The Use of ECMO and Free-Fillet-Leg Flap for Complex Pelvic Reconstruction: A Case Report.

Advanced sarcoma treatment in complex anatomical regions such as the pelvis poses significant surgical challenges. This report details a case involving a 35-year-old man with recurrent osteosarcoma of the left hemipelvis, who underwent a 16 h surgery for hemipelvectomy and reconstruction using a free tibia and fibula fillet leg flap. The procedure, necessitated by an infected, exposed iliac prosthesis, utilized extracorporeal membrane oxygenation (ECMO) for 8 h to maintain flap viability. The flap, incorporating tibia, fibula, and associated musculature was successfully inset and anastomosed to the left common iliac artery and vein, with additional venous anastomosis to the right iliac vein. Despite postoperative challenges such as venous stasis and intestinal ischemia, necessitating further surgical interventions, the patient achieved mobility with a walker at 3 months post-surgery, with stable conditions observed during a 2 years follow-up. ECMO enabled successful preservation and integration of the free fillet leg flap, demonstrating its potential in complex reconstructive surgeries. Specifically, ECMO may extend free flap viability in complex cases, offering new possibilities for challenging oncological and reconstructive surgeries.

Does adding sacroiliac (type IV) resection to periacetabular (type II) resection increase complications or provide worse clinical outcomes? An institutional experience and systematic review.

BACKGROUND AND OBJECTIVES: Internal hemipelvectomy is a limb sparing procedure most commonly indicated for malignant bone and soft tissue tumors of the pelvis. Partial resection and pelvic reconstruction may be challenging for orthopedic oncologists due to late presentation, high tumor burden, and complex anatomy. Specifically, wide resection of tumors involving the periacetabular and sacroiliac (SI) regions may compromise adjacent vital neurovascular structures, impair wound healing, or limit functional recovery. We aimed to present a series of patients treated at our institution who underwent periacetabular internal hemipelvectomy (Type II) with or without sacral extension (Type IV) in combination with a systematic review to investigate postoperative complications, functional outcomes, and implant and patient survival following pelvic tumor resection via Type II hemipelvectomy with or without Type IV resection. MATERIALS AND METHODS: A surgical registry of consecutive patients treated with internal hemipelvectomy for primary or secondary pelvic bone tumors at our institution since 1994 was retrospectively reviewed. All type II resection patients were stratified into two separate cohorts, based on whether or not periacetabular resection was extended beyond the SI joint to include the sacrum (Type IV), as per the Enneking and Dunham classification. Patient demographics, operative parameters, complications, and oncological outcomes were collected. Categorical and continuous variables were compared with Pearson's chi square or Fisher's exact test and the Mann-Whitney U test, respectively. Literature review according to PRISMA guidelines queried studies pertaining to patient outcomes following periacetabular internal hemipelvectomy. The search strategy included combinations of the key words "internal hemipelvectomy", "pelvic reconstruction", "pelvic tumor", and "limb salvage". Pooled data was compared using Pearson's chi square. Statistical significance was established as p < 0.05. RESULTS: A total of 76 patients were treated at our institution with internal hemipelvectomy for pelvic tumor resection, of whom 21 had periacetabular resection. Fifteen patients underwent Type II resection without Type IV involvement, whereas six patients had combined Type II/IV resection. There were no significant differences between groups in operative time, blood loss, complications, local recurrence, postoperative metastasis, or disease mortality. Systematic review yielded 69 studies comprising 929 patients who underwent internal hemipelvectomy with acetabular resection. Of these, 906 (97.5 %) had only Type II resection while 23 (2.5 %) had concomitant Type II/IV resection. While overall complication rates were comparable, Type II resection alone produced significantly fewer neurological complications when compared to Type II resection with sacral extension (3.9 % vs. 17.4 %, p = 0.001). No significant differences were found between rates of wound complications, infections, or construct failures. Local recurrence, postoperative metastasis, and survival outcomes were similar. Type II internal hemipelvectomy without Type IV resection on average produced higher postoperative MSTS functional scores than with Type IV resection. CONCLUSION: In our series, the two groups exhibited no differences. From the systematic review, operative parameters, local recurrence or systemic metastasis, implant survival, and disease mortality were comparable in patients undergoing Type II internal hemipelvectomy alone compared to patients undergoing some combination of Type II/IV resection. However, compound resections increased the risk of neurological complications and experienced poorer MSTS functional scores.

