Browse

You are looking at 1 - 10 of 22 items for :

  • Journal of Neurosurgery: Spine x
  • By Author: Bydon, Mohamad x
Clear All
Restricted access

Hannah E. Gilder, Ross C. Puffer, Mohamad Bydon and Robert J. Spinner

OBJECTIVE

In this study, the authors sought to compare tumors with intradural extension to those remaining in the epidural or paraspinal space with the hypothesis that intradural extension may be a mechanism for seeding of the CSF with malignant cells, thereby resulting in higher rates of CNS metastases and shorter overall survival.

METHODS

The authors searched the medical record for cases of malignant peripheral nerve sheath tumors (MPNSTs) identified from 1994 to 2017. The charts of the identified patients were then reviewed for tumor location to identify patients with paraspinal malignancy. All patients included in the study had tumor specimens that were reviewed in the surgical pathology department. Paraspinal tumors with intradural extension were identified in the lumbar, sacral, and spinal accessory nerves, and attempts were made to match this cohort to another cohort of patients who had paraspinal tumors of the cranial nerves and lumbar and sacral spinal regions without intradural extension. Further information was collected on all patients with and without intradural extension, including date of diagnosis by pathology specimen review; nerve or nerves of tumor origin; presence, location, and diagnostic date of any CNS metastases; and either the date of death or date of last follow-up.

RESULTS

The authors identified 6 of 179 (3.4%) patients who had intradural tumor extension and compared these patients with 12 patients who harbored paraspinal tumors that did not have intradural extension. All tumors were diagnosed as high-grade MPNSTs according to the surgical pathology findings. Four of 6 (66.7%) patients with intradural extension had documented CNS metastases. The presence of CNS metastases was significantly higher in the intradural group than in the paraspinal group (intradural, 66.7% vs paraspinal, 0%; p < 0.01). Time from diagnosis until death was 11.2 months in the intradural group and approximately 72 months in the paraspinal, extradural cohort.

CONCLUSIONS

In patients with intradural extension of paraspinal MPNSTs, significantly higher rates of CNS metastases are seen with a reduced interval of time from diagnosis to metastatic lesion detection. Intradural tumor extension is also a poor prognostic factor for survival, with these patients showing a reduced mean time from diagnosis to death.

Restricted access

Benjamin F. Mundell, Marcus J. Gates, Panagiotis Kerezoudis, Mohammed Ali Alvi, Brett A. Freedman, Ahmad Nassr, Samuel F. Hohmann and Mohamad Bydon

OBJECTIVE

From 1994 to 2006 outpatient spinal surgery increased 5-fold. The perceived cost savings with outcomes comparable to or better than those achieved with inpatient admission for the same procedures are desirable in an era where health expenditures are scrutinized. The increase in outpatient spine surgery is also driven by the proliferation of ambulatory surgery centers. In this study, the authors hypothesized that the total savings in outpatient spine surgery is largely driven by patient selection and biases toward healthier patients.

METHODS

A meta-analysis assessed patient selection factors and outcomes associated with outpatient spine procedures. Pooled odds ratios and mean differences were calculated using a Bayesian random-effects model. The authors extended this analysis in a novel way by using the results of the meta-analysis to examine cost data from an administrative database of academically affiliated hospitals. A Bayesian approach with priors informed by the meta-analysis was used to compare costs for inpatient and outpatient performance of anterior cervical discectomy and fusion (ACDF) and lumbar laminectomy.

RESULTS

Sixteen studies with a total of 370,195 patients met the inclusion criteria. Outpatient procedures were associated with younger patient age (mean difference [MD] −2.34, 95% credible interval [CrI] −4.39 to −0.34) and no diabetes diagnosis (odds ratio [OR] 0.78, 95% CrI 0.54–0.97). Outpatient procedures were associated with a lower likelihood of reoperation (OR 0.42, 95% CrI 0.16–0.80), 30-day readmission (OR 0.39, 95% CrI 0.16–0.74), and complications (OR 0.29, 95% CrI 0.15–0.50) and with lower overall costs (MD −$121,392.72, 95% CrI −$216,824.81 to −$23,632.92). Additional analysis of the national administrative data revealed more modest cost savings than those found in the meta-analysis for outpatient spine surgeries relative to inpatient spine surgeries. Estimated cost savings for both younger patients ($555 for those age 30–35 years [95% CrI −$733 to −$374]) and older patients ($7290 for those age 65–70 years [95% CrI −$7380 to −$7190]) were less than the overall cost savings found in the meta-analysis.

