Massive Allografts Research Articles

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.

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.

Use of 3D-Printed Implants in Complex Foot and Ankle Reconstruction.

Treatment of traumatic critical-sized bone defects remains a challenge for orthopaedic surgeons. Autograft remains the gold standard to address bone loss, but for larger defects, different strategies must be used. The use of 3D-printed implants to address lower extremity trauma and bone loss is discussed with current techniques including bone transport, Masquelet, osteomyocutaneous flaps, and massive allografts. Considerations and future directions of implant design, augmentation, and optimization of the peri-implant environment to maximize patient outcome are reviewed.

Intercalary Resection of the Tibia for Primary Bone Tumors: Are Vascularized Fibula Autografts With or Without Allografts a Durable Reconstruction?

Intercalary Resection of the Tibia for Primary Bone Tumors: Are Vascularized Fibula Autografts With or Without Allografts a Durable Reconstruction?

Is liquid nitrogen recycled bone and vascular fibula combination the biological reconstruction of choice in lower extremity long bone tumor-related defects?

Combination techniques, which encompass the combined use of vascularized bone grafts with massive allografts or autografts (recycled bone grafts), are especially important in the biological reconstruction of tumor-related lower extremity long bone defects. Liquid nitrogen recycled bone (frozen autograft) and free vascular fibula graft (FVFG) combination, which was coined as the "frozen hotdog (FH)" method by the authors, has not been as widely used nor its outcomes reported for significantly sized patient groups. This study aims to provide an answer to whether FH is a safe and effective reconstructive tool for limb salvage in malignant tumors of the lower extremity regarding radiological, functional, and oncological outcomes. Sixty-six (male/female: 33/33) patients, who underwent FH reconstruction for tumor-related massive defects of lower extremity long bones between 2006 and 2020, were retrospectively analyzed. The mean age was 15.8 (3.8-46.7) years. The most common tumor localizations were distal femur (42.4%) and proximal tibia (21.2%) while classic osteosarcoma and Ewing's sarcoma were the most common pathologies (60.6% and 22.7%, respectively). Mean resection and FVFG lengths were 160 (90-320) mm and 192 (125-350) mm, respectively. The mean follow-up was 73.9 (24-192) months. The mean MSTS score was 25.4 (15-30) and the mean ISOLS radiographic score was 22.6 (13-24). Mean time to full weight bearing without any assistive devices was 15.4 (6-40) months and the median time was 12 months. MSTS score negatively correlated with resected segment length and vascular fibula length (p < 0.001; p = 0.006). Although full contact apposition of the FH segment correlated with earlier full weight bearing compared to partial apposition (mean 13.7 vs. 17.9 months) (p = 0.042), the quality of reduction did not affect the ISOLS radiographic score at LFU. Overall limb survival rate was 96.3% at 5 and 10 years while FH survival rate was 91.0% and 88.1% at 5 and 10 years. Local recurrence-free survival rates were 88.8% and 85.9%, and overall survival was 89.9% and 86.1% at 5 and 10 years, respectively. Limb length discrepancy was the most common complication with 34 (51.5%) patients while shell nonunion was seen in 21 (31.8%) patients and graft fracture in 6 (9.1%). The "FH" method is a safe, effective, and extremely cost-efficient reconstructive tool for tumor-related lower extremity long bone defects. Patient compliance to protracted weight-bearing, ensuring the vitality of the FVFG, and achieving an oncologically safe resection are key factors for a successful outcome.

Are Vascularized Fibula Autografts a Long-lasting Reconstruction After Intercalary Resection of the Humerus for Primary Bone Tumors?

