Biological Reconstruction Research Articles

Cost Utility of Various Biologic Versus Endoprosthetic Reconstruction for Primary Bone Sarcoma of the Knee

Background: Currently, the treatment of primary bone sarcoma has been developed to increase survival rate and enable patients to undergo limp sparing surgery. The cost-utility study of reconstructive surgery methods could also benefit developing treatment plans as well as national policies. Materials and Methods: The present research was conducted among 27 patients with primary bone sarcoma of the knee undergoing limp sparing surgery by analyzing the cost-utility of various biologic versus endoprosthesis reconstruction. The result reported in the quality-adjusted-life years (QALY), cost per year of well-being (Cost/QALY), ratio of additional sanitary years (QALY gain), and creating alternatives to adjust costs to an acceptable range with one-way sensitivity analysis. Results: The QALY of endoprosthesis was the highest at 5.316 years, while the lowest number was recycled bone autograft at 3.712 years. Compared with the Cost/QALY, the recycled bone autograft indicated the most breakeven method, while endoprosthesis showed the lowest. For analyzing by QALY gain, the additional investment totaled 171,314.27 THB. Conclusion: Prosthesis as a good option, have side effects and the highest number of QALY but did not breakeven. However, reducing the cost by 27.004% was almost the same as the most breakeven method. For this method, an additional investment, equivalent to the minimum wage in Thai law averaging within 1 year, was not needed because this extra investment cost only about the minimum Thai civil servant salary for 1 year. Keywords: Primary bone sarcoma of the knee; Bone reconstruction around the knee; Cost-utility analysis; Various biologic versus endoprosthesis reconstruction

Sex and stature estimations from dry femurs of Northeastern Thais: Using a logistic and linear regression approach

BackgroundSex determination and stature estimation from skeletal remains are still crucial components in creating biological profiles in forensic anthropology. The femur is particularly valuable due to its high sexual dimorphism and correlation with stature. This study aimed to develop sex estimation models and stature reconstruction equations using femoral measurements in a Northeastern Thai population. Materials and methodThe 400 dry femora were measured for its six parameters including femur maximum length (FL), femoral shaft length (FSL), femur epicondylar breadth (FEB), femur maximum head diameter (FHD), femur midshaft circumference (FMC) and femur weight (FW). Then all parameters were analyzed by using logistic regression for sex estimation and linear regression for stature reconstruction. ResultsResults showed significant sexual dimorphism across all measured parameters, with FHD being the best predictor of sex (correction rate, 88.5 %). The optimized multivariate model achieved the highest accuracy (91.0 %). For stature estimation, sex-specific equations demonstrated superior accuracy compared to combined-sex models. The FL and FSL showed the strongest correlations with stature. ConclusionThis study demonstrated the importance of population-specific standards in forensic anthropology of the femur's reliability as a valuable tool for both sex determination and stature estimation. These results contribute significantly to forensic practice in Thailand, enhancing the accuracy of biological profile reconstruction in medicolegal investigations.

A03 - BN Long Term Quality of Life Outcomes Following the Surgical Management of Complete Intrathoracic Stomach (CIS)

