Cost Analysis of Single-Level Lumbar Fusions

Study Design: Cost analysis of a retrospectively identified cohort of patients who had undergone primary single-level lumbar fusion at a single institution's orthopedic or neurosurgery department. Objective: The purpose of this article is to analyze the determinants of direct costs for single-level lumbar fusions and identify potential areas for cost reduction. Methods: Adult patients who underwent primary single-level lumbar fusion from fiscal years 2008 to 2012 were identified via administrative and departmental databases and were eligible for inclusion. Patients were excluded if they underwent multiple surgeries, had previous surgery at the same anatomic region, underwent corpectomy, kyphectomy, disc replacement, surgery for tumor or infection, or had incomplete cost data. Demographic data, surgical data, and direct cost data in the categories of supplies, services, room and care, and pharmacy, was collected for each patient. Results: The cohort included 532 patients. Direct costs ranged from $8286 to$73 727 (median = $21 781; mean =$22 890 +/- $6323). Surgical approach was an important determinant of cost. The mean direct cost was highest for the circumferential approach and lowest for posterior instrumented spinal fusions without an interbody cage. The difference in mean direct cost between transforaminal lumbar interbody fusions, anterior lumbar interbody fusions, and lateral transpsoas fusions was not statistically significant. Surgical supplies accounted for 44% of direct costs. Spinal implants were the primary component of supply costs (84.9%). Services accounted for 38% of direct costs and were highly dependent on operative time. Comorbidities were an important contributor to variance in the cost of care as evidenced by high variance in pharmacy costs and length of stay related to their management. Conclusion: The costs of spinal surgeries are highly variable. Important cost drivers in our analysis included surgical approach, implants, operating room time, and length of hospital stay. Areas of high cost and high variance offer potential targets for cost savings and quality improvements.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

How do validated measures of functional outcome compare with commonly used outcomes in administrative database research for lumbar spinal surgery?

Clinical interpretation of health services research based on administrative databases is limited by the lack of patient-reported functional outcome measures. Reoperation, as a surrogate measure for poor outcome, may be biased by preferences of patients and surgeons and may even be planned a priori. Other available administrative data outcomes, such as postoperative cross sectional imaging (PCSI), may better reflect changes in functional outcome. The purpose was to determine if postoperative events captured from administrative databases, namely reoperation and PCSI, reflect outcomes as derived by validated functional outcome measures (short form 36 scores, Oswestry disability index) for patients who underwent discretionary surgery for specific degenerative conditions of the lumbar spine such as disc herniation, spinal stenosis, degenerative spondylolisthesis, and isthmic spondylolisthesis. After reviewing the records of all patients surgically treated for disc herniation, spinal stenosis, degenerative spondylolisthesis, and isthmic spondylolisthesis at our institution, we recorded the occurrence of PCSI (MRI or CT-myelograms) and reoperations, as well as demographic, surgical, and functional outcome data. We determined how early (within 6 months) and intermediate (within 18 months) term events (PCSI and reoperations) were associated with changes in intermediate (minimum 1 year) and late (minimum 2 years) term functional outcome, respectively. We further evaluated how early (6–12 months) and intermediate (12–24 months) term changes in functional outcome were associated with the subsequent occurrence of intermediate (12–24 months) and late (beyond 24 months) term adverse events, respectively. From 148 surgically treated patients, we found no significant relationship between the occurrence of PCSI or reoperation and subsequent changes in functional outcome at intermediate or late term. Similarly, earlier changes in functional outcome did not have any significant relationship with subsequent occurrences of adverse events at intermediate or late term. Although it may be tempting to consider administrative database outcome measures as proxies for poor functional outcome, we cannot conclude that a significant relationship exists between the occurrence of PCSI or reoperation and changes in functional outcome

Patient Preferences, Referral Practices, and Surgeon Enthusiasm for Degenerative Lumbar Spinal Surgery

Degenerative disease of the lumbar spine (DDLS) is a common condition for which surgery is beneficial in selected patients. Wide variation in surgical referral and rates of surgery has been observed contributing to unequal access to care. Our objectives were to examine (1) the variation in preferences for referral and surgery among surgeons, family physicians (FPs) and patients, (2) how FP referral practices compare with preferences and guideline recommendations, and (3) how the ‘enthusiasm’ of patients and physicians influence regional variation in surgical rates. We used conjoint analysis in a mailed survey to elicit preferences based on clinical vignettes from surgeons, FPs and patients. A Delphi expert panel provided consensus guideline recommendations for surgical referral to compare with actual FP referral practices. Rates of surgery for DDLS, obtained from Ontario hospital discharge data, were used to quantify regional variation and regression models assessed the relationship with patient and physician enthusiasm. We identified significant differences in preferences for referral and surgery between patients, FPs and surgeons. Surgeons placed high importance on leg-dominant symptoms while patients had high importance for quality of life symptoms (i.e. severity, duration, walking tolerance). Surgical referral practices were poorly predicted by individual FP preferences and guideline recommendations based on clinical factors alone. Variation in Ontario surgical rates was higher than that of hip or knee replacements and was highly associated with the enthusiasm of surgeons (p<0.008), rather than FPs or patients. By appreciating the variation in preferences between patients and physicians, and exploring other non-clinical factors that influence referrals, we may be able to improve the efficiency of referrals and enhance the shared decision making process. With an understanding of the influence that surgeons have in driving variation in surgical rates, further research may allow us to direct strategies to improve access and allow for a more equitable delivery of care for patients suffering from DDLS.Ph

