Tibial Bone Defects Research Articles

Osteogenic potential of esculetin-loaded chitosan nanoparticles in microporous alginate/polyvinyl alcohol scaffolds for bone tissue engineering.

Bone tissue engineering (BTE) is an emerging strategy for the treatment of critical bone defects using biomaterials and cells. Esculetin (ES), a coumarin phytocompound, has demonstrated therapeutic potential, although its osteogenic effects remain insufficiently explored. Owing to its hydrophobic nature, which limits its bioavailability, this study developed a drug delivery system using chitosan nanoparticles (nCS) to achieve sustained release of ES. These ES-loaded nCS nanoparticles were incorporated into biocomposite scaffolds composed of alginate (Alg) and polyvinyl alcohol (PVA) using freeze-drying. The synthesized nCS-ES nanoparticles exhibited spherical morphology with a uniform size distribution, ranging from 105 to 117nm, and demonstrated excellent entrapment efficiencies (94.07 to 97.61%). The nanoparticles displayed high zeta potential values (+27.8 to +33.2mV), ensuring stable dispersion. The biocomposite scaffolds exhibited a uniform distribution of pores, with pore diameters ranging from 106±14μm to 112±14μm. The biocomposite scaffolds exhibited excellent swelling, protein adsorption, biodegradation, and biomineralization properties. The ES-loaded scaffolds showed sustained ES release, promoting osteogenesis in vitro, with the activation of the Wnt/β-catenin signaling pathway. In vivo studies using a rat tibial bone defect model further confirmed that these scaffolds stimulated new bone formation, highlighting the ES's potential for BTE applications.

Application of 3D-printed porous prosthesis for the reconstruction of infectious bone defect with concomitant severe soft tissue lesion: a case series of 13 cases

Abstract Background Treating infectious bone defects combined with large soft-tissue lesions poses significant clinical challenges. Herein, we introduced a modified two-stage treatment approach involving the implantation of 3D-printed prostheses and flap repair to treat large segmental infectious tibial bone defects. Method We conducted a retrospective study of 13 patients treated at our center between April 2018 and March 2022 for tibial infections owing to posttraumatic infection and chronic osteomyelitis combined with soft tissue defects. The average defect length was 14.0 cm (range, 5.7–22.9 cm). The flap area ranged from 14 × 5 to 15 × 8 + 25 × 15 cm. Sural neurocutaneous, lesser saphenous neurocutaneous, and local fasciocutaneous flaps were used to repair the skin defects. In the second stage, 3D-printed prostheses were designed and implanted. Union rate, complications, and functional outcomes were assessed at the final follow-up. Result The average follow-up period was 31.1 months (range, 17–47 months), with an average interval of 208.1 days (range, 139–359 days) between the two stages. According to our criteria, 7 of the 13 patients achieved radiographic healing without intervention. Two patients developed prosthesis-related complications and underwent revision surgery. Two patients experienced recurrent infections leading to prosthesis removal and debridement surgery, with the infection ultimately eradicated in one and the other undergoing amputation. Three patients experienced noninfectious flap-related complications, however, all eventually healed through surgical intervention. Conclusion The use of 3D-printed porous titanium prostheses combined with flap soft-tissue repair for the treatment of infectious tibial bone defects did not increase the rate of infection recurrence and provided good functional recovery, offering more options for the treatment of infectious bone defects.

Сhanges in the donor site following bone-patellar tendon-bone graft harvesting with open or closed defects

