The use of extracorporeally irradiated autografts in pelvic reconstruction following tumour resection

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.

Biomechanical and clinical outcomes of 3D-printed versus modular hemipelvic prostheses for limb-salvage reconstruction following periacetabular tumor resection: a mid-term retrospective cohort study

BACKGROUND

Debates persist over optimal pelvic girdle reconstruction after acetabular tumor resection, with surgeons grappling between modular and 3D-printed hemipelvic endoprostheses. We hypothesize superior outcomes with 3D-printed versions, yet scarce comparative research exists. This study fills the gap, examining biomechanics and clinical results retrospectively.

METHODS

From February 2017 to June 2021, we retrospectively assessed 32 patients undergoing en bloc resection for malignant periacetabular tumors at a single institution.

PRIMARY OUTCOME

limb function.

SECONDARY OUTCOMES

implant precision, hip joint rotation center restoration, prosthesis-bone osteointegration, and complications. Biomechanical characteristics were evaluated through finite element analysis on pelvic defect models.

RESULTS

In the 3D-printed group, stress distribution mirrored a normal pelvis, contrasting the modular group with elevated overall stress, unstable transitions, and higher stress peaks. The 3D-printed group exhibited superior functional scores (MSTS: 24.3 ± 1.8 vs. 21.8 ± 2.0, p < 0.05; HHS: 79.8 ± 5.2 vs. 75.3 ± 3.5, p < 0.05). Prosthetic-bone interface osteointegration, measured by T-SMART, favored 3D-printed prostheses, but surgery time (426.2 ± 67.0 vs. 301.7 ± 48.6 min, p < 0.05) and blood loss (2121.1 ± 686.8 vs. 1600.0 ± 505.0 ml, p < 0.05) were higher.

CONCLUSIONS

The 3D-printed hemipelvic endoprosthesis offers precise pelvic ring defect matching, superior stress transmission, and function compared to modular endoprostheses. However, complexity, fabrication expertise, and challenging surgical implantation result in prolonged operation times and increased blood loss. A nuanced consideration of functional outcomes, complexity, and patient conditions is crucial for informed treatment decisions.

LEVEL OF EVIDENCE

Level III, therapeutic study (Retrospective comparative study).

Clinical exploration of the international society of limb salvage classification of endoprosthetic failure using Henderson in the application of 3D-printed pelvic tumor prostheses

Background

The use of 3D-printed pelvic prosthesis for postoperative reconstruction after pelvic tumor resection has become one of the primary reconstruction methods the incidence of complications related to postoperative prosthesis reconstruction is high. Drawing on the failure of the type of bone tumor reconstruction in Henderson,the occurrence of postoperative complications was explored to take advantage of the design improvement of the 3D-printed prosthesis of subsequent pelvic tumors.

Methods

The data for patients who underwent 3D-printed pelvic tumor prostheses in the Department of Bone and Soft Tissue Surgery at the Affiliated Cancer Hospital of Guangxi Medical University from January 2019 to October 2022 were collected and analyzed.

Results

The median follow-up time for all patients was 15.99 months (1.33-31.16 months). At the most recent follow-up,all patients were alive,with an average Musculoskeletal Tumor Society (MSTS) score of 21.46 (17 to 26 points). Local recurrence occurred in two cases (15.3%), metastasis in four cases (30.7%), and complications in 10 cases (76.9%). Early complications after surgery were primarily local wound fissure, deep tissue infection, and postoperative neuralgia. Later complications included loose dissolution of internal fixation, postoperative prosthetic dislocation, and postoperative gluteal middle muscle gait.

Conclusion

3D printing personalized design pelvic tumor prosthesis is an effective way to reconstruct, and designing pelvic 3D printed tumor prosthesis with the help of Henderson's bone tumor reconstruction failure concept may help bone tumor surgeons develop better pelvic tumor prosthesis.

Design of 3D-printed prostheses for reconstruction of periacetabular bone tumors using topology optimization

Background: Prostheses for the reconstruction of periacetabular bone tumors are prone to instigate stress shielding. The purpose of this study is to design 3D-printed prostheses with topology optimization (TO) for the reconstruction of periacetabular bone tumors and to add porous structures to reduce stress shielding and facilitate integration between prostheses and host bone. Methods: Utilizing patient CT data, we constructed a finite element analysis (FEA) model. Subsequent phases encompassed carrying out TO on the designated area, utilizing the solid isotropic material penalization model (SIMP), and this optimized removal area was replaced with a porous structure. Further analyses included preoperative FEA simulations to comparatively evaluate parameters, including maximum stress, stress distribution, strain energy density (SED), and the relative micromotion of prostheses before and after TO. Furthermore, FEA based on patients' postoperative CT data was conducted again to assess the potential risk of stress shielding subsequent to implantation. Ultimately, preliminary follow-up findings from two patients were documented. Results: In both prostheses, the SED before and after TO increased by 143.61% (from 0.10322 to 0.25145 mJ/mm3) and 35.050% (from 0.30964 to 0.41817 mJ/mm3) respectively, showing significant differences (p < 0.001). The peak stress in the Type II prosthesis decreased by 10.494% (from 77.227 to 69.123 MPa), while there was no significant change in peak stress for the Type I prosthesis. There were no significant changes in stress distribution or the proportion of regions with micromotion less than 28 μm before and after TO for either prosthesis. Postoperative FEA verified results showed that the stress in the pelvis and prostheses remained at relatively low levels. The results of follow-up showed that the patients had successful osseointegration and their MSTS scores at the 12th month after surgery were both 100%. Conclusion: These two types of 3D-printed porous prostheses using TO for periacetabular bone tumor reconstruction offer advantages over traditional prostheses by reducing stress shielding and promoting osseointegration, while maintaining the original stiffness of the prosthesis. Furthermore, in vivo experiments show that these prostheses meet the requirements for daily activities of patients. This study provides a valuable reference for the design of future periacetabular bone tumor reconstruction prostheses.

Pelvic-girdle reconstruction with three-dimensional-printed endoprostheses after limb-salvage surgery for pelvic sarcomas: current landscape

Resection of pelvic bone tumors and the subsequent reconstruction of the pelvic girdle pose challenges due to complex anatomy, load-bearing demands, and significant defects. 3D-printed implants have revolutionized pelvic girdle reconstruction by offering customized solutions, porous surface structures for precise resection with custom guides, and improved integration. Many tertiary medical centers have adopted 3Dprinted hemipelvic endoprostheses, leading to enhanced outcomes. However, most studies are limited to single centers, with a small number of cases and short follow-up periods. Additionally, the design of these implants often relies heavily on individual experience, resulting in a lack of uniformity and significant variation. To provide a comprehensive assessment of this technology, we conducted an analysis of existing literature, encompassing tumor resection classification, various types of prosthesis design, reconstruction concepts, and post-reconstruction functional outcomes.

Custom designed and 3D-printed titanium pelvic implants for acetabular reconstruction after tumour resection

BACKGROUND

Reconstructive procedure following resection of large pelvic tumours around the hip joint remains a complex challenge.

METHODS

This study presents a retrospective case series of patients presenting with benign or malignant pelvic tumour for which an internal hemipelvectomy including the hip joint and subsequent reconstruction with a custom designed 3-dimensional printed titanium pelvic implant (3DPPI) has been performed between August 2013 and January 2018.

RESULTS

15 consecutive patients with a median age of 33.9 years (IQR 26.4-72.2) and a median BMI of 20.7 kg/m2 (IQR 19.0-33.3) were reviewed after median follow-up of 33.8 months (IQR 24.0-78.1). The majority of patients presented with a malignant tumour as their principal diagnosis (n = 13, 86.7%). The median surgical time was 5.5 hours (IQR 4.5-8.5) and median peri-operative blood loss was 5000 ml (IQR 2000-10000). The median MSTS score at follow-up was 63.3% (IQR 51.7-86.7%). The median NRS in rest was 0.0 (IQR 0.0-5.0), the median NRS during activity was 2.0 (IQR 0.5-7.0) and the median HOOS-PS was 76.6% (IQR 67.9-91.0). 4 patients had implant-specific complications (n = 4, 26.6%); 1 hip dislocation (Henderson type 1a), 3 structural complications (type 3a), 1 deep infection (type 4a) and 1 local tumour recurrence (type 5b). At follow-up, 4 out of 15 implants were classified as a failure, resulting in an implant survival rate of 73.3%.

CONCLUSIONS

Acceptable peri-operative outcomes, functional results, complication rates and short-term implant survival can be achieved in a cohort of complex patients undergoing 3DPPI reconstruction after hemipelvectomy including the acetabulum.

Pelvic bone sarcomas, prognostic factors, and treatment: A narrative review of the literature

Primary sarcomas of bone are rare malignant mesenchymal tumors. The most common bone sarcomas are osteosarcoma, Ewing's sarcoma, and chondrosarcoma. The prognosis has improved over the years, but bone sarcomas are still life-threatening tumors that need a multidisciplinary approach for diagnosis and treatment. Bone sarcomas arising in the pelvis present a unique challenge to orthopedic oncologists due to the absence of natural anatomical barriers, the close proximity of vital neurovascular structures, and the high mechanical demands placed on any pelvic reconstruction following the excision of the tumor. While radiotherapy has an important role especially in Ewing's sarcoma and chemotherapy for both Ewing's sarcoma and osteosarcoma, surgery remains the main choice of treatment for all three entities. While external hemipelvectomy has remained one option, the main aim of surgery is limb salvage. After complete tumor resection, the bone defect needs to be reconstructed. Possibilities to reconstruct the defect include prosthetic or biological reconstruction. The method of reconstruction is dependent on the location of tumor and the surgery required for its removal. The aim of this article is to give an insight into pelvic bone sarcomas, their oncological and surgical outcomes, and the options for treatment based on the authors' experiences.

What are the 2-year survivorship outcomes of custom hemipelvis reconstruction after hemipelvectomy and revision arthroplasty? The evolution of a custom ilium "monoflange"

BACKGROUND

Innovations in machined and three-dimensionally (3D) printed implant technology have allowed for customized complex pelvic reconstructions. We sought to determine the survivorship of custom hemipelvis reconstruction using ilium-only fixation at a minimum 2-year follow-up, their modes of failure, and the postoperative complications resulting from the procedure.

METHODS

A retrospective review identified 12 consecutive patients treated with custom hemipelvis reconstruction. Indications for surgery were bone tumor requiring internal hemipelvectomy (four patients) or multiply revised, failed hip arthroplasty with massive bone loss (eight patients). All patients had a minimum of 2-year follow-up with a mean of 60.5 months. Kaplan-Meier survivorship analysis was determined for all patients. Postoperative complications and reoperations were categorized for all patients.

RESULTS

At a mean of 60.5 months, 11 of 12 patients had retained their custom implant (92% survivorship). One implant was removed as a result of an acute periprosthetic joint infection (PJI). There were no cases of aseptic loosening. Seven of 12 patients required reoperation (three PJI; two dislocations; two superficial wound complications), with five patients going on to reoperation-free survival.

CONCLUSIONS

Custom hemipelvis reconstruction utilizing an ilium monoflange provides durable short-term fixation at a minimum 2-year follow-up. Reoperation for infection and dislocation is common.

Reconstruction of Type I-II Internal Hemipelvectomy in a Patient With Pelvic Myxoid Chondrosarcoma: A Case Report

Pelvic chondrosarcomas are a major clinical challenge since the only therapeutic approach available is surgical resection. Reconstruction after partial resection of the pelvis including the acetabulum or the hip joint is a laborious and rigorous surgical procedure. Numerous complications are associated with different reparative methods. Moreover, due to the anatomical complexities of the area, adequate surgical margins are difficult to achieve in many cases, which are closely related to the advent of local recurrence of the tumor. Several techniques for hip function restoration and skeletal reconstruction have been reported. The purpose of this report is to describe a novel pelvic reconstruction technique for PI-II resection that required a custom-designed implant. We present the case of a 61-year-old female patient with chronic pain in the gluteal region. The pelvis’s magnetic resonance imaging (MRI) showed an osteolytic tumor in the right iliac wing that compromises the acetabular roof. The diagnosis was a grade 2 central chondrosarcoma. Surgery included the reconstruction of the acetabulum by inserting two Schanz pins coated with hydroxyapatite, one in the iliopubic corridor and the other in the ischium. A supporting “pyramid” was built, unitizing both Schanz with cement, onto which an acetabular cage was inserted. The procedure was completed with a conventional total hip prosthesis. The patient presented an acute prosthesis infection, which positively responded to prompt surgical lavage and antibiotic treatment. After 10 months of follow-up, the patient remains free of infection, with weight-bearing as tolerated, without pain, and with excellent hip motion. No tumor recurrence has occurred. Medialization of the construct has occurred as expected, with no evidence of implant loosening. The technique used in this patient is novel, could be considered cost-effective, and has allowed the reconstruction of a functional hip. For resections of the acetabular area and preservation of the ischium and pelvic zones, this technique may be an acceptable option.

Late Distal Ureteral Stricture in Internal Hemipelvectomy Without Bone Reconstruction: A Case Report

We report the case of a patient with Ewing sarcoma involving the right pelvis in a 14-year-old girl who had multicycles of neo-adjuvant chemotherapy and preoperative radiation therapy. She underwent an internal hemipelvectomy type I resection, according to Enneking and Dunham’s classification without bony reconstruction. There was no intra- and perioperative complication. The patient has good function and needs no gait aids. She can walk with equinus foot compensated for leg shortening 5 centimeters and without a shoe-lift. There is no sign of disease relapse. However, she developed late ureteral stricture at 8-year postoperatively and was successfully treated with a ureteral stent.

A novel limb-salvage reconstruction strategy with a custom hemipelvic endoprosthesis and preserved femoral head following the resection of periacetabular tumors: A preliminary study

The treatment of periacetabular malignancy frequently challenges surgeons. To simplify the surgical procedure, we performed a novel reconstruction strategy preserving the femoral head for patients with periacetabular malignancies. We retrospectively reviewed 14 patients who underwent total en bloc resection of a periacetabular tumor and reconstruction of the hip joint with an individualized hemipelvic endoprosthesis and remaining femoral head from July 2015 to January 2019 at our center. Regions of pelvic resection: region II-4 (28.6%), region I + II-5 (35.7%), region II + III-2 (14.3%) and region I + II + III-3 (21.4%). The oncological outcomes were that 13 patients survived without disease and one patient survived with lung metastasis. None of the patients experienced local recurrence (range: 20-62 months; mean: 32 months). The incidence of postoperative complications was 35.7%, including delayed wound healing and deep venous thrombosis. No prosthesis-related complications occurred until the last follow-up in this study (range: 20-62 months; mean: 32 months). The mean Musculoskeletal Tumor Society functional outcome score was 23.2. The mean Toronto Extremity Salvage Score of the patients was 75.7 points, with a mean limb discrepancy of 1.51 cm (range: 0.5-3.2 cm). Reconstruction with preservation of the femoral head showed acceptable early functional and oncological outcomes, and it had an acceptable complication rate.

Surgical Treatment of Bone Sarcoma

Bone sarcomas are rare primary malignant mesenchymal bone tumors. The three main entities are osteosarcoma, chondrosarcoma, and Ewing sarcoma. While prognosis has improved for affected patients over the past decades, bone sarcomas are still critical conditions that require an interdisciplinary diagnostic and therapeutic approach. While radiotherapy plays a role especially in Ewing sarcoma and chemotherapy in Ewing sarcoma and osteosarcoma, surgery remains the main pillar of treatment in all three entities. After complete tumor resection, the created bone defects need to be reconstructed. Possible strategies are implantation of allografts or autografts including vascularized bone grafts (e.g., of the fibula). Around the knee joint, rotationplasty can be performed or, as an alternative, the implantation of (expandable) megaprostheses can be performed. Challenges still associated with the implantation of foreign materials are aseptic loosening and infection. Future improvements may come with advances in 3D printing of individualized resection blades/implants, thus also securing safe tumor resection margins while at the same time shortening the required surgical time. Faster osseointegration and lower infection rates may possibly be achieved through more elaborate implant surface structures.

Extra-articular resection of the hip joint for pelvic sarcomas: Are there any oncological and functional risks compared with intra-articular resection?

BACKGROUND

While extra-articular resection (EAR) of the knee and shoulder joint is associated with poorer clinical outcomes, the oncological and functional risks of EAR of the hip joint are unknown. We aimed to compare these risks between EAR of the hip joint and intra-articular resection (IAR).

METHODS

We conducted a comparative study of 75 patients who underwent en-bloc tumour resection and limb-salvage reconstruction for bone sarcomas of the peri-acetabulum between 1996 and 2016. We divided patients into two groups for analyses; EAR (n = 21) and IAR (n = 54).

RESULTS

There was no statistical difference in oncological outcomes; the 5-year cumulative incidence of disease-specific death was 34% and 35% in the EAR and IAR groups, respectively (p = 0.943), and the 5-year cumulative incidence of LR was 26% and 34%, respectively (p = 0.482). The most common complications were dislocation (28%) and deep infection (28%); there was equally no difference between the groups. The mean Musculoskeletal Tumour Society score was 66% and 65% in the EAR and IAR groups, respectively (p = 0.795), and were significantly lower in patients with deep infection (52% vs. 69%; p = 0.013). In a sub-analysis on the outcomes in patients who underwent PI-uninvolved PII-resection for chondrosarcoma, no major differences in oncologic and functional outcomes were confirmed.

CONCLUSION

Patients undergoing EAR and limb-salvage reconstructions of the hip joint have undistinguishable oncological, clinical and functional outcomes compared to those undergoing IAR and reconstructions. If preoperative imaging suggests articular tumour involvement, there appears to be no detrimental effect of undertaking EAR to optimise local control.

Periacetabular reconstruction following limb-salvage surgery for pelvic sarcomas

Limb-salvage surgery for pelvic sarcomas remains one of the most challenging surgical procedures for musculoskeletal oncologists. In the past several decades, various surgical techniques have been developed for periacetabular reconstruction following pelvic tumor resection. These methods include endoprosthetic reconstruction, allograft or autograft reconstruction, arthrodesis, and hip transposition. Each of these procedures has its own advantages and disadvantages, and there is no consensus or gold standard for periacetabular reconstruction. Consequently, this review provides an overview of the clinical outcomes for each of these reconstructive options following pelvic tumor resections. Overall, high complication rates are associated with the use of massive implants/grafts, and deep infection is generally the most common cause of reconstruction failure. Functional outcomes decline with the occurrence of severe complications. Further efforts to avoid complications using innovative techniques, such as antibiotic-laden devices, computer navigation, custom cutting jigs, and reduced use of implants/grafts, are crucial to improve outcomes, especially in patients at a high risk of complications.