[Comparison of the posterior hemipelvectomy of the greater trochanter approach with the standard Kocher-Langenbeck approach in the treatment of posterior acetabulum wall fractures].

OBJECTIVE: To compare the clinical efficacy of the posterior hemipelvectomy of the greater trochanter approach with the standard Kocher-Langenbeck(K-L) approach in the treatment of posterior acetabulum wall fractures and to explore a more optimal approach for the treatment of posterior acetabulum wall fractures. METHODS: Total of 26 patients with posterior acetabulum wall fractures were retrospectively analysed and divided into two groups:the posterior hemipelvectomy of the greater trochanter group (test group) and the standard K-L approach group (control group). In the test group, there were 24 patients including 16 males and 8 females with an average age of (42.00±4.52) years old, the time of injury to surgery was (6.75±1.15) d. In the control group, there were 23 patients including 16 males and 7 females with an average age of (41.00±5.82) years old, the time of injury to surgery was (7.09±1.20) days. The total hospital stay, length of incision, operation time, intraoperative bleeding, postoperative drainage, discharge, fracture reduction quality (Matta criteria), hip abduction muscle strength, hip function (Merle d'Aubigne-Postel score), postoperative complications and the incidence of ectopic ossification were compared. RESULTS: All cases were followed up for 6 months. There was no significant difference in incision length, intraoperative bleeding and postoperative drainage between two groups(P>0.05). However, the operation time of the test group was shorter than that of the control group (P<0.05). There was no statistically significant difference in fracture reduction and hip function between two groups (P>0.05). The hip abduction muscle strength of test group was better than that of control group(P<0.05). In addition, there was no significant difference in the incidence of postoperative complications and heterotopic ossification between two groups(P>0.05). CONCLUSION: Compared with the standard K-L approach, the posterior hemipelvectomy of the greater trochanter approach can shorten the operative time, has better recovery of the postoperative hip abduction muscle strength, exposes the view of the fracture involving the more comminuted posterior acetabulum wall or the fracture of the roof of the socket, improved the rate of fracture anatomical repositioning, provides a new idea for the clinical treatment of posterior acetabulum wall fractures, and allows patients to perform functional exercises at an early stage.

[Traumatic hemipelvectomy : An uncommon case in trauma surgery]. / Traumatische Hemipelvektomie : Ein nichtalltäglicher Fall in der Unfallchirurgie.

The challenge in treating traumatic hemipelvectomy is the dynamics of the complex and life-threatening consequences of the injury. These include skin and soft tissue defects, osseous, neural and vascular injuries as well as the subsequent hemostatic derangement and organ dysfunction as part of the shock process. The treatment requires rapid and targeted decisions to save the patient's life. In this particular case a 34-year-old farmer was trapped between a wheeled loader and a stationary trailer. Upon arrival at the hospital the patient was in a state of hemorrhagic shock with accompanying acute traumatic coagulopathy and a grade III open pelvic trauma with complete ischemia of the left leg and a bladder injury. After performing emergency surgery and a two-stage approach for pelvic stabilization the patient's condition deteriorated up to multiorgan failure, necessitating left-sided hemipelvectomy as an immediate life-saving salvage procedure. In the further course multiple revision surgeries and plastic reconstructions due to wound infections and the presence of skin and soft tissue damage were required. Due to the rare confrontation with this type of injury in everyday practice and the absence of a universal treatment algorithm, the following case report is intended to contribute to a better understanding of the treatment and to illustrate the coherent interactions of the individual organ systems affected.

