Functional outcome and complications after treatment of comminuted tibial fractures or deformities using Ilizarov bone transport: a single-center study at 15- to 30-year follow-up

Analysis of risk factors, pathogenic bacteria characteristics, and drug resistance of postoperative surgical site infection in adults with limb fractures

PURPOSE

We carried out the study aiming to explore and analyze the risk factors, the distribution of pathogenic bacteria, and their antibiotic-resistance characteristics influencing the occurrence of surgical site infection (SSI), to provide valuable assistance for reducing the incidence of SSI after traumatic fracture surgery.

METHODS

A retrospective case-control study enrolling 3978 participants from January 2015 to December 2019 receiving surgical treatment for traumatic fractures was conducted at Tangdu Hospital of Air Force Medical University. Baseline data, demographic characteristics, lifestyles, variables related to surgical treatment, and pathogen culture were harvested and analyzed. Univariate analyses and multivariate logistic regression analyses were used to reveal the independent risk factors of SSI. A bacterial distribution histogram and drug-sensitive heat map were drawn to describe the pathogenic characteristics.

RESULTS

Included 3978 patients 138 of them developed SSI with an incidence rate of 3.47% postoperatively. By logistic regression analysis, we found that variables such as gender (males) (odds ratio (OR) = 2.012, 95% confidence interval (CI): 1.235 - 3.278, p = 0.005), diabetes mellitus (OR = 5.848, 95% CI: 3.513 - 9.736, p < 0.001), hypoproteinemia (OR = 3.400, 95% CI: 1.280 - 9.031, p = 0.014), underlying disease (OR = 5.398, 95% CI: 2.343 - 12.438, p < 0.001), hormonotherapy (OR = 11.718, 95% CI: 6.269 - 21.903, p < 0.001), open fracture (OR = 29.377, 95% CI: 9.944 - 86.784, p < 0.001), and intraoperative transfusion (OR = 2.664, 95% CI: 1.572 - 4.515, p < 0.001) were independent risk factors for SSI, while, aged over 59 years (OR = 0.132, 95% CI: 0.059 - 0.296, p < 0.001), prophylactic antibiotics use (OR = 0.082, 95% CI: 0.042 - 0.164, p < 0.001) and vacuum sealing drainage use (OR = 0.036, 95% CI: 0.010 - 0.129, p < 0.001) were protective factors. Pathogens results showed that 301 strains of 38 species of bacteria were harvested, among which 178 (59.1%) strains were Gram-positive bacteria, and 123 (40.9%) strains were Gram-negative bacteria. Staphylococcus aureus (108, 60.7%) and Enterobacter cloacae (38, 30.9%) accounted for the largest proportion. The susceptibility of Gram-positive bacteria to Vancomycin and Linezolid was almost 100%. The susceptibility of Gram-negative bacteria to Imipenem, Amikacin, and Meropenem exceeded 73%.

CONCLUSION

Orthopedic surgeons need to develop appropriate surgical plans based on the risk factors and protective factors associated with postoperative SSI to reduce its occurrence. Meanwhile, it is recommended to strengthen blood glucose control in the early stage of admission and for surgeons to be cautious and scientific when choosing antibiotic therapy in clinical practice.

Trifocal versus Pentafocal bone transport in segmental tibial defects: a matched comparative analysis for posttraumatic osteomyelitis treatment

PURPOSE

The objective of this study was to evaluate and compare the effectiveness and clinical results of trifocal bone transport (TBT) and pentafocal bone transport (PBT) in treating distal tibial defects > 6 cm resulting from posttraumatic osteomyelitis, highlighting the potential advantages and challenges of each method.

METHODS

A retrospective assessment was conducted on an overall population of 46 eligible patients with distal tibial defects > 6 cm who received treatment between January 2015 and January 2019. Propensity score analysis was used to pair 10 patients who received TBT with 10 patients who received PBT. The outcomes assessed included demographic information, external fixation time (EFT), external fixation index (EFI), bone and functional outcomes assessed using the Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system, and postoperative complications evaluated using the Paley classification.

RESULTS

The demographic and baseline data of the two groups were comparable. Following radical debridement, the average tibial defect was 7.02 ± 0.68 cm. The mean EFT was significantly shorter in the PBT group (130.9 ± 16.0 days) compared to the TBT group (297.3 ± 14.3 days). Similarly, the EFI was lower in the PBT group (20.67 ± 2.75 days/cm) than in the TBT group (35.86 ± 3.69 days/cm). Both groups exhibited satisfactory postoperative bone and functional results. Pin site infection was the most common complication and the rates were significantly different between the groups, with the PBT group demonstrating a higher incidence.

CONCLUSION

Both TBT and PBT effectively treat posttraumatic tibial defects greater than 6 cm, with PBT offering more efficient bone regeneration. However, PBT is associated with a higher rate of pin site infections, highlighting the importance of careful management in these complex procedures and emphasizing the need for expert surgical execution and tailored treatment approaches in orthopedic reconstructive surgery.

The Use of the Ilizarov Fixator for the Treatment of Open and Closed Tibial Shaft and Distal Tibial Fractures in Patients with Complex Cases

INTRODUCTION

Open and closed fractures of the tibial shaft or distal tibia can be challenging for surgeons to treat if the fractures are accompanied by aggravating conditions, such as various accompanying diseases, pronounced soft tissue injuries, osteomyelitis, and/or noncompliance. The aim of this retrospective study was to present our approach and results with the Ilizarov fixator as a treatment option for such individually complex cases.

MATERIALS AND METHODS

Between 2005 and 2018, 20 patients were treated with the Ilizarov fixator for fractures of the tibial shaft/distal tibia. The indication for this was a 2nd- to 3rd-degree open fracture in 10 patients, a 1st-degree open fracture in one patient, and closed fractures in 9 patients. Aggravating conditions included soft tissue injuries, osteomyelitis, leg deformities, multiple traumas, smoking, alcohol/drug abuse, and obesity (BMI > 60). In addition to demographic data, the time of fixator treatment, complications, and the endpoint of consolidation were evaluated retrospectively.

RESULTS

The mean time of fixator treatment was 29 (range 15-65) weeks. Complete fracture consolidation was achieved in 13 patients (65%) with the Ilizarov fixator. The mean follow-up period after fixator removal was 36 (range 2-186) months in 14 patients. Five patients with complete consolidation were lost to further follow-up. One patient was amputated. In six patients without union, internal osteosynthesis was carried out.

