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

Obesity increases the risk of major wound complications following pelvic resection for bone sarcoma

BACKGROUND

Given the paucity of data, the objective of this study is to evaluate the association between obesity and major wound complications following pelvic bone sarcoma surgery specifically.

METHODS

Patients who underwent pelvic resection for bone sarcoma from 2005 to 2021 with a minimum 6-month follow-up were reviewed. Patients with benign tumors, primary soft tissue sarcomas, local recurrence at presentation, pelvic metastatic disease, and underweight patients were excluded. A major wound complication was defined as the need for a secondary debridement procedure. Differences in baseline demographics, surgical factors, postoperative complications, and functional outcomes were compared between obese and nonobese patients. A multivariate logistic regression was performed to identify independent risk factors for major wound complications, and a Kaplan-Meier analysis to estimate overall survival between both groups.

RESULTS

Of the 93 included patients, 21 were obese (body mass index ≥ 30 kg/m2). The obesity group had a significantly higher rate of major wound complication (52% vs. 26%, p = 0.034) and a lower Toronto Extremity Salvage Score at 1-year postoperatively (47.5 vs. 71.4, p = 0.025). Obesity was the only independent risk factor in the multivariate analysis. No differences in overall survival were demonstrated between groups.

CONCLUSIONS

Obesity is a significant risk factor for major wound complications in pelvic bone sarcoma treatment. This highlights the importance of careful perioperative optimization and wound management.

Custom three-dimensional printed implants for reconstruction of oncologic pelvic defects

The use of three-dimensional printed implants in the field of orthopedic surgery has become increasingly popular and has potentiated hip reconstruction in the setting of oncologic resections of the pelvis and acetabulum. In this review, we examine and discuss the indications and technical considerations for custom implant reconstruction of pelvic defects.

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.

Hip Transposition Can Provide Early Walking Function After Periacetabular Tumor Resection: A Multicenter Study

BACKGROUND

Reconstruction after periacetabular bone tumor resection involves important tradeoffs; large bone grafts or endoprostheses are reported to offer fair walking function in general but can be technically demanding and carry a high risk of severe complications. Conversely, hip transposition avoids implant-related risks, but stability and functional return may be less consistent. Fewer studies are available on hip transposition, which is also appealing in more resource-constrained environments, and little is known about the time course from surgery to functional return after hip transposition.

QUESTIONS/PURPOSES

(1) What is the time course of recovery of walking function after hip transposition, especially in the first 6 months? (2) What factors are associated with a greater likelihood of early functional recovery? (3) Is early (2-month) functional recovery associated with a greater likelihood of walking ability and higher Musculoskeletal Tumor Society (MSTS) scores?

METHODS

Between 2009 and 2019, six tertiary care centers in Japan treated 48 patients with internal hemipelvectomy for malignant tumors. During that time, the preferred reconstructive approach was hip transposition, and 92% (44 of 48) of our patients were treated with this procedure. Among them, 86% (38 of 44) had follow-up of at least 6 months, had no local recurrence during that time, and were included in our retrospective study. We chose 6 months as the minimum follow-up duration because the endpoints in this study pertained to early recovery rather than reconstructive durability. Hip transposition involved moving the proximal end of the femur (femoral head, resection end of the trochanteric area, and spacers such as prostheses) upward to the underside of the resected ilium or the lateral side of the sacrum if sacroiliac joint resection was performed. The end of the proximal femur was stabilized to the remaining ilium or sacrum using polyethylene tape, polyethylene terephthalate mesh, an iliotibial tract graft, or an external fixator, according to the surgeon's preference. The median age at surgery was 46 years (range 9 to 76 years), there were 23 women and 15 men, and the median follow-up duration was 17 months (range 6 to 110 months). The postoperative time course of functional recovery was assessed with a record review, the timing of functional milestones was identified (wheelchair, walker, bilateral crutches, single crutch or cane, and walking without an aid), and the MSTS score at the final follow-up was assessed. Additionally, demographic and surgical factors were reviewed, and their association with short-term functional recovery and the final functional outcome was analyzed.

