Novel Standalone Motion-Sparing Pelvic Fixation Prevents Short-Term Insufficiency Fractures After Midsacrectomies Without Sacrificing Normal, Mobile Lumbar Segments Traditionally Used for Stabilization.

BACKGROUND AND OBJECTIVES: Sacrectomy is often the treatment of choice to provide the greatest chance of progression-free and overall survival for patients with primary malignant bone tumors of the sacrum. After midsacrectomy, the stability of the sacropelvic interface is diminished, resulting in insufficiency fractures. Traditional stabilization involves lumbopelvic fixation but subjects normal mobile segments to fusion. The purpose of this study was to determine whether standalone intrapelvic fixation is a safe adjunct to midsacrectomy, avoiding both sacral insufficiency fractures and the morbidity of instrumenting into the mobile spine. METHODS: A retrospective study identified all patients who underwent resection of sacral tumors at 2 comprehensive cancer centers between June 2020 and July 2022. Demographic, tumor-specific, operative characteristics and outcome data were collected. The primary outcome was presence of sacral insufficiency fractures. A retrospective data set of patients undergoing midsacrectomy without hardware placement was collected as a control. RESULTS: Nine patients (5 male, 4 female), median age 59 years, underwent midsacrectomy with concomitant placement of standalone pelvic fixation. No patients developed insufficiency fractures during the 216 days of clinical and 207 days of radiographic follow-up. There were no adverse events attributable to the addition of standalone pelvic fixation. In our historical cohort of partial sacrectomies without stabilization, there were 4/25 patients (16%) with sacral insufficiency fractures. These fractures appeared between 0 and 5 months postoperatively. CONCLUSION: A novel standalone intrapelvic fixation after partial sacrectomy is a safe adjunct to prevent postoperative sacral insufficiency fractures in patients undergoing midsacrectomy for tumor. Such a technique may allow for long-term sacropelvic stability without sacrificing mobile lumbar segments.

Creation and preclinical evaluation of a novel mussel-inspired, biomimetic, bioactive bone graft scaffold: direct comparison with Infuse bone graft using a rat model of spinal fusion.

OBJECTIVE: Infuse bone graft is a widely used osteoinductive adjuvant; however, the simple collagen sponge scaffold used in the implant has minimal inherent osteoinductive properties and poorly controls the delivery of the adsorbed recombinant human bone morphogenetic protein-2 (rhBMP-2). In this study, the authors sought to create a novel bone graft substitute material that overcomes the limitations of Infuse and compare the ability of this material with that of Infuse to facilitate union following spine surgery in a clinically translatable rat model of spinal fusion. METHODS: The authors created a polydopamine (PDA)-infused, porous, homogeneously dispersed solid mixture of extracellular matrix and calcium phosphates (BioMim-PDA) and then compared the efficacy of this material directly with Infuse in the setting of different concentrations of rhBMP-2 using a rat model of spinal fusion. Sixty male Sprague Dawley rats were randomly assigned to each of six equal groups: 1) collagen + 0.2 µg rhBMP-2/side, 2) BioMim-PDA + 0.2 µg rhBMP-2/side, 3) collagen + 2.0 µg rhBMP-2/side, 4) BioMim-PDA + 2.0 µg rhBMP-2/side, 5) collagen + 20 µg rhBMP-2/side, and 6) BioMim-PDA + 20 µg rhBMP-2/side. All animals underwent posterolateral intertransverse process fusion at L4-5 using the assigned bone graft. Animals were euthanized 8 weeks postoperatively, and their lumbar spines were analyzed via microcomputed tomography (µCT) and histology. Spinal fusion was defined as continuous bridging bone bilaterally across the fusion site evaluated via µCT. RESULTS: The fusion rate was 100% in all groups except group 1 (70%) and group 4 (90%). Use of BioMim-PDA with 0.2 µg rhBMP-2 led to significantly greater results for bone volume (BV), percentage BV, and trabecular number, as well as significantly smaller trabecular separation, compared with the use of the collagen sponge with 2.0 µg rhBMP-2. The same results were observed when the use of BioMim-PDA with 2.0 µg rhBMP-2 was compared with the use of the collagen sponge with 20 µg rhBMP-2. CONCLUSIONS: Implantation of rhBMP-2-adsorbed BioMim-PDA scaffolds resulted in BV and bone quality superior to that afforded by treatment with rhBMP-2 concentrations 10-fold higher implanted on a conventional collagen sponge. Using BioMim-PDA (vs a collagen sponge) for rhBMP-2 delivery could significantly lower the amount of rhBMP-2 required for successful bone grafting clinically, improving device safety and decreasing costs.

Predictors of survival and time to progression following operative management of intramedullary spinal cord astrocytomas.