Background. The patellar tendon is frequently used as a graft source for anterior cruciate ligament reconstruction. The search of the factors that enhance the healing process of the donor site may contribute to improved anatomical and functional outcomes. The aim of the study — to determine the features of the harvesting techniques for better donor site healing by examining postoperative changes in the patellar tendon following two different graft harvesting methods. Methods. This study examined the condition of the patellar tendon after two methods of graft harvesting under the same early mobilization protocols. Group 1 (retrospective) enrolled 30 patients who underwent follow-up MRI at different times after surgery, during which ligamentous and bony defects were not closed. Group 2 (prospective) included 30 patients who received full-layer suturing of the patellar tendon and patellar and tibial bone defects plasty. Postoperatively, all patients underwent radiography and the Insall-Salvati ratio of their patellar position was evaluated. In Group 2, MRI was performed preoperatively and 12 months post-surgery, while CT scans were taken 1 day and 6 months post-surgery. MRI was utilized to measure the size and qualitatively assess the condition of the tendon, whereas bone defects were evaluated on CT scans. Results. The Insall-Salvati ratio of patellar position was within the physiological norm and did not differ between the groups (M1 = 1.11; SD1 = 0.13 and M2 = 1.12; SD2 = 0.15; p = 0.955). In Group 2, after 12 months, the length of the tendon was 3.1% shorter (M = -1.4 mm; SD = 2.4 mm; p = 0.003). The width of the tendon in the upper third and middle third was slightly increased (M = 0.3 mm; SD = 2.4 mm; p = 0.502 and M = 0.5 mm; SD = 2.1 mm; p = 0.205), while in the lower third it was 2.7% larger (M = 0.7 mm; SD = 1.7 mm; p = 0.034). The thickness of the tendon increased by 55% (M = 2.4 mm; SD = 1.6 mm; p = 0.001). All patients in Group 1 exhibited persistent bony and ligamentous defects. In Group 2, six months after surgery, cancellous bone filled the defects and integrated with the bone bed; 12 months later, the tendon was healed, and its shape and size approximated preoperative parameters. Conclusion. Full-layer suturing of the patellar tendon, reconstruction of defects using cancellous bone autograft, and early mobilization promote the healing of bone defects and restore the integrity, shape, and size of the tendon.

Strontium-Substituted Nanohydroxyapatite Containing Biodegradable 3D Printed Composite Scaffolds for Bone Regeneration.

Treatment of large-size bone defects is difficult, and acquiring autografts may be challenging due to limited availability. A synthetic patient-specific bone substitute can be developed by using 3D printing technologies in such cases. In the present study, we have developed photocurable composite resins with poly(trimethylene carbonate) (PTMC) containing a high percentage of biodegradable bioactive strontium-substituted nanohydroxyapatite (SrHA, size 30-70 nm). These photocurable resins have then been employed to develop high-surface-area 3D-printed bone substitutes using the digital light processing (DLP) technique. To enhance the surface area of the 3D-printed substitute, cryogels alone and functionalized with bioactive components of bone morphogenetic protein (BMP) and zoledronic acid (ZA) were filled within the 3D-printed scaffold/substitute. The scaffolds were tested in vitro for biocompatibility and functionality in vivo in two therapeutically relevant rat models with large bone defects (4 mm). The porosities of 3D printed scaffolds were found to be 60.1 ± 0.9%, 72.9 ± 0.5%, and 74.3 ± 1.6% for PTMC, PTMC-HA, and PTMC-SrHA, respectively, which is in the range of cancellous bone (50-95%). The thermogravimetric analysis demonstrated the fabrication of 3D printed composites with HA and SrHA concentrations of 51.5 and 57.4 wt %, respectively, in the PTMC matrix. The tensile Young's modulus (E), compressive moduli, and wettability increased post incorporation of SrHA and HA in the PTMC matrix. In vitro and in vivo results revealed that SrHA integrated into the PTMC matrix exhibited good physicochemical and biological properties. Furthermore, the osteoactive molecule-functionalized 3D printed composite scaffolds were found to have an adequate osteoconductive and osteoinductive surface that has shown increased bone regeneration and defect repair in both tibial and cranial bone defects. Our findings thus support the use of PTMC-SrHA composites as next-generation patient-specific synthetic bioactive biodegradable bone substitutes.

Early Postoperative Weight Bearing Following the Reconstruction of Traumatic Complex Tibial Bone Defects by Vascularized Free Fibula and Ilizarov External Fixator: A Case Series.