Limb salvage in traumatic hemipelvectomy: case series with surgical management and review of the literature.

BACKGROUND: Traumatic hemipelvectomies are rare and serious injuries. The surgical management was described in several case studies, with primary amputation often performed to save the patient's life. METHODS: We report of two survivors with complete traumatic hemipelvectomy resulting in ischemia and paralyzed lower extremity. Due to modern emergency medicine and reconstructive surgery, limb salvage could be attained. Long-term outcome with quality of life was assessed one year after the initial accident. RESULTS AND CONCLUSIONS: The patients were able to mobilize themselves and live an independent life. The extremities remained without function and sensation. Urinary continence and sexual function were present and the colostomy could be relocated in both patients. Both patients support limb salvage, even having difficulties and follow-up treatments. Concomitant cases are required to consolidate the findings. LEVEL OF EVIDENCE: IV.

Internal Hemipelvectomy for primary bone sarcomas using intraoperative patient specific instruments- the next step in limb salvage concept.

BACKGROUND: During pelvic Sarcoma resections, Surgeons often struggle to obtain negative margins while minimizing collateral damage and maintaining limb function. These complications are usually due to the complex anatomy of the pelvis. Here we present an accurate 3D surgical approach, including pre-operative printing of models and intraoperative patient-specific instruments (PSIs) for optimizing pelvic sarcoma resections. METHODS: This single-center retrospective study (N = 11) presents surgical, functional, and oncological outcomes of patients (average age 14.6 +/- 7.6 years, 4 males) who underwent pelvic sarcoma resections using a 3D surgical approach between 2016 and 2021. All patients were followed up for at least 24 months (mean = 38.9 +/- 30.1 months). RESULTS: Our results show promising surgical, oncological, and functional outcomes. Using a 3D approach, 90.9% had negative margins, and 63.6% did not require reconstruction surgery. The average estimated blood loss was 895.45 ± 540.12 cc, and the average surgery time was 3:38 ± 0.05 hours. Our results revealed no long-term complications. Three patients suffered from short-term complications of superficial wound infections. At 24 month follow up 72.7% of patients displayed no evidence of disease. The average Musculoskeletal Tumor Society (MSTS) score at 12 months was 22.81. CONCLUSION: 3D technology enables improved accuracy in tumor resections, allowing for less invasive procedures and tailored reconstruction surgeries, potentially leading to better outcomes in function and morbidity. We believe that this approach will enhance treatments and ease prognosis for patients diagnosed with pelvic sarcoma and will become the standard of care in the future.

Tratamiento multidisciplinario de condrosarcoma gigante de fémur proximal mediante hemipelvectomía externa y reconstrucción con colgajo pediculado tipo fillet flap: presentación de un caso clínico / Multidisciplinary treatment of giant chondrosarcoma of the proximal femur by external hemipelvectomy and reconstruction with a pedunculated fillet flap: presentation of a clinical case / Tratamento multidisciplinar do condrossarcoma gigante do fêmur proximal por hemipelvectomia externa e reconstrução com retalho fillet flap: apresentação de um caso clínico

El condrosarcoma forma parte de los tumores primarios malignos más frecuentes. Las localizaciones pélvicas y de raíz de muslo requerirán abordajes amplios con la consecuente dificultad de cobertura de partes blandas. La hemipelvectomía externa es habitualmente el procedimiento de elección para estas localizaciones. Implica la resección de la extremidad inferior en bloque asociada a la hemipelvis ipsilateral, dando como resultado un gran defecto de cobertura. En algunas circunstancias, la extensa resección de partes blandas hace imposible la utilización de colgajos rotacionales locales. La reconstrucción con colgajo tipo "Fillet flaps" ofrece a estos defectos de partes blandas la opción de lograr una adecuada cobertura. El objetivo del trabajo es mostrar la resolución de un caso poco convencional de condrosarcoma de fémur proximal y su reconstrucción de partes blandas con un método nunca antes utilizado en nuestro medio.

