Hemipelvectomy- only a salvage therapy?

Changes in walking function and neural control following pelvic cancer surgery with reconstruction

Introduction: Surgical planning and custom prosthesis design for pelvic cancer patients are challenging due to the unique clinical characteristics of each patient and the significant amount of pelvic bone and hip musculature often removed. Limb-sparing internal hemipelvectomy surgery with custom prosthesis reconstruction has become a viable option for this patient population. However, little is known about how post-surgery walking function and neural control change from pre-surgery conditions. Methods: This case study combined comprehensive walking data (video motion capture, ground reaction, and electromyography) with personalized neuromusculoskeletal computer models to provide a thorough assessment of pre- to post-surgery changes in walking function (ground reactions, joint motions, and joint moments) and neural control (muscle synergies) for a single pelvic sarcoma patient who received internal hemipelvectomy surgery with custom prosthesis reconstruction. Pre- and post-surgery walking function and neural control were quantified using pre- and post-surgery neuromusculoskeletal models, respectively, whose pelvic anatomy, joint functional axes, muscle-tendon properties, and muscle synergy controls were personalized using the participant's pre-and post-surgery walking and imaging data. For the post-surgery model, virtual surgery was performed to emulate the implemented surgical decisions, including removal of hip muscles and implantation of a custom prosthesis with total hip replacement. Results: The participant's post-surgery walking function was marked by a slower self-selected walking speed coupled with several compensatory mechanisms necessitated by lost or impaired hip muscle function, while the participant's post-surgery neural control demonstrated a dramatic change in coordination strategy (as evidenced by modified time-invariant synergy vectors) with little change in recruitment timing (as evidenced by conserved time-varying synergy activations). Furthermore, the participant's post-surgery muscle activations were fitted accurately using his pre-surgery synergy activations but fitted poorly using his pre-surgery synergy vectors. Discussion: These results provide valuable information about which aspects of post-surgery walking function could potentially be improved through modifications to surgical decisions, custom prosthesis design, or rehabilitation protocol, as well as how computational simulations could be formulated to predict post-surgery walking function reliably given a patient's pre-surgery walking data and the planned surgical decisions and custom prosthesis design.

A computational method for estimating trunk muscle activations during gait using lower extremity muscle synergies

One of the surgical treatments for pelvic sarcoma is the restoration of hip function with a custom pelvic prosthesis after cancerous tumor removal. The orthopedic oncologist and orthopedic implant company must make numerous often subjective decisions regarding the design of the pelvic surgery and custom pelvic prosthesis. Using personalized musculoskeletal computer models to predict post-surgery walking function and custom pelvic prosthesis loading is an emerging method for making surgical and custom prosthesis design decisions in a more objective manner. Such predictions would necessitate the estimation of forces generated by muscles spanning the lower trunk and all joints of the lower extremities. However, estimating trunk and leg muscle forces simultaneously during walking based on electromyography (EMG) data remains challenging due to the limited number of EMG channels typically used for measurement of leg muscle activity. This study developed a computational method for estimating unmeasured trunk muscle activations during walking using lower extremity muscle synergies. To facilitate the calibration of an EMG-driven model and the estimation of leg muscle activations, EMG data were collected from each leg. Using non-negative matrix factorization, muscle synergies were extracted from activations of leg muscles. On the basis of previous studies, it was hypothesized that the time-varying synergy activations were shared between the trunk and leg muscles. The synergy weights required to reconstruct the trunk muscle activations were determined through optimization. The accuracy of the synergy-based method was dependent on the number of synergies and optimization formulation. With seven synergies and an increased level of activation minimization, the estimated activations of the erector spinae were strongly correlated with their measured activity. This study created a custom full-body model by combining two existing musculoskeletal models. The model was further modified and heavily personalized to represent various aspects of the pelvic sarcoma patient, all of which contributed to the estimation of trunk muscle activations. This proposed method can facilitate the prediction of post-surgery walking function and pelvic prosthesis loading, as well as provide objective evaluations for surgical and prosthesis design decisions.