Abstract Background Surgery is indicated for symptomatic patients with complete intrathoracic stomach (CIS) to avoid complications (volvulus, obstruction and strangulation) associated with high morbidity. There remains limited evidence of the long-term outcomes and improvement in symptoms from this procedure. Previous large studies have been unable to compare pre-operative symptoms with their post-operative data. Although it appears the procedure has favourable outcomes, further data is required to demonstrate a significant improvement in quality of life (QoL). We therefore aim to assess the long-term outcomes, including changes to QoL and satisfaction, for patients who underwent laparoscopic biological hiatal mesh reconstruction for CIS (100%). Method Prospective data was collected from 154 consecutive GPEH (Giant Hiatus Hernia) patients intervened between March 2008- December 2023 in a large DGH. Retrospective analysis of this identified a subgroup of 34 patients with CIS. All patients underwent a laparoscopic repair with biological mesh, apart from one patient who underwent gastropexy. Outcome measures included both pre-operative and post-operative standardised GERD-Health Related Quality of Life Questionnaire (GERD-QOL) scores; complications; and patient satisfaction. Results Thirty-four patients were included (11 male:23 female) with a mean age 72 (45-83) years. All patients were symptomatic pre-operatively with heartburn (59%), dysphagia (59%), retrosternal discomfort (53%), vomiting (41%), weight loss (41%) or shortness of breath (35%). There were 4 (12%) complications and 3 (9%) 30-day mortalities. Follow up GERD-QOL questionnaires displayed 32/34 (94%) excellent scores (defined as total <5) at 6 months and 15/21 (71%) excellent scores after a median follow up of 8.5 years (72% response rate, 2 further mortalities). This demonstrated a significant improvement in scores following the procedure and long term (p<0.001). Nineteen patients (90%) were satisfied with the procedure after long term follow up (median 8.5 years). Conclusion Laparoscopic repair of complete intrathoracic stomach in this large single-centre study has demonstrated a significant improvement in symptoms and satisfaction over a median 8.5 year follow-up.

Reconstruction after proximal ulnar resection.

Reconstruction after osteoarticular resection of the proximal ulna for tumours is technically difficult and little has been written about the options that are available. We report a series of four patients who underwent radial neck to humeral trochlea transposition arthroplasty following proximal ulnar osteoarticular resection. Between July 2020 and July 2022, four patients with primary bone tumours of the ulna underwent radial neck to humeral trochlea transposition arthroplasty. Their mean age was 28 years (12 to 41). The functional outcome was assessed using the range of motion (ROM) of the elbow, rotation of the forearm and stability of the elbow, the Musculoskeletal Tumor Society score (MSTS), and the nine-item abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH-9) score. All patients were available for follow-up at a mean of 33 months (25 to 43) and were disease-free. The mean flexion arc was 0° to 105°. Three patients had complications. One had neuropraxia of the ulnar nerve. The symptoms resolved after three months. In one patient, the screw used for fixation of the triceps tendon became exposed and was removed, six months postoperatively. One patient with wound dehiscence required a local flap for soft-tissue cover, four months postoperatively. At a mean follow-up of 33 months (25 to 43), the mean flexion arc was 0° to 105°. All patients had full supination (85°) but none had any pronation. The mean MSTS score was 23.5 (23 to 24) and mean QuickDASH-9 score was 26.13 (16.5 to 35.75). Three patients had varus-valgus instability on examination, although only one had a sense of instability while working. Radial neck to humeral trochlea transposition offers a satisfactory and cost-effective biological reconstructive option after osteoarticular resection of the proximal ulna, in the short term. It provides good elbow function and, being a biological reconstruction option using native bone, is likely to provide long-term stability and durability.

Biological knee joint reconstruction using patella following giant cell tumor excision: a case report

A 20-year-old female patient presented to us with a large expansile swelling over right knee diagnosed clinically and confirmed histopathological and radiologically to be Giant Cell Tumor of upper end of Tibia involving both condyles with a breach in the posterior cortex. In this case report we tried to retain the joint function by biological reconstruction using the Patella after the wide excision of the tumor mass. A radical excision of the upper end of the Tibia was done. The Patella was used as an articular surface supported by ipsilateral Fibula and cortico-cancellous bone chips from the ipsilateral iliac crest as struts and complemented with synthetic bone graft pieces. Thus, the joint was reconstructed biologically. The case was followed for 1 year. The tumor was excised in toto, the knee joint was restored by the Patella and the bone graft struts. The results were discussed in detail.

Long-term functional outcome of limb-sparing surgery for paediatric bone sarcoma around the knee.