CONCLUSIONS

Compared to inpatient spine surgery, outpatient spine surgery was associated with better short-term outcomes and an initial reduction in direct costs. A selection bias for outpatient procedures toward younger, healthier patients may confound these results. The additional analysis of the national database suggests that cost savings in the outpatient setting may be less than previously reported and a result of outpatient procedures being offered more frequently to younger and healthier individuals.

Restricted access

Najib E. El Tecle, Nader S. Dahdaleh, Mohamad Bydon, Wilson Z. Ray, James C. Torner and Patrick W. Hitchon

OBJECTIVE

The natural history of complete spinal cord injury (SCI) is poorly studied. The classically quoted rate of improvement or conversion for patients with American Spinal Injury Association (ASIA) grade A (ASIA A) injuries is 15%–20%; however, data supporting this rate are very limited. In this paper, the authors conducted a meta-analysis of modern data reporting on ASIA A patients and evaluated factors affecting the natural history of the disease.

METHODS

The authors conducted a systematic literature review of all randomized clinical trials (RCTs) and observational studies of patients with traumatic SCI. The Embase, MEDLINE, PubMed, Scopus, CINAHL, and Cochrane databases were reviewed for all studies reporting on SCI and published after 1992. A meta-analysis was conducted using the DerSimonian and Laird (random-effects) model with a summary odds ratio analysis.

RESULTS

Eleven RCTs and 9 observational studies were included in the final analysis. Overall, the 20 included studies reported on 1162 patients with ASIA A injuries. The overall conversion rate was 28.1%, with 327 of 1162 patients improving to at least ASIA B. The overall rate of conversion noted in cervical spine injuries was 33.3%, whereas that in thoracic injuries was 30.6%. Patients undergoing early surgery had a higher rate of conversion (46.1%) than patients undergoing late surgery (25%) (OR 2.31, 95% CI 1.08–4.96, p = 0.03).

CONCLUSIONS

The overall rate of conversion of ASIA A SCIs from pooled data of prospective trials and observational series is 28.1%. This rate of conversion is higher than what is reported in the literature. Early surgery is predictive of a higher conversion rate. However, there are not enough data to provide conclusions pertaining to the efficacy of biological and medical therapies.

Free access

Anthony L. Asher, Clinton J. Devin, Brandon McCutcheon, Silky Chotai, Kristin R. Archer, Hui Nian, Frank E. Harrell Jr., Matthew McGirt, Praveen V. Mummaneni, Christopher I. Shaffrey, Kevin Foley, Steven D. Glassman and Mohamad Bydon

OBJECTIVE

In this analysis the authors compare the characteristics of smokers to nonsmokers using demographic, socioeconomic, and comorbidity variables. They also investigate which of these characteristics are most strongly associated with smoking status. Finally, the authors investigate whether the association between known patient risk factors and disability outcome is differentially modified by patient smoking status for those who have undergone surgery for lumbar degeneration.

METHODS

A total of 7547 patients undergoing degenerative lumbar surgery were entered into a prospective multicenter registry (Quality Outcomes Database [QOD]). A retrospective analysis of the prospectively collected data was conducted. Patients were dichotomized as smokers (current smokers) and nonsmokers. Multivariable logistic regression analysis fitted for patient smoking status and subsequent measurement of variable importance was performed to identify the strongest patient characteristics associated with smoking status. Multivariable linear regression models fitted for 12-month Oswestry Disability Index (ODI) scores in subsets of smokers and nonsmokers was performed to investigate whether differential effects of risk factors by smoking status might be present.

