Tibial Reconstruction Research Articles

Endoprosthetic replacement with preservation of the epiphysis for proximal tibial reconstruction after osteosarcoma resection in children: a case report

BackgroundLimb salvage surgery is an important method for treating malignant tumors of the bone involving the adjacent parts of the major joints in children. This technique allows for preservation of limb function, especially in the lower limb. However, the reconstruction of the proximal end of the tibia after removing the tumor mass with a rational scale to preserve the total knee joint and reduce limb length discrepancy presents a challenge.Case presentationWe present a case of osteosarcoma of the proximal tibia. After being treated with an extended tumor resection, the proximal tibia of the child was restructured using endoprosthetic replacement with epiphyseal preservation. This procedure preserves the entire articular surface and growth plate of the knee joint of the affected limb and provides a feasible alternative protocol for retaining the function and growth potential of the affected limb. The patient remained disease-free and normal limb motor function was observed during the 3.5 year follow-up since the initial surgery.ConclusionsPreservation of the epiphysis enabled our patient to perform better limb function after limb-saving surgery as a result of his undamaged knee joint and minimized limb-length discrepancy. We believe that endoprosthetic replacement with preservation of the epiphysis can provide the best strategy for reconstruction after resection of focal malignant tumors in long bones without epiphytic involvement.

High Above Knee Amputations for Femoral Osteosarcomas Treated with Free Microsurgical Tibial Reconstruction in the Pediatric Population.

Improvements in the management of pediatric sarcoma including imaging, neo- and adjuvant therapy, and surgical technique has enhanced long-term survival of patients. Pediatric patients diagnosed with a femoral osteosarcoma undergoing oncologic resection who are ineligible for limb preservation reconstruction or rotationplasty are offered an above knee amputation (AKA). Limb amputations in the skeletally immature patient poses particular problems specific to endosteal bone overgrowth and spiking. Approximately half of these patients undergo revision of their amputation site. Furthermore, a high AKA often requires a hip-based prosthesis, which can be uncomfortable leading to poorer outcomes and higher energy expenditures.We have completed four 'spare parts' microvascular free tibial transfers for pediatric patients diagnosed with femoral osteosarcoma who were treated with an AKA. Two of these patients are currently ambulatory with their prosthetic and have not required long-term revision of their amputation site. One patient demonstrated radiographic evidence of bony union four months post-operatively, but subsequently succumbed to chemotherapy-resistant metastases. The fourth patient is in the process of prosthetic fitting and rehabilitation.This is a novel technique and the first series describing both proximal and distal free microvascular tibial bone transfers as a reconstructive option for pediatric patients with femoral osteosarcomas. It is a reliable flap with possible variations in vascular anatomy. Furthermore, it offers multiple benefits including the prevention of bony spiking, AKA stump augmentation, and facilitation of appropriate prosthetic fitting improving functional outcomes and decreased energy expenditure. However, the soft tissue coverage must be well planned.

3D printed CoCrMo personalised load-bearing meta-scaffold for critical size tibial reconstruction

Porous scaffolds have evolved, allowing personalised 3D-printed structures that can improve tissue reconstruction. By using scaffolds with specific porosity, Poisson's ratio and stiffness, load-bearing tissues such as tibial reconstruction can be improved. Recent studies suggest the potential for negative Poisson's ratio (−υ) meta-scaffolds in mimicking the behaviour of natural tissue, leading to improved healing and tissue reintegration. This study reveals a porous meta-scaffold that offers high −υ and can be personalised to match desired stiffness. By using laser powder bed fusion (L-PBF) of CoCrMo, a porous structure was created, characterised by its ability to achieve heightened −υ. Prototype testing and numerical modelling unveiled a proxy-model capable of predicting and personalising the porosity, yield strength, elastic modulus, and −υ of the tibial meta-scaffold representing a novel contribution to the field. The surrogate model also aids characterising the impact of design variables such as of the scaffold on the key performance requirements of the tibial scaffold. This approach enables the fabrication of porous biomaterials with personalised properties, specifically suited for load-bearing tibial reconstruction. The resulting meta-scaffold offers −υ ranging from -0.16 to -0.38, porosity between 73.46% and 85.36%, yield strength of 30–80 MPa, and elastic modulus ranging from 8.6 to 22.6 GPa. The optimised architecture feature −υ of 0.223 and a targeted elastic modulus of 17.53 GPa, while also showcasing yield strength and porosity of 57.2 MPa and 76.35%, respectively. By combining 3D printing with tailored scaffolds, this study opens doors to mass customisation of improved load-bearing porous biomaterials that of negative Poisson's ratio and stiffness matching.

