Risk factors for surgical site infection after posterior fixation surgery and intraoperative radiotherapy for spinal metastases

The Perioperative Effects of Preoperative Radiotherapy in Metastatic Spinal Tumor Patients

OBJECTIVE

Radiotherapy is one of the important treatment options for metastatic spinal tumors but is not the definite intervention in all cases, as there are patients who still require surgical treatment because of severe pain or neurologic events after this treatment. We evaluated the perioperative effects of preoperative radiotherapy in these cases as a future guide for surgeons on critical considerations in this period.

METHODS

We included 328 patients in this study who had undergone decompression and fusion surgery for metastatic spinal tumors. Patients who underwent surgery with preoperative radiotherapy were designated as the radiotherapy group (group RT, n = 81), and cases of surgery without preoperative radiotherapy were assigned to the non-radiotherapy group (group nRT, n = 247). We compared the demographic, intraoperative, and postoperative factors between these 2 groups.

RESULTS

In terms of intraoperative factors, statistically significant differences were evident in operation time, estimated blood loss, and transfusion (RT vs. nRT: 188.1 ± 80.7 minutes vs. 231.2 ± 106.1 minutes, 607.2 ± 532.7 mL vs. 830.1 ± 1324.7 mL, and 30.9% vs. 43.3%, P < 0.001, P < 0.031, and P < 0.048, respectively). With regard to postoperative factors, the incidence of infection, wound problems, and local recurrence were statistically higher in group RT (RT vs. nRT: 6.2% vs. 0.8%, 12.3% vs. 0.8%, 23.4% vs. 13.7%, P = 0.004, P < 0.001, and P = 0.038, respectively).

CONCLUSIONS

Preoperative radiotherapy has the intraoperative advantages of reducing bleeding and shortening the operating time, but postoperative caution is needed because of the possibility of infection, wound problems, and local recurrence increases.

Intraoperative radiotherapy combined with spinal stabilization surgery-a novel treatment strategy for spinal metastases based on a first single-center experiences

INTRODUCTION

Current treatment of spinal metastases (SM) aims on preserving spinal stability, neurological status, and functional status as well as achieving local control. It consists of spinal surgery followed by radiotherapy and/or systemic treatment. Adjuvant therapy usually starts with a delay of a few weeks to prevent wound healing issues. Intraoperative radiotherapy (IORT) has previously been successfully applied during brain tumor, breast and colorectal carcinoma surgery but not in SM, including unstable one, to date. In our case series, we describe the feasibility, morbidity and mortality of a novel treatment protocol for SM combining stabilization surgery with IORT.

METHODS

Single center case series on patients with SM. Single session stabilization by navigated open or percutaneous procedure using a carbon screw-rod system followed by concurrent 50 kV photon-IORT (ZEISS Intrabeam). The IORT probe is placed via a guide canula using navigation, positioning is controlled by IOCT or 3D-fluroscopy enabling RT isodose planning in the OR.

RESULTS

15 (8 female) patients (71 ± 10y) received this treatment between 07/22 and 09/23. Median Spinal Neoplastic Instability Score was 8 [7-10] IQR. Most metastasis were located in the thoracic (n = 11, 73.3%) and the rest in the lumbar (n = 4, 26.7%) spine. 9 (60%) patients received open, 5 (33%) percutaneous stabilization and 1 (7%) decompression only. Mean length of surgery was 157 ± 45 min. Eleven patients had 8 and 3 had 4 screws placed. In 2 patients radiotherapy was not completed due to bending of the guide canula with consecutive abortion of IORT. All other patients received 8 Gy isodoses at mdn. 1.5 cm [1.1-1.9, IQR] depth during 2-6 min. The patients had Epidural Spinal Cord Compression score 1a-3. Seven patients (46.7%) experienced adverse events including 2 surgical site infection (one 65 days after surgery).

CONCLUSION

50 kV photon IORT for SM and consecutive unstable spine needing surgical intervention is safe and feasible and can be a promising technique in selected cases.

