Comparison of Pediatric Intercalary Allograft Reconstructions with and without a Free Vascularized Fibula:

Hip Preservation and Capanna Reconstruction for Pediatric Proximal Femur Ewing Sarcoma: A Report of 2 Cases

CASE

This is a first report describing preservation of the femoral head by transcervical resection of proximal femoral Ewing sarcoma in 2 pediatric patients. A unique Capanna reconstruction supported joint salvage. At 1 year, Pediatric Outcomes Data Collection Instrument and Pediatric Toronto Extremity Salvage Score outcomes were excellent. Surveillance magnetic resonance imaging was without evidence of recurrence or impaired perfusion to the femoral head.

CONCLUSION

We demonstrate the feasibility of hip joint preservation and maintenance of femoral head viability after transcervical resection of pediatric proximal femur bone sarcomas while preserving the medial circumflex femoral artery. This technique may be a preferred option over joint sacrifice and endoprosthetic replacement in young patients when tumor margins permit.

Comparing Fibula Flap Insetting Techniques for Pediatric Oncologic Extremity Reconstruction

BACKGROUND

Extremity reconstruction in skeletally immature patients presents unique challenges in terms of operative technique, bone healing, and limb function. A variety of insetting techniques have been described, with no clearly superior option. The authors hypothesized that vascularized fibula flaps placed in the intramedullary space are associated with shorter union times and better functionality compared with onlay flaps.

METHODS

In a cohort study, the authors retrospectively reviewed the medical records of all pediatric patients who underwent fibula flap extremity reconstruction at a single center from 2001 through 2018. Comorbidities, complications, and outcomes were analyzed. Complete fibula union was based on radiographic evidence of significant cortical bridging.

RESULTS

Thirty-three patients (mean age, 13.6 years; range, 2 to 18 years) underwent pedicled ( n = 7) or free ( n = 26) fibula flap reconstructions in 12 upper extremities and 21 lower extremities. Median follow-up was 69.5 months (interquartile range, 16.3 to 114.6 months). Onlay and intramedullary fibula position compared with intercalary placement (median, 13.5 and 14.6 months versus 3.4 months; P = 0.002) were associated with longer time to complete bone union. Complications including allograft fracture ( P = 0.02) and hardware removal ( P = 0.018) were also associated with longer time to complete union and eventual conversion to megaprosthesis ( P = 0.02, P = 0.038). Thirty-two patients (97%) achieved full union and a functional reconstruction.

CONCLUSIONS

Fibula flap reconstruction is safe and effective for pediatric long-bone reconstruction. Longer fibula union times were associated with onlay and intramedullary fibula placement, allograft fracture, and hardware removal.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Limb salvage surgery reconstructive techniques following long-bone lower limb oncological resection: a systematic review and meta-analysis

BACKGROUND

Limb salvage surgery (LSS) is now considered the gold standard surgical treatment for lower limb bone sarcomas. However, there is a paucity of literature comparing the various LSS reconstructive options. The aim of this systematic review and meta-analysis was to compare functional outcomes and complications of LSS reconstructive techniques.

METHODS

The primary aim of the meta-analysis was to determine functional outcomes from the pooled data utilizing the Musculoskeletal Tumour Society score (MSTS). Comparisons could then made for this outcome between biological and prosthetic, vascularised and non-vascularised, and prosthetic and composite reconstructions. The secondary aim was to compare complication outcomes of each reconstruction. Standardized mean difference (Cohen's d) and odds ratios were estimated using a random effects model.

RESULTS

Fourteen studies with a total of 785 patients were included. We found structural failure was 75% less likely to occur in prosthetic reconstruction compared to biological (OR = 0.24; 95% CI: 0.07-0.79; P = 0.02). We did not find any evidence of difference in function (MSTS score) between vascularised verses non-vascularised reconstructions (Cohen's d = -1.14; 95% CI = -3.06 to 0.78; I2  = 87%). Other analyses comparing complications found no difference between the reconstructive groups.

CONCLUSION

The study found no correlation between functional outcomes and the type of LSS reconstruction. Structural failure was more likely to occur in biological when compared with prosthetic reconstruction. There was no correlation between the incidence of other complications and the type of LSS technique. This suggests a role for improved approaches to reconstruction methods including bioprinting and bioresorbable devices.

Epiphyseal-sparing biological reconstruction of bone sarcoma in children: Focus on articular function and growth

INTRODUCTION

Epiphyseal preservation surgery and biological reconstruction after resection of metaphyseal bone sarcoma in children is a surgical challenge which can only be justified if future joint function is maintained.

HYPOTHESIS

The main hypothesis of this work was that long-term function was maintained. The secondary hypotheses were that local control of the disease and growth restoration were achieved, at the cost of an acceptable number of complications.

MATERIAL AND METHOD

This was a retrospective study of 14 children with a median age of 8 years [2-14] at the time of surgery. The tumors (Ewing's sarcoma or osteosarcoma) were mostly situated at the knee (n=9) and hip (n=3). The reconstruction used an induced membrane (n=7) or an allograft (n=7). We studied joint function, mechanisms contributing to loss of growth, surgical complications and survival at the last follow-up.

