Large Tibial Defects Research Articles

Open segmental tibial bone defects treated with Ilizarov frame: a radiological and functional outcome study with average ten year follow-up.

Surgical reconstruction of large post-traumatic tibial bone and soft tissue defects following high-energy trauma presents a significant challenge for orthopaedic surgeons. This study aimed to evaluate the functional and radiological outcomes of large post-traumatic tibial bone and soft tissue defects managed by single or double-level bone transport using the Ilizarov technique. 13 patients who underwent treatment for large tibial bone defects (Gustillo IIIa, IIIb, IIIc) along with soft tissue defects with Ilizarov from 2010 to 2020A.D were included. ASAMI functional and radiological outcomes were assessed at the final follow-up to report the outcome. The mean age was 27.38 (18-48). An average bone defect was 7.69cm (5-13cm). Based upon the Gustillo-Anderson classification (GA), 2 (15%) of them were GA - 3A, 7 (54%) were GA - 3B, and 4 (31%) were GA - 3C. The average time of distraction was 11.76 weeks (8-16). The average time for the union was 37 weeks (27-48 weeks). The average bone lengthening was 7.69cm (5-13cm). The mean final leg length discrepancy (LLD) at the final follow-up was 1.96cm (0-4cm). The primary union was achieved in eight cases, and five required bone grafting at the docking site. Using the ASAMI (Association for the Study of the Method of Ilizarov) scoring system, the functional results were excellent in six and good in seven cases, while the bony results were excellent in eight, good in four and fair in one case. Good to excellent functional and radiological scores (ASAMI) can be expected when using the Ilizarov frame for simultaneous treatment of the large tibial bone and soft tissue defect when this method is applied with correct principles.

Gradual Transverse Transport of Naturally Tibialized Fibula Using Hexapod Frames to Treat Neglected Type V Tibial Segmental Defects.

Although several reconstructive methods have been developed to manage large segmental tibial bone defects including bone transport (distraction osteogenesis), contralateral fibular graft, allograft, tibiofibular synostosis, Masquelet technique, and 3D printed scaffold, neglected large tibial defects in adults remain challenging problems. This study describes gradual transverse transport of naturally tibialized fibula using hexapod frames in management of adult patients with neglected large tibial defects. We retrospectively reviewed four cases of transverse transport of naturally tibialized fibula from November 2018 to February 2022. We measured the length of the tibial defect and the transported fibular segment, the mid-diaphyseal diameter and cortical thickness of the affected fibula, contralateral fibula, and tibia. The parameters measured both preoperatively and postoperatively were leg length discrepancy, hip-knee-ankle angle, medial proximal tibial angle, posterior proximal tibial angle, lateral distal tibial angle, range of motion of the knee and ankle joints, and Lower Extremity Functional Scores (LEFS). Patients' satisfaction rates using Likert scale were also recorded. Among four female patients, three suffered from tibial osteomyelitis, and one was due to congenital pseudarthrosis of the tibia. The average follow-up time was 2.7 ± 1.4 years. The average length of tibial defect was 14.0 ± 0.8 cm. The average preoperative shortening of the affected leg was 9.0 ± 2.5 cm, which changed to 0.6 ± 0.8 cm postoperatively. The median length of the transported fibular segment was 15.2 cm. Two patients had varus deformity, two had recurvatum, and one had procurvatum preoperatively. Postoperative radiological measurement showed all deformities corrected and no ankle valgus deformity developed during follow-up. All patients achieved union and can fully weight bear on the affected extremity. The average fixator time was 12.9 ± 2.9 months. The average preoperative and postoperative LEFS, respectively, were 53.5 ± 5.0, 70.5 ± 1.3, with a significant difference (p = 0.003). Three patients reported very satisfied with the outcome, and one patient reported satisfied. Three patients had pin tract infections, and one patient had skin necrosis which healed after additional surgery. One patient had surgical release of the hamstring tendons due to flexion contracture of the knee. Two patients had 15° of reduction in ankle range of motion. One patient had transient common peroneal nerve palsy which spontaneously recovered within 6 weeks. The transverse transport of naturally tibialized fibula was both a safe and effective method to treat the long-standing type V tibial segmental defect.