Risk factors for postoperative surgical site wound problems after metastatic and primary spine tumour surgery: A meta-analysis

A meta-analysis study was conducted to assess the risk factors (RFs) for postoperative surgical site wound problems (POSSWPs) after metastatic and primary spine tumour surgery (STS). A comprehensive literature examination until February 2023 was implemented, and 1786 linked studies were appraised. The 18 picked studies contained 18 580 subjects with surgery in the studies' baseline with and without different RFs. Odds ratio (OR) in addition to 95% confidence intervals (CIs) were used to calculate the consequence of RFs for POSSWPs after metastatic and primary STS using the dichotomous and continuous styles and a fixed or random model. Subjects with surgical instrumentation in their surgery had a significantly higher rate of POSSWPs in STS (OR, 2.28; 95% CI, 1.49-3.49, P < 0.001) compared with those without surgical instrumentation. Subjects with preoperative chemotherapy had a significantly higher rate of POSSWPs in STS (OR, 1.81; 95% CI, 1.09-3.00, P = 0.02) compared with those without preoperative chemotherapy. Subjects with preoperative radiotherapy had a significantly higher rate of POSSWPs in STS (OR, 1.93; 95% CI, 1.12-3.34, P = 0.02) compared with those without preoperative radiotherapy. Subjects with corticosteroid intake had a significantly higher rate of POSSWPs in STS (OR, 2.89; 95% CI, 1.73-4.82, P < 0.001) compared with those without corticosteroid intake. No significant difference was found between males and females in the rate of POSSWPs in STS (OR, 0.95; 95% CI, 0.66-1.37, P = 0.78). Surgical instrumentation, preoperative chemotherapy, preoperative radiotherapy and corticosteroid are RFs for the higher rate of POSSWPs in STS; however, gender was not shown to be a risk factor. Though precautions should be taken when commerce with the consequences since some of the studies picked for this meta-analysis had low sample sizes.

Infections of Tumor Prostheses: An Updated Review on Risk Factors, Microbiology, Diagnosis, and Treatment Strategies

Several causes contribute to the high infection rate in tumor prostheses, including extensive tissue dissection and patients' immunosuppression due to the neoplastic disease. Most of these infections develop within the first 2 years following surgery with 70% of them occurring during the first year, while they are often associated with a low pathogen burden. The pathogenesis of infections in tumor prostheses is linked to bacteria developing in biofilms. Approximately half of them are caused by Staphylococcus spp., followed by Streptococcus spp., Enterococcus spp., and Enterobacteriaceae spp., while multiple pathogens may be isolated in up to 25% of the cases, with coagulase-negative Staphylococci (CoNS) and Enterococccus spp. being the most frequent pair. Although early detection and timely management are essential for complete resolution of these challenging infections, prompt diagnosis is problematic due to the highly varying clinical symptoms and the lack of specific preoperative and intraoperative diagnostic tests. Surgical management with one- or two-stage revision surgery is the mainstay for successful eradication of these infections. The recent advances in laboratory diagnostics and the development of biofilm-resistant prostheses over the past years have been areas of great interest, as research is now focused on prevention strategies. The aim of this study is to review and consolidate the current knowledge regarding the epidemiology, risk factors, microbiology, and diagnosis of infections of tumor prostheses, and to review the current concepts for their treatment and outcomes.

Wound complications in metastatic spine tumor patients with and without preoperative radiation

OBJECTIVE

Wound complications are a common adverse event following metastatic spine tumor surgery. Some patients with spinal metastases may first undergo radiation but eventually require spinal surgery because of either cord compression or instability. The authors compared wound complication rates in patients who had undergone surgery for metastatic disease and received preoperative radiation treatments, postoperative radiation, or no radiation.

METHODS

Records from patients treated at the University of California, San Francisco, for metastatic spine disease between 2005 and 2017 were retrospectively reviewed. Baseline characteristics were collected, including preoperative Karnofsky Performance Status (KPS), Spine Instability Neoplastic Score, total radiation dose, indication for surgery, diabetes status, time between radiation and surgery, use of perioperative chemotherapy or steroids, estimated blood loss, extent of fusion, and preoperative albumin level. Wound complication was defined as poor healing, dehiscence, or infection per the Centers for Disease Control and Prevention guidelines, within 6 months of surgery. One-way ANOVA was used to compare means across groups. Cumulative incidence analysis with competing risk methodology was used to adjust for risk of death during follow-up. Statistical analysis was performed using R software.

RESULTS

Two hundred five patients with adequate medical records were identified. Seventy patients had received preoperative radiation, 74 had received postoperative radiation within 6 months after surgery, and 61 had received no radiation at the surgical site. Wound complication rates were similar across the 3 cohorts: 14.3% (n = 10) in the group with preoperative radiation, 10.8% (n = 8) in the group that received postoperative radiation, and 11.5% (n = 7) in the group with no radiation (p = 0.773). Competing risk analysis showed a higher cumulative incidence of wound complications for the preoperative cohort, though this difference was not significant (p = 0.46). Overall, 89 patients were treated with external beam radiation therapy (EBRT), whereas 55 received stereotactic body radiation therapy (SBRT). There was no significant difference in wound complications for patients treated with EBRT (11.2%, n = 10) versus SBRT (14.5%, n = 8; p = 0.825). KPS was the only factor correlated with wound complications on univariate analysis (p = 0.03).