A vascularized fibula graft (VFG) is the vascular autograft most frequently used to restore large segmental long bone defects, particularly in the upper limb. Because the use of a vascularized fibula involves an operation in an uninvolved extremity with potential morbidity, it is important to document that this type of reconstruction is successful in restoring function to the humerus. However, the long-term results of VFG after intercalary resection of the humeral diaphysis for bone tumors are still unknown. (1) What was the complication rate of reconstruction? (2) What was the functional result after surgical treatment, as assessed by the Musculoskeletal Tumor Society (MSTS) score, the American Shoulder and Elbow Society (ASES) score, and Constant score? (3) What was the survivorship of these grafts free from revision and graft removal at 5, 10, and 15 years? Between 1987 and 2021, 127 patients were treated at our institution with en bloc resection for a primary malignant or an aggressive benign bone tumor of the humerus; we excluded patients treated with extra-articular resection or amputation. Of those, 14% (18 of 127) were treated with intercalary resection of the humeral diaphysis for primary bone tumors and reconstruction with VFG, with or without a bulk allograft, and were analyzed in this retrospective study. Generally, our indications for reconstruction with VFG are intercalary resection of the humerus for primary malignant or aggressive benign bone tumors in patients with long life expectancy and high functional demands, in whom adequate bone stock of the proximal and distal epiphysis can be preserved. In 13 patients, VFG was used alone, whereas in five patients, a massive allograft was used. Our policy was to use VFG combined with a massive allograft in patients undergoing juxta-articular joint-sparing resections in which proximal osteotomy was performed close to the anatomic neck of the humerus to obtain more stable fixation and better tendinous reattachment of the rotator cuff and deltoid. All 18 patients who were treated with a VFG were available for follow-up at a minimum of 2 years (median follow-up 176 months, range 26 to 275 months), and although three have not been seen in the past 5 years and are not known to have died, they had 172, 163, and 236 months of follow-up, and were included. The median age at surgery was 25 years (range 2 to 63 years), the median humeral resection length was 15 cm (range 8 to 21 cm), and the median fibular length was 16 cm (range 12 to 23 cm). Complications and functional scores were ascertained by chart review that was performed by an individual not involved in patient care. Functional results were assessed with the MSTS score (range 0 to 30), the ASES score (range 0 to 100), and the Constant score (range 0% to 100%). Survivorship was estimated using a Kaplan-Meier survivorship estimator, which was suitable because there were few deaths in this series. Seven patients underwent a revision procedure (one radial nerve transient palsy because of screw impingement, four nonunions in three patients with one humeral head avascular necrosis, treatment for screw-related pain in one patient, and two VFG fractures), and one patient underwent VFG removal. Donor site complications were observed in four patients (one ankle valgus deformity and three claw toes-the first toe in two patients and the other toes in the third). At the final clinical control, at a median follow-up of 176 months (range 26 to 275 months), the median MSTS score was 30 of 30 (range 28 to 30), the median ASES score was 98.3 (range 93 to 100), and the median Constant score was 93.5% (range 79% to 100%). Revision-free survival was 71% (95% CI 53% to 96%) at 5 years and 57% (95% CI 37% to 88%) at 10 and 15 years; VFG removal-free survival was 94% (95% CI 83% to 100%) at 5, 10, and 15 years. VFG appears to be an effective reconstructive option after humeral intercalary resection for primary bone tumors. These are complex procedures and should be performed by an experienced team of surgeons who recognize that complications may occur frequently in the first years after the procedure. The frequency of mechanical complications observed in the first 5 years postoperatively may be lessened by using long spanning-plate fixation, and if successful, this reconstruction provides a long-term, durable reconstruction with excellent functional results. Level IV, therapeutic study.