Semi-focal bone transport versus traditional bone transport technique for the management of large tibial bone defects after trauma

How to deal with large tibial bone defects is still controversial. The purpose of this research was to compare the semi-focal bone transport (SFBT) technique with traditional bone transport (TBT) technique for treating such patients. Sixty-two patients were included and retrospectively analyzed. In all cases, after radical debridement large tibial bone defects remained. Patients were treated by the SFBT or TBT technique. The distraction, consolidation duration and complications were recorded by the patients’ medical files. Based on the Association for the Study and Application of Methods of Ilizarov (ASAMI) standard, the bone and functional results were evaluated. The mean bone defect size was 7.7 ± 1.6 cm and 7.5 ± 2.1 cm for SFBT and TBT patients. The mean external fixation index (EFI) was 1.51 ± 0.14 months/cm and 1.89 ± 0.25 months/cm for SFBT and TBT patients (p < 0.05), respectively. With respect to bone and function results, there was no significant differences between the two groups (p > 0.05). The mean number of complications per patient was 1.1 ± 0.6 and 1.6 ± 0.7 for SFBT and TBT patients (p < 0.05). Compared to the traditional bone transport technique, patients using the semi-focal bone transport technique achieved better clinical effects, including shorter EFI and less complications. Therefore, the SFBT technique could be a new option for patients with large tibial bone defects.

Induced membrane technique with plate fixation has a lower complication rate than bone transport over a plate for segmental tibial defects larger than 5cm.

The treatment of segmental tibial bone defects remains a surgical challenge. While Bone Transport (BT) and Induced Membrane Technique (IMT) are effective strategies for regenerating bone, there are few comparative studies between them. This investigation undertakes a comparative analysis of BT and IMT for large segmental tibial defects stabilised through plate fixation. Patients with segmental tibial defects exceeding 5cm were prospectively enrolled from 2008 to 2021 in a single institution, with a minimum follow-up duration of two years. All patients underwent either BT or IMT with plate fixation of the tibia. Procedural success, primary union as well as bone and functional outcome scores were compared. Complications, including non-unions, joint contractures and deep infections requiring surgical intervention, were also compared. 41 patients were recruited in total. 28 patients underwent Bone Transport Over a Plate (BTOP), while 13 patients underwent IMT with Plate fixation (IMTP). The procedural success rate trended higher in IMTP compared to BTOP (100% vs. 85.7%). The primary union rate also trended higher in IMTP compared to BTOP (92.3% vs. 79.2%). BTOP and IMTP achieved similar rates of satisfactory bone outcome scores (78.6% vs. 84.6%) and functional outcome scores (75% vs. 76.5%). There was no statistical difference between procedural success, primary union, bone and functional outcome scores. The complication rate in BTOP was 78.6% (22 of 28), including five docking site or regenerate non-unions, eight deep infections and nine joint contractures. IMTP had a 38.5% (5 of 13) complication rate, including one non-union, two deep infections and two joint contractures. The complication rate was 2.04 times higher in BTOP compared to IMTP (p = 0.0117). BTOP and IMTP are both equally effective techniques for regenerating bone in large tibial bone defects. However, IMTP may be a safer procedure than BTOP, with a lower probability of requiring additional procedures to address complications.

Can locking plate fixation and free Vascularised fibular transfer with skin island achieve good functional outcome in the treatment of large bone defects of Tibia ? A study of 26 cases

BackgroundDespite the availability of multiple treatment options, management of tibial bone loss continues to be a challenge. Free vascularized fibula graft (FVFG) with a skin paddle offers better advantages over the other methods. We aimed to study the functional outcomes and QALY of patients with large tibial bone defects following FVFG with a locking plate. Materials and MethodsWe analyzed 26 consecutive patients with large tibial bone defects treated by free vascularized fibular graft (FVFG) and stabilization using a long locking plate between 2009 and 2018. All were followed up for a mean period of 42 months (24 to 120 months). Bony union, graft hypertrophy, and complications such as stress fracture and infections were assessed. Multivariate regression analysis was performed to identify any association between demographic factors, injury characteristics, treatment-related factors, and fibular hypertrophy. Additionally, The EQ-5D quality-of-life (QOL) indices were obtained using the SF-12 score to evaluate the patients' overall quality of life. ResultsThe mean age of the patients at the time of presentation was 36.26 yrs (range, 18–60 years). The cause of bone loss was open injury in 16 patients and infected nonunion in 10 patients. Complete union was achieved in 25 patients (96 %) without any requirement of additional surgical procedures. The mean union time of the graft was 4.04 months (range, 3–6 months). The mean fibular hypertrophy calculated by De Boer index was 0.61 %, 11 %, 28.24 % and 52.52 % at 3,6 months and 1 and 2 years respectively. Patients with metaphyseal bone loss have significant fibular hypertrophy. Participants in our study experienced a quality of life equivalent to 0.88 (range 0.79–0.99) of perfect health. ConclusionsFVFG with skin paddle and LCP fixation for massive tibial bone loss achieved satisfactory outcome and QALY even in the challenging healthcare environment of South India, a developing country.It maintains alignment, promotes graft hypertrophy, and prevents stress fractures. Level of evidenceLevel 4 Level of clinical careLevel I Tertiary trauma centre