RESULTS

At the median follow-up of 76 months [24-130], 9 out of 14 patients required revision for non-union, and 4 of them required a second revision. At the last follow-up, 82% of the length had been restored, due to 3 bone lengthenings and 7 contralateral epiphysiodeses. Preserved joint function was excellent with an average modified MSTS score of 28.3/30 [24-30]. No local recurrence was reported.

DISCUSSION

Our experience of epiphyseal preservation allows local control of the disease and very good function but at the cost of a cumbersome surgical program (12 out of 14 patients were reoperated on, with an average of 1.2 interventions per patient). The main difficulty is the growth management, most often by complex programs of alternating bone lengthening and shortening.

LEVEL OF EVIDENCE

IV, retrospective study.

Long-Term Follow-Up of Biological Reconstruction with Free Fibular Graft after Resection of Extremity Diaphyseal Bone Tumors

This study aimed to evaluate the clinical outcomes and complications of reconstruction with a composite free fibula inside other biological grafts. We retrospectively reviewed 26 patients who underwent reconstruction after bone tumor resection of the diaphysis of the long bone. Surgical data, time to bony union, functional outcomes, and complications were evaluated in all cases. The median follow-up was 72.5 months. The limb salvage rate was 100%. Primary osseous union was achieved in 90.4% of the junctions. The union rates at the metaphyseal and diaphyseal junctions were 100% and 85.7%, respectively (p = 0.255). The mean time of bony union in the upper (87.5%) and lower (91.7%) extremity was 4.6 ± 1.6 months and 6.9 ± 2 months, respectively. The mean MSTS score was 27.2 ± 3.2, with a mean MSTS rating of 90.7%. Complications occurred in 15.4% of the cases. The administration of vascularized or non-vascularized grafts did not significantly influence the union time (p = 0.875), functional outcome (p = 0.501), or blood loss (p = 0.189), but showed differences in operation time (p = 0.012) in lower extremity reconstruction. A composite free fibula inside other biological grafts provides a reasonable and durable option for osseous oncologic reconstruction of the long bone diaphysis of the extremities with an acceptable rate of complications. A higher union rate was achieved after secondary bone grafting. In lower-extremity reconstruction, two plates may be considered a better option for internal fixation. Vascularizing the fibula did not significantly affect the union time.

Factors Influencing Nonunion and Fracture Following Biological Intercalary Reconstruction for Lower-Extremity Bone Tumors: A Systematic Review and Pooled Analysis

OBJECTIVES

To determine nonunion rate, fracture rate, and their risk factors following biological intercalary reconstruction for lower extremity bone tumors.

METHODS

A systematic review and pooled analysis were conducted. PubMed, Embase, and Wiley Cochrane Library were searched from inception up to June 01, 2020. Studies concerning biological intercalary reconstruction after resection of lower extremity bone tumors were included. Overall nonunion and fracture rates were calculated. For studies reporting patient outcomes individually with precise graft characteristics and fixation methods, the individual data were extracted. Patients with demographical and clinical characteristics, including age, sex, tumor location, graft characteristics, and fixation method, were pooled for a multivariate analysis. For each factor of interest, odds ratio (OR), 95% confidence interval (95% CI), and p-value from logistic regression were reported.

RESULTS

A total of 2776 articles were identified from the initial literature search and 76 studies (2052 patients) were included. Sixty-nine studies were case series and seven were comparative studies. The overall nonunion rate was 19% (382/2052; range: 0%-53%), and the overall fracture rate was 17% (344/2052; range: 0%-75%). Thirty of the 76 studies (362 patients) reported patients' characteristics individually and were thus included in the pooled multivariate analysis. Intramedullary nail fixation was associated with a significantly higher nonunion rate compared to plate fixation (OR = 2.2, 95% CI: 1.23-4.10, p = 0.009). Reconstruction with a vascularized fibula graft had a statistically non-significant lower nonunion rate than reconstruction without the graft (OR = 0.6, 95% CI: 0.34-1.07, p = 0.086). Devitalized autografts had a lower fracture risk than allografts (OR = 0.3, 95% CI: 0.14-0.64, p = 0.002), and males tended to have higher fracture risk than females (OR = 2.1, 95% CI: 1.00-4.44, p = 0.049).

CONCLUSIONS

Reconstruction with intramedullary nail fixation is related to an elevated risk of nonunion. Allografts and males have a higher fracture risk than devitalized autografts and females, respectively. Further high-quality comparative analyses with large sample sizes and adequate follow-up duration are needed to validate these findings.

Plate configuration for biological reconstructions of femoral intercalary defect - a finite element evaluation

BACKGROUND AND OBJECTIVE

Biological reconstruction was commonly used for femoral intercalary defect. The initial stability by plate fixation was believed to have an effect on bone union and implant failure. Our study was proposed to explore relationship of plate configuration and initial stability for femoral intercalary reconstruction using allo-/autograft.