Unravelling the heterogeneity of soft tissue and bone sarcoma patients' health-related quality of life: a systematic literature review with focus on tumour location

Patients with sarcoma experience many physical and psychological symptoms, adversely affecting their health-related quality of life (HRQoL). HRQoL assessment is challenging due to the diversity of the disease. This review aims to unravel the heterogeneity of HRQoL of patients with sarcoma with regard to tumour location and to summarise the used measures in research. English-language literature from four databases published between January 2000 and April 2019 was reviewed. Studies that described adult sarcoma HRQoL outcomes were included and classified according to primary sarcoma location. Eighty-seven articles met the inclusion criteria covering sarcoma of the extremities (n=35), pelvis and axial skeleton (n=9), pelvis and extremities (n=5), head and neck (n=4), retroperitoneum (n=2) and multiple sarcoma locations (n=33), respectively. Urogenital and thoracic sarcoma were lacking. Fifty-four different questionnaires were used, most often cancer-generic or generic HRQoL questionnaires. Patients with sarcoma reported lower HRQoL than the general population. Distinctive patterns of HRQoL outcomes according to tumour location regarding symptoms, physical functioning, disability and psychosocial well-being were identified. In metastatic sarcoma, mostly constitutional symptoms were present. To comprehensively assess HRQoL, a sarcoma-specific measurement strategy should be developed and used covering the heterogeneity of sarcoma including location-specific issues to improve personalised HRQoL assessment in future research and clinical practice.

3D-Printed Titanium Custom-Made Prostheses in Reconstruction after Pelvic Tumor Resection: Indications and Results in a Series of 14 Patients at 42 Months of Average Follow-Up

Wide resection is currently considered the mainstay treatment for primary bone tumors. When the tumor is located in anatomically complex segments, 3D-Printed Titanium Custom-Made Prostheses (3DPTCMP) are possible reconstructive solutions. The aim of the present paper is to analyze indications, results and complications of a series of 14 patients who underwent pelvis reconstruction with 3DPTCMP after tumor removal from January 2015 to December 2019. Chondrosarcoma was the main histology; indications were tumors located in the acetabular area without enough residual bone to support a cup with an iliac stem, and tumors located near the sacrum-iliac joint. The margins were wide in 12 cases, and marginal and intralesional in one case each. In three cases, resection also included the sacrum-iliac joint, so a spine stabilization was performed and linked to the pelvic prosthesis; The average MSTS score was 46.3%; the 5-year local recurrence-free survival was 85.7%. Wound dehiscences were the main complication, resolved with multiple debridements; nevertheless, prosthesis removal was necessary in one case. Currently, the 3DPTCMP is an effective resource for reconstruction after resection of tumors located in the pelvis. Further studies are necessary to value long-term results; more strategies are necessary to try to reduce the infection rate and improve osteointegration.

Comparison of recycled autograft versus allograft in osteosarcoma with pathological fracture

PURPOSE

The recycled autograft in biological reconstruction for osteosarcoma has satisfactory outcome. There are few studies about its efficacy in pathological fracture. The aim of the study is to compare the clinical results of recycled autograft to those of allograft in patients with high-grade osteosarcoma with pathological fracture.

PATIENTS AND METHODS

Between October 2010 and March 2018, 30 patients with osteosarcoma combining pathological fracture underwent biological reconstruction. Eleven patients received recycled autograft via extracorporeal irradiation or freezing nitrogen and nineteen patients restored bone defect via allograft to accomplish biological reconstruction.

RESULTS

The mean follow-up was 58.1 months (range 12-120). The mean time to graft-host union of limbs reconstructed using recycled autografts and allografts was 17.45 ± 13.54 and 12.63 ± 12.62 months, respectively, with no significant difference observed between groups (p = 0.176). The five year probability of graft failure therefore did not significantly differ between groups (p = 0.245). The patient five year survival rate was similar (p = 0.229). Post-operative complication rates were similar for the recycled autograft group (54.5%) and the allograft group (57.9%).

CONCLUSION

The recycled autograft showed comparable clinical results, graft-host union time, complication rate, and graft survival to allograft in biological reconstruction for osteosarcoma with pathological fracture.

Osteosarcoma Mimicking Tenosynovial Giant Cell Tumor of the Hip in a Pediatric Patient: A Case Report

CASE

A 17-year-old boy presented to the clinic complaining of right hip pain after soccer participation. Clinical findings and imaging studies led to the diagnoses of femoroacetabular impingement and diffuse tenosynovial giant cell tumor (TGCT). Comprehensive arthroscopic management and biopsy revealed a diagnosis of osteosarcoma. The patient subsequently underwent chemotherapy, surgical resection, and reconstruction.

CONCLUSION

Osteosarcoma of the proximal femur may mimic TGCT on imaging studies because osteosarcoma may show changes suggestive of inflammation. We recommend heightened clinical awareness and a comprehensive differential workup in the management of presumed TGCT about the hip in the pediatric patient population.

Limb-salvage reconstruction following resection of pelvic bone sarcomas involving the acetabulum

AIMS

Limb salvage for pelvic sarcomas involving the acetabulum is a major surgical challenge. There remains no consensus about what is the optimum type of reconstruction after resection of the tumour. The aim of this study was to evaluate the surgical outcomes in these patients according to the methods of periacetabular reconstruction.

METHODS

The study involved a consecutive series of 122 patients with a periacetabular bone sarcoma who underwent limb-salvage surgery involving a custom-made prosthesis in 65 (53%), an ice-cream cone prosthesis in 21 (17%), an extracorporeal irradiated autograft in 18 (15%), and nonskeletal reconstruction in 18 (15%).

RESULTS

The rates of major complications necessitating further surgery were 62%, 24%, 56%, and 17% for custom-made prostheses, ice-cream cone prostheses, irradiated autografts and nonskeletal reconstructions, respectively (p = 0.001). The ten-year cumulative incidence of failure of the reconstruction was 19%, 9%, 33%, and 0%, respectively. The major cause of failure was deep infection (11%), followed by local recurrence (6%). The mean functional Musculoskeletal Tumour Society (MSTS) scores were 59%, 74%, 64%, and 72%, respectively. The scores were significantly lower in patients with major complications than in those without complications (mean 52% (SD 20%) vs 74% (SD 19%); p < 0.001). For periacetabular resections involving the ilium, the mean score was the highest with custom-made prostheses (82% (SD 10%)) in patients without any major complication; however, nonskeletal reconstruction resulted in the highest mean scores (78% (SD 12%)) in patients who had major complications. For periacetabular resections not involving the ilium, significantly higher mean scores were obtained with ice-cream cone prostheses (79% (SD 17%); p = 0.031).

CONCLUSION

Functional outcome following periacetabular reconstruction is closely associated with the occurrence of complications requiring further surgery. For tumours treated with periacetabular and iliac resection, skeletal reconstruction may result in the best outcomes in the absence of complications, whereas nonskeletal reconstruction is a reasonable option if the risk of complications is high. For tumours requiring periacetabular resection without the ilium, reconstruction using an ice-cream cone prosthesis supported by antibiotic-laden cement is a reliable option. Cite this article: Bone Joint J 2021;103-B(4):795-803.

Pelvic Chondrosarcoma Treated by En Bloc Resection with Patient-Specific Osteotomy Guides and Reimplantation of the Extracorporeally Irradiated Bone as an Osseocartilaginous Structural Orthotopic Autograft: A Report of Two Cases with Description of the Surgical Technique

Primary tumors of the pelvis are considered difficult to treat due to the complex anatomy and the proximity of important neurovascular structures. The surgical armamentarium for the treatment of these tumors has evolved with the help of cutting-edge technology from debilitating hemipelvectomies to solutions such as precise resections guided by patient-specific instruments or computer navigation and reconstruction by modular prostheses, 3D-printed custom-made implants, or orthotopic autograft reimplantation after extracorporeal irradiation. Different combinations of these techniques have been described in the literature with various rates of success. We present two cases of pelvic chondrosarcomas successfully treated by a combination of periacetabular resection with patient-specific osteotomy guides and orthotopic reimplantation of the extracorporeally irradiated autograft resulting in retention of the native hip.

Pelvic reconstruction using an ice-cream cone prosthesis: correlation between the inserted length of the coned stem and surgical outcome

BACKGROUND

Acetabular reconstruction using an ice-cream cone prosthesis has been a reliable reconstruction option following pelvic tumour resection. However, it remains unknown which factor determines the success of this procedure. We aimed to determine risk factors for complications and functional loss in acetabular reconstruction using an ice-cream cone prosthesis.

PATIENTS AND METHODS

Fifty-four patients with malignant bone tumours who underwent acetabular reconstruction using an ice-cream cone prosthesis between 2004 and 2016 were studied. The bone-stem ratio was calculated as the ratio of the inserted length into the bone per the entire stem length.

RESULTS

A total of 26 (48%) patients had at least one complication and 11 patients (20%) required surgical interventions. The complication rates were 71% and 40% with a bone-stem ratio ≤ 50% and > 50%, respectively (p = 0.026), and the bone-stem ratio significantly stratified the risk of complications (≤ 50%: OR, 4.67 versus > 50%; p = 0.048). The mean MSTS score at the final follow-up was 60% (range 23-97%): the scores were significantly lower in patients with complications/leg-length discrepancy (52%) than in those without (79%; p = 0.002). The mean score with a bone-stem ratio ≤ 50% was significantly lower than the score with a ratio > 50%, especially in patients who underwent non-navigated reconstructions (33% versus 64%; p = 0.001).

CONCLUSION

The inserted length of the coned stem into residual bone was predictive of complications and functional outcome. Surgical indication for this procedure should be considered with the size of the remaining ilium to stabilise the prosthesis with a coned stem longer than half length.