PURPOSE: Surgical resection is considered standard of care for primary intramedullary astrocytomas, but the infiltrative nature of these lesions often precludes complete resection without causing new post-operative neurologic deficits. Radiotherapy and chemotherapy serve as potential adjuvants, but high-quality data evaluating their efficacy are limited. Here we analyze the experience at a single comprehensive cancer center to identify independent predictors of postoperative overall and progression-free survival. METHODS: Data was collected on patient demographics, tumor characteristics, pre-operative presentation, resection extent, long-term survival, and tumor progression/recurrence. Kaplan-Meier curves modeled overall and progression-free survival. Univariable and multivariable accelerated failure time regressions were used to compute time ratios (TR) to determine predictors of survival. RESULTS: 94 patients were included, of which 58 (62%) were alive at last follow-up. On multivariable analysis, older age (TR = 0.98; p = 0.03), higher tumor grade (TR = 0.12; p < 0.01), preoperative back pain (TR = 0.45; p < 0.01), biopsy [vs GTR] (TR = 0.18; p = 0.02), and chemotherapy (TR = 0.34; p = 0.02) were significantly associated with poorer survival. Higher tumor grade (TR = 0.34; p = 0.02) and preoperative bowel dysfunction (TR = 0.31; p = 0.02) were significant predictors of shorter time to detection of tumor growth. CONCLUSION: Tumor grade and chemotherapy were associated with poorer survival and progression-free survival. Chemotherapy regimens were highly heterogeneous, and randomized trials are needed to determine if any optimal regimens exist. Additionally, GTR was associated with improved survival, and patients should be counseled about the benefits and risks of resection extent.

A novel online calculator to predict nonroutine discharge, length of stay, readmission, and reoperation in patients undergoing surgery for intramedullary spinal cord tumors.

BACKGROUND CONTEXT: Intramedullary spinal cord tumors (IMSCTs) are rare tumors associated with significant morbidity and mortality. Surgical resection is often indicated for symptomatic lesions but may result in new neurological deficits and decrease quality of life. Identifying predictors of these adverse outcomes may help target interventions designed to reduce their occurrence. Nonetheless, most prior studies have employed population-level datasets with limited granularity. PURPOSE: To determine independent predictors of nonroutine discharge, prolonged length of stay (LOS), and 30 day readmission and reoperation, and to deploy these results as a web-based calculator. STUDY DESIGN: Retrospective cohort study PATIENT SAMPLE: A total of 235 patients who underwent resection of IMSCTs at a single comprehensive cancer center. OUTCOME MEASURES: Nonroutine discharge, prolonged LOS, 30 day readmission, and 30 day reoperation METHODS: Patients who underwent surgery from June 2002 to May 2020 at a single tertiary center were included. Data was collected on patient demographics, clinical presentation, tumor histology, surgical procedures, and 30 day readmission and reoperation. Functional status was assessed using the Modified McCormick Scale (MMS) and queried preoperative neurological symptoms included weakness, urinary and bowel dysfunction, numbness, and back and radicular pain. Variables significant on univariable analysis at the α≤0.15 level were entered into a stepwise multivariable logistic regression model. RESULTS: Of 235 included cases, 131 (56%) experienced a nonhome discharge and 68 (29%) experienced a prolonged LOS. Of 178 patients with ≥ 30 days of follow-up, 17 (9.6%) were readmitted within 30 days and 13 (7.4%) underwent reoperation. Wound dehiscence (29%) was the most common reason for readmission. Nonhome discharge was independently predicted by older age (OR=1.03/year; p<.01), thoracic location of the tumor (OR=2.36; p=.01), presenting with bowel dysfunction (OR=4.09; p=.03), and longer incision length (OR=1.44 per level; p=.03). Independent predictors of prolonged LOS included presenting with urinary incontinence (OR=2.65; p=.05) or a higher preoperative white blood cell count (OR=1.08 per 103/µL); p=.01), while GTR predicted shorter LOS (OR=0.40; p=.02). Independent predictive factors for 30 day unplanned readmission included experiencing ≥1 complications during the first hospitalization (OR=6.13; p<.01) and having a poor (A-C) versus good (D-E) baseline neurological status on the ASIA impairment scale (OR=0.23; p=.03). The only independent predictor of unplanned 30 day reoperation was experiencing ≥1 inpatient complications during the index hospitalization (OR=6.92; p<.01). Receiver operating curves for the constructed models produced C-statistics of 0.67-0.77 and the models were deployed as freely available web-based calculators (https://jhuspine5.shinyapps.io/Intramedullary30day). CONCLUSIONS: We found that neurological presentation, patient demographics, and incision length were important predictors of adverse perioperative outcomes in patients with IMSCTs. The calculators can be used by clinicians for risk stratification, preoperative counseling, and targeted interventions.

Perioperative outcomes and survival after surgery for intramedullary spinal cord tumors: a single-institution series of 302 patients.

