Describing the spine surgery learning curve during the first two years of independent practice.

ABSTRACT: Retrospective cohort studyTo characterize the learning curve of a spine surgeon during the first 2 years of independent practice by comparing to an experienced colleague. To stratify learning curves based on procedure to evaluate the effect of experience on surgical complexity.The learning curve for spine surgery is difficult to quantify, but is useful information for hospital administrators/surgical programs/new graduates, so appropriate expectations and accommodations are considered.Data from a retrospective cohort (2014-2016) were analyzed at a quaternary academic institution servicing a geographically-isolated, mostly rural area. Procedures included anterior cervical discectomy and fusion, posterior cervical decompression and stabilization, single and 2-level posterior lumbar interbody fusion, lumbar discectomy, and laminectomy. Data related to patient demographics, after-hours surgery, and revision surgery were collected. Operative time was the primary outcome measure, with secondary measures including cerebrospinal fluid leak and early re-operation. Time periods were stratified into 6 month quarters (quarter [Q] 1-Q4), with STATA software used for statistical analysis.There were 626 patients meeting inclusion criteria. The senior surgeon had similar operative times throughout the study. The new surgeon demonstrated a decrease in operative time from Q1 to Q4 (158 minutes-119 minutes, P < .05); however, the mean operative time was shorter for the senior surgeon at 2 years (91 minutes, P < .05). The senior surgeon performed more revision surgeries (odds ratio [OR] 2.5 [95% confidence interval [CI] 1.7-3.6]; P < .001). Posterior interbody fusion times remained longer for the new surgeon, while laminectomy surgery was similar to the senior surgeon by 2 years. There were no differences in rates of cerebrospinal fluid leak (OR 1.2 [95% CI 0.6-2.5]; P > .05), nor reoperation (OR 1.16 [95% CI 0.7-1.9]; P > .05) between surgeons.A significant learning curve exists starting spine practice and likely extends beyond the first 2 years for elective operations.

Dose Adjustment Associated Complications of Bone Morphogenetic Protein: A Longitudinal Assessment.

OBJECTIVE: Bone morphogenetic protein (BMP) is a growth factor that aids in osteoinduction and promotes bone fusion. There is a lack of literature regarding recombinant human BMP-2 (rhBMP-2) dosage in different spine surgeries. This study aims to investigate the trends in rhBMP-2 dosage and the associated complications in spinal arthrodesis. METHODS: A retrospective study was conducted investigating spinal arthrodesis using rhBMP-2. Variables including age, procedure type, rhBMP-2 size, complications, and postoperative imaging were collected. Cases were grouped into the following surgical procedures: anterior lumbar interbody fusion/extreme lateral interbody fusion (ALIF/XLIF), posterior lumbar interbody fusion/transforaminal lumbar interbody fusion (PLIF/TLIF), posterolateral fusion (PLF), anterior cervical discectomy and fusion (ACDF), and posterior cervical fusion (PCF). RESULTS: A total of 1209 patients who received rhBMP-2 from 2006 to 2020 were studied. Of these, 230 were categorized as ALIF/XLIF, 336 as PLIF/TLIF, 243 as PLF, 203 as ACDF, and 197 as PCF. PCF (P < 0.001), PLIF/TLIF (P < 0.001), and PLF (P < 0.001) demonstrated a significant decrease in the rhBMP-2 dose used per level, with major transitions seen in 2018, 2011, and 2013, respectively. In our sample, 129 complications following spinal arthrodesis were noted. A significant relation between rhBMP-2 size and complication rates (χ2= 73.73, P = 0.0029) was noted. rhBMP-2 dosage per level was a predictor of complication following spinal arthrodesis (odds ratio = 1.302 [1.05-1.55], P < 0.001). CONCLUSIONS: BMP is an effective compound in fusing adjacent spine segments. However, it carries some regional complications. We demonstrate a decreasing trend in the dose/vertebral level. A decrease rhBMP-2 dose per level correlated with a decrease in complication rates.

Evaluation of Benefit and Cost Utility of Immediate Postanesthesia Care Unit Radiographs to Predict Airway Compromise After Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective review. OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) is a commonly performed procedure that may be complicated by airway compromise postoperatively. This life-threatening complication may necessitate reintubation and reoperation. We evaluated the cost utility of conventional postoperative x-ray. SUMMARY OF BACKGROUND DATA: Studies have demonstrated minimal benefit in obtaining an x-ray on postoperative day 1, but there is some utility of postanesthesia care unit (PACU) x-rays for predicting the likelihood of reoperation. METHODS: We retrospectively reviewed the records of consecutive patients who underwent ACDF between September 2013 and February 2017. Patients were dichotomized into those who received PACU x-rays and those who did not (control group). Primary outcomes were reoperation, reintubation, mortality, and health care costs. RESULTS: Eight-hundred and fifteen patients were included in our analysis: 558 had PACU x-rays; 257 did not. In those who received PACU x-rays, mean age was 53.7 ±â€Š11.3 years, mean levels operated on were 2.0 ±â€Š0.79, and mean body mass index (BMI) was 30.3 ±â€Š6.9. In those who did not, mean age was 51.8 ±â€Š10.9 years, mean levels operated on were 1.48 ±â€Š0.65, and mean BMI was 29.9 ±â€Š6.3. Complications in the PACU x-ray group were reintubation-0.4%, reoperation-0.7%, and death-0.3% (due to prevertebral swelling causing airway compromise). Complications in the control group were reintubation-0.4%, reoperation-0.8%, and death-0. There were no differences between groups with respect to reoperation (P = 0.92), reintubation (P = 0.94), or mortality (P = 0.49). The mean per-patient cost was significantly higher (P = 0.009) in those who received PACU x-rays, $1031.76 ±â€Š948.67, versus those in the control group, $700.26 ±â€Š634.48. Mean length of stay was significantly longer in those who had PACU x-rays (P = 0.01). CONCLUSION: Although there were no differences in reoperation, reintubation, or mortality, there was a significantly higher cost for care and hospitalization in those who received PACU x-rays. Further studies are warranted to validate the results of the presented study.Level of Evidence: 3.

Factors Associated With Progression to Surgical Intervention for Lumbar Disc Herniation in the Military Health System.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To determine surgery-free survival of patients receiving conservative management of lumbar disc herniation (LDH) in the military healthcare system (MHS) and risk factors for surgical intervention. SUMMARY OF BACKGROUND DATA: Radiculopathy from LDH is a major cause of morbidity and cost. METHODS: The Military Data Repository was queried for all patients diagnosed with LDH from FY2011-2018; the earliest such diagnosis in a military treatment facility (MTF) was kept for each patient as the initial diagnosis. Follow-up time to surgical intervention was defined as the time from diagnosis to first encounter for lumbar microdiscectomy or lumbar decompression in either a MTF or in the civilian sector. The Military Data Repository was also queried for history of tobacco use at any time during MHS care, age at the time of diagnosis, sex, MHS beneficiary category, and diagnosing facility characteristics. Multivariable Cox proportional hazards models were used to evaluate the associations of patient and diagnosing facility characteristics with time to surgical intervention. RESULTS: A total of 84,985 MHS beneficiaries including 62,771 active duty service members were diagnosed with LDH in a MTF during the 8-year study period. A total of 10,532 (12.4%) MHS beneficiaries, including 7650 (10.9%) active duty, failed conservative management onto surgical intervention with lumbar microdiscectomy or lumbