Comparison of Prophylactic Intravenous Antibiotic Regimens After Endoprosthetic Reconstruction for Lower Extremity Bone Tumors: A Randomized Clinical Trial

Similar risks of complications and reoperation rates in proximal femur megaprostheses for oncological and non-oncological indications

PURPOSE

Proximal femur megaprostheses (PFMPs) are used to manage large bone defects in both non-oncological indications (NOI) and oncological indications (OI). However, little is known about the comparative risks of reoperation and functional outcomes between these groups. This study aimed to evaluate the cumulative incidences of reoperation and functional results of PFMPs between NOI and OI.

METHODS

This retrospective, monocentric cohort study included 109 implants between 2005 and 2020 (NOI, n = 42; OI, n = 67). Competing risk analysis was used to estimate and compare cumulative incidence of reoperation and complications, with death as a competing event. The Musculoskeletal Tumour Society Score (MSTS) was retrospectively assessed to compare functional outcomes.

RESULTS

The estimated cumulative incidence of reoperation at ten years did not statistically differ: 33.5% for NOI vs. 32.7% for OI (HR = 0.90, 95% CI (0.42-0.95), p = 0.791). The estimated cumulative incidence of complications at ten years did not statistically differ (HR = 1.50, 95%CI (0.80-2.80), p = 0.204). The MSTS score at ten years was significantly higher in the OI group (78.2% ± 19.5) compared to the NOI group (48.3% ± 10.9) (p = 0.012).

CONCLUSION

PFMPs for NOI demonstrate a comparable risk of reoperation to OI, but with lower long-term functional outcomes.

Endoprosthetic Reconstruction for Proximal Humerus Tumors

PURPOSE OF THE REVIEW

Anatomic and reverse endoprosthetic reconstruction are two common surgical options used after tumor resection of the proximal humerus. The purpose of this article is to provide an overview of the functional outcomes and complications of modern anatomic and reverse endoprostheses.

RECENT FINDINGS

The anatomic endoprosthesis has traditionally been a successful reconstructive technique as it provided a stable platform upon which the hand and elbow could function. However, the reverse endoprosthesis has gradually replaced the anatomic endoprosthesis given that its semi-constrained design affords greater stability. Patients with reverse endoprostheses have improved motion, patient-reported outcome scores, and revision-free implant survivorship compared to those with anatomic endoprostheses. Shoulder function may be further improved with a reverse allograft prosthetic composite (APC) due to reconstruction of the rotator cuff tendons or by transferring the latissimus dorsi and teres major tendons to recreate the function of the posterosuperior rotator cuff muscles. The short-term functional improvement observed with the use of an allograft reconstruction, however, may diminish with longer follow-up due to delayed graft complications, such as resorption, nonunion, and fracture. In most patients undergoing oncologic resection of the proximal humerus, the reverse endoprosthesis or reverse APC is recommended due to improved functional outcomes and reduced postoperative complications compared to other reconstructive techniques.

Periprosthetic Joint Infection Surrounding Lower-Extremity Endoprostheses After Tumor Resection: Causative Microorganisms, Effectiveness of DAIR, and Risk Factors for Treatment Failure

Background

Periprosthetic joint infection (PJI) surrounding an endoprosthesis after reconstruction of a lower extremity following tumor resection is a common complication, and the treatment of these infections is challenging and often requires multiple surgical interventions or even implant removal. Because there has been limited evidence to support treatment strategies and understanding of the epidemiology of the causative microorganisms, we analyzed the effectiveness of debridement, antibiotics, and implant retention (DAIR), risk factors for the failure of DAIR, and causative microorganisms in patients with a PJI surrounding a lower-extremity endoprosthesis after tumor resection.

Methods

A retrospective cohort study was conducted in a tertiary referral center for orthopaedic oncology. All patients treated between 2000 and 2018 for PJI surrounding a lower-extremity endoprosthesis after tumor resection were included. Treatment outcomes and risk factors for failure were analyzed in patients primarily treated with DAIR. Causative microorganisms were recorded. The minimum follow-up period was 2 years.

Results

Of the 337 patients who underwent endoprosthetic reconstruction of a lower extremity after tumor resection, 67 patients (20%) developed a PJI surrounding the endoprosthesis. Of those patients, 55 were primarily treated with DAIR. The functional cure rate of DAIR was 65% (36 of 55). A median of 2 debridements per patient was needed. Chemotherapy (odds ratio [OR], 3.1 [95% confidence interval (CI), 1.0 to 9.3]) and an erythrocyte sedimentation rate of >50 mm/hr at diagnosis (OR, 4.5 [95% CI, 1.3 to 15.4]) were associated with treatment failure. Nineteen patients (28%) had a polymicrobial infection.

Conclusions

Although sequential procedures are often needed, DAIR has acceptable clinical outcomes and should be considered, dependent on expected survival and the risk factors for treatment failure noted in this study.

Level of Evidence

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

Development of Machine Learning Models for Predicting the 1-Year Risk of Reoperation After Lower Limb Oncological Resection and Endoprosthetic Reconstruction Based on Data From the PARITY Trial

BACKGROUND

Oncological resection and reconstruction involving the lower extremities commonly lead to reoperations that impact patient outcomes and healthcare resources. This study aimed to develop a machine learning (ML) model to predict this reoperation risk.

METHODS

This study was conducted according to TRIPOD + AI. Data from the PARITY trial was used to develop ML models to predict the 1-year reoperation risk following lower extremity oncological resection and reconstruction. Six ML algorithms were tuned and calibrated based on fivefold cross-validation. The best-performing model was identified using classification and calibration metrics.

RESULTS

The polynomial support vector machine (SVM) model was chosen as the best-performing model. During internal validation, the SVM exhibited an AUC-ROC of 0.73 and a Brier score of 0.17. Using an optimal threshold that balances all quadrants of the confusion matrix, the SVM exhibited a sensitivity of 0.45 and a specificity of 0.81. Using a high-sensitivity threshold, the SVM exhibited a sensitivity of 0.68 and a specificity of 0.68. Total operative time was the most important feature for reoperation risk prediction.

CONCLUSION

The models may facilitate reoperation risk stratification, allowing for better patient counseling and for physicians to implement measures that reduce surgical risks.

Prophylactic Antibiotic Choice and Deep Infection in Lower Extremity Endoprosthetic Reconstruction: Comparison of Cefazolin, Cefazolin-Vancomycin, and Alternative Regimens

INTRODUCTION

Infection is a common mode of failure in lower extremity endoprostheses. The Prophylactic Antibiotic Regimens in Tumor Surgery trial reported that 5 days of cefazolin had no difference in surgical site infection compared with 24 hours of cefazolin. Our purpose was to evaluate infection rates of patients receiving perioperative cefazolin monotherapy, cefazolin-vancomycin dual therapy, or alternative antibiotic regimens.

METHODS

A single-center retrospective review was conducted on patients who received lower extremity endoprostheses from 2008 to 2021 with minimum 1-year follow-up. Three prophylactic antibiotic regimen groups were compared: cefazolin monotherapy, cefazolin-vancomycin dual therapy, and alternative regimens. The primary outcome was deep infection, defined by a sinus tract, positive culture, or clinical diagnosis. Secondary outcomes were revision surgery, microorganisms isolated, and superficial wound issues.

RESULTS

The overall deep infection rate was 10% (30/294) at the median final follow-up of 3.0 years (IQR 1.7 to 5.4). The deep infection rates in the cefazolin, cefazolin-vancomycin, and alternative regimen groups were 8% (6/72), 10% (18/179), and 14% (6/43), respectively ( P = 0.625). Patients not receiving cefazolin had an 18% deep infection rate (6/34) and 21% revision surgery rate (7/34) compared with a 9% deep infection rate (24/260) ( P = 0.13) and 12% revision surgery rate (31/260) ( P = 0.17) in patients receiving cefazolin. In those not receiving cefazolin, 88% (30/34) were due to a documented penicillin allergy, only two being anaphylaxis. All six patients in the alternative regimen group who developed deep infections did not receive cefazolin secondary to nonanaphylactic penicillin allergy.

CONCLUSION

The addition of perioperative vancomycin to cefazolin in lower extremity endoprosthetic reconstructions was not associated with a lower deep infection rate. Patients who did not receive cefazolin trended toward higher rates of deep infection and revision surgery, although not statistically significant. The most common reason for not receiving cefazolin was a nonanaphylactic penicillin allergy, highlighting the continued practice of foregoing cefazolin unnecessarily.

