The surgical treatment of pelvic bone metastases

Periacetabular metastases: Proposed extension of the Harrington classification

Objectives

To describe the functional outcomes, complications, and reconstruction types in patients with periacetabular metastases and to propose an extension of the Harrington classification.

Methods

Twenty-eight patients (13 males, 15 females) with a mean age of 63.8 ± 15.5 years presented with periacetabular metastases from January 2010 to December 2021. The periacetabular metastases were graded according to Harrington's classification, with four additional categories introduced: A) joint involvement, B) Enneking zone 1 involvement, C) pathological acetabular fracture, and X) none of the above. All patients underwent surgery at a single national referral center.

Results

Based on the Harrington classification, the acetabular destruction results were as follows: Class 1, two cases (7 %); Class 2, eight cases (29 %); Class 3, 17 cases (61 %); and Class 4, one case (3 %). The results for the additional categories were: A, five cases (18 %); B, five cases (18 %); C, seven cases (25 %); and X, 11 cases (39 %). The most frequent type of reconstruction was total hip prosthesis with a reinforcement ring. Four patients (14 %) required reintervention. After a mean follow-up of 43 ± 45 months (range 2-144), seven patients (25 %) could walk unaided, 16 (57 %) required assistance, and five (18 %) could not walk. Three patients (11 %) died before the third postoperative month.

Conclusion

Most patients in this study achieved functional outcomes that allowed ambulation. The type of reconstruction was determined by the classification of the bone defect. We propose extending Harrington's classification to include the four additional categories introduced in this study.

Outcomes of Palliative Hemipelvectomy in Comprehensive Cancer Center Patients with Metastatic Cancer: Retrospective Study

BACKGROUND

Hemipelvectomy is a complex operation that is usually performed with curative intent. It is rarely performed for palliation in patients with advanced cancer, and its efficacy in achieving palliation is unknown.

STUDY DESIGN

Retrospective review of 10 patients with stage IV cancer who underwent palliative hemipelvectomy at a comprehensive cancer center.

RESULTS

Median age of the cohort was 60 years; 7 patients were male. Five patients had previous radiotherapy to the pelvic bone. Hemipelvectomies involved 1 to 2 Enneking-Dunham pelvic zones in 6 patients and 3 to 4 zones in 4 patients. Six patients had Clavien-Dindo complication of grade 3 or higher. Median overall survival was 6.6 months. Surgical complication resulted in death in 3 patients. At their 3-month follow-up, 5 of 8 living patients had increased narcotic requirements, and 4 of 7 with data had reduced pain (1 of whom was using high-dose intravenous narcotics). No patients experienced functional improvement, and at 6 months, 4 of the 5 who had been ambulatory preoperatively were less mobile. Outcomes tended to be better among patients whose resections were less extensive or limited to zone 3 (anterior pelvis).

CONCLUSIONS

Palliative-intent hemipelvectomy provided palliation in a minority of patients, did not improve function, and had high morbidity and mortality. Patients with small anterior pelvic tumor may benefit from palliative hemipelvectomy; for others, less invasive approaches should be considered whenever feasible.

Percutaneous Cementation for Improvement of Pain and Function for Osteolytic Pelvic Metastasis: A Systematic Review

INTRODUCTION

Pelvic metastasis is a common presentation among patients presenting with skeletal metastasis. Image-guided percutaneous cementation of these lesions is becoming increasingly popular for the treatment of these lesions. The objective of this study was to conduct a systematic review that investigates clinical outcomes after percutaneous cementation for pelvic metastasis.

METHODS

A systematic review was registered with International Prospective Register of Systematic Reviews and performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed, SCOPUS, and Ovid MEDLINE databases. All level I to IV clinical studies published in the English language investigating the clinical outcomes after percutaneous cementation for pelvic metastasis were included.

RESULTS

Fourteen studies with 579 patients (278 men, 301 women) and 631 metastatic pelvic lesions were included in the study. The mean follow-up range was 0.7 to 26.4 months. Percutaneous cementation alone was performed in 441 patients (76.2%). Supplemental ablative procedures were performed in 77 patients (13.3%), and supplemental internal fixation using cannulated screws was performed in 107 patients (18.5%). Twelve studies with 430 patients (74.2%) reported pain-related and/or functional outcome scores, of which all studies reported overall clinically notable improvement at short-term follow-up. All studies reported periprocedural complications. Local cement leakage was the most common complication (162/631 lesions, 25.7%) followed by transient local pain (25/579 patients, 4.3%). There were no reported cases of major complications. Seven patients (1.2%) underwent re-intervention for persistent symptoms.

CONCLUSIONS

Percutaneous cementation may be an effective method for treating pain and function related to pelvic metastasis. The most common complication was cement leakage surrounding the lesion. The rates of major complications were low, and most complications appeared minor and transient. Additional prospective studies are needed to further assess the efficacy of this procedure.

LEVEL OF EVIDENCE

IV, systematic review of level I to IV therapeutic studies.

Assessing Pain and Functional Outcomes of Percutaneous Stabilization of Metastatic Pelvic Lesions via Photodynamic Nails: A Bi-Institutional Investigation of Orthopaedic Outcomes

Background

Minimally invasive surgical interventions for metastatic invasion of the pelvis have become more prevalent and varied. Our group hypothesized that the use of percutaneous photodynamic nails (PDNs) would result in decreased pain, improved functional outcomes and level of ambulation, and decreased use of opioid pain medication.

Methods

We performed a retrospective chart review of patients with metastatic pelvic bone disease undergoing stabilization with PDNs (IlluminOss Medical) at 2 institutions. Functional outcome measures assessed include the Combined Pain and Ambulatory Function (CPAF), Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function, and PROMIS Global Health-Physical. Pain was assessed using a visual analog scale (VAS). Outcomes were assessed preoperatively and at 6 weeks, 3 months, 6 months, and 1 year following surgery.

Results

A total of 39 patients treated with PDNs were included. No cases of surgical site infection or implant failure were identified. The median pain VAS score decreased from 8 preoperatively to 0 at the 6-week time point (p < 0.0001). The median CPAF score improved from 5.5 points preoperatively to 7 points at the 3-month mark (p = 0.0132). A significant improvement in physical function was seen at 6 months in the PROMIS Physical Function (p = 0.02) and at both 6 months (p = 0.01) and 1 year (p < 0.01) for the PROMIS Global Health-Physical. The rate of patients prescribed opioid analgesia dropped from 100% preoperatively to 20% at 6 months following surgery (p < 0.001). By 6 weeks, all patients were fully weight-bearing and able to walk independently with or without assistive devices.

Conclusions

Percutaneous stabilization of metastatic periacetabular defects using PDNs is a safe and effective palliative procedure that has been shown to improve patient mobility and provide early pain relief.