RESULTS

Patients started using a walker at median postoperative day (POD) 20 (IQR 14 to 36) and with bilateral crutches at median POD 35 (IQR 20 to 57). At POD 60, which was the approximate median date of discharge, 76% (29 of 38) of patients were able to walk using bilateral crutches (the early recovery group) and 24% (nine of 38) of patients were not able to do so (the delayed recovery group). No baseline factors were different between the two groups. The early recovery group had a higher median MSTS score than the delayed recovery group: 57% (range 17% to 90%) versus 45% (13% to 57%) (p = 0.047). Moreover, more patients acquired better function (a single crutch or cane or more) in the early recovery group, with a median of 5 months (95% CI 4 to 11) than did those in the delayed recovery group (median not reached) (p = 0.0006). The HR was 15.2 (95% CI 2.5 to 93). Forty-two percent (16 of 38) underwent additional surgery for wound management.

CONCLUSION

It took patients a fair amount of time to recover walking function after hip transposition, and patients who could not walk on bilateral crutches at POD 60 seemed less likely to regain walking function and were likely to have lower MSTS scores thereafter. Wound-related complications were frequent. This method may be a realistic alternative for younger patients who have the strength for a long rehabilitation period or those who want to minimize prosthesis-related complications. Future studies with more patients are necessary to understand the risk factors associated with delayed recovery.Level of Evidence Level III, therapeutic study.

Complications and Functional Outcome Differences in Carbon Ion Radiotherapy and Surgery for Malignant Bone Tumors of the Pelvis: A Multicenter, Cohort Study

BACKGROUND

Carbon ion radiotherapy (CIRT) is an evolving treatment option for malignant pelvic tumors in patients with poor surgical indications. However, the difference in complications and functional outcomes between CIRT and surgery is poorly understood. This study compares the complications and functional outcomes of CIRT and surgery to facilitate treatment selection.

METHODS

A total of 28 patients who underwent CIRT for pelvic bone tumors while theoretically meeting the surgical resection criteria were included. Sixty-nine patients who underwent surgery for pelvic bone tumors were included as controls. Major complication rates and functional outcomes (ambulatory, pain, urination, constipation) were evaluated and compared at several time points (pretreatment, discharge, and final follow-up) between the groups.

RESULTS

Early (within 90 days) major complications were not observed in the CIRT group but occurred in 30% of the surgery group, which was statistically significant (P < 0.001). In contrast, late (after 90 days) major complications occurred more often in the CIRT group than in the surgery group (18% and 4%, respectively; P = 0.042). From pretreatment until discharge, all functional outcomes in the surgery group deteriorated (P < 0.001 for all) but did not change in the CIRT group (P = 0.77-1.00). At the final follow-up, all functional outcomes showed no significant intergroup difference (P = 0.28-0.92) due to the recovery trend in the surgery group and the deterioration trend in the CIRT group.

CONCLUSIONS

Compared with surgery, CIRT may have favorable safety and stable functional outcomes in the short-term but more late complications. Mid-term functional outcomes were similar between the groups.

Differences in hip musculoskeletal loads between limbs during daily activities in patients with 3D-printed hemipelvic reconstructions following tumor surgery

BACKGROUND

Anatomical custom-made prostheses, thanks to computer-aided design and 3D-printing technology, help improve osseointegration and reduce mechanical complications in bone reconstructions following bone tumors. A recent quantitative analysis of long-term recovery in patients with 3D-printed reconstructions following pelvic tumor surgery showed asymmetries in ground reaction forces between limbs during different motor activities, while standing very good motor performance and quality of life.

RESEARCH QUESTION

We analyzed hip contact forces and muscle forces in that cohort of six patients with an innovative custom-made reconstruction of the hemipelvis, and we tested the hypothesis that asymmetries in ground reaction forces would result in more marked differences in musculoskeletal forces.

METHODS

State-of-the-art musculoskeletal modeling in an optimization-based inverse-dynamics workflow was used to calculate hip contact forces and muscle forces during five motor activities, and the differences between limbs were statistically evaluated across the motor activity cycles and on the force peaks.

RESULTS

The musculoskeletal loads were found to be not symmetric, as hip loads were generally higher in the contralateral limb. We found significant differences in considerable portions of the motor activities cycles except squat, load symmetry indices indicating a load increase (median up to 25%) on the contralateral limb, especially during stair descent and chair rise/sit, and significantly higher values in the contralateral limb at force peaks.