Acute shortening and double-level lengthening versus bone transport for the management of large tibial bone defects after trauma and infection.

The aim of this study was to present our experience with a new modified Ilizarov technique of acute shortening and double-level lengthening (ASDL) for the management of large tibial bone defects after trauma and infection and compare it with bone transport (BT). A retrospective comparative study was performed on 47 patients with large tibial defects after trauma and infection from June 2014 to June 2018. Depending on different Ilizarov methods, these patients were divided into ASDL group (n=21) and BT group (n=26). The difference in bone lengthening time, time in frame, external fixation index, docking site healing time were recorded and compared between the two groups. Bone and functional results were evaluated according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria. Complications encountered in both groups were categorized according to the classification of Paley, including problems (treated nonoperatively), obstacles (treated operatively), and sequelae (unresolved at last). All patients were followed for at least two years since the lengthening frame was removed. All cases achieved complete union at the docking site and consolidation of the regenerate callus. The mean bone loss was 8.9cm (range 6.5-16.0cm) in ASDL group vs. 10.3cm (range 5.2-18.5cm) in BT group. The mean bone lengthening time was 2.4±0.7 months in ASDL group vs. 4.1±1.4 months in BT group (p<0.001); time in frame was 9.1 months (range 7.0-14.5 months) in ASDL group vs. 17.7 months (range 13.5-23.0 months) in BT group (p<0.001); and external fixation index was 1.04 months/cm (range 0.83-1.38 months/cm) in ASDL group vs. 1.91 months/cm (range 1.28-2.70 months/cm) in BT group (p<0.001). The incidence of obstacles occurred in ASDL group was significantly lower than that in BT group (p<0.001). There was no significant difference in the bone (p=0.635) and functional results (p=0.293) between the two groups. Compared with bone transport, our modified technique of acute shortening and double-level lengthening could reduce bone lengthening time, time in frame, external fixation index and postoperative complications. It showed better clinical effects in patients with large tibial bone defects after trauma and infection.

A Combination of Ilizarov Frame, Externalized Locking Plate and Tibia Bridging for an Adult with Large Tibial Defect and Severe Varus Deformity Due to Chronic Osteomyelitis in Childhood: A Case Report

Background: Various techniques have been reported to treat large, segmental tibial defects, such as autogenous bone graft, vascularized free fibula transfer and bone transport. We present a case of a 24-year-old male with a 17-year history of chronic osteomyelitis with obvious lower limb length discrepancy and severe varus deformity of the tibia secondary to osteomyelitis in childhood. Aim: The aim of this work is to provide an alternative choice for treating patients in developing countries with severe lower limb deformity caused by chronic osteomyelitis. Case Presentations: Without surgical intervention for a prolonged period of time, the patient was admitted in our institute for corrective surgery. Corrective surgery consisted of three stages: lengthening with Ilizarov frame, removal of Ilizarov frame and fixation with externalized locking plate, and removal of externalized locking plate. Tibia bridging was achieved at the distal and proximal junction. The range of motion (ROM) of the knee joint was nearly normal, but the stiffness of the ankle joint was noticeable. The remaining leg discrepancy of 0.1 cm required no application of a shoe lift. Moreover, the patient could engage in daily activities without noted limping. Conclusions: Distraction-compression osteogenesis using the Ilizarov apparatus is a powerful tool to lengthen the shortened long bone and adjust the deformity of the lower limbs. Externalized locking plates provide an alternative to the traditional bulky external fixator, as its low profile makes it more acceptable to patients without compromising axial and torsional stiffness. In all, a combination of Ilizarov frame, externalized locking plate and tibia bridging is an alternative for patients in similar conditions.

Application of 3D printed patient-specific instruments in the treatment of large tibial bone defects by the Ilizarov technique of distraction osteogenesis.