Reconstruction after periacetabular tumor resection with Lumic® endoprosthesis: What are the midterm results?

INTRODUCTION

This study aimed to analyze the midterm outcomes of LUMiC® endoprosthetic reconstruction following periacetabular resection of primary bone sarcomas and carcinoma metastases.

PATIENTS AND METHODS

We retrospectively reviewed the charts of 21 patients (11 male [52.3%], 10 female [47.6%]; mean age 47 ± 16 years) for whom a LUMiC® endoprosthesis (Implantcast) was used to reconstruct a periacetabular defect after internal hemipelvectomy. The tumor was pathologically diagnosed as Ewing's sarcoma in six (28.5%), chondrosarcoma in 10 (47.6%), and bone metastasis from carcinoma in five (23.8%) patients.

RESULTS

The median follow-up of patients was 57.8 months (95% confidence interval: 51.9-63.7). The implant survival rate at 1, 2, and 5 years were 95.2%, 85.7%, and 80.9%, respectively. The overall complication rate was 33.3% (n = 7). Four (19%) complications resulted in reconstruction failure. Total reoperation rate was 28.5% (n = 6). The complications were soft tissue failure/dislocation in two patients, aseptic loosening in one, infection in two, and local recurrence in two. At the time of study, seven patients were alive with no evidence of disease, seven were alive with disease, and seven died of disease. The 5-year overall survival rate and local recurrence-free survival rates were 67% and 76%, respectively. The median Musculoskeletal Tumor Society score at final follow-up was 70% (range: 50%-86.6%).

CONCLUSION

We conclude that LUMiC® endoprosthesis provides good functional outcomes and a durable reconstruct. Even though this reconstruction method presents some complications, it provides a stable pelvis in the management of periacetabular malignant tumors.

What are the Complications of Three-dimensionally Printed, Custom-made, Integrative Hemipelvic Endoprostheses in Patients with Primary Malignancies Involving the Acetabulum, and What is the Function of These Patients?

BACKGROUND

Functional reconstruction after resection of pelvic malignancies involving the acetabulum remains challenging. Numerous reconstruction methods have been proposed, but they are generally associated with mechanical and nonmechanical complications. To improve the function of patients with primary malignancies of the acetabulum after internal hemipelvectomy and reduce the complication rate after this procedure, we designed a series of three-dimensionally (3D) printed, custom-made, integrative hemipelvic endoprostheses with a porous structure and wanted to present the early results of using this construct to determine whether it could be considered a reasonable reconstruction option.

QUESTIONS/PURPOSES

We performed this study to (1) evaluate, in a small group of patients, whether the new endoprosthesis restores short-term lower-limb function; (2) identify short-term complications associated with the use of this endoprosthesis; and (3) assess osseointegration between the host bone and the 3D-printed integrative hemipelvic endoprosthesis with a porous structure.

METHODS

Between October 2016 and May 2017, our center treated 26 patients with malignancies involving the acetabulum. Thirteen of these patients received hemipelvic replacement with a 3D-printed, custom-made, integrative endoprosthesis, six received hemipelvic replacement with a modular endoprosthesis, four received radiotherapy, and three received external hemipelvectomy. Resection and reconstruction with a 3D-printed, custom-made, integrative endoprosthesis were indicated if the resection margin was the same as that achieved in hemipelvectomy, if reconstruction would preserve reasonable function after resection, if the patient had a good physical status and life expectancy longer than 6 months, and if the patient was willing to accept the potential risk of a 3D-printed, custom-made, endoprosthesis. The exclusion criteria were an inability to achieve a satisfactory surgical margin with limb salvage, inability to preserve the function of the limb because of tumor involvement of the sacral nerve or sciatic nerve, and unresectable and/or widely metastatic disease on presentation. Pain and function were evaluated with the 10-cm VAS score (range 0 to 10; a lower score is desirable), the 1993 version of the Musculoskeletal Tumor Society (MSTS-93) score (range 0 to 30; a higher score is desirable), and the Harris hip score ([HHS]; range 0 to 100; a higher score is desirable) were evaluated preoperatively and at a median of 27 months after reconstruction (range 24 to 31 months). The functional scores and complications were recorded after reviewing the patients' records. Osseointegration was assessed with digital tomosynthesis by two senior surgeons. We observed the trabecular structures connected to the implant surface to assess whether there was good osseointegration.

RESULTS

The median preoperative VAS score, MSTS-93 score, and HHS were 5 (range 2 to 8), 14 (range 3 to 18), and 64 (range 20 to 76) points, respectively. At the latest follow-up interval, the median VAS score, MSTS-93 score, and HHS were 2 (range 0 to 6), 23 (range 15 to 27), and 82 (range 44 to 93) points, respectively. No deep infection, dislocation, endoprosthetic breakage, aseptic loosening, or local recurrence occurred. Two patients experienced delayed wound healing; the wounds healed after débridement. Using digital tomography, we found that all implants were well-osseointegrated at the final follow-up examination.

CONCLUSIONS

A 3D-printed, custom-made, integrative hemipelvic endoprosthesis provides acceptable early outcomes in patients undergoing pelvic reconstruction. Osseointegration is possible, and we anticipate this will lead to biologic stability with a longer follow-up interval. The custom-made integrative design ensured precise implantation. Although a few patients in this study had only a short follow-up duration, the functional results were reasonable. We have observed no major complications so far, but this was a very small series and we caution that these are large reconstructions that will certainly result in complications for some patients. Our method uses a precise preoperative simulation and endoprosthesis design to aid the surgeon in performing challenging operations. If our early results are confirmed with more patients and longer follow-up and are replicated at other centers, this may be a reconstruction option for patients with periacetabular malignancies.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Complication rate, functional outcomes, and risk factors associated with carbon ion radiotherapy for patients with unresectable pelvic bone sarcoma

BACKGROUND

To the authors' knowledge, carbon ion radiotherapy (CIRT) is one of the few curative treatments for unresectable pelvic bone sarcoma. The current study investigated the complications, functional outcomes, and risk factors of CIRT.

METHODS

Of 112 patients who were treated with CIRT for unresectable pelvic bone sarcoma, the authors enrolled 29 patients who were without local disease recurrence or distant metastasis. The mean follow-up was 93 months. Complications, functional outcomes, and quality of life scores were assessed. Risk factors were analyzed, including the dose-volume histogram of the femoral head.

RESULTS

Femoral head necrosis occurred in approximately 37% of patients, pelvic fractures were reported in 48% of patients, and neurological deficits were noted in 52% of patients. Femoral head necrosis was found to be significantly more prevalent among patients with periacetabular tumors (P = .018). The dose-volume histogram of the femoral head indicated tolerable volume percentages of the femoral head to be <33% for 40 grays (relative biological effectiveness) and 16% for 60 grays ( relative biological effectiveness). The mean Musculoskeletal Tumor Society score and Toronto Extremity Salvage Score were 53% and 64%, respectively, and the mean EuroQol 5 dimensions questionnaire index was 0.587. Patients aged >50 years and those with periacetabular tumors were found to have significantly lower Toronto Extremity Salvage Scores.

CONCLUSIONS

Femoral head necrosis, pelvic fracture, and nerve damage are common complications with the use of CIRT for pelvic bone sarcoma. To prevent femoral head necrosis, the radiation dose to the femoral head should be kept below the estimated tolerance curve presented in the current study. The functional outcome is nearly equivalent to that of surgery. CIRT may be a promising alternative to surgery for patients with unresectable pelvic bone sarcoma.

[Treatment concepts for complications after resection and defect reconstruction of pelvic tumours]

BACKGROUND

Partial pelvic resection, internal hemipelvectomy or sacrectomy as a result of bone sarcoma is still challenging. No matter what kind of reconstruction is used, there is still a much higher rate of complications in pelvic surgery compared to sarcoma surgery of the long bones.

OBJECTIVES

We describe the most common complications in pelvic sarcoma surgery and specific complications related to the reconstruction method. Handling strategies for these complications are specified.

METHODS

We performed a literature search and report our own experiences in the troubleshooting of pelvic surgery-related complications to gain an up-to-date overview of the state-of-the-art in management strategies.

RESULTS

Prospective randomized trials or meta-analyses on this topic are lacking. The literature search depicted that, besides local recurrence, deep infection after reconstruction is the most serious complication. An early revision with radical debridement has to be performed in order to save the reconstruction. In the case of a deep infection, the removal of all implants with a total loss of the reconstruction is often unavoidable. Therefore, an individualized risk-benefit analysis prior to surgery with respect to the type of reconstruction, or no reconstruction at all (hip transposition), together with the patient is advisable.

CONCLUSIONS

Complications-especially infections-after hemipelvectomy or sacrectomy are common. In the case of infection, in some cases, an early revision is the only chance to prevent a reconstruction from explantation.

Three-dimensional-printed custom-made hemipelvic endoprosthesis for primary malignancies involving acetabulum: the design solution and surgical techniques

Background

This study is to describe the detailed design and surgical techniques of three-dimensional (3D)-printed custom-made endoprosthesis for hemipelvic tumorous bone defect.

Methods

According to the pelvic tumor resection classification by Enneking and Dunham, the hemipelvis is divided into three zones including the ilium (P1), acetabulum (P2), and pubis and ischium (P3). Thirteen patients were included in this study. Of these, P1 and P2 were involved in three cases, while P1, P2, and P3 were involved in 10. Based on radiography data, 3D pelvic model was rebuilt, and virtual surgery was simulated. Different fixation methods were applied according to residual bone volume. Parameters of the first sacral (S₁) vestibule, second sacral (S₂) vestibule, the narrowest zone of superior pubic medullary cavity (NPSPMC), and the resected surface of superior pubic medullary cavity (RSSPMC) were selectively measured in various fixation methods. Model overlapping, feature simplifying, and size controlling were three basic steps during design procedure. Volume proportion of porous structure was determined according to estimated weight of resected specimen. Acetabular location, anteversion, and inclination were modulated. Screw diameter, direction, and combination were considered. The osteotomy guides and plastic models were used during surgery.