Prolonged prophylactic antibiotic use following megaprosthesis surgery may reduce periprosthetic infection

Introduction

Megaprostheses provide a reconstructive option for patients with bone loss after musculoskeletal tumor resection. However, the postoperative surgical site infection (SSI) risk is significant. This study aims to evaluate outcomes of extended postoperative antibiotic regimens in patients after megaprosthesis surgery and gather insight into strategies to minimize SSI.

Methods

This retrospective cohort study evaluated patients who underwent megaprosthesis surgery by a single surgeon at a single center from 2014 to 2022. Patient demographics, comorbidities, cancer treatment details, and antibiotic regimens were collected. Excluded were patients with less than 1 year of follow-up, active infection at time of surgery, non-healing wounds unrelated to SSI, and preoperative antibiotic regimens secondary to being immunocompromised. Measures of interest included the development of SSI within 1 year of surgery and development of antibiotic-related complications.

Results

Included were 49 patients, with a mean age of 61.2 ± 2.0 years and a mean BMI of 29.4 ± 7.0. The mean drain duration was 6.5 days (standard deviation [SD], 6.9 days), and the mean intravenous antibiotic administration duration was 6.4 days (SD, 6.9 days). The median time to drain removal was five days, and the median time for intravenous antibiotic cessation was five days. The mean total antibiotic administration duration (intravenous and oral) was 25.4 days (SD, 13.4 days). Only 1 patient in the included cohort (2.04 %) developed an SSI requiring operative intervention. No other patient within the cohort experienced an antibiotic-related complication.

Discussion

This study suggests that the site's current protocol for managing post-megaprosthesis antibiotic prophylaxis based on drain duration and incision healing status has resulted in a low rate of SSI and antibiotic-related complications. Further research is needed to validate these findings and gain additional insights into managing antibiotic prophylaxis after megaprosthesis surgery.

Surgical site infections after sarcoma resections in the peripelvic region: do we need perioperative antibiotic prophylaxis?

Introduction

Surgical site infections (SSI) are one of the most common complications after extensive sarcoma resections and represent a daily challenge. SSI occur in up to 50% of cases particularly in the peripelvic area. One possible approach to reduce infection rate is perioperative antibiotic prophylaxis. The aim of this study therefore was to investigate the influence of perioperative antibiotic prophylaxis on the infection rate and the possible influence of location-specific antibiotic prophylaxis with ampicillin/sulbactam.

Methods

This monocentric retrospective study included 366 patients who underwent sarcoma resections in the groin, proximal thigh, or gluteal region. All patients were operated on by 2 surgeons after neoadjuvant pretreatment if necessary. 3 groups of patients were defined. Group 1: In 60.4% of all cases, antibiotic prophylaxis was administered with cephalosporins (also clindamycin in case of penicillin allergy). Group2: In 9.8% of cases, ampicillin/sulbactam was used. Group 3: 29.8% of patients did not receive any antibiotic prophylaxis.

Results

In 31.1% of treated cases, antibiotic therapy was prolonged due to extended tumor resections. Postoperative infections occurred in 23.2% (85 cases), in 77 cases within the first 90 days (on average after 20 days). The median operating time, blood loss was higher, and tumor size were significantly larger in cases with infections, compared to patients without infection. In group 1 and 2 with perioperative single-shot prophylaxis, infection occurred in 24.1% of cases, compared to 13.5% of cases without prophylaxis (group 3) (p= 0.032). In the patients with prolonged antibiotic therapy, infection occurred in 31.6% of cases, compared to 16.3% of cases without prolongation (p< 0.001). In the group 2, infection occurred in 19.4% of cases compared to 24.9% of cases in the group 1 (p= 0.479). In the multivariate analysis, surgery time longer 80 min, blood substitution, neoadjuvant radio- and chemotherapy proved to be a risk factor for SSI.

Discussion

Region adapted perioperative antibiotic prophylaxis may reduce the risk of infection after extended sarcoma resection in the peripelvic area. However, the particular bacterial spectrum of this anatomic region should be taken into account when deciding which antibiotics to use.

Postoperative challenges addressed through nursing care of patients receiving lower extremity tumor prosthesis

BACKGROUND

Patients with primary Bone Sarcoma and Giant Cell Tumors in the lower extremities often require major surgery involving tumor prostheses. The postoperative course for this patient group can be complex and influenced by various factors and challenges that demand careful nursing care. This study aims to identify challenges related to the nursing care of individuals with primary bone tumors following surgery for tumor prostheses in the lower extremities.

METHODS

A retrospective cohort study of 15 patients treated at Rigshospitalet, Copenhagen, Denmark, between November 5. 2016, and April 1. 2020 was conducted by medical record review, focusing on challenges related to postoperative nursing care. All patients with the surgery code "Bone Excision" were identified within the surgery booking system and screened for eligibility.

RESULTS

Patients experienced postoperative challenges such as severe pain, prolonged time to mobilization (mean: 4 days), and defecation (mean: 5 days). The mean length of stay at the Rigshospitalet was 13 days. Furthermore, eleven patients (73%) reported disrupted sleep and nausea.

CONCLUSION

Patients undergoing tumor prosthesis surgery in the lower extremities face considerable postoperative challenges that contribute to a prolonged hospital stay. These challenges, including severe pain, delayed mobilization, and gastrointestinal issues, significantly impact recovery. The findings highlight the urgent need for targeted nursing interventions to address these issues effectively. Enhanced pain management protocols, early mobilization strategies, and comprehensive postoperative care plans are essential to improve patient outcomes and reduce the length of hospital stays. Addressing these challenges through dedicated nursing care is crucial for optimizing the recovery process for patients receiving lower extremity tumor prostheses.

Comparison of Different Fusion Radiomics for Predicting Benign and Malignant Sacral Tumors: A Pilot Study

Differentiating between benign and malignant sacral tumors is crucial for determining appropriate treatment options. This study aims to develop two benchmark fusion models and a deep learning radiomic nomogram (DLRN) capable of distinguishing between benign and malignant sacral tumors using multiple imaging modalities. We reviewed axial T2-weighted imaging (T2WI) and non-contrast computed tomography (NCCT) of 134 patients pathologically confirmed as sacral tumors. The two benchmark fusion models were developed using fusion deep learning (DL) features and fusion classical machine learning (CML) features from multiple imaging modalities, employing logistic regression, K-nearest neighbor classification, and extremely randomized trees. The two benchmark models exhibiting the most robust predictive performance were merged with clinical data to formulate the DLRN. Performance assessment involved computing the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, accuracy, negative predictive value (NPV), and positive predictive value (PPV). The DL benchmark fusion model demonstrated superior performance compared to the CML fusion model. The DLRN, identified as the optimal model, exhibited the highest predictive performance, achieving an accuracy of 0.889 and an AUC of 0.961 in the test sets. Calibration curves were utilized to evaluate the predictive capability of the models, and decision curve analysis (DCA) was conducted to assess the clinical net benefit of the DLR model. The DLRN could serve as a practical predictive tool, capable of distinguishing between benign and malignant sacral tumors, offering valuable information for risk counseling, and aiding in clinical treatment decisions.

Antibiotic prophylaxis for surgical wound infections in clean and clean-contaminated surgery: an updated systematic review and meta-analysis

BACKGROUND

The efficacy and necessity of prophylactic antibiotics in clean and clean-contaminated surgery remains controversial.

METHODS

The studies were screened and extracted using databases including PubMed, Embase, Cochrane Library, Web of Science, and Clinical Trials.gov according to predefined eligibility criteria. Randomized controlled trials (RCTs) comparing the effect of preoperative and postoperative prophylactic antibiotic use on the incidence of surgical site infections (SSIs) in patients undergoing any clean or clean-contaminated surgery.

RESULTS

A total of 16 189 participants in 48 RCTs were included in the primary meta-analysis following the eligibility criteria. The pooled odds ratio (OR) for SSI with antibiotic prophylaxis versus placebo was 0.60 (95% CI: 0.53-0.68). The pooled OR among gastrointestinal, oncology, orthopedics, neurosurgery, oral, and urology surgery was 3.06 (95% CI: 1.05-8.91), 1.16 (95% CI: 0.89-1.50), 2.04 (95% CI: 1.09-3.81), 3.05 (95% CI: 1.25-7.47), 3.55 (95% CI: 1.78-7.06), and 2.26 (95% CI: 1.12-4.55), respectively. Furthermore, the summary mean difference (MD) for patients' length of hospitalization was -0.91 (95% CI: -1.61, -0.16). The results of sensitivity analyses for all combined effect sizes showed good stability.