Surgical limb sparing for knee-bearing paediatric bone sarcoma is considered to have a clinically significant influence on postoperative function due to complications and leg-length discrepancies. However, researchers have not fully evaluated the long-term postoperative functional outcomes. Therefore, in this study, we aimed to elucidate the risk factors and long-term functional prognosis associated with paediatric limb-sparing surgery. We reviewed 40 patients aged under 14 years who underwent limb-sparing surgery for knee bone sarcoma (15 cases in the proximal tibia and 25 in the distal femur) between January 2000 and December 2013, and were followed up for a minimum of five years. A total of 35 patients underwent reconstruction using artificial materials, and five underwent biological reconstruction. We evaluated the patients' postoperative complications, survival rate of reconstruction material, and limb, limb function, and leg-length discrepancy at the final follow-up, as well as the risk factors for each. Complications were observed in 55% (22/40) of patients. The limb survival and reconstruction material rates at five and ten years were 95% and 91%, and 88% and 66%, respectively. Infection was the only risk factor in both survivals (p < 0.001, p = 0.019). In the 35 patients with limb preservation, the median International Society of Limb Salvage (ISOLS) score at the final follow-up was 80 (47% to 97%). Younger age (p = 0.027) and complications (p = 0.005) were poor prognostic factors. A negative correlation was found between age and leg-length discrepancy (R = -0.426; p = 0.011). The ISOLS scores were significantly lower in patients with a leg-length discrepancy of more than 5 cm (p = 0.005). Young age and complications were linked to an unfavourable functional prognosis. Leg-length correction was insufficient, especially in very young children, resulting in decreased function of the affected limb. Limb-sparing surgery for these children remains a considerable challenge.

Biological reconstruction: the use of a fibular flap in the treatment of diaphyseal defects in pediatric patients with malignant bone tumors

Biological reconstruction: the use of a fibular flap in the treatment of diaphyseal defects in pediatric patients with malignant bone tumors

ThP3.6 - Long Term Surgical Outcome of Complete Intrathoracic Stomach (CIS)

Abstract Background &amp; Aims Surgery is required for medically fit symptomatic CIS patients to avoid complications (volvulus, obstruction &amp; strangulation) that have high morbidity &amp; mortality. To assess the long term outcome including QOL (quality of life) for patients who underwent laparoscopic biological hiatal mesh reconstruction for CIS (100%). Methods Retrospective analysis of a prospectively collected of 34 CIS of 154 consecutive GPEH(Giant Para-Esophageal Hernia) patients intervened between March 2008- December 2023 in a large DGH. Data collected included demographics, BMI, ASA, Preoperative investigations (OGD &amp; Computerised Tomography), operative details including complications, &amp; standardised GERD-Health Related Quality of Life Questionnaire(GERD-QOL) scores of 0-5, 6-10, 11-15 &amp; more than 15 as excellent, good, fair &amp; poor respectively (pre-operatively, 6-month post-operative &amp; long-term), postoperative diet, SOB (shortness of breath) &amp; patient satisfaction. Results 34 included M:F 11: 23, age 72*(45-83) years, BMI 29 *(20-43), ASA III *(II-III). 20(59%), 20(59%), 18(53%), 14(41%), 14(41%) &amp; 12(35%) had heartburn, dysphagia, retrosternal discomfort, vomiting, weight loss and SOB respectively. 6 (18%) emergencies, 22 (65%) incomplete OGDs, operative time 210* (150-510) mins, 1(3%) conversion, 3*(9%) surgical mortality &amp; PO stay 3*(2-27) days. Pre and 6-month post surgery GERD-QOL poor (≥15) &amp; excellent (&amp;lt;5) in 21(62%) &amp; 32(94%) respectively with 32(94%) excellent satisfaction. Follow up at 102*(16-190) months had 2 more unrelated deaths, 21(72%) contacted with GERD-QOL excellent (&amp;lt;5) in 14(67%), poor 1(5%), 19(90%) solid diet, 2(10%) SOB with 19(90%) excellent satisfaction. Conclusion Favourable long term outcome achieved here supports complex surgery for this debilitating condition in the medically fit symptomatic elderly patients. * Median

Graft Infections in Biologic Reconstructions in the Oncologic Setting: A Systematic Review of the Literature.