Chondrosarcoma is one of the most frequent malignant primary tumors. Pelvic and proximal femur locations require extensive approaches with the consequent difficulty of soft tissue reconstruction. External hemipelvectomy is usually the procedure for these locations. It involves total en bloc resection of the lower extremity associated with ipsilateral hemipelvis, resulting in a large coverage defect. In some cases, local rotational flaps are impossible. Reconstruction with fillet flaps offers an adequate coverage for soft tissue defects. The objective of this study is to show the resolution of an unconventional case of chondrosarcoma of the proximal femur and its soft tissue reconstruction with a method never before used in our country.

O condrossarcoma é um dos tumores primários malignos mais frequentes. As localizações das raízes pélvicas e da coxa exigirão amplas abordagens com a conseqüente dificuldade em cobrir os tecidos moles. A hemipelvectomia externa costuma ser o procedimento de escolha para esses locais. Envolve a ressecção do membro inferior em bloco associado à hemipelve ipsilateral, resultando em um grande defeito de cobertura. Em algumas circunstâncias, a ressecção extensa de partes moles impossibilita o uso de retalhos rotacionais locais. A reconstrução com retalhos de filé oferece a esses defeitos de tecidos moles a opção de obter uma cobertura adequada. O objetivo deste trabalho é mostrar a resolução de um caso não convencional de condrossarcoma do fêmur proximal e sua reconstrução de partes moles com método nunca antes utilizado em nosso meio.

Evaluation of a novel classification system to predict local recurrence in sarcoma patients undergoing hemipelvectomy with iliosacral resection.

AIMS: Iliosacral sarcoma resections have been shown to have high rates of local recurrence (LR) and poor overall survival. There is also no universal classification for the resection of pelvic sarcomas invading the sacrum. This study proposes a novel classification system and analyzes the survival and risk of recurrence, when using this system. METHODS: This is a retrospective analysis of 151 patients (with median follow-up in survivors of 44 months (interquartile range 12 to 77)) who underwent hemipelvectomy with iliosacral resection at a single centre between 2007 and 2019. The proposed classification differentiates the extent of iliosacral resection and defines types S1 to S6 (S1 resection medial and parallel to the sacroiliac joint, S2 resection through the ipsilateral sacral lateral mass to the neuroforamina, S3 resection through the ipsilateral neuroforamina, S4 resection through ipsilateral the spinal canal, and S5 and S6 contralateral sacral resections). Descriptive statistics and the chi-squared test were used for categorical variables, and the Kaplan-Meier survival analysis were performed. RESULTS: Resections were S1 in 25/151 patients (17%), S2 in 70/151 (46%), S3 in 33/151 (22%), S4 in 77/151 (11%), S5 in 4/151 (3%), and S6 in 2/151 (1%). An internal hemipelvectomy was performed in 113/151 patients (75%), and 38/151 patients (25%) had an external hemipelvectomy. The predominant types of sarcoma were high-grade osteosarcoma in 48/151 patients (32%), chondrosarcoma in 41/151 (27%), Ewing sarcoma in 33/151 (22%), pleomorphic sarcoma in 17/151 (11%), and others in 2/151 (8%). LR was found in 24/151 patients (15%) with S3, S5, with S6 resections showing the highest rate of LR (p = 0.038). Overall, 19/151 patients (16%) had evidence of metastastic disease at the time of surgery and these patients showed poorer survival when compared to patients with no metastasis. CONCLUSION: The proposed classification can help to report and compare different surgical and reconstructive approaches in these difficult cases who are still have a considerable risk of LR. Cite this article: Bone Joint J 2022;104-B(2):290-296.

Pelvic ring reconstruction with double-barreled fibular free flap: A systematic review.