CONCLUSION

The use of the Ilizarov fixator is a treatment option for individual high-risk patients with complicating courses but should be seen as a salvage procedure due to the high complication rate and long treatment process.

External Fixation as a Primary and Definitive Treatment for Complex Tibial Diaphyseal Fractures: An Underutilized and Efficacious Approach

Background

External fixation is one of the most often utilized treatment options for complicated tibial diaphyseal fractures (TDF). The purpose of this study was to assess the efficacy of unilateral external fixators as primary and definitive therapy for complex TDF in a resource-limited setting.

Materials and Methods

A retrospective study between June 2016 and March 2021 included 110 subjects with TDF who were treated with an external fixator as definitive fixation in hospitals affiliated with Ibb University. The patient's demographic characteristics, complications, and outcomes were gathered and analyzed. Factors associated with pin site infection were also investigated.

Results

The mean age was 42.1 ± 10.1 years, with 92.7% being male. Rural residents accounted for 22.7%. Smoking and diabetes mellitus were present in 27.3% and 30.0%, respectively. General complications occurred in 12.0%, with pulmonary embolism being the most common at 4.5%. Orthopedic complications included pin-track infections in 27.3% (30) and osteomyelitis in 1.8% (2). Pin site infections required medical treatment in 21 cases and external fixator changes in five. Two cases each needed several debridements for osteomyelitis and soft tissue. Full union occurred in 79.1% (87) over 23.1 ± 3.2 weeks and final alignment in 97.3% (107) over 34.8 ± 4.8 weeks. Malunions occurred in 1.8% (2), and one case had hypertrophic nonunion. Factors like rural residency, smoking, diabetes, open fractures, worst fracture grade (Gustilo and Anderson type C), and general complications occurrence significantly correlated with pin site infection (all p-values < 0.05).

Conclusion

A unilateral external fixator as a primary and definitive treatment is a viable, simple, and effective option for TDF with a high success rate even in a resource-limited setting. In this study, residents in rural areas, smoking, diabetes, open fracture, worst fracture grade, and general complication occurrence were associated with pin site infection occurrence.

Advances in the Application of Bone Transport Techniques in the Treatment of Bone Nonunion and Bone Defects

Bone nonunion and bone defects frequently occur following high-energy open injuries or debridement surgeries, presenting complex challenges to treatment and significantly affecting patients' quality of life. At present, there are three primary treatment options available for addressing bone nonunion and bone defects: vascularized bone grafts, the Masquelet technique, and the Ilizarov technique. The Ilizarov technique, also known as distraction osteogenesis, is widely favored by orthopedic surgeons because of several advantages, including minimal soft tissue requirements, low infection risk, and short consolidation time. However, in recent years, the application of the Masquelet technique has resulted in novel treatment methods for managing post-traumatic bone infections when bone defects are present. Although these new techniques do not constitute a panacea, they continue to be the most commonly employed options for treating complex large bone nonunion and bone defects. This review evaluates the currently available research on the Ilizarov and Masquelet bone transport techniques applied at various anatomical sites. Additionally, it explores treatment durations and associated complications to establish a theoretical foundation that can guide clinical treatment decisions and surgical procedures for the management of bone nonunion and bone defects.

Ilizarov method and its combined methods in the treatment of long bone defects of the lower extremity: systematic review and meta-analysis

BACKGROUND

Ilizarov method has become one of primary methods for treating bone defects. Currently, there is growing trend in the application of modified Ilizarov methods (e.g., applying unilateral external fixators or with flap tissue) and its combined methods (e.g., Ilizarov method with antibiotic spacer or internal fixation) to manage bone defects. However, there is a lack of studies with systematical evaluation of the clinical effects of these evolving methods. This study aimed to conduct a systematic review and meta-analysis for overall evaluating the clinical effects on long bone defects of lower extremity in Ilizarov methods and its combined methods.

METHODS

Studies were identified in three electronic databases (Pubmed, Embase and Cochrane Library) from the earliest indexing year through November 01, 2022, and relevant data were extracted subsequently. The total number of participants, number of participants with bone unions, bone result or functional result, and related complications including pin infection, pin loosening, pain, refracture, limb discrepancy, malalignment, joint stiffness, recurrent infection, and amputation were extracted in this study. Then, union rate (defined as the proportion of patients who achieved bone unions) and specific complication incidence rate (defined as the proportion of patients who experienced specific complication) were pooled estimated respectively. Relative risk (RR) was used for comparing the clinical effects among various Ilizarov technique.

RESULTS

Sixty-eight case series studies, 29 comparative studies, and 3 randomized clinical trials were finally included. The union rate of Ilizarov methods was 99.29% (95% CI: 98.67% ~ 99.86%) in tibial defects and 98.81% (95% CI: 98.81% ~ 100.00%) in femoral defects. The union rate of Ilizarov method with antibiotic spacer and intramedullary nail in tibial defects was 99.58% (95% CI: 98.05% ~ 100.00%) and 95.02% (95% CI: 87.28% ~ 100.00%), respectively. Compared to the Ilizarov methods, the union rate of the Ilizarov method with antibiotic spacer in tibial defects increased slightly (RR = 1.02, 95% CI: 1.01 ~ 1.04). Meanwhile, compared to Ilizarov methods, we found lower excellent rate in bone result in Ilizarov method with antibiotic spacer, with the moderate to high heterogeneity. Compared to the Ilizarov method, lower rate of pin infection, higher rate of recurrent infection and amputation were observed in Ilizarov method with intramedullary nail, however, the findings about the comparison of pin infection and recurrent infection between the two groups were presented with high degree of statistical heterogeneity.

CONCLUSION

Our study confirmed the reliable treatment of Ilizarov methods and its combined technique on long bone defects, and founded there were significant differences on some complications rate between Ilizarov methods and its combined technique. However, the findings need to be confirmed by further studies.

Learning curve of tibial cortex transverse transport: a cumulative sum analysis

OBJECTIVE

This study aimed to describe the learning curve of surgeons performing tibial cortex transverse transport (TTT) and explore its safety and effectiveness during the initial stages of surgeon's learning.

METHODS

The clinical data of patients with diabetic foot ulcers classified as Wagner grade ≥ 2, who underwent TTT at our hospital from January 2020 to July 2021, were included in this retrospective analysis. The same physician performed all procedures. Patients were numbered according to the chronological order of their surgery dates. The cumulative sum and piecewise linear regression were used to evaluate the surgeon's learning curve, identify the cut-off point, and divide the patients into learning and mastery groups. A minimum follow-up period of 3 months was ensured for all patients. Baseline data, perioperative parameters, complications, and efficacy evaluation indicators were recorded and compared between the two groups.