Background: Biologic graft infection (BGI) is one of the main complications in graft reconstructions. However, very little evidence exists regarding the epidemiology of BGI, as most of the data come from sparse reports. Moreover, most of the series did not detail the treatment and outcome of graft infections. The aim of this systematic review of the literature is to provide a comprehensive data collection on BGI after oncologic resections. Methods: Three different databases (PubMed, Scopus, and Web of Science) were searched for relevant articles, and further references were obtained by cross-referencing. Results: 139 studies met the inclusion criteria. A total of 9824 grafts were retrieved. Among these, 684 (6.9%) were in the humerus, 365 (3.7%) in the pelvis, 2041 (20.7%) in the femur and 1660 (16.8%) in the tibia. Most grafts were osteoarticular (2481, 26.7%) and intercalary 2112 (22.7%) allografts. In 461 (5.0%), vascularized fibula grafts (VFGs) were used in combination with recycled autografts. Recycled grafts were reported in 1573 (16.9%) of the cases, and allograft-prosthetic composites in 1673 (18.0%). The pelvis and the tibia had the highest incidence of BGI (20.4% and 11.0%, respectively). The most reported first treatment was debridement and implant retention (DAIR) in 187 (42.8%) cases and two-stage revision with graft removal in 152 (34.8%). Very little data are reported on the final outcome specified by site or type of graft. Conclusions: This systematic review of the literature confirms a high incidence of infections in biologic reconstructions after resections of primary bone tumors. Despite DAIR being a viable attempt, in most cases, a two-stage approach with graft removal and reconstruction with endoprosthesis presented the highest chance to overcome infection, guaranteeing a reconstruction. We emphasize the need for future multicentric studies to focus on the management of infections after biological reconstructions in bone sarcomas.

Does liquid nitrogen recycled autograft for treatment of bone sarcoma impact local recurrence rate? A systematic review

The gold standard treatment for primary bone sarcomas has been surgical resection with wide margins. However, there is no consensus regarding an optimal method for limb salvage reconstruction. In 2005, a technique for recycling resected bone after intraoperative treatment with liquid nitrogen was described. This technique has been reported to have a spectrum of advantages; nonetheless, acceptance for routine use has been limited, primarily for fear of local recurrence. A systematic search of the literature using PubMed and Google Scholar was performed. Full-text articles published between 2008 and 2023 were included if the study presented sufficient information regarding patients with a diagnosis of a primary bone sarcoma of the limbs or pelvis who had undergone reconstruction with liquid nitrogen recycled autografts. Sixteen studies that included 286 patients met criteria for analyses. Local recurrence occurred in 25 patients (8.7 %) during the first 4 years following limb salvage reconstruction using recycled autografts for treatment of primary bone sarcomas, which compares favorably to the 15–30 % local recurrence rates reported for patients undergoing limb salvage reconstruction using artificial implants. Systematic synthesis of the current evidence regarding local recurrence rates following use of the liquid nitrogen recycled autograft technique for limb salvage reconstruction after bone sarcoma resection suggests a favorable comparison to other limb salvage reconstruction options. As such, this technique warrants further consideration as a viable option for indicated patients based on relative advantages regarding costs, availability, and biologic and surgical reconstruction benefits.

Treatment of pediatric bone tumors around the knee

Primary bone tumors are rare but more frequently seen during childhood and with predilection for the distal femur and proximal tibia. Therapy of benign tumors-if indicated-includes surgical resection in most cases, whereas malignant bone tumors such as osteo- and Ewing's sarcomas are treated with chemotherapy, wide resection and/or radiation therapy (Ewing's sarcoma). The reconstruction of emerging bone defects is significantly influenced by surgeon-related preferences and tumor-associated factors, respectively. Double-barrel vascularized fibula grafts or extracorporeally irradiated autografts in combination with afree fibula transplant are preferred biological reconstruction techniques around the knee joint. In cases in which the knee joint cannot be preserved, reconstruction is performed using tumor endoprostheses, but potentially emerging leg length discrepancies after resection of apotent physis must be taken into account. In considerably young patients, rotationplasty might represent aviable option with promising functional results.