INTRODUCTION: Pelvic ring reconstruction after internal hemipelvectomy is an extremely challenging surgical procedure, and mandatory reconstruction is to provide a durable and pain-free functional outcome, especially for young, active patients. One of the most widely employed techniques is reconstruction with a double-barreled fibular free flap (DBF). The aim of our work was an in-depth analysis of the outcome of pelvic ring reconstruction performed using the above-mentioned method, in particular looking for a correlation between the fixation technique and either ambulation status or complications. MATERIALS AND METHODS: A systematic review was performed in November 2020 using PubMed and MedLine Ovid databases according to the PRISMA guidelines and the results were statistically analyzed. RESULTS: Studies were published between 1994 and 2015. A DBF was used in each case, with a total of 30 patients. Reconstruction was performed with screws in 13 cases, Cotrel-Dubousset rod fixation in 6, screws and plate in 5, screws with external fixation in 4, and ISOLA in 2. Follow-up time ranged from 3 to 131 months. Functional outcome was excellent in 4 patients and good in 26 patients. Statistical analysis showed no statistical evidence of existing correlation between fixation technique and complications (p = .873), while statistical correlation between age and fixation technique was found (p < .001). CONCLUSION: Reconstruction of pelvic ring with DBF provides an overall good functional outcome. Our data indicate that there is no statistical evidence of existing correlation between the fixation technique and either complications or ambulation status.

Type lll internal hemipelvectomy for primary bone tumours with and without allograft reconstruction : a comparison of outcomes.

AIM: There is insufficient evidence to support bony reconstruction of the pubis after a type III internal hemipelvectomy (resection of all or part of the pubis). In this study, we compared surgical complications, postoperative pain, and functional outcome in a series of patients who had undergone a type III internal hemipelvectomy with or without bony reconstruction. METHODS: In a retrospective cohort study, 32 patients who had undergone a type III hemipelvectomy with or without allograft reconstruction (n = 15 and n = 17, respectively) were reviewed. The mean follow-up was 6.7 years (SD 3.8) for patients in the reconstruction group and 6.1 years (SD 4.0) for patients in the non-reconstruction group. Functional outcome was evaluated using the Musculoskeletal Tumor Society (MSTS) scoring system and the level of postoperative pain with a visual analogue scale (VAS). RESULTS: The mean MSTS score of the patients was significantly better in patients after reconstruction (26 (SD 1.7) vs 22.7 (SD 2.0); p < 0.001). The mean visual analogue scale score for pain was significantly less in the reconstruction group (2.1 (SD 2) vs 4.2 (SD 2.2); p = 0.016). One infection occurred in each group. Bladder herniation occurred in three patients (17.6%) in the non-reconstruction group but none in the reconstruction group. Five patients (29.4%) in the non-reconstruction group and one (7%) in the reconstruction group had a limp. Graft displacement occurred in two patients in the reconstruction group. CONCLUSION: We recommend reconstruction of the bony defect after a type III hemipelvectomy: it gives a better functional result, less postoperative pain, and fewer late surgical complications. Cite this article: Bone Joint J 2021;103-B(6):1155-1159.

Soft tissue reconstruction after pelvic amputation: The efficacy and reliability of free fillet flap reconstruction.

BACKGROUND: The majority of hindquarter amputation defects can be reconstructed with local anterior or posterior thigh flaps. Less than 5% of soft tissue defects require free flap reconstruction after tumour resection. Lower extremity fillet flap is described for reconstructing such defects, but the majority of publications are case reports or short single institutional series. There is a lack of data regarding the oncological outcomes of this highly selected patient group. METHODS: Three tertiary sarcoma units treated twelve patients with hindquarter amputation or hip disarticulation for oncological indications with a free flap reconstruction of the soft tissue defect. RESULTS: The median age of patients was 60 (range 12-76) years. Bone resection was carried out through the SI-joint in six patients and through the sacrum in five patients, with one patient undergoing hip disarticulation. Nine patients had R0 resection margin and three had R1 resection. The median surgical time and flap ischaemia time was 420 (249-650) and 89 (64-210) min, respectively. Median hospital and ICU stay was 18 (10-42) and 3 (1-8) days, respectively. Median blood loss was 2400 (950-10000) ml. There were three returns to theatre due to vascular compromise, with one total flap loss due to arterial thrombosis. Overall survival was 58% (95%CI 28-91%) both at 1-year and at 3-years. DISCUSSION: Carefully selected patients requiring hindquarter amputation with extensive soft tissue defect necessitating free flap reconstruction can be reconstructed with a lower extremity free fillet flap with low rate of local wound complications. Survival of these patients is similar to that in patients requiring less extensive resection.