OBJECTIVE: Intramedullary spinal cord tumors (IMSCTs) are rare neoplasms whose treatment is often technically challenging. Given the low volume seen at most centers, perioperative outcomes have been reported infrequently. Here, the authors present the largest single-institution series of IMSCTs, focusing on the clinical presentation, histological makeup, perioperative outcomes, and long-term survival of surgically treated patients. METHODS: A cohort of patients operated on for primary IMSCTs at a comprehensive cancer center between June 2002 and May 2020 was retrospectively identified. Data on patient demographics, tumor histology, neuraxial location, baseline neurological status, functional deficits, and operative characteristics were collected. Perioperative outcomes of interest included length of stay, postoperative complications, readmission, reoperation, and discharge disposition. Data were compared across tumor histologies using the Kruskal-Wallis H test, chi-square test, and Fisher exact test. Pairwise comparisons were conducted using Tukey's honest significant difference test, chi-square test, and Fisher exact test. Long-term survival was assessed across tumor categories and histological subtype using the log-rank test. RESULTS: Three hundred two patients were included in the study (mean age 34.9 ± 19 years, 77% white, 57% male). The most common tumors were ependymomas (47%), astrocytomas (31%), and hemangioblastomas (11%). Ependymomas and hemangioblastomas disproportionately localized to the cervical cord (54% and 59%, respectively), whereas astrocytomas were distributed almost equally between the cervical cord (36%) and thoracic cord (38%). Clinical presentation, extent of functional dependence, and postoperative 30-day outcomes were largely independent of underlying tumor pathology, although tumors of the thoracic cord had worse American Spinal Injury Association (ASIA) grades than cervical tumors. Rates of gross-total resection were lower for astrocytomas than for ependymomas (54% vs 84%, p < 0.01) and hemangioblastomas (54% vs 100%, p < 0.01). Additionally, 30-day readmission rates were significantly higher for astrocytomas than ependymomas (14% vs 6%, p = 0.02). Overall survival was significantly affected by the underlying pathology, with astrocytomas having poorer associated prognoses (40% at 15 years) than ependymomas (81%) and hemangioblastomas (66%; p < 0.01) and patients with high-grade ependymomas and astrocytomas having poorer long-term survival than those with low-grade lesions (p < 0.01). CONCLUSIONS: The neuraxial location of IMSCTs, extent of resection, and postoperative survival differed significantly across tumor pathologies. However, perioperative outcomes did not vary significantly across tumor cohorts, suggesting that operative details, rather than pathology, may have a stronger influence on the short-term clinical course, whereas pathology appears to have a stronger impact on long-term survival.

Utility of expanded anterior column resection versus decompression-alone for local control in the management of carcinomatous vertebral column metastases undergoing adjuvant stereotactic radiotherapy.

BACKGROUND CONTEXT: With improvements in adjuvant radiotherapy and minimally invasive surgical techniques, separation surgery has become the default surgical intervention for spine metastases at many centers. However, it is unclear if there is clinical benefit from anterior column resection in addition to simple epidural debulking prior to stereotactic body radiotherapy (SBRT). PURPOSE: To examine the effect of anterior column debulking versus epidural disease resection alone in the local control of metastases to the bony spine. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Ninety-seven patients who underwent open surgery followed by SBRT for spinal metastases at a single comprehensive cancer center. OUTCOME MEASURES: Local tumor recurrence following surgery and SBRT. METHODS: Data were collected regarding radiation dose, cancer histology, extent of anterior column resection, and recurrence. Tumor involvement was categorized using the International Spine Radiosurgery Consortium guidelines. Univariable analyses were conducted to determine predictors of local recurrence and time to local recurrence. RESULTS: Among the 97 included patients, mean age was 60.5±11.4 years and 51% of patients were male. The most common primary tumor types were lung (20.6%), breast (17.5%), kidney (13.4%) and prostate (12.4%). Recurrence was seen in 17 patients (17.5%) and local control rates were: 85.5% (1-year), 81.1% (2-year), and 54.9% (5-year). Overall predictors of local recurrence were tumor pathology (p<.01; renal cell carcinoma and colorectal adenocarcinoma associated with poorest PFS) and undergoing anterior column debulking versus epidural decompression-alone (p=.03). Only tumor pathology predicted time to local recurrence (p<.01), though inspection of Kaplan-Meier functions showed superior long-term local control in patients with radiosensitive tumor pathologies, no previous irradiation of the metastasis, and who underwent anterior column resection versus epidural removal alone. Median time to recurrence was 288 days with 100% of lesions showing anterior column recurrence and recurrence in the epidural space. CONCLUSIONS: With the increasing shift towards surgery as a neoadjuvant to radiotherapy for patients with spinal column metastases, the role for surgical debulking has become less clear. In the present study, we find that anterior column debulking as opposed to epidural debulking-alone decreases the odds of local recurrence and improves long-term local control.

Impact of race on nonroutine discharge, length of stay, and postoperative complications after surgery for spinal metastases.