Results

Of 13 cases, after P1 resection, endoprostheses were fixed to sacra (8; 61.5%), ilia (3; 23.1%), and both (2; 15.4%). After P3 resection, endoprostheses were fixed to residual acetabulum (3; 23.1%), and residual pubis by stem (8; 61.5%) or “cap-like” structure (2; 15.4%). Mean area of the S₁ vestibule, S₂ vestibule, RSSPMC, and PSPMC were 327.9 (222.2 to 400), 131.7 (102.6 to 163.6), 200.5 (103.8 to 333.2), and 79.8 mm² (40.4 to 126.2), respectively. Porous structure with 600 μm pore size and 70% porosity accounted for 68.8% (53.0 to 86.0) of the whole endoprosthesis on average. Mean acetabular anteversion and inclination were designed as 23.2° (20 to 25) and 42.4° (40 to 45). Median numbers of screws designed in the S₁ vestibule was 5 (IQR, 4 to 6), in the S2 vestibule was 1 (IQR, 1 to 2), in the ilium was 5 (IQR, 2 to 6), and in the pubis was 1 (IQR, 1 to 1), while screws designed in the ischium was all 2. Median number of screws inserted in the S₁ vestibule was 4 (IQR, 3 to 4), in the S₂ vestibule was 1 (IQR, 1 to 1), in the ilium was 3 (IQR, 1 to 5), in the pubis was 1 (IQR, 0 to 1), and in the ischium was 1 (IQR, 1 to 1).

Conclusions

This study firstly presents detailed design and related surgical techniques of 3D-printed custom-made hemipelvic endoprosthesis reconstruction. Osseointegration is critical for long-term outcome and requires three design elements including interface connection, porous structure, and initial stability achieved by precise matching and proper fixation methods.

Surgical Outcomes After Limb-Sparing Resection and Reconstruction for Pelvic Sarcoma: A Systematic Review

BACKGROUND

Limb-sparing resection and reconstruction for pelvic sarcomas in multiple small studies have been fraught with complications, reoperations, and impaired patient function. However, the non-oncologic complication and reoperation rates and functional outcomes for patients have never been rigorously compiled, to our knowledge. A systematic review was undertaken to more accurately determine the non-oncologic complication and reoperation rates and functional outcomes for patients after pelvic sarcoma resection and reconstruction.

METHODS

The review was performed in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. PubMed and Cochrane database searches of English-only studies using the terms "pelvis AND sarcoma" and "pelvis AND sarcoma AND surgery" were performed. Study inclusion criteria were ≥10 patients enrolled, at least 12 months of follow-up, utilization of comparable functional outcome measure(s), and the majority of the resections treating primary bone sarcoma.

RESULTS

In this study, 2,350 studies were reviewed, of which 22 Level-IV studies with a total of 801 patients met inclusion criteria. Reconstructive techniques varied widely and included allografts, allograft-prosthesis composites, saddle prostheses, custom endoprostheses, and irradiated autografts. Pooled means showed a mean 5-year patient survival of 55%. The mean non-oncologic complication rate was 49%. The mean non-oncologic reoperation rate was 37%. The mean Musculoskeletal Tumor Society score was 65%.

CONCLUSIONS

The non-oncologic complication and reoperation rates for pelvic reconstructions are remarkably high and 5-year survival is poor. Functional outcomes are acceptable but may not be better than a resection of the same Enneking and Dunham type without reconstruction. Consideration should be given to forgoing pelvic reconstruction, especially in patients with poor overall prognosis. Further studies comparing non-oncologic complication rates, reoperation rates, and functional outcomes in patients with equivalent resections treated with or without reconstruction are needed to further elucidate the utility of pelvic reconstruction.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

[Hemipelvectomy for pelvic sarcomas]

BACKGROUND

Hemipelvectomy is an important technique for the treatment of pelvic sarcomas.

OBJECTIVES

Presentation of the technical overview, as well as surgical and oncological outcomes of sarcoma patients treated with pelvic tumor resections and treatment recommendations.

METHODS

Retrospective analysis of 160 patients treated by pelvic tumor resection for chondrosarcoma between 1977 and 2014.

RESULTS

Chondrosarcoma was the most common diagnosis leading to pelvic tumor resection in this collective (38%). The mean patient age at operation was 49 years. 44 patients were treated for G1, 83 patients for G2 and 33 patients for G3 or dedifferentiated chondrosarcoma. The mean tumor diameter was ≥10 cm in 76.1% of cases. Limb salvaging operations were possible in 82.5% of patients. The most common reconstruction technique was hip transposition (38.7%). Clear resection margins were achieved in 86.9% (R0). Local recurrence was observed in 22.5%. Distant pulmonal metastasis was diagnosed in 25% of patients. Grading-specific survival was 81.8% for G1, 59% for G2 and 24.2% for G3 or dedifferentiated chondrosarcoma with a mean survival of 84.4, 89 and 69.4 months respectively.

CONCLUSIONS

Pelvic tumor resection with clear margins is the most important known positive predictive local factor affecting overall outcomes, in addition to uncontrollable factors such as grading and tumor size. Defect reconstruction depends on multiple factors such as patient age and adjuvant therapy. The stage of the disease has the greatest impact on overall survival rates and should be considered when contemplating pelvic tumor resections in sarcoma patients.

Surgical treatment for pelvic Ewing sarcoma: What is a safe and functional acetabular reconstruction when combined with modern multidisciplinary treatments?

PURPOSE

The purpose of this study was to clarify which local treatment is oncologically and functionally effective in pelvic Ewing sarcoma (ES).

METHODS

A consecutive series of patients who underwent pelvic resections and acetabular reconstructions after chemotherapy between 1986 and 2016 at a supra-regional center were evaluated.

RESULTS

The cohort consisted of 35 patients. The 5-year overall survival (OS) and local recurrence-free survival (LRFS) was 61% and 72%, respectively. Preoperative radiotherapy (RT) and surgery provided an excellent/good histological response in 92% and achieved significantly better OS (5 years, 64%) and LRFS (5 years, 100%) than surgery alone or surgery with postoperative RT. The Musculoskeletal Tumor Society functional scores were significantly better in patients with hip transposition than those with structural reconstructions (74% vs 57%; P = .031) using custom-made prostheses, irradiated autografts, and ice-cream cone prostheses. These scores were significantly lower if patients had deep infection (P = .035), which was the most common complication (28%) in structural reconstructions but did not occur in hip transposition even when performed after preoperative RT.

CONCLUSION

Acetabular reconstruction with hip transposition resulted in no deep infection and superior function in patients with pelvic ES even when combined with preoperative RT, which improved tumor necrosis and rate of local control and survival.

Is an Acetabular Cage and Cement Fixation Sufficiently Durable for the Treatment of Destructive Acetabular Metastases?

BACKGROUND

Destructive bony acetabular metastases cause pain, pathological fractures, and loss of mobility. Although multiple fixation options are available, we have favored a rigid stainless steel partial pelvic cage for acetabular fixation in these patients; however, little is known about the durability of this approach. QUESTION/PURPOSES: (1) How common was loss of fixation in a small series of metastatic acetabular defects treated with an acetabular cage and cemented total hip replacement? (2) What is the implant survival free from reoperation or revision at 2 and 4 years using a competing-risks survivorship estimator in patients thus treated? (3) What complications were associated with the treatment? (4) What level of postoperative mobility was achieved?

METHODS

Between 2006 and 2017, we treated all acetabular metastases that needed surgical intervention, not amenable to conventional cemented THA alone with our single technique of acetabular partial pelvic cage and cemented total hip replacement. We treated 47 hips in 46 patients whose acetabular metastasis led to acetabular collapse or who were unresponsive to nonoperative measures of radiation therapy and analgesia. Routine followup occurred at 3 and 12 months; 17 of 46 patients (37%) died before 1 year, and all other patients were followed beyond 1 year. Only one patient who remains alive has not been seen in the past 5 years. Loss of fixation was determined by radiological or clinical signs of cage loosening. Survivorship free from reoperation or revision at 2 and 4 years was determined using competing-risks analysis. We did not assess patient-reported outcomes, but we did have data on the proportion of patients who were able to ambulate in the community and if so, what assistive devices they used, which we obtained by chart review.

RESULTS

One patient experienced cage loosening identified 8 years postoperatively as a result of local disease progression and has been managed with observation. No patients underwent revision for loss of acetabular fixation. The cumulative incidence of reoperation or revision was 8% at 2 years (95% CI, 3.6-12.6) and 16% at 4 years (95% CI, 9.2-23.2). Four patients had postoperative dislocations, of which three underwent reoperation. One patient developed a postoperative deep infection and underwent reoperation. One patient died within 30 days of surgery. Only one patient did not ambulate in the community postoperatively; 23 ambulated independently, 10 with the use of a walking stick and 12 using a walker.