SIGNIFICANCE

We confirmed the hypothesis that residual asymmetries found in ground reaction forces were amplified when hip musculoskeletal loads were investigated, reflecting a shift of the loads toward the intact limb. Despite the general trend of higher loads found in the contralateral hip, this cannot be considered a risk of overloading, as both hips supported loads in a physiological range or lower, indicating a likely optimal recovery.

LUMiC® endoprosthesis for pelvic reconstruction: A Canadian experience

BACKGROUND AND OBJECTIVES

The LUMiC® prosthesis was introduced to reduce the mechanical complications encountered with periacetabular reconstruction after pelvic tumor resection. Few have evaluated the outcomes associated with its use.

METHODS

A retrospective study from five Orthopedic Oncology Canadian centers was conducted. All patients with a LUMiC® endoprosthesis were included. Their charts were reviewed for surgical and functional outcomes.

RESULTS

A total of 16 patients were followed for 28 months (3-60). A total of 12 patients (75%) had a LUMiC® after a resection of a primary sarcoma. Mean surgical time was 555 min. Four patients (25%) had a two-stages procedure. MSTS score was 60.3 preoperatively and 54.3 postoperatively. Patients got a dual mobility bearing and the silver coated implant was used in 7 patients (43.7%). Five patients (31.3%) underwent capsular reconstruction using a fabric. Silver-coating was not found to reduce infection risk (p = 0.61) and capsuloplasty did not prevent dislocation (p = 0.6). Five patients had peroperative complications (31.3%). Eight patients (50%) had an infection including all four with two-stages surgery. Dislocation occurred in five patients (31.3%) whereas no cases of aseptic loosening were reported. A total of 10 patients (62.5%) needed a reoperation.

CONCLUSION

LUMiC® endoprosthesis provides low rates of aseptic loosening on medium-term follow-up. Infection and dislocation are common complications but we were unable to show benefits of capsuloplasty and silver-coated implants.

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.

Long-term functional recovery in patients with custom-made 3D-printed anatomical pelvic prostheses following bone tumor excision

BACKGROUND

Anatomical custom-made prostheses make it possible to reconstruct complicated bone defects following excision of bone tumors, thanks to 3D-printed technology. To date, clinical measures have been used to report clinical-functional outcome and provide evidence for the effectiveness of this new surgical approach. However, there are no studies that quantified the achievable recovery during common activities by using instrumental clinical-functional evaluation in these patients.

RESEARCH QUESTION

What is the motor performance, functional outcome and quality of life in patients with custom-made 3D-printed pelvic prostheses following bone tumor?

METHODS

To analyze motor performance, six patients performed motion analysis during five motor activities at follow-up of 32 ± 18 months. Joint angles, ground reaction forces and joint moments of the operated and contralateral limbs were compared. On-off activity of lower-limb muscles were calculated from electromyography and compared to a healthy matched population. To analyze functional outcome and quality of life, differences in measured hip abductor strength between limbs were evaluated, as well as clinical-functional scores (Harris Hip Score, Barthel Index, Musculoskeletal Tumor Society score), and quality of life (SF-36 health survey).

RESULTS

We found only slight differences in joint kinematics when comparing operated and contralateral limb. The activity of gluteal muscles was normal, while hamstrings showed out-of-phase activities. Ground reaction forces and hip moments showed asymmetries between limbs, particularly in more demanding motor activities. We found a mean difference in hip abductor strength of 48 ± 82 N between limbs, good clinical-functional scores, and quality of life scores within normative.

SIGNIFICANCE

Our study showed optimal long-term results in functional recovery, mainly achieved through recovery of the gluteal function, although minor impairments were found, which may be considered for future improvement of this innovative surgery. The effect of a more loaded contralateral limb on internal loads and long-term performance of the implant remains unknown and deserves further investigation.