CONCLUSION

Antibiotics are both effective, safe, and necessary in preventing surgical wound infections in clean and clean-contaminated procedures, attributed to their reduction in the incidence of surgical site infections as well as the length of patient hospitalization.

Assessing morinidazole for surgical site infection in class III wounds prevention: a multi-centre, randomized, single-blind, parallel-controlled study

INTRODUCTION

Surgical site infections (SSIs) are significant postoperative risks; antibiotic prophylaxis is crucial due to the presence of anaerobic bacteria. This study investigated the efficacy and safety of a novel nitroimidazole, morinidazole, in SSI reduction in class III wounds, as there is currently a lack of evidence in the existing literature.

METHODS

A multi-centre randomized clinical trial was conducted from December 2020 to October 2022 in the general surgery departments of 12 tertiary hospitals in China, including 459 patients in two treatment groups using morinidazole plus ceftriaxone or ceftriaxone alone. Efficacy and safety were evaluated including SSI incidence, adverse events, and compliance. Statistical analysis employed SAS 9.4 software. Data analysis was performed from February to May 2023.

RESULTS

A total of 440 participants (median (interquartile range, IQR) age, 63.0 (54.0, 70.0) years; 282 males (64.09%); 437 patients were of Han race (99.32%) and were randomized. The experimental group exhibited a significantly lower SSI rate compared with the control group (31 (14.49%) vs 52 (23.01%); risk difference, 1.76%, 95% confidence interval (CI) 1.08-2.88%; P=0.0224). The superficial incisional site infections revealed a marked reduction in the experimental group (12 (5.61%) vs 31 (13.37%); risk difference, 2.68%; 95% CI 1.34-5.36%; P=0.0042). Non-surgical site infections, severe postoperative complications, and total adverse events showed no statistically significant differences between the groups (P>0.05).

CONCLUSION

The significant decrease in SSI rates and superficial incisional infections demonstrates morinidazole to be a valuable prophylactic antibiotic. Our findings provide valuable insights for clinical practice, where this new-generation nitroimidazole can play a crucial role in SSI prevention.

Preventing Surgical Site Infections in the Era of Escalating Antibiotic Resistance and Antibiotic Stewardship

Importance

According to the Centers for Disease Control and Prevention and governing bodies within the American College of Surgeons, the administration of antibiotics as prophylaxis against infection prior to a planned elective procedure is, with rare exception, routinely recommended. The goal of "getting to zero" infections remains a high priority for policymakers, practitioners, and certainly for patients.

Observations

Despite the many advances in surgical technique, skin decontamination, sterile procedure, and enhanced recovery programs, surgical site infections continue to adversely affect procedures as diverse as dental implant surgery, joint arthroplasty, and major abdominal surgery. Although surgical site infection rates are at historically low levels, progress has stalled in recent reporting periods and such infections remain disabling, costly, and occasionally lethal. Stakeholders in the field, including surgeons, infectious diseases specialists, and industry, advocate for strategies emphasizing greater levels of intraoperative sterility or broader-spectrum antibiotic coverage as the most appropriate path forward.

Conclusions and Relevance

The current emphasis on ever-increasing levels of intraoperative sterility and extended-spectrum antibiotic use are not sustainable long-term solutions. Continuing to escalate these approaches may contribute to unintended consequences including antimicrobial resistance. Principles of antimicrobial stewardship and microbiome sciences can be applied to inform a more effective and sustainable approach to infection prevention in the field of surgery.

Distraction Osteogenesis Reconstruction Following Resection of Bone Sarcomas: Surgical, Functional, and Oncological Outcomes from a Prospective Trial Analysis

BACKGROUND

While sustainable long-term function has been established for biological reconstruction with distraction osteogenesis (DO) following osseous resections, there is a paucity of published data informing surgeons and patients on important milestones in the reconstructive process. The objectives of this study were to determine when to expect complete bone healing and full weight-bearing as well as to quantify the influence of chemotherapy on the osseous regeneration process.

METHODS

Prospectively, pathological and clinical data were collected for 30 consecutive patients who underwent primary or secondary DO-based reconstruction following osseous resection from 2018 to 2021. Serial radiographs indicated the times to cortex formation and full union. An unpaired t test was used to compare the time required for full bone remodeling of segments transported with and without concurrent chemotherapy.

RESULTS

The average resection length was 13.6 cm (range, 4 to 22 cm). Patients underwent an average of 6.1 procedures (range, 1 to 14 procedures). Half (50%) of all procedures were planned, while half were unplanned procedures. All patients achieved full, independent weight-bearing at a median of 12 months (interquartile range [IQR], 9 to 16 months). For the 34 segments transported concurrently with chemotherapy, the mean bone healing index (BHI) was 2.3 ± 0.7, and the mean BHI was 1.2 ± 0.4 for the 25 segments without chemotherapy at any point during their transport (p < 0.0001).

CONCLUSIONS

All 30 patients achieved full bone healing and independent weight-bearing at a median of 1 year postoperatively and continued to show functional improvement afterward. Surgeons and patients can expect bone healing to be nearly twice as fast for segments transported after completion of systemic chemotherapy compared with segments transported concurrently with adjuvant chemotherapy.

LEVEL OF EVIDENCE

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

How Research Improves Clinical Care: The Case for Orthopaedic Surgeon Research Leadership and Collaboration: AOA Critical Issues Symposium

ABSTRACT

Improving the performance and impact of orthopaedic research is a critical leadership challenge. Musculoskeletal (MSK) conditions are a leading cause of disability worldwide, for which research investment and performance lags far behind the burden of disease. In the United States, MSK disorders account for the highest health care costs, have increased in incidence at the fastest rate, and exceed the combined costs of cardiovascular diseases and neoplasms. Despite the cost to society, the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), with primary responsibility for MSK research, receives <1.4% of the funds allocated to the National Institutes of Health (NIH). Although orthopaedic surgeons are leading providers of MSK clinical care, the dearth of orthopaedic clinician-scientists also greatly reduces representation of MSK scientific and clinical expertise among academic and scientific leaders. The goals of this symposium were to highlight the critical need for greater prioritization and investment in orthopaedic research and to engage orthopaedic leaders in addressing these needs. Compelling stories of research success from 3 orthopaedic chairs were featured to highlight how orthopaedic surgeon leadership in bench-to-bedside research substantially advances MSK clinical care. Seminar participants also emphasized the need to improve evidence-based clinical practice for which multicenter prospective cohort and registry studies represent opportunities for broader involvement. Prioritization of orthopaedic clinician-scientist development and formation of multidisciplinary partnerships with basic and translational scientists were emphasized as critical needs to advance MSK health. It is critical for orthopaedic chairs to "be invested in" and to "invest in" the success of orthopaedic research. This investment includes developing a professional climate that values research achievement and collaboration as well as implementing strategies to support and sustain research success. Finally, orthopaedic leaders need to advocate for federal research funding to be proportional to the economic burden of disease for which MSK conditions carry the highest current and projected costs. With health-care costs accounting for nearly one-fifth of the U.S. economy, increasing the investment in orthopaedic research to reduce the prevalence, disability, and morbidity from MSK disease needs to be a top orthopaedic and national leadership priority.

The microbial profile of infected endoprosthetic reconstructions after wide excision for patients with musculoskeletal tumors: A call for pathogen-based practices

BACKGROUND AND OBJECTIVES

Periprosthetic infection is a devastating complication following endoprosthetic reconstruction. This study utilized a large database of endoprostheses to describe the incidence, risk factors, and microbial profile of such infections to better catalogue and understand these catastrophic events.

METHODS

A retrospective review of endoprosthetic reconstructions for an oncologic indication from January 1, 1981 to December 31, 2020 was performed. Demographic, oncologic, procedural and outcome data was analyzed. Multivariable logistic regression was used to identify potential risk factors for infection with significance defined as p < 0.05.

RESULTS

Forty four out of 712 (6.2%) reconstructions resulted in infection at a mean time of 39.9 ± 44.5 months. Revision surgery (odds ratio [OR] 6.14, p < 0.001) or having a postoperative wound complication (OR 7.67, p < 0.001) were significantly associated with infection. Staphylococcus aureus and Staphylococcus epidermidis were the most commonly cultured organisms at a rate of 34.1% (15/44) and 22.7% (10/44), respectively. Ten infections resulted in amputation; five due to antimicrobial-resistant infections and three due to polymicrobial infections.