Post-traumatic tibial bone defects represent a significant challenge to orthopedic surgeons. Various reconstructive methods are available based on associated local soft tissue injury and defect size. Free vascularized fibular graft represents a major successful technique; combined with a rigid Ilizarov external fixator, it allows safe, immediate postoperative weight bearing. In this article, we describe a series of six patients managed according to the previously presented plan, achieving satisfactory results. A series of six patients, all males with an average age of 33.3 years, underwent reconstruction for post-traumatic complex tibial bony defects using contralateral free vascularized fibular grafts and Ilizarov external fixation. Initially, all patients underwent multiple sessions of debridement and a simple pin-to-bar external fixator. The bony defect averaged 15 cm, and the average harvested length of the fibula used for reconstruction was 22.1 cm. All patients started immediate total weight bearing postoperatively, with a mean time of 17 days after bony union Ilizarov was replaced with minimally invasive plate osteosynthesis (MIPO) in all patients, and continued full weight bearing (FWB). During the follow-up period, averaging 19.3 months, all patients achieved bony union with a mean time of 3.75 months. Patients spent an average of 6.4 months in the Ilizarov frame before it was replaced with MIPO; graft hypertrophy occurred in all patients, averaging 52.6%. The combined use of a vascularized fibular bone graft and an Ilizarov frame proves to be a successful and safe approach for immediate postoperative FWB. This yields comparable outcomes in terms of union and function.

Biomechanical analysis of different techniques for residual bone defect from tibial plateau bone cyst in total knee arthroplasty.

In patients with tibial plateau bone cysts undergoing total knee arthroplasty (TKA), bone defects commonly occur following tibial plateau resection. Current strategies for addressing these defects include bone grafting, bone cement filling, and the cement-screw technique. However, there remains no consensus on the optimal approach to achieve the best surgical outcomes. This study aims to evaluate the most effective repair method for residual bone defects following tibial plateau bone cyst repair during TKA from a biomechanical perspective. The treatment options for tibial plateau bone defects were classified into four categories: no treatment, cancellous bone filling, bone cement filling, and the cement-screw technique. Finite-element analysis (FEA) was employed to evaluate stress distribution and displacement across the models for each treatment group. In addition, static compression mechanical tests were used to assess the displacement of the models within each group. FEA results indicate that when employing the cement-screw technique to repair tibial plateau bone defects, the maximum stress on the prosthesis and the cement below the prosthesis is minimized, while the maximum stress on the cancellous bone is maximized. And the displacement of each component is minimized. Biomechanical tests results further demonstrate that the displacement of the model is minimized when utilizing the cement-screw technique for tibial plateau bone defects. Using cement-screw technique in treating residual tibial bone defects due to bone cysts in TKA offers optimal biomechanical advantages.

Consolidation of the Anteromedial Aspect of the Tibia is Inferior to The Other Areas in the Reconstruction of Critical-Sized Bone Defect of the Tibial Shaft using the Induced Membrane Technique: An Analysis of 111 Serial Computed Tomography of 37 patients.