A novel quantitative grading system for implant fixation in revision total knee arthroplasty.

Obtaining solid implant fixation is crucial in revision total knee arthroplasty (rTKA) to avoid aseptic loosening, a major reason for re-revision. This study aims to validate a novel grading system that quantifies implant fixation across three anatomical zones (epiphysis, metaphysis, diaphysis). Based on pre-, intra-, and postoperative assessments, the novel grading system allocates a quantitative score (0, 0.5, or 1 point) for the quality of fixation achieved in each anatomical zone. The criteria used by the algorithm to assign the score include the bone quality, the size of the bone defect, and the type of fixation used. A consecutive cohort of 245 patients undergoing rTKA from 2012 to 2018 were evaluated using the current novel scoring system and followed prospectively. In addition, 100 first-time revision cases were assessed radiologically from the original cohort and graded by three observers to evaluate the intra- and inter-rater reliability of the novel radiological grading system. At a mean follow-up of 90 months (64 to 130), only two out of 245 cases failed due to aseptic loosening. Intraoperative grading yielded mean scores of 1.87 (95% confidence interval (CI) 1.82 to 1.92) for the femur and 1.96 (95% CI 1.92 to 2.0) for the tibia. Only 3.7% of femoral and 1.7% of tibial reconstructions fell below the 1.5-point threshold, which included the two cases of aseptic loosening. Interobserver reliability for postoperative radiological grading was 0.97 for the femur and 0.85 for the tibia. A minimum score of 1.5 points for each skeletal segment appears to be a reasonable cut-off to define sufficient fixation in rTKA. There were no revisions for aseptic loosening at mid-term follow-up when this fixation threshold was achieved or exceeded. When assessing first-time revisions, this novel grading system has shown excellent intra- and interobserver reliability.

The use of vascularized fibula flap with allograft in post-oncologic microsurgical bone reconstruction of lower limbs in pediatric patients.

Post-oncologic surgical reconstruction of lower limbs in pediatrics remains a challenging topic. Microsurgical techniques allow reconstructions of large bony defects. The use of vascularized fibular flap with allograft has proven to be an ideal biologic construct. We aim to assess the success rate of this operation, including flap survival, bony union, weight-bearing ambulation, and complications in a long-term follow-up in our case series compared to the literature. Our case-series includes 18 femoral resections (9 osteosarcomas, 8 Ewing sarcoma, and 1 desmoid tumor) and 15 tibial resections (10 osteosarcoma, 4 Ewing sarcoma, and 1 Malignant Fibrous Histiocytoma). We collected patients' demographics, type of tumor, type of resection, defect size, fibula-flap length, method of fixation, anastomosis site, follow-up data, complications, and their management. All survivals were examined by X-ray and CT-scan to evaluate the morphological changes of the vascularized fibula and follow-up. The functional evaluation was performed by the 30-point Musculoskeletal Tumor Society Rating Score (MSTS) for the lower limb (Enneking et al., Clinical Orthopaedics and Related Research 1993(286):241-246). The mean age of the femur resection patients' group was 11.2 years with a mean defect size of 14 cm and a mean length of the fibular flap of 18 cm; for the tibia the mean age was 12 years with a mean defect size of 14 cm and a mean length of the fibular flap of 16.6 cm. The overall survival of the reconstructions at 5 years follow-up was 17 out 18 cases for the femur and 13 out of 15 cases for the tibia. MSTS score was 28.2 for the femur and 23.7 for the tibia. The average time of union of the fibula was seen after 5 months, while allograft consolidation was observed around 19.7 months. The mean time of follow-up was 144.5 months for the femur and 139.2 months for the tibia. The complication rate observed was 7 out of 18 for the femur and 7 out of 15 for the tibia reconstructions. The viability of the fibula is a cornerstone in the success of reconstruction as well as the successful management of complications in intercalary defects after tumor resection in pediatrics to restore good functionality. Our results are in line with those reported in the literature in terms of overall complication rates. The high primary union of allograft, the high MSTS score obtained, and the low rate of severe complications reflect the mechanical role of this reconstructive technique over a long follow-up.