A quantitative CT analysis of fibula inlayed in a massive allograft for femoral diaphysis reconstruction

IntroductionIn diaphyseal reconstructions for bone tumor resection, massive bone allografts (MBA) are historically regarded as the gold standard. However, these are not without complications, and they present an elevated risk of infection, nonunion and structural failure that increases over time as the graft remains largely avascular. To counteract this disadvantage, a combination of allograft with a vascularized fibula has been proposed. The aim of our study was to objectively review the results of combined vascularized fibula-allograft constructs compared to plain allograft reconstruction for bone defects in tumor patients and to assess fibular vitality predictive factors from imaging studies. Materials and methodsOur data was retrospectively reviewed for patients with femoral diaphysis reconstructions in the past ten years. Ten patients (six males and four females) with a mean average follow-up time of 43.80 months (range 20–83, SD 18.17) with combined graft (Group A) were included in the study. As a control group 11 patients (six males and five females) with a mean average follow-up of 56.91 months (range 7–118, SD 41.33) with a simple allograft reconstruction were analyzed (Group B). Demographic and surgical data, adjuvant therapy as well as complications were analyzed in both groups. Both groups were assessed with plain radiographs for bony fusion at the osteotomy sites. Patients in “Group A” had consecutive CT scans at 6 months and then annually to check for potential bone stock and bone density changes. We analyzed total bone density as well as incremental changes in three different areas of the reconstruction. This was done at two defined levels for each patient. Only patients with at least two consecutive CT scans were included in the study. ResultsThere were no statistical differences between the groups in terms of demographics, diagnosis or adjuvant therapy (p = 1.0). The mean average surgical time (599.44 vs 229.09) and mean average blood loss (1855.56 ml vs. 804.55 ml) were significantly higher in the combined graft group A (p < 0.001 and p = 0.01, respectively). The mean average length of resection (19.95 cm vs. 15.50 cm) was higher in the combined graft group (p = 0.04). The risk for non-union and infectious complication was higher in the allograft group, however, the difference was not significant (p = 0.09 and p = 0.66, respectively). The mean average time to union at junction sites was 4.71 months (range 2.5–6.0, SD 1.19) for cases of successful fibula transfer, 19.50 months (range 5.5–29.5, SD 12.49) for the three cases where we presumed the fibula was not viable and 18.85 months (range 9–60, SD 11.99) for the allograft group. The difference in healing time was statistically significant (p = 0.009). There were four cases of non-union in the allograft group.Seven out of ten patients in Group A exhibited incremental changes in all CT scan measured values. This difference was statistically significant already at 18 months from the index surgery (p = 0.008). The patients with a non-viable fibula had a smaller increase in the percentage of total bone density area measured in the CT scan compared to those patients with a successful fibula transfer (4.33, SD 2.52 vs. 52.29, SD 22.74, p = 0.008). The average bone density incremental increase in-between the fibula and allograft was different among patients with an unsuccessful fibula transfer (32.22, SD 10.41) and the ones with a viable fibula (288.00, SD123.74, p = 0.009). Bony bridges were observed in six cases of viable fibula and in none of the tree presumably dead fibulas (p = 0.03). The mean average MSTS score was higher for the subgroup of successful fibular transfer (26.7/30, SD 2.87) when compared to the group of non-viable fibular graft (17.00/30, SD 6.08) and this was also statistically significant (p = 0–007). ConclusionA viable fibula enhances incorporation of the allograft and decreases the risk for both structural failure as well as infectious complications. Viable fibula also contributes to better functional status of the recipient. Consecutive CT scans proved to be a reliable method for assessing fibular vitality. When no measurable changes are present at 18-month follow-up, we can declare the transfer unsuccessful with a good amount of certainty. These reconstructions behave as simple allograft reconstructions with analogue risk factors. The presence of either axial bridges between the fibula and allograft or newly formed bone on the inner surface of the allograft is indicative of a successful fibular transfer. The success rate of fibular transfer in our study was only 70% and skeletally mature and taller patients seem to be at increased risk for failure. The longer surgical times and donor site morbidity therefore warrant stricter indications for this procedure.

What's New in Musculoskeletal Tumor Surgery.

What's New in Musculoskeletal Tumor Surgery.