Level of Evidence

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

Limb Salvage and Pelvic Reconstruction With Endoprosthesis After Pelvic Tumor Resection: A Narrative Review

Periacetabular defects following tumor resection present formidable challenges in reconstruction and continue to pose clinical difficulties. Historically, treatment approaches leaned towards hindquarter amputation; however, due to associated morbidities and functional limitations, limb-sparing procedures gained prominence in the 1980s. Nevertheless, the intricacies of pelvic anatomy and the imperative of achieving wide surgical margins while preserving essential structures make pelvic tumor resection and subsequent reconstruction inherently complex. Various reconstruction modalities have been explored, including non-vascularized fibular grafts and prosthetic implants. Among these options, the LUMiC® endoprosthesis stands out as a promising solution for pelvic reconstruction post-tumor resection. Characterized by a modular design featuring a hydroxyapatite-coated stem and acetabular cup, this device has shown favorable implant survival rates in studies, despite encountering complications primarily associated with soft tissue failure, dislocation, and infection. Notably, the incidence of complications varies across studies. The Henderson classification system delineates these complications, encompassing soft tissue issues, aseptic loosening, periprosthetic fractures, infections, and tumor recurrence. Despite the encouraging functional outcomes associated with the LUMiC® endoprosthesis, it is not immune to limitations. Concerns persist regarding complications such as dislocation and infection, underscoring the imperative for further research to evaluate the long-term durability and reliability of this reconstructive approach. Moreover, advancements in surgical techniques, perioperative management, and the advent of navigation-assisted procedures hold promise for enhancing outcomes and mitigating complication rates in pelvic reconstruction surgeries.

Clinical practice guidelines for full-cycle standardized management of bone health in breast cancer patients

Bone health management for breast cancer spans the entire cycle of patient care, including the prevention and treatment of bone loss caused by early breast cancer treatment, the adjuvant application of bone-modifying agents to improve prognosis, and the diagnosis and treatment of advanced bone metastases. Making good bone health management means formulating appropriate treatment strategies and dealing with adverse drug reactions, and will help to improve patients' quality of life and survival rates. The Breast Cancer Expert Committee of the National Cancer Center for Quality Control organized relevant experts to conduct an in-depth discussion on the full-cycle management of breast cancer bone health based on evidence-based medicine, and put forward reasonable suggestions to guide clinicians to better deal with health issues in bone health clinics.

Minimally invasive management of pathologic fractures of the pelvis and sacrum: Tumor ablation and fracture stabilization

BACKGROUND

Pathologic fractures of the pelvis/sacrum due to metastatic bone disease (MBD) cause pain and dysfunction due to mechanical instability of the pelvic ring. This study presents our multi-institutional experience with percutaneous stabilization of pathologic fractures and osteolytic lesions from MBD throughout the pelvic ring.

METHODS

The records of patients undergoing this procedure from 2018 to 2022 were reviewed retrospectively from two institutions. Surgical data and functional outcomes were recorded.

RESULTS

Fifty-six patients underwent percutaneous stabilization, with a median operative duration of 119 min (interquartile range [IQR]: 92.8, 167) and median estimated blood loss of 50 mL (IQR: 20, 100). The median length of stay was 3 days (IQR: 1, 6), and 69.6% (n = 39) of patients were discharged home. Early complications included one partial lumbosacral plexus injury, three acute kidney injuries, and one case of intra-articular cement extravasation. Late complications included two infections and one revision stabilization procedure for hardware failure. Mean Eastern Cooperative Oncology Group (ECOG) scores improved from 3.02 (SD 0.8) preoperatively to 1.86 (SD 1.1) postoperatively (p < 0.001). Ambulatory status also improved (p < 0.001).

CONCLUSIONS

Percutaneous stabilization of pathologic fractures and osteolytic defects of the pelvis and sacrum is a procedure that improves patient function, ambulatory status and is associated with a limited complication profile.

Initial experience, feasibility, and technical development with an electromagnetic navigation assistance in percutaneous pelvic bone cementoplasty: retrospective analysis

OBJECTIVES

To assess the feasibility and technical outcomes of pelvic bone cementoplasty using an electromagnetic navigation system (EMNS) in standard practice.

MATERIALS AND METHODS

Monocentric retrospective study of all consecutive patients treated with cementoplasty or reinforced cementoplasty of the pelvic bone with EMNS-assisted procedures. The endpoints were periprocedural adverse events, needle repositioning rates, procedure duration, and radiation exposure.

RESULTS

A detailed description of the technical steps is provided. Thirty-three patients (68 years ± 10) were treated between February 2016 and February 2020. Needle repositioning was required for 1/33 patients (3%). The main minor technical adverse event was soft tissue PMMA cement leaks. No major adverse event was noted. The median number of CT acquisitions throughout the procedures was 4 (range: 2 to 8). Radiation exposure and mean procedure duration are provided.

CONCLUSION

Electromagnetic navigation system-assisted percutaneous interventions for the pelvic bone are feasible and lead to low rates of minor technical adverse events and needle repositioning. Procedure duration and radiation exposure were low.

KEY POINTS

• Initial experience for 33 patients treated with an electromagnetic navigation assistance for pelvic cementoplasty shows feasibility and safety. • The use of an electromagnetic navigation system does not expose to high procedure duration or radiation exposure. • The system is efficient in assisting the radiologist for extra-axial planes in challenging approaches.

Percutaneous Ablation, Osteoplasty, Reinforcement, and Internal Fixation for Pain and Ambulatory Function in Periacetabular Osteolytic Malignancies

Background Osteolytic neoplasms to periacetabular bone frequently cause pain and fractures. Immediate recovery is integral to lifesaving ambulatory oncologic care and maintaining quality of life. Yet, open acetabular reconstructive surgeries are associated with numerous complications that delay cancer treatments. Purpose To determine the effectiveness for short- and long-term pain and ambulatory function following percutaneous ablation, osteoplasty, reinforcement, and internal fixation (AORIF) for periacetabular osteolytic neoplasm. Materials and Methods This retrospective observational study evaluated clinical data from 50 patients (mean age, 65 years ± 14 [SD]; 25 men, 25 women) with osteolytic periacetabular metastases or myeloma. The primary outcome of combined pain and ambulatory function index score (range, 1 [bedbound] through 10 [normal ambulation]) was assessed before and after AORIF at 2 weeks and then every 3 months up to 40 months (overall median follow-up, 11 months [IQR, 4-14 months]). Secondary outcomes included Eastern Cooperative Oncology Group (ECOG) score, infection, transfusion, 30-day readmission, mortality, and conversion hip arthroplasty. Serial radiographs and CT images were obtained to assess the hip joint integrity. The paired t test or Wilcoxon signed-rank test and Kaplan-Meier analysis were used to analyze data. Results Mean combined pain and ambulatory function index scores improved from 4.5 ± 2.4 to 7.8 ± 2.1 (P < .001) and median ECOG scores from 3 (IQR, 2-4) to 1 (IQR, 1-2) (P < .001) at the first 2 weeks after AORIF. Of 22 nonambulatory patients, 19 became ambulatory on their first post-AORIF visit. Pain and functional improvement were retained beyond 1 year, up to 40 months after AORIF in surviving patients. No hardware failures, surgical site infections, readmissions, or delays in care were identified following AORIF. Of 12 patients with protrusio acetabuli, one patient required a conversion hemiarthroplasty at 24 months. Conclusion The ablation, osteoplasty, reinforcement, and internal fixation, or AORIF, technique was effective for short- and long-term improvement of pain and ambulatory function in patients with periacetabular osteolytic neoplasm. © RSNA, 2023.