Deep-learning based 3D reconstruction of lower limb bones from biplanar radiographs for preoperative osteotomy planning

PurposeThree-dimensional (3D) preoperative planning has become the gold standard for orthopedic surgeries, primarily relying on CT-reconstructed 3D models. However, in contrast to standing radiographs, a CT scan is not part of the standard protocol but is usually acquired for preoperative planning purposes only. Additionally, it is costly, exposes the patients to high doses of radiation and is acquired in a non-weight-bearing position.MethodsIn this study, we develop a deep-learning based pipeline to facilitate 3D preoperative planning for high tibial osteotomies, based on 3D models reconstructed from low-dose biplanar standing EOS radiographs. Using digitally reconstructed radiographs, we train networks to localize the clinically required landmarks, separate the two legs in the sagittal radiograph and finally reconstruct the 3D bone model. Finally, we evaluate the accuracy of the reconstructed 3D models for the particular application case of preoperative planning, with the aim of eliminating the need for a CT scan in specific cases, such as high tibial osteotomies.ResultsThe mean Dice coefficients for the tibial reconstructions were 0.92 and 0.89 for the right and left tibia, respectively. The reconstructed models were successfully used for clinical-grade preoperative planning in a real patient series of 52 cases. The mean differences to ground truth values for mechanical axis and tibial slope were 0.52° and 4.33°, respectively.ConclusionsWe contribute a novel framework for the 2D–3D reconstruction of bone models from biplanar standing EOS radiographs and successfully use them in automated clinical-grade preoperative planning of high tibial osteotomies. However, achieving precise reconstruction and automated measurement of tibial slope remains a significant challenge.

Metaphyseal Fixation Using Cones and Sleeves for Severe Proximal Tibial Bone Loss

BackgroundTibial bone defects are commonly encountered in revision total knee arthroplasty (rTKA) and can be managed with metaphyseal cones or sleeves. Few studies have directly compared tibial cones and sleeves in rTKA, and none have limited this comparison to the most severe tibial defects. The purpose of this study was to evaluate and compare the outcomes of metaphyseal cones and sleeves for tibial reconstruction in rTKA regarding implant fixation and clinical outcomes. MethodsA retrospective review was conducted on patients undergoing rTKA in which metaphyseal cones or sleeves were utilized for addressing metaphyseal bone loss (34 cones and 18 sleeves). Tibial bone loss was classified according to the Anderson Orthopaedic Research Institute bone defect classification, with types 2B and 3 being included. Patient-reported outcomes and postoperative complications were collected, and a radiographic evaluation of osseointegration or loosening was performed. ResultsThere were 52 knees included (34 cones, 18 sleeves), with a median follow-up of 41.0 months. All-cause implant survival was 100% at 2 years and 96% (95% confidence interval: 76 to 99%) at 4 years, with 98% of tibial components demonstrating osseointegration at the final follow-up. During follow-up, there were a total 11 revisions, of which 1 sleeve was revised secondary to implant loosening. Tibial sleeves had a higher risk of revision compared to tibial cones (P < .01), and sleeves fixed with a hybrid technique were more likely to need revision than cones fixed by the same method (P = .01). ConclusionsPorous metaphyseal tibial cones and tibial metaphyseal sleeves both performed well at a 41-month median follow-up with no difference in aseptic survivorship between the 2 constructs. Both demonstrate high rates of osseointegration, low rates of aseptic failure, and significant improvement in Knee Society Scores in patients with severe tibial defects in rTKA.