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

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

Multidisciplinary Approach to Hemipelvectomy for Pelvic Sarcomas

» Pelvic sarcomas are a rare and diverse group of tumors in terms of size and histology.» Pelvic sarcomas present a treatment challenge to the orthopaedic oncologist.» The size and location of these tumors require a varied approach to resection and reconstruction, but the tumor's proximity to other internal structures within the pelvis (e.g., the bladder, the iliac vessels, and the bowel) makes extrication demanding.» The ideal treatment requires assembling a hemipelvectomy team that consists of an orthopaedic oncologist, a surgical oncologist, a urologist, a vascular surgeon, a gynecologic oncologist, a plastic and reconstructive surgeon, a dedicated anesthesia team, and a dedicated rehabilitation physical therapy team. Each member can use his or her expertise to address the individual aspects of the pelvic resection and achieve the optimal oncologic and functional outcome.

Proton Therapy for Primary Bone Malignancy of the Pelvic and Lumbar Region - Data From the Prospective Registries ProReg and KiProReg

Purpose/Objective(s)

Multimodality treatments together with local proton therapy (PT) are commonly used in unresectable primary bone malignancies in order to provide better tumor control rate while maintaining good feasibility. The aim of this study is to provide data on outcome of PT for the challenging cohort of pelvic and lumbar bone tumors.

Methods and Materials

This retrospective study includes all patients with primary bone malignancy of the pelvis and lumbar spine receiving PT in our institution between May 2013 and December 2019 enrolled in the prospective registries KiProReg and ProReg collecting information on demographics, treatment, tumor characteristics, toxicities, and outcome.

Results

Eighty-one patients were enrolled with a median age of 19.7 years (1.3–85.8). The median follow-up time was 27.5 months (1.2–83.2). The majority of patients was male (64.2%), ECOG status of 0–1 (75.2%), underwent only biopsy (50.6%), received chemotherapy (69.1%) and was assigned for definite PT (70.4%). The predominant tumor characteristics were as follows: Ewing’s sarcoma histology (58%), negative nodal involvement (97.5%) and no metastasis at diagnosis (81.5%). Median maximal diameter of tumor was 8 cm (1.4–20). LC, EFS and OS rate were 76.5, 60, and 88.1% at two years and 72.9, 45.7, and 68.9% at three years, respectively. Age over 20 years was a significant negative factor for LC, EFS, and OS. Metastatic disease at initial diagnosis affected OS and ECOG status of 2–4 affected EFS only. Regarding 17 relapsed cases (21%), isolated distant relapse was the most common failure (46.9%) followed by local failure (40.6%). Eleven out of 14 evaluable patients relapsed within high-dose region of radiotherapy. Acute grade 3–4 toxicity was found in 41 patients (50.6%) and all toxicities were manageable. Late grade 3 toxicity was reported in 7 patients (10.4%) without any of grade 4. Most common higher grade acute and late side effects concerned hematologic and musculoskeletal toxicity.

Conclusion

Proton therapy resulted in good oncological outcomes when being part of the multimodality treatment for pelvic and lumbar primary bone malignancies. However, distant metastases and local failures within the high-dose region of radiotherapy are still a common issue. Acute and late toxicities of combined therapy were acceptable.

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.

Partial replacement of pelvis with the hip joint in osteosarcoma treatment: A case report

Introduction

and importance: Pelvic osteosarcoma is quite rare and is a challenging task for orthopedic surgeons. This aim of this study is to present the first case report using customized 3D-printed prosthesis in Vietnam.

Case presentation

57-year-old male was diagnosed with pelvic osteosarcoma. After neoadjuvant chemotherapy, we did limb-salvage surgery after partial pelvic resection. He had to undergo another surgery due to an infection complication that exposed part of the prosthesis. At 6 months follow-up, the patient's overall status was stable. VAS score when moving is 2/10. He can walk with one crutch. Patient is still being followed up and treated.

Clinincal discussion

Management of pelvic osteosarcoma remains a challenging task for orthopedic surgeons. Advancements in customized 3D-printed prosthesis have been applied in treatment of pelvic osteosarcoma. Despite the complications, the results are promising. We believe that this is a new and innovative route in surgery of pelvic osteosarcoma.

Conclusion

Using customized 3D-printed prosthesis is a good way for management of pelvic osteosarcoma.