Axial Axis Metastasis

Axial axis metastasis remains a challenge for surgical as well as other treatment modalities, like chemotherapy, immunotherapy, and radiotherapy. It is unequivocal that surgery provides pain improvements and preservation of neurological status, but this condition remains when associated with radiotherapy and other treatment modalities. In this review, we emphasize the current forms of surgical treatment in the different regions of the spine and pelvis. The evident possibility of percutaneous treatments is related to early or late cases, and in cases in which there are greater risks and instability to conventional surgeries associated with radiotherapy and have been shown to be the appropriate option for local control of metastatic disease.

Functional and Survival Outcomes of Patients following the Harrington Procedure for Complex Acetabular Metastatic Lesions

Background: The Harrington surgical technique makes it possible to manage complex, extensive bone lesions using pins and cement to consolidate bone for acetabular cup positioning. However, it may be associated with a high reoperation rate, and the functional results of this surgery are not precisely described in the literature. Methods: In a monocentric retrospective study including all patients operated on using the Harrington procedure associated with THA between 2005 and 2020, we aimed to assess preoperative and postoperative function, reoperation-free survival, and overall survival. Results: Functional improvement was significant for Parker scores (preoperative: 3.6 ± 2.0; 6-month follow-up: 6.6 ± 3.2; 12-month follow-up: 7.6 ± 2.1) and Musculoskeletal Tumor Society (MSTS) scores (preoperative: 31.1 ± 16.2%; 6-month follow-up: 67.7 ± 30.6%; 12-month follow-up: 82.4 ± 24.0%). Of the 21 patients included, the reoperation-free survival rate was 76.1% [CI 95%: 58.1–99.7] at six and twelve months, with the main complications being pin migration (50.0%) and infection (25%). The patient overall survival rate was 76.2% [95% CI: 59.9–96.7] at six months and 61.9% [95% CI: 59.9–96.7] at 12 months. Discussion: These results underlined significant functional improvements following a conventional Harrington procedure, with acceptable reoperation rates.

Translational Strategies to Target Metastatic Bone Disease

Metastatic bone disease is a common and devastating complication to cancer, confounding treatments and recovery efforts and presenting a significant barrier to de-escalating the adverse outcomes associated with disease progression. Despite significant advances in the field, bone metastases remain presently incurable and contribute heavily to cancer-associated morbidity and mortality. Mechanisms associated with metastatic bone disease perpetuation and paralleled disruption of bone remodeling are highlighted to convey how they provide the foundation for therapeutic targets to stem disease escalation. The focus of this review aims to describe the preclinical modeling and diagnostic evaluation of metastatic bone disease as well as discuss the range of therapeutic modalities used clinically and how they may impact skeletal tissue.

Percutaneous Screw Stabilization of Non-Periacetabular Pelvic Lesions Caused by Metastatic Cancer and Multiple Myeloma

BACKGROUND

The pelvis is one of the most common locations for metastatic bone disease. While many of the publications that describe surgical treatments focus on periacetabular lesions (Enneking zone II), there is a lack of investigation into lesions in the non-periacetabular areas (zones I, III, and IV). We recently described a minimally invasive percutaneous screw application for metastatic zone-II lesions with excellent results. In the present study, we aimed to extend this approach to the other pelvic areas.

METHODS

Twenty-two consecutive patients with painful non-periacetabular pelvic metastatic cancer were included based on retrospective chart review. There were 16 women and 6 men with an average age of 60 years (range, 36 to 81 years). The most common primary cancers were multiple myeloma (7 cases) and breast (5 cases). The most common locations were the sacrum and the ilium. A pathologic fracture was identified in 15 patients. Most of the lesions were treated with multiple large-diameter screws, except for the isolated zone-III lesions. All of the procedures were completed in a standard operating room without the need for special instruments. Radiation therapy was given to 19 patients; the average dose was 15 Gy. The studied outcomes were pain and functionality as assessed by a visual analog scale (VAS) score and the Eastern Cooperative Oncology Group score (ECOG), respectively.

RESULTS

There were no surgical complications and no need for blood transfusion. The average follow-up time was 7 months (range, 0.3 to 34.0 months). Two patients died within 4 weeks of surgery due to COVID-19 infection. There was significant improvement in the postoperative VAS pain score (p < 0.0001) and the ECOG score (p < 0.05) when compared with the preoperative scores. There was no implant failure or revision surgery. Local bone-healing was observed in 12 of 14 patients (86%) who survived for >3 months after surgery.

CONCLUSIONS

Percutaneous screw application is safe and effective in the treatment of metastatic non-periacetabular pelvic lesions. Given the simplicity of the technique and the instrumentation and the tolerance for concomitant treatments, this approach is worthy of broader consideration.

LEVEL OF EVIDENCE

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

Joint-sparing Reconstruction for Extensive Periacetabular Metastases: Literature Review and a Novel Minimally Invasive Surgical Technique

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Metastasis accounts for nearly half of pathologic acetabular reconstructions.

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Increasing use of combined percutaneous ablation, cementoplasty, and osteosynthesis.

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Harrington or MAC classification may lead to overtreatment of acetabular lesions.

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Know indications for joint-sparing reconstruction; consider use in select patients.

Classically, patients with advanced lytic disease of the acetabulum secondary to metastatic bone disease are treated with complex arthroplasty reconstruction techniques. Advancements in percutaneous techniques have extended the indications for safer, minimally invasive procedures for patients with periacetabular metastasis without the need for complex hip replacement and the complications that follow it. The purpose of this report is to revisit the management of this group of patients and provide indications for an alternative minimally invasive joint-sparing technique. We describe a novel technique using a combination of percutaneous cryoablation, cementoplasty and two-screw fixation. With careful consideration of indications, excellent functional and oncologic outcomes one year after surgery is possible without the need for additional procedures.

Reinforced cementoplasty for pelvic tumour lesions and pelvic traumatic fractures: preliminary experience

OBJECTIVES

Pelvic bone pathological lesions and traumatic fractures are a considerable source of pain and disability. In this study, we sought to evaluate the effectiveness of reinforced cementoplasty (RC) in painful and unstable lesions involving the pelvic bone in terms of pain relief and functional recovery.

METHODS

All patients with neoplastic lesion or pelvic fracture for whom a pelvic bone RC was carried out between November 2013 and October 2017 were included in our study. All patients who failed the medical management, patients unsuitable for surgery, and patients with unstable osteolytic lesions were eligible to RC. Clinical outcome was evaluated with a 1-month and 6-month post-procedure follow-up. The primary endpoint was local pain relief measured by the visual analogue scale (VAS).