METHODS

Femoral intercalary defect models were established with four different plate configurations: (1) Single lateral bridging plate, SLP (2) Lateral bridging plate + Orthogonal adjuvant plate, LP+OAP (3) Lateral bridging plate + Medial adjuvant plate, LP+MAP (4) Lateral bridging plate + Medial bridging plate, LP+MP. A diaphysis defect of 12 cm was simulated, and the removed native femoral bone was used as a structural allograft with the osteotomy gap of 2 mm. Models were analyzed by finite element simulations under an axial compression of 2000N and an axial moment of 10 Nm, respectively.

RESULTS

Axial load: (1) The peak von Mises stress of SLP, LP+OAP, LP+MAP, LP+MP were 993.50 MPa, 335.63 MPa, 240.03 MPa, 281.73 MPa, respectively and LP+MAP was the lowest (p < 0.01); (2) The mean displacement of SLP, LP+OAP, LP+MAP, LP+MP was 0.765, 0.130, 0.121, 0.235 mm, respectively. LP+MAP showed the best stability while SLP had a crash in the medial proximal gap; (3) The LP+MAP configuration had the most uniform stress distribution and the lowest maximum von Mises stress of 79.7 MPa within plates. Axial torsional load: (1) The peak von Mises stress of SLP, LP+OAP, LP+MAP, LP+MP were 431.66Mpa, 120.73 MPa, 72.31 MPa, 109.86 MPa, respectively; (2) The rotation angle of SLP, LP+OAP, LP+MAP, LP+MP was 4.30°, 1.35°, 1.20°, 1.57°, respectively. All of LP+OAP, LP+MAP and LP+MP showed an optimal torsional stability.

CONCLUSIONS

For femoral intercalary reconstruction using allo-/autograft fixed by plates, LP+MAP and LP+MP configurations showed superior stability in terms of axial compression and torsion load by FE simulation. A better stability was believed to be associated with higher union rate and lower hardware failure rate.

[Clinical application of three-dimensional printed osteotomy guide plate and personalized prosthesis in knee-preserving tumor resection]

OBJECTIVE

To investigate the mid-term effectiveness of three-dimensional (3D) printed osteotomy guide plate and personalized prosthesis in knee-preserving tumor resection.

METHODS

The clinical data of 12 patients who underwent knee-preserving tumor resection and reconstruction with 3D printed osteotomy guide plate and personalized prosthesis between September 2016 and October 2018 were retrospectively analyzed. There were 7 males and 5 females. The age ranged from 7 to 59 years, with a median of 44.5 years. There were 11 cases of osteosarcoma and 1 case of fibrosarcoma, all of which were Enneking grade ⅡB. The distance from the tumor to the joint surface was 5.5-8.2 cm, with an average of 6.94 cm. Incision healing, tumor recurrence, periprosthetic fracture, and aseptic loosening were observed after operation. The Musculoskeletal Tumor Society (MSTS) scoring system was used to evaluate the function of the patients, and the knee flexion range of motion was measured.

RESULTS

The 12 patients were followed up 41-66 months, with an average of 54.5 months. The length of osteotomy ranged from 14 to 26 cm, with an average of 22.08 cm. Except for 2 patients with superficial infection of incision tissue, no deep infection involving the prosthesis occurred, no patient underwent revision surgery because of prosthesis infection. During the follow-up, local recurrence occurred in 2 cases and distant metastasis occurred in 3 cases. The overall disease-free survival rate was 58.3%. Two patients died of lung metastasis, and the overall survival rate was 83.3%. One patient underwent amputation due to local recurrence, and 1 patient underwent total knee arthroplasty due to prosthesis rupture. No aseptic loosening of the prosthesis and periprosthetic fracture occurred during the follow-up, and the overall prosthesis survival rate was 83.3%. At last follow-up, 10 patients obtained satisfactory knee flexion range of motion that ranged from 95° to 125°, with an average of 110°. Two children could not cooperate with early rehabilitation treatment due to pain, and the knee flexion range of motion was not ideal (50°, 75°). All patients achieved acceptable lower limb function with MSTS scores ranged from 26 to 30, with an average of 28. All patients walked without crutches.

CONCLUSION

The treatment of malignant bone tumors around the knee joint with 3D printed osteotomy guide plate and personalized prosthesis can preserve the articular surface, obtain good limb function, reduce the risk of aseptic loosening of prosthesis, and achieve better mid-term effectiveness.

3D Customized Biological Tibial Intramedullary Nail Fixation for the Treatment of Fracture after Massive Allograft Bone Transplantation of Tibial Osteosarcoma: A Case Report

Allograft bone fractures are critical complications in massive allograft bone transplantations. There are limited studies available on the application of 3D printing for massive allograft bone transplantation complications, and no related reports on the treatment of an allograft bone fracture with a complete biological intramedullary nail. A complex case of allograft bone fracture after massive bone transplantation for a right tibial osteosarcoma was treated with fixation of an individualized 3D printed biological tibial intramedullary nail. Prior to the operation, the intramedullary nail was designed and printed based on the results of computed tomography examination of the affected limb, and the surface of the intramedullary nail was treated with a hydroxyapatite coating. Intraoperatively, the intramedullary nail was implanted according to the preoperative 3D design plan. The intraoperative and postoperative examinations showed that the 3D printed intramedullary nail achieved good matching between the implant and the medullary cavity, and the biological coating integrated well with surrounding bone. The follow-up results 44 months postoperatively showed that the patient was satisfied with the surgical results, where his ankle function met his daily needs, and the Musculoskeletal Tumor Society score was 24. 3D printing tibial intramedullary nail fixation can be successful in the treatment of allograft bone fractures and should be considered as a treatment of choice. In this case, the intramedullary nail matched the surrounding bone well, had good osseointegration, and the patient regained basic function.