334.9: Custom Bone Massive Allograft for Lower Limb Salvage Surgery, the Impact of Imaging and 3D Printing. Experience of the Tissue Bank of the Hospital Luis Vernaza (2016-2021)

Introduction: Luis Vernaza Hospital tissue bank implemented the anatomical engineering service, which performs the activities of digitizing stored tissues, virtual surgical planning of custom tissues, and the generation of cutting guides for efficient osteotomies between donor and recipient. The main use of this technology is to provide allografts of the proximal tibia or distal femur for salvage surgery of the lower limb, with which it has been possible to restore the mobility and functionality of the knee to patients with bone tumors. With this technology, we have managed to deliver custom allografts with a discrepancy of 1 to 2 mm between the measurements of the recipient and that of the donor, in addition to obtaining three-dimensional measurements such as the curvature of the femoral condyle and the curvature of the femorotibial joint. Objective: To present the results obtained by the anatomical engineering service in the development of custom fabrics for lower limb salvage surgery. Materials and Methods: The complete knee joint, including 20 cm of the distal femur and 20 cm of the proximal tibia, is obtained from cadaveric donors. Then we proceed with the digitalization of the tissues using computed axial tomography, a service provided by the imaging center of the Luis Vernaza Hospital. At the time of requesting a graft, the specialist attaches the tomography of the recipient with the indications and measurements of the graft to be requested. The search for the graft is carried out with it in the digital catalog of the tissue bank and using the Mimics anatomical engineering software using segmentation in volumes, the approximate measurements between recipient donors are obtained. Analyzing the curvature of the femoral condyle and the surface of the tibial plateau. With the indicated stockings, we proceed with the processing of the tissue, extracting the required tissue and the ligamentous elements necessary for its subsequent fixation. Results: Thanks to this technology, it has been possible to restore mobility to 10 patients aged between 15 and 56 years. The most frequent pathology was osteosarcoma (6) followed by giant cell tumor and metastasis from other sites. The most requested graft was the proximal tibia 6 requested units, distal femur 3 units, and 1 humerus. Approximately the amount of tissue replaced was 15 cm. Discussions and Conclusions: It is difficult to obtain a synthetic replacement for the proximal tibia or distal femur, due to their multiple compositions (bone tissue, cartilage, and ligamentous fixing elements). Applying this technology to the tissue bank avoids the amputation of limbs due to lack of elements for reconstruction, because of which the allograft from a cadaveric donor with the exact stockings allows rapid restoration of the patient’s mobility and return to their usual activities.

FEATURES OF REPLACEMENT OF EXTENSIVE POST-RESECTION BONE DEFECTS IN PELVIC AND SACRAL TUMORS

Purpose of the study . To represent the results of a two-stage surgical treatment in patients with extensive pelvic bone defects. Materials and methods . Data on 7 patients who underwent surgery for pelvic and sacrum tumors at the National Medical Research Centre for Oncology from 2016 up to 2020 are presented. The average age of the patients was 36 years. Patients with massive tumors that required a major resection of the posterior pelvis and the formation of an extensive bone defect requiring reconstruction with massive allografts and implants were selected for the study. 5 patients underwent different variations of sacrectomies with the resection of the iliac bones; 2 patients – interiliac-abdominal resections. For all these patients, surgical treatment was split into 2 stages. Results . At the first stage we performed: 5 surgical interventions (total or extended sacrectomy at L5–S1 with lumbar-iliac bilateral stabilization with an 8‑screw pedicle system) in patients with sacral tumors. In 2 cases, an interilio-abdominal resection with the defect replacement with cement articulating spacer. Intraoperative blood loss on average was 1.8L. We used autohemotransfusion to compensate the intraoperative blood loss. The 2nd (reconstructive) stage was completed on average after 3 months. The reconstructive stage was not accompanied by major trauma in all patients. The average blood loss was approximately 800 ml. There were no complications after the reconstructive surgical stage. Conclusion . The described two-stage technique allowed to avoid severe infectious complications requiring removal of implants and grafts in all patients. Adequate spinal pelvic stabilization and/or spacing of the defect contributed to early functional rehabilitation of patients and the continuation of adequate adjuvant therapy in the interstage period. The delaying of the reconstruction allowed to reduce the duration and invasiveness of the main intervention without affecting the final result of treatment.