Comparative study of pelvic sarcoma patients undergoing internal and external hemipelvectomy: A meta-analysis study

Introduction

Malignant and giant pelvic tumors are complex and rare, and hemipelvectomies are complex procedures performed for this malignant lesion. Only a few studies had been conducted on the survival and recurrence of pelvic sarcomas patients undergoing internal or external hemipelvectomy. In the present study, we compared internal with external hemipelvectomy in pelvic sarcomas on clinical outcomes by a meta-analysis.

Methods

The survival and recurrence rates of pelvic sarcomas patients were collected from research reports from CNKI, MEDLINE, EMBASE, the Cochrane Database, and Google Scholar until April 2022. The quality of included articles was evaluated by two independent reviewers. Differences between patients undergoing internal and external hemipelvectomy were analyzed based on postoperative survival and recurrence rates.

Results

Five articles were included according to selection criteria. There were 183 patients in total from these studies. Our results showed that there was no significant difference between limb salvage surgery and amputation according to survival; however, patients with internal hemipelvectomy had a lower recurrence rate.

Conclusions

Internal hemipelvectomy results in a lower recurrence rate and similar survival rate, while not increasing the risk of metastasis and complications. This study provided more pieces of evidence to support internal hemipelvectomy as a favorable treatment of pelvic sarcomas.

Diagnosis and Management of Traumatic Hemipelvectomy

Traumatic hemipelvectomy (THP) is a catastrophic injury associated with high-energy trauma and high mortality. THP has been defined as a complete dislocation of the hemipelvis, often with disruption through the symphysis pubis and sacroiliac joint with concurrent traumatic rupture of the iliac vessels. Despite recent advances in prehospital resuscitative techniques, the true incidence of THP is difficult to ascertain because many patients die before hospital arrival. The leading causes of death associated with THP include blood loss, infection, and multiple system organ failure. Recognition and immediate intervention for these injuries is imperative for survival. The initial assessment includes a thorough physical examination assessing for signs of arterial damage and other associated injuries. Hemorrhage control and vigorous resuscitation should be prioritized to combat impending exsanguination. Emergent amputation has been found to be a lifesaving operation in these patients. The basis of this approach is rooted in achieving complete hemostasis while reducing complication rates. Understanding the nature of these massive pelvic injuries, the role of early amputation, and the importance of subspecialty communication can improve survivability and optimize patient outcomes.

"Prevalence of chronic pain following resection of pelvic bone tumours: A single centre prospective observational survey"

Background

Hemipelvectomy is a major surgery most often performed for pelvic malignancy. These complex surgeries often involve dissection around major neurovascular bundle and resection of tumour being bone along with involved tissues. This may result in short and long term morbidities. There is very little literature about incidence of chronic pain after pelvic resections. We conducted a prospective study at a tertiary cancer hospital to assess the prevalence of chronic pain post hemipelvectomy.

Method

This is a single centre prospective observational study conducted over 30 months. Pain scores were recorded using Brief pain inventory (BPI) and pain detect questionnaire. The quality of life was assessed using musculoskeletal tumour society (MSTS) score. Intra-operative details like extent of surgical resection, nerves spared, details of intra-operative and post-operative analgesia were retrieved from the patient files. Data were analysed using SPSS 21 version.

Results

Neuropathic pain post hemipelvectomy was uncommon. The prevalence of mild to moderate somatic pain was around 30%. Functional limitation was minimal as assessed by BPI and MSTS score. A high incidence of numbness was seen to persist in and around the area of surgical incision (50%).

Conclusion

This is first study to report the incidence of chronic pain post hemipelvectomy done for pelvic tumour resections. Despite the extensive nature of resection involved, there is a low prevalence of neuropathic pain in this population. However, incidence of persistent somatic pain is high and there is a need for further studies for evaluating the causality.