RESULTS

Sixty patients were included in this study based on the inclusion and exclusion criteria. After completing 20 TTT surgeries, the surgeon reached the cut-off point of the learning curve. Compared to the learning group, the mastery group demonstrated a significant reduction in the average duration of the surgical procedure (34.88 min vs. 54.20 min, P < 0.05) along with a notable decrease in intraoperative fluoroscopy (9.75 times vs. 16.9 times, P < 0.05) frequency, while no significant difference was found regarding intraoperative blood loss (P = 0.318). Of the patients, seven (11.7%) experienced complications, with three (15%) and four cases (10%) occurring during the learning phase and the mastery phase, respectively. The postoperative ulcer area was significantly reduced, and the overall healing rate was 94.8%. Significant improvements were observed in postoperative VAS, ABI, and WIFI classification (P < 0.05). There were no significant differences in the occurrence of complications or efficacy indicators between the learning and mastery groups (P > 0.05).

CONCLUSION

Surgeons can master TTT after completing approximately 20 procedures. TTT is easy, secure, and highly efficient for treating foot ulcers. Furthermore, TTT's application by surgeons can achieve almost consistent clinical outcomes in the initial implementation stages, comparable to the mastery phase.

Complications associated with single-level bone transport for the treatment of tibial bone defects caused by fracture-related infection

BACKGROUND

The purpose of this study was to report the outcomes of single-level bone transport with a unilateral external fixator for treatment of proximal, intermediate and distal tibial bone defects caused by fracture-related infection (FRI) and compare their complications.

METHODS

The clinical records and consecutive X-ray photographs of patients with tibial bone defects treated by single-level bone transport using a unilateral external fixator (Orthofix Limb Reconstruction System) were analyzed retrospectively, from January 2012 to December 2018. Patients were divided into the proximal group (P, n = 19), intermediate group (I, n = 25), and distal group (D, n = 18) according to the location of the tibial bone defect. The Association for the Study and Application of the Method of Ilizarov (ASAMI) standard was applied to assess the bone and functional outcomes and postoperative complications evaluated by the Paley classification.

RESULTS

A total of 62 participants were included in this study, with a median age of 36 ± 7.14 years. Sixty patients with tibial bone defects caused by FRI were successfully treated by single-level bone transport using a unilateral external fixator, with a mean bone union time (BUT) of 7.3 ± 1.71 months. According to the ASAMI criteria, there were statistical differences in bone and function results between the three groups (P vs. I vs. D, P < 0.001). The excellent and good rate of bone result in the intermediate group was higher than the other (P vs. I vs. D, 73.6% vs. 84% vs. 66.7%), and the excellent and good rate of function result in the proximal group was the highest (P vs. I vs. D, 84.2% vs. 80% vs. 73.3%). Complications were observed in 29 out of 62 patients (46.7%), with pin tract infection being the most common (14.8%), followed by axial deviation (14.8%), muscle contractures (12.7%), joint stiffness (12.7%), and soft tissue incarceration (12.7%). Other complications included delayed consolidation (12.7%), delayed union (6.3%), nonunion (4.2%), and neurological injury (8.5%). Two patients (3.2%) required below-knee amputation due to uncontrollable infection and previous surgery failure.

CONCLUSIONS

Pin tract infection was the most common complication in tibial bone transport using an external fixator. Complications of distal tibial bone transport are more severe and occur at a higher rate than in other parts. Axial deviation mostly occurred in the intermediate tibial bone transport.

Matched-Pair Analysis: Large-Sized Defects in Surgery of Lower Limb Nonunions

BACKGROUND

The treatment of large-sized bone defects remains a major challenge in trauma and orthopaedic surgery. Although there are many treatment options, there is still no clear guidance on surgical management, and the influence of defect size on radiological and clinical outcome remains unclear due to the small number of affected patients. The aim of the present study was to determine the influence of defect size on the outcome of atrophic and infected nonunions of the tibia or the femur based on the diamond concept in order to provide recommendations for treatment guidance.

PATIENTS AND METHODS

All medical records, surgical reports, laboratory data and radiological images of patients treated surgically for atrophic or infected nonunions of the lower limbs (femur or tibia) between 1 January 2010 and 31 December 2020 were examined. Patients with proximal, diaphyseal or distal nonunions of the femur or tibia who were surgically treated at our institution according to the "diamond concept" and attended our standardised follow-up program were included in a database. Surgical treatment was performed as a one- or two-step procedure, depending on the type of nonunion. Patients with a segmental bone defect ≥5 cm were matched with patients suffering a bone defect <5 cm based on five established criteria. According to our inclusion and exclusion criteria, 70 patients with a bone defect ≥5 cm were suitable for analysis. Two groups were formed by matching: the study group (bone defect ≥5 cm; n = 39) and control group (bone defect <5 cm; n = 39). The study was approved by the local ethics committee (S-262/2017).

RESULTS

The mean defect size was 7.13 cm in the study and 2.09 cm in the control group. The chi-square test showed equal consolidation rates between the groups (SG: 53.8%; CG: 66.7%). However, the Kaplan-Meier curve and log-rank test showed a significant difference regarding the mean duration until consolidation was achieved, with an average of 15.95 months in the study and 9.24 months in the control group (α = 0.05, p = 0.001). Linear regression showed a significant increase in consolidation duration with increasing defect size (R² = 0.121, p = 0.021). Logistic regression modelling showed a significant negative correlation between consolidation rate and revision performance, as well as an increasing number of revisions, prior surgeries and total number of surgeries performed on the limb. Clinical outcomes showed equal full weight bearing of the lower extremity after 5.54 months in the study vs. 4.86 months in the control group (p = 0.267).

CONCLUSION

Surprisingly, defect size does not seem to have a significant effect on the consolidation rate and should not be seen as a risk factor. However, for the treatment of large-sized nonunions, the follow-up period should be prolonged up to 24 months, due to the extended time until consolidation will be achieved. This period should also pass before a premature revision with new bone augmentation is performed. In addition, it should be kept in mind that as the number of previous surgeries and revisions increases, the prospects for consolidation decrease and a change in therapeutic approach may be required.