Intercalary reconstruction of long bones by massive allograft: Comparison of construct stability ensured by three different host-graft junctions and two types of fixations in a synthetic femur model.

An intercalary segmental allograft is an option for limb salvage in bone tumours. Stable and congruent intercalary reconstructions are a prerequisite for achieving host-graft union. However, a too rigid fixation could increase the risk of late complications correlated with negative bone remodelling. This study compared the reconstruction stiffness achieved by three different host-graft junctions, namely, end-to-end, modified step-cut, and taper. A low-stiffness bone plate was used as the fixation method, except for the taper junction where a low-stiffness intramedullary nail was also used to investigate the effects of different types of fixation on construct stiffness. Composite femora were tested under four loading conditions to determine coronal and sagittal bending stiffness, as well as torsional stiffness in opposite directions. Stiffness values were expressed as a percentage of intact host bone stiffness (%IBS). While a reduction of coronal bending stiffness was found with taper junctions (76%IBS) compared with the high values ensured by end-to-end (96%IBS) and modified step-cut junctions (92%IBS), taper junctions significantly increased stiffness under sagittal bending and torsion in intra- and extra-direction: end-to-end 29%IBS, 7%IBS, 7%IBS, modified step-cut 38%IBS, 20%IBS, 21%IBS, and taper junction 52%IBS, 55%IBS, 56%IBS, respectively. Construct stiffness with taper junctions was decreased by 11–41%IBS by replacing the bone plate with an intramedullary nail. Taper junctions can be an alternative to achieve intercalary reconstructions with more homogeneous and, in three out of four loading conditions, significantly higher construct stability without increasing bone plate stiffness. The risk of instability under high torsional loads increases when taper junctions are associated with a low-stiffness intramedullary nail.

Custom Massive Allograft in a Case of Pelvic Bone Tumour: Simulation of Processing with Computerised Numerical Control vs. Robotic Machining.

The use of massive bone allografts after the resection of bone tumours is still a challenging process. However, to overcome some issues related to the processing procedures and guarantee the best three-dimensional matching between donor and recipient, some tissue banks have developed a virtual tissue database based on the scanning of the available allografts for using their 3D shape during virtual surgical planning (VSP) procedures. To promote the use of future VSP bone-shaping protocols useful for machining applications within a cleanroom environment, in our work, we simulate a massive bone allograft machining with two different machines: a four-axes (computer numerical control, CNC) vs. a five-axes (robot) milling machine. The allograft design was based on a real case of allograft reconstruction after pelvic tumour resection and obtained with 3D Slicer and Rhinoceros software. Machining simulations were performed with RhinoCAM and graphically and mathematically analysed with CloudCompare and R, respectively. In this case, the geometrical differences of the allograft design are not clinically relevant; however, the mathematical analysis showed that the robot performed better than the four-axes machine. The proof-of-concept presented here paves the way towards massive bone allograft cleanroom machining. Nevertheless, further studies, such as the simulation of different types of allografts and real machining on massive bone allografts, are needed.

Mid-term outcomes of hemipelvic allograft reconstruction after pelvic bone tumor resections.