To compare the consolidation quality between the anteromedial aspect of regenerated bone (AMRB) and other areas of regenerated bone (TORB) following the induced membrane technique (IMT) for managing critical-sized tibial shaft bone defects, and determine the factors affecting consolidation quality in the AMRB. Design: Retrospective comparative study. Academic Level I trauma center. Included were patients who underwent IMT with only an intramedullary nail for tibial shaft segmental defects and serial computed tomography immediately, 6 months, and 1 year postoperatively.Outcome Measures and Comparisons: Comparison were made of regenerative bone volume, density, and corticalization between AMRB and TORB. This study enrolled 37 patients with a mean age of 47.7 years (range 20-79). Twenty-eight (75.7%) patients were male. Postoperatively, the AMRB exhibited significantly more negative volumetric change than TORB at 0-1 year (-20.01% ± 25.59% vs. -13.32% ± 22.48%, p = 0.028), less positive density change 0-6 months (+197.84 ± 107.95 vs. +290.14 ± 131.74 HU, p < 0.001) and 0-1 year (+377.51 ± 150.71 HU vs. +455.48 ± 135.04 HU, p < 0.001), and lower corticalization rate in 1 year (49.77% ± 29.42% vs. 82.27 ± 19.73%, p < 0.001). Significant factors included fracture-related infection (FRI) (p = 0.047 and p = 0.048 at 0-6 months and 0-1 year, respectively) and longer defect length (p = 0.032 and p = 0.020) for the negative volumetric AMRB changes; older age (p = 0.004 and p = 0.016) for the AMRB negative density changes; higher percentage of mixed recombinant human bone morphogenetic protein-2 in graft material (p = 0.013 in 0-6 months) for the AMRB positive density change; FRI (p = 0.024) for the inferior corticalization rate of the AMRB; FRI (p = 0.026 in 0-1 year), longer defect length (p = 0.017 in 0-6 months), and higher mixed demineralized bone matrix (DBM) percentage (p = 0.010 in 0-1 year) for the difference in density change between the AMRB and TORB; higher mixed DBM percentage (p = 0.023) for the difference between the AMRB and TORB in corticalization rates. The tibial shaft's anteromedial aspects demonstrated significantly inferior consolidation after induced membrane technique, especially in terms of volume at 6 months, density at 6 months and 1 year, and corticalization at 1 year postoperatively. Therapeutic Level III.

Carboxymethyl chitosan-enhanced multi-level microstructured composite hydrogel scaffolds for bone defect repair

Critical-sized bone defects (CSBDs) necessitate interventions like bone grafts or tissue engineering scaffolds to surpass the body's limited spontaneous healing capacity and ensure effective bone regeneration. A multi-level microstructured composite hydrogel 3D scaffold was fabricated for enhanced bone defect repair, integrating a 3D-printed macroporous polylactic acid (PLA) scaffold with polydopamine treatment and filled with a sodium alginate/nano hydroxyapatite/carboxymethyl chitosan (SA/nHA/CMCS) micrometer-scale porous composite hydrogel. The incorporation of nano hydroxyapatite (nHA) nanoparticles enhanced hydrogel crosslinking and osteogenic activity. A systematic evaluation of CMCS concentration demonstrated its pivotal role in enhancing hydrogel cross-linking and mineralization, regulating degradation rate adapted to the osteogenic cycle, endowing the scaffold with a bioactive micrometer-scale porous structure. In vitro studies confirmed the osteogenic effectiveness of the composite hydrogel 3D scaffold, particularly those with CMCS, which boosted bone mesenchymal stem cells (BMSCs) adhesion, proliferation, and differentiation. The rabbit tibial bone defect model further confirmed that, compared to the DAPLA (dopamine modified PLA) scaffold, the bone trabecular number of the DSHC (DAPLA-SA/nHA/CMCS) scaffold increases 2.06-fold. In conclusion, this study expanded the application of hydrogel scaffolds in bone tissue engineering and provided an effective strategy for the development of hydrogel implant materials.

Main Surgical Methods of Critical Tibial Bone Defects Replacement (Literature Review). Part II

Summary. This part of literature review is devoted to the main methods of critical bone defects replacement of the tibia, which cannot be repaired by using bone autoplasty. A search in the PubMed database for the period 2010 - 2023 was carried out, with preference given to the material from the last 5 years; the advantages and disadvantages of the most popular methods of treatment are shown. This article provides a descriptive, non-systematic review of the current literature on methods of tibial bone defect replacement and possible directions for future research. A thorough search in the PubMed database was performed using relevant search terms, with peer-reviewed articles in English identified and evaluated. No strict inclusion or exclusion criteria were used to select articles for a full-text review. Instead, a subjective assessment of the relevance of individual articles to the overall narrative and surgical techniques review was made, which ultimately resulted in 40 articles being referenced.

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.