RESULTS

In total, 18% (n = 1365) of patients were smokers and 82% (n = 6182) were nonsmokers. In a multivariable logistic regression analysis, the factors significantly associated with patients’ smoking status were sex (p < 0.0001), age (p < 0.0001), body mass index (p < 0.0001), educational status (p < 0.0001), insurance status (p < 0.001), and employment/occupation (p = 0.0024). Patients with diabetes had lowers odds of being a smoker (p = 0.0008), while patients with coronary artery disease had greater odds of being a smoker (p = 0.044). Patients’ propensity for smoking was also significantly associated with higher American Society of Anesthesiologists (ASA) class (p < 0.0001), anterior-alone surgical approach (p = 0.018), greater number of levels (p = 0.0246), decompression only (p = 0.0001), and higher baseline ODI score (p < 0.0001). In a multivariable proportional odds logistic regression model, the adjusted odds ratio of risk factors and direction of improvement in 12-month ODI scores remained similar between the subsets of smokers and nonsmokers.

CONCLUSIONS

Using a large, national, multiinstitutional registry, the authors described the profile of patients who undergo lumbar spine surgery and its association with their smoking status. Compared with nonsmokers, smokers were younger, male, nondiabetic, nonobese patients presenting with leg pain more so than back pain, with higher ASA classes, higher disability, less education, more likely to be unemployed, and with Medicaid/uninsured insurance status. Smoking status did not affect the association between these risk factors and 12-month ODI outcome, suggesting that interventions for modifiable risk factors are equally efficacious between smokers and nonsmokers.

Full access

Mohamed Macki, Rafael De la Garza-Ramos, Ashley A. Murgatroyd, Kenneth P. Mullinix, Xiaolei Sun, Bryan W. Cunningham, Brandon A. McCutcheon, Mohamad Bydon and Ziya L. Gokaslan

OBJECTIVE

Aggressive sacral tumors often require en bloc resection and lumbopelvic reconstruction. Instrumentation failure and pseudarthrosis remain a clinical concern to be addressed. The objective in this study was to compare the biomechanical stability of 3 distinct techniques for sacral reconstruction in vitro.

METHODS

In a human cadaveric model study, 8 intact human lumbopelvic specimens (L2–pelvis) were tested for flexion-extension range of motion (ROM), lateral bending, and axial rotation with a custom-designed 6-df spine simulator as well as axial compression stiffness with the MTS 858 Bionix Test System. Biomechanical testing followed this sequence: 1) intact spine; 2) sacrectomy (no testing); 3) Model 1 (L3–5 transpedicular instrumentation plus spinal rods anchored to iliac screws); 4) Model 2 (addition of transiliac rod); and 5) Model 3 (removal of transiliac rod; addition of 2 spinal rods and 2 S-2 screws). Range of motion was measured at L4–5, L5–S1/cross-link, L5–right ilium, and L5–left ilium.

RESULTS

Flexion-extension ROM of the intact specimen at L4–5 (6.34° ± 2.57°) was significantly greater than in Model 1 (1.54° ± 0.94°), Model 2 (1.51° ± 1.01°), and Model 3 (0.72° ± 0.62°) (p < 0.001). Flexion-extension at both the L5–right ilium (2.95° ± 1.27°) and the L5–left ilium (2.87° ± 1.40°) for Model 3 was significantly less than the other 3 cohorts at the same level (p = 0.005 and p = 0.012, respectively). Compared with the intact condition, all 3 reconstruction groups statistically significantly decreased lateral bending ROM at all measured points. Axial rotation ROM at L4–5 for Model 1 (2.01° ± 1.39°), Model 2 (2.00° ± 1.52°), and Model 3 (1.15° ± 0.80°) was significantly lower than the intact condition (5.02° ± 2.90°) (p < 0.001). Moreover, axial rotation for the intact condition and Model 3 at L5–right ilium (2.64° ± 1.36° and 2.93° ± 1.68°, respectively) and L5–left ilium (2.58° ± 1.43° and 2.93° ± 1.71°, respectively) was significantly lower than for Model 1 and Model 2 at L5–right ilium (5.14° ± 2.48° and 4.95° ± 2.45°, respectively) (p = 0.036) and L5–left ilium (5.19° ± 2.34° and 4.99° ± 2.31°) (p = 0.022). Last, results of the axial compression testing at all measured points were not statistically different among reconstructions.

CONCLUSIONS

The addition of a transverse bar in Model 2 offered no biomechanical advantage. Although the implementation of 4 iliac screws and 4 rods conferred a definitive kinematic advantage in Model 3, that model was associated with significantly restricted lumbopelvic ROM.