Hip-Preserved Reconstruction Using a Customized Cementless Intercalary Endoprosthesis With an Intra-Neck Curved Stem in Patients With an Ultrashort Proximal Femur: Midterm Follow-Up Outcomes

Background: Hemiarthroplasty is widely used for proximal femoral reconstruction after tumor resection. However, complications of hemiarthroplasty include infection, hip dislocation, and acetabular wear. This study aimed to: (1) evaluate the reliability and validity of a customized cementless intercalary endoprosthesis (CCIE) with an intra-neck curved stem (INCS) to reconstruct femoral diaphyseal defects with an ultrashort proximal femur (UPF); (2) assess the lower extremity function after reconstruction with this endoprosthesis; and (3) identify the postoperative complications associated with the use of this endoprosthesis.

Methods: Between October 2015 and May 2019, 13 patients underwent reconstruction with a CCIE with an INCS. The distance from the center of the femoral head to the midline of the body and the apex of the acetabulum was measured preoperatively. Additionally, the distance from the tip of the INCS to the midline of the body and the apex of the acetabulum was measured postoperatively. The femoral neck–shaft angle was also measured pre- and postoperatively. After an average follow-up duration of 46 months, the radiological outcomes of the CCIE with an INCS were analyzed. Function was evaluated with the Musculoskeletal Tumor Society (MSTS) score. Pain was measured using a paper visual analog scale (VAS) pre- and postoperatively, and complications were recorded.

Results: Compared with our preoperative design, we found no significant difference in the postoperative distance from the tip of the INCS to the body midline (p = 0.187) and the apex of the acetabulum (p = 0.159), or in the postoperative femoral neck–shaft angle (p = 0.793). Thus, the INCS positions were deemed accurate. The average MSTS score was 26 (range: 24–28), and the VAS score was significantly decreased postoperatively compared with preoperatively (p < 0.0001). No patients developed aseptic loosening, infection, periprosthetic fracture, or prosthetic fracture as of the last follow-up.

Conclusion: The CCIE with an INCS was a valid and reliable method for reconstructing femoral diaphyseal defects with a UPF following malignant tumor resection. Postoperative lower extremity function was acceptable, with an appropriate individualized rehabilitation program, and the incidence of complications was low.

Free Vascularized Fibula Flap Reconstruction of Total and Near-total Destabilizing Resections of the Sacrum

BACKGROUND

Vascularized bone grafts (VBGs) are associated with improved union and fewer instrumentation complications in the mobile spine. It is not known if VBGs are similarly efficacious after sacrectomy.

METHODS

We conducted a retrospective chart review of all patients who underwent total sacrectomy and immediate reconstruction with VBG between 2005 and 2019. Patient and surgical characteristics in addition to union and functional outcomes were analyzed.

RESULTS

We identified 10 patients (6 women and 4 men) with a mean age of 42 years (range, 12-71 years). All patients received iliolumbar instrumentation as well as a free fibula flap as a VBG. There were no complications at the fibula flap donor site or specifically related to the VBG. Bony union was achieved in 7 (88%) of 8 patients with an average union time of 6.3 months (range, 2-10 months). Surgical complications occurred in 5 patients, 4 patients required reoperation for wound dehiscence, and 1 patient required conversion to a 4-rod construct and bone grafting for instrumentation loosening and partial nonunion. Instrumentation failure developed in 1 patient, but no surgical intervention was required. One patient was able to walk independently without any limitation, 5 patients required a walker, 2 were wheelchair-bound except for short (<15 ft) distances, and 2 were lost to follow-up.

CONCLUSIONS

The free vascularized fibula flap is a safe and effective option for supplementing spinal reconstruction after destabilizing sacrectomy.

Does the Addition of a Vascularized Fibula Improve the Results of a Massive Bone Allograft Alone for Intercalary Femur Reconstruction of Malignant Bone Tumors in Children?

BACKGROUND

Massive bone allograft with or without a vascularized fibula is a potentially useful approach for femoral intercalary reconstruction after resection of bone sarcomas in children. However, inadequate data exist regarding whether it is preferable to use a massive bone allograft alone or a massive bone allograft combined with a vascularized free fibula for intercalary reconstructions of the femur after intercalary femur resections in children. Because the addition of a vascularized fibula adds to the time and complexity of the procedure, understanding more about whether it reduces complications and improves the function of patients who undergo these resections and reconstructions would be valuable for patients and treating physicians.