CONCLUSIONS

In this small series, we found this approach sufficiently durable to continue its use for patients with acetabular metastases with collapse or those not responding to nonoperative measures. However, comparison studies are needed to determine whether it is superior or inferior to other available alternatives.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Reconstructive Challenges of Proximal Ulnar Bone Tumors: Our Experience with Biological Osteoarticular Reconstruction Using Extracorporeal Irradiation and Reimplantation

Introduction

Limb salvage surgery following proximal ulna resection poses a challenge in reconstruction of the complex elbow anatomy. Various reconstruction methods described offer inadequate restoration of function and stability. Following resection of proximal ulna tumors, we aimed to restore the joint using the resected osteochondral segment of proximal ulna treated with extracorporeal irradiation and reimplantation.

Questions/Purposes

(1) Does irradiated osteoarticular autograft reconstruction for proximal ulna allow anatomical joint restoration and what are the oncological and functional outcomes? (2) Is there evidence of graft-related complications or osteoarthritis at a minimum of 2 years follow-up with irradiated osteoarticular autografts for the proximal ulna? (3) How does our method of reconstruction fare as compared to reported reconstruction options in the literature? Materials and Methods. 3 patients with primary bone tumors involving the proximal ulna underwent limb salvage surgery with en bloc resection and reconstruction using the resected bone after treating it with extracorporeal irradiation of 50 Gy. Minimum follow-up of 2 years was considered for assessment of final outcomes. Radiographs were assessed for bony recurrence, union across osteotomy junction, and signs of joint arthritis. Functional outcome measures included range of movement, muscle power testing, and functional and disability scores.

Results

2 complete and 1 partial olecranon involving proximal ulnar resections were performed for three cases of Ewing's sarcoma in 2 males and 1 female. Follow-up ranged from 28 to 42 months, and all patients continue to remain disease free. All 3 patients have achieved full range of flexion-extension and pronosupination movement in comparison to the contralateral side. Muscle power for flexion and extension was 5/5. MSTS score: 100% (30/30); MEPS score: 100; and DASH score: zero were achieved for all patients. Union across osteotomy junctions at median follow-up of 8 months without need for intervention/bone grafting was achieved. No complications related to joint laxity/subluxation, infection, graft fracture, or implant failure was noted. None of the patients have clinical or radiological signs of joint arthritis across the irradiated articulation.

Conclusion

Biological restoration of elbow anatomy using osteoarticular irradiated graft for proximal ulna reconstruction offers great joint stability and functional outcomes. Although the potential risks of infection and graft failure need to be considered, reconstruction with the size-matched radiated autograft eliminates donor site morbidity, offers a low-cost alternative to endoprosthesis, and provides outcomes superior to any other methods of reconstruction as analyzed from the literature.

Pelvic reconstruction following resection of tumour involving the whole ilium and acetabulum

Background

Functional reconstruction following resection of pelvic tumours with the ileum and the acetabulum involvement is challenging and demanding. The aim of this study was to evaluate the results of these patients receiving pelvic reconstruction with a femoral head autograft plus a hemipelvic prosthesis.

Methods

Eighteen patients receiving pelvic reconstruction with a femoral head autograft plus a hemipelvic prosthesis following resection of pelvic tumours involving the whole ileum and the acetabulum were included in this study from April 2006 to June 2014. Oncological status, functional results, and complications of these selected patients were analysed.

Results

The follow-up was 15–125 months (median 43). The functional MSTS-93 scores of the 18 patients available for the functional analysis were 37–87% (mean 60.7%). Complications occurred in seven patients (31.8%); dislocation in two (9%); and deep infection in three patients (13.6%) and two patients healed well following thorough debridement and antibiotic treatment. Five patients had local recurrence (22.7%). Lung metastases occurred in eight patients; seven died of disease and one lived after the metastasectomy. The 5-year overall Kaplan–Meier survival and disease-free survival rates were 61.7% and 50%, respectively.

Conclusions

The procedure of femoral head autograft plus hemipelvic prosthesis was an effective method to reconstruct the defect following the whole ileum and the acetabulum resection; the functional outcomes were satisfactory, and it had an acceptable complication rate.

Combined Application of Modified Three-Dimensional Printed Anatomic Templates and Customized Cutting Blocks in Pelvic Reconstruction After Pelvic Tumor Resection

BACKGROUND

Common three-dimensional (3D)-printed anatomic templates have generally been used to reconstruct the pelvis after zone II and III borderline pelvic tumor resection. However, gradual increases in postoperative implant complications and the tumor recurrence rate have been observed. This study aimed to introduce the innovative application of a modified 3D-printed anatomic template with a customized cutting block for pelvic reconstruction and to comparatively analyze the common and modified 3D-printed anatomic templates.

METHODS

A total of 38 patients were included in this study and were allocated to 2 groups (19 patients/group). Group A received innovative therapy, and Group B received traditional therapy. All patients were questioned in detail about age, location, and duration of the mass and associated symptoms, and routine blood tests, such as serological tests, were administered.

RESULTS

We found that the modified 3D-printed anatomic template with a customized cutting block resulted in a shorter operating time, smaller bleeding loss, and simpler operation than the common 3D-printed anatomic template. Additionally, the tumor recurrence rate was lower and the accuracy of tumor resection was much greater for the modified 3D-printed anatomic template with a customized cutting block. However, compared with the traditional therapy, the innovative therapy had a significantly higher rate of implant loosening.

CONCLUSION

The innovative therapy can increase surgical safety and reduce recurrence after tumor resection relative to the traditional therapy. Additionally, the innovative therapy reconstructs the pelvis of zone III to improve the quality of patient life. However, the innovative therapy with implant loosening should be improved.

Does Extracorporeal Irradiation and Reimplantation After Acetabular Resections Result in Adequate Hip Function? A Preliminary Report

BACKGROUND

Pelvic resections are challenging, and reconstruction of the resected acetabulum to restore mobility and stability is even more difficult. Extracorporeal radiation therapy (ECRT or extracorporeal irradiation) of autograft bone and reimplantation allows for a perfect size match and has been used with some success in the extremities. Although the risk of wound complications in pelvic surgery has discouraged surgeons from using ECRT of autografts in that anatomic site, we believe it may be a reasonable option.

QUESTIONS/PURPOSES

In a small series, we asked: (1) What was the median surgical time and blood loss for these procedures, and what early complications were observed? (2) Is there evidence of osteonecrosis or cartilage loss at a minimum of 2 years after ECRT of acetabular autografts, and what functional scores were achieved? (3) What were the oncologic outcomes after ECRT?

METHODS

Between March 2007 and September 2016, one surgeon performed 12 ECRT acetabular autografts and reimplantations after resections of pelvic or acetabular tumors. Of those, 10 with minimum 2-year followup are reported on here with respect to oncologic, functional, and radiographic assessment; all 12 are reported on for purposes of surgical parameters and early complications. During that period, we generally performed this approach when we judged it possible to achieve a tumor-free margin, adequate bone stock, and sufficient remaining hip musculature to allow use of the bone as an autograft with restoration of hip mobility. We generally did not use this approach when we anticipated a difficult resection with uncertain margins or where remaining bone was judged of poor strength for use as a graft or if both iliopsoas and abductors were sacrificed. Since 2010, this series represents seven of the 21 pelvic resections with reconstruction that we performed (five patients in this series had the procedure performed before 2010). Followup was at a median of 65 months (range, 33-114 months) for nine patients whose functional outcomes were evaluated. The median patient age was 30 years (range, 10-64 years). Clinical parameters were recorded from chart review; radiographic analysis for assessment of cartilage was performed by looking for any obvious loss of joint space when compared with the opposite side. Functional scoring was done using the Musculoskeletal Tumor Society score, which was obtained from chart review. Oncologic assessment was determined for local recurrence as well as metastases.

RESULTS

Median surgical time was 8.6 hours and median blood loss was 2250 mL. There were no perioperative wound-related complications. Two patients underwent a second surgical procedure during the postoperative period, one for a femoral artery thrombus and another for a complete sciatic nerve deficit. No patients developed avascular necrosis of the femoral head. None of the patients who underwent osteoarticular grafting showed radiographic evidence of joint space narrowing. The median Musculoskeletal Tumor Society score was 28 (range, 17-30). No fractures in the radiated segment of reimplanted bone were seen in this small series.

CONCLUSIONS

Results from this small series suggest that ECRT is a potential option in selected patients who have good bone stock and adequate soft tissue coverage. Although technically challenging, ECRT is a low-cost alternative to prostheses in providing a mobile and stable hip. Although we did not observe cartilage wear on plain radiographs, followup here was short term; it may appear as we continue to follow these patients. Future studies from retrieval specimens may shed light on the actual status of cartilage on the acetabulum.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Upshifting the Ipsilateral Proximal Femur May Provide Satisfactory Reconstruction of Periacetabular Pelvic Bone Defects After Tumor Resection

BACKGROUND

Pelvic ring reconstruction after resection of pelvic malignancies or aggressive benign tumors remains challenging, especially when the tumor invades periacetabular bone, resulting in a Type II resection as classified by Enneking and Dunham (removal of part or all of the acetabulum). Although numerous treatment approaches are in use, none is clearly superior to the others. An alternative involving use of the ipsilateral proximal femur as an autograft has not been well characterized, so we present our preliminary experience with this approach.

QUESTIONS/PURPOSES

(1) What were the oncologic outcomes after using an ipsilateral proximal femur autograft for reconstruction after Type II pelvic resection in a small series of patients who underwent this reconstructive approach? (2) What were the Musculoskeletal Tumor Society (MSTS) scores after this reconstruction? (3) What complications were observed?