Pain and Analgesia in Children with Cancer after Hemipelvectomy: A Retrospective Analysis

A paucity of data exists centering on the pain experience of children following hemipelvectomy performed for primary bone and soft tissue sarcomas. In this study, we aimed to describe the incidence, severity, and evolution of perioperative pain and function in pediatric oncology patients undergoing hemipelvectomy, and, additionally, we sought to detail the analgesic regimens used for these patients perioperatively. A retrospective chart review was conducted, studying cancer patients, aged 21 years and under, who underwent hemipelvectomy at MD Anderson Cancer Center (MDACC) from 2018 to 2021. Primary outcomes included the evolution of pain throughout the perioperative course, as well as the route, type, dose, and duration of analgesic regimens. Eight patients were included in the analysis. The mean age at operation was 13 ± 2.93 years. All patients received opioids and acetaminophen. The mean pain scores were highest on post-operative day (POD)0, POD5, and POD 30. The mean opioid use was highest on POD5. A total of 75% of patients were noted to be ambulating after hemipelvectomy. The mean time to ambulation was 5.33 ± 2.94 days. The combination of acetaminophen with opioids, as well as adjunctive regional analgesia, non-steroidal anti-inflammatory drugs, gabapentin, and/or ketamine in select patients, appeared to be an effective analgesic regimen, and functional outcomes were excellent in 75% of patients.

Cranial internal hemipelvectomy (iliectomy) with limb sparing for a dog with ilial chondrosarcoma: A case report

Cranial internal hemipelvectomy can be successful for excision of ilial CSA with minimal complications. Iliectomy with adjuvant radiation therapy was well tolerated in a dog with grade II ilial CSA. The dog survived 1,271 days postoperatively and supposedly succumbed to a disease process unrelated to the CSA.

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

INTRODUCTION

Pelvic ring reconstruction after internal hemipelvectomy is an extremely challenging surgical procedure, and mandatory reconstruction is to provide a durable and pain-free functional outcome, especially for young, active patients. One of the most widely employed techniques is reconstruction with a double-barreled fibular free flap (DBF). The aim of our work was an in-depth analysis of the outcome of pelvic ring reconstruction performed using the above-mentioned method, in particular looking for a correlation between the fixation technique and either ambulation status or complications.

MATERIALS AND METHODS

A systematic review was performed in November 2020 using PubMed and MedLine Ovid databases according to the PRISMA guidelines and the results were statistically analyzed.

RESULTS

Studies were published between 1994 and 2015. A DBF was used in each case, with a total of 30 patients. Reconstruction was performed with screws in 13 cases, Cotrel-Dubousset rod fixation in 6, screws and plate in 5, screws with external fixation in 4, and ISOLA in 2. Follow-up time ranged from 3 to 131 months. Functional outcome was excellent in 4 patients and good in 26 patients. Statistical analysis showed no statistical evidence of existing correlation between fixation technique and complications (p = .873), while statistical correlation between age and fixation technique was found (p < .001).

CONCLUSION

Reconstruction of pelvic ring with DBF provides an overall good functional outcome. Our data indicate that there is no statistical evidence of existing correlation between the fixation technique and either complications or ambulation status.

Internal Hemipelvectomy and Pelvic Reconstruction With Non-Vascularized Fibular Graft for Chondrosarcoma Ilium

Chondrosarcoma is the third most common primary malignant bone tumor. The pelvis is the most common site with iliac bone being frequently involved. Hindquarter amputation was the standard treatment for pelvic osteosarcoma for years. Resection of tumors with wide margins gained popularity with advances in the medical field. The only resection without reconstruction of the pelvis has its own demerits which paved way for methods of reconstruction. One of these is pelvic reconstruction with non-vascularised fibular graft among many other methods, which is simple, cost-effective, and has a good functional outcome. Here, we are reporting a case of exophytic chondrosarcoma of intermediate grade in ilium in a 19-year-old male for whom internal hemipelvectomy (Enneking and Dunham type 1) and pelvic reconstruction with non-vascularised fibular graft was done with the excellent functional and radiological outcome, with a two-year follow-up.

Predictors and Survival of Patients with Osteosarcoma After Limb Salvage versus Amputation: A Population-Based Analysis with Propensity Score Matching

BACKGROUND

Conflicting findings have been reported concerning the survival of patients treated with limb salvage and amputation for osteosarcoma. This study aimed to identify predictors associated with surgery types and survival difference.

METHODS

Patients with osteosarcoma were selected from the Surveillance Epidemiology and End Results database (1975-2016). Multivariable logistic regression analysis was conducted, and a nomogram was further established. Propensity score matching (PSM)-adjusted Kaplan-Meier curves, log-rank tests, Cox proportional hazards regression analysis were performed to compare overall survival (OS) and cancer-specific survival (CSS).