RESULTS

Twenty-two patients (18 females, 4 males; mean age of 65.4 ± 13.3 years [range 38-80]) presenting with painful and unstable pelvic lesions were treated by RC during the study period. Among the 22 patients, 8 patients presented with unstable pelvic fractures (3 patients with iliac crest fracture, 3 with sacral fractures, and the remaining 2 with peri-acetabular fractures). No procedure-related complications were recorded. All patients had significant pain relief and functional improvement at 1 month. One patient (4.5%) had suffered a secondary fracture due to local tumour progression.

CONCLUSIONS

Reinforced cementoplasty is an original minimally invasive technique that may help in providing pain relief and effective bone stability for neoplastic and traumatic lesions involving the pelvic bone.

KEY POINTS

• Reinforced cementoplasty is feasible in both traumatic fractures and tumoural bone lesions of the pelvis. • Reinforced cementoplasty for pelvic bone lesions provides pain relief and functional recovery. • Recurrence of pelvic bone fracture was observed in 4.5% of the cases in our series.

The role of surgery in the treatment of metastatic bone tumor

Surgery for bone metastasis has two primary goals-palliative care to relieve pain, instability and paralysis, and tumor resection for curing the disease. Oncologically en bloc resection, followed by a reconstruction of the bone defect is the treatment of choice in single bone metastasis from renal cell carcinoma or thyroid cancer. Bone metastases may occur in the extremities, pelvis, or spine, and different resection and reconstruction methods depend on the regional anatomy. For instance, multiple options are available for reconstruction of the pelvis, especially for the acetabulum, including anatomical reconstruction using custom-made implants or recycled autologous bone grafting when a long-term prognosis is expected. Recently, for the spine, total en bloc spondylectomy is extensively performed despite the initial limitations of surgical invasiveness, such as blood loss. Principally, palliative surgery aims to maintain lasting bony stability with minimal surgical invasiveness. Intramedullary nails and plate fixation are frequently used in the extremities but the postoperative failure rate is relatively high. Therefore, surgeons should consider the use of long intramedullary nails and long-type stems for endoprosthesis reconstruction along with cement fixation to reduce the failure rate. Although short-term complications, such as dislocation, have been observed with endoprosthesis reconstruction, it is stable in the long-term follow-up. Percutaneous bone cement injection into the spine and pelvis is also effective and less invasive.

A Tailored Approach for Appendicular Impending and Pathologic Fractures in Solid Cancer Metastases

Simple Summary

Patients with bone metastases often suffer with complications, such as bone fractures, which have a substantial negative impact on clinical outcomes. To optimize clinical results, a tailored approach should be defined for managing impending or pathologic fractures in each individual case. The ability to control systemic disease, the extent, location and nature of bone metastases, and the biology of the underlying tumor, are the main factors that will define the strategy to follow.

Abstract

Advances in medical and surgical treatment have played a major role in increasing the survival rates of cancer patients with metastatic bone disease. The clinical course of patients with bone metastases is often impaired by bone complications, such as bone fractures, which have a substantial negative impact on clinical outcomes. To optimize clinical results and prevent a detrimental impact on patients’ health, a tailored approach should be defined for any given patient. The optimal management of impending or pathologic fractures is unknown and relies on a multidisciplinary approach to tailor clinical decisions to each individual patient. The ability to control systemic disease, the extent, location and nature of bone metastases, and the biology of the underlying tumor, are the main factors that will define the strategy to follow. The present review covers the most recent data regarding impending and pathologic fractures in patients with bone metastases, and discusses the medical and surgical management of patients presenting with metastatic bone disease in different clinical settings.

Biomechanical restoration of metastatic cancer-induced peri-acetabular bone defects by ablation-osteoplasty-reinforcement-internal fixation technique (AORIF): To screw or not to screw?

BACKGROUND

Minimally invasive percutaneous polymethyl methacrylate cement augmentation procedures offer numerous clinical advantages for patients with periacetabular osteolytic metastatic bone defects in contrast to open reconstructive procedures that are associated with many complications. Several techniques, such as Ablation-Osteoplasty-Reinforcement-Internal Fixation (AORIF), cementoplasty alone, and screw fixation alone are currently used. There is no consensus on optimal skeletal reinforcement of diseased bones. The purpose of this study was to determine the most effective technique of percutaneous acetabular augmentation for joint preservation, with respect to resilience on cyclic loading and fracture pattern at maximal load to failure.

METHODS

Five cohorts of hemipelvis composite bones with uniform periacetabular defects and various types of reinforcement techniques were utilized to simulate osteolytic metastasis in the weight bearing dome of the acetabulum. Five groups of hemipelves underwent finite element analysis and biomechanical testing for load to failure, energy absorption to failure, stress relaxation on cyclic loading, and fracture locations.

RESULTS

The combination of screws and bone cement augmentation demonstrated significant higher energy absorption than the cement or screw only groups (p < 0.05), and better protection of acetabulum from displaced intraarticular fractures than the screws alone oror cement only groups (p < 0.05). Resilience to cyclic loading was higheest in the screw with cement fixation group than the screw only repair (p < 0.01), though not the cement fixation only group.

INTERPRETATION

These data support the hypothesis that cementoplasty combined with screw augmentation such as the AORIF technique provides the best protection of acetabulum from massive metastatic cancer-induced acetabular fractures compared to augmentation with screws or cement alone.

Pelvis weight-bearing ability after minimally invasive stabilizations for periacetabular lesion

Periacetabular metastatic lesions cause debilitating weight-bearing pain and pose a risk of pelvic pathologic fracture. Minimally invasive percutaneous stabilization is an alternative palliative therapy over extensive open reconstructive surgeries. This study aimed to investigate the biomechanical behaviors of three distinct techniques of percutaneous periacetabular stabilization. A total of 20 composite hemipelves custom-made to contain Harrington type III periacetabular lesion based on a patient's computed tomograpy scans were assigned to treatment groups of cementoplasty alone using polymethyl methacrylate (Cement), screw fixation alone using ischial and posterior-to-anterior screws (Screws), cement-augmented screws (Screws&Cement), and a control group (Untreated). All hemipelves were loaded in a mechanical test configuration mimicking a single-legged stance, and failure load, failure deformation, and construct stiffness were determined. In the experiments, Screws&Cement demonstrated the highest yield strength (4711 ± 362 N) and was 12% higher than Cement (4005 ± 304 N, p = 0.019), 125% higher than Screws (2097 ± 359 N, p < 0.0001), and 184% higher than Untreated (1658 ± 254 N, p < 0.0001). No significant difference in yield strength was found between Screws and Untreated. Screws&Cement also demonstrated the highest stiffness (1013 ± 92 N/mm), followed by Cement (893 ± 49 N/mm), and both groups were significantly stiffer than Screws (543 ± 114 N/mm, p < 0.0001) and Untreated (580 ± 91 N/mm, p < 0.0001 for Screws&Cement, and p = 0.0003 for Cement). This study demonstrated that a cement-augmented periacetabular reconstruction is an effective option for percutaneous treatment of Harrington III periacetabular metastatic lesion. The addition of pelvic screws over cementoplasty significantly improved the pelvis load-bearing strength. When large periacetabular lesions are present, augmented screw fixation appears to be the superior choice of treatment.