METHODS

Between October 2006 and May 2016, we treated 67 patients with Type II malignant or aggressive benign tumors of the ilium. Of those, we used an ipsilateral proximal femur and a prosthesis as a reconstruction method for 11 patients with pelvic tumors. In general, we performed this approach in young or middle-aged patients with primary malignant or aggressive benign tumors involving pelvic area II and in whom the tumor did not invade the hip. The method used for resection of pelvic tumors included osteotomy of the femoral shaft, harvesting the proximal femur as a graft. The length of the femoral graft was determined by the extent of the pelvic defect. The proper placement was selected after a comparison of the proximal femur and the pelvic defect. A curved reconstruction plate and cancellous bone screws were used for pelvic fixation. The operative duration and total blood loss were recorded. Of the 11 patients who underwent this approach, all but one had at least 2 years of followup unless death occurred earlier, and all but one have been seen within the last year for evaluation. Functional outcomes were assessed using the MSTS scoring system. Local recurrence, metastases, and deaths were recorded as were complications including infection, bone nonunion, mechanical failure and sciatic nerve palsy.

RESULTS

The followup was a mean of 37 months (range, 13-96 months). One patient was lost to followup. Three patients died of disease owing to local recurrence or lung metastasis. The other seven patients lived without evidence of tumor. The main complications included mechanical failure in two patients, nonunion in one patient, infection in two patients, and sciatic nerve palsy in one patient. The median MSTS function score was 70% (21 of 30 points; range, 11-25 points).

CONCLUSIONS

Our preliminary results show that this technique of using the ipsilateral proximal femur may be an alternative method for reconstruction of pelvic bone defects after tumor resection. Even with this short followup, complications were common, but short-term function appears to be comparable to studies of other options. Longer term followup with more patients is necessary to confirm our results.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Is a Modular Pedicle-hemipelvic Endoprosthesis Durable at Short Term in Patients Undergoing Enneking Type I + II Tumor Resections With or Without Sacroiliac Involvement?

BACKGROUND

Functional reconstruction after Enneking Type I + II resections of the pelvis (those involving both the ilium and the acetabulum) is challenging, especially if resection of part of the sacrum is included. To assess the clinical outcomes of a newly designed modular pedicle-hemipelvic endoprosthesis, we performed a preliminary retrospective study on its clinical use in a small group of patients.

QUESTIONS/PURPOSES

The purposes of this study were (1) to evaluate in a small case series whether the new endoprosthesis restored lower limb function and lumbopelvic stability in the short term; (2) to identify the complications associated with use of the new prosthesis; and (3) to assess the 5-year cumulative survival, the cumulative incidence of a major postoperative event, and the cumulative incidence of implant failure in this group of patients.

METHODS

Between August 2012 and August 2014, our center performed 274 internal hemipelvectomies for oncologic indications. Among these, 20 were treated with the new endoprosthesis, which was designed for fixation both to the residual sacrum as well as the lumbar spine. An earlier version of the device had been removed from the market because of an unacceptable risk of serious complications. All of the 20 tumors were sarcomas necessitating en bloc resection. The implant is modular and can meet the different-sized defects in each patient. The general indication for use of the new implant was a total acetabular defect with extensive iliac involvement or total loss of the sacroiliac joint and/or hemisacrum. All 20 patients were followed up for a minimum of 24 months or until death in those patients who survived < 2 years (median, 36 months; range, 6-60 months). The clinical data were retrieved from the database and the study endpoints (function according to the Musculoskeletal Tumor Society [MSTS] score, complications, and survivorship of patients and implants) were ascertained by chart review. Lumbopelvic stability was defined as an excellent or good rating according to the International Society of Limb Salvage radiologic implant evaluation system. The cumulative survival of patients was estimated using the Kaplan-Meier approach. The cumulative incidence of major postoperative events including local recurrence, metastasis, and reoperation was estimated using a competing events analysis; the cumulative incidence of implant failure, including mechanical failure or deep infection, in patients who underwent reoperation was also estimated using a competing events analysis.

RESULTS

In the 16 patients who survived > 12 months, the median MSTS score was 19 of 30 (range, 5-26). Radiographic assessments demonstrated lumbopelvic stability in all of the 16 patients. Twelve of 20 patients developed postoperative complications, primarily including deep infection (one), hip dislocation (two), and local recurrence (three). Major revision surgery was performed in five of 20 patients. The estimated 5-year Kaplan-Meier patient survival rate was 69% (95% confidence interval [CI], 59%-79%), whereas the cumulative incidence of major postoperative events and implant failure using the competing risk estimator was 42% (95% CI, 23%-60%) and 15% (95% CI, 4%-34%) at 5 years, respectively.

CONCLUSIONS

Preliminary results with hemipelvic reconstruction using this new endoprosthesis achieved fair functional results and the complications that were observed appeared comparable to other reconstruction options at short-term followup. Longer-term surveillance is called for to see whether this implant will be durable compared with other available reconstructive alternatives such as a custom-made megaendoprosthesis or an autograft/allograft-prosthetic composite.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

En bloc resection of pelvic sarcomas with sacral invasion: a classification of surgical approaches and outcomes

Aims

The sacrum is frequently invaded by a pelvic tumour. The aim of this study was to review our experience of treating this group of patients and to identify the feasibility of a new surgical classification in the management of these tumours.

Patients and Methods

We reviewed 141 patients who, between 2005 and 2014, had undergone surgical excision of a pelvic tumour with invasion of the sacrum. In a new classification, pelvisacral (Ps) I, II, and III resections refer to a sagittal osteotomy through the ipsilateral wing of the sacrum, through the sacral midline, or lateral to the contralateral sacral foramina, respectively. A Ps a resection describes a pelvic osteotomy through the ilium and a Ps b resection describes a concurrent resection of the acetabulum with osteotomies performed through the pubis and ischium or the pubic symphysis. Within each type, surgical approaches were standardized to guide resection of the tumour.

Results

The mean operating time was 5.2 hours (sd 1.7) and the mean intraoperative blood loss was 1895 ml (sd 1070). Adequate margins were achieved in 112 (79.4%) of 141 patients. Nonetheless, 30 patients (21.3%) had local recurrence. The mean Musculoskeletal Tumor Society (MSTS93) lower-limb function score was 68% (sd 19; 17 to 100). According to the proposed classification, 92 patients (65%) underwent a Ps I resection, 33 patients (23%) a Ps II resection, and 16 (11%) patients a Ps III resection. Overall, 82 (58%) patients underwent a Ps a resection and 59 (42%) patient a Ps b resections. The new classification predicted surgical outcome.

Conclusion

We propose a comprehensive classification of surgical approaches for tumours of the pelvis with sacral invasion. Analysis showed that this classification helped in the surgical management of such patients and had predictive value for surgical outcomes. Cite this article: Bone Joint J 2018;100-B:798-805.

Supplying osteogenesis to dead bone using an osteogenic matrix cell sheet

PURPOSE

To evaluate whether osteogenic matrix cell sheets can supply osteogenesis to dead bone.

METHODS

Femur bone fragments (5 mm in length) were obtained from Fisher 344 rats and irradiated by a single exposure of 60 Gy to produce bones that were no longer viable. Osteogenic matrix cell sheets were created from rat bone marrow-derived stromal cells (BMSCs). After wrapping the dead bone with an osteogenic matrix cell sheet, it was subcutaneously transplanted into the back of a rat and harvested after 4 weeks. Bone formation around the dead bone was evaluated by X-ray imaging and histology. Alkaline phosphatase (ALP) and osteocalcin (OC) mRNA expression levels were measured to confirm osteogenesis of the transplanted bone. The contribution of donor cells to bone formation was assessed using the Sry gene and PKH26.

RESULTS

After the cell sheet was transplanted together with dead bone, X-ray images showed abundant calcification around the dead bone. In contrast, no newly formed bone was seen in samples that were transplanted without the cell sheet. Histological sections also showed newly formed bone around dead bone in samples transplanted with the cell sheet, whereas many empty lacunae and no newly formed bone were observed in samples transplanted without the cell sheet. ALP and OC mRNA expression levels were significantly higher in dead bones transplanted with cell sheets than in those without a cell sheet (P < 0.01). Sry gene expression and cells derived from cell sheets labeled with PKH26 were detected in samples transplanted with a cell sheet, indicating survival of donor cells after transplantation.

CONCLUSION

Our study indicates that osteogenic matrix cell sheet transplantation can supply osteogenesis to dead bone.

Clinical, functional and radiological outcomes of extracorporeal irradiation in limb salvage surgery for bone tumours

AIMS

We present a retrospective review of patients treated with extracorporeally irradiated allografts for primary and secondary bone tumours with the mid- and long-term survivorship and the functional and radiographic outcomes.

PATIENTS AND METHODS

A total of 113 of 116 (97.4%) patients who were treated with extracorporeally irradiated allografts between 1996 and 2014 were followed up. Forms of treatment included reconstructions, prostheses and composite reconstructions, both with and without vascularised grafts. Survivorship was determined by the Kaplan-Meier method. Clinical outcomes were assessed using the Musculoskeletal Tumor Society (MSTS) scoring system, the Toronto Extremity Salvage Score (TESS) and Quality of Life-C30 (QLQ-30) measures. Radiographic outcomes were assessed using the International Society of Limb Salvage (ISOLS) radiographic scoring system.