Distraction Osteogenesis by Ring Fixator in Post Traumatic Tibial Bone Loss

Background: Reconstructing segmental bone loss defects presents a significant challenge within the field of orthopedics. The purpose of this study is to assess the clinical and radiological results of using the Ilizarov technique for tibia reconstruction following traumatic bone loss. Methods: This study was a prospective study involving 30 patients who experienced tibial bone loss in the diaphysis or metaphysis following trauma. These patients were treated with a ring fixator (Ilizarov) from March 2021 to February 2023. Unfortunately, five patients were lost to follow-up, leaving a cohort of 25 patients who were observed for a duration ranging from 9 to 12 months. Results: The current study involved 25 patients with post-traumatic tibial bone loss. The age range was 14 to 48 years, with a mean age of 28.4±8.8 years. Among the cases, 18 had a moderate defect (72%), which was significantly higher than those with a minor defect (20%) (P ≤ 0.05). Deformity was less than 7° in most cases (96%), while only one case had deformity greater than 7° (4%) (P ≤ 0.05(. Leg length discrepancy was less than 2.5 cm in the majority (96%), with only one case having a 3 cm length discrepancy (4%) (P ≤ 0.05). By the end of the follow-up period, all patients showed perfect union, enabling them to engage in daily activities post-operatively. Conclusion: The success of corticotomy and solid docking relies on well-vascularized bone and soft tissue. Soft tissue compromise at the corticotomy site can hinder healthy tissue regeneration.

Management of Segmental Tibial Bone Defects With the Magnetic Motorized Intramedullary Transport Nail: A Case Series.

Critical-sized bone defects in the tibia can arise as sequelae of trauma, infection, tumor, or the treatment of congenital limb deficiencies. Treatment of these defects often requires bone transport, which has traditionally been accomplished using circular external fixators. The development of a bone transport nail facilitated tibia reconstruction through distraction osteogenesis using an all-internal device, thus avoiding the complications associated with chronic external fixation. Given the rarity of these cases, few studies have been published on the reconstruction outcomes using this implant. We sought to investigate the bone healing indices (including regenerate consolidation and time to docking site union) associated with the use of a magnetically controlled all-internal bone transport nail for the reconstruction of 4 patients treated for posttraumatic tibial bone loss. Perioperative and device-related complications are also reported.

Distally Based Pedicled Fibula Flap for Reconstruction of Distal Tibia After Oncological Resection: A Case Series and Review of Literature.

Reconstruction of distal tibial defects pose a difficult challenge because the bone is subcutaneous and close to the tendons and neurovascular bundles. Distally based pedicled fibula with retrograde flow can be used for the reconstruction of distal tibial defects. This is based on the communicating branch of the peroneal artery to the posterior tibial artery. We present three cases of distal tibia primary tumours which were resected and reconstructed using recycled autograft plus distally based pedicled fibula and ankle arthrodesis. This pedicled retrograde fibula flap is a novel technique for the reconstruction of distal tibial defects after oncological resections. It provides a vascularized graft without the need for microvascular surgery and without violating the normal limb. Meticulous dissection of and preservation of the communicating branches between the peroneal artery and the posterior tibial artery with confirmation of retrograde flow before dividing the proximal peroneal pedicle is sine quo non for the success of this graft. This flap overcomes the drawback of the limited arc of rotation and limited reach of proximal pedicle-based flap for distal tibial reconstruction. Long-term functional outcomes, limb shortening associated with this flap, and its effect on functional outcomes remain to be ascertained.

The effect of periprosthetic bone loss on the failure risk of tibial total knee arthroplasty.

The effect of long-term periprosthetic bone loss on the process of aseptic loosening of tibial total knee arthroplasty (TKA) is subject to debate. Contradicting studies can be found in literature, reporting either bone resorption or bone formation before failure of the tibial tray. The aim of the current study was to investigate the effects of bone resorption on failure of tibial TKA, by simulating clinical postoperative bone density changes in finite element analysis (FEA) models and FEA models were created of two tibiae representing cases with good and poor initial bone quality which were subjected to a walking configuration and subsequently to a traumatic stumbling load. Bone failure was simulated using a crushable foam model incorporating progressive yielding. Repetitive loading under a level walking load did not result in failure of the periprosthetic bone in neither the good nor poor bone quality tibia at the baseline bone densities. When applying a stumble load, a collapse of the tibial reconstruction was noticed in the poor bone quality model. Incorporating postoperative bone loss led to a significant increase of the failure risk, particularly for the poor bone quality model in which subsidence of the tibial component was substantial. Our results suggest bone loss can lead to an increased risk of a collapse of the tibial component, particularly in case of poor bone quality at the time of surgery. The study also examined the probability of medial or lateral subsidence of the implant and aimed to improve clinical implications. The FEA model simulated plastic deformation of the bone and implant subsidence, with further validation required via mechanical experiments.

