportation was performed by ring type external fixator combined with locked intramedullary nail, the mean indwelling duration of external fixation was 10.2 months (range, 2-26 months); the external fixation index was 1.57 months/cm (range, 0.3-3.2 months/cm); and the mean length increase was 8.05 cm (range, 5.0-12.5 cm). ResultsAll patients were followed up 19-58 months (mean, 32 months). No infection occurred after operation and all patients obtained bony union, and the union time was 4.7-19.4 months (mean, 11.9 months). Complications included refracture (1 case), skin crease (1 case), lengthening failure (1 case), foot drop (2 cases), retractions of the transport segment (1 case), delay of mineralization (1 case), which were cured after corresponding treatment. According to Hohl knee evaluation system to assess knee joint function after removal of external fixator and intramedullary nail, the results were excellent in 15 cases, good in 5 cases, and fair in 2 cases, with an excellent and good rate of 90.9%; according to Baird-Jackson ankle evaluation system to evaluate ankle joint function, the results were excellent in 10 cases, good in 3 cases, fair in 7 cases, and poor in 2 cases, with an excellent and good rate of 59.1%. ConclusionBone transportation by ring type external fixator combined with locked intramedullary nail could increase stability of extremities, allow early removal of external fixator and avoid axis shift of extremities, so it has good effect in treating tibial noninfectious defect.
The causes of development of 56 cases of bone defects from firearm injuries of extremities were analyzed, and the advantages of transfer of vascularized iliac bone graft with deep iliac circumflex vessels in 28 cases and the indications of transfer of vascularked fibular bone graft with fibular vessel in 15 cases and the exporiences in 9 cases from the methed of transter of seapula-cutaneous composite graft were summarized. It was emphatically pointed out that the half-circle typo externa fixators had its unique advantages in the treatment of the bone defects of long bones of extremities from firearm injuries. It would enentually become the method of priority for the treatment of fractures, nonunion of fractures and bone defects of extremities from firearm injuries.