The Ilizarov technique of distraction osteogenesis is an effective treatment for tibia defect. However, repeated attempts to reduce due to the complexity of the bone defect during the operation will increase the operation time and iatrogenic injury, and excessive radiation exposure. Three-dimensional (3D)-printed patient-specific instrument (PSI) for preoperative 3D planning and intraoperative navigation have the advantages of accuracy and visualization. The purpose of this study is to investigate whether 3D-printed PSI is helpful to correct tibial bone defects accurately and effectively. From May 2019 to September 2022, 19 patients with tibial bone defects were treated, including 9 males and 10 females, aged 37 to 64 years. There were 4 cases in proximal tibia, 9 in midshaft tibia and 6 in distal tibia. All were treated with Ilizarov technique of distraction osteogenesis. 3D-printed PSI was used in 9 cases, while traditional surgery was used in 10 cases. All patients underwent computed tomography before surgery. Computer software was used to analyze the measurement results, design and print PSI. During the operation, PSI was used to assist in reduction of tibia. Operation times were recorded in all cases, the number of fluoroscopy during the operation, and the varus/valgus, anteversion/reversion angle after the operation were measured. All measurement data were expressed by means ± SD, and Student's t test was used to examine differences between groups. The chi square test or Fisher's precise test was used to compare the counting data of the two groups. All PSI matched well with the corresponding tibia bone defect, and were consistent with the preoperative plan and intraoperative operation. The affected limb had a good reduction effect. The operation time from the beginning of PSI installation to the completion of Ilizarov ring fixator installation was 31.33 ± 3.20 min, while that in the traditional operation group was 64.10 ± 6.14 min (p < 0.001). The times of fluoroscopy in the PSI group during operation was 10.11 ± 1.83, and that in the traditional operation group was 27.60 ± 5.82. The reduction effect of tibia in PSI group was better than that in traditional operation group, with the average angle of PSI group is 1.21 ± 0.24°, and that of traditional operation group is 2.36 ± 0.33° (p < 0.001). The PSI simplifies procedures, reduces the difficulty of the operation, improves the accuracy of the operation, and provides a good initial position when used in distraction osteogenesis to treat the tibial defects.

Use of Three-Column Reconstruction and Free Vascularized Fibular Grafts for the Repair of Large Tibial Defects after Tumor Resection.

This study aimed to evaluate the clinical outcomes of three-column reconstruction of the lower leg using a single-barrel contralateral vascularized fibular graft (VFG), medial locking plate, and the ipsilateral fibula for the repair of large tibial defects after tumor resection. In this retrospective study, we reviewed 12 patients who underwent three-column reconstruction using a single-barrel contralateral VFG, medial locking plate, and the ipsilateral fibula between June 1996 and May 2020. These patients had large tibial bone defects following tumor resection. The mean age of the patients was 26.3 years (range, 11-63 years), and 7 of them were women. The mean follow-up period was 104.8 months (range, 26-284 months). The mean size of the tibial bone defect after tumor resection was 17.8 cm (range, 11-26.8 cm). The clinical and radiological outcomes were evaluated at the final follow-up. All patients survived beyond the final follow-up without recurrence of the primary bone tumor. The mean time from reconstruction to bony union at both host-graft junctions was 12.9 months (range, 4-36 months). The mean Musculoskeletal Tumor Society score was 82.3% (range, 60%-97%). All tibial defects were reconstructed with adequate bone healing. There were 4 cases of stress fracture and graft failure; these were resolved by using longer plates and more screws. All patients were ambulatory without assistance and showed no permanent complications. Large tibial defects that occur after tumoral resection can be effectively reconstructed by three-column reconstruction using a medial locking plate, an inlay single-barrel VFG harvested from the contralateral side, and the intact ipsilateral fibula. This technique permits early weight-bearing before fibular hypertrophy and bony union.