OBJECTIVE: Previous studies have suggested the possibility of racial disparities in surgical outcomes for patients undergoing spine surgery, although this has not been thoroughly investigated in those with spinal metastases. Given the increasing prevalence of spinal metastases requiring intervention, knowledge about potential discrepancies in outcomes would benefit overall patient care. The objective in the present study was to investigate whether race was an independent predictor of postoperative complications, nonroutine discharge, and prolonged length of stay (LOS) after surgery for spinal metastasis. METHODS: The authors retrospectively examined patients at a single comprehensive cancer center who had undergone surgery for spinal metastasis between April 2013 and April 2020. Demographic information, primary pathology, preoperative clinical characteristics, and operative outcomes were collected. Factors achieving p values < 0.15 on univariate regression were entered into a stepwise multivariable logistic regression to generate predictive models. Nonroutine discharge was defined as a nonhome discharge destination and prolonged LOS was defined as LOS greater than the 75th percentile for the entire cohort. RESULTS: Three hundred twenty-eight patients who had undergone 348 operations were included: 240 (69.0%) White and 108 (31.0%) Black. On univariable analysis, cohorts significantly differed in age (p = 0.02), marital status (p < 0.001), insurance status (p = 0.03), income quartile (p = 0.02), primary tumor type (p = 0.04), and preoperative Karnofsky Performance Scale (KPS) score (p < 0.001). On multivariable analysis, race was an independent predictor for nonroutine discharge: Black patients had significantly higher odds of nonroutine discharge than White patients (adjusted odds ratio [AOR] 2.24, 95% confidence interval [CI] 1.28-3.92, p = 0.005). Older age (AOR 1.06 per year, 95% CI 1.03-1.09, p < 0.001), preoperative KPS score ≤ 70 (AOR 3.30, 95% CI 1.93-5.65, p < 0.001), preoperative Frankel grade A-C (AOR 3.48, 95% CI 1.17-10.3, p = 0.02), insurance status (p = 0.005), being unmarried (AOR 0.58, 95% CI 0.35-0.97, p = 0.04), number of levels (AOR 1.17 per level, 95% CI 1.05-1.31, p = 0.004), and thoracic involvement (AOR 1.71, 95% CI 1.02-2.88, p = 0.04) were also predictive of nonroutine discharge. However, race was not independently predictive of postoperative complications or prolonged LOS. Higher Charlson Comorbidity Index (AOR 1.22 per point, 95% CI 1.04-1.43, p = 0.01), low preoperative KPS score (AOR 1.84, 95% CI 1.16-2.92, p = 0.01), and number of levels (AOR 1.15 per level, 95% CI 1.05-1.27, p = 0.004) were predictive of complications, while insurance status (p = 0.05), income quartile (p = 0.01), low preoperative KPS score (AOR 1.64, 95% CI 1.03-2.72, p = 0.05), and number of levels (AOR 1.16 per level, 95% CI 1.05-1.30, p = 0.004) were predictive of prolonged LOS. CONCLUSIONS: Race, insurance status, age, baseline functional status, and marital status were all independently associated with nonroutine discharge. This suggests that a combination of socioeconomic factors and functional status, rather than medical comorbidities, may best predict postdischarge disposition in patients treated for spinal metastases. Further investigation in a prospective cohort is merited.

Comparison of frailty metrics and the Charlson Comorbidity Index for predicting adverse outcomes in patients undergoing surgery for spine metastases.

OBJECTIVE: Frailty-the state defined by decreased physiological reserve and increased vulnerability to physiological stress-is exceedingly common in oncology patients. Given the palliative nature of spine metastasis surgery, it is imperative that patients be healthy enough to tolerate the physical insult of surgery. In the present study, the authors compared the association of two frailty metrics and the widely used Charlson Comorbidity Index (CCI) with postoperative morbidity in spine metastasis patients. METHODS: A retrospective cohort of patients who underwent operations for spinal metastases at a comprehensive cancer center were identified. Data on patient demographic characteristics, disease state, medical comorbidities, operative details, and postoperative outcomes were collected. Frailty was measured with the modified 5-item frailty index (mFI-5) and metastatic spinal tumor frailty index (MSTFI). Outcomes of interest were length of stay (LOS) greater than the 75th percentile of the cohort, nonroutine discharge, and the occurrence of ≥ 1 postoperative complication. RESULTS: In total, 322 patients were included (mean age 59.5 ± 12 years; 56.9% of patients were male). The mean ± SD LOS was 11.2 ± 9.9 days, 44.5% of patients had nonroutine discharge, and 24.0% experienced ≥ 1 postoperative complication. On multivariable analysis, increased frailty on mFI-5 and MSTFI was independently predictive of all three outcomes: prolonged LOS (OR 1.67 per point, 95% CI 1.06-2.63, p = 0.03; and OR 1.63 per point, 95% CI 1.29-2.05, p < 0.01, respectively), nonroutine discharge (OR 2.65 per point, 95% CI 1.74-4.04, p < 0.01; and OR 1.69 per point, 95% CI 1.36-2.11, p < 0.01), and ≥ 1 complication (OR 1.95 per point, 95% CI 1.23-3.09, p = 0.01; and OR 1.41 per point, 95% CI 1.12-1.77, p < 0.01). CCI was found to be independently predictive of only the occurrence of ≥ 1 postoperative complication (OR 1.45 per point, 95% CI 1.22-1.72, p < 0.01). CONCLUSIONS: Frailty measured with either mFI-5 or MSTFI scores was a more robust independent predictor of adverse postoperative outcomes than the more widely used CCI. Both mFI-5 and MSTFI were significantly associated with prolonged LOS, higher complication rates, and nonroutine discharge. Further investigation in a prospective multicenter cohort is merited.