QUESTIONS/PURPOSES

In an analysis of children with bone sarcomas of the femur who underwent an intercalary resection and reconstruction with massive bone allograft with or without a vascularized free fibula, we asked: (1) What was the difference in the surgical time of these two different surgical techniques? (2) What are the complications and number of reoperations associated with each procedure? (3) What were the Musculoskeletal Tumor Society scores after these reconstructions? (4) What was the survival rate of these two different reconstructions?

METHODS

Between 1994 and 2016, we treated 285 patients younger than 16 years with a diagnosis of osteosarcoma or Ewing sarcoma of the femur. In all, 179 underwent resection and reconstruction of the distal femur and 36 patients underwent resection and reconstruction of the proximal femur. Additionally, in 70 patients with diaphyseal tumors, we performed total femur reconstruction in four patients, amputation in five, and a rotationplasty in one. The remaining 60 patients with diaphyseal tumors underwent intercalary resection and reconstruction with massive bone allograft with or without vascularized free fibula. The decision to use a massive bone allograft with or without a vascularized free fibula was probably influenced by tumor size, with the indication to use the vascularized free fibula in longer reconstructions. Twenty-seven patients underwent a femur reconstruction with massive bone allograft and vascularized free fibula, and 33 patients received massive bone allograft alone. In the group with massive bone allograft and vascularized fibula, two patients were excluded because they did not have the minimum data for the analysis. In the group with massive bone allograft alone, 12 patients were excluded: one patient was lost to follow-up before 2 years, five patients died before 2 years of follow-up, and six patients did not have the minimum data for the analysis. We analyzed the remaining 46 children with sarcoma of the femur treated with intercalary resection and biological reconstruction. Twenty-five patients underwent femur reconstruction with a massive bone allograft and vascularized free fibula, and 21 patients had reconstruction with a massive bone allograft alone. In the group of children treated with massive bone allograft and vascularized free fibula, there were 17 boys and eight girls, with a mean ± SD age of 11 ± 3 years. The diagnosis was osteosarcoma in 14 patients and Ewing sarcoma in 11. The mean length of resection was 18 ± 5 cm. The mean follow-up was 117 ± 61 months. In the group of children treated with massive bone allograft alone, there were 13 boys and eight girls, with a mean ± SD age of 12 ± 2 years. The diagnosis was osteosarcoma in 17 patients and Ewing sarcoma in four. The mean length of resection was 15 ± 4 cm. The mean follow-up was 130 ± 56 months. Some patients finished clinical and radiological checks as the follow-up exceeded 10 years. In the group with massive bone allograft and vascularized free fibula, four patients had a follow-up of 10, 12, 13, and 18 years, respectively, while in the group with massive bone allograft alone, five patients had a follow-up of 10 years, one patient had a follow-up of 11 years, and another had 13 years of follow-up. In general, there were no important differences between the groups in terms of age (mean difference 0.88 [95% CI -0.6 to 2.3]; p = 0.26), gender (p = 0.66), diagnosis (p = 0.11), and follow up (mean difference 12.9 [95% CI-22.7 to 48.62]; p = 0.46). There was a difference between groups regarding the length of the resection, which was greater in patients treated with a massive bone allograft and vascularized free fibula (18 ± 5 cm) than in those treated with a massive bone allograft alone (15 ± 4 cm) (mean difference -3.09 [95% CI -5.7 to -0.4]; p = 0.02). Complications related to the procedure like infection, neurovascular compromise, and graft-related complication, such as fracture and nonunion of massive bone allograft or vascularized free fibula and implant breakage, were analyzed by chart review of these patients by an orthopaedic surgeon with experience in musculoskeletal oncology. Survival of the reconstructions that had no graft or implant replacement was the endpoint. The Kaplan-Meier test was performed for a survival analysis of the reconstruction. A p value less than 0.05 was considered significant.

RESULTS

The surgery was longer in patients treated with a massive bone allograft and vascularized free fibula than in patients treated with a massive bone allograft alone (10 ± 0.09 and 4 ± 0.77 hours, respectively; mean difference -6.8 [95% CI -7.1 to -6.4]; p = 0.001). Twelve of 25 patients treated with massive bone allograft and vascularized free fibula had one or more complication: allograft fracture (seven), nonunion (four), and infection (four). Twelve of 21 patients treated with massive bone allograft alone had the following complications: allograft fracture (five), nonunion (six), and infection (one). The mean functional results were 26 ± 4 in patients with a massive bone allograft and vascularized free fibula and 27 ± 2 in patients with a massive bone allograft alone (mean difference 0.75 [95% CI -10.6 to 2.57]; p = 0.39). With the numbers we had, we could not detect a difference in survival of the reconstruction between patients with a massive bone allograft and free vascularized fibula and those with a massive bone allograft alone (84% [95% CI 75% to 93%] and 87% [95% CI 80% to 94%], respectively; p = 0.89).

CONCLUSION

We found no difference in the survival of reconstructions between patients treated with a massive bone allograft and vascularized free fibula and patients who underwent reconstruction with a massive bone allograft alone. Based on this experience, our belief is that we should reconstruct these femoral intercalary defects with an allograft alone and use a vascularized fibula to salvage the allograft only if a fracture or nonunion occurs. This approach would have resulted in about half of the patients we treated not undergoing the more invasive, difficult, and risky vascularized procedure.Level of Evidence Level III, therapeutic study.