MULTIFUNCTIONAL ORTHOPAEDIC BIOMATERIALS LOADED WITH CISPLATIN FOR LOCAL TREATMENT OF BONE TUMOURS

Residual tumor cells left in the bone defect after malignant bone tumor resection can result in local tumor recurrence and high mortality. Therefore, ideal bone filling materials should not only aid bone reconstruction or regeneration, but also exert local chemotherapeutic efficacy. However, common bone substitutes used in clinics are barely studied in research for local delivery of chemotherapeutic drugs. Here, we aimed to use facile manufacturing methods to render polymethylmethacrylate (PMMA) cement and ceramic granules suitable for local delivery of cisplatin to limit bone tumor recurrence.Porosity was introduced into PMMA cement by adding 1-4% carboxymethylcellulose (CMC) containing cisplatin, and chemotherapeutic activity was rendered to two types of granules via adsorption. Then, mechanical properties, porosity, morphology, drug release kinetics, ex vivo reconstructive properties of porous PMMA and in vitro anti-cancer efficacy against osteosarcoma cells were assessed. Morphologies, molecular structures, drug release profiles and in vitro cytostatic effects of two different drug-loaded granules on the proliferation of metastatic bone tumor cells were investigated.The mechanical strengths of PMMA-based cements were sufficient for tibia reconstruction at CMC contents lower than 4% (≤3%). The concentrations of released cisplatin (12.1% and 16.6% from PMMA with 3% and 4% CMC, respectively) were sufficient for killing of osteosarcoma cells, and the fraction of dead cells increased to 91.3% within 7 days. Functionalized xenogeneic granules released 29.5% of cisplatin, but synthetic CaP granules only released 1.4% of cisplatin over 28 days. The immobilized and released cisplatin retained its anti-cancer efficacy and showed dose-dependent cytostatic effects on the viability of metastatic bone tumor cells.Bone substitutes can be rendered therapeutically active for anticancer efficacy by functionalization with cisplatin. As such, our data suggest that multi-functional PMMA-based cements and cisplatin-loaded granules represent viable treatment options for filling bone defects after bone tumor resection.

Vascularized pedicled fibula flap with split periosteal overlay for ankle arthrodesis: Modification of technique and case report

Defects of the distal tibia, ranging from infectious to neoplastic origins, are difficult lesions to repair given their proximity to the ankle joint. Surgical repair options have often been limited, as ankle replacements and ankle arthrodesis generally require more tibial bone stock to achieve positive outcomes and avoid loss of function in the affected joint. Here we present a case of a distal tibial defect being reconstructed using a pedicled fibula flap and ankle arthrodesis technique that allowed for a sufficient range of mobility of the joint post-operatively. Our patient was a 52-year-old female with a history of myelodysplastic syndrome treated with a stem-cell transplant; fifteen months following the transplant, she was diagnosed with osteonecrosis of the distal tibia and calcaneus after developing severe swelling and pain in her left ankle. Despite conservative treatment measures, her symptoms continued to worsen, and ankle reconstruction was chosen as the only viable option for recovery. She underwent distal tibial reconstruction and tibiotalar arthrodesis using an ipsilateral vascularized pedicled fibular flap. The patient was ambulating well eight weeks post-op; she reported being able to painlessly bear full weight on the left ankle 14 weeks post-op. One-year post-op the patient was able to demonstrate an adequate range of motion of the affected joint, reduced relative to the unaffected limb but still allowing for suitable and comfortable ambulation. A 21-month post-op X-ray showed complete radiographic union of the distal tibia to the fibula flap and tibiotalar arthrodesis. As evidenced in our patient, an extremely positive postoperative outcome can be achieved with the utilization of this technique. • Split periosteal overlay in the setting of fibula flap can potentiate bony fusion. • Pedicled fibula flap can be used as viable treatment for distal tibial defects. • Pedicled fibula flap for distal tibial defects maintains the tibiotalar joint.