Influence of tranexamic acid use on venous thromboembolism risk in patients undergoing surgery for spine tumors.

OBJECTIVE: Patients with spine tumors are at increased risk for both hemorrhage and venous thromboembolism (VTE). Tranexamic acid (TXA) has been advanced as a potential intervention to reduce intraoperative blood loss in this surgical population, but many fear it is associated with increased VTE risk due to the hypercoagulability noted in malignancy. In this study, the authors aimed to 1) develop a clinical calculator for postoperative VTE risk in the population with spine tumors, and 2) investigate the association of intraoperative TXA use and postoperative VTE. METHODS: A retrospective data set from a comprehensive cancer center was reviewed for adult patients treated for vertebral column tumors. Data were collected on surgery performed, patient demographics and medical comorbidities, VTE prophylaxis measures, and TXA use. TXA use was classified as high-dose (≥ 20 mg/kg) or low-dose (< 20 mg/kg). The primary study outcome was VTE occurrence prior to discharge. Secondary outcomes were deep venous thrombosis (DVT) or pulmonary embolism (PE). Multivariable logistic regression was used to identify independent risk factors for VTE and the resultant model was deployed as a web-based calculator. RESULTS: Three hundred fifty patients were included. The mean patient age was 57 years, 53% of patients were male, and 67% of surgeries were performed for spinal metastases. TXA use was not associated with increased VTE (14.3% vs 10.1%, p = 0.37). After multivariable analysis, VTE was independently predicted by lower serum albumin (odds ratio [OR] 0.42 per g/dl, 95% confidence interval [CI] 0.23-0.79, p = 0.007), larger mean corpuscular volume (OR 0.91 per fl, 95% CI 0.84-0.99, p = 0.035), and history of prior VTE (OR 2.60, 95% CI 1.53-4.40, p < 0.001). Longer surgery duration approached significance and was included in the final model. Although TXA was not independently associated with the primary outcome of VTE, high-dose TXA use was associated with increased odds of both DVT and PE. The VTE model showed a fair fit of the data with an area under the curve of 0.77. CONCLUSIONS: In the present cohort of patients treated for vertebral column tumors, TXA was not associated with increased VTE risk, although high-dose TXA (≥ 20 mg/kg) was associated with increased odds of DVT or PE. Additionally, the web-based clinical calculator of VTE risk presented here may prove useful in counseling patients preoperatively about their individualized VTE risk.

Drivers of Readmission and Reoperation After Surgery for Vertebral Column Metastases.

OBJECTIVE: To determine those clinical, demographic, and operative factors that predict 30-day unplanned reoperation and readmission within a population of adults who underwent spinal metastasis surgery at a comprehensive cancer center. METHODS: Adults who underwent spinal metastasis surgery at a comprehensive cancer center were analyzed. Data included baseline laboratory values, cancer history, demographics, operative characteristics and medical comorbidities. Medical comorbidities were quantified using the modified Charlson Comorbidity Index (CCI). Values associated with the outcomes of interest were then subjected to multivariable logistic regression to identify independent predictors of readmission and reoperation. RESULTS: A total of 345 cases were identified. Mean age was 59.4 ± 11.7 years, 56% were male, and the racial makeup was 64% white, 29% black, and 7.3% other. Forty-two patients (12.2%) had unplanned readmissions, most commonly for wound infection with dehiscence (14.2%), venous thromboembolism (14.2%), and bowel obstruction/complication (11.9%). Thirteen patients required reoperation (4%), most commonly for wound infection with dehiscence (39%) or local recurrence (23%). Multivariable analysis showed that the modified CCI (odds ratio [OR], 1.25; 95% confidence interval [CI] 1.03-1.52; P = 0.03) was an independent predictor of 30-day readmission. Independent predictors of 30-day unplanned reoperation were: black (vs. white) race (OR, 0.08; 95% CI, 0.01-0.41; P < 0.01), length of stay (OR, 1.05 per day; 95% CI, 1.00-1.09; P = 0.04), and CCI (OR, 1.72 per point; 95% CI, 1.29-2.28; P < 0.01). CONCLUSIONS: Increasing medical comorbidities is independently predictive of both 30-day unplanned readmission and reoperation after spinal metastasis surgery. Unplanned reoperation is also positively predicted by a longer index admission. Neither tumor pathology nor age predicted outcome, suggesting that poor wound-healing factors and increased surgical morbidity may best predict these adverse outcomes.

A Web-Based Calculator for Predicting the Occurrence of Wound Complications, Wound Infection, and Unplanned Reoperation for Wound Complications in Patients Undergoing Surgery for Spinal Metastases.