Full access

Matthew J. McGirt, Mohamad Bydon, Kristin R. Archer, Clinton J. Devin, Silky Chotai, Scott L. Parker, Hui Nian, Frank E. Harrell Jr., Theodore Speroff, Robert S. Dittus, Sharon E. Philips, Christopher I. Shaffrey, Kevin T. Foley and Anthony L. Asher

OBJECTIVE

Quality and outcomes registry platforms lie at the center of many emerging evidence-driven reform models. Specifically, clinical registry data are progressively informing health care decision-making. In this analysis, the authors used data from a national prospective outcomes registry (the Quality Outcomes Database) to develop a predictive model for 12-month postoperative pain, disability, and quality of life (QOL) in patients undergoing elective lumbar spine surgery.

METHODS

Included in this analysis were 7618 patients who had completed 12 months of follow-up. The authors prospectively assessed baseline and 12-month patient-reported outcomes (PROs) via telephone interviews. The PROs assessed were those ascertained using the Oswestry Disability Index (ODI), EQ-5D, and numeric rating scale (NRS) for back pain (BP) and leg pain (LP). Variables analyzed for the predictive model included age, gender, body mass index, race, education level, history of prior surgery, smoking status, comorbid conditions, American Society of Anesthesiologists (ASA) score, symptom duration, indication for surgery, number of levels surgically treated, history of fusion surgery, surgical approach, receipt of workers’ compensation, liability insurance, insurance status, and ambulatory ability. To create a predictive model, each 12-month PRO was treated as an ordinal dependent variable and a separate proportional-odds ordinal logistic regression model was fitted for each PRO.

RESULTS

There was a significant improvement in all PROs (p < 0.0001) at 12 months following lumbar spine surgery. The most important predictors of overall disability, QOL, and pain outcomes following lumbar spine surgery were employment status, baseline NRS-BP scores, psychological distress, baseline ODI scores, level of education, workers’ compensation status, symptom duration, race, baseline NRS-LP scores, ASA score, age, predominant symptom, smoking status, and insurance status. The prediction discrimination of the 4 separate novel predictive models was good, with a c-index of 0.69 for ODI, 0.69 for EQ-5D, 0.67 for NRS-BP, and 0.64 for NRS-LP (i.e., good concordance between predicted outcomes and observed outcomes).

CONCLUSIONS

This study found that preoperative patient-specific factors derived from a prospective national outcomes registry significantly influence PRO measures of treatment effectiveness at 12 months after lumbar surgery. Novel predictive models constructed with these data hold the potential to improve surgical effectiveness and the overall value of spine surgery by optimizing patient selection and identifying important modifiable factors before a surgery even takes place. Furthermore, these models can advance patient-focused care when used as shared decision-making tools during preoperative patient counseling.

Full access

Anthony L. Asher, Clinton J. Devin, Kristin R. Archer, Silky Chotai, Scott L. Parker, Mohamad Bydon, Hui Nian, Frank E. Harrell Jr., Theodore Speroff, Robert S. Dittus, Sharon E. Philips, Christopher I. Shaffrey, Kevin T. Foley and Matthew J. McGirt

OBJECTIVE

Current costs associated with spine care are unsustainable. Productivity loss and time away from work for patients who were once gainfully employed contributes greatly to the financial burden experienced by individuals and, more broadly, society. Therefore, it is vital to identify the factors associated with return to work (RTW) after lumbar spine surgery. In this analysis, the authors used data from a national prospective outcomes registry to create a predictive model of patients’ ability to RTW after undergoing lumbar spine surgery for degenerative spine disease.

METHODS

Data from 4694 patients who underwent elective spine surgery for degenerative lumbar disease, who had been employed preoperatively, and who had completed a 3-month follow-up evaluation, were entered into a prospective, multicenter registry. Patient-reported outcomes—Oswestry Disability Index (ODI), numeric rating scale (NRS) for back pain (BP) and leg pain (LP), and EQ-5D scores—were recorded at baseline and at 3 months postoperatively. The time to RTW was defined as the period between operation and date of returning to work. A multivariable Cox proportional hazards regression model, including an array of preoperative factors, was fitted for RTW. The model performance was measured using the concordance index (c-index).