Global variation in isolated posterior cruciate ligament reconstruction

PurposeIn the setting of persistent instability or failed non-operative management, surgical reconstruction is commonly recommended for isolated posterior cruciate ligament (PCL) tears. The purpose of this study was to systematically review published studies to evaluate regional variation in the epidemiology of and surgical approaches to primary, isolated PCL reconstruction.MethodsA systematic review was performed in June 2022 to identify studies examining operative techniques during primary, isolated PCL reconstruction. Collected variables consisted of reconstruction technique, graft type, graft source, tibial reconstruction technique, femoral and tibial drilling and fixation methods, and whether the remnant PCL was preserved or debrided. Studies were classified into four global regions: Asia, Europe, North America, and South America.ResultsForty-five studies, consisting of 1461 total patients, were identified. Most of the included studies were from Asia (69%, n = 31/45). Single bundle reconstruction was more commonly reported in studies out of Asia, Europe, and North America. Hamstring autografts were utilized in 51.7% (n = 611/1181) of patients from Asia and 60.8% (n = 124/204) of patients from Europe. Trans-tibial drilling and outside-in femoral drilling were commonly reported in all global regions. The PCL remnant was generally debrided, while remnant preservation was commonly reported in studies from Asia.ConclusionSurgical treatment of isolated PCL injuries varies by region, with the majority of published studies coming from Asia. Single-bundle reconstruction with hamstring autograft through a trans-tibial approach is the most commonly reported technique in the literature, with males reported to undergo isolated reconstruction more often than females.Level of EvidenceSystematic review, Level IV.

Humerus nail for tibial reconstruction in adolescent with osteogenesis imperfecta – A rare surgical case report

Osteogenesis Imperfecta (OI) is a rare connective tissue disorder known for excessive bone fragility caused by collagen mutations. The common orthopaedic problems related to bone fragility include frequent multiple bone fractures, progressive deformity of long bones leading to impaired ambulation. Surgical correction of long bone deformities in OI is conventionally done using distraction osteogenesis (illizarov fixator), elastic intramedullary nailing, rigid extramedullary fixation using plates, after osteotomy. Intramedullary fixation appears to be an ideal choice for correction of recurrent deformity in the long bone and the devices used previously include telescoping rods, single or dual non-elongating nails (rush nail, TENS). Recently in a case report of 3 individual patients, a humerus nail has been used to reconstruct femur in adolescents with OI. We report a case of humerus nailing for reconstruction of tibia in an adolescent OI male with excellent outcomes which is first of its kind and not reported previously by any other authors.

Intercalary tibial reconstruction with frozen tumor-bearing autograft in combination with ipsilateral fibula in limb-salvage surgery

The purpose of this study was to examine whether the results of a reconstruction using frozen autograft in combination with vascularized fibula are comparable to other reconstructive methods in limb-salvage surgery for tibial sarcoma with regard to the functional outcome and complications. Between 2008 and 2012, nine patients with bone sarcoma of the tibia underwent excision of the affected segment that was then frozen and reimplanted with an ipsilateral vascularized fibular graft within it. Patients were examined clinically and radiographically. The mean follow-up was 48.8 months. The mean time to full weight-bearing was 6.2 months and to complete radiological union 6.8 months at the conjunction. One patient required a mid-thigh amputation due to local recurrence in soft tissue. No local recurrence arising from the frozen autograft was detected. Complications included wound dehiscence in 1, clawed toes in 1, temporary peroneal nerve palsy in 1, and stress fracture in 1. The average musculoskeletal tumor society functional score was 94.5%. Combination of a frozen tumor-bearing autograft and ipsilateral pedicled fibula is an effective reconstruction for massive bone defect arising from resection of bone sarcoma in tibia. This approach has the advantage of combining the biological properties offered by the vascularized bone graft with the mechanical endurance of the frozen autograft. The method is best indicated for intercalary defects of the tibia for selected patients. Level IV, therapeutic study.

Limb Elevation by Transcalcaneal Steinmann Pin in Lower Extremity Free Flap Reconstruction.