CONCLUSION

Understanding the microbial profile of patients undergoing endoprosthetic reconstruction is paramount. This study demonstrates a relatively high rate of polymicrobial and antibiotic-resistant infections that portend worse outcomes, thus suggesting that pathogen-specific infectious practices may be warranted.

LEVEL OF EVIDENCE

Retrospective cohort study, level III.

Closed-incision negative-pressure wound therapy (ciNPWT) to minimize wound-related complications in lower limb reconstruction after bone tumor resection: preliminary proof-of-concept study

AIMS

The purpose of this study was to compare the impact of postoperative closed-incision negative-pressure wound therapy (ciNPWT) and conventional dressings in wound-related complications after bone tumor resection and reconstruction.

PATIENTS AND METHODS

A total of 50 patients with bone tumors and clinical indication for wide resection and reconstruction were included and divided into two groups (A and B). Bone defect reconstructions were achieved with modular endoprosthesis or biologic techniques, mainly involving allografts with free vascularized fibula. Group A received ciNPWT, and Group B conventional dressings. Wound-related complications, including wound dehiscence, persistent wound leakage, surgical site infections (SSIs), and causes for surgical revision, were assessed.

RESULTS

Nineteen patients were included in Group A and 31 in Group B. No significant differences were found between groups regarding epidemiologic and clinical presentation features, contrarily to reconstructive options, which were significantly different between both (Fisher = 10,100; p = 0.005). Additionally, Group A presented lower wound dehiscence rate (0 vs. 19.4%; χ2(1) = 4.179; p = 0.041), SSI rate (0 vs. 19.4%; χ2(1) = 4.179; p = 0.041), and surgical revision rate (5.3% vs. 32.3%; χ2(1) = 5.003; p = 0.025) compared to Group B.

CONCLUSIONS

This is the first study reporting the impact of ciNPWT after bone tumor resection and reconstruction, and its results support a potential role for this technique in diminishing postoperative wound complications and SSIs. A multicentric randomized controlled trial may help clarify the role and impact of ciNPWT after bone tumor resection and reconstruction.

Artificial intelligence-based radiomics in bone tumors: Technical advances and clinical application

Radiomics is the extraction of predefined mathematic features from medical images for predicting variables of clinical interest. Recent research has demonstrated that radiomics can be processed by artificial intelligence algorithms to reveal complex patterns and trends for diagnosis, and prediction of prognosis and response to treatment modalities in various types of cancer. Artificial intelligence tools can utilize radiological images to solve next-generation issues in clinical decision making. Bone tumors can be classified as primary and secondary (metastatic) tumors. Osteosarcoma, Ewing sarcoma, and chondrosarcoma are the dominating primary tumors of bone. The development of bone tumor model systems and relevant research, and the assessment of novel treatment methods are ongoing to improve clinical outcomes, notably for patients with metastases. Artificial intelligence and radiomics have been utilized in almost full spectrum of clinical care of bone tumors. Radiomics models have achieved excellent performance in the diagnosis and grading of bone tumors. Furthermore, the models enable to predict overall survival, metastases, and recurrence. Radiomics features have exhibited promise in assisting therapeutic planning and evaluation, especially neoadjuvant chemotherapy. This review provides an overview of the evolution and opportunities for artificial intelligence in imaging, with a focus on hand-crafted features and deep learning-based radiomics approaches. We summarize the current application of artificial intelligence-based radiomics both in primary and metastatic bone tumors, and discuss the limitations and future opportunities of artificial intelligence-based radiomics in this field. In the era of personalized medicine, our in-depth understanding of emerging artificial intelligence-based radiomics approaches will bring innovative solutions to bone tumors and achieve clinical application.

Endoprosthetic reconstruction for lower extremity soft tissue sarcomas with bone involvement

BACKGROUND AND OBJECTIVES

Bone resection and endoprosthetic reconstruction (EPR) in the setting of soft tissue sarcoma (STS) management is rare and incurs unique challenges. We aim to report on the surgical and oncological outcomes of this relatively previously undocumented cohort.

METHODS

This is a single-center retrospective review of prospectively collected data for patients who required EPRs following resection of STSs of the lower extremity. Following inclusion criteria, we assessed 29 cases of EPR for primary STS of the lower limb.

RESULTS

The mean age was 54 years (range 18-84). Of the 29 patients, there were 6 total femur, 11 proximal femur, 4 intercalary, and 8 distal femur EPRs. Fourteen of 29 patients (48%) underwent re-operations for surgical complications, with 9 relating to infection (31%). When a matched cohort analysis was performed comparing our cohort to STSs that did not necessitate EPR, a reduced rate of overall survival and metastasis-free survival was found in those requiring EPR.

CONCLUSION

This series identifies a high rate of complication from EPRs performed for STS. Patients should be cautioned about the high rate of infection, surgical complications, and lower overall survival in this setting.

Prophylactic antibiotics for massive endoprostheses in orthopaedic oncology

The recently published Prophylactic Antibiotic Regimens In Tumor Surgery (PARITY) trial found no benefit in extending antibiotic prophylaxis from 24 hours to five days after endoprosthetic reconstruction for lower limb bone tumours. PARITY is the first randomized controlled trial in orthopaedic oncology and is a huge step forward in understanding antibiotic prophylaxis. However, significant gaps remain, including questions around antibiotic choice, particularly in the UK, where cephalosporins are avoided due to concerns of Clostridioides difficile infection. We present a review of the evidence for antibiotic choice, dosing, and timing, and a brief description of PARITY, its implication for practice, and the remaining gaps in our understanding.

Surgical Site Infection in Patients Managed with an Endoprosthesis for the Treatment of Cancer: Evaluation of Patient, Disease, and Index Surgical Factors

BACKGROUND

Surgical site infection (SSI) after segmental endoprosthetic reconstruction in patients treated for oncologic conditions remains both a devastating and a common complication. The goal of the present study was to identify variables associated with the success or failure of treatment of early SSI following the treatment of a primary bone tumor with use of a segmental endoprosthesis.

METHODS

The present study used the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) data set to identify patients who had been diagnosed with an SSI after undergoing endoprosthetic reconstruction of a lower extremity primary bone tumor. The primary outcome of interest in the present study was a dichotomous variable: the success or failure of infection treatment. We defined failure as the inability to eradicate the infection, which we considered as an outcome of amputation or limb retention with chronic antibiotic suppression (>90 days or ongoing therapy at the conclusion of the study). Multivariable models were created with covariates of interest for each of the following: surgery characteristics, cancer treatment-related characteristics, and tumor characteristics. Multivariable testing included variables selected on the basis of known associations with infection or results of the univariable tests.

RESULTS

Of the 96 patients who were diagnosed with an SSI, 27 (28%) had successful eradication of the infection and 69 had treatment failure. Baseline and index procedure variables showing significant association with SSI treatment outcome were moderate/large amounts of fascial excision ≥1 cm2) (OR, 10.21 [95% CI, 2.65 to 46.21]; p = 0.001), use of local muscle/skin graft (OR,11.88 [95% CI, 1.83 to 245.83]; p = 0.031), and use of a deep Hemovac (OR, 0.24 [95% CI, 0.05 to 0.85]; p = 0.041). In the final multivariable model, excision of fascia during primary tumor resection was the only variable with a significant association with treatment outcome (OR, 10.21 [95% CI, 2.65 to 46.21]; p = 0.018).

CONCLUSIONS

The results of this secondary analysis of the PARITY trial data provide further insight into the patient-, disease-, and treatment-specific associations with SSI treatment outcomes, which may help to inform decision-making and management of SSI in patients who have undergone segmental bone reconstruction of the femur or tibia for oncologic indications.

LEVEL OF EVIDENCE

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

Surgical Site Infection Is Not Associated with 1-Year Progression-Free Survival After Endoprosthetic Reconstruction for Lower-Extremity Osteosarcoma: A Secondary Analysis of PARITY Study Data

BACKGROUND

Although there is evidence suggesting that postoperative infection confers a survival benefit in osteosarcoma treated with resection and endoprosthetic reconstruction, there have been no prospective studies to date to support these findings. This secondary analysis of Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) study data examines the relationship between surgical site infection (SSI) and disease progression within 12 months after limb salvage surgery.