Percutaneous osteoplasty for painful bony lesions: a technical survey

Percutaneous osteoplasty (POP) is defined as the injection of bone cement into various painful bony lesions, refractory to conventional therapy, as an extended technique of percutaneous vertebroplasty (PVP). POP can be applied to benign osteochondral lesions and malignant metastatic lesions throughout the whole skeleton, whereas PVP is restricted to the vertebral body. Common spinal metastases occur in the thoracic (70%), lumbosacral (20%), and cervical (10%) vertebrae, in order of frequency. Extraspinal metastases into the ribs, scapulae, sternum, and humeral head commonly originate from lung and breast cancers; extraspinal metastases into the pelvis and femoral head come from prostate, urinary bladder, colon, and uterine cervical cancers. Pain is aggravated in the dependent (or weight bearing) position, or during movement (or respiration). The tenderness and imaging diagnosis should match. The supposed mechanism of pain relief in POP is the augmentation of damaged bones, thermal and chemical ablation of the nociceptive nerves, and local inhibition of tumor invasion. Adjacent (facet) joint injections may be needed prior to POP (PVP). The length and thickness of the applied needle should be chosen according to the targeted bone. Bone cement is also selected by its osteoconduction, osteoinduction, and osteogenesis. Needle route should be chosen as a shortcut to reach the target bony lesions, without damage to the nerves and vessels. POP is a promising minimally invasive procedure for immediate pain relief. This review provides a technical survey for POPs in painful bony lesions.

Current Overview of Treatment for Metastatic Bone Disease

The number of patients with bone metastasis increases as medical management and surgery improve the overall survival of patients with cancer. Bone metastasis can cause skeletal complications, including bone pain, pathological fractures, spinal cord or nerve root compression, and hypercalcemia. Before initiation of treatment for bone metastasis, it is important to exclude primary bone malignancy, which would require a completely different therapeutic approach. It is essential to select surgical methods considering the patient’s prognosis, quality of life, postoperative function, and risk of postoperative complications. Therefore, bone metastasis treatment requires a multidisciplinary team approach, including radiologists, oncologists, and orthopedic surgeons. Recently, many novel palliative treatment options have emerged for bone metastases, such as stereotactic body radiation therapy, radiopharmaceuticals, vertebroplasty, minimally invasive spine stabilization with percutaneous pedicle screws, acetabuloplasty, embolization, thermal ablation techniques, electrochemotherapy, and high-intensity focused ultrasound. These techniques are beneficial for patients who may not benefit from surgery or radiotherapy.

Percutaneous Cementoplasty for the Pelvis in Bone Metastasis: 12-Year Experience

Background

In advanced cancer patients, pelvic bone metastasis often causes pain and gait disturbance. The use of percutaneous bone cement [polymethylmethacrylate (PMMA)] injection for pain management and strengthening in pelvic bone metastasis has rarely been reported. To evaluate this method, we aimed to determine surgical outcomes and complications over a long-term follow-up period using a large patient group.

Patients and Methods

We retrospectively collected data from 178 patients who underwent percutaneous cementoplasty for pelvic metastatic lesions, 201 in total. Surgical outcomes evaluated included pain reduction and improvement of ambulation. Mortality within 1 month after procedure and pulmonary embolism caused by thrombus, fat, tumor emboli, or bone cement were investigated as surgical complications. For long-term survivors, pain relapse and mechanical failure were analyzed. The mean follow-up period was 12.6 months, and there were 159 fatalities at last follow-up.

Results

The mean regional pain numerical rating scale scores decreased from 6.1 preoperatively to 2.4 1 month after procedure (p < 0.01). Gait function was maintained, worsened, and uncheckable in 68%, 24%, and 8% of patients, respectively, 1 month after procedure. Of long-term survivors followed up for > 12 months (n = 53), there were no significant changes in serial plain radiographs, and regional pain aggravation was observed in 9%. Pulmonary cement embolism and bone cement implantation syndrome was observed in 11% and 10%, respectively. However, all patients with these complications were asymptomatic.

Conclusions

Percutaneous cement injection into the pelvis is a feasible and safe palliative surgical option for patients with advanced malignancy in terms of pain reduction and maintenance of ambulatory function under regional anesthesia.

Acetabular reconstruction in oncological surgery: A systematic review and meta-analysis of implant survivorship and patient outcomes

BACKGROUND

Reconstruction of the hip for peri-acetabular oncological disease remains a challenge. The objective of this study was to summarize the evidence and identify techniques utilized for primary and metastatic tumors of the acetabulum and hemipelvis.

METHODS

A systematic review of the published literature was carried out in accordance with PRISMA guidelines. MEDLINE, EMBASE and Cochrane databases identified relevant articles. Quality was assessed using the Newcastle-Ottawa Scale. The study was registered on PROSPERO.

RESULTS

53 papers were included, 16 were suitable for meta-analysis. 909 patients had primary and 1140 metastatic disease. 1094 patients underwent reconstruction with conventional total hip arthroplasty (with or without cup-cage or cement augmentation) or modifications of the Harrington procedure, collectively termed 'non-complex'. 928 patients underwent 'complex' reconstructions with either a modular hemipelvic, saddle, reverse snow-cone, custom-made or 3D-printed endoprosthesis. The most common complication was deep infection (11%) followed by dislocation (5%). Mean MSTS scores were 61.9% for 'non-complex' versus 63.2% for 'complex' reconstruction. Meta-analysis suggested increased mortality for primary (OR 3.14; 95% CI 1.15-8.54) and trends toward reduced mortality for metastatic disease (OR 0.93; 95% CI 0.26-3.29) following 'complex' versus 'non-complex' reconstruction. Reoperation rates were higher following 'complex' reconstruction for metastatic disease (OR 1.90; 95% CI 0.66-5.46) and similar for primary disease (OR 0.98; 95% CI 0.45-2.14).

CONCLUSIONS

Peri-acetabular tumors are associated with high rates of morbidity and mortality. Decisions regarding implant selection are multi-factorial with recent increase in the use of custom-made and 3D-printing technologies. Multiple factors contribute to the oncological outcome and patient function. Further research is required in order to guide optimal practice.

Clinical features and outcomes of metastatic bone tumors of the pelvis

OBJECTIVE

The number of patients with metastatic bone tumors of the pelvis (MBTP) has increased, and the risk of metastasis and recurrence in the pelvic bones is difficult to assess. Therefore, we investigated the clinical features and oncological outcomes of patients with MBTP.

METHODS

We analyzed the clinical features and oncological outcomes of MBTP in 72 patients (42 men, 30 women; mean age, 50.5 years) from 2008 to 2017. Recurrence in the pelvic bones and survival rates were analyzed with regard to patients' potential contributing factors.