RESULTS

Eighty-two percent of patients (n = 3855) returned to work within 3 months postoperatively. The risk-adjusted predictors of a lower likelihood of RTW were being preoperatively employed but not working at the time of presentation, manual labor as an occupation, worker’s compensation, liability insurance for disability, higher preoperative ODI score, higher preoperative NRS-BP score, and demographic factors such as female sex, African American race, history of diabetes, and higher American Society of Anesthesiologists score. The likelihood of a RTW within 3 months was higher in patients with higher education level than in those with less than high school–level education. The c-index of the model’s performance was 0.71.

CONCLUSIONS

This study presents a novel predictive model for the probability of returning to work after lumbar spine surgery. Spine care providers can use this model to educate patients and encourage them in shared decision-making regarding the RTW outcome. This evidence-based decision support will result in better communication between patients and clinicians and improve postoperative recovery expectations, which will ultimately increase the likelihood of a positive RTW trajectory.

Full access

Charles H. Crawford III, Leah Y. Carreon, Mohamad Bydon, Anthony L. Asher and Steven D. Glassman

OBJECTIVE

Patient satisfaction is a commonly used metric in the current health care environment. While factors that affect patient satisfaction following spine surgery are complex, the authors of this study hypothesized that specific diagnostic groups of patients are more likely to be satisfied after spine surgery and that this is reflected in patient-reported outcome measures. The purpose of this study was to determine if the preoperative diagnosis—disc herniation, stenosis, spondylolisthesis, adjacent segment degeneration, or mechanical disc collapse—would impact patient satisfaction following surgery.

METHODS

Patients enrolled in the Quality Outcomes Database, formerly known as the National Neurosurgery Quality and Outcomes Database (N2QOD), completed patient-reported outcome measures, including the Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS) for back pain (NRS-BP) and leg pain (NRS-LP) preoperatively and 1-year postoperatively. Patients were stratified by diagnosis and by their response to the satisfaction question: 1) surgery met my expectations; 2) I did not improve as much as I hoped, but I would undergo the same operation for the same results; 3) surgery helped, but I would not undergo the same operation for the same results; or 4) I am the same or worse as compared with before surgery.

RESULTS

A greater proportion of patients with primary disc herniation or spondylolisthesis reported that surgery met expectations (66% and 67%, respectively), followed by recurrent disc herniation and stenosis (59% and 60%, respectively). A smaller proportion of patients who underwent surgery for adjacent segment degeneration or mechanical disc collapse had their expectations met (48% and 41%, respectively). The percentage of patients that would undergo the same surgery again, by diagnostic group, was as follows: disc herniation 88%, recurrent disc herniation 79%, spondylolisthesis 86%, stenosis 82%, adjacent segment disease 75%, and mechanical collapse 73%. Regardless of diagnosis, mean improvement and ultimate 1-year postoperative ODI, NRS-BP, and NRS-LP reflected patient satisfaction.

CONCLUSIONS

Preoperative diagnosis was predictive of patient satisfaction following spine surgery. The mean change in and 1-year ODI, NRS-BP, and NRS-LP reflected patient satisfaction regardless of preoperative diagnosis.

Full access

Meghan E. Murphy, Hannah Gilder, Patrick R. Maloney, Brandon A. McCutcheon, Lorenzo Rinaldo, Daniel Shepherd, Panagiotis Kerezoudis, Daniel S. Ubl, Cynthia S. Crowson, William E. Krauss, Elizabeth B. Habermann and Mohamad Bydon

OBJECTIVE

With improving medical therapies for chronic conditions, elderly patients increasingly present as candidates for operative intervention for degenerative diseases of the spine. To date, there is a paucity of studies examining complications in lumbar decompression, without fusion, that include patients older than 80 years. Using a multicenter national database, the authors of this study evaluated lumbar decompression in the elderly, including octogenarians, to evaluate for associations between age and patient outcomes.

METHODS

The 2011–2013 American College of Surgeons' National Surgical Quality Improvement Program data set was queried for patients 65 years and older with diagnosis and procedure codes inclusive of degenerative spine disease and lumbar decompression without fusion. Morbidity and mortality within the 30-day postoperative period were the primary outcomes. Secondary outcomes of interest included unplanned readmission within 30 days or discharge to a nonhome facility. Outcomes and operative characteristics were compared using chi-square tests, Kruskal-Wallis tests, and multivariable logistic regression models.