METHODS

The PARITY trial was an international, multicenter, prospective randomized controlled trial of 604 patients who underwent resection of a lower-extremity bone tumor and endoprosthetic reconstruction. Our primary outcome was progression-free survival (PFS) at 1 year following surgery among the patients with osteosarcoma. Subgroup analyses by disease stage at presentation and infection severity were also performed. Cox proportional hazard models were employed to examine the association between clinical and tumor characteristics, SSI, and PFS. Kaplan-Meier analysis was used to determine the effect of SSI on PFS.

RESULTS

The 274 PARITY patients with osteosarcoma were included in this secondary analysis. Thirty-two (11.7%) of the patients presented with metastasis at baseline; 53 (19.3%) of the patients developed an SSI. There was no difference in 1-year PFS between patients with and without SSI. There was no decreased risk of disease progression at 1 year in patients with localized disease at baseline who developed an SSI (hazard ratio [HR] = 1.21; 95% confidence interval [CI] = 0.64 to 2.28). Infection was associated with increased disease progression at 1 year in patients with baseline metastases (HR = 4.26; 95% CI = 1.11 to 16.3).

CONCLUSIONS

No positive association was detected between postoperative infection and PFS at 1 year following surgery in this secondary analysis of prospective data. However, this analysis suggests infection could be a risk factor for early disease progression in patients with baseline metastases, and future investigations may better elucidate the association between disease burden and the host immune response to advance immunotherapeutic strategies for osteosarcoma.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Operative Treatment and Outcomes of Pediatric Patients with an Extremity Bone Tumor: A Secondary Analysis of the PARITY Trial Data

BACKGROUND

Osteosarcoma and Ewing sarcoma are the 2 most common primary bone sarcomas, occurring predominantly in pediatric patients, with the incidence of osteosarcoma correlating with periods of peak bone-growth velocity. Although survival outcomes have plateaued over the past several decades, ongoing treatment advances have improved function, decreased infection rates, and improved other clinical outcomes in patients with bone tumors. Recently, the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial addressed the serious problem of surgical site infection (SSI) and the lack of consensus regarding the appropriate prophylactic postoperative antibiotic regimen. The objective of the present secondary analysis of the PARITY trial was to characterize the modern treatment and surgical and oncologic outcomes of pediatric patients with bone tumors at 1 year postoperatively.

METHODS

The PARITY trial included patients ≥12 years old with a bone tumor or soft-tissue sarcoma that was invading the femur or tibia, necessitating osseous resection and endoprosthetic reconstruction. This pediatric subanalysis of the PARITY trial data included all PARITY patients ≤18 years old. As in the main PARITY study, patients were randomized to either a 5-day or 1-day course of postoperative antibiotic prophylaxis. The primary outcome measure was the development of an SSI within 1 year, and secondary outcomes included antibiotic-related adverse events, unplanned additional operations, local recurrence, metastasis, and death.

RESULTS

A total of 151 patients were included. An adjudicated SSI occurred in 27 patients (17.9%). There was no difference in the rate of any SSI between the 5-day and 1-day antibiotic groups (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.4 to 1.9; p = 0.82). Antibiotic-related complications occurred in 13 patients (8.6%), with no difference noted between groups (HR, 0.46; 95% CI, 0.2 to 1.4; p = 0.18). A total of 45 patients (29.8%) required a return to the operating room within the first postoperative year, which corresponded with a 68.8% reoperation-free rate of survival at 1 year when accounting for competing risks. The most common reason for reoperation was infection (29 of 45; 64.4%). A total of 7 patients (4.6%) required subsequent amputation of the operative extremity, and an additional 6 patients (4.0%) required implant revision within 12 months. A total of 36 patients (23.8%) developed metastases, and 6 patients (4.0%) developed a local recurrence during the first postoperative year. A total of 11 patients (7.3%) died during the study period. There were no significant differences in oncologic outcomes between the 5-day and 1-day antibiotic groups (HR, 0.97; 95% CI, 0.5-1.8; p = 0.92).

CONCLUSIONS

There were no significant differences in surgical or oncologic outcomes between pediatric patients who underwent a 1-day versus 5-day antibiotic regimen following endoprosthetic reconstruction in the PARITY trial. Surgeons should be aware of and counsel patients and caregivers regarding the 30% rate of reoperation and the risks of infection (17.9%), death (7.3%), amputation (4.6%), and implant revision (4%) within the first postoperative year.

LEVEL OF EVIDENCE

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

Patient and Surgical Risk Factors for Surgical Site Infection in Lower-Extremity Oncological Endoprosthetic Reconstruction: A Secondary Analysis of the PARITY Trial Data

BACKGROUND

The specific risk factors for surgical site infection (SSI) in orthopaedic oncology patients undergoing endoprosthetic reconstruction have not previously been evaluated in a large prospective cohort. In the current study, we aimed to define patient- and procedure-specific risk factors for SSI in patients who underwent surgical excision and endoprosthetic reconstruction for lower-extremity bone or soft-tissue tumors using the prospectively collected data of the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial.

METHODS

PARITY was a multicenter, blinded, randomized controlled trial with a parallel 2-arm design that aimed to determine the effect of a long duration (5 days) versus short duration (24 hours) of postoperative prophylactic antibiotics on the rate of SSI in patients undergoing surgical excision and endoprosthetic reconstruction of the femur or tibia. In this secondary analysis of the PARITY data, a multivariate Cox proportional hazards regression model was constructed to explore predictors of SSI within 1 year postoperatively.

RESULTS

A total of 96 (15.9%) of the 604 patients experienced an SSI. Of the 23 variables analyzed in the univariate analysis, 4 variables achieved significance: preoperative diagnosis, operative time, volume of muscle excised, and hospital length of stay (LOS). However, only hospital LOS was found to be independently predictive of SSI in the multivariate regression analysis (hazard ratio per day = 1.03; 95% confidence interval = 1.01 to 1.05; p < 0.001). An omnibus test of model coefficients demonstrated that the model showed significant improvement over the null model (χ2 = 78.04; p < 0.001). No multicollinearity was found.

CONCLUSIONS

This secondary analysis of the PARITY study data found that the only independent risk factor for SSI on multivariate analysis was hospital LOS. It may therefore be reasonable for clinicians to consider streamlined discharge plans for orthopaedic oncology patients to potentially reduce the risk of SSI.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Pediatric and Adult Patients Have Similar Functional Improvement After Endoprosthetic Reconstruction of Lower-Extremity Tumors

BACKGROUND

Although the treatment of lower-extremity bone tumors is similar between adult and pediatric patients, differences in outcomes are unknown. Outcomes for lower-extremity oncologic reconstruction have been challenging to study because of the low incidence and heterogeneity in disease and patient characteristics. The PARITY (Prophylactic Antibiotic Regimens in Tumor Surgery) trial is the largest prospective data set assembled to date for patients with lower-extremity bone tumors and presents an opportunity to investigate differences in outcomes between these groups.

METHODS

Patient details were acquired from the prospectively collected PARITY trial database. The 1993 Musculoskeletal Tumor Society (MSTS-93) and Toronto Extremity Salvage Score (TESS) questionnaires were administered preoperatively and at 3, 6, and 12 months postoperatively. Continuous outcomes were compared between groups with use of the Student t test, and dichotomous outcomes were compared with use of the Pearson chi-square test.

RESULTS

A total of 150 pediatric and 447 adult patients were included. Pediatric patients were more likely than adult patients to have a primary bone tumor (146 of 150 compared with 287 of 447, respectively; p < 0.001) and to have received adjuvant chemotherapy (140 of 149 compared with 195 of 441, respectively; p < 0.001). Reoperation rates were not significantly different between age groups (45 of 105 pediatric patients compared with 106 of 341 adult patients; p ≤ 0.13). Pediatric patients had higher mean MSTS-93 scores (64.7 compared with 53.8 among adult patients; p < 0.001) and TESS (73.4 compared with 60.4 among adult patients; p < 0.001) at baseline, which continued to 1 year postoperatively (mean MSTS-93 score, 82.0 compared with 76.8 among adult patients; p = 0.02; mean TESS, 87.7 compared with 78.6 among adult patients; p < 0.001). Despite the differences in outcomes between cohorts, pediatric and adult patients demonstrated similar improvement in MSTS-93 scores (mean difference, 17.4 and 20.0, respectively; p = 0.48) and TESS (mean difference, 14.1 and 14.7, respectively; p = 0.83) from baseline to 1 year postoperatively.