RESULTS

Enneking region I was the area most commonly containing MBTP (47.3%). Low- and high-grade tumors were identified in 40 and 32 patients, respectively. The most common pathological type was adenomatous carcinoma (34.7%), and the most common primary lesion was lung cancer (20.8%). The 3-year overall recurrence rate within the pelvic bones was 34.7%, and the 5-year overall survival rate was 29.2%.

CONCLUSION

Patients with MBTP have a high risk of recurrence in the pelvic bones and poor survival after multimodal treatment. Pelvic recurrence might be affected by the metastatic involvement, tumor grade, surgical margins, and type of surgery, whereas the survival rate tends to be associated with the tumor grade.

Predicting Fracture Risk in Patients with Metastatic Bone Disease of the Femur: A Pictorial Review Using Three Different Techniques

One of the key roles of an orthopedic surgeon treating metastatic bone disease (MBD) is fracture risk prediction. Current widely used impending fracture risk tools such as Mirels scoring lack specificity. Two newer methods of fracture risk prediction, CT-based structural rigidity analysis (CTRA) and finite element analysis (FEA), have each been shown to be more accurate than Mirels. This case series illustrates comparative Mirels, CTRA, and FEA for 8 femurs in 7 subjects. These cases were selected from a much larger data set to portray examples of true positives, true negatives, false positives, and false negatives as defined by CTRA relative to the fracture outcome. Case illustrations demonstrate comparative Mirels and FEA. This series illustrates the use, efficacy, and limitations of these tools. As all current tools have limitations, further work is needed in refining and developing fracture risk prediction.

Combination therapy with percutaneous osteoplasty and transcatheter arterial chemoembolization for the treatment of pelvic bone metastases: preliminary report

PURPOSE

To compare the clinical efficacies of percutaneous osteoplasty (POP) and combination therapy with percutaneous osteoplasty and transcatheter arterial chemoembolization (POPTACE) for the treatment of pelvic bone metastases.

METHODS

A retrospective study of 100 patients with pelvic bone metastases who had been treated by POP (n = 50) and POPTACE (n = 50) was conducted in this work. The clinical efficacies of these two treatments were evaluated by comparing their pain and functional abilities and bone metastases ability at the pre- and post-operative time points.

RESULTS

POPTACE and POP treatments had no significant differences (P > 0.05) in VAS scores and KPS scores. Concerning tumor response, a partial response in 37 of 50 (74%) patients at 1 month for the POPTACE group and a partial response in 26 of 50 (52%) patients at 1 month for the POPC group were observed (P = 0.04). Although POPTACE and POP treatments had significant and similar ability in pain relief and functional recovery ability for the treatment of pelvic bone metastases, POPTACE treatment had a significantly better tumor response ability (partial response and stable response) compared with POP treatment.

CONCLUSION

Both POP and POPTACE were effective methods for the treatment of pelvic bone metastases. Moreover, these initial outcomes suggest POPTACE treatment may be better than POP treatment. POPTACE treatment has great value and is worth promoting vigorously in orthopedics clinics.

Image-guided Cryotherapy for Musculoskeletal Tumors

BACKGROUND

This article represents a review of the use of image-guided cryotherapy in the treatment of musculoskeletal tumor lesions. Cryotherapy is able to induce a lethal effect on cancer cells through direct and indirect mechanisms. In this manuscript, we combined our experience with that of other authors who have published on this topic in order to provide indications on when to use cryotherapy in musculoskeletal oncology.

DISCUSSION

Image-Guided percutaneous cryotherapy is a therapeutic method now widely accepted in the treatment of patients with musculoskeletal tumors. It can be used both for palliative treatments of metastatic bone lesions and for the curative treatment of benign bone tumors, such as osteoid osteoma or osteoblastoma. In the treatment of bone metastases, cryotherapy plays a major role in alleviating or resolving disease-related pain, but it has also been demonstrated that it can have a role in local disease control. In recent years, the use of cryotherapy has also expanded for the treatment of both benign and malignant soft tissue tumors.

CONCLUSION

Percutaneous cryotherapy can be considered a safe and effective technique in the treatment of benign and malignant musculoskeletal tumors. Cryotherapy can be considered the first option in benign tumor lesions, such as osteoid osteoma, and a valid alternative to radiofrequency ablation. In the treatment of painful bone metastases, it must be considered secondarily to other standard treatments (radiotherapy, bisphosphonate therapy, and chemotherapy) when they are no longer effective in controlling the disease or when they cannot be repeated (for example, radiotherapy).

Harrington rods for periacetabular pathological lesion: is it an option?

Advancement in cancer treatment has prolonged the survival of cancer patients; as a result, there are an increased number of patients with bone metastases and pathological fractures referred to orthopaedic surgeons for surgical intervention for a better quality of life. Metastasis around the hip joint can be painful and intervene with patients' daily activity, and reconstruction of the hip joint with periacetabular metastasis is complex and challenging especially longer cancer survivals might out-live their fixation. Several acetabular reconstruction techniques and implants have been described to overcome this problem; acetabular reconstruction and total hip arthroplasty still remains the standard surgical treatment, to relief pain and to improve function and quality of life. Harrington reconstruction of periacetabular metastatic disease combined with hip arthroplasty is one of the options that can address this clinical scenario safely; it is reproducible and cost-effective. In this review, we present case series of patients treated in our institution using Harrington rod technique for acetabular pathological lesions with good outcome.

Surgical treatment of peri-acetabular metastatic disease: Retrospective, multicentre study of 91 THA cases

INTRODUCTION

The occurrence of peri-acetabular metastasis (PAM) is a turning point in the progression of cancer because the disabling pain prevents the patient from walking or makes it difficult. Recent progress in controlling cancers that spread to the bone and controlling local bone destruction justify this national study. Since the data in France is incomplete or based on small studies, we analysed a multicentre retrospective cohort of patients with PAM who underwent total hip arthroplasty (THA) to evaluate 1) the clinical and radiological outcomes and 2) the factors impacting patient survival.

HYPOTHESIS

The clinical outcomes, complication rate and survivorship are comparable to that of recent published studies.

METHODS

Ninety-one patients (27 men, 64 women) with a mean age of 62.7±10.5 years (extremes 38 and 88) with PAM secondary to breast cancer [42 patients (46%)] or lung cancer [20 patients (22%)] underwent THA. The metastasis was the first sign of cancer in 33 cases (36%). Concurrent visceral metastases were present in 30 patients (33%), multiple peripheral bone metastasis in 48 patients (53%) and synchronous spine metastasis in 39 patients (43%). The most common construct was a cemented stem with metal reinforcement cage and cemented dual mobility cup [71 times (78%), while 85/91 had a dual mobility cup (93%)].

RESULTS

Elimination or reduction of pain was reported in 81 patients (91%). Overall walking ability was deemed normal or acceptable in 74 patients (83%). Six patients died (7%) before the end of the 3rd month. There were seven general complications (8%) including five thromboembolic events. There were 22 complications related to the surgical procedure in 20 patients (22%) that required surgical revision, including 10 surgical site infections (11%) and 3 dislocations (3%) (one concerning a dual mobility cup and 2 after single mobility cup). The median survivorship all causes combined was 19.5 months; it was 23.7 months for patients with breast cancer and 8.9 months for those with lung cancer.