RESULTS

There were 61 (54%) men with a mean age of 22 years (6 to 70) and 52 (46%) women with a mean age of 26 years (3 to 85). There were 23 deaths. The five-year patient survivorship was 82.3% and the ten-year patient survivorship was 79.6%. The mean follow-up of the 90 surviving patients was 80.3 months (2 to 207). At the last follow-up, 105 allografts (92.9%) were still in place or had been at the time of death; eight (7%) had failed due to infection, local recurrence or fracture. Outcome scores were comparable with or superior to those in previous studies. The mean outcome scores were: MSTS 79% (sd 8); TESS 83% (sd 19); QLQ 82% (sd 16); ISOLS 80.5% (sd 19). Pearson correlation analysis showed a strong relationship between the MSTS and ISOLS scores (r = 0.71, p < 0.001).

CONCLUSION

This study shows that extracorporeal irradiation is a versatile reconstructive technique for dealing with large defects after the resection of bone tumours with good functional and radiographic outcomes. Functional outcomes as measured by MSTS, TESS and QLQ-30 were strongly correlated to radiographic outcomes. Cite this article: Bone Joint J 2017;99-B:1681-8.

Pelvic reconstruction following resection of malignant bone tumours using a stemmed acetabular pedestal cup

Aims

Pelvic reconstruction after the resection of a tumour around the acetabulum is a challenging procedure due to the complex anatomy and biomechanics. Several pelvic endoprostheses have been introduced, but the rates of complication remain high. Our aim was to review the use of a stemmed acetabular pedestal cup in the management of these patients.

Patients and Methods

The study involved 48 patients who underwent periacetabular reconstruction using a stemmed pedestal cup (Schoellner cup; Zimmer Biomet Inc., Warsaw, Indiana) between 2000 and 2013. The indications for treatment included a primary bone tumour in 27 patients and metastatic disease in 21 patients. The mean age of the patients at the time of surgery was 52 years (16 to 83).

Results

At a median follow-up of 6.6 years (95% confidence interval 4.6 to 8.2), local control was achieved in all patients; 19 patients had died (16 of disease). Complications occurred in 19 patients (40%), of which deep infection was the most common, affecting eight patients (17%). Seven patients (15%) had a dislocation of the hip. Aseptic loosening was found in three patients (6%). Two (4%) underwent hindquarter amputation for non-oncological reasons. The risk of revision, with death being treated as a competing event, was 28% at one year, 39% at five years and 48% at ten years post-operatively. The mean Musculoskeletal Tumour Society Score at final follow-up was 71% (27% to 93%).

Conclusion

This type of reconstruction is a satisfactory option for the treatment of patients with a periacetabular tumour. There remains, however, a high rate of complication, which may be reduced by future modifications of the device such as silver coating and tripolar articulation. Cite this article: Bone Joint J 2017;99-B:841–8.

Resection of the ilium in patients with a sarcoma: should the pelvic ring be reconstructed?

AIMS

The aim of the study was to investigate the controversial issue of whether the pelvic ring should be reconstructed following resection of the sarcomas of the ilium.

PATIENTS AND METHODS

From our database, we identified 64 patients who underwent excision of a tumour involving the ilium between 1976 and 2015. A total of 35 underwent complete resection, of whom 24 were reconstructed with a non-vascularised fibula graft, and four with extracorporeal irradiation and reimplantation. A total of 29 patients had a partial resection. The mean follow-up was 9.2 years (1.1 to 25.6). Functional outcomes were assessed using the Toronto Extremity Salvation Score (TESS) at final follow-up. In all, 32 patients (50%) had a chondrosarcoma.

RESULTS

The mean TESS for all patients was 71.6% (17% to 100%). The mean TESS for those who underwent total resection with reconstruction was 72.0% (17% to 100%) and without reconstruction it was 53.3% (20% to 90%) and for those who underwent partial resection it was 76.3% (31.3% to 100%). The rate of local recurrence was 42.2% and this was more common in those treated by partial resection (p = 0.048). The risk of local recurrence was related to the margin achieved at resection.

CONCLUSIONS

Given the high rate of local recurrence following excision of a tumour from the ilium, obtaining wide surgical margins should be a priority even if this requires more aggressive surgery. In young patients, where late recurrence may occur, more radical complete resection should be considered. When total resection of the ilium is considered, reconstruction should also be considered as it confers a higher functional outcome than total resection without reconstruction. Cite this article: Bone Joint J 2017;99-B:538-43.

Pasteurized autograft reconstruction after resection of periacetabular malignant bone tumours

Background

The treatment of periacetabular malignant bone tumours is challenging. Many methods of reconstruction after internal hemipelvectomy have been reported and each method has its own limitations. The aim of this study was to evaluate the oncological and functional outcomes of pasteurized autograft reconstruction after resection of periacetabular malignant bone tumours.

Methods

Ten patients (six male, four female) with periacetabular malignant tumours, who underwent resection and reconstruction with pasteurized autograft, were retrospectively reviewed. The patients’ average age at diagnosis was 40 years (range 13–65 years). There were five patients with chondrosarcoma, three with osteosarcoma, one with Ewing’s sarcoma, and one with solitary metastatic thyroid carcinoma.

Results

At the last follow-up, seven patients were alive (six with no evidence of the primary disease and one with lung metastasis for 5 months). The three other patients died of metastasis of the primary disease with a mean survival time of 12 (range 8–17) months postoperatively. The mean follow-up time for all patients was 45 (range 8–87) months. Local recurrence rate was 10%. The mean time of bone union was 12 (range 6–21) months after the operation. The mean Musculoskeletal Tumor Society score for all living patients at the last follow-up was 70.5% (range 43.3–86.7%).

Conclusions

Reconstruction with pasteurized autograft is a feasible method for treating periacetabular malignant bone tumours, with satisfactory oncological and functional outcomes and a relatively low incidence of complications.

Extracorporeal Irradiation and Reimplantation with Total Hip Arthroplasty for Periacetabular Pelvic Resections: A Review of 9 Cases

We report the early results of nine patients with periacetabular malignancies treated with Enneking and Dunham type 2 resection and reconstruction using extracorporeally irradiated (ECI) tumour bone combined with total hip arthroplasty (THA). Diagnosis was chondrosarcoma in six patients, osteosarcoma in two patients, and metastatic renal cell carcinoma in one patient. All patients underwent surgical resection and the resected specimen was irradiated with 50 Gy in a single fraction before being prepared for reimplantation as a composite autograft. The mean follow-up was 21 months (range, 3–59). All patients were alive at latest follow-up. No local recurrence was observed. One patient serially developed three pulmonary metastases, all of which were resected. One experienced hip dislocation due to incorrect seating of an acetabular liner. This was successfully treated with revision of the liner with no further episodes of instability. There were no cases of deep infection or loss of graft. The average Musculoskeletal Tumor Society (MSTS) score was 75% (range, 57–87%). Type 2 pelvic reconstruction with ECI and THA has shown excellent early oncological and functional results in our series. Preservation of the gluteus maximus and hip abductors is important for joint stability and prevention of infection.

Osteosarcoma of the pelvis

Aims

Osteosarcoma of the pelvis is a particularly difficult tumour to treat as it often presents late, may be of considerable size and/or associated with metastases when it presents, and is frequently chondroid in origin and resistant to chemotherapy. The aim of this study was to review our experience of managing this group of patients and to identify features predictive of a poor outcome.

Patients and Methods

Between 1983 and 2014, 121 patients, (74 females and 47 males) were treated at a single hospital: 74 (61.2%) patients had a primary osteosarcoma and 47 (38.8%) had an osteosarcoma which was secondary either to Paget’s disease (22; 18.2%) or to previous pelvic irradiation (25; 20.7%). The mean age of those with a primary osteosarcoma was 29.3 years (nine to 76) and their mean follow-up 2.9 years (0 to 29). The mean age of those with a secondary sarcoma was 61.9 years (15 to 85) and their mean follow-up was one year (0 to 14). A total of 22 patients with a primary sarcoma (52.4%) and 20 of those with a secondary sarcoma (47.6%) had metastases at the time of presentation.

Results

The disease-specific survival at five years for all patients was 27.2%. For those without metastases at the time of diagnosis, the five-year survival was 32.7%. Factors associated with a poor outcome were metastases at diagnosis and secondary tumours. In primary osteosarcoma, sacral location, surgical margin and a diameter > 10 cm were associated with a poor outcome.

Conclusion

In this, the largest single series of patients with an osteosarcoma of the pelvis treated in a single hospital, those with secondary tumours and those with metastases at presentation had a particularly poor outcome. For those with a primary sarcoma, sacral location, an intralesional margin and a diameter of > 10 cm were poor prognostic indicators. Cite this article: Bone Joint J 2016;98-B:555–63.

Osteogenic Matrix Cell Sheets Facilitate Osteogenesis in Irradiated Rat Bone

Reconstruction of large bone defects after resection of malignant musculoskeletal tumors is a significant challenge in orthopedic surgery. Extracorporeal autogenous irradiated bone grafting is a treatment option for bone reconstruction. However, nonunion often occurs because the osteogenic capacity is lost by irradiation. In the present study, we established an autogenous irradiated bone graft model in the rat femur to assess whether osteogenic matrix cell sheets improve osteogenesis of the irradiated bone. Osteogenic matrix cell sheets were prepared from bone marrow-derived stromal cells and co-transplanted with irradiated bone. X-ray images at 4 weeks after transplantation showed bridging callus formation around the irradiated bone. Micro-computed tomography images at 12 weeks postoperatively showed abundant callus formation in the whole circumference of the irradiated bone. Histology showed bone union between the irradiated bone and host femur. Mechanical testing showed that the failure force at the irradiated bone site was significantly higher than in the control group. Our study indicates that osteogenic matrix cell sheet transplantation might be a powerful method to facilitate osteogenesis in irradiated bones, which may become a treatment option for reconstruction of bone defects after resection of malignant musculoskeletal tumors.