Septic Tibial Nonunions on Proximal and Distal Metaphysis-A Systematic Narrative Review

BACKGROUND

Infected nonunion of the tibia represents a challenging complication for orthopedic surgeons and poses a major financial burden to healthcare systems. The situation is even more compounded when the nonunion involves the metaphyseal region of long bones, a rare yet demanding complication due to the poor healing potential of infected cancellous bone; this is in addition to the increased likelihood of contamination of adjacent joints. The purpose of this study was to determine the extent and level of evidence in relation to (1) available treatment options for the management of septic tibial metaphyseal nonunions; (2) success rates and bone healing following treatment application; and (3) functional results after intervention.

METHODS

We searched the MEDLINE, Embase, and CENTRAL databases for prospective and retrospective studies through to 25 January 2021. Human-only studies exploring the efficacy of various treatment options and their results in the setting of septic, quiescent, and metaphyseal (distal or proximal) tibia nonunions in the adult population were included. For infection diagnosis, we accepted definitions provided by the authors of source studies. Of note, clinical heterogeneity rendered data pooling inappropriate.

RESULTS

In terms of the species implicated in septic tibial nonunions, staphylococcus aureus was found to be the most commonly isolated microorganism. Many authors implemented the Ilizarov external fixation device with a mean duration of treatment greater than one year. Exceptional or good bone and functional results were recorded in over 80% of patients, although the literature is scarce and possible losses of the follow-up were not recorded.

CONCLUSION

A demanding orthopedic condition that is scarcely studied is infected metaphyseal tibial nonunion. External fixation seems promising, but further research is needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO No. CRD42020205781.

Clinical outcomes of bone transport using rail fixator in the treatment of femoral nonunion or bone defect caused by infection

Purpose

The rail fixator can improve the treatment outcome and provide good stability in patients with femoral bone transport. The purpose of this study is to investigate the clinical outcomes of bone transport using the Ilizarov technique by rail fixator in the treatment of femoral nonunion or bone defects caused by infection.

Methods

Clinical feature and treatment outcomes of 32 consecutive adult patients with femoral nonunion or bone defect caused by infection from January 2012 to January 2019 at a minimum of 2 years of follow-ups were retrospectively analyzed. Data were collected on participants' demographic details. All difficulties related to bone transport were documented according to Paley's classification. The clinical outcomes were evaluated using ASAMI criteria at the last clinical visit.

Results

All 32 patients with an average follow-up of 33.5 months. There were 17 problems, 21 obstacles, and 8 complications, and the complication rate per patient was 1.4. The main complications were pin-site infection (53.1%), axial deviation (21.9%), joint stiffness (18.8%), the delayed union of the docking site (18.8%), soft tissue incarceration(15.6%), delayed consolidation(6.3%), malunion(6.3%), and refracture (3.1%). All the patients achieved bone union, and no recurrence of infection was observed. The excellent and good rates of ASAMI bone and functional results were 87.5% and 81.3%, respectively.

Conclusion

Bone transport using the Ilizarov technique is an effective method for the treatment of femoral nonunion or bone defect caused by infection, and rail fixators have obtained satisfactory results in terms of bone and functional results.

Bone Transport Treatment of Osteomyelitis Due to Thermal Osteonecrosis After IM Nailing of Tibial Stress Fracture Nonunion: A Case Report

CASE

We present a case of a female athlete who sustained a nonunion of a tibial stress fracture and was treated with intramedullary nailing (IMN). The patient developed osteomyelitis likely secondary to a thermal osteonecrosis during the index procedure and required resection of the necrotic tibia and bone transport using the Ilizarov technique.

CONCLUSIONS

The authors believe that all actions should be taken to avoid thermal osteonecrosis during reaming for tibial IMN, especially in patients with a small medullary canal. We believe that bone transport with the Ilizarov technique is an effective treatment method for patients who develop tibial osteomyelitis after treatment of tibial shaft fractures.

Functional outcomes and health-related quality of life after reconstruction of segmental bone loss in femur and tibia using the induced membrane technique

INTRODUCTION

The induced membrane technique (IMT), frequently called Masquelet technique, is an operative, two-staged technique for treatment of segmental bone loss. Previous studies mainly focused on radiological outcome parameters and complication rates, while functional outcomes and health-related quality of life after the IMT were sparsely reported.

MATERIALS AND METHODS

Retrospective study containing of a chart review as well as a clinical and radiological follow-up examination of all patients treated with the IMT at a single institution. The clinical outcomes were evaluated using the Lower Extremity Functional Scale (LEFS), the Short-Form-36 (SF-36) and the visual analog scale (VAS) for pain. The radiographic evaluation contained of standard anteroposterior and lateral, as well as hip-knee-ankle (HKA) radiographs.

RESULTS

Seventeen patients were included in the study. All had suffered high-energy trauma and sustained additional injuries. Ten bone defects were localized in the femur and seven in the tibia. Ten patients underwent additional operative procedures after IMT stage 2, among them three patients who contracted a postoperative deep infection. The median LEFS was 59 (15-80), and the SF-36 physical component summary (PCS) and mental component summary (MCS) were 41.3 (24.0-56.1) and 56.3 (13.5-66.2), respectively. The median length of the bone defect was 9 (3-15) cm. In 11 patients, union was obtained directly after IMT stage 2. Bone resorption was observed in two patients. At follow-up, 16 of the 17 bone defects had healed. The median follow-up was 59 months (13-177).

CONCLUSION

Our results show a high occurrence of complications after IMT stage 2 in segmental bone defects of femur and tibia requiring additional operative procedures. However, fair functional outcomes as well as a good union rate were observed at follow-up.

Application of Hydrogels as Sustained-Release Drug Carriers in Bone Defect Repair

Large bone defects resulting from trauma, infection and tumors are usually difficult for the body's repair mechanisms to heal spontaneously. Generally, various types of bones and orthopedic implants are adopted to enhance bone repair and regeneration in the clinic. Due to the limitations of traditional treatments, bone defect repair is still a compelling challenge for orthopedic surgeons. In recent years, bone tissue engineering has become a potential option for bone repair and regeneration. Amidst the various scaffolds for bone tissue engineering applications, hydrogels are considered a new type of non-toxic, non-irritating and biocompatible materials, which are widely used in the biomedicine field currently. Some studies have demonstrated that hydrogels can provide a three-dimensional network structure similar to a natural extracellular matrix for tissue regeneration and can be used to transport cells, biofactors, nutrients and drugs. Therefore, hydrogels may have the potential to be multifunctional sustained-release drug carriers in the treatment of bone defects. The recent applications of different types of hydrogels in bone defect repair were briefly reviewed in this paper.