•

Osteosarcoma of pelvis is not common, account for 4–10% of all bone cancer.

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Pelvis connect the lower limb with body by hip joint and support the intraabdominal organ.

•

It is very difficult to preserve the pelvis after wide resection.

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Custom made 3D printed implant give us a chance to restore the pelvis anatomically and functionally.

Patient-Specific Implants for Pelvic Tumor Resections

Introduction Limb salvage surgery for periacetabular malignancies is technically demanding and associated with a considerable likelihood of postoperative complications and surgical revision. Reconstruction using custom-made implants represents the treatment of choice. This study was conducted to analyze treatment outcomes of custom-made implants in a single orthopaedic tumor center. Patients and Methods Twenty patients with a histologically verified periacetabular malignancy and a median follow up time of 5 (1-17) years were included. Results The median number of revision surgeries per patient was 1.5 (0-7). Complications were dislocations in 3 patients, aseptic loosening in 4 patients, deep infections in 9 patients, thromboembolic events in 5 patients and sciatic nerve lesions in 4 patients. Overall survival was 77% after one year, 69% after two years and 46% after five years. Median Harris Hip Score was 81 (37-92) points at last follow up. Conclusion Although internal hemipelvectomy and reconstruction using custom-made implants is linked with a high risk of postoperative complications, good functional outcomes can be regularly achieved. This information may help treating surgeons to find adequate indications, as eligible patients need to be critically selected and integrated into the decision-making process.

Remaining spine deformity after revision surgery for pelvic reconstruction and spinopelvic fixation: illustrative case

BACKGROUND

Pelvic deformity after resection of malignant pelvic tumors causes scoliosis. Although the central sacral vertical line (CSVL) is often used to evaluate the coronal alignment and determine the treatment strategy for scoliosis, it is not clear whether the CSVL is a suitable coronal reference axis in cases with pelvic deformity. This report proposes a new coronal reference axis for use in cases with pelvic deformity and discusses the pathologies of spinal deformity remaining after revision surgery.

OBSERVATIONS

A 14-year-old boy who had undergone internal hemipelvectomy and pelvic ring reconstruction 2 years prior was referred to our hospital with severe back pain. His physical and radiographic examinations revealed severe scoliosis with pelvic deformity. The authors planned a surgical strategy based on the CSVL and performed pelvic ring reconstruction using free vascularized fibula graft and spinopelvic fixation from L5 to the pelvis. After the procedure, although the patient’s back pain was relieved, his scoliosis persisted. At the latest follow-up, his spinal deformity correction was acceptable with corset bracing. Therefore, the authors did not perform additional surgeries.

LESSONS

The CSVL may not be appropriate for evaluating coronal alignment in cases with pelvic deformity. Accurate preoperative planning is required to correct spinal deformities with pelvic deformity.

Pelvic bone tumor resection: post-operative imaging

The anatomic extent of a pelvic bone tumor and the need for reconstruction dictate the type of pelvic resection (limb salvage pelvic resection or amputation). If a pelvic bone tumor resection involves two or more critical anatomic structures (the sciatic nerve, femoral neurovascular bundle or the hip joint), then reasonable functional recovery after limb salvage is less likely and amputation should be considered. Both limb salvage and amputation approaches to the pelvis are technically arduous surgeries with significant associated morbidity and complications. As such, imaging plays an important role in the post-operative management of patients who have undergone pelvic bone tumor resection. In this article, we will review optimal imaging techniques as well as the expected post-operative appearance after pelvic bone tumor resection and important complications including infection, tumor recurrence, and complications related to complex soft tissue and osseous reconstruction.

Does Adding Femoral Lengthening at the Time of Rotation Hip Transposition After Periacetabular Tumor Resection Allow for Restoration of Limb Length and Function? Interim Results of a Modified Hip Transposition Procedure

BACKGROUND

Reconstruction after pelvic tumor resection of the acetabulum is challenging. Previous methods of hip transposition after acetabular resection have the advantages of reducing wound complications and infections of the allograft or metal endoprosthesis but were associated with substantial limb length discrepancy. We therefore developed a modification of this procedure, rotation hip transposition after femur lengthening, to address limb length, and we wished to evaluate its effectiveness in terms of complications and functional outcomes.