Clinical application of iliac myocutaneous flap pedicled with deep circumflex iliac artery in repair of complex defect of lower limb with cavity

To explore the effectiveness of iliac myocutaneous flap pedicled with deep circumflex iliac artery (DCIA) on the repair of lower limb composite defect wounds with cavity. A retrospective analysis of 7 patients with lower limb composite defect wounds treated between March 2017 and September 2020 was conducted, including 4 males and 3 females, aged 24-58 years, with a median age of 37 years. The causes of injury were machine twisting injury in 2 cases, fall from height injury in 2 cases, and traffic accident injury in 3 cases. According to Gustilo-Anderson classification, there were 1 case of type Ⅲa, 4 cases of type Ⅲb, and 2 cases of type Ⅲc (combined with anterior tibial artery rupture); according to AO/Orthopaedic Trauma Association (AO/OTA) classification, there were 2 cases of type 42-C3, 2 cases of type 43-A2, and 3 cases of type 43-B1. The time from injury to admission ranged from 2 to 10 hours, with an average of 6 hours. Tibial bone defect and surrounding soft tissue defect with deep cavity were left after primary emergency debridement. In the second stage, according to the characteristics of the wound, the three-dimensional repair of the composite defect was designed with DCIA embedded iliac myocutaneous flap. The size of the iliac flap was 2.0 cm×2.0 cm×2.0 cm to 7.0 cm×3.0 cm×2.5 cm, and the size of the flap was 12.0 cm×8.0 cm to 21.0 cm×13.0 cm. The internal oblique muscle flap was harvested in size of 3.0 cm×2.0 cm×2.0 cm to 5.5 cm×4.0 cm×4.0 cm. The donor site was primarily closed. All the flaps survived after operation, except for 1 case of partial necrosis of the flap edge, which healed after secondary skin grafting, and the donor and recipient wounds healed by first intention. All patients were followed up 16-24 months, with an average of 18 months. The broken end of the bone defect healed well, and the healing time was 8-10 months, with an average of 7.3 months. At last follow-up, the shape of the flap was satisfactory, the texture was soft, and there was no abnormal hair growth, pigmentation, and so on. Only linear scar was left in the donor site, and no complication such as abdominal hernia occurred. According to Paley fracture healing scoring system, bone healing was rated as excellent in 5 cases and good in 2 cases. The limb function was satisfactory, and full weight bearing was achieved at 12-16 months after operation. According to the lower extremity functional scale (LEFS), 6 cases were excellent and 1 case was good. The iliac myocutaneous flap pedicled with DCIA is flexible in design and highly free in tissue composition, which can repair the composite defect wound of lower limbs with deep cavity in a three-dimensional way, and repair the limb shape and reconstruct weight-bearing function to the greatest extent.

Long-term results and patient-reported outcomes after vascularized fibular graft use in the treatment of post-traumatic bone defects of femur shaft and tibia: A retrospective cohort and cross-sectional survey study

Post-traumatic critical-sized bone defects pose a reconstructive challenge for reconstructive surgeons. The vascularized fibula graft is a well-described treatment for osseous defects of the femur and tibia. This study aimed to assess long-term patient-reported quality of life, the success-, and complication rates in lower extremity reconstruction with vascularized fibula grafts. A retrospective cohort of 29 patients who underwent fibula graft reconstruction for critical-sized bone defects after post-traumatic tibial and femoral bone loss between 1990 and 2021 was included. To assess the health-related quality of life and return to work and satisfaction, a cross-sectional survey was performed using the short-form-36, lower extremity functional scale, and a self-made questionnaire including the DN4, satisfaction, and subjective ankle function. The median bone defect size was 8cm (IQR 9-7cm). The mental component scores were comparable to the Dutch population norm, whereas the impaired physical function scores were associated with pain (r 0.849, p<0.001). Neuropathic symptoms were reported in 7 out of 19 patients, and 11 out of 19 patients returned to normal daily activity. All respondents reported positive or neutral scores on overall satisfaction with the recovery. Bone healing was uneventful in 19 out of 29 patients. Union was achieved in 25 out of 29 patients. Persistent nonunion was observed in 4 patients, leading to amputation in 2 patients. Vascularized fibula graft use led to high union rates and limb salvage in patients with post-traumatic segmental bone loss of the tibia and femur. Patient satisfaction with the overall recovery was positive; however, functional outcomes remained impaired.