CONCLUSIONS

Pediatric patients had significantly better functional outcomes than adult patients at nearly all of the included postoperative time points; however, pediatric and adult patients showed similar mean improvement in these outcomes at 1 year postoperatively. These findings may be utilized to help guide the postoperative expectations of patients undergoing oncologic reconstruction.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Open Versus Core Needle Biopsy in Lower-Extremity Sarcoma: Current Practice Patterns and Patient Outcomes

BACKGROUND

Historically, open biopsy (OB) was the gold standard for sarcoma diagnosis. Core needle biopsy (CNB) has become increasingly common. There are limited data evaluating how the type of biopsy impacts definitive surgical resection or postoperative outcomes. The aims of this study were to (1) characterize current international biopsy practice patterns, and (2) evaluate how the type of biopsy performed impacts the resection surgery, infection risk, oncological complications, and patient-reported functional outcome scores.

METHODS

This study was a preplanned secondary analysis of the prospective, multicenter PARITY (Prophylactic Antibiotic Regimens in Tumor Surgery) study. Patients with a benign diagnosis, metastatic disease, or no biopsy prior to surgery were excluded. Prospectively collected demographic, biopsy, surgical, and outcome variables were analyzed, and differences between patients undergoing OB and CNB were assessed. Parametric and nonparametric tests were used to compare variables between groups, and the Cox proportional hazards method was used to compare infection-related and oncological outcomes at 1 year. Median functional outcome scores at 1 year were compared.

RESULTS

Four hundred and sixty-four patients met the inclusion criteria. Data were collected from 48 sarcoma centers in 12 countries. CNB was the more utilized biopsy modality overall (57.5%). OB was more common in the U.S. and Canada. The median operative time was significantly longer for patients who underwent OB (324 versus 260 minutes; p < 0.001). Significantly more skin (p < 0.001) and fascial tissue (p < 0.001) were excised in the OB group, which also had a lower rate of primary closure (86.3% versus 92.9%; p = 0.03). There were no differences in surgical site infection or oncological outcomes between the groups at 1-year follow-up.

CONCLUSIONS

CNB was the more common biopsy modality in the PARITY study in most countries. However, OB was more common in the U.S. and Canada. Patients undergoing OB had longer operative times, more excised tissue, and lower rates of primary closure, but this did not translate to differences in infection rates or oncological outcomes, including local recurrence.

LEVEL OF EVIDENCE

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

Surgical Duration Is Independently Associated with an Increased Risk of Surgical Site Infection and May Not Be Mitigated by Prolonged Antibiotics: A Secondary Analysis of the PARITY Trial of Infection After Lower-Extremity Endoprosthetic Reconstruction for Bone Tumors

BACKGROUND

Infection after tumor resection and endoprosthetic reconstruction is a potentially limb-threatening complication. The duration of surgery has been shown to be a risk factor for infection, but the ability of an extended duration of postoperative prophylactic antibiotics to potentially minimize that risk has not been specifically studied. The objective of this study was to determine whether extended postoperative antibiotic therapy protects against surgical site infection (SSI) in the setting of prolonged surgical duration in patients undergoing endoprosthetic reconstruction after tumor resection.

METHODS

This study was a planned secondary analysis of the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial data set. Patients in the PARITY trial were randomized to receive 24 hours or 5 days of postoperative prophylactic antibiotics. The current study assessed the risk of SSI in those cohorts on the basis of surgical duration. A multivariable regression model was used to examine the adjusted effects of the duration of surgery on SSI, after controlling for other significant risk factors and potential confounders.

RESULTS

All 604 patients who had been included in the final data analysis in the PARITY trial were also included in this secondary analysis. Those who sustained an SSI had a greater mean duration of surgery (6.2 hours) compared with those who did not sustain an SSI (4.9 hours, p < 0.0001). There was no specific time point at which the risk of infection significantly increased. Extended postoperative prophylactic antibiotic therapy did not appear to mitigate the risk of SSI even in patients with prolonged surgical duration.

CONCLUSIONS

Increased surgical duration was an independent risk factor for SSI in orthopaedic patients undergoing endoprosthetic reconstruction after tumor resection. However, surgical duration is multifactorial and is influenced by several variables. For example, there may be protective features of flap coverage that increase surgical duration while paradoxically decreasing the risk of SSI. Extended postoperative antibiotic therapy did not mitigate the risk of infection in this cohort, and other risk mitigation strategies will need to be considered in future studies.

LEVEL OF EVIDENCE

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

Does the Use of Negative Pressure Wound Therapy and Postoperative Drains Impact the Development of Surgical Site Infections?: A PARITY Trial Secondary Analysis

BACKGROUND

Surgical site infections (SSIs) represent a major complication following oncologic reconstructions. Our objectives were (1) to assess whether the use of postoperative drains and/or negative pressure wound therapy (NPWT) were associated with SSIs following lower-extremity oncologic reconstruction and (2) to identify factors associated with the duration of postoperative drains and with the duration of NPWT.

METHODS

This is a secondary analysis of the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial, a multi-institution randomized controlled trial of lower-extremity oncologic reconstructions. Data were recorded regarding the use of drains alone, NPWT alone, or both NPWT and drains, including the total duration of each postoperatively. We analyzed postoperative drain duration and associations with tourniquet use, intraoperative thromboprophylaxis or antifibrinolytic use, incision length, resection length, and total operative time, through use of a linear regression model. A Cox proportional hazards model was used to evaluate the independent predictors of SSI.

RESULTS

Overall, 604 patients were included and the incidence of SSI was 15.9%. Postoperative drains alone were used in 409 patients (67.7%), NPWT alone was used in 15 patients (2.5%), and both postoperative drains and NPWT were used in 68 patients (11.3%). The median (and interquartile range [IQR]) duration of drains and of NPWT was 3 days (IQR, 2 to 5 days) and 6 days (IQR, 4 to 8 days), respectively. The use of postoperative drains alone, NPWT alone, or both drains and NPWT was not associated with SSI (p = 0.14). Increased postoperative drain duration was associated with longer operative times and no intraoperative tourniquet use, as shown on linear regression analysis (p < 0.001 and p = 0.03, respectively). A postoperative drain duration of ≥14 days (hazard ratio [HR], 3.6; 95% confidence interval [CI], 1.3 to 9.6; p = 0.01) and an operative time of ≥8 hours (HR, 4.5; 95% CI, 1.7 to 11.9; p = 0.002) were independent predictors of SSI following lower-extremity oncologic reconstruction.

CONCLUSIONS

A postoperative drain duration of ≥14 days and an operative time of ≥8 hours were independent predictors of SSI following lower-extremity oncologic reconstruction. Neither the use of postoperative drains nor the use of NPWT was a predictor of SSI. Future research is required to delineate the association of the combined use of postoperative drains and NPWT with SSI.

LEVEL OF EVIDENCE

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

Opioid Use in Surgical Management in Musculoskeletal Oncology

BACKGROUND

Opioid prescribing in the context of orthopaedic surgery has been recognized as having a critical role in the ongoing opioid epidemic. Given the negative consequences of chronic opioid use, great efforts have been made to reduce both preoperative and postoperative opioid prescribing and consumption in orthopaedic surgery. Musculoskeletal oncology patients represent a unique subset of patients, and there is a paucity of data evaluating perioperative opioid consumption and the risk for chronic use. The objective of the present study was to describe opioid consumption patterns and evaluate predictors of chronic opioid use in musculoskeletal oncology patients undergoing limb-salvage surgery and endoprosthetic reconstruction.

METHODS

The present study was a secondary analysis of the recently completed PARITY (Prophylactic Antibiotic Regimens in Tumor Surgery) trial and included musculoskeletal oncology patients undergoing lower-extremity endoprosthetic reconstruction. The primary outcome was the incidence of opioid consumption over the study period. A multivariate binomial logistic regression model was created to explore predictors of chronic opioid consumption at 1 year postoperatively.

RESULTS

Overall, 193 (33.6%) of 575 patients were consuming opioids preoperatively. Postoperatively, the number of patients consuming opioids was 82 (16.7%) of 492 at 3 months, 37 (8%) of 460 patients at 6 months, and 28 (6.6%) of 425 patients at 1 year. Of patients consuming opioids preoperatively, 12 (10.2%) of 118 had continued to consume opioids at 1 year postoperatively. The adjusted regression model found that only surgery for metastatic bone disease was predictive of chronic opioid use (odds ratio, 4.90; 95% confidence interval, 1.54 to 15.40; p = 0.007). Preoperative opioid consumption, older age, sex, longer surgical times, reoperation rates, and country of origin were not predictive of chronic use.