BACKGROUND: In the present study, we identified the risk factors for wound complications, wound infection, and reoperation for wound complications after spine metastasis surgery and deployed the resultant model as a web-based calculator. METHODS: Patients treated at a single comprehensive cancer center during a 7-year period were included. The demographics, pathology, comorbidities, laboratory values, and operative details were collected. Factors with P < 0.15 on univariable regression were entered into multivariable logistic regression to generate predictive models internally validated using 1000 bootstrapped samples. RESULTS: Of the 330 patients included, 29 (7.6%) had experienced a surgical site infection. The independent predictive factors for wound-related complications were a higher Charlson comorbidity index (CCI; odds ratio [OR], 1.41 per point; P < 0.01), Karnofsky performance scale score ≤70 (OR, 2.14; P = 0.04), lower platelet count (OR, 0.49 per 105/µL; P < 0.01), revision versus index surgery (OR, 3.10; P = 0.02), and increased incision length (OR, 1.21 per level; P = 0.02). Wound infection was associated with a higher CCI (OR, 1.60 per point; P < 0.01), a lower platelet count (OR, 0.35 per 105/µL; P < 0.01), revision surgery (OR, 4.63; P = 0.01), and a longer incision length (OR, 1.25 per level; P = 0.03). Unplanned reoperation for wound complications was predicted by a higher CCI (OR, 1.39 per point; P = 0.003), prior irradiation (OR, 2.52; P = 0.04), a lower platelet count (OR, 0.57 per 105/µL; P = 0.02), and revision surgery (OR, 3.34; P = 0.03), The optimism-corrected areas under the curve were 0.75, 0.81, and 0.72 for the wound complication, infection, and reoperation models, respectively. CONCLUSIONS: Low platelet counts, poorer health status, more invasive surgery, and revision surgery all independently predicted the risk of wound complications, including infection and unplanned reoperation for infection. Validation of the calculators in a prospective study is merited.

Plastic surgery wound closure following resection of spinal metastases.

OBJECTIVE: Surgical site infection and dehiscence are devastating complications of surgery for spinal metastases. Wound closure involving plastic surgeons has been proposed as a strategy to lower post-operative complications. Here we investigated whether plastic surgery closure is associated with lower rates of wound complications, wound infection, and wound reoperation compared to simple closure by spine surgeons. METHODS: Patients surgically treated for metastatic tumors at a single comprehensive cancer center between April 2013-2020 were retrospectively identified. Primary pathology, demographic information, clinical characteristics, pre-operative laboratory values, tumor location, operative characteristics, and post-operative outcomes were collected. Univariable analyses used student t-tests for continuous variables and χ2 tests for categorical variables. Multivariable regressions were performed to control for confounders. RESULTS: We included 317 patients, of which 56 underwent closure by plastic surgeons and 291 by neurosurgeons. Patients in the plastic surgery cohort were more likely to have received prior radiation to the surgical site, more often on long-term corticosteroid therapy, and more likely to have sacrococcygeal tumors. Operations involving plastic surgeons were more likely to be revision surgeries, corpectomies, and to involve a staged approach. Additionally, patients in the plastic surgery cohort had longer incision lengths, longer surgeries, greater intraoperative blood loss (IOBL), were more likely to receive transfusions, and had longer hospitalizations. Local paraspinous advancement flaps were the most common complex wound closure technique. Plastic surgery closure was not significantly associated with a difference in rates of post-operative wound complications, wound infection, or wound-related reoperations compared to simple wound closure. CONCLUSION: We identified that patients undergoing plastic surgery wound closure had worse baseline risk, longer surgeries, greater IOBL, and longer hospitalizations compared to patients receiving simple closure. Despite their increased risk, complex wound closure did not significantly alter the rates of post-operative wound complications, wound infection, or wound-related reoperations. Consideration may be given to plastic surgery closure in patients at high risk of wound complications or with extensive wound defects.

Impact of Multidisciplinary Intraoperative Teams on Thirty-Day Complications After Sacral Tumor Resection.

OBJECTIVE: To evaluate the impact of multidisciplinary intraoperative teams on surgical complications in patients undergoing sacral tumor resection. METHODS: We reviewed all patients with primary or metastatic sacral tumors managed at a single comprehensive cancer center over a 7-year period. Perioperative complication rates were compared between those treated by an unassisted spinal oncologist and those treated with the assistance of at least 1 other surgical specialty. Statistical analysis involved univariable and stepwise multivariable logistic regression models to identify predictors of multidisciplinary management and 30-day complications. RESULTS: A total of 107 patients underwent 132 operations for sacral tumors; 92 operations involved multidisciplinary teams, including 54% of metastatic tumor operations and 74% of primary tumor operations. Patients receiving multidisciplinary management had higher body mass indexes (29.8 vs. 26.3 kg/m2; P = 0.008), larger tumors (258 vs. 55 cm³; P < 0.001), and higher American Society of Anesthesiologists scores (3 vs. 2; P = 0.049). Only larger tumor volume (odds ratio [OR], 1.007 per cm³; P < 0.001) and undergoing treatment for a malignant primary versus a metastatic tumor (OR, 23.4; P < 0.001) or benign primary tumor (OR, 29.3; P < 0.001) were predictive of multidisciplinary management. Although operations involving multidisciplinary teams were longer (467 vs. 231 minutes; P < 0.001) and had higher blood loss (1698 vs. 774 mL; P = 0.004), 30-day complication rates were similar (37 vs. 27%; P = 0.39). On multivariable analysis, only larger tumor volume (OR, 1.004 per cm³; P = 0.005) and longer surgical duration (OR, 1.002 per minute; P = 0.03) independently predicted higher 30-day complications. CONCLUSIONS: Although patients managed with multidisciplinary teams had larger tumors and worse baseline health, 30-day complications were similar. This finding suggests that the use of multidisciplinary teams may help to mitigate surgical morbidity in those with high baseline risk.