Comparative biochemical analysis of platelet-rich plasma-chitosan and platelet-rich fibrin-chitosan for treating tibial bone defects in rabbits.

Fracture healing can cause serious complications, both preoperatively and postoperatively, including malunion or non-union. Biomaterials can enhance the fracture healing process. This study aimed to compare platelet-rich plasma (PRP)-chitosan and platelet-rich fibrin (PRF)-chitosan on the basis of biochemical parameters for fracture treatment in rabbits. This study involved 12 clinically healthy rabbits. After preparing PRP and PRF, a 3-mm bone defect was created in the tibia of each rabbit. The animals were divided randomly into two groups (A and B). Group A received PRP-Chitosan, and Group B received PRF-Chitosan. Bone healing was assessed using biochemical parameters (calcium [Ca], phosphorus [P], serum alkaline phosphatase [ALP], and osteocalcin [Ocn]) at 2-, 4-, 6-, and 8-week postoperatively. The data were compared using repeated-measures analysis of variance (p < 0.05) with Statistical Package for the Social Sciences statistical software. Group-wise comparison showed no significant differences (p > 0.05) between the groups, except for ALP levels, which were significantly higher in Group B than in Group A (p < 0.05). In the week-wise comparison, there was a significant difference between both groups, as Ca and ALP levels showed significant differences at all weeks postoperatively, whereas Ocn showed a significant difference at 2- and 4-week postoperatively (p < 0.05). However, there was no difference in P levels between the groups at any post-operative week (p > 0.05). Both combinations enhanced bone regeneration. However, PRF-Chitosan is a better combination for bone repair than PRP-Chitosan. There were some limitations of this study, such as a small sample size, only male rabbits were used, and a lack of mechanical testing; these limitations should be addressed in future studies. The insights gained from the present study may open a new approach to the use of a combination of biomaterials for bone healing, which should be further investigated clinically and in other animal models as a future scope.

Application of the Modified RUST Score in Tibial Bone Transport and Factors Associated with Docking Site Complications.

Reconstruction of segmental bone defects with bone transport is a well-established treatment. Mechanical complications at the docking site after frame removal are common. These complications include malunion, non-union, axial deviation and refracture. A simple tool to assess the healing of the docking site is currently lacking. The aim of this study is to evaluate the use of the modified RUST (mRUST) score in the setting of bone transport and to identify factors associated with an increased risk of docking site complications. This retrospective study was conducted at a single tertiary centre in South Africa, included 24 patients with a tibial bone defect treated with bone transport and a circular frame between 2014 and 2023. Demographic data, clinical and bone transport characteristics were recorded. Mechanical complications, such as fracture, non-union, any angulation >5°, shortening >5 mm, or any other complication requiring reoperation, were recorded. The mRUST was adapted as a ratio for the purpose of this study to overcome the common occurrence of cortices being obscured by the frame. The mRUST ratio was applied before and after frame removal for each patient by three appraisers. Comparison between the groups with and without complications was performed regarding bone transport characteristics, docking site configuration and mRUST ratio. The correlation of the score between radiographs before and after frame removal was assessed. The inter-rater reliability of the mRUST was analysed using Fleiss Kappa statistics for each cortex individually and the intraclass correlation coefficient (ICC) for the mRUST ratio. In this study, 20 men and 4 women with a median age of 26 years were included. The overall rate of mechanical complications after frame removal was 21.7%. Complications were all related to the docking site, with two angulations, two fractures and one non-union. Demographics, bone transport characteristics and mRUST ratio before and after frame removal were similar between the two groups. Regarding the configuration of the docking site, an angle of 45° or more between the bone surfaces was associated with the occurrence of mechanical complications (p < 0.001). The correlation of the mean mRUST ratio before and after frame removal showed a moderate relationship, with a Spearman correlation coefficient of 0.50 (p-value 0.13). The inter-rater reliability of the mRUST was "fair" (kappa 0.21-0.40) for the scoring of individual cortices, except for one score which was "slight" (kappa 0.00-0.20). The ICC of the mRUST ratio was 0.662 on radiographs with the frame, and 0.759 after frame removal. This study did not find the mRUST or mRUST ratio useful in assessing the healing of the docking site to decide on the best time to remove the frame. However, a notable finding was that the shape and orientation of the bone ends meeting at the docking site might well be relevant to decrease complication rates. If the angle between the bony surfaces is 45° or more, it may be associated with an increased risk of complications. It may be worthwhile considering reshaping these bone ends at the time of debridement or formal docking procedure to be more collinear, in order to reduce the potential for mechanical complications such as non-union, axial deviation or refracture at the docking site. Kummer A, Nieuwoudt L, Marais LC. Application of the Modified RUST Score in Tibial Bone Transport and Factors Associated with Docking Site Complications. Strategies Trauma Limb Reconstr 2024;19(2):73-81.