CONCLUSION

Despite different endpoints being used, the clinical outcomes in our study are like those in other published studies, as were the incidence of surgery-related complications and the survivorship. The recommended surgical technique is the implantation of an acetabular reinforcement cage, curettage with cement filling of osteolytic areas, dual mobility cup and cemented stem followed by radiation therapy. The role of THA versus interventional radiology procedures must still be determined.

LEVEL OF EVIDENCE

IV, retrospective study without control group.

Spine and Non-spine Bone Metastases - Current Controversies and Future Direction

Bone is a common site of metastases in advanced cancers. The main symptom is pain, which increases morbidity and reduces quality of life. The treatment of bone metastases needs a multidisciplinary approach, with the main aim of relieving pain and improving quality of life. Apart from systemic anticancer therapy (hormonal therapy, chemotherapy or immunotherapy), there are several therapeutic options available to achieve palliation, including analgesics, surgery, local radiotherapy, bone-seeking radioisotopes and bone-modifying agents. Long-term use of non-steroidal analgesics and opiates is associated with significant side-effects, and tachyphylaxis. Radiotherapy is effective mainly in localised disease sites. Bone-targeting radionuclides are useful in patients with multiple metastatic lesions. Bone-modifying agents are beneficial in reducing skeletal-related events. This overview focuses on the role of surgery, including minimally invasive treatments, conventional radiotherapy in spinal and non-spinal bone metastases, bone-targeting radionuclides and bone-modifying agents in achieving palliation. We present the clinical data and their associated toxicity. Recent advances are also discussed.

Functional outcome of operative treatment for pelvic metastatic bone disease from primary thyroid cancer: A case series

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70 % of all malignant bone tumors are metastatic in origin.

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Functional outcome of MBD surgical management rarely described in literature.

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SF-36 and MSTS can be used to measure the functional outcome of MBD surgery.

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Surgery remains a good choice of therapy for MBD of pelvic.

Background

Metastatic bone disease (MBD) is the most common malignancy of bone. It is estimated that 70 % of all malignant bone tumors are due to metastasis. The functional outcome from pelvic MBD surgical management has been rarely described in the literature contrary to that of the long bones.

Method

We reported three patients that underwent pelvic resection surgery due to pelvic MBD. All of the primary tumors were thyroid cancer. We measure the functional outcome using SF-36 and MSTS (musculoskeletal tumor society) scores after a one-year follow-up.

Result

The SF-36 scoring result was that all of the patients had a remarkable improvement in terms of pain (77.5 %, 100 %, and 100 %). All of the patients also still had proper social functioning (75 %, 100 %, and 100 %) and good emotional well-being (72 %, 92 %, and 88 %). According to the MSTS, the second and third case had an excellent functional outcome; however the first case had poor functional outcome

Conclusion

Surgery remains the choice of therapy for pelvic MBD that results in alleviation of pain and quality of life improvement.

Percutaneous screw-reinforced cement osteoplasty for palliation of postremission pain in larger lytic sacro-acetabular iliac cavities

We present 2 cases of palliative percutaneous screw fixation for refractory pain from periacetabular residual cavities, after clinical remission, from osteolytic iliac masses involving the cortices of the sacroiliac joint (SIJ). Two patients-1 with a treated 8 cm breast metastasis and another with a treated 14 cm plasmacytoma-were selected for osseous stabilization based on imaging criteria and physical signs of iliac deformability and SIJ dysfunction. Neither lesion exhibited active malignancy following systemic therapy or discrete fracture. Following computed tomography-guided screw fixation across the mass and SIJ, with surrounding cement osteoplasty, to reduce mechanical stress on abnormal bone, both patients reported pain resolution beyond 1-year. This technique may be a suitable palliation even for large treated pelvic metastastic cavities and in the absence of fracture.

Principles of Management of Extremity Skeletal Metastasis

Understanding the epidemiology of extremity skeletal metastasis and the factors deciding the treatment decision-making are essential in developing a diagnostic and treatment strategy. This leads to optimum care and reduces disease-related burden. With the evolution of medical, radiation therapy, and surgical methods, cancer care has improved the quality of life for patients with improved survival and functional status in patients with skeletal metastasis. Based on the currently available literature, we have described a step-wise evaluation and management strategy of metastatic extremity bone disease. The present review article addresses various aspects and related controversies related to evaluation, staging, and treatment options in the management of extremity bone metastasis. This article also highlights the role of multidisciplinary involvement in management of extremity skeletal metastasis.

Multimodal Treatment of Bone Metastasis-A Surgical Perspective

Over the past decades there has been an increase in the incidence of cancer worldwide. With the advancement in treatment, patient survival has improved in tandem with the increasing incidence. This, together with the availability of advanced modern diagnostic modalities, has resulted in more cases of metastatic bone disease being identified. Bone metastasis is an ongoing problem and has significant morbidity implications for patients affected. Multimodal treatment strategies are required in dealing with metastatic bone disease, which include both surgical and non-surgical treatment options. In the multidisciplinary team, orthopedic surgeons play an important role in improving the quality of life of cancer patients. Surgical intervention in this setting is aimed at pain relief, restoration of function and improvement in functional independence. In selected cases with resectable solitary metastasis, surgical treatment may be curative. With the advancement of surgical technique and improvement in implant design and manufacture, a vast array of surgical options are available in the modern orthopedic arena. In the majority of cases, limb salvage procedures have become the standard of care in the treatment of metastatic bone disease. Non-surgical adjuvant treatment also contributes significantly to the improvement of cancer patient care. A multidisciplinary approach in this setting is of paramount importance.

Magnetic Resonance-Guided Focused Ultrasound Versus Conventional Radiation Therapy for Painful Bone Metastasis: A Matched-Pair Study

BACKGROUND

Magnetic resonance-guided focused ultrasound (MRgFUS) is an alternative local therapy for patients with painful bone metastasis for whom standard conventional radiation therapy (RT) has failed. However, the therapeutic effects of MRgFUS as a first-line treatment for bone metastasis remain uncertain.

METHODS

A matched-pair study was conducted to compare the therapeutic effects of MRgFUS with those of conventional RT as a first-line treatment for patients with painful bone metastasis. The MRgFUS and RT-treated groups were matched 1:2 by age, sex, primary cancer, pretreatment pain score, and treated site.

RESULTS

According to the criteria for patient eligibility and matching, 21 and 42 patients (total, 63 patients) with bone metastasis treated with MRgFUS and conventional RT, respectively, were enrolled for analyses. The median ages of the MRgFUS and RT-treated patients were 59 and 61 years, respectively. Among the enrolled patients, 52% were male and 48% were female. The results showed that both MRgFUS and RT were effective. However, MRgFUS was more efficient than RT in terms of the time course of pain palliation as it yielded a significantly higher response rate at 1 week after treatment (71% versus 26%, p = 0.0009).