Risk factors of transport gap bending deformity in the treatment of critical-size bone defect after bone transport

Background

The purpose of this study was to investigate the risk factors of transport gap bending deformity (TGBD) in the treatment of critical-size bone defect (CSBD) after the removal of the external fixator.

Methods

From January 2008 to December 2019, 178 patients with bone defects of the lower extremity caused by infection were treated by bone transport using a unilateral external fixator in our medical institution. TGBD was defined as the bone callus in the distraction area with a deviation to the force line of the femur (> 10°) or tibia (> 12°) after removal of the external fixator. The Association for the Study and Application of the Method of Ilizarov (ASAMI) standard was applied to assess the bone and functional outcomes. After the data were significant by the T-test or Pearson’s Chi-square test was analyzed, odds ratios were calculated using logistic regression tests to describe factors associated with the diagnosis of TGBD.

Results

A total of 178 patients were enrolled in the study, with a mean follow-up time of 28.6 ± 3.82 months. The positive result of the bacteria isolated test was observed in 144 cases (80.9%). The rate of excellent and good in the bone outcomes (excellent/good/fair/poor/failure, 41/108/15/14/0) was 83.7%, and 92.3% in the functional results (excellent/good/fair/poor/failure, 50/98/16/14/0) according to the ASAMI criteria. TGBD after removal of external fixator occurred in twenty-two patients (12.3%), including 6 tibias, and 16 femurs. Age > 45 years, BMI > 25 kg/m², femoral defect, diabetes, osteoporosis, glucocorticoid intake, duration of infection > 24 months, EFT > 9 months, EFI > 1.8 month/cm were associated significantly with a higher incidence of TGBD in the binary logistic regression analysis (P < 0.05). The incidence more than 50% was found in patients with femoral defect (76.1%), osteoporosis (72.7%), BMI > 25 kg/m² (69.0%), diabetes (59.5%), glucocorticoid intake (54.7%). In the multivariate logistic regression analyses, the following factors were associated independently with TGBD, including age > 45 years, BMI > 25 kg/m², femoral defect, diabetes, and osteoporosis.

Conclusions

Bone transport using a unilateral external fixator was a safe and practical method in the treatment of CSBD caused by infection. The top five risk factors of TGBD included femoral defect, BMI > 25 kg/m², duration of bone infection > 24 months, age > 45 years, and diabetes. Age > 45 years, BMI > 25 kg/m², femoral defect, osteoporosis, and diabetes were the independent risk factors. The higher incidence of TGBD may be associated with more risk factors.

Shortening and re-lengthening versus bone transport for the treatment of distal tibial periarticular post-traumatic defects

In the present study, we presented our experience with a new modified technique of shortening and re-lengthening using a monolateral external frame combined with a calcaneal intramedullary nail and compared it with the bone transport technique for the treatment of distal tibial periarticular post-traumatic defects. Forty-one patients were retrospectively analyzed. Among them 19 were treated using our modified shortening and re-lengthening technique (MSR group) and 22 by bone transport (BT group). The difference in external fixation time (EFT), external fixation index (EFI), self-rating anxiety scale (SAS), and complications were compared between the two groups. The mean EFT was 3.4 ± 0.6 months in the MSR group and 7.5 ± 1.4 months in the BT group; the EFI was 0.57 ± 0.06 month/cm and 1.32 ± 0.23 month/cm, respectively. The EFT, EFI, and SAS scores were significantly lower in the MSR group than in the BT Group (p < 0.05). The mean number of complications per patient in the BT group was nearly 2.4 times that of the MSR group (p < 0.05). Our modified shortening and re-lengthening technique reduced the EFI and complication incidence compared to the bone transport technique. Therefore, patients with distal tibial periarticular post-traumatic defects can achieve great satisfaction with this new technique.

Nonunion of the femoral shaft associated with limb shortening treated with a combined technique of external fixation over an intramedullary nail versus the Ilizarov method

INTRODUCTION

Post-traumatic nonunion of the femur remains a challenging problem even for experienced orthopedic surgeons. The main question is the choice of the optimal surgical tool.

MATERIALS AND METHODS

Management of 20 patients with nonunion of the femoral diaphysis associated with anatomical shortening was retrospectively analyzed. Group A (n = 14) was treated with a hybrid technique that combined the Ilizarov external fixation and intramedullary nailing. The Ilizarov bone transport was used in group B (n = 6). Patients of both groups had aseptic post-traumatic nonunion. Mean shortening was 4.5 ± 0.4 cm in group A and 4.8 ± 1.0 cm in group B (p = 0.459959).

RESULTS

Union was achieved in 85.7% of group A and 100% of group B patients. External fixation was repeated in two cases of group A and achieved consolidation. Deep infection developed in one case of group A after 15 months post-frame with the nail in. It was resolved by nail removal, surgical debridement and external fixation. Limb shortening was fully eliminated in eleven cases of group A and four patients of group B. The average duration of distraction was 35.3 ± 1.7 days in group A and 47.8 ± 9.3 days in group B. The total duration of external fixation was 49.1 ± 3.5 and 177.2 ± 21.9 days with an external fixation index of 13.1 ± 1.2 and 52.4 ± 6.4 days/cm, respectively. Distraction regenerate consolidated in all the cases.

CONCLUSION

Hybrid technique provides bone union with compensation of limb shortening and reduces the treatment period as compared with the Ilizarov method used alone. However, deep infection may happen.

Management of Elderly Traumatic Ankle Arthritis with Ilizarov External Fixation

Objective

To evaluate the clinical curative effect of Ilizarov external fixation and ankle arthrodesis in the treatment of elderly traumatic ankle arthritis.

Methods

From June 2013 to August 2019, 72 patients with elderly traumatic ankle arthritis were treated with arthrodesis through Ilizarov external fixation technique in our institution. Conventional double‐feet standing X‐ray films were taken before and after operation. The tibiotalar angle on X‐ray image was measured to evaluate the degree of talipes varus and valgus. The Foot and Ankle pain score of American Orthopaedics Foot and Ankle Society (AOFAS) and Visual Analog Scale (VAS) were compared by using paired t‐test to evaluate the functional recovery.