Pelvic Ewing sarcoma: a retrospective outcome analysis of 104 patients who underwent pelvic tumor resection at a single supra-regional center.

BACKGROUND: Local treatment in pelvic Ewing sarcoma (ES) consists of operation, radiation therapy, or a combination of both. Reported outcomes vary depending on the treatment modality performed. It is the objective of this study to analyze surgical outcome and complications as well as oncological outcome and complications of chemo- and radiation therapy in this patient cohort and evaluate prognostic factors. METHODS: Retrospective review of 104 patients who underwent tumor resection for pelvic ES from 1988 to 2014. RESULTS: All patients underwent pelvic resection and radiation therapy was administered in 77.9%. Margins were clear in 94.2%. The response to chemotherapy was good in 78.8%. Local recurrence occurred in 7.7%. The presence of distant metastases at the time of operation was the most important negative predictor for overall survival (p = 0.003). The cumulative 5- and 10-year survival rates were 82.7% and 80.1% for non-metastasized and 61.4% and 41.6% for metastasized pelvic ES at operation. In the presence of a single-distant metastatic site at operation compared to multiple metastatic sites, the cumulative survival rates were 64.3% versus 50% at five and 50.7% versus 16.7% at 10 years. CONCLUSIONS: A combined treatment approach of tumor resection and radiation therapy leads to a local control and overall survival rates comparable with those of extremity locations in this study's patient cohort with localized pelvic ES. Therefore, surgical tumor resection (combined with (neo-)adjuvant radiation therapy) in non-metastatic pelvic ES seems feasible. In metastatic patients, however, the significance of tumor resection as a part of local treatment remains less certain and improved outcomes of combined local treatment approaches need to be weighed against these patients' prognosis and quality of life.

Targeted muscle reinnervation following external hemipelvectomy or hip disarticulation: An anatomic description of technique and clinical case correlates.

BACKGROUND: Targeted muscle reinnervation (TMR) has been shown to decrease or prevent neuropathic pain, including phantom and residual limb pain, after extremity amputation. Currently, a paucity of data and lack of anatomical description exists regarding TMR in the setting of hemipelvectomy and/or hip disarticulations. We elaborate on the technique of TMR, illustrated through cadaveric and clinical correlates. METHODS: Cadaveric dissections of multiple transpelvic exposures were performed. The major mixed motor and sensory nerve branches were identified, dissected, and tagged. Amputated peripheral nerves were transferred to identified, labeled target motor nerves via direct end-to-end nerve coaptations per traditional TMR technique. A retrospective review was completed by our multi-institutional teams to include examples of clinical correlates for TMR performed in the setting of hemipelvectomies and hip disarticulations. RESULTS: A total of 12 TMR hemipelvectomy/hip disarticulation cases were performed over a 2 to 3-year period (2018-2020). Of these 12 cases, 9 were oncologic in nature, 2 were secondary to traumatic injury, and 1 was a failed limb salvage in the setting of chronic refractory osteomyelitis of the femoral shaft. CONCLUSIONS: This manuscript outlines the technical considerations for TMR in the setting of hemipelvectomy and hip disarticulation with supporting clinical case correlates.

Pelvic ring reconstruction with segmental spinal instrumentation after complete type I pelvic resection.