Objectives This study aims to evaluate survival of patients and implants, functions, and morbidity of surgical technique of reconstruction with a fresh-frozen massive pelvic allograft following a pelvic resection.Patients and methods Between January 2009 and December 2016, a total of 19 patients (12 males, 7 females; mean age: 35.8±14.4 years; range, 10 to 53 years) who underwent reconstruction with fresh-frozen massive allograft after internal hemipelvectomy were retrospectively analyzed. Patients̓ age, sex, resection types, histopathology and grades, surgical margins, operative times, intraoperative blood loss, complications experienced during their treatment (infection, dislocation, implant failure, nonunion, local recurrence and metastasis), neoadjuvant and adjuvant therapies they received, and functional scores were revelaed and analyzed in 10 years period.Results According to the Enneking and Dunham classification, two (10%) patients had type I resection only, six (32%) had type I-II, one (5%) had a type II resection, one (5%) had type II-III resection, three (16%) had type I-II-III resection, one (5%) had type I-IV resection, and five (26%) had type I-II-IV resection. The resection involved the acetabulum (type II) in all, but three patients. Several complications were seen in 12 patients, although seven patients had no complication. Pelvic resections had a high mortality rate in patients with malignant tumors and reconstruction with massive allograft had a high morbidity rate with susceptibility to many complications. Prolonged surgical time was found to be directly related to blood loss. Deep infection significantly worsened functional results.Conclusion Despite the high complication rates seen in pelvic resections, massive pelvic allografts represent a valid option for reconstruction after resection of pelvic tumors, but due to the associated morbidity, patients should be carefully selected.

Patient-Specific 3D-Printed Titanium Implant for Distal Tibial Critical Bone Defect

Aim: Post-traumatic large critical bone defects remain a challenge for today’s orthopedist. Despite multiple available options for treatment including autograft, massive allograft and various methods of bone transport, no strategy has shown itself to be free of significant complications or discouraging rates of nonunion and other mechanisms of failure. Case presentation: Here, we present a patient example of successful treatment of critical bone defect of the distal tibia utilizing the novel technology of a 3D-printed titanium cage coupled with a combination of autologous and allogenic bone graft in a 26-year-old male injured in motor vehicle collision. Conclusion: This case provides further evidence of a successful and promising new treatment to address these challenging injuries.

CORR Insights®: Does Local Zoledronate Applied to Pasteurized Bone Autografts Improve the Likelihood of Union of Graft-Host Junctions after Limb-sparing Surgery?

CORR Insights®: Does Local Zoledronate Applied to Pasteurized Bone Autografts Improve the Likelihood of Union of Graft-Host Junctions after Limb-sparing Surgery?

Periosteal osteosarcoma of the femur treated with modified capanna procedure: A case report.

IntroductionPeriosteal osteosarcoma is a rare type of primary bone tumor. A vascularized fibula graft incorporates this revolutionary approach with a traditional massive allograft to reconstruct large femur and tibia defects during oncological resection. A structurally competent reconstruction with improved vascular and osteogenic capacities with the ability to achieve lower rates of fracture, infection, and non-union is obtained by integrating the benefits of the separate components.MethodA 16-year-old female diagnosed with periosteal osteosarcoma of the left shaft femur. We performed neoadjuvant chemotherapy, limb salvage surgery consists of surgical resection and reconstruction, followed by adjuvant chemotherapy post operatively. We used Capanna procedure to salvage the femur.ResultPost-operative evaluation showed stable fixation clinically and radiologically. There is no complications observed during recovery, as both distal motor and sensory are normal eventhough the patient were still limited in the motion of the hip and knee at the time due to post-operative pain.DiscussionCappana procedure has been known as a novel surgical method that could decrease the risk of complications results from classic reconstruction method, such as fracture, non-union, and infection.ConclusionModified Cappana procedure which introduce the use liquid nitorgen-recycled autograft from the resected affected bone as a peripheral shell supporting a centrally placed vascularized fibular graft to fill the massive bone defect left by surgical resection, had successfully performed in our patient whom previously diagnosed with periosteal osteosarcoma of femoral shaft.

Complications mécaniques après résection et reconstruction non-prothétique des sarcomes des extrémités