Sacrectomy for sacral tumors: perioperative outcomes in a large-volume comprehensive cancer center.

BACKGROUND CONTEXT: Sacral tumors are incredibly rare lesions affecting fewer than one in every 10,000 persons. Reported perioperative morbidity rates range widely, varying from 30% to 70%, due to the relatively low volumes seen by most centers. Factors affecting perioperative outcome following sacrectomy remain ill-defined. PURPOSE: To characterize perioperative outcomes of sacral tumor patients undergoing sacrectomy and identify independent risk factors of perioperative morbidity STUDY DESIGN/SETTING: Retrospective cohort study at a single comprehensive cancer center PATIENT SAMPLE: Consecutively treated sacral tumor patients (primary or metastatic) undergoing sacrectomy for oncologic resection between April 2013 and April 2020 OUTCOME MEASURES: Perioperative complications, hospital length of stay, non-home discharge, 30-day readmission, and 30-day reoperation METHODS: Details were gathered about tumor pathology and morphology, surgery performed, baseline medical comorbidities, preoperative lab data, and patient demographics. Stepwise multivariable regressions were conducted to identify independent risk factors of perioperative outcomes while evaluating predictive accuracy. RESULTS: 57 sacral tumor patients were included (mean age 55.5±13.0 years; 60% female). The complication, non-home discharge, 30-day readmission, and 30-day reoperation rates were 39%, 56%, 16%, and 14%, respectively. Independent predictors of perioperative complications included ASA>2 (OR=10.7; 95%CI [1.3, 86.0]; p=0.026), radicular pain (OR=10.9; p=0.014), platelet count (OR=0.989 per 10³/µL; p=0.049), and instrumentation (OR=10.7; p=0.009). Independent predictors of length of stay included iliac vessel involvement (ß=15.8; p=0.005), larger tumor volume (ß=0.027 per cm³; p<0.001), a staged procedure (ß=10.0; p=0.018), and S1 nerve root sacrifice (OR=15.8; p=.011). The optimal model predictive of non-home discharge included bilateral S3-S5 or higher nerve root sacrifice (OR=3.9; p=0.054), instrumentation (OR=8.6; p=0.005), and vertical rectus abdominis musculocutaneous flap closure (OR=5.3; p=0.067). 30-day readmission was independently predicted by history of chronic kidney disease (OR=26.7; p=0.021), radicular pain (OR=8.1; p=0.039), and preoperative saddle anesthesia (OR=12.6; p=0.026). All multivariable models achieved good discrimination (AUC>0.8 and R2>0.7). CONCLUSION: Clinical and operative factors were important predictors of complications and 30-day readmission, while tumor-related and operative factors accounted for most of the variability in length of stay and non-home discharge.

A clinical calculator for predicting intraoperative blood loss and transfusion risk in spine tumor patients.

BACKGROUND CONTEXT: Surgery for vertebral column tumors is commonly associated with intraoperative blood loss (IOBL) exceeding 2 liters and the need for transfusion of allogeneic blood products. Transfusion of allogeneic blood, while necessary, is not benign, and has been associated with increased rates of wound complication, venous thromboembolism, delirium, and death. PURPOSE: To develop a prediction tool capable of predicting IOBL and risk of requiring allogeneic transfusion in patients undergoing surgery for vertebral column tumors. STUDY DESIGN/SETTING: Retrospective, single-center study. PATIENT SAMPLE: Consecutive series of 274 patients undergoing 350 unique operations for primary or metastatic spinal column tumors over a 46-month period at a comprehensive cancer center OUTCOME MEASURES: IOBL (in mL), use of intraoperative blood products, and intraoperative blood products transfused. METHODS: We identified IOBL and transfusions, along with demographic data, preoperative laboratory data, and surgical procedures performed. Independent predictors of IOBL and transfusion risk were identified using multivariable regression. RESULTS: Mean age at surgery was 57.0±13.6 years, 53.1% were male, and 67.1% were treated for metastatic lesions. Independent predictors of IOBL included en bloc resection (p<.001), surgical invasiveness (ß=25.43 per point; p<0.001), and preoperative albumin (ß=-244.86 per g/dL; p=0.011). Predictors of transfusion risk included preoperative hematocrit (odds ratio [OR]=0.88 per %; 95% confidence interval [CI, 0.84, 0.93]; p<0.001), preoperative MCHgb (OR=0.88 per pg; 95% CI [0.78, 1.00]; p=0.048), preoperative red cell distribution width (OR=1.32 per %; 95% CI [1.13, 1.55]; p<0.001), en bloc resection (OR=3.17; 95%CI [1.33, 7.54]; p=0.009), and surgical invasiveness (OR=1.08 per point; [1.06; 1.11]; p<0.001). The transfusion model showed a good fit of the data with an optimism-corrected area under the curve of 0.819. A freely available, web-based calculator was developed for the transfusion risk model (https://jhuspine3.shinyapps.io/TRUST/). CONCLUSIONS: Here we present the first clinical calculator for intraoperative blood loss and transfusion risk in patients being treated for primary or metastatic vertebral column tumors. Surgical invasiveness and preoperative microcytic anemia most strongly predict transfusion risk. The resultant calculators may prove clinically useful for surgeons counseling patients about their individual risk of requiring allogeneic transfusion.