Ilizarov Bone Transfer for Treatment of Large Tibial Bone Defects: Clinical Results and Management of Complications

The purpose of this study is to present our clinical experience using the Ilizarov bone transfer technique and free-flap technique in the reconstruction of large tibial bone and soft tissue defects, including an evaluation of both the management of postoperative complications and long-term outcomes. From January 2010 to May 2020, 72 patients with tibia bone and soft tissue defects were retrospectively evaluated. Either an anterolateral thigh perforator flaps (ALTP) or latissimus dorsi musculocutaneous flaps (LD), solely or in combination, were used to cover soft tissue defects. Once the flap was stabilized, an Ilizarov external fixator was applied to the limb. Follow-up was postoperatively performed at 1, 3, 6, 9, and 12 months. Postoperatively, there were two cases of total and five of partial flap necrosis, and two cases of subcutaneous ulcers, which were caused by vascular crisis, infection, and hematoma, respectively. All the patients underwent Ilizarov external fixator surgery after flap recovery. A total of 16 complications occurred, including 3 cases of simple needle tract infection (antibiotic treatment) and 13 cases of complications requiring reoperation. A correlation factor analysis revealed that the main factors affecting the healing time were the defect length and operative complications. All patients with complications treated with the vascularized iliac flap eventually healed completely. The Ilizarov method used together with an ALTP, LD, or a combination thereof yields good clinical results for repairing large bone and soft tissue defects of the tibia, thus reducing the incidence of amputations. However, longer treatment times may be involved, and postoperative complications can occur. The vascularized iliac flap may be a suitable choice for the treatment of postoperative complications of this type of Ilizarov bone transport.

Acute shortening and re-lengthening versus antibiotic calcium sulfate-loaded bone transport for the management of large segmental tibial defects after trauma

BackgroundThe purpose of this paper was to compare the clinical effects of acute shortening and re-lengthening (ASR) technique with antibiotic calcium sulfate-loaded bone transport (ACSBT) technique for the management of large segmental tibial defects after trauma.MethodsIn this retrospective study, 68 patients with large segmental tibial defects were included and completely followed. The bone loss was 3–10 cm. ASR group included 32 patients, while ACSBT group contained 36. There was no significant difference in demographic information between the two groups. The external fixation time (EFT) and external fixation index (EFI) were compared. Bone defect healing and limb functions were evaluated according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria. Complications were compared by Paley classification.ResultsThe mean EFT was 9.2 ± 1.8 months in ASR group and 10.1 ± 2.0 months in ACSBT group, respectively. The mean EFI was 1.5 ± 0.2 month/cm and 1.4 ± 0.3 month/cm. According to the ASAMI criteria, in ASR group bone defect healing was excellent in 22 cases, good in 7 cases and fair in 3 cases. In ACSBT group, it was excellent in 23 cases, good in 11 cases and fair in 2 cases. In ASR group, the limb function was excellent in 15 cases, good in 7 cases and fair in 10 cases, while it was excellent in 14 cases, good in 9 cases and fair in 13 cases with ACSBT group. There was no significant difference in EFI, bone defect healing and limb functions between the two groups (p > 0.05). The mean number of complications per patient in ACSBT group was significantly lower than that in ASR group (p < 0.05).ConclusionBoth techniques can be successfully used for the management of large segmental tibial defects after trauma. There was no significant difference in EFI, limb functions and bone defect healing between the two groups. Compared with ASR group, the complication incidence in ACSBT group was lower, especially the infection-related complications. Therefore, for patients with large segmental bone defects caused by infection or osteomyelitis, ACSBT technique could be the first choice.

Evaluation of the efficacy of ipsilateral fibular transfer for reconstruction of large tibial defects in children: a retrospective study

BackgroundReconstruction of large tibial defects is often a major challenge in limb salvage. This study aimed to evaluate initial follow-up results of ipsilateral fibula transfer for the treatment of large tibial defects in children.MethodsA retrospective study was performed between September 2014 and April 2021. Ten children were identified as having large tibial defects. The children underwent ipsilateral fibula transfer. We then evaluated initial healing, tibial length discrepancy, ankle varus/valgus, fibular position, refracture, infection, and function.ResultsFive boys and five girls, with an average age of 7.2 years, were evaluated. The transferred fibula was united in the patients. The mean follow-up period after fibular transposition was 43 months. The patients achieved primary bone union; the mean time to union was 8.4 months (range, 4–18 months). Complications included refracture (30%), infection (40%), tibia malunion (30%), ankle varus (30%), sensory loss of toes (10%), and ankle valgus (10%). No other major complications were observed. All 10 patients were able to perform activities of daily living and return to their normal activities.ConclusionIpsilateral fibula transfer is a salvage surgery for the treatment of large tibial defects in children with congenital pseudoarthrosis of the tibia, traumatic nonunion of the tibia, and/or tibial defect after chronic osteomyelitis. However, long-term results still need to be followed up.