CONCLUSIONS

Wound complication rates did not differ across the 3 cohorts: patients treated with preoperative radiation, postoperative radiation within 6 months of surgery, or no radiation. The effect size was small for KPS and likely does not represent a clinically significant predictor of wound complications.

Risk factors for surgical site infection in head and neck cancer

PURPOSE

Surgical site infection (SSI) frequently occurs in patients with head and neck cancer (HNC) after tumor resection and can lead to death in severe cases. Moreover, there is no definitive conclusion about the risk factors of SSI. Therefore, it is of great clinical significance to study the factors affecting the SSI.

METHODS

The HNC patients included in this study were all from the Department of Oral and Maxillofacial Surgery of the Second Xiangya Hospital of Central South University (CSU), and these patients received surgical treatment in the department from January 2018 to December 2019. The cross tabulation with chi-squared testing and multivariate regression analysis were applied to determine the risk factors of SSI. To identify the key risk factors of SSI, the caret package was used to construct three different machine learning models to investigate important features involving 26 SSI-related risk factors.

RESULTS

Participants were 632 HNC patients who underwent surgery in our department from January 2018 to December 2019. During the postoperative period, 82 patients suffered from SSI, and surgical site infection rate (SSIR) was about 12.97%. Multivariate logistic regression analysis shows that diabetes mellitus, primary tumor site (floor of mouth), preoperative radiotherapy, flap failure, and neck dissection (bilateral) are risk factors for SSI of HNC. Machine learning indicated that diabetes mellitus, primary tumor site (floor of mouth), and flap failure were consistently ranked the top three in the 26 SSI-related risk factors.

CONCLUSION

Diabetes mellitus, primary tumor site (floor of mouth), flap failure, preoperative radiotherapy, and neck dissection (bilateral) are risk factors for SSI of HNC.

Risk factors for deep surgical site infection following posterior instrumented fusion for degenerative diseases in the thoracic and/or lumbar spine: a multicenter, observational cohort study of 2913 consecutive cases

PURPOSE

Surgical site infection (SSI) is one of the most devastating complications following spinal instrumented fusion surgeries because it may lead to a significant increase in morbidity, mortality, and poor clinical outcomes. Identifying the risk factors for SSI can help in developing strategies to reduce its occurrence. However, data on the risk factors for SSI in degenerative diseases are limited. This study aimed to identify risk factors for deep SSI following posterior instrumented fusion for degenerative diseases in the thoracic and/or lumbar spine in adult patients.

METHODS

This was a multicenter, observational cohort study conducted at 10 study hospitals between July 2010 and June 2015. The subjects were consecutive adult patients who underwent posterior instrumented fusion surgery for degenerative diseases in the thoracic and/or lumbar spine and developed SSI. Detailed patient-specific and procedure-specific potential risk variables were prospectively recorded using a standardized data collection chart and retrospectively reviewed.

RESULTS

Of the 2913 enrolled patients, 35 developed postoperative deep SSI (1.2%). Multivariable regression analysis identified three independent risk factors: male sex (P = 0.002) and American Society of Anesthesiologists (ASA) score of ≥ 3 (P = 0.003) as patient-specific risk factors, and operation including the thoracic spine (P = 0.018) as a procedure-specific risk factor.

CONCLUSION

Thoracic spinal surgery, an ASA score of ≥ 3, and male sex were risk factors for deep SSI after routine thoracolumbar instrumented fusion surgeries for degenerative diseases. Awareness of these risk factors can enable surgeons to develop a more appropriate management plan and provide better patient counseling.

Risk Factors for Wound-Related Complications After Surgery for Primary and Metastatic Spine Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE

We systematically reviewed the literature to compare risk factors for postoperative complications at the surgical wound site in primary and metastatic tumor operations.

METHODS

We screened English-language publications on the outcomes of primary and metastatic spinal tumor operations. Pooled analyses and meta-analyses with random-effects modeling were performed comparing patients with and without wound complications, which were defined as surgical site infection or sterile wound dehiscence.

RESULTS

Our search identified 5471 unique citations, from which we included 23 studies describing 5104 patients. A total of 1936 patients underwent surgery for primary tumors, with a wound complication rate of 8.1%. Subgroup analysis of benign and malignant primary tumors yielded significantly different wound complication rates of 7.8% and 26.9%, respectively. The metastatic tumor cohort included 168 patients and a complication rate of 6.6%. In a pooled analysis of primary tumors, higher wound complication rates were associated with sacral operations and the use of instrumentation. In the metastatic tumor cohort, higher complication rates were associated with female sex, smoking history, preoperative chemotherapy, preoperative radiotherapy, corticosteroid use, and previous spine surgery. Instrumentation remained a statistically significant risk factor for primary tumors with the addition of random-effects meta-analysis.