Enhancing the biological integration of massive bone allografts: A porcine preclinical in vivo pilot-study

Critical bone loss can have several origins: infections, tumors or trauma. Therefore, massive bone allograft can be a solution for limb salvage. Such a biological reconstruction should have the ideal biomechanical qualities. However, their complication rate remains too high. Perfusion-decellularization of massive allografts could promote the vitality of these grafts, thereby improving their integration and bone remodeling.Three perfusion-decellularized massive bone allografts were compared to 3 fresh frozen massive bone allografts in a preclinical in vivo porcine study using an orthopedic surgery model. Three pigs each underwent a critical diaphyseal femoral defects followed by an allogeneic intercalary femoral graft on their both femurs (one decellularized and one conventional fresh frozen as “native”) to reconstruct the defect. Clinical imaging was performed over 3 months of follow-up. The grafts were then explanted and examined by non-decalcified histology, fluoroscopic microscopy and immunohistochemistry.Bone consolidation was achieved in both groups at the same time. However, the volume of bone callus appeared to be greater in the decellularized group. Histology demonstrated a superior bone remodeling in the decellularized group, with a higher number of osteoclasts (p < 0.001) and larger areas of osteoid matrix and newly formed bone as compared to the “native” group. Immunohistochemistry showed a superior vitality and remodeling in both the cortical and medullary cavities for osteocalcin (p < 0.001), Ki67 (p < 0.001), CD3 (p < 0.001) and α-SMA (p < 0.001) as compared the “native” group. Three months after implantation, the decellularized grafts were proven to be biologically more active compared to native grafts. Fluoroscopic microscopy revealed more ossification fronts in the depth of the decellularized grafts (p = 0.021).This pilot study provides the first in vivo demonstration on the enhanced biological capacities of massive bone allograft decellularized by perfusion as compared to conventional massive bone allografts.

Advancing pediatric bone sarcoma care: navigating complications and innovating solutions in limb salvage and reconstruction-why, when, and how to treat limb length inequalities.

Pediatric bone sarcomas, particularly osteosarcomas, present unique challenges in the realm of orthopedic oncology, given their predilection for the metaphyseal regions of long bones and the intricate balance required between achieving oncologic control and preserving limb function. This abstract encapsulates findings from a comprehensive review aimed at advancing pediatric bone sarcoma care, focusing on navigating the complications and innovating solutions for complications of limb salvage and reconstruction focusing on limb length inequalities and accompanying bone defects. Advancements in imaging, surgical techniques, and adjuvant therapies have shifted the paradigm from amputation to limb-sparing surgeries, albeit with significant challenges, especially in young patients where growth potential complicates reconstructive outcomes. The series highlights the complexity of managing limb length discrepancies (LLD), the cornerstone of limb salvage challenges, and the innovative approaches to address them, including modular endoprosthetic reconstruction with expandable prostheses, magnetic lengthening nails and biological reconstruction strategies like vascularized fibula grafts. This review underlines the importance of a multidisciplinary approach in managing pediatric bone sarcomas, where the aim extends beyond mere survival to ensuring quality of life through functional limb preservation. It highlights the need for ongoing innovation in surgical and reconstructive techniques tailored to the pediatric population's unique needs, emphasizing the potential of emerging technologies and methodologies to improve outcomes. Future research should aim to fill the existing knowledge gaps, particularly in comparing pediatric and adult surgical outcomes, to refine treatment protocols and improve patient care in this challenging domain.

1004 Urgent Explant of Infected Aortic Stent Graft in a Patient with Kidney Transplant Using Biological Aortoiliac Reconstruction and a Temporary Axillo-Femoral Perfusion Shunt: 6-Year Follow-Up and Literature Review