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.

Bone Transport for Large Segmental Tibial Defects Using Taylor Spatial Frame versus the Ilizarov Circular Fixator.

Bone transport has become the gold standard for treating large segmental tibial bone defects. The technique for application the Ilizarov circular fixator (ICF) has a long learning curve and is associated with many complications. There are few clinical studies on bone transport via the Taylor spatial frame (TSF). The main purpose of this study was to compare the radiological and clinical and outcomes of bone transport by using the TSF and the ICF. There were 62 patients included in this retrospective study from June 2011 to June 2021 and distributed to two groups according to the fixation method: a TSF group consisting of 30 patients and an ICF group consisting of 32 patients. Demographic information, surgical duration, external fixation times, external fixation index, final radiographic results, complications, and clinical outcomes were recorded and examined. The clinical outcomes were assessed using the ASAMI criteria during the most recent clinical visit. Then, statistical analysis such as independent-samples t tests or chi-Square test was performed. The mean surgical duration in the TSF group was 93.8 ± 7.3 min, which was shorter than that in the ICF group (109.8 ± 1.4 min) (p < 0.05). Compared to the ICF group (10.2 ± 2.0 months), the TSF group (9.7 ± 1.8 months) had a shorter average external fixation time (p > 0.05). The external fixation index was 1.4 ± 0.2 m/cm and 1.5 ± 0.1 m/cm in the two groups. Moreover, there was no significant difference between the two groups. At the last follow-up visit, the medial proximal tibial angle (MPTA) and posterior proximal tibial angle (PPTA) in the TSF group were 88.1 ± 12.1° and 80.9 ± 1.3°, respectively. The MPTA and PPTA in the ICF group were 84.4 ± 2.4° and 76.2 ± 1.9°, respectively. There were statistically significant differences between the two groups (all p < 0.05). The complication rate was 50% in the TSF group and 75% in the ICF group. Moreover, the ASAMI score between the two groups was no statistically significant difference (p > 0.05). No statistically significant difference was found in clinical outcomes between the use of Taylor spatial frame and Ilizarov circular fixator for treating large segmental tibial bone defects. However, TSF is a shorter and simpler procedure that causes fewer complications and improves limb alignment.

"Is every revision the same?" definition of complexity in knee revision surgery.

The purpose of this paper is to define a subset of complex rTKA in terms of preoperative, intraoperative, and postoperative outcomes and complications. The secondary outcome of the authors is to propose a simple and easy-to-use guide for clinical network in rTKA management. Complex rTKAs were defined according to the presence of at least two of the following features: periprosthetic joint infection, re- revision, femoral and/or tibial massive bone defects, soft tissue impairment, stiffness, fracture requiring fixed component revision. Twenty-six patients underwent a standard rTKA (group A) while 24 had a complex rTKA (group B). The mean follow-up was 50.2 ± 16.4 months in group A and 49.5 ± 16.8 in group B (p = 0.44). The operative time was longer in group B (200.4 ± 131.4 min vs 110.2 ± 59.8 min). A greater intraoperative total blood loss (3014.2 ± 740.0 vs 2328.5 ± 620.6 ml, p < 0.001), intra and postoperative blood infusion (3.6 ± 1.2 vs 2.1 ± 1.2 units, p < 0.001) was reported in group B. Significant difference was obtained for global complication rate (11.5% group A vs 37.5% group B, p = 0.04), reoperation (7.7% group A vs 33.3% group B, p = p = 0.03) and re-revision (3.8% group A vs 25% group B, p = p = 0.04). This study describes a specific entity of rTKA that require higher surgical effort and increased surgical challenge (measured as increased surgical time, need of transfusions and complications). The proposed classification could provide an easy-to-use tool for quick grading of complexity in rTKA.