CONCLUSIONS

Risk factors for wound complications after primary tumor operations were related to tumor histology and the spinal location of the operation. Risk factors for metastatic tumors may be related to several systemic preoperative treatments and baseline comorbidities. Random-effects meta-analysis showed the limited generalizability of these findings because of the small heterogenous primary literature.

Reducing Surgical Site Infections in Spine Tumor Surgery: A Comparison of Three Methods

STUDY DESIGN

Case control series.

OBJECTIVE

The aim of this study was to evaluate and compare the effectiveness of methods to decrease surgical site infections (SSIs) following spine tumor surgery.

SUMMARY OF BACKGROUND DATA

With the aging population of the United States, the prevalence of cancer and associated metastatic spine disease is increasing. The most common complication of spine tumor surgery is SSI.

METHODS

This a single-institution case-control series of patients undergoing spine tumor surgery from June 2003 to October 2018. Patients were grouped into the following groups: Betadine irrigation and intrawound vancomycin powder (BIVP), intrawound vancomycin powder only (IVP), and patients receiving neither (NONE). The primary outcome was SSIs/wound complications.

RESULTS

One hundred fifty-one spine tumor patients undergoing 174 procedures meeting our inclusion criteria were identified. The BIVP group had 60 patients (73 procedures); the IVP group had 46 patients (47 procedures); and the NONE group had 45 patients (54 procedures). The overall infection rate was 8.6% of all procedures (15/174) and 9.9% (15/151) of all patients. Bivariate analysis comparing patients with and without infections noted the patients with SSIs had significantly higher rates of preoperative radiation treatment (53.3% in infection group vs. 25.5% in noninfection group), P = 0.02. Patients undergoing procedures in the BIVP group had a significantly lower rate of infections (2.7%) than the patients in the IVP (12.8%) and NONE (13%) groups, P = 0.04. Stepwise regression analysis was used to evaluate further factors associated with SSIs. Elevated BMI was significantly associated with SSIs in the model [P = 0.02, odds ratio (OR) 1.14]. BIVP was also protective against infections as compared to the IVP and NONE groups, P = 0.02, OR 0.02.

CONCLUSION

BIVP led to a significant decrease in SSI rates following spine tumor surgery. Administration of BIVP is not time consuming and decreased SSI rates.

LEVEL OF EVIDENCE

3.

Antimicrobial Prophylaxis for the Prevention of Surgical Site Infections in Orthopaedic Oncology - A Narrative Review of Current Concepts

The incidence of surgical site infections (SSIs) after elective tumour orthopaedic surgery in adults is higher than non-oncologic orthopaedic surgery. Their causative microorganisms and antibiotic susceptibilities are also different from the non-oncologic cases; with no apparent predictable microbiological patterns. Clinicians continue to struggle to tailor the optimal prophylactic regimen for the very heterogeneous group of tumour patients. Many clinicians thus prolong the first-and second-generation cephalosporin agents, while a minority chooses to broaden the antimicrobial spectrum by combination prophylaxis. The variability in current practices and surgical techniques is enormous, even within the same setting. The scientific literature lacks adequate retrospective case-studies and there is currently only one prospective randomized trial. In this narrative review, we discuss various perioperative antibiotic concepts in oncologic orthopaedic surgery, including a summary of the state-to-the-art, opinions and difficulties related to the different prophylactic strategies.

Surgical Site Infection in Spine Surgery: Who Is at Risk?

STUDY DESIGN

Retrospective literature review of spine surgical site infection (SSI).

OBJECTIVE

To perform a review of SSI risk factors and more specifically, categorize them into patient and surgical factors.

METHODS

A review of published literature on SSI risk factors in adult spine surgery was performed. We included studies that reported risk factors for SSI in adult spinal surgery. Excluded are pediatric patient populations, systematic reviews, and meta-analyses. Overall, we identified 72 cohort studies, 1 controlled-cohort study, 1 matched-cohort study, 1 matched-paired cohort study, 12 case-controlled studies (CCS), 6 case series, and 1 cross-sectional study.

RESULTS

Patient-associated risk factors-diabetes mellitus, obesity (body mass index >35 kg/m²), subcutaneous fat thickness, multiple medical comorbidities, current smoker, and malnutrition were associated with SSI. Surgical associated factors-preoperative radiation/postoperative blood transfusion, combined anterior/posterior approach, surgical invasiveness, or levels of instrumentation were associated with increased SSI. There is mixed evidence of age, duration of surgery, surgical team, intraoperative blood loss, dural tear, and urinary tract infection/urinary catheter in association with SSI.