QUESTIONS/PURPOSES

In this study, we asked: (1) What were the Musculoskeletal Tumor Society scores after this reconstruction method was used? (2) What complications occurred after this reconstruction method was used? (3) What proportion of patients achieved solid arthrodesis (as opposed to pseudarthrosis) with the sacrum and solid union of the femur? (4) What were the results with respect to limb length after a minimum follow-up of 2 years?

METHODS

From 2011 to 2017, 83 patients with an aggressive benign or primary malignant tumor involving the acetabulum were treated in our institution. Of those, 23% (19 of 83) were treated with rotation hip transposition after femur lengthening and were considered for this retrospective study; 15 were available at a minimum follow-up of 2 years (median [range], 49 months [24 to 97 months]), and four died of lung metastases before 2 years. No patients were lost to follow-up before 2 years. During the period in question, the general indications for this approach were primary nonmetastatic malignant bone tumor or a locally aggressive benign bone tumor that could not be treated adequately with curettage. There were seven men and 12 women with a median age of 43 years. Nine patients underwent Zones I + II resection, eight patients had Zones I + II + III resection, and two received Zones II + III resection. After tumor resection, rotation hip transposition after femur lengthening reconstruction was performed, which included two steps. The first step was to lengthen the femur with the insertion of an allograft. Two methods were used to achieve limb lengthening: a "Z" osteotomy and a transverse osteotomy. The second step was to take the hip transposition and rotate the femoral head posteriorly 10° to 20°. The median (range) operative time was 510 minutes (330 to 925 minutes). The median intraoperative blood loss was 4000 mL (1800 to 7000 mL). We performed a chart review on the 15 available patients for clinical and radiographic assessment of functional outcomes and complications. Arthrodesis and leg length discrepancy were evaluated radiographically.

RESULTS

The median (range) Musculoskeletal Tumor Society score was 21 points (17 to 30). Eleven of 19 patients developed procedure-related complications, including six patients with allograft nonunion, two with deep infection, two with delayed skin healing, and one with a hematoma. Two patients had minor additional surgical interventions without the removal of any implants. Local recurrences developed in four patients, and all four died of disease. All seven patients treated with a Z osteotomy had bone union. Among the eight patients with transverse osteotomy, bone union did not occur in six patients. After hip transposition, stable iliofemoral arthrodesis was achieved in seven patients. Pseudarthrosis developed in the remaining eight patients. The median (range) lower limb length discrepancy at the last follow-up visit or death was 8 mm (1 to 42 mm).

CONCLUSION

Although complex and challenging, rotation hip transposition after femur lengthening reconstruction with a Z osteotomy provides acceptable functional outcomes with complications that are within expectations for resection of pelvic tumors involving the acetabulum. Because of the magnitude and complexity of this technique, we believe it should be used primarily for patients with a favorable prognosis, both locally and systemically. This innovative procedure may be useful to other surgeons if larger numbers of patients and longer-term follow-up confirm our results.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Three-dimensional printing-based personalized limb salvage and reconstruction treatment of pelvic tumors

BACKGROUND AND OBJECTIVES

The treatment of pelvic tumors is widely recognized to be challenging. The purpose of this study was to evaluate the efficacy of personalized three-dimensional (3D) printing-based limb salvage and reconstruction treatment for pelvic tumors.

METHODS

Twenty-eight pelvic tumor patients were enrolled. 3D printing lesion models and osteotomy templates were prepared for surgery planning, prosthesis design, and osteotomy assistance during surgery. 3D printing-based personalized pelvic prostheses were manufactured and used in all 28 patients. Follow-up of postoperative survival, prosthesis survival, imaging examinations, and Musculoskeletal Tumor Society (MSTS) lower limb functional scores were carried out.

RESULTS

The mean follow-up period was 32.2 months, during which 16 patients had disease-free survival, 3 survived with the disease, and 9 died. The prostheses were stable, and the mean offset of the center of rotation was 5.48 mm. The prosthesis-bone interface showed good integration. For the 19 surviving patients, the mean MSTS lower limb functional score was 23.2. Postoperative complications included superficial infection in six patients and hip dislocation in three patients.