Intercalary reconstruction following resection of diaphyseal bone tumors: A systematic review

INTRODUCTION

The options for the reconstruction of diaphyseal defects following the resection of bone tumors include biological or prosthetic implants. The purpose of our study was to evaluate different types of intercalary reconstruction techniques, including massive bone allograft, extracorporeal devitalized autograft, vascularized free fibula, and modular prosthesis.

METHODS

We performed a systematic review of articles using the terms diaphyseal bone tumor and intercalary reconstruction. All the studies reporting the non-oncological complications such as infection, nonunion and fracture of the intercalary reconstructions were included. We excluded articles published before 2000 or did not involve humans in the study. Case reports, reviews, technique notes and opinion articles were also excluded based on the abstracts. Thirty-three articles included in this review were then studied to evaluate failure rates, complications and functional outcome of different surgical intercalary reconstruction techniques.

RESULTS

Nonunion rates of allograft ranged 6%-43%, while aseptic loosening rates of modular prosthesis ranged 0%-33%. Nonunion rates of allograft alone and allograft with a vascularized fibula graft ranged 6%-43% and 0%-33%, respectively. Fracture rates of allograft alone and allograft with a vascularized fibula graft ranged 7%-45% and 0%-44%, respectively. Infection rates of allograft alone and allograft with a vascularized fibula graft ranged 0%-28% and 0%-17%, respectively. All of the allograft (range: 67%-92%), extracorporeal devitalized autograft including irradiation (87%), autoclaving (70%), pasteurization (88%), low-heat (90%) or freezing with liquid nitrogen (90%), and modular prosthesis (range: 77%-93%) had similar Musculoskeletal Tumor Society functional scores. Addition of a vascularized fibula graft to allograft did not affect functional outcome [allograft with a vascularized fibula graft (range: 86%-94%) vs. allograft alone (range: 67%-92%)].

CONCLUSION

Aseptic loosening rates of modular prosthesis seem to be less than nonunion rates of allograft. Adding a vascularized fibula graft to allograft seems to increase bone union rate and reduce the risk of fractures and infections, though a vascularized fibula graft needs longer surgical time and has the disadvantage of donor site morbidity. These various intercalary reconstruction techniques with or without a vascularized fibula autograft had similar functional outcome.

Effects of VEGF on Prefabricated Vascularized Bone Allografts in Rats

BACKGROUND

 Massive bone defects after wide resection of malignant bone tumors or a serious injury require treatment using vascularized bone grafts. Although cadaveric bone allografts combined with vascularized bone autografts are currently thought to be ideal in terms of size and durability, this treatment requires the scarification of healthy bone tissue. In a previous study, we attempted to improve this situation by prefabricating a vascularized bone allograft in recipient rats. In this study, we added vascular endothelial growth factor (VEGF)-containing hydroxyapatite/collagen composite (HAp/Col) to a prefabricated vascularized bone allograft to stimulate angiogenesis, which is known to be important for bone formation.

METHODS

 Sprague Dawley rats (n = 50) were used as donors and Wistar rats (n = 50) as recipients. All rats were 9 weeks old. The recipient rats were divided into five groups according to the use of vascular bundles, HAp/Col, and an additive substance (VEGF). The bone allografts collected from the donors were transplanted into the thigh region of the recipients, and a saphenous vein and 10 μg HAp/Col with VEGF were inserted into the bone allografts through the slit. After 4 weeks, the transplanted bone allografts were harvested, and histologic and genetic evaluations were performed in relation to bone formation and resorption.

RESULTS

 The results showed that, compared with the control group, the implantation of the vascular bundles and VEGF-containing HAp/Col significantly stimulated angiogenesis and bone formation in the rats with the bone allografts. However, histological and genetic evaluations of bone resorption revealed that resorption was not observed in any group.

CONCLUSION

 These results suggest that VEGF-containing HAp/Col effectively stimulates angiogenesis and bone formation, but not bone resorption, in prefabricated vascularized bone allografts. This method could therefore become a useful tool for treating large bone defects.

Intercalary Allograft Reconstruction of the Proximal Tibia With and Without a Free Fibula Flap in Pediatric Patients

BACKGROUND

Limb salvage of the proximal tibia can be difficult due to the growth potential of and functional demands of the pediatric patients. Multiple reconstruction techniques exist, however, the ideal form of reconstruction is yet to be elucidated. The purpose of the current study is to evaluate outcomes in patients with an intercalary resection of the proximal tibia reconstructed with an allograft with or without a free vascularized fibula flap (FVF).

METHODS

Seventeen pediatric patients (9 males, 8 females) underwent lower extremity limb salvage with the use of intercalary cadaveric allograft at a mean age of 12±4 years. The most common diagnoses were osteosarcoma (n=6) and Ewing sarcoma (n=6). Patients were reconstructed with an allograft alone (n=6) or supplemented with an FVF (n=11).