RESULTS

Among 3363 patients with osteosarcoma, 2447 and 916 underwent limb salvage and amputation. Predictors associated with amputation in the nomogram included age, gender, primary tumor site, tumor grade, tumor stage, tumor size and radiotherapy. Totally 900 pairs of patients treated with limb salvage and amputation were matched after PSM. Limb salvage was significantly associated with improved OS (HR, 0.773; 95% CI, 0.670-0.892; p < 0.001) and CSS (HR, 0.795; 95% CI, 0.681-0.927; p = 0.003) in PSM-adjusted cohort after adjusting for related variables. The significant treatment effect of limb salvage was consistent within most subgroups. Among patients treated with surgery for osteosarcoma, age between 41 and 60, age ≥ 61, pelvis as the primary site, high tumor grade (III/IV), regional and distant tumor stage, tumor size ≥ 92 mm and radiotherapy were independent prognostic factors in PSM cohort.

CONCLUSIONS

Limb salvage exhibits significant benefit on OS and CSS compared with amputation for osteosarcoma. Predicators and survival differences should be given full consideration for the treatment of osteosarcoma.

Iliac Telangiectatic Osteosarcoma - A Rare Presentation and Diagnostic Pitfall: A Case Report

Telangiectatic osteosarcoma is a rare variant of osteosarcoma and can be easily misdiagnosed as aneurysmal bone cyst. We report an atypical case of iliac telangiectatic osteosarcoma in a young healthy female, who presents with painful slow growing expansile lytic septate lesion in the left hemipelvis, which is initially treated as aneurysmal bone cyst. The diagnosis of aneurysmal bone cyst is made after histopathological examination of core needle biopsy. Her condition became unstable and massive bleeding is noted at the lesion site after sclerosant injection. She undergoes emergency hemipelvectomy and eventually the biopsy turns up to be telangiectatic osteosarcoma. Our case highlights that core needle biopsy is not useful in making diagnosis for iliac telangiectatic carcinoma. Hence, an open biopsy should be carried out in our case. This case also emphasises on careful evaluation for malignancy which is mandatory because bleeding from pelvis after an unsuitable treatment can be grave, to the extent that major amputation hemipelvectomy is an option. Even though telangiectatic osteosarcoma has the same prognosis and treatment with conventional osteosarcoma, the outcome of delayed treatment for telangiectatic osteosarcoma is not good due to the dilemma in establishing an early correct diagnosis.

Surgical and oncological outcomes after hindquarter amputation for pelvic sarcoma

Aims

Survival rates and local control after resection of a sarcoma of the pelvis compare poorly to those of the limbs and have a high incidence of complications. The outcome for patients who need a hindquarter amputation (HQA) to treat a pelvic sarcoma is poor. Our aim was to evaluate the patient, tumour, and reconstructive factors that affect the survival of the patients who undergo HQA for primary or recurrent pelvic sarcoma.

Methods

We carried out a retrospective review of all sarcoma patients who had undergone a HQA in a supraregional sarcoma unit between 1996 and 2018. Outcomes included oncological, surgical, and survival characteristics.

Results

A total of 136 patients, with a mean age of 51 (12 to 83) underwent HQA, 91 for a bone sarcoma and 45 for a soft tissue sarcoma. The overall survival (OS) after primary HQA for a bone sarcoma was 90.7 months (95% confidence interval (CI) 64.1 to 117.2). In patients undergoing a secondary salvage HQA it was 90.3 months (95% CI 58.1 to 122.5) (p = 0.727). For those treated for a soft tissue sarcoma (STS), the mean OS was 59.3 months (95% CI 31.1 to 88.6) for patients with a primary HQA, and 12.5 months (95% CI 9.4 to 15.5) for those undergoing a secondary salvage HQA (p = 0.038). On multivariate analysis, high histological grade (hazard ratio (HR) 2.033, 95% CI 1.127 to 3.676; p = 0.018) and a diagnosis of STS (HR 1.653, 95% CI 1.027 to 2.660; p = 0.039) were associated with a poor prognosis. The 30-day mortality for patients with curative intent was 0.8% (1/128). For those in whom surgery was carried out with palliative intent it was 33.3% (2/6) (p = 0.001). In total, 53.7% (n = 73) of patients had at least one complication with 23.5% (n = 32) requiring at least one further operation. Direct closure was inferior to flap reconstruction in terms of complete primary wound healing (60.0% (3/5) vs 82.0% (82/100); p = 0.023).