CONCLUSIONS

Personalized 3D printing-based limb salvage and reconstruction was an effective treatment for pelvic tumors. Our patients achieved good early postoperative efficacy and functional recovery.

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.

Suicide and accidental deaths among patients with primary malignant bone tumors

Background

It has been recognized that cancer is associated with a higher risk of suicide or accidental death. Earlier studies have evidenced that patients with malignant bone tumors usually experience psychological dysfunction and physical disability following surgery, which are shared risk factors between suicidal and accidental deaths. To our knowledge, there is no large population-based study on the risk of suicide or accidental death among patients with malignant bone tumors.

Questions/purposes

This study aimed to determine whether patients with primary malignant bone tumors are at a higher risk of suicide and accidental death than the general population and to identify the demographic and tumour-related characteristics and type of surgery associated with a higher risk of suicide and accidental death among these patients.

Methods

Overall, 50,817 patients diagnosed with primary malignant bone tumors between 1973 and 1975 were identified from the Surveillance, Epidemiology, and End Results database. The standardised mortality ratio (SMR) was calculated based on the general population's mortality data, gathered by the National Center for Health Statistics. The Cox regression model was developed to determine risk factors associated with a higher risk of suicide and accidental death.

Results

Patients with primary malignant bone tumors had a higher risk of suicide and accidental death than the general population in the United States (US) (SMR = 2.17; 95% confidence interval (CI) [1.80-2.62] and SMR = 1.73; 95% CI [1.54-1.95]). Compared with limb salvage, amputation significantly increased the risk of suicide (SMR = 3.99; 95% CI [2.52-6.34], hazard ratio (HR) = 2.32; 95% CI [1.31-4.09]; P < 0.01) but did not increase the risk of accidental death (SMR = 1.61; 95% CI [1.07-2.42], HR = 1.11; 95% CI [0.71-1.74]; P = 0.65). Higher suicide risk was observed among older patients whose age at diagnosis was more than 60 years (HR = 4.04; 95% CI [1.98-8.26]; P < 0.001), males (HR = 3.48; 95% CI [2.16-5.62]; P < 0.001), and whites (HR = 3.71; 95% CI [1.17-11.73]; P < 0.001). The risk of suicide and accidental death was highest in the first year after diagnosis (SMR = 2.95; 95% CI [1.86-4.69] and SMR = 2.02; 95% CI [1.48-2.74]).

Conclusion

We first reported that patients with primary malignant bone tumors had a higher risk of suicide and accidental death than the general US population. Therefore, clinicians should pay more attention to the psychological status, physical function, and cognitive level of these survivors.

Artificial Intelligence (AI) Assisted CT/MRI Image Fusion Technique in Preoperative Evaluation of a Pelvic Bone Osteosarcoma

Surgeries of pelvic bone tumors are very challenging due to the complexity of anatomical structures and the irregular bone shape. CT and MRI are used in clinic for tumor evaluation, each with its own advantages and shortcomings. Combining the data of both CT and MRI images would take advantage of the merits of both images and provide better model for preoperative evaluation. We utilized an artificial intelligence (AI)-assisted CT/MRI image fusion technique and built a personalized 3-D model for preoperative tumor margin assessment. A young female patient with pelvic osteosarcoma was evaluated with our novel image fusion 3-D model in comparison with the 3-D model based solely on CT images. The fusion image model showed more detailed anatomical information and discovered multiple emboli within veins which were previously neglected. The discovery of emboli implied abysmal prognosis and discouraged any attempts for complex reconstruction after tumor resection. Based on the experience with this pelvic osteosarcoma, we believe that our image fusion model can be very informative with bone tumors. Though further validation with a large number of clinical cases is required, we propose that our model has the potential to benefit the clinic in the preoperative evaluation of bone tumors.

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.

The long-term outcomes of modified Harrington procedure using antegrade pins for periacetabular metastasis and haematological diseases

AIMS

The aim of this study was to present the long-term surgical outcomes, complications, implant survival, and causes of implant failure in patients treated with the modified Harrington procedure using antegrade large diameter pins.