Abstract Background Written consent obtained for case report. A 59-year-old male who was 3-months post-EVAR repair under immunosuppression for kidney transplantation and anti-retroviral HIV treatment presented to ED in 2017 with abdominal pain and fever. CTAP revealed pyelonephritis in renal allograft. Blood cultures were positive for staphylococcus epidermidis. PETCT showed high-intensity uptake around endograft. Urgent explant of endograft and insitu biological aorto-biiliac graft reconstruction with bench prepared bilateral long saphenous veins were performed. Results The predicted challenges were locating source of infection, immunosuppressed state, and allograft preservation. Dacron graft was used as temporary perfusion shunt (left axillary artery to right superficial femoral artery) for renal allograft on right external iliac vessels. Endograft was removed via rooftop incision with visceral rotation. Supra-celiac and supra-superior mesenteric artery clamping times were 15 and 35 minutes. The source of infection was from infected appendix proximal to graft with erosion of right external iliac artery resulting in appendectomy in the same operation. Following 12-weeks of OPAT antibiotic-therapy, repeat PETCT revealed low-grade uptake around aortic graft and inflammatory markers were back to baseline. At 6 years in 2023, patient remains clinically well with ∼20% allograft function. Maintaining kidney allograft perfusion in the setting of elective non-infected aortic graft explant was previously reported, but with ENROUTE system (Rasheed et al., 2018). Conclusions The satisfactory long-term outcomes discussed here demonstrated with MDT planning involving vascular surgery, infectious diseases, renal medicine and patient, explant of infected graft with insitu biological graft reconstruction in renal transplant patients presenting with complex aortic-graft infection is feasible.

2D and 3D visualization of herbaceous plant–plant contact zones using high‐resolution X‐ray computed tomography (HRXCT)

Societal Impact StatementParasitic plants that deprive crops of water and nutrients are an increasingly concerning food security issue, affecting the livelihood of millions of subsistence, small‐ and mid‐scale farmers. An in‐depth understanding of parasite–host interactions is required to develop species‐specific and ecologically sustainable parasite management methods. The non‐invasive visualization of herbaceous contact zones, applicable to diverse parasite–host pathosystems presented in this study, brings methodological advance to the research of biotic interactions between crops and plant parasites belonging to the most devastating parasitic plant family (Orobanchaceae). This work also provides first insights into how the parasites' feeding organ displaces host tissue beyond the direct parasite–host interface.SummaryHigh‐resolution X‐ray computed tomography (HRXCT) enables sectioning‐free two‐dimensional imaging of biological structures and reconstruction of three‐dimensional objects. Although its application is common in many areas of biomedicine and despite its flexibility regarding resolution levels, the technology remains underutilized in the plant sciences. Here, we explored HRXCT for the study of parasitic plant–plant interactions by developing protocols to access soft‐tissue host–parasite contact zones at cell‐level resolution. We tested various sample preparation methods and contrast stains for their efficiency to improve the imaging of haustorium samples. In doing so, we achieved cellular resolution with the visible cellular organization of haustorial structures, especially of the vascular system. Fresh stained and dehydrated sample preparation of soft haustoria enables the highest spatial resolution with fine‐cellular discrimination of haustorium versus host cells. Application of cell‐level resolved HRXCT to five pathosystems: Alectra‐cowpea, Phelipanche‐tomato, Phtheirospermum‐tomato, Rhamphicarpa‐tomato, and Striga‐sorghum highlighted a life history‐specific organization and uncovered an as yet undescribed internal displacement of host tissue at parasite–host interfaces. Following image‐based training, our HRXCT approach could invoke AI‐based cell recognition for automated parasite cell–host cell differentiation. Superseding extensive microsectioning for 3D imaging, the newly established HRXCT protocol for 2D‐ and 3D‐visualization of herbaceous plant–plant contact zones and the first insights gained from it, is useful for mid‐throughput, comparative studies of parasitic plant–host interactions.

Distraction Osteogenesis Reconstruction Following Resection of Bone Sarcomas: Surgical, Functional, and Oncological Outcomes from a Prospective Trial Analysis.