CONCLUSIONS

MRgFUS provides a similar overall treatment response rate but faster pain relief compared with conventional RT and has the potential to serve as the first-line treatment for painful bone metastasis in selected patients.

LEVEL OF EVIDENCE

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

Oligometastatic colorectal cancer: is single-site bony colorectal metastasis a treatable condition?

INTRODUCTION

A potentially resectable bony metastasis in the context of oligometastatic colorectal cancer is uncommon. Bony metastases are usually considered a late event with poor prognosis and generally associated with liver and/or lung metastases.

INDEX CASE

A previously healthy 33-year-old gentleman, with no family history of colorectal cancer, presented with rectal bleeding and at colonoscopy had a biopsy-proven adenocarcinoma of the rectum, 7 cm from the anal verge. Imaging also showed an isolated bone metastasis in the left ischial tuberosity. Following recovery from an anterior resection and a segment 5 metastasectomy, he underwent resection of the bony metastasis with a left type 3 internal hemipelvectomy. Three years from the bony resection, there is no evidence of recurrence on imaging.

DISCUSSION

Osseous metastases are usually treated with palliative intent with bisphosphonates or external radiation, with surgical fixation of pathological fractures in some cases. Median survival after diagnosis of bone metastases is less than 10 months. Surgery is perhaps the only way of potentially achieving cure in patients with single-site bony metastases from colorectal cancer. Reports of such surgery in the literature are however very scant.

CONCLUSION

Our case is unusual and ongoing follow up is required. However, current disease-free status at conventional and functional imaging is encouraging. A multidisciplinary and indeed multicentre approach may be needed, and oligometastatic disease, even to a bone, may be amenable to curative surgical intervention in highly selected cases.

Features and Role of Minimally Invasive Palliative Procedures for Pain Management in Malignant Pelvic Diseases: A Review

Pain is a common and debilitating symptom in pelvic cancer diseases. Failure in controlling this pain through pharmacological approaches calls for employing multimodal management and invasive techniques. Various strategies are commonly used for this purpose, including palliative radiotherapy, epidural medications and intrathecal administration of analgesic and local anesthetic drugs with pumps, and neural or plexus blockade. This review focuses on the features of minimally invasive palliative procedures (MIPPs), such as radiofrequency ablation, laser-induced thermotherapy, cryoablation, irreversible electroporation, electrochemotherapy, microwave ablation, and cementoplasty as well as their role in palliation of cancer pelvic pain. Despite the evidence of effectiveness and safety of these interventions, there are still many barriers to accessing MIPPs, including the availability of trained staff, the lack of precise criteria of indication, and the high costs.

Decision Making: Osteoplasty, Ablation, or Combined Therapy for Spinal Metastases

Metastatic disease involving the spine and pelvis is common, often resulting in significant pain and disability. Several percutaneous interventions have been described, including osteoplasty, ablation, and screw fixation, that when used alone or in combination can significantly reduce pain and disability from metastatic bone disease. Although it is possible to make a significant impact in patient care with basic principles and techniques, certain advanced techniques can extend the application of percutaneous interventions while minimizing morbidity.

Treatment of metastatic lesions localized in the acetabulum

BACKGROUND

Metastatic lesions localized in the periacetabular area cause troublesome pain and reduced mobility of the patients. Radiotherapy effectively decreases pain, yet it does not restore the ability to load the joint. Surgical treatment involving resection of metastatic lesions and joint reconstruction using bone grafts is burdened with a high rate of complications. Modular tumor prostheses are being increasingly used. In some cases, it is possible to strengthen the acetabular roof with bone cement using vertebroplasty kits. The aim of the study was to demonstrate various methods of treatment of metastatic lesions localized in the periacetabular area together with the analysis of their results and effectiveness.

METHODS

Between 2010 and 2015, 27 patients with cancer metastases to the acetabulum were treated at our department. Qualification for surgical treatment was multifaceted with numerous aspects being considered. They included patients' general condition, type of neoplasm, clinical stage, and prognosis. CT and MRI scans of the pelvis were performed in each case. Before the surgery and 3 months following the surgery, visual analogue scale (VAS) pain intensity, Karnofsky functional status, and motor ability according to the Harris scale were evaluated. Bone cement (PMMA)-augmentation was performed in 21 patients, of whom nine had cement injected precutaneously and 12 at proximal femur resection alloplasty. Hemipelvectomy Type II combined with implantation of LUMiC resection prosthesis of the acetabulum were performed in six cases.

RESULTS

The quality of life improved in all the patients. After percutaneous cement injection, the mean pain intensity VAS score was 2.7, and the mean Karnofsky functional status score was 71.8. The mean postoperative Harris hip score (HHS) was 94 points. The patients who had undergone resection alloplasty on the proximal femur combined with periacetabular cement injection were walking using one crutch. In this group of patients, the mean postoperative pain intensity, functional status, and gait efficiency scores were 4.5, 65.7, and 82 points, respectively. The mean pain intensity VAS score in patients who had LUMiC prostheses implanted was 3.4. Their mean functional status score was 65 and the gait efficiency score 71 points. All the patients were able to walk on crutches.

CONCLUSIONS

Strengthening of the acetabular roof with bone cement in a specific group of patients is an adequate method of treatment which decreases pain and allows for loading the affected limb while walking. Internal hemipelvectomy combined with LUMiC prosthesis implantation makes it possible for the patients to walk using crutches and significantly reduces pain.

Differential osteogenic potential of human adipose-derived stem cells co-cultured with human osteoblasts on polymeric microfiber scaffolds

The osteogenic potential of human adipose-derived stem cells (HADSCs) co-cultured with human osteoblasts (HOBs) using selected HADSCs/HOBs ratios of 1:1, 2:1, and 1:2, respectively, is evaluated. The HADSCs/HOBs were seeded on electrospun three-dimensional poly[(R)-3-hydroxybutyric acid] (PHB) blended with bovine-derived hydroxyapatite (BHA). Monocultures of HADSCs and HOBs were used as control groups. The effects of PHB-BHA scaffold on cell proliferation and cell morphology were assessed by AlamarBlue assay and field emission scanning electron microscopy. Cell differentiation, cell mineralization, and osteogenic-related gene expression of co-culture HADSCs/HOBs were examined by alkaline phosphatase (ALP) assay, alizarin Red S assay, and quantitative real time PCR, respectively. The results showed that co-culture of HADSCs/HOBs, 1:1 grown into PHB-BHA promoted better cell adhesion, displayed a significant higher cell proliferation, higher production of ALP, extracellular mineralization and osteogenic-related gene expression of run-related transcription factor, bone sialoprotein, osteopontin, and osteocalcin compared to other co-culture groups. This result also suggests that the use of electrospun PHB-BHA in a co-culture HADSCs/HOBs system may serve as promising approach to facilitate osteogenic differentiation activity of HADSCs through direct cell-to-cell contact with HOBs.