Conclusion

In carefully selected patients HQA is associated with satisfactory overall survival, with a low risk of perioperative mortality, but considerable morbidity. However, caution must be exercised when considering the procedure for palliation due to the high incidence of early postoperative mortality. Cite this article: Bone Joint J 2020;102-B(6):788–794.

Extra-articular resection is a limb-salvage option for sarcoma involving the hip joint

INTRODUCTION

With the development of surgical techniques and improvements in hemi-pelvic prosthesis systems, extra-articular resection can be performed as a limb-salvage procedure in selected patients whose hip joint is invaded by a sarcoma. The aim of this study was to describe the indications for and the technical details, post-operative complications, and oncologic and functional outcomes of this procedure.

METHODS

Eighteen patients with Enneking IIB or IB sarcoma who underwent extra-articular resection of the hip joint were enrolled. A modular pelvic endoprosthesis combined with a femoral endoprosthesis was used to reconstruct the bone and joint defect. Pathological diagnoses included osteosarcoma (7 patients), chondrosarcoma (7), undifferentiated high-grade pleomorphic sarcoma (3), and malignant peripheral nerve-sheath tumour (1).

RESULTS

Wide, marginal and intralesional surgical margin was achieved in 13, four and one patients, respectively. There was one peri-operative death and the other 17 patients were followed up for 35.0 months (range, 10-75 months). Three patients had early-stage dislocations. One had a traumatic dislocation three years later. Two patients had wound complications. The average MSTS 93 score was 63.5% ± 10.8%. Four patients had local recurrence. The estimated three-year disease-free survival and overall survival for the 18 patients were both 50.0%.

CONCLUSION

Although technically demanding, extra-articular resection of hip is a limb-salvage procedure that is worth considering for carefully selected patients.

Outcomes of internal hemipelvectomy for pelvic tumors: a developing country's prospective

Introduction

Previously, external hemipelvectomy was the mainstay of treatment for pelvic tumors. However, with technological advancements, limb salvage procedures such as internal hemipelvectomy have emerged as a viable alternative. However, there is limited literature available on long-term outcomes and complications of internal hemipelvectomy, especially from developing countries. Therefore, the objective of this study was to share our experience of internal hemipelvectomy at a tertiary care center in a developing country.

Materials and methods

A retrospective review was conducted in which all 24 patients undergoing internal hemipelvectomy from January 1, 2005 to December 31, 2015 at our institution were included. Medical record files were reviewed for intraoperative and early and late postoperative complications, and functional outcomes were assessed by contacting each patient on telephone.

Results

Ewing sarcoma was found to be the most common diagnosis, followed by osteosarcoma as the second most common. The mean follow-up period was 18.7±13.9 months. Intraoperatively there were 4 cases of iatrogenic neurovascular injury and 2 cases each of urinary tract injury and dural tear. Four patients developed early wound infections, 7 developed late wound infections, and 2 developed flap necrosis. Three patients developed recurrence, whereas 7 patients developed metastasis postoperatively. The mean survival was calculated to be 28 months and the mean Musculoskeletal Tumor Society score was 19.3±5.2.

Conclusions

Outcomes and prevalence of complications shown in this study are comparable to those in the international literature, which suggests that hemipelvectomy is a viable option in developing countries also. However, more such studies are warranted to validate the findings and to identify the challenges and morbidities associated with hemipelvectomy in Asian and developing countries.

Oncologic Outcome and Quality of Life After Hindquarter Amputation for Sarcoma: Is it Worth it?

BACKGROUND AND OBJECTIVE

Hindquarter amputations for bone or soft tissue sarcoma cause a high degree of disability. The goal of this study was to analyze oncologic outcome and quality of life after resection in order to better select patients who are more likely to benefit from this operation.