BACKGROUND AND OBJECTIVES: Internal hemipelvectomy is a complex procedure used to treat malignancy that involves the pelvis. Reconstruction of the pelvis after type I or type I/IV resection remains controversial due to high complication rates and debatable functional benefit. Modern reconstruction options may provide a rapid, intuitive, and reliable way to reconstitute the pelvic ring. METHODS: This is a retrospective case series of four patients who underwent a novel reconstruction method involving computer navigation and segmental spinal instrumentation applied to the pelvis after type I or type I/IV pelvic resection for malignancy between 2015 and 2020. RESULTS: Time to ambulation postoperatively ranged from 1 to 7 days, and median length of hospital stay was 8.5 (7.5, 10.5) days. Complications included wound necrosis in two patients that did not require reoperation and wound infection in one patient that required irrigation and debridement. There was no radiographic evidence of hardware loosening or failure on follow-up. Three patients remain alive and two remain disease-free. At most recent follow-up, all patients were able to ambulate and perform activities of daily living. CONCLUSIONS: The technique for pelvic reconstruction described allows for rapid fixation intraoperatively with few complications and satisfactory functional results in this limited series.

Restoration of Spinopelvic Continuity with the Free Fibula Flap after Limb-Sparing Oncologic Resection Is Associated with a High Union Rate and Superior Functional Outcomes.

BACKGROUND: Type 1 internal hemipelvectomies and total sacrectomies cause significant biomechanical instability, demanding pelvic ring reconstruction for ambulation and torso support. Previously described methods include autografts, allografts, and implants, commonly with poor long-term outcomes. The authors hypothesized that the free fibula flap for spinopelvic reconstruction is safe and effective, and associated with a high bony union rate and superior functional outcomes. METHODS: The authors performed a retrospective review of all patients who underwent free fibula flap surgery after internal hemipelvectomy or total sacrectomy at M. D. Anderson Cancer Center from 2003 to 2018. The primary outcome was radiographic evidence of bony union. Secondary outcomes included surgical-site occurrence and lower extremity function. Univariate and multivariate logistic regression analyses were performed. RESULTS: Forty-seven patients were included (internal hemipelvectomy, n = 38; total sacrectomy, n = 9). The mean follow-up was 3.3 years and the most common abnormality was chondrosarcoma (30.4 percent). The nonunion rate was 9.7 percent and the surgical-site occurrence rate was 34 percent; there were no flap losses. Greater age was significantly associated with nonunion (OR, 1.1; 95 percent CI, 1 to 1.2; p = 0.003), whereas obesity was the only independent predictor of surgical-site occurrence (OR, 9.2; 95 percent CI, 1.2 to 71.3; p = 0.03). Functional metrics approached those of adult norms by 3 years postoperatively. Compared to internal hemipelvectomy patients, patients undergoing total sacrectomy had more comorbidities, a higher complication rate, and a worse functional outcome. CONCLUSION: The free fibula flap for spinopelvic reconstruction is safe and effective, and is associated with a high bony union rate and superior functional outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Internal Hemipelvectomy and Reconstruction Assisted by 3D Printing Technology Using Premade Intraoperative Cutting and Placement Guides in a Patient With Pelvic Sarcoma: A Case Report.

CASE: We describe the case of a 75-year-old patient diagnosed with high-grade epithelioid hemangioendothelioma in the left hemipelvis. She underwent an internal hemipelvectomy, followed by reconstruction with a tumor prosthesis with iliac anchorage using 3D-printed cutting and placement guides. Eighteen months postoperatively, she is pain-free and walks without appliances. CONCLUSIONS: Using 3D-printed guides could be an appropriate alternative for patients with aggressive bone tumors in the pelvic area that require hemipelvectomy and reconstruction using a prosthesis with iliac anchorage. 3D-printed cutting guides allow precise resection with appropriate margins, could reduce the risk of injuring critical structures, and facilitate proper prosthetic component positioning.