BackgroundBiological reconstruction after tumor resection is significant for restoration of limb integrality. However, it is unclear what risk factors influence mechanical complications of patients after extremity sarcoma resection and biological reconstruction. The objective of study was (1) to compare complications between patients receiving inactivated autograft and allograft, (2) to analyze influence of graft type, nonunion and fixation method on mechanical complications for patients after biological reconstruction. HypothesisWe hypothesized allograft, nonunion and fixation method influence occurrence of mechanical complications after biological reconstruction. Materials and methodsWe retrospectively reviewed 71 patients with sarcomas at the extremity receiving biological reconstruction from January 1999 to November 2015. Eight patients were lost at last follow-up. Sixty-three patients with complete clinical data were recruited into the present study. There were 32 males and 31 females with a mean age of 20.5±14.9 yrs (median, 17 yrs; range, 2–72 yrs). Sixty-one cases had tumors at lower extremity and two at upper extremity. Histological diagnosis was confirmed as forty-five with osteosarcoma, thirteen with Ewing sarcoma and five with chondrosarcoma. ResultsForty-four patients were free of disease, sixteen died of disease and three lived with pulmonary metastasis at last follow-up. Twenty-one out of 63 patients (33.3%) had local recurrence requiring surgical treatment. Reconstruction choice (mechanical complications rates were 38.9% for allograft (14/36) versus 14.8% inactivated autograft (4/27)) and nonunion occurrence (yes 58.8% (10/17); no 17.4% (8/46)) had the close relationship with mechanical complication in the univariate analysis. The multivariate analysis revealed fixation method (p=0.041) and nonunion (p=0.008) were prognostic factors for mechanical complication of sarcoma resection and biological reconstruction at the extremity. Fourteen of 36 patients receiving massive allograft had a second surgery due to mechanical complication compared to 4 of 27 patients with massive inactivated autograft [38.9%, 14/36 vs. 14.8%, 4/27 (p=0.05)]. Time to union for diaphysis and metaphysis was not significantly different between allograft and inactivated autograft groups. DiscussionPatients receiving massive allograft are prone to suffer from the mechanical complications. Extramedullary plate and nonunion have the tendency of increasing occurrence of mechanical complications of biological reconstruction. Level of EvidenceIV; retrospective study.

PTH1-34 improves devitalized allogenic bone graft healing in a murine femoral critical size defect

The treatment of large segmental defects of long bones resulting from trauma, infection, or bone tumor resections is a major challenge for orthopedic surgeons. The reconstruction of bone defects with acellular allografts can be used as an osteoconductive approach. However, devitalized allografts are associated with high rates of clinical failure as a result of poor intrinsic osteoinduction properties and a lack of further remodeling. Nevertheless, evidence suggests that due to its anabolic properties, teriparatide (PTH1-34) could be effective as an adjuvant therapy for massive allograft healing. Therefore, our goal was to investigate in a murine critical-sized defect model whether the intermittent administration of PTH1-34 improves the incorporation and revitalization of acellular structural bone allografts. Thus, a 2.5-mm critical-sized defect was established in the right femur of C57BL/6 mice, followed by the reconstruction with a devitalized cortical structural allograft. A titanium micro locking plate was applied to the anterior femoral surface and secured in place with self-tapping locking screws. Subsequently, daily doses of PTH1–34 (30, and 40 µg/kg) or saline were administered to the mice for 14 days after surgery. The mice were maintained without PTH1–34 therapy for an additional 7 days before being euthanized at 3 weeks post-surgery. Bone graft consolidation was assessed on radiographic images and by histomorphometric analysis. Additionally, to determine the frequency of osteoprogenitor cells in the bone marrow and their in vitro osteogenic capacity, stromal cells were isolated from the bone marrow of animals treated with 30 or 40 µg/kg/day of PTH1-34 following the same protocol used for the experimental animals. Our results suggest that intermittent PTH1-34 treatment at 30 µg/kg/day after femoral allograft reconstruction surgery accelerated the healing process as evidenced by new bone formation induced on endosteal and periosteal surfaces, enhanced revitalization of allogeneic graft, and increased frequency and osteogenic capacity of bone marrow stromal cells (BMSC). These findings should encourage further studies aimed at investigating the potential therapeutic use of intermittent PTH1-34, specifically with regards to the optimal dosing regimen in clinically challenging orthopedic scenarios.