40 years of microvascular reconstruction with latissimus dorsi muscle free flap

Introduction: The first use of the latissimus dorsi as a myocutaneous flap was described as early as the end of the 19th century, in the coverage of an extensive defect following radical mastectomy (Tansini 1895). Subsequently, the surgical procedure was forgotten and later re-introduced as a pedicled flap for breast reconstruction (Olivari 1976). Olivari prompted the microsurgical team from Ljubljana to perform a free muscle transfer (Godina 1978). The first emergency free flap transfer in Ljubljana was performed in 1979.Patients and Methods: Latissimus dorsi flap can be used as a muscle or musculocutaneous flap, in a pedicle or a free form. The procedure of reconstructing large tibial defects always proceeded as a two-team procedure simultaneously. For the continuity of the axial blood flow of the tibia, M. Godina developed end-to-side anastomosis.Results: Using latissimus dorsi free flap for reconstruction of tibial defects the first statistics by M. Godina from 134 patients showed a 0.75% flap loss rate and 1.5% infection rate; an average healing time of 6.8 months and a bed rest period estimated at 27 days. In the case of delayed reconstruction, the author reported an infection rate of 17.5%.Conclusions: Due to clinical experience, good results and a new doctrine of the Ljubljana School of microsurgery played a historical role in the reconstruction of the tibia with a muscular microvascular muscle flap.

Antibiotic calcium sulfate-loaded hybrid transport versus traditional Ilizarov bone transport in the treatment of large tibial defects after trauma

BackgroundThe purpose of this study was to compare the clinical effects of antibiotic calcium sulfate-loaded hybrid transport (ACSLHT) and traditional Ilizarov bone transport (TIBT) in the treatment of large tibial defects after trauma.MethodsEighty-five patients with large tibial defects after trauma were selected for retrospective study. The range of tibial defects was 6–22 cm. After thorough debridement and infection controlled, bone transport technique was used to reconstruct tibial defects. Forty-four patients were treated with ACSLHT technique (the ACSLHT group), while the other 41 were treated with TIBT technique (the TIBT group). Time in external fixator was evaluated by EFI score. Enneking score was used to evaluate limb functions. SAS score was used to evaluate postoperative anxiety status. In addition, complication incidence was compared, including axis deviation, docking site nonunion, infection recurrence and so on.ResultsThere was no significant difference in preoperative general data between ACSLHT and TIBT group. EFI score in ACSLHT and TIBT group was 0.6 ± 0.1 cm/month and 1.7 ± 0.3 cm/month, respectively (P < 0.05). Enneking score of ACSLHT and TIBT group was 86.5% and 75.1% (P < 0.05). SAS score of ACSLHT group was significantly lower than that of TIBT group (P < 0.05). Complication incidence in ACSLHT group was significantly lower than that in TIBT group (P < 0.05).ConclusionsCompared with TIBT group, ACSLHT group had shorter time in external fixator, better limb functions, lower postoperative anxiety score and lower complication incidence which is worth of clinical promotion.

An alternative therapeutic strategy for infected large bone defect and massive soft-tissue loss of leg-is free flap reconstruction inevitable?

This study aims to report the clinical and radiographic outcomes of a non-flap therapeutic strategy for the limb salvage of infected composite bone and soft-tissue defects of aleg, attempting to describe some new techniques regards the docking of bone ends. Twelve patients with infected large tibial bone defect (mean size 12.1 ± 2.8cm) and massive soft-tissue loss (mean size 254.5 ± 60.2 cm2) who were treated with the non-flap therapeutic strategy between 2014 and 2019 were retrospectively reviewed. Clinical and radiographic results were evaluated and analyzed. The results of bone and function were assessed by the Paley criteria. The exercise capacity of patients was evaluated based on the following four aspects: walking, running, jumping, squatting, and going up/down the stairs. During the treatment, shortening and re-lengthening technique was applied in six patients, bone transport technique in 12, submarine technique (SMT) in six, balloon dilatation technique (BDT) in seven, and soft-tissue incarceration creating technique (SICT) in seven. The mean external fixation time (EFT) and external fixation index (EFI) were 675.6 ± 179.2days (range, 366-1040days) and 60.1 ± 13.9days/cm (range, 47.0-95.5days/cm), respectively. Soft-tissue defect was successfully repaired for all patients. After a mean follow-up of 43.5 ± 23.2months (range, 13-103months), bone result was classified as "excellent" in ten patients, as "good" in one and "poor" in one, while functional result was graded as "excellent" in four patients and "good" in eight. The non-flap therapeutic strategy could be cautiously considered as an alternative treatment for the large lower limb composite defects.