Unusual localization and aggressive progression of large infantile fibrosarcoma.

Infantile fibrosarcoma is a very rare soft tissue tumor in infants and children most commonly located in extremities. It constitutes less then 1 percent of all childhood cancers. Prognosis and clinical course of it is relatively good compared to adult forms. Local recurrence is common but metastasis is infrequent. In this case report we present infantile fibrosarcoma with relapse and lung metastasis despite neoadjuvant chemotherapy, pelvic reconstruction surgery with wide surgical excision and adjuvant chemotherapy protocol. The patient was a 2-year-old girl at the time of diagnosis, and there was a huge mass in pelvic region. After neoadjuvant chemotherapy, type 1 pelvic resection and pelvic reconstruction with bone cement performed. The patient presented with relapse and lung metastasis 6 months after the surgery. This is the first report of pelvic infantile fibrosarcoma with pelvic resection surgery. This case suggests that these tumors may exhibit unpredictable clinical behavior.

Free fillet lower leg flap for coverage after hemipelvectomy or hip disarticulation.

INTRODUCTION: Tumor resection is the gold standard treatment for soft tissue and bone sarcomas. In the pelvis, this may require a hemipelvectomy that can compromise primary skin closure. Flaps are essential in this context; however the vascularization of potential pedicled flaps may have been removed during tumor excision. Using healthy tissue from the amputated limb as a free flap is an excellent coverage option. HYPOTHESIS: The free fillet flap from an amputated lower limb is a simple and reliable coverage technique after hemipelvectomy or hip disarticulation. MATERIAL AND METHODS: Seven patients were operated on at three specialty centers: six transpelvic amputations (external hemipelvectomy) and one hip disarticulation. In three cases, the flap consisted of the superficial posterior compartment of the calf area and in the three other cases, the lower leg compartments with the fibula and its intact periosteum. Complications were documented. RESULTS: Clear resection margins were achieved in all patients. The mean follow-up at the final visit was 13 months (range, 6.5 to 21 months). Six patients had complications but only one resulted in loss of the flap. Four patients were able to be fitted with a hip prosthesis. DISCUSSION: The free fillet flap from an amputated lower limb is a reliable coverage technique (86%) after hemipelvectomy or hip disarticulation. In the 16 cases previously reported in the literature, there were no wound-healing failures. Local flaps are often too fragile with insufficient muscular padding. This free flap is the preferred first-line technique as it spares other potential free flaps in case of failure without increasing the morbidity of a procedure that is already extensive. This coverage technique should be one the options considered after external hemipelvectomy. LEVEL OF EVIDENCE: IV, retrospective study.

Posterior "Open Book" approach for type 1 internal hemipelvectomy.

INTRODUCTION: Internal limb-sparing hemipelvectomy is currently the preferred surgical option for resection of pelvic tumours. Obtaining an acceptable functional outcome through the standard ilioinguinal or iliofemoral incisions, only compounds the already challenging dissection, resection and reconstruction of these extensive en-bloc extirpative oncologic operations. SURGICAL TECHNIQUE: We describe a novel surgical approach to the lateral pelvis that minimises injury to the gluteal muscles, spares the gluteal vessels and provides a broad yet shallow operative field conducive to microsurgery with sizeable vasculature in close proximity to facilitate any microsurgical reconstruction. Access to the ilium and sacrum for Enneking Type 1 and Type 4 resections respectively is obtained by reflecting a skin and soft tissue flap anteriorly while the gluteal muscles are reflected posteriorly and inferiorly. This technique minimises the amount of tissue reflected in any particular direction, therefore, providing a broad and shallow operative field which benefits the orthopaedic oncologic surgeon and the plastic reconstructive surgeon. CONCLUSION: The "posterior open-book" approach offers a promising alternative to the standard ilioinguinal or iliofemoral incisions for internal limb-sparing Type 1 hemipelvectomies while also optimising the exposure for subsequent reconstructive procedures.