CONCLUSION

SSIs are associated with many risk factors that can be patient or surgically related. Our review was able to identify important modifiable and nonmodifiable risk factors that can be essential in surgical planning and discussion with patients.

The role of the mini-open thoracoscopic-assisted approach in the management of metastatic spine disease at the thoracolumbar junction

Objective

Treatment advances have resulted in improved survival for many cancer types, and this, in turn, has led to an increased incidence of metastatic disease, specifically to the vertebral column. Surgical decompression and stabilization prior to radiation therapy have been shown to improve functional outcomes, but anterior access to the thoracolumbar junction may involve open thoracotomy, which can cause significant morbidity. The authors describe the treatment of 12 patients in whom a mini-open thoracoscopic-assisted approach (mini-open TAA) to the thoracolumbar junction was used to treat metastatic disease, with an analysis of outcomes.

Methods

The authors reviewed a retrospective cohort of patients treated for thoracolumbar junction metastatic disease with mini-open TAA between 2004 and 2016. Data collection included operative time, estimated blood loss, length of stay, follow-up duration, and pre- and postoperative visual analog scale scores and Frankel grades.

Results

Twelve patients underwent a mini-open TAA procedure for metastatic disease at the thoracolumbar junction. The mean age of patients was 59 years (range 53-77 years), mean estimated blood loss was 613 ml, and the mean duration of the mini-open TAA procedure was 234 minutes (3.8 hours). The median length of stay in the hospital was 7.5 days (range 5-21 days). All 12 patients had significant improvement in their postoperative pain scores in comparison with their preoperative pain scores (p < 0.001). No patients suffered from worsening neurological function after surgery, and of 7 patients who presented with neurological dysfunction, 6 (86%) had an improvement in their Frankel grade after surgery. No patients experienced delayed hardware failure requiring reoperation over a mean follow-up of 10 months (range 1-45 months).

Conclusions

The mini-open TAA to the thoracolumbar junction for metastatic disease is a durable procedure that has a reduced morbidity rate compared with traditional open thoracotomy for ventral decompression and fusion. It compares well with traditional and novel posterior approaches to the thoracolumbar junction. The authors found a significant improvement in preoperative pain and neurological symptoms that supports greater use of the mini-open TAA for the treatment of complex metastatic disease at the thoracolumbar junction.

Changing the Adverse Event Profile in Metastatic Spine Surgery: An Evidence-Based Approach to Target Wound Complications and Instrumentation Failure

STUDY DESIGN

Systematic review.

OBJECTIVE

To identify risk factors and preventive methods for wound complications and instrumentation failure after metastatic spine surgery.

SUMMARY OF BACKGROUND DATA

We focused on two postoperative complications of metastatic spine tumor surgery: wound complications and instrumentation failure and preventive measures.

METHODS

We performed a systematic review of the literature from 1980 to 2015. The articles were analyzed for the presence of documented infection and/or wound complications and instrumentation failure.

RESULTS

Forty articles met our inclusion criteria for wound complications and prevention. There is very low level of evidence that preoperative radiation, preoperative neurological deficit, revision procedures, and posterior approaches can contribute to wound complications (infections, wound dehiscence). There is very low level of evidence that plastic surgery soft tissue reconstruction, intrawound vancomycin powder, and percutaneous pedicle screws may prevent postoperative wound complications. Fourteen articles met our inclusion criteria for instrumentation failure. There is very low level of evidence that constructs greater than six levels, positive sagittal balance, preoperative radiation, and history of chest wall resection can contribute to implant failures.

CONCLUSION

• For patients undergoing revision metastatic spine tumor surgery, plastic surgery should perform the soft tissue reconstruction (strong recommendation/very low quality of evidence).• For patients undergoing metastatic spine tumor surgery, plastic surgery may perform immediate soft tissue reconstruction (weak recommendation/very low quality of evidence).• For patients undergoing metastatic spine tumor surgery, intrawound vancomycin can be applied to decrease the risk of postoperative wound infections (weak recommendation/very low quality of evidence).• For patients undergoing metastatic spine tumor surgery, percutaneous pedicle screws can be placed to decrease the risk of postoperative wound complications (weak recommendation/very low quality of evidence).• Instrumentation failure risk factors include constructs greater than six levels, positive sagittal balance, preoperative radiation, and history of chest wall resections (weak recommendation/very low quality of evidence).

LEVEL OF EVIDENCE

N/A.