Results

All of the patients acquired effective postoperative 18–49 months follow‐up, with an average of 31.5 months. All patients were included in the analysis, among which 38 cases were males and 34 cases were females, with an average of 65.4 years (ranging from 60 to 74). All ankles achieved bony fusion; the clinical healing time was 12.7 weeks on average (11–18 weeks). The AOFAS score was 45.36 ± 6.43 preoperatively and 80.25 ± 9.16 at 12 months post‐operation, with a statistically significant difference (p < 0.0001). The VAS score was 8.56 ± 1.85 on average preoperatively and 2.72 ± 0.83 at 12 months post‐operation, with a statistically significant difference (p < 0.0001). The tibiotalar angle was 101.93° ± 4.12° preoperatively and 94.45° ± 2.37° at 12 months post‐operation, with a statistically significant difference (p < 0.0001). The results of the functional evaluation indicated that 44 patients (61.1%) had excellent results, 18 (25%) had good results, and 10 (13.9%) had fair results.

Conclusion

Our study demonstrated that it is possible to obtain satisfactory outcome with Ilizarov external fixation and ankle arthrodesis in the treatment of elderly traumatic ankle arthritis.

Therapeutic Efficacy and Safety of Osteoinductive Factors and Cellular Therapies for Long Bone Fractures and Non-Unions: A Meta-Analysis and Systematic Review

Background: Long bone fractures display significant non-union rates, but the exact biological mechanisms implicated in this devastating complication remain unclear. The combination of osteogenetic and angiogenetic factors at the fracture site is an essential prerequisite for successful bone regeneration. The aim of this study is to investigate the results of the clinical implantation of growth factors for intraoperative enhancement of osteogenesis for the treatment of long bone fractures and non-unions. Methods: A systematic literature review search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the PubMed and Web of Science databases from the date of inception of each database through to 10 January 2022. Specific inclusion and exclusion criteria were applied in order to identify relevant studies reporting on the treatment of upper and lower limb long bone non-unions treated with osteoinductive or cellular factors. Results: Overall, 18 studies met the inclusion criteria and examined the effectiveness of the application of Bone Morphogenetic Proteins-2 and -7 (BMPs), platelet rich plasma (PRP) and mesenchymal stem cells (MSCs). Despite the existence of limitations in the studies analysed (containing mixed groups of open and close fractures, different types of fractures, variability of treatment protocols, different selection criteria and follow-up periods amongst others), their overall effectiveness was found significantly increased in patients who received them compared with the controls (I² = 60%, 95% CI = 1.59 [0.99–2.54], Z =1.93, p = 0.05). Conclusion: Administration of BMP-2 and -7, PRP and MSCs were considered effective and safe methods in fracture treatment, increasing bone consolidation, reducing time to repair and being linked to satisfactory postoperative functional scores.

A meta-analysis of the Masquelet technique and the Ilizarov bone transport method for the treatment of infected bone defects in the lower extremities

Purpose:To compare the clinical outcomes of the Masquelet technique and Ilizarov bone transport method for the treatment of patients with infected bone defects in the lower extremities. Methods: Eligible studies were searched from six databases until 12 April 2021. Data extraction was independently conducted by two investigators, which was followed by a quality assessment. Weighted mean difference (WMD) and 95% confidence interval (CI) were used to analyze continuous variables, while odds ratio (OR) and 95% CI were used to analyze categorical variables. All statistical analyses were conducted using RevMan 5.3 and Stata 12.0. Results: Thirteen articles were included in this meta-analysis. There was a significant difference observed in hospitalization costs (WMD [95% CI] = -1.75 [-2.50, -0.99] thousand US dollar, p < 0.00,001), final union time (WMD [95% CI] = -4.54 [-6.91, -2.17] months, p = 0.0002), time to full weight bearing (WMD [95% CI] = -1.73 [-3.36, -0.10] months, p = 0.04), quality of life (WMD [95% CI] = 7.70 [4.74, 10.67], p < 0.00,001), and the risk of complications (OR [95%CI] = 0.39 [0.19, 0.79], p = 0.009) between the Masquelet and Ilizarov groups. No significant differences in other outcomes were observed between the two groups. Conclusion: Masquelet technique exhibited the advantages in the lower hospitalization cost, shorter final union time, shorter time to full weight bearing, lower rate of complications, and better post-operative quality of life, compared with Ilizarov bone transport method. However, this finding should be confirmed in large-scale clinical samples.

Long-term sequelae of septic arthritis after tibial plateau fracture fixation: does timing matter?

INTRODUCTION

Septic arthritis following surgical treatment of a tibial plateau fracture is a rare complication, but it does occur, and the impact on long-term function is relatively unknown. The purpose of this study was to determine the long-term sequelae of septic arthritis among patients treated with internal fixation for a tibial plateau fracture and to determine the effect of timing (early or late infection) on the rate of such sequela.

MATERIALS AND METHODS

A retrospective comparative study was designed using the trauma database of a single level I academic trauma center. Patients who developed culture-positive septic knee arthritis after internal fixation of a tibial plateau fracture, with 1-year follow-up, were included in the study. The number of debridement procedures required was recorded. Rates of long-term complications and implant removal were identified. Complications rates were compared between patients who developed early (within 30 days of definitive fixation) and late (more than 30 days) septic arthritis.

RESULTS

The mean number of debridement procedures per patient was six. Fourteen patients (88%) required implant removal, and thirteen (81%) developed knee arthritis. There was a significantly lower rate of complications in the early septic arthritis group compared to the late group (3 of 6 patients or 50%, vs 10 of 10 patients or 100%; p = 0.036).

CONCLUSIONS

Patients who developed septic arthritis following internal fixation of a tibial plateau fracture were likely to endure long-term sequelae. Early infection and detection led to fewer complications. Surgeons treating infectious complications in tibial plateau fracture patients should specifically seek to rule out septic arthritis, anticipate that implant removal may be necessary, and counsel these patients appropriately regarding the anticipated natural history of their condition.

LEVEL OF EVIDENCE

III.

Bone Defects in Tibia Managed by the Bifocal vs. Trifocal Bone Transport Technique: A Retrospective Comparative Study

Background

The purpose of this study is to evaluate the clinical effectiveness and determine the differences, if any, between the trifocal bone transport (TFT) technique and the bifocal bone transport (BFT) technique in the reconstruction of long segmental tibial bone defects caused by infection using a monolateral rail external fixator.