While sustainable long-term function has been established for biological reconstruction with distraction osteogenesis (DO) following osseous resections, there is a paucity of published data informing surgeons and patients on important milestones in the reconstructive process. The objectives of this study were to determine when to expect complete bone healing and full weight-bearing as well as to quantify the influence of chemotherapy on the osseous regeneration process. Prospectively, pathological and clinical data were collected for 30 consecutive patients who underwent primary or secondary DO-based reconstruction following osseous resection from 2018 to 2021. Serial radiographs indicated the times to cortex formation and full union. An unpaired t test was used to compare the time required for full bone remodeling of segments transported with and without concurrent chemotherapy. The average resection length was 13.6 cm (range, 4 to 22 cm). Patients underwent an average of 6.1 procedures (range, 1 to 14 procedures). Half (50%) of all procedures were planned, while half were unplanned procedures. All patients achieved full, independent weight-bearing at a median of 12 months (interquartile range [IQR], 9 to 16 months). For the 34 segments transported concurrently with chemotherapy, the mean bone healing index (BHI) was 2.3 ± 0.7, and the mean BHI was 1.2 ± 0.4 for the 25 segments without chemotherapy at any point during their transport (p < 0.0001). All 30 patients achieved full bone healing and independent weight-bearing at a median of 1 year postoperatively and continued to show functional improvement afterward. Surgeons and patients can expect bone healing to be nearly twice as fast for segments transported after completion of systemic chemotherapy compared with segments transported concurrently with adjuvant chemotherapy. Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence.

Infection of surgery for bone and soft tissue sarcoma with biological reconstruction: Data from the Japanese nationwide bone tumor registry

BackgroundAlthough biological reconstruction (such as recycled autograft, vascularized autograft, allograft, or bone transport) is possible for bone defects after malignant bone or soft tissue tumor resection, a high incidence of postoperative complications, including infection, poses a problem. The difficulty in accumulating cases has resulted in a lack of reliable etiological information, such as the incidence and risk factors of postoperative infections. MethodsWe conducted a retrospective study on the nationwide registry data. The primary endpoint was the need for additional surgical intervention for infection control. The overall incidence of postoperative infection and the related risk factors were analyzed. ResultsWe included 707 malignant bone and soft tissue tumors with biological reconstruction, including recycled autograft, vascularized autograft, allograft, bone transport, and combinations of these. The incidence of postoperative infection was 10.8%. Patients reconstructed by pedicled autograft showed a higher incidence of infection, while cases involving the combination of recycled and pedicled autograft or allograft showed a lower incidence. Independent risk factors for infection included age over 17, tumor diameter over 10 cm, the tumor located on the trunk or being high grade, reconstruction by pedicled autograft, and delayed wound healing. ConclusionInfection incidence was comparable to those in previous reports. Several conventional and novel risk factors were extracted by administering nationwide registry data. Data from the nationwide registry was informative for analyzing the incidence of postoperative infection in biological reconstruction with malignant bone and soft tissue tumor resection.

Joint-Sparing Resection around the Knee for Osteosarcoma: Long-Term Outcomes of Biologic Reconstruction with Vascularized Fibula Graft Combined with Massive Allograft.

(1) Background: We aim to address the following questions. What was the complication rate of vascularized fibula graft (VFG) combined with massive allograft in patients treated with joint-sparing resection around the knee for a high-grade osteosarcoma? What was the long-term survivorship of VFG free from revision and graft removal? What were the functional results as assessed by the Musculoskeletal Tumor Society (MSTS) score? (2) Methods: 39 patients treated in our unit for osteosarcoma around the knee with intercalary resection and reconstruction with VFG combined with massive allograft were included; 26 patients underwent intercalary tibial resection, while 13 underwent intercalary femoral resection. (3) Results: Mean Follow-Up was 205 months (28 to 424). Complications that required surgery were assessed in requiring surgical revision in 19 patients (49%) after a mean of 31 months (0 to 107), while VFG removal was necessary in three patients (8%). The revision-free survival of the reconstructions was 59% at 5 years and 50% at 10 to 30 years. The overall survival of the reconstructions was 95% at 5 to 15 years and 89% at 20 to 30 years. The mean MSTS score was 29.3 (23 to 30). (4) Conclusions: VFG represents an effective reconstructive option after joint-sparing intercalary resection around the knee for osteosarcoma.