A Novel Method to Assess Healing of Segmental Bone Defects using the Induced Membrane Technique.

Clinical concerns exist regarding the quality of bony consolidation in the context of the induced membrane technique. This study evaluates the clinical process of bone grafting in the second stage of induced membrane bone union in patients with tibial bone defects to infer the possibility of non-union and establish a reliable and effective evaluation method combined with computed tomography (CT) to assess fracture healing. Patients with tibial bone defects who underwent the induced membrane technique at our hospital between February 2017 and February 2020 were retrospectively analyzed. The Hounsfield unit (HU) values of the patients were evaluated at different times during the second stage of bone grafting. Bone healing at the boundary value of the 120 HU output threshold (-1024 HU-3071 HU) was directionally selected, and the changes in the growth volume of union (new bone volume [selected according to HU value]/bone defect volume) were compared with analyzing individual class bone union. Method 1 involved X-rays revealing that at least three of the four cortices were continuous and at least 2 mm thick, with the patient being pain free. For Method 2, new bone volume (selected according to HU value/bone defect volume) at the stage was compared with analyzing individual class healing. Receiver operating characteristic curve analysis was used for Methods 1 and 2. A total of 42 patients with a segmental bone defect with a mean age of 40.5 years (40.5 ± 8.3 years) were included. The relationship between bone graft volume and time variation was analyzed by single factor repeated variable analysis (F = 6.477, p = 0.016). Further, curve regression analysis showed that the change in bone graft volume over time presented a logarithmic curve pattern (Y = 0.563 + 0.086 × ln(X), Ra2 = 0.608, p = 0.041). ROC curve analysis showed that Method 2 is superior to Method 1 (AUC: 86.3% vs. 68.3%, p < 0.05). The induced membrane technique could be used to treat traumatic long bone defects, with fewer complications and a higher healing rate. The proposed imaging grading of HU (new bone volume/bone defect volume) can be used as a reference for the quality of bony consolidation with the induced membrane technique.

Biomechanical Effects of Stem Extension of Tibial Components for Medial Tibial Bone Defects in Total Knee Arthroplasty: A Finite Element Study.

The aim of this study was to investigate the biomechanical effects of stem extension with a medial tibial bone defect in primary total knee arthroplasty (TKA) on load distribution and stress in the proximal tibia using finite element (FE) analysis.FE simulations were performed on the tibia bone to evaluate the stress and strain on the tibia bone and bone cement. This was done to investigate the stress shielding effect, stability of the tibia plate, and the biomechanical effects in TKA models with various medial defects and different stem length models.The results demonstrated that in the bone defect model, the longer the stem, the lower the average von Mises stress on the cortical and trabecular bones. In particular, as the bone defect increased, the average von Mises stress on cortical and trabecular bones increased. The average increase in stress according to the size of the bone defect was smaller in the long stem than in the short stem. The maximal principal strain on the trabecular bone occurred mainly at the contact point on the distal end of the stem of the tibial implant. When a short stem was applied, the maximal principal strain on the trabecular bone was approximately 8% and 20% smaller than when a long stem was applied or when no stem was applied, respectively.The findings suggest that a short stem extension of the tibial component could help achieve excellent biomechanical results when performing TKA with a medial tibial bone defect.

Main Surgical Methods of Critical Tibial Bone Defects Replacement (Literature Review)

Main Surgical Methods of Critical Tibial Bone Defects Replacement (Literature Review)