Methods

A total of 53 consecutive patients with long segmental tibial bone defects caused by infection and treated by monolateral rail external fixator in our department were retrospectively collected and analyzed from the period January 2013 to April 2019, including 39 males and 14 females with an average age of 38.8 ± 12.4 years (range 19–65 years). Out of these, 32 patients were treated by the BFT technique, and the remaining 21 patients were managed by the TFT technique. The demographic data, operation duration (OD), docking time (DT), external fixation time (EFT), and external fixation index (EFI) were documented and analyzed. Difficulties that occur during the treatment were classified according to Paley. The clinical outcomes were evaluated by following the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria at the last clinical visit.

Results

All patients achieved an infection-free union finally, and there was no significant difference between the two groups in terms of demographic data and both ASAMI bone and functional scores (p > 0.05). The mean defect size and OD in TFT (9.4 ± 1.5 cm, 161.9 ± 8.9 min) were larger than that in BFT (7.8 ± 1.8 cm, 122.5 ± 11.2 min) (p < 0.05). The mean DT, EFT, and EFI in TFT (65.9 ± 10.8 days, 328.0 ± 57.2 days, 34.8 ± 2.1 days/cm) were all less than those in BFT (96.8 ± 22.6 days, 474.5 ± 103.2 days, 60.8 ± 1.9 days/cm) (p < 0.05). Difficulties and complications were more prevalent in the BFT group than in the TFT group (p < 0.05).

Conclusion

Both the trifocal and BFT techniques achieve satisfactory clinical outcomes in the reconstruction of long segmental tibial bone defects caused by infection using a monolateral rail external fixator. The TFT technique can significantly decrease the DT, EFT, EFI, difficulties, and complications compared with the BFT technique.

Efficacy comparison of trifocal bone transport using unilateral external fixator for femoral and tibial bone defects caused by infection

BACKGROUND

This study aimed to evaluate the clinical and functional outcomes of patients with femoral and tibial critical-sized bone defect (CSBD) treated by trifocal bone transport using the Ilizarov method.

METHODS

From March 2011 and January 2017, clinical and radiographic data of patients with CSBD (> 6 cm) caused by infection were documented and analyzed. Patients were divided into the femur group (n = 18) and tibia groups (n = 21) according to the location of bone transport. The bone and functional outcomes were evaluated according to the Association for the Study and Application of the Method of the Ilizarov (ASAMI) criterion, and postoperative complications were evaluated by Paley classification.

RESULTS

A total of 39 patients were managed by the trifocal bone transport for the femur (n = 18) or tibia (n = 21) bone defects with a mean follow-up time of 26.1 months (range 17-34 months). Eighteen femurs and 21 tibias with a mean distraction regenerate length (DRL) of 8.3 cm (range 6-13 cm) and 7.5 cm (range 6-11 cm) respectively. Infection was eradicated in all patients, and the total bone union was received in all cases (100%). Statistical difference of bone grade (excellent/good/fair/poor, 3/11/3/1 vs 2/13/4/2, P < 0.05), and function grade (excellent/good/fair/poor, 3/14/1/0 vs 4/13/3/1, P < 0.05) were respectively observed between the femur group and tibia group. The excellent and good rate of bone (femur vs tibia, 77.8% vs 71.4%), and function grade (femur vs tibia, 94.4% vs 80.9%) was higher in the femur group than the tibia. The rate of complication in the femur group was lower than in the tibia (femur vs tibia, 94.4% vs 76.2%). One femur and five tibias were performed additional surgery for delayed union and axial deviation.

CONCLUSIONS

The trifocal bone transport using the unilateral external fixator was a practical method in the management of CSBD in the lower extremity. The BUT and EFI of the femur group were shorter than the tibia. Although the complications noted were more frequent on the femur, these were mostly minor.

One-stage combined "fix and flap" approach for complex open Gustilo-Anderson IIIB lower limbs fractures: a prospective review of 102 cases

BACKGROUND

Management of open fractures is challenging and requires a multidisciplinary team approach. This study aims to evaluate outcomes of open Gustilo-Anderson IIIB fractures managed at a single Ortho-Plastic centre following One-stage "Fix and Flap" approach.

METHODS

Prospective data review for patients presenting with Gustilo-Anderson IIIB Fractures to our centre and managed with one-stage "Fix and Flap" approach. Postoperative outcomes are presented only for the patients who had a minimum of 12 months postoperative follow-up.

RESULTS

120 patients were included (83 males and 37 females). Mean age was 43 years (10-96). Tibia diaphysis was the most common site of injury (60%). 55.9% of injuries were road traffic accidents (RTA). 102 out of 120 patients had a minimum of 12 months follow-up (mean follow-up duration 25 months). Meantime from injury until definitive surgery was 7.71 days. Primary union achieved in 86.73%. Delayed union was encountered in 10.20%. 3.06% of patients had non-union. Limb salvage rate was 97.05% and Deep infection rate was only 0.98%.

CONCLUSION

Our results showed that low infection rate, high limb salvage rate, and high union rate can be achieved in these complex injuries with meticulous technique, combined Ortho-Plastic (Fix and Flap) approach, and MDT input.

Evaluation of complications associated with bifocal bone transport as treatment for either proximal, intermediate or distal femoral defects caused by infection: outcome analysis of 76 patients

Background

The purpose of this study was to evaluate the outcomes of bifocal bone transport in the treatment of femoral bone defects caused by infections.

Methods

Clinical and radiographic data of patients with infected femoral nonunion treated by the bifocal bone transport at our hospital were analyzed retrospectively, from January 2008 to December 2019. Depending on the location of bone defects, the patients were divided into three groups (proximal, intermediate, and distal). The Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria was applied to assess the bone and functional outcomes. Postoperative complications of three groups were documented and compared.

Results

Seventy-six cases of infected femoral bone defects (31 cases of proximal, 19 cases of intermediate, and 26 cases of distal) were managed by bifocal bone transport successfully with a mean follow-up time of 30.8 months (range, 23 to 41 months). There were 58 men (76.3%) and 18 women (23.6%), with a mean age of 38.8 years (range, 23 to 60 years). The bone union was received in 76 cases with a mean of 6.9 months (range, 5 to 8 months). Pin tract infection was observed in twenty-nine cases (38.1%), 7 cases (9.2%) of muscle contractures, 3 cases (7.9%) of joint stiffness, 13 cases (17.1%) of axial deviation, 2 cases (2.6%) of delayed union, one case (1.3%) of nonunion, and none (0%) of transport gap re-fracture. One patient (1.3%) was scheduled for knee arthroplasty when bone transport treatment ended.