Lower limb elevation after free flap reconstruction is essential to achieve a satisfactory outcome, avoid pressure (on the flap or over the anastomosis), reduce edema, and prevent venous insufficiency during the first postoperative week. In the upper extremity and head and neck regions, postural measures are easier for the patient. However, achieving the required elevation and immobility for lower extremity free flaps can be a challenge. Different methods have been reported for this purpose, such as simple kickstands, kickstand external fixators,1 and transtibial pins.2,3 In our experience, a Steinmann transcalcaneal pin, described for lower limb traction,4 may offer advantages (Fig. 1).Fig. 1.: Steinmann transcalcaneal pin placed in position. The limb is raised with a Bohler stirrup and a gauze bandage.It is technically simple and rapid to place. Usually far from the surgical field, it can be used in case of tibial reconstruction. It has a low infection rate, and it can be performed under local anesthesia at the bedside if needed. Further advantages of the Steinmann pin are that it allows easier dressing changes in the postoperative period, thereby relieving patients from strict positioning and allowing them to move somewhat while in bed. The pin is placed through the calcaneus, 2 cm below the apex of the inner malleolus and 2 cm from the posterior aspect of the calcaneus in a medial to lateral direction, to avoid the calcaneal branch of the tibial nerve and the retromalleolar neurovascular bundle.5 No radiographic control is needed. The pin is tied with a Bohler stirrup and a gauze bandage to the bed box frame, thus controlling the position of the lower limb, without any pressure on the flap, and allowing correction of the equine foot tendency if needed. In the absence of stirrups, the pin can be fixed directly to a cast. This low-demand mechanical device grants a safer method than simple kickstands, is easier to use than kickstand external fixators, which require multiple pins, and prevents tibial osteomyelitis risk caused by a transtibial pin. [See Figure, Supplemental Digital Content 1, which shows tibia osteomyelitis caused by transtibial pin placement, https://links.lww.com/PRS/F39.] The only precaution to be taken should be to protect the tips of the pin. In conclusion, use of a transcalcaneal Steinmann pin allows for safe and comfortable elevation in lower extremity free flaps. DISCLOSURE The authors declare no conflicts of interest, and did not receive any form of financial or nonfinancial support.

SSOP Three-Dimensional Reconstruction of Tibia and Fibula for Applications in Biomechanical Fracture Models

Context: Non-fatal injuries represent a public health issue. Among them, lower limb fractures have a large impact on the costs related to orthopedic treatments. In this work, a three-dimensional reconstruction of the tibia and fibula was performed for biomechanical applications with the purpose of defining the 3D reconstruction parameters that allow reducing patients’ radiation exposure and computational costs. Method: For the 3D reconstruction, a computerized tomography taken from a volunteer was used, as well as two software applications specialized in DICOM image reconstruction (Mimics Research and 3DSlicer). The number of images included in the volume was modified, and the results were compared. The quality of the reconstructed volumes was verified by comparing the reference volume reconstructed with the total number of images/slices vs. the modified volumes. The MeshLab software was used for this purpose. The analyzed parameters were the distance differences between the reference and the alternative models, as well as the qualitative curvature analysis. Results: The ANOVA results for the Max (maximum distance between meshes) response shows that software and slices are significant factors. However, the software-slices interaction did not have a significant influence. As for the RMS (root mean square) distance response, software, slices, and the software-slices interaction are not significant. For the Mean distance response, slices and the software-slices interaction are not significant. Nevertheless, software significantly influences the response. These results suggest a potential way to reduce the computational cost and the patient’s radiation exposure in future biomechanical and preoperatory analyses, since the same quality can be obtained by including fewer 2D images in the reconstruction. Conclusions: The reconstructed surfaces are smoother when Mimics is used, even though the same smoothness factor was employed in both software applications during the reconstruction. When 16 slices are used (retained every 16 images from the complete original model), the distance differences increased for both bones (tibia and fibula). For the RMS, reducing the number of slices and using either one of the two applications analyzed would not show any significant differences in the reconstruction, thus allowing the potential reduction of radiation exposure of the patient. Acknowledgements: The authors are grateful to Universidad Nacional de Colombia for funding the project “Estado de esfuerzos en un elemento de osteosíntesis en la consolidación de una fractura de miembro inferior”.

Designing a better incision for proximal tibial osteosarcoma resection and reconstruction: a reminder of the skin's vascular anatomy.

Designing a better incision for proximal tibial osteosarcoma resection and reconstruction: a reminder of the skin's vascular anatomy.

The medial sural artery perforator pedicle propeller flap for lower middle-third anterior tibial soft tissue defect reconstruction: Case report and literature review

Abstract Lower extremity reconstruction still issues a challenge for plastic surgeons. The medial sural artery perforator (MSAP) flap has been reported for use to reconstruct the defects of the knee and proximal-third leg defects in many papers. But there is a few papers that described the technique of using this flap for reaching the middle third led defects. The authors report the first using MSAP propeller flap in Vietnam to cover the defect in a 45-year-old female patient who suffered from chronic ulcer with bone exposure over the middle third anterior tibial and evaluate the result of 4 months post-op. Keywords: Lower extremities defects reconstruction, perforator flap, medial sural artery perforator flap, propeller flap.