METHODS

Patients treated with a hindquarter amputation between 1989 and 2015 for a bone or soft tissue sarcoma were selected from our database. Clinical and histopathological features were analyzed for their prognostic value using Kaplan-Meier and Cox proportional hazard analysis. In addition, performance status, ambulatory status, and pain were assessed from the hospital charts for patients surviving longer than 1 year after surgery.

RESULTS

Overall, 78 patients underwent a hindquarter amputation for sarcoma. The median hospital stay was 24 days and 49% of patients had wound complications. In-hospital mortality was 6%. Overall survival for patients with metastases at presentation was significantly worse than patients with localized disease only (p = 0.001, 5-year survival 41 vs. 0%). For patients treated for localized disease, the combination of age >65 years and tumor size ≥15 cm was significantly correlated with worse metastasis-free survival (p = 0.003) and overall survival (p = 0.01). In particular, patients younger than 65 years of age who survived more than 1 year had an acceptable performance status, with reasonable pain levels and mobility.

CONCLUSION

Younger patients are more likely to benefit from hindquarter ampuations in terms of survival and functionality; however, for older patients with large tumors, a hindquarter amputation might not be beneficial.

Survival rate and perioperative data of patients who have undergone hemipelvectomy: a retrospective case series

Background

Hemipelvectomy is a major orthopedic surgical procedure indicated in specific situations. Although many studies discuss surgical techniques for hemipelvectomy, few studies have presented survival data, especially in underdeveloped countries. Additionally, there is limited information on anesthesia for orthopedic oncologic surgeries. The primary aim of this study was to determine the survival rate after hemipelvectomy, and the secondary aims were to evaluate anesthesia and perioperative care associated with hemipelvectomy and determine the influence of the surgical technique (external hemipelvectomy [amputation] or internal hemipelvectomy [limb sparing surgery]) on anesthesia and perioperative care in Brazil.

Methods

This retrospective case series collected data from 35 adult patients who underwent hemipelvectomy between 2000 and 2013. Survival rates after surgery were determined, and group comparisons were performed using the Kaplan–Meier method and the log-rank test. Mantel–Cox test and multiple linear regression analysis with stepwise forward selection were performed for univariate and multivariate analyses, respectively.

Results

Mean survival time was 32.8 ± 4.6 months and 5-year survival rate was 27 %. Of the 35 patients, 23 patients (65.7 %) underwent external hemipelvectomy and 12 patients (34.3 %) underwent internal hemipelvectomy. The survival rate was significantly higher in patients with bone tumors than in those with soft tissue sarcomas (P = 0.024). The 5-year cumulative probability of survival was significantly lower in patients who underwent external hemipelvectomy than in those who underwent internal hemipelvectomy (P = 0.043). In the univariate and multivariate analyses, only advanced disease stage (3 and 4) was identified as a significant independent predictor of reduced survival (P = 0.0003). Balanced general anesthesia combined with epidural block was the most frequent anesthesia technique. Median intraoperative crystalloid volume and red blood cell transfusions were 3500 mL and 2 units, respectively.

Conclusions

Overall mean survival time after hemipelvectomy was 32.8 months. Advanced disease stage might be independently associated with reduced survival. Smaller amounts of fluids and transfusions were administered and time to discharge was shorter. Acute and chronic pain as well as wound complications are still important challenges in hemipelvectomy.

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.

Vaginal delivery after hemipelvectomy and pelvic radiotherapy for chondrosarcoma

Chondosarcoma of the proximal femur is a rare malignant disorder in women of (pre-) childbearing age, for which a radical resection through a hemipelvectomy could be indicated. We describe a case of a 36-year-old primigravida with a hemipelvectomy (2004) who had a history of radiotherapy of the pelvic and uterine regions after an atypical cartilaginous tumour. After an uncomplicated pregnancy, she had a spontaneous rupture of the membranes at 41+2 weeks and an uncomplicated vaginal delivery with physiological development of the infant. On the basis of the literature review, vaginal delivery after hemipelvectomy should be advocated and discussed with the patient and involved care providers. Women with radiotherapy in the pelvic and uterine areas have an increased risk of stillbirth, placental attachment disorders, impaired fetal growth, fetal malposition and preterm labour, but no association with prolonged rupture of the membranes has been described.