Conclusions

Bone transport using an external rail fixator was a practical method to treat the femoral bone defects, since the satisfactory rate of bone union and limb function recovery. Complications of distal femoral bone transport were more severe than the proximal and intermedia, but the rate of complication was the least of the three groups. Soft-tissue-related complications were more likely to occur in the intermediate bone transport.

Cyclic Distraction–Compression Dynamization Technique Enhances the Bone Formation During Distraction Osteogenesis

Background: Interfragmentary movements have benefits in the improvement of bone formation during distraction osteogenesis (DO). Although several clinical studies reported positive outcomes regarding the application of the cyclic distraction–compression (CDC) dynamization technique in cases with poor bone formation during DO, they are mostly anecdotal without a detailed description. The purpose of this study was to investigate the effectiveness and potential mechanism of different amplitudes and rates of the CDC technique on bone regeneration in a rat femur DO model.

Methods: A total of 60 adult male Sprague-Dawley rats underwent right femoral mid-diaphysis transverse osteotomy and were randomly and evenly divided into Control (no manipulation), Group1 (CDC therapy), Group2 (CDC therapy with larger amplitude), and Group3 (CDC therapy with a slower rate) after distraction. The CDC technique was performed during the middle phase of the consolidation period according to different protocols. Animals were sacrificed after 4 and 6 weeks of consolidation. The process of bone formation was monitored by digital radiographs, and the regenerate bone was evaluated by micro-computed tomography (micro-CT), biomechanical test, and histological analysis. The serum contents of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) were measured by enzyme-linked immunosorbent assay (ELISA).

Results: Bone regeneration after the CDC technique was improved significantly during DO. The digital radiograph, micro-CT, histomorphological analysis, and biomechanical evaluation showed better effects regarding volume, continuity, and mechanical properties of the regenerate bone in Group2 and Group3 when compared to Group1. The angiogenic and osteogenic markers were more highly expressed in Group2 and Group3 than in Group1 according to the immunohistochemical analysis. As for ELISA, the serum contents of HIF-1α and VEGF were also increased after the CDC technique, especially in Group2 and Group3.

Conclusion: The CDC dynamization technique has benefits on the improvement of bone formation during DO, and the mechanism may be due to tissue hypoxia activating the HIF pathway followed by the augmentation of osteogenic–angiogenic coupling. Better outcomes may be achieved by moderately increasing the amplitude and slowing down the rate of the CDC technique.

Risk factors of pin tract infection during bone transport using unilateral external fixator in the treatment of bone defects

Background

The bone transport using the unilateral external fixator, one of the Ilizarov techniques, is widely practiced in lower limb reconstructive surgery. Pin tract infection (PTI), one of most common complication, has become the important postoperative problems which plague clinicians gradually.

Methods

A group of 130 patients who received bone transport surgery for tibia or femur defects using the unilateral external fixation (Orthofix limb reconstruction system, Verona, Italy) and met the inclusion criteria were selected for the study from 2015 to 2019. Regular pin tract care was performed twice a day, and the conditions of the pin tract were evaluated by the same observer using clinical appearance criteria. The Saw’s classification of PTI was used to assess the condition around screws. After the data were significant by the T-test or Pearson’s Chi-square test analyzed, odds ratios were calculated using logistic regression tests to describe factors associated with the diagnosis of PTI.

Results

Ninety-one males and thirty-nine females with a mean age of 43 years (range 28–58 years) were included in this cohort. 7816 observations were documented from 12 to 36 months, and 58 cases (44.6%) of PTI (thirty-nine cases in grade 1, 17 cases in grade 2, and 2 cases in grade 3). The top five risk factors were agricultural work (OR 1.86, CI 0.94–2.39), non-urban living (OR 1.75, CI 1.24–3.26), male (OR 1.71, CI 1.02–2.31), smoking (OR 1.53, CI 0.76–1.89), and diabetes (OR 1.26, CI 1.12–2.64). No long-term sequelae were observed at the latest clinical visit.

Conclusion

Occupation, gender, living environment (non-urban), smoking, and diabetes were the top five significant risk factors for PTI in the period of bone transport using unilateral external fixation. Awareness of predictable risk factors of PTI is beneficial to avoid or early detect the severe complications which can affect the effectiveness.

International recognition of the Ilizarov bone reconstruction techniques: Current practice and research (dedicated to 100th birthday of G. A. Ilizarov)

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed “limb lengthening and reconstruction surgery”. Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal’s rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.

Risk factors of ankle osteoarthritis in the treatment of critical bone defects using ilizarov technique

Background

Distraction osteogenesis using the Ilizarov external circular fixator has been applied in lower limb reconstructive surgery widely. The increasing ankle osteoarthritis (OA) progression and severity are often associated with the period of external fixator and the greater relative instability of the ankle joint, but few studies have quantified risk factors directly during this technique.

Methods

The study was conducted on 236 patients who underwent bone transport surgery for tibias using the Ilizarov external circular fixator from 2008 to 2018. The cumulative incidence of ankle OA diagnoses in patients after the Ilizarov technique treatment was calculated and stratified by risk factors from preoperative and postoperative management. After the data were significant through the Mann-Whitney U test analyzed, odds ratios were calculated using logistic regression to describe factors associated with the OA diagnosis including gender, age, BMI, location of bone defect, diabetes, hypertension, osteoporosis, the history of metal allergy and glucocorticoid intake, the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-HF scale scores, defect size (DS), the type of bone transport, the bone union time, external fixator time (EFT), and external fixator index (EFI).

Results

There were 199 males and 37 females with a mean age of 47 years (range 28–59 years). Out of 236 patients, 49 had an additional treatment for ankle OA after the Ilizarov technique treatment of bone defects (average follow-up time 2.1 years, range 1.6–4.2 years). The incidence of postoperative ankle OA was 20.8 %, with 19 patients classified as K&L grade 3 and seven patients as grade 4. The top five risk factors included double-level bone transport (OR3.79, P = 0.005), EFI > 50days/cm (OR3.17, P = 0.015), age > 45years (OR2.29, P = 0.032), osteoporosis (OR1.58, P < 0.001), BMI > 25 (OR1.34, P < 0.001). Male, BMI > 25, diabetes, osteoporosis, and AOFAS ankle-HF scale scores are the independent risk factors.

Conclusions

Ilizarov external circular fixator is a safe and effective method of treatment for critical bone defects. The double level bone transport, EFI > 50days/cm, age > 45years, osteoporosis, BMI > 25 are the top five relevant risk factors of ankle OA. The probability of developing ankle OA among patients having three or more risk factors is 50–70 %.