Resveratrol and Angiogenin-2 Combined With PEGDA/TCS Hydrogel for the Targeted Therapy of Hypoxic Bone Defects via Activation of the Autophagy Pathway.

The guarantee of cell survival under hypoxic conditions and rapid vascularization is a key in tissue engineering strategies for treating bone defects. Our study aimed to establish the protective role of bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) in hypoxic conditions and realize rapid vascularization in bone defects. Resveratrol (Res), a non-flavonoid polyphenolic compound, and angiopoietin-2 (ANG2), a vascular activating factor, were applied to enhance BMSC and HUVEC survival, osteogenesis, and angiogenesis. The morphology, autophagy, viability, apoptosis, cycle, and osteogenic differentiation of BMSCs treated with Res were analyzed. The results indicated that Res could improve BMSC survival and differentiation via the autophagy pathway under hypoxic conditions. In addition, Res maintained HUVEC growth and proliferation in a hypoxic and ANG2 double-adverse environment via the autophagy pathway. To simulate a relatively hypoxic environment, small-aperture PEGDA/TCS hydrogels containing Res and ANG2 were prepared. BMSCs were cultured in the PEGDA/TCS scaffold and transplanted into a large tibial defect. CD31 immunofluorescence showed that the density and size of new blood vessels in the bone defect were significantly enhanced by ANG2 and Res at 8 weeks after surgery. H&E, Masson, and immunohistochemical staining results indicated that ANG2 combined with Res could promote new bone formation in defects. All these results suggested that Res combined with ANG2 may be a novel strategy for the targeted therapy of hypoxic bone defects with tissue engineering scaffolds.

Total flavonoids of rhizoma drynariae ameliorates bone formation and mineralization in BMP-Smad signaling pathway induced large tibial defect rats

Osteogenesis and angiogenesis acts as an essential role in repairing large tibial defects (LTDs). Total flavonoids of rhizoma drynariae (TFRD), a traditional Chinese medicinal herb, is reported to show anabolic effects on fracture healing. However, whether TFRD could improve the bone formation and angiogenesis in LTDs remains unknown. The purpose of this study was to evaluate the effect of TFRD on bone formation and angiogenesis in LTDs in distraction osteogenesis (DO). Using a previously established fracture model, LTD rats was established with circular external fixator (CEF). All rats then randomly divided into TFRD low dosage group (with DO), TFRD medium dosage group (with DO), TFRD high dosage group (with DO), model group (with DO) and blank group (without DO). Twelve weeks after treatment, according to X-ray and Micro-CT, TFRD groups (especially in medium dosage group) can significantly promote the formation of a large number of epiphyses and improve new bone mineralization compared with model group, and the results of HE and Masson staining and in vitro ALP level of BMSC also demonstrated the formation of bone matrix and mineralization in the TFRD groups. Also, angiographic imaging suggested that total flavonoids of TFRD was able to promote angiogenesis in the defect area. Consistently, TFRD significantly increased the levels of BMP-2, SMAD1, SMAD4, RUNX-2, OSX and VEGF in LTD rats based on ELISA and Real-Time PCR. In addition, we found that ALP activity of TFRD medium dosage group reached a peak after 10 days of induction through BMSC cell culture in vitro experiment. TFRD promoted bone formation in LTD through activation of BMP-Smad signaling pathway, which provides a promising new strategy for repairing bone defects in DO surgeries.

Morphological Changes in the Tibial Nerve During the Treatment of Large Tibia Defects Using Ilizarov Apparatus Combining with the Masquelet Technique: Experimental Study