Femur performed better than tibia in autologous transplantation during hemipelvis reconstruction

BACKGROUND

Pelvic reconstruction after hemipelvectomy can greatly improve the weight-bearing stability of the supporting skeleton and improve patients' quality of life. Although an autograft can be used to reconstruct pelvic defects, the most suitable choice of autograft, i.e., the use of either femur or tibia, has not been determined. We aimed to analyze the mechanical stresses of a pelvic ring reconstructed using femur or tibia after hemipelvectomy using finite element (FE) analysis.

METHODS

FE models of normal and reconstructed pelvis were established based on computed tomography images, and the stress distributions were analyzed under physiological loading from 0 to 500 N in both intact and restored pelvic models using femur or tibia.

RESULTS

The vertical displacement of the intact pelvis was less than that of reconstructed pelvis, but there was no significant difference between the two reconstructed models. In FE analysis, the stress distribution of the intact pelvic model was bilaterally symmetric and the maximum stresses were located at the sacroiliac joint, arcuate line, ischiatic ramus, and ischial tuberosity. The maximum stress in each part of the reconstructed pelvis greatly exceeded that of the intact model. The maximum von Mises stress of the femur was 13.9 MPa, and that of the tibia was 6.41 MPa. However, the stress distribution was different in the two types of reconstructed pelvises. The tibial reconstruction model induced concentrated stress on the tibia shaft making it more vulnerable to fracture. The maximum stress on the femur was concentrated on the connections between the femur and the screws.

CONCLUSIONS

From a biomechanical point of view, the reconstruction of hemipelvic defects with femur is a better choice.

Hemipelvectomy: outcome in 84 dogs and 16 cats. A veterinary society of surgical oncology retrospective study

OBJECTIVE

To report clinical findings, perioperative complications and long-term outcome in dogs and cats that had hemipelvectomy surgery for treatment of neoplasia.

STUDY DESIGN

Multi-institutional retrospective case series.

ANIMALS

Dogs (n = 84) and cats (16).

METHODS

Medical records (January 2000 to December 2009) of dogs and cats that had hemipelvectomy at participating institutions were reviewed. Postoperative progress and current status of the patient at the time of the study was determined by either medical record review, or via telephone contact with the referring veterinarian or owner.

RESULTS

Complications were infrequent and usually minor. Hemorrhage was the main intraoperative complication; 2 dogs required blood transfusion. One dog developed an incisional hernia. In dogs, hemangiosarcoma had the worst prognosis with a median survival time (MST) of 179 days. MST for chondrosarcoma (1232 days), osteosarcoma (533 days), and soft tissue sarcoma (373 days) were not statistically different. Median disease-free interval (DFI) for local recurrence of all tumor types was 257 days. Cats had 75% survival at 1 year, which was significantly longer than dogs.

CONCLUSIONS

Survival times for most tumor types can be good, but surgical margins should be carefully evaluated to ensure complete tumor removal. Adjuvant therapies may be advisable particularly for dogs to reduce rates of local recurrence or distant metastasis.

Pelvic reconstruction with allogeneic bone graft after tumor resection

OBJECTIVES

: Pelvic reconstruction after tumor resection is challenging.

METHODS

A retrospective study had been preformed to compare the outcomes among patients who received pelvic reconstructive surgery with allogeneic bone graft after en bloc resection of pelvic tumors and patients who received en bloc resection only.

RESULTS

Patients without reconstruction had significantly lower functional scores at 3 months (10 vs. 15, P = 0.001) and 6 months after surgery (18.5 vs. 22, P = 0.0024), a shorter duration of hospitalization (16 day vs. 40 days, P < 0.001), and lower hospitalization costs (97,500 vs. 193,000 RMB, P < 0.001) than those who received pelvic reconstruction. Functional scores were similar at 12 months after surgery (21.5 vs. 23, P = 0.365) with no difference in the rate of complications between the two groups (P > 0.05).

CONCLUSIONS

: Pelvic reconstruction with allogeneic bone graft after surgical management of pelvic tumors is associated with satisfactory surgical and functional outcomes. Further clinical studies are required to explore how to select the best reconstruction method. Level of Evidence IV, Case Series.