RESULTS

A total of 8744 patients were identified; of these patients 4573 (52.30%) were 65 years and older. Elderly patients were stratified into 3 age categories: 85 years or older (n = 314), 75–84 years (n = 1663), and 65–74 years (n = 2596). Univariate analysis showed that, compared with age younger than 65 years, increased age was associated with the number of levels (≥ 3), readmissions within 30 days, nonhome discharge, any complication, length of stay, and blood transfusion (all p < 0.001). On multivariable analysis and with younger than 65 years as the reference, increased age was associated with any minor complication (p < 0.001; ≥ 85 years: OR 3.47, 95% CI 1.69–7.13; 75–84 years: OR 2.34, 95% CI 1.45–3.78; and 65–74 years: OR 1.44, 95% CI 0.94–2.20), as well as discharge location other than home (p < 0.001; ≥ 85 years: OR 13.59, 95% CI 9.47–19.49; 75–84 years: OR 5.64, 95% CI 4.33–7.34; and 65–74 years: OR 2.61, 95% CI 2.05–3.32).

CONCLUSIONS

The authors' high-powered, multicenter analysis of lumbar decompression without fusion in the elderly, specifically including patients older than 80 years, demonstrates that increased age is associated with more extensive operations, resulting in longer hospital stays, increased rates of nonhome discharge, and minor complications.

Full access

Anthony L. Asher, Silky Chotai, Clinton J. Devin, Theodore Speroff, Frank E. Harrell Jr., Hui Nian, Robert S. Dittus, Praveen V. Mummaneni, John J. Knightly, Steven D. Glassman, Mohamad Bydon, Kristin R. Archer, Kevin T. Foley and Matthew J. McGirt

OBJECTIVE

Prospective longitudinal outcomes registries are at the center of evidence-driven health care reform. Obtaining real-world outcomes data at 12 months can be costly and challenging. In the present study, the authors analyzed whether 3-month outcome measurements sufficiently represent 12-month outcomes for patients with degenerative lumbar disease undergoing surgery.

METHODS

Data from 3073 patients undergoing elective spine surgery for degenerative lumbar disease were entered into a prospective multicenter registry (N2QOD). Baseline, 3-month, and 12-month follow-up Oswestry Disability Index (ODI) scores were recorded. The absolute differences between actual 12- and 3-month ODI scores was evaluated. Additionally, the authors analyzed the absolute difference between actual 12-month ODI scores and a model-predicted 12-month ODI score (the model used patients' baseline characteristics and actual 3-month scores). The minimal clinically important difference (MCID) for ODI of 12.8 points and the substantial clinical benefit (SCB) for ODI of 18.8 points were used based on the previously published values. The concordance rate of achieving MCID and SCB for ODI at 3-and 12-months was computed.

RESULTS

The 3-month ODI scores differed from 12-month scores by an absolute difference of 11.9 ± 10.8, and predictive modeling estimations of 12-month ODI scores differed from actual 12-month scores by a mean (± SD) of 10.7 ± 9.0 points (p = 0.001). Sixty-four percent of patients (n = 1982) achieved an MCID for ODI at 3 months in comparison with 67% of patients (n = 2088) by 12 months; 51% (n = 1731) and 61% (n = 1860) of patients achieved SCB for ODI at 3 months and 12 months, respectively. Almost 20% of patients had ODI scores that varied at least 20 points (the point span of an ODI functional category) between actual 3- and 12-month values. In the aggregate analysis of achieving MCID, 77% of patients were concordant and 23% were discordant in achieving or not achieving MCID at 3 and 12 months. The discordance rates of achieving or not achieving MCID for ODI were in the range of 19% to 27% for all diagnoses and treatments (decompression with and without fusion). The positive and negative predictive value of 3-months ODI to predict 12-month ODI was 86% and 60% for MCID and 82% and 67% for SCB.

CONCLUSIONS

Based on their findings, the authors conclude the following: 1) Predictive methods for functional outcome based on early patient experience (i.e., baseline and/or 3-month data) should be used to help evaluate the effectiveness of procedures in patient populations, rather than serving as a proxy for long-term individual patient experience. 2) Prospective longitudinal registries need to span at least 12 months to determine the effectiveness of spine care at the individual patient and practitioner level.