Use of Vascularized Fibular Epiphyseal Transfer with Massive Bone Allograft for Proximal Humeral Reconstruction in Children with Bone Sarcoma.

The vascularized fibula epiphyseal transfer provides a reconstructive option for longitudinal growth after oncologic resection of the proximal humerus in pediatric patients. However, postoperative fractures and poor shoulder function are common. The purpose of this review was to introduce a composite approach in oncologic reconstruction of the proximal humerus and assess its clinical outcomes. We retrospectively investigated five children (3 osteosarcoma and 2 Ewing's sarcoma) who underwent biological reconstruction with combination of vascularized fibula epiphyseal transfer and massive bone allograft after oncologic resection of the proximal humerus. The mean follow-up was 46.8 months. All patients were alive at the last follow-up. There was no graft fracture, hardware failure, or infection. The mean time of osseous union was 2.9 months at fibula-humerus junction and 6.2 months at allograft-humerus junction. Hypertrophy and axial growth were evident in all, except one patient who has avascular necrosis of the fibula head. The mean hypertrophy index was 51.5%, and the mean growth was 4.4 mm per annum. The mean arm discrepancy was 4.6 cm. All reconstruction was in situ with the average abduction of 113° and forward flexion of 69°. The mean Musculoskeletal Tumor Society (MSTS) score was 85.4% at the final follow-up. All patients experienced dropped foot and resolved spontaneously. The combination of vascularized fibula epiphyseal transfer with massive allograft bone provides a reliable oncologic reconstruction of proximal humerus in children. It not only offers the ability of longitudinal growth, hypertrophy, and osseous union but also diminishes reconstructive complications and improves shoulder function. Therapeutic Level IV.

Analysis of mechanical complications for patients with extremity sarcoma after biological reconstruction

BackgroundBiological reconstruction after tumor resection is significant for restoration of limb integrality. However, it is unclear what risk factors influence mechanical complications of patients after extremity sarcoma resection and biological reconstruction. The objective of study was (1) to compare complications between patients receiving inactivated autograft and allograft, (2) to analyze influence of graft type, nonunion and fixation method on mechanical complications for patients after biological reconstruction. HypothesisWe hypothesized allograft, nonunion and fixation method influence occurrence of mechanical complications after biological reconstruction. Materials and methodsWe retrospectively reviewed 71 patients with sarcomas at the extremity receiving biological reconstruction from January 1999 to November 2015. Eight patients were lost at last follow-up. Sixty-three patients with complete clinical data were recruited into the present study. There were 32 males and 31 females with a mean age of 20.5±14.9 years (median, 17 years; range, 2–72 years). Sixty-one cases had tumors at lower extremity and two at upper extremity. Histological diagnosis was confirmed as forty-five with osteosarcoma, thirteen with Ewing sarcoma and five with chondrosarcoma. ResultsForty-four patients were free of disease, sixteen died of disease and three lived with pulmonary metastasis at last follow-up. Twenty-one out of 63 patients (33.3%) had local recurrence requiring surgical treatment. Reconstruction choice (mechanical complications rates were 38.9% for allograft (14/36) versus 14.8% for inactivated autograft (4/27)) and nonunion occurrence (yes 58.8% (10/17); no 17.4% (8/46)) had the close relationship with mechanical complication in the univariate analysis. The multivariate analysis revealed fixation method (p=0.041) and nonunion (p=0.008) were prognostic factors for mechanical complication of sarcoma resection and biological reconstruction at the extremity. Fourteen of 36 patients receiving massive allograft had a second surgery due to mechanical complication compared to 4 of 27 patients with massive inactivated autograft (38.9%, 14/36 vs. 14.8%, 4/27 (p=0.05)). Time to union for diaphysis and metaphysis was not significantly different between allograft and inactivated autograft groups. DiscussionPatients receiving massive allograft are prone to suffer from the mechanical complications. Extramedullary plate and nonunion have the tendency of increasing occurrence of mechanical complications of biological reconstruction. Level of Evidence: IV; retrospective study.