RESULTS

All surviving patients had at least 2 years of clinical follow-up, with the mean follow-up of 12±7 years. The mean time to union of the allograft was 11±4 months, with 6 patients requiring additional bone grafting. There was no difference in the need for an additional bone graft (odds ratio=1.14, P=1.0) between patients with an FVF and those without. Four patients underwent an amputation, all with an allograft alone, due to disease recurrence (n=2) and due to infection (n=2). As such, there was a higher 10-year overall limb-salvage rate when the allograft was combined with an FVF compared with an allograft alone (100% vs. 33%, P=0.001). At last follow-up, the mean Mankin and Musculoskeletal Tumor Society rating was 86%, with a higher mean score in patients reconstructed with an FVF (94% vs. 70%, P=0.002).

CONCLUSION

Use of an intercalary allograft supplemented with an FVF to reconstruct the proximal tibia provides a durable means of reconstruction with an excellent functional outcome following oncologic proximal tibia resection in a pediatric population.

LEVEL OF EVIDENCE

Level III-therapeutic level.

Reconstruction of Large Bone Defects and Complex Non-Unions Using a Free Fibular Bone Graft and a Supplementary Allograft

Large bone defects or complex pseudarthrosis represent an interdisciplinary challenge. Established surgical procedures include autogenous cancellous bone graft, the Masquelet technique or bone transfer via segment transport as well as free microvascular bone transplantation. However, the successful use of all these techniques requires a specialized center with great interdisciplinary expertise. In the following case series we describe the technique of free fibula transplantation and additional allograft. In both cases a good functional result with full mechanical strength of the affected extremity and satisfactory patient comfort has been achieved. In the second case, implant failure with the necessity of revision endoprosthetics occurred during the procedure.

Is frozen tumour-bearing autograft with concurrent vascularized fibula an alternative to the Capanna technique for the intercalary reconstruction after resection of osteosarcoma in the lower limb?

AIMS

The use of frozen tumour-bearing autograft combined with a vascularized fibular graft (VFG) represents a new technique for biological reconstruction of massive bone defect. We have compared the clinical outcomes between this technique and Capanna reconstruction.

METHODS

From June 2011 to January 2016 a retrospective study was carried out of patients with primary osteosarcoma of lower limbs who underwent combined biological intercalary reconstruction. Patients were categorized into two groups based on the reconstructive technique: frozen tumour-bearing autograft combined with concurrent VFG (Group 1) and the Capanna method (Group 2). Demographics, operating procedures, oncological outcomes, graft union, limb function, and postoperative complications were compared.

RESULTS

A total of 23 patients were identified for analysis: eight in Group 1 and 15 in Group 2. There was no difference in the demographics (age, sex, and affected site) and operating procedures (resection length, duration of surgery, and blood loss) between the two groups. No significant difference was found in local recurrence in Group 1 versus Group 2 (p = 0.585). Mean union time for the frozen autograft-host junction was 8.4 months (7.0 to 11.0), significantly earlier than for the allograft-host junction in Group 2 (mean 14.1 months (10.0 to 28.0); p < 0.001). Mean Musculoskeletal Tumor Society scores in groups 1 and 2 were 90.3% (SD 7.4%) and 88.0% (SD 9.0%), respectively, with no significant statistical difference (p = 0.535). In terms of complications, infection (n = 1, 6.7%) and delayed union (n = 2, 13.3%) occurred in Group 2, but no such complications were observed in Group 1.

CONCLUSION

Frozen tumour-bearing autograft in combination with VFG can be used as an alternative to the Capanna reconstruction in properly selected patients with osteosarcoma. Cite this article: Bone Joint J 2020;102-B(5):646-652.

Individual Tissue-Engineered Bone in Repairing Bone Defects: A 10-Year Follow-Up Study

Bone defects caused by various causes remain a major problem in orthopedic clinics. A number of different treatments have been developed and proposed, but until now, none has proven to be completely satisfactory. For 26 patients with bone defects but limited autologous bone source or allogeneic bone graft failure, we used individual tissue-engineered bones (iTEBs) for repairing, which were constructed by autologous bone marrow mesenchymal stem cells and allogenic decalcified bone matrix (DBM) scaffolds. The clinical outcomes, including efficacy and safety, were evaluated by radiological examinations, postoperative function recovery score and laboratory tests. Twenty-six patients, including 18 men and 8 women, were followed up for an average of 10 years to analyze the long-term outcome. The mean healing time for patients with lacunar bone defects was 3.87 ± 2.01 months (range, 2-9 months) and that for structural bone defects was longer than 12 months. The Musculoskeletal Tumor Society functional evaluation system and the Barthel Index scores were significantly improved during the long-term follow-up. The white blood cell, erythrocyte sedimentation rate, C reactive protein, complement, immunoglobulins, and liver and renal functions were not significantly affected by bone grafting. One patient with bone cyst relapsed at 3 years postoperatively and achieved bone healing after re-transplantation. No tumorigenesis, tumor metastasis, or blood transmissible disease was found in the whole process. The results demonstrated that iTEBs were effective and safe for repairing bone defects in the long period, especially for those with lacunar bone defects and limited autograft source. Impact statement Currently, controversies exist about the long-term safety and effectiveness of the clinical application of tissue-engineered bones (TEBs) due to potential tumorigenesis, immune rejection, disease transmission, and others. In this study, we show that individual TEBs constructed by autologous MSCs and allogenic decalcified bone matrix are reliable for repairing bone defects in regard to its long-term safety and effectiveness. Our study provides experience and basis about the clinical application of TEBs in the treatment of bone defects.