CONCLUSIONS

Despite a high prevalence of preoperative opioid use, an invasive surgical procedure, and a high rate of reoperation, few patients had continued to consume opioids at 1 year postoperatively. The presence of metastases was associated with chronic opioid use. These results are a substantial departure from the existing orthopaedic literature evaluating other patient populations, and they suggest that specific prescribing guidelines are warranted for musculoskeletal oncology patients.

LEVEL OF EVIDENCE

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

The Impact of Implant Fixation Type on Reoperation Rates Following Endoprosthetic Reconstruction Surgery

BACKGROUND

Prospective evidence supporting the use of cemented or uncemented implants in endoprosthetic reconstruction is lacking. The present study aimed to determine the effect of cemented fixation compared with uncemented fixation on the rate of all-cause reoperation at 1 year postoperatively.

METHODS

This is a secondary analysis of the Prophylactic Antibiotic Regimens In Tumor Surgery (PARITY) trial. A total of 503 patients who underwent surgical excision and endoprosthetic reconstruction of a lower-extremity bone tumor were included in this analysis. A multivariate Cox proportional hazards model was utilized to assess the independent relationship between fixation group and implant survivorship, with all-cause reoperation as the end point.

RESULTS

There were 388 cemented implants and 115 uncemented implants. Participants had a mean age of 42.7 years (standard deviation, 22.0 years), and 59% were male. Overall, 131 reoperations were identified over the 1-year follow-up period. There were no significant differences found in all-cause reoperation (hazard ratio [HR], 1.05; 95% confidence interval [CI], 0.70 to 1.57; p = 0.761), septic reoperation, or aseptic reoperation between cemented and uncemented fixation at 1 year postoperatively. The Cox regression analysis demonstrated that total operative time (HR per hour, 1.10; 95% CI, 1.02 to 1.20; p = 0.019) was an independent predictor of reoperation. The risk of reoperation was lower in patients with benign aggressive disease (HR, 0.11; 95% CI, 0.02 to 0.80; p = 0.029) or metastatic bone disease (HR, 0.30; 95% CI, 0.11 to 0.85; p = 0.023). Patients who underwent cemented fixation showed clinically meaningful functional improvement at 1 year postoperatively.

CONCLUSIONS

Cemented compared with uncemented fixation has no effect on 1-year all-cause reoperation rates in endoprosthetic reconstruction surgery. Further research is required to investigate the long-term survival of cemented versus uncemented implants.

LEVEL OF EVIDENCE

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

Risk Factors for All-Cause Early Reoperation Following Tumor Resection and Endoprosthetic Reconstruction: A Secondary Analysis from the PARITY Trial

BACKGROUND

Oncologic resection and endoprosthetic reconstruction of lower-extremity musculoskeletal tumors are complex procedures fraught with multiple modes of failure. A robust assessment of factors contributing to early reoperation in this population has not been performed in a large prospective cohort. The aim of the present study was to assess risk factors for early reoperation in patients who underwent tumor excision and endoprosthetic reconstruction, with use of data from the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial.

METHODS

Baseline characteristics were assessed, including age, sex, tumor type, tumor location, presence of a soft-tissue mass, diabetes, smoking status, chemotherapy use, and neutropenia. Operative factors were recorded, including operative time, topical antibiotics, silver-coated prosthetics, endoprosthetic fixation, extra-articular resection, length of bone resected, margins, tranexamic acid, postoperative antibiotics, negative-pressure wound therapy, and length of stay. Univariate analysis was utilized to explore the differences between patients who did and did not undergo reoperation within 1 year postoperatively, and a multivariate Cox proportional hazards regression model was utilized to explore the predictors of reoperation within 1 year.

RESULTS

A total of 155 (25.7%) of 604 patients underwent ≥1 reoperation. In univariate analysis, tumor type (p < 0.001), presence of a soft-tissue mass (p = 0.045), operative time (p < 0.001), use of negative-pressure wound therapy (p = 0.010), and hospital length of stay (p < 0.001) were all significantly associated with reoperation. On multivariate assessment, tumor type (benign aggressive bone tumor versus primary bone malignancy; hazard ratio [HR], 0.15; 95% confidence interval [CI], 0.04 to 0.63; p = 0.01), operative time (HR per hour, 1.15; 95% CI, 1.10 to 1.23; p < 0.001), and use of negative-pressure wound therapy (HR, 1.93; 95% CI, 1.30 to 2.90; p = 0.002) remained significant predictors of reoperation within 1 year.

CONCLUSIONS

Independent variables associated with reoperation within 1 year in patients who underwent tumor resection and endoprosthetic reconstruction included tumor type (benign aggressive bone tumor versus primary bone malignancy), operative time, and use of negative-pressure wound therapy. These results will help to inform patients and surgeons regarding the risk of reoperation by diagnosis and reinforce operative time as a factor influencing reoperation. These results also support further investigation into the use of negative-pressure wound therapy at the time of surgery in this patient population.

LEVEL OF EVIDENCE

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

Incidence of and Risk Factors for Thromboembolism After Endoprosthetic Reconstruction in Musculoskeletal Oncology Patients

BACKGROUND

The aim of the present study was to assess the incidence of and risk factors for thromboembolic events-including assessment of the intraoperative use of tranexamic acid and postoperative use of chemical thromboprophylaxis-in patients undergoing operative treatment of primary bone or soft-tissue sarcoma or oligometastatic bone disease.

METHODS

This study was performed as a secondary analysis of prospective data collected from the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) randomized controlled trial, which included 604 patients ≥12 years old who underwent surgical resection and endoprosthetic reconstruction for either primary bone or soft-tissue sarcoma or oligometastatic disease of the femur or tibia. We determined the incidence of thromboembolic events in these patients and evaluated potential risk factors, including patient age, sex, antibiotic treatment group, type of tumor (i.e., primary bone or soft-tissue sarcoma or metastatic bone disease), intraoperative tranexamic acid, tourniquet use, operative time, pathologic characteristics (i.e., American Joint Committee on Cancer grade, vascular invasion, and percent necrosis), postoperative chemical thromboprophylaxis regimen, and surgical site infection. Continuous variables were assessed with use of the Student t test. Categorical variables were assessed with use of the Pearson chi-square test, except when the expected cell counts were <5, in which case the Fisher exact test was utilized. Significance was set at 0.05.

RESULTS

Postoperative thromboembolic events occurred in 11 (1.8%) of 604 patients. Patients who experienced a thromboembolic event had a significantly higher mean (± standard deviation) age (59.6 ± 17.5 years) than those who did not experience a thromboembolic event (40.9 ± 21.8; p = 0.002). Patients randomized to the long-term antibiotic group had a significantly higher incidence of thromboembolic events (9 of 293; 3.1%) than those randomized to the short-term antibiotic group (2 of 311; 0.64%; p = 0.03). Neither intraoperative tranexamic acid nor postoperative chemical thromboprophylaxis were significantly associated with the occurrence of a thromboembolic event.

CONCLUSIONS

Although relatively rare in the PARITY cohort, thromboembolic events were more likely to occur in older patients and those receiving long-term prophylactic antibiotics. Intraoperative tranexamic acid and postoperative chemical thromboprophylaxis were not associated with a greater incidence of thromboembolic events.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Central Adjudication Committee and Clinical Site Investigator Agreement on Outcomes in the PARITY Trial: A Secondary Analysis of the PARITY Trial Data

BACKGROUND

The detection of a surgical site infection (SSI) in patients with metal implants requires a high degree of clinical acumen. The inherent subjectivity of SSI diagnosis poses a challenge in the design of surgical trials because this subjectivity raises concern for outcome assessment bias. Central Adjudication Committees (CACs) are often utilized to minimize the variability in outcome assessment. Little research has been done to determine the reliability of outcome assessment in trials utilizing a CAC. In the present study, we determined the agreement between the study CAC and the clinical site investigators for the primary and secondary outcome assessments.

METHODS

The Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial was a multicenter, blinded, parallel 2-arm, randomized controlled trial that aimed to determine the effect of a 5-day versus 1-day postoperative prophylactic antibiotic regimen on the rate of SSI in patients undergoing surgical excision of tumors in the femur or tibia. The blinded PARITY CAC adjudicated all primary and secondary outcomes identified during the 1-year study follow-up. In the present secondary analysis, the Cohen kappa statistic was utilized to determine the level of agreement.