Background. The use of Masquelet technology in combination with non-free osteoplasty according to Ilizarov in order to compensate large defects of the lower leg bones provides proper bone union and recurrence-free course of the disease, but the problem of patient rehabilitation remains relevant. The course and duration of the recovery period depend on the morphofunctional state of the tibial nerves. The purpose of this study was to determine morphological changes in the tibia nerve of dogs during the experimental treatment of large tibial defects using Ilizarov apparatus combining with the Masquelet technique. Materials and Methods. A defect of the upper third of the tibia in the form of false joint was created in 10 mongrel dogs. Then this defect was replaced with 25 mm diastasis, into which a cement spacer was placed. After 30 days, the latter was removed. At the level of the lower third, transverse osteotomy was performed, as well as distraction of 1 mm rate for 4 times per day, until complete contact of the fragments in the defect zone. The tibial nerves were studied within the periods of 60 days of fixation (F60) and 30 days after the fixator removal (FR30). Results. There were no mechanical damages of the nerves. During the experiment a part of epineural veins and arteries had obliterated lumens, two-fold decrease in the numerical density of endoneural arterioles, venules and capillaries was observed in FR30 — 97.5±2.5 in 1 mm2 (normally — 182.0±22.0), that evidenced of microcirculatory disorders progressing towards the end of the experiment. Patterns of Wallerian degeneration were found along with typical damages to fibers during distraction osteosynthesis demyelination and axonal degeneration. In F60 the proportion of modified fibers was 7.7±1.5%, which was 4.8 times higher (р = 0.52×10-5) above normal, the numerical densities and dimensional characteristics of fibers decreased. At the end of the experiment, the proportion of modified conductors 2.3-fold exceeded the norm (p = 0.33×10-4) — 3.7±0.4%, the numerical density of fibers remained 10.2% below the norm (p = 0.0362), making up 17436±865, but the average axon diameter and thickness of myelin sheaths were restored. Conclusion. Microcirculatory dysfunction, axonal atrophy, demyelination, Wallerian degeneration of a part of myelin nerve fibers and a decrease in their number revealed in the tibial nerves during the treatment of large tibia defects using the Masquelet technique combining with Ilizarov non-free bone grafting indicated the need for the use of adequate neurometabolic pharmacotherapy and effective rehabilitation.

Lower-limb Flip-Flap: A simple reliable modification of adipofascial flap for extensive tibial crest cutaneous defect

IntroductionLarge cutaneous defects exposing the whole tibial crest are difficult to cover and are conventionally best treated with free flaps. This article describes a technical modification of the adipofascial flap in this indication. MethodsThe “flip-flap” is vascularized by the posterior tibial artery perforators harvested on the medial aspect of the leg. The hypodermal and fascial tissue is de-epidermized and elevated from the posterior midline up to the medial edge of the soleus muscle, then folded over the exposed tibial crest like a page of a book. ResultsA 27×6cm effect was successfully covered on a 72 year-old patient with vascular status precluding free flap. The flap healed by day 21. Discussion/conclusionThis technical modification is simple and allows coverage of large tibial crest skin defect when a free flap is not possible.

Bifocal or Trifocal (Double-Level) Bone Transport Using Unilateral Rail System in the Treatment of Large Tibial Defects Caused by Infection: A Retrospective Study.

ObjectiveThe aim of this study is to assess the clinical results of bifocal or trifocal bone transport using unilateral rail system in the treatment of large tibial defects caused by infection.MethodsThere were a total of 37 eligible patients with an average age of 40.11 ± 10.32 years (range, 18–57 years; 28 males and nine females) with large tibial defects due to infection who were admitted to our hospital from June 2006 to June 2016. Among the patients, 21 underwent bifocal bone transport (BF group), and the remaining 16 were treated with trifocal bone transport (TF group). The demographic data (age, sex, interval duration before bone transport, previous operation time), intraoperative outcomes (size and location of the defect, size of soft tissue defect), postoperative variables (lengthening speed, external fixation index, duration of regenerate consolidation and docking union), postoperative bone and functional outcomes evaluated by Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system, and postoperative complications evaluated by Paley classification (muscle contraction, axial deviation, delayed consolidation, pin problems, repeated fracture, joint stiffness and others) of the two groups were recorded and compared at a minimum follow‐up of 24 months.ResultsThe mean duration of follow‐up after removal of fixator was 29.49 ± 4.34 months (range, 24–38 months). There was no statistically significant difference in the demographic data, intraoperative outcomes including size and location of the defect, size of soft tissue defect, as well as postoperative complications. However, postoperative functional result in the TF group were superior to those in the BF group at a minimum follow‐up of 24 months, and lengthening speed, external fixation index (EFI), duration of regenerate consolidation and docking union were significantly reduced in the TF group when compared with the BF group.ConclusionsTreatment of large tibial defects caused by infection with trifocal bone transport using unilateral rail system could significantly improve postoperative functional recovery and reduce duration of regenerate consolidation and docking union. The present study provides novel insight for the treatment of large tibial defects caused by infection.