Three-dimensional-printed intercalary prosthesis for the reconstruction of large bone defect after joint-preserving tumor resection

BACKGROUND

Joint-preserving intercalary tumor resection can result in better proprioception and a more normal joint function after reconstruction. However, most reported reconstruction techniques are usually associated with frequent complications. Therefore, the approach of reconstruction following joint-preserving tumor resection warrants further study.

METHODS

Between September 2016 and October 2018, 12 patients with metaphyseal malignant bone tumors around the knee joint were treated by joint-preserving intercalary resections with the aid of three-dimensional (3D)-printed osteotomy guide plates and reconstructions using 3D-printed intercalary prostheses. We assessed the accuracy of the resection by comparing the cross sections at the resection plane with 3D-printed matching surface of the prostheses. The functional outcomes, complications and oncological status were also evaluated.

RESULTS

All patients were observed for 7 to 32 months with an average follow-up of 22.5 months. The achieved resection was accurate, with accurate matching between the residual bone and prosthesis. The mean MSTS score was 28 (range, 26-30). Superficial infection occurred in two patients. Local recurrence was observed in one patient, while pulmonary metastasis was identified in one patient.

CONCLUSIONS

The personalized osteotomy guide plate and prosthesis based on 3D printing technique facilitate joint-preserving tumor resection and functional reconstruction. However, longer follow-up and larger sample size are required to clarify its long-term outcomes.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Ipsilateral rotational double-barrel fibula autograft for limb salvage in a pediatric patient with lower extremity intramedullary osteosarcoma: A case report

Osteosarcoma is a relatively uncommon diagnosis that often requires limb salvage techniques in young patients. Due to the potential long-life expectancy of these patients, techniques which avoid prostheses are preferred to limit the need for future revision surgeries. This case report presents a 9-year-old male diagnosed with intramedullary well-differentiated osteosarcoma of the tibial diaphysis. This limb salvage procedure utilized a rotational ipsilateral vascularized double barrel fibula autograft measuring a total of 24.5 cm when harvested but osteotomized to lengths of 11 and 12.5 cm limbs to reconstruct an 11 cm tibial shaft defect. Anterior chamfer cuts were performed on one limb allowing it to be inserted intramedullary while the second limb was then placed with an inlay technique posterolaterally and then compressed with a carbon fiber plate. The patient recovered well initially postoperatively but was taken back for revision of the carbon fiber plate 10 weeks postoperatively secondary to asymptomatic loosening of the proximal screws. The patient subsequently healed and experienced full graft incorporation with expected hypertrophy of the graft. At most recent follow-up at 19 months, the patient reported no pain and was utilizing the extremity in a normal fashion with no activity limitations. In this report, we present a case of the use of an ipsilateral rotational double-barrel fibula autograft for limb salvage in a pediatric patient with lower extremity intramedullary osteosarcoma.

Outcome of segmental prosthesis reconstruction for diaphyseal bone tumors: a multi-center retrospective study

Background

The optimal reconstructive method after diaphyseal malignant bone tumor resection remains controversial. This multicenter clinical study was designed to investigate the clinical value and complications of segmental prosthesis in the repair of diaphyseal defects.

Methods

We present 49 patients from three clinical centers treated with wide resection for primary or metastatic bone tumors involving the diaphysis of the femur, tibia, humerus, or ulna, followed by reconstruction using a modular intramedullary segmental prosthesis.

Results

Enrolled patients included 23 men and 26 women with a mean age of 63.3 years. Of these, seven patients had primary bone tumors and 42 patients had metastatic lesions. At the mean follow-up of 13.7 months, 17 patients were alive, 31 patients were deceased due to tumor progression, and one patient was dead of another reason. There were eight nononcologic complications (two with radial nerve injury, three with delayed incision healing, two with aseptic loosening in the proximal humerus prosthetic stem and one with structural failure) and three oncologic complications (three with primary tumor recurrence) among all patients. The incidence of complications in primary tumor patients (4/7, 57.1%) was higher than that in patients with metastatic tumors (7/42, 16.7%) (p = 0.036). Aseptic loosening and mechanical complications were not common for patients with primary tumors, although the reconstruction length difference was statistically significant (p = 0.023). No statistically significant differences were observed in limb function, while the mean musculoskeletal tumor society score was 21.2 in femora, 19.6 in humeri, and 17.8 in tibiae (p = 0.134).

Conclusions

Segmental prostheses represent an optional method for the reconstruction of diaphyseal defects in patients with limited life expectancy. Segmental prostheses in the humerus experienced more complications than those used to treat lesions in the femur.