Predicting nonroutine discharge in patients undergoing surgery for vertebral column tumors.

OBJECTIVE: More than 8000 patients are treated annually for vertebral column tumors, of whom roughly two-thirds will be discharged to an inpatient facility (nonroutine discharge). Nonroutine discharge is associated with increased care costs as well as delays in discharge and poorer patient outcomes. In this study, the authors sought to develop a prediction model of nonroutine discharge in the population of vertebral column tumor patients. METHODS: Patients treated for primary or metastatic vertebral column tumors at a single comprehensive cancer center were identified for inclusion. Data were gathered regarding surgical procedure, patient demographics, insurance status, and medical comorbidities. Frailty was assessed using the modified 5-item Frailty Index (mFI-5) and medical complexity was assessed using the modified Charlson Comorbidity Index (mCCI). Multivariable logistic regression was used to identify independent predictors of nonroutine discharge, and multivariable linear regression was used to identify predictors of prolonged length of stay (LOS). The discharge model was internally validated using 1000 bootstrapped samples. RESULTS: The authors identified 350 patients (mean age 57.0 ± 13.6 years, 53.1% male, and 67.1% treated for metastatic vs primary disease). Significant predictors of prolonged LOS included higher mCCI score (ß = 0.74; p = 0.026), higher serum absolute neutrophil count (ß = 0.35; p = 0.001), lower hematocrit (ß = -0.34; p = 0.001), use of a staged operation (ß = 4.99; p < 0.001), occurrence of postoperative pulmonary embolism (ß = 3.93; p = 0.004), and surgical site infection (ß = 9.93; p < 0.001). Significant predictors of nonroutine discharge included emergency admission (OR 3.09; p = 0.001), higher mFI-5 score (OR 1.90; p = 0.001), lower serum albumin level (OR 0.43 per g/dL; p < 0.001), and operations with multiple stages (OR 4.10; p < 0.001). The resulting statistical model was deployed as a web-based calculator (https://jhuspine4.shinyapps.io/Nonroutine_Discharge_Tumor/). CONCLUSIONS: The authors found that nonroutine discharge of patients with surgically treated vertebral column tumors was predicted by emergency admission, increased frailty, lower serum albumin level, and staged surgical procedures. The resulting web-based calculator tool may be useful clinically to aid in discharge planning for spinal oncology patients by preoperatively identifying patients likely to require placement in an inpatient facility postoperatively.

Minimizing Blood Loss in Spine Surgery.

STUDY DESIGN: Broad narrative review. OBJECTIVE: To review and summarize the current literature on guidelines, outcomes, techniques and indications surrounding multiple modalities of minimizing blood loss in spine surgery. METHODS: A thorough review of peer-reviewed literature was performed on the guidelines, outcomes, techniques, and indications for multiple modalities of minimizing blood loss in spine surgery. RESULTS: There is a large body of literature that provides a consensus on guidelines regarding the appropriate timing of discontinuation of anticoagulation, aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and herbal supplements prior to surgery. Additionally, there is a more heterogenous discussion the utility of preoperative autologous blood donation facilitated by erythropoietin and iron supplementation for healthy patients slated for procedures with high anticipated blood loss and for whom allogeneic transfusion is likely. Intraoperative maneuvers available to minimize blood loss include positioning and maintaining normothermia. Tranexamic acid (TXA), bipolar sealer electrocautery, and topical hemostatic agents, and hypotensive anesthesia (mean arterial pressure (MAP) <65 mm Hg) should be strongly considered in cases with larger exposures and higher anticipated blood loss. There is strong level 1 evidence for the use of TXA in spine surgery as it reduces the overall blood loss and transfusion requirements. CONCLUSION: As the volume and complexity of spinal procedures rise, intraoperative blood loss management has become a pivotal topic of research within the field. There are many tools for minimizing blood loss in patients undergoing spine surgery. The current literature supports combining techniques to use a cost- effective multimodal approach to minimize blood loss in the perioperative period.