PATIENTS AND METHODS

A cohort of 50 consecutive patients who underwent the modified Harrington procedure for periacetabular metastasis or haematological malignancy between January 1996 and April 2018 were studied. The median follow-up time for all survivors was 3.2 years (interquartile range 0.9 to 7.6 years).

RESULTS

The five-year overall survival rate was 33% for all the patients. However, implant survival rates were 100% and 46% at five and ten years, respectively. Eight patients survived beyond five years. There was no immediate perioperative mortality or complications. A total of 15 late complications occurred in 11 patients (22%). Five patients (10%) required further surgery to treat complications. The most frequent complication was pin breakage without evidence of acetabular loosening (6%). Two patients (4%) underwent revision for aseptic loosening at 6.5 and 8.9 years after surgery. Ambulatory status and pain level were improved in 83% and 89%, respectively.

CONCLUSION

The modified Harrington procedure for acetabular destruction has low complication rates, good functional outcome, and improved pain relief in selected patients Cite this article: Bone Joint J 2019;101-B:1557-1562.

Functional Outcome Measurement in Patients with Lower-Extremity Soft Tissue Sarcoma: A Systematic Literature Review

Background

The importance of functional outcome (FO) in the treatment of patients with extremity soft tissue sarcoma (STS) has been increasingly recognized in the last three decades. This systematic review aimed to investigate how FO is measured in surgically treated lower-extremity STS patients.

Methods

A systematic search of PubMed, Web of Science, and Scopus was performed based on the PRISMA guidelines. The methodologic quality of the publications was measured using the MINORS tool. The results from the included studies examining measurement types, measures, and time of FO measurement were compiled. The FO pooled mean and standard deviation were calculated as a weighted average for the groups. The validity of the applied measures is reported.

Results

The literature search found 3461 publications, 37 of which met the inclusion criteria. The measurement types used were clinician-reported outcomes (n = 27), patient-reported outcomes (n = 20), and observer-reported outcomes (n = 2). The most frequently used measures were the Toronto Extremity Salvage Score (TESS) (n = 16) and the Musculoskeletal Tumor Society (MSTS) score 1993 (n = 12). The postoperative FO was relatively good. The pooled mean TESS and MSTS 1993 scores were respectively 83.3 and 86.2 (out of 100). Of the 10 previously reported measures, 3 provide validated FO scores. The methodologic quality of publications was generally low.

Conclusions

Based on this systematic review, several different methods exist for assessing FO in patients with lower-extremity sarcoma. The most frequently used measure is a validated TESS. The postoperative FO of patients with lower-extremity STS seems to increase to the preoperative baseline level during long-term follow-up evaluation.

AP2a enhanced the osteogenic differentiation of mesenchymal stem cells by inhibiting the formation of YAP/RUNX2 complex and BARX1 transcription

Objectives

Bone regeneration by bone tissue engineering is a therapeutic option for bone defects. Improving the osteogenic differentiation of mesenchymal stem cells (MSCs) is essential for successful bone regeneration. We previously showed that AP2a enhances the osteogenic differentiation in MSCs. The present study investigated the mechanism of how AP2a regulates the direct differentiation.

Materials and methods

Co‐immunoprecipitation and ChIP assays were carried out to investigate the underlying mechanism in MSCs differentiation. The osteogenic differentiation potential was determined by mineralization ability and the expression of osteogenic marker in vitro and the in vivo bone‐like tissue generation in nude mice.

Results

We show that AP2a can compete with RUNX2, a key transcription factor in osteogenic differentiation, to recruit YAP and release the inhibition of RUNX2 activity from YAP by forming YAP‐AP2a protein complex. YAP‐AP2a protein complex also interacts with the BARX1 promoter through AP2a, inhibit the transcription of BARX1. Moreover, BARX1 inhibits osteogenic differentiation of MSCs.

Conclusions

Our discoveries revealed that AP2a may regulate the osteogenic differentiation in an indirect way through competing with RUNX2 to relieve the RUNX2 activity which inhibited by YAP, and also in a direct way via targeting the BARX1 and directly repressed its transcription. Thus, our discoveries shed new light on the mechanism of direct differentiation of MSCs and provide candidate targets for improving the osteogenic differentiation and enhancing bone tissue regeneration.