Estimation methods in random coefficient regression for continuous and binary longitudinal data

grantor: University of TorontoRandom coefficient regression (RCR) models are commonly used in the analysis of longitudinal data. Longitudinal studies involve a number of subjects on whom repeated outcome and explanatory measurements are taken over time. RCR is necessary since each subject may have a different relationship between the explanatory and outcome measurements. This thesis attempts to improve upon the current techniques used of estimation in RCR in two ways. First, the weighted least-squares estimator put forth by Swamy (16) is adapted to allow an iterative procedure to update the parameter estimates. This iterated weighted least-squares estimator is compared with the weighted least-squares and unweighted least-squares estimators. Second, these three RCR estimators are then extended, by analogy, to the case where the repeated outcome variable is binary. These theoretical methods are explained in detail, tested on simulated datasets, and used to analyze a longitudinal dataset in both the continuous and binary outcome cases.M.Sc

The Influence of Insurance Status on the Surgical Treatment of Acute Spinal Fractures

Study designA retrospective, propensity score, multivariate analysis of the National Trauma Data Bank (NTDB) between 2008 and 2011.ObjectiveThe aim of this study was to determine the relationship between insurance status and rates of surgery for acute spinal fractures with and without spinal cord injury (SCI).Summary of background dataThe decision for surgery in patients with spinal fractures is often based on fracture pattern and stability, associated SCI, and the presence of ligamentous and other associated injuries. It is poorly understood how nonclinical factors, such as insurance status, influence the decision for surgical intervention in patients sustaining spinal trauma.MethodsUsing NTDB admission years 2008 to 2011, we included patients 18 to 64 years old who sustained a fracture of the cervical or thoracolumbar spine. Patients were excluded if they sustained polytrauma (Injury Severity Score ≥27) or a major injury (Abbreviated Injury Scale severity ≥3) to the head, thorax, or abdomen. Our main outcome measure was surgical versus nonsurgical treatment for spinal injury; our main predictor was insurance status. Hierarchical multivariate regression analysis and propensity scores were used to determine the relationship between insurance status and surgical treatment, controlling for other factors. We calculated adjusted odds ratios (ORs) for rates of surgery.ResultsOur propensity score multivariate analysis demonstrated significantly higher rates of surgery in patients with SCI (OR = 11.76, P &lt; 0.001), insurance (OR = 1.27, P &lt; 0.001), white (OR = 1.21, P = 0.018) versus black race, blunt trauma (OR = 5.63, P &lt; 0.001), shock (OR = 1.62, P &lt; 0.001), higher Glasgow Coma Scale (GCS) score (OR = 1.02, P = 0.002), transfer from lower acuity hospital (OR = 1.51, P &lt; 0.001), and treatment at teaching hospitals (OR = 1.49, P &lt; 0.001). Multivariable subgroup analysis of SCI patients similarly revealed higher surgical rates for insured patients (OR = 1.46, P &lt; 0.001) than those without insurance.ConclusionPatients with traumatic spine fractures were more likely to receive surgery if they were insured, regardless of the presence of SCI

Drivers of surgery for the degenerative hip, knee, and spine: a systematic review.

Surgical treatment for degenerative conditions of the hip, knee, and spine has an impact on overall healthcare spending. Surgical rates have increased dramatically and considerable regional variation has been observed. The reasons behind these increasing rates and variation across regions have not been well elucidated.We therefore identified demographic (D), social structure (SS), health belief (HB), personal (PR) and community resources (CR), and medical need (MN) factors that drive rates of hip, knee, and spine surgery.We conducted a systematic review to include all observational, population-based studies that compared surgical rates with potential drivers (D, SS, HB, PR, CR, MN). We searched PubMed combining key words focusing on (1) disease and procedure; (2) study methodology; and (3) explanatory models. Independent investigators selected potentially eligible studies from abstract review and abstracted methodological and outcome data. From an initial search of 256 articles, we found 37 to be potentially eligible (kappa 0.86) but only 28 met all our inclusion criteria.Age, nonminority, insurance coverage, and surgeon enthusiasm all increased surgical rates. Rates of arthroplasty were higher for females with higher education, income, obesity, rurality, willingness to consider surgery, and prevalence of disease, whereas spinal rates increased with male gender, lower income, and the availability of advanced imaging.Regional variation in these procedures exists because they are examples of preference-sensitive care. With strategies that may affect change in factors that are potentially modifiable by behavior or resources, extreme variation in rates may be reduced

Drivers of surgery for the degenerative hip, knee, and spine: a systematic review.

Surgical treatment for degenerative conditions of the hip, knee, and spine has an impact on overall healthcare spending. Surgical rates have increased dramatically and considerable regional variation has been observed. The reasons behind these increasing rates and variation across regions have not been well elucidated.We therefore identified demographic (D), social structure (SS), health belief (HB), personal (PR) and community resources (CR), and medical need (MN) factors that drive rates of hip, knee, and spine surgery.We conducted a systematic review to include all observational, population-based studies that compared surgical rates with potential drivers (D, SS, HB, PR, CR, MN). We searched PubMed combining key words focusing on (1) disease and procedure; (2) study methodology; and (3) explanatory models. Independent investigators selected potentially eligible studies from abstract review and abstracted methodological and outcome data. From an initial search of 256 articles, we found 37 to be potentially eligible (kappa 0.86) but only 28 met all our inclusion criteria.Age, nonminority, insurance coverage, and surgeon enthusiasm all increased surgical rates. Rates of arthroplasty were higher for females with higher education, income, obesity, rurality, willingness to consider surgery, and prevalence of disease, whereas spinal rates increased with male gender, lower income, and the availability of advanced imaging.Regional variation in these procedures exists because they are examples of preference-sensitive care. With strategies that may affect change in factors that are potentially modifiable by behavior or resources, extreme variation in rates may be reduced