RESULTS

The primary outcome of SSI diagnosis demonstrated a substantial level of agreement between the CAC and the site investigators (0.699; 95% confidence interval [CI], 0.595 to 0.803]). Categorization of the SSI (i.e., superficial, deep, or organ space) showed moderate agreement (0.470; 95% CI, 0.382 to 0.558). Secondary outcomes such as the types of reoperations and the indication for reoperation typically showed substantial to almost perfect agreement, whereas antibiotic-related complications showed fair agreement (0.241; 95% CI, 0.000 to 0.474).

CONCLUSIONS

Although there was a substantial level of agreement between the PARITY CAC and site investigators on the diagnosis of an SSI, as well as typically at least substantial agreement on the causes and types of reoperations, there was less agreement regarding the type of SSI and the occurrence of an antibiotic-related complication. Therefore, the CAC appears to have provided value when adjudicating the depth of infection and when determining the causality of medical complications associated with antibiotics.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Femoral Magnetic Lengthening After Distal Femur Endoprosthetic Reconstruction in a Pediatric Patient: A Case Report

CASE

A 10-year-old boy with osteosarcoma of the left distal femur underwent resection with compressive osseointegration endoprosthetic reconstruction, gradually resulting in a 4.5-cm leg-length difference with significant predicted progression. Two years after resection, he underwent right distal femur and proximal tibia epiphysiodesis and placement of a left femoral magnetic lengthening nail. At 2 years after lengthening and skeletal maturity, the patient has symmetric limb lengths, no pain, and returned to sports.

CONCLUSION

A magnetic lengthening nail with contralateral epiphysiodesis is a viable option for correcting limb-length discrepancy after distal femur endoprosthetic reconstruction in a pediatric patient.

In vitro and Ex vivo Assessments of the Compatibility of Fibrin Sealant with Antimicrobial Compounds

Background: Fibrin sealants are used as antimicrobial-releasing carriers for preventing surgical site infections; however, it is important to determine the release kinetics and antimicrobial effects of drugs added to fibrin sealants and the effects of drugs on clot/clotting properties. Materials and Methods: The antimicrobial and antibiofilm activity of cefazolin, colistin, gentamicin, oxacillin, tobramycin, and silver nitrate released from fibrin sealant were characterized using in vitro and ex vivo assays against bacteria commonly found on the skin. The effects of antimicrobial agents on the physical structure of the fibrin sealant were assessed with scanning electron microscopy (SEM) and on the clotting rate and strength of fibrin clots using run-off tests and rheology. Results: Generally, antibiotic agents were released gradually from fibrin sealant and were stable after release, with antimicrobial effects evident up to three days. Cefazolin, gentamicin, and oxacillin prevented biofilm formation of Staphylococcus aureus in porcine skin explants; gentamicin and colistin prevented biofilm formation of Pseudomonas aeruginosa. Gentamicin, cefazolin, colistin, and tobramycin did not affect the structural integrity or viscoelastic properties of fibrin sealant; changes were observed with oxacillin (SEM) and particularly silver nitrate (SEM and rheology). No antimicrobial agents caused deterioration of clotting time (run-off tests). Conclusions: From the antimicrobial agents tested, gentamicin and cefazolin showed prolonged release from fibrin sealant, sustained antimicrobial activity, and biofilm prevention properties against Staphylococcus aureus; similar results were observed for gentamicin and colistin against Pseudomonas aeruginosa. For each of these findings, the physical structure of the fibrin sealant, clotting rate, and strength of fibrin clots were unaffected.

Fixation Principles for Pathologic Fractures in Metasatic Disease

The management of pathologic fractures differs from nonpathologic fractures with respect to preoperative evaluation, surgical strategies, adjuvant therapies, and complication rates. These issues must be understood to provide appropriate musculoskeletal care for patients with metastatic disease.

Can the Future of ID Escape the Inertial Dogma of Its Past? The Exemplars of Shorter Is Better and Oral Is the New IV

Like all fields of medicine, Infectious Diseases is rife with dogma that underpins much clinical practice. In this study, we discuss 2 specific examples of historical practice that have been overturned recently by numerous prospective studies: traditional durations of antimicrobial therapy and the necessity of intravenous (IV)-only therapy for specific infectious syndromes. These dogmas are based on uncontrolled case series from >50 years ago, amplified by the opinions of eminent experts. In contrast, more than 120 modern, randomized controlled trials have established that shorter durations of therapy are equally effective for many infections. Furthermore, 21 concordant randomized controlled trials have demonstrated that oral antibiotic therapy is at least as effective as IV-only therapy for osteomyelitis, bacteremia, and endocarditis. Nevertheless, practitioners in many clinical settings remain refractory to adopting these changes. It is time for Infectious Diseases to move beyond its history of eminent opinion-based medicine and truly into the era of evidenced-based medicine.

Tourniquet use in patients undergoing tumour resection and endoprosthetic reconstruction of the knee

AIMS

The aim of this study was to determine the prevalence and impact of tourniquet use in patients undergoing limb salvage surgery with endoprosthetic reconstruction for a tumour around the knee.

METHODS

We retrieved data from the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial; specifically, differences in baseline characteristics, surgical details, and postoperative functional outcomes between patients who had undergone surgery under tourniquet and those who had not. A linear regression model was created to evaluate the impact of tourniquet use on postoperative Toronto Extremity Salvage Scores (TESSs) while controlling for confounding variables. A negative-binomial regression model was constructed to explore predictors of postoperative length of stay (LOS).

RESULTS

Of the 604 patients enrolled in the PARITY trial, 421 had tumours around the knee joint, of whom 225 (53%) underwent surgery under tourniquet. The tourniquet group was younger (p = 0.014), more likely to undergo surgery for a tumour of the tibia, and had shorter operating times by a mean of 50 minutes (95% confidence interval 30 to 72; p < 0.001). The adjusted linear regression model found that the use of a tourniquet, a shorter operating time, and a higher baseline TESS independently predicted better function at both three- and six-month follow-up. The negative-binomial regression model showed that tourniquet use, shorter operating time, younger age, and intraoperative tranexamic acid administration independently predicted a shorter LOS in hospital.

CONCLUSION

The results of this study show that in patients undergoing resection of a tumour around the knee and endoprosthetic reconstruction, the use of an intraoperative tourniquet is associated with a shorter operating time, a reduced length of stay in hospital, and a better early functional outcome.Cite this article: Bone Joint J 2022;104-B(10):1168-1173.

Antibiotic Prophylaxis for Megaprosthetic Reconstructions: Drug and Dosing May Matter More than Duration

In orthopedic oncology, the implant of a megaprosthetic device is standard of care after large-scale tumor resection involving segmental removal of bone. Infection remains the leading cause of implant failure, often resulting in major morbidity. Perioperative antibiotic practices for megaprosthetic reconstructions are not standardized and are based on guidelines for conventional joint arthroplasties. This study aims to evaluate the efficacy of current prophylactic strategies for megaprosthetic reconstructions. We conducted a retrospective review of megaprosthetic reconstructions performed at Duke University from 2001 to 2021. Logistic regression with GEE was used to assess whether a prolonged course of postoperative antibiotics is associated with infection risk. We assessed the microbial profile and corresponding susceptibilities of megaprosthetic infections through record review. Additionally, we designed a pharmacokinetic subgroup analysis using liquid chromatography-tandem mass spectrometry to quantify antibiotic concentrations in surgical tissue. Wilcoxon rank-sum tests were used to correlate tissue concentrations with infection risk. Out of 184 cases, 23 (12.5%) developed infection within 1 year. Extended postoperative antibiotics were not significantly associated with infection risk (P = 0.23). Among 18 culture-positive cases, 4 (22.2%) were caused by cefazolin-susceptible organisms. Median bone and muscle concentrations of cefazolin among cases that developed postoperative infection (0.065 ng/mL and 0.2 ng/mL, respectively) were significantly lower than those of cases that did not (0.42 ng/mL and 1.95 ng/mL, P < 0.01 and P = 0.03). This study is the first to comprehensively assess aspects of perioperative prophylaxis for megaprosthetic reconstructions. Extending postoperative antibiotics did not reduce infection risk. We detected a high frequency of cefazolin nonsusceptible organisms among postoperative infections. Additionally, intraoperative antibiotic tissue concentrations may be predictive of later infection. Future studies ought to examine optimal drug choices and dosing strategies.