Effect of Plate Configuration in the Primary Stability of Osteotomies and Biological Reconstructions of Femoral Defects: Finite-Element Study.

Osteosynthesis is an alternative treatment for stabilizing femur-bone traumas. The initial stability of the fixation systems is one of the biomechanical parameters affecting implant failure and bone union, especially in surgeries of intercalary reconstructions after the removal of bone tumors. This study aimed to investigate the initial biomechanical effect of using one or two osteosynthesis plate configurations for femoral fixation and the effect of fastening the allograft to the osteosynthesis plate in the case of femoral allograft reconstructions. Three finite-element models of a femur with three different fixation conditions for a transverse osteotomy in the middle of the diaphysis, i.e., using one and two osteosynthesis plates and an intercalary allograft, were constructed. An eight-hole compression plate and a six-hole second plate were used to simulate osteosynthesis plates. The plate screws were tightened previously to the loading, and the tightening sequences simulate the bolt-tightening procedure in a surgical environment. The models were imported into the ADINA System for nonlinear analysis, using compression loads applied over the femur head. Models with the dual fixation systems had the most outstanding compression stiffness. The femur head movement in the dual plate system was 24.8% smaller than in the single plate system. A statistical analysis of a region of interest (VOI) placed in the femur diaphysis showed that the biomechanical effect of using the dual plate system is smaller in the osteotomy region than at the femur head, e.g., a displacement average decrease of only 5% between the two systems, while the maximum value decreases by 26.8%. The allograft fixation to the second osteosynthesis plate leads to an improvement in the system stability. The results presented in this work show that including the bolt analysis in the femoral diaphysis osteotomy fixation will allow for capturing the nonlinear behavior of the osteotomy region more realistically. The stability of the intercalary reconstruction of the femoral diaphysis was higher when the allograft was fastened to the second osteosynthesis plate.

Functional and oncological outcomes of patients with proximal humerus osteosarcoma managed by limb salvage.

Osteosarcoma is the most common primary bone malignancy in skeletally immature patients. The proximal humerus is the third most common site of osteosarcoma. The literature shows a paucity of published data concerning the outcome of proximal humerus osteosarcoma managed by limb salvage. The purpose of this study was to answer the following questions: (1) do patients with proximal humerus osteosarcoma managed by limb salvage and neoadjuvant chemotherapy show good functional and oncological outcomes, and (2) are there any prognostic factors that are associated with better oncological and functional outcomes? The study was a retrospective case series study assessing the overall outcome of 34 patients with proximal humerus osteosarcoma. Eighteen patients were males (53%) while 16 were females. Biological reconstruction was done in 15 patients (44%), while nonbiological reconstruction was done in 19 patients. Resections were mainly intraarticular (82%). Functional outcome was assessed using the Musculoskeletal Tumor Society (MSTS) score, while oncological outcome was assessed based on local recurrence and development of chest metastasis. Comparisons between quantitative variables were done using the nonparametric Mann-Whitney test. To compare categorical data, the chi-square (χ2) test was performed. The exact test was used instead when the expected frequency was less than 5. Correlations between quantitative variables were examined using the Spearman correlation coefficient. The mean MSTS score was 25.5 (range 23-29). A younger age was statistically correlated with a poorer MSTS score (P = 0.0016). Six patients out of 34 (17.6%) had local recurrence and four of them (67%) were treated by forequarter amputation. 41% of patients developed chest metastasis, and the majority of them were treated by chemotherapy (71%). In comparison with patients with osteosarcoma at other sites who were also managed in our institution, proximal humerus osteosarcoma patients showed higher incidence rates of local recurrence and chest metastasis along with lower 5-year patient and limb survivorships compared to distal femur, proximal tibia and proximal femur osteosarcoma patients. Treatment of osteosarcoma of the proximal humerus by limb salvage and chemotherapy yields a good functional outcome. The method of reconstruction does not impact the resultant function. The 5-year survivorship of these patients is 65%. Younger patients have a better oncological outcome and an inferior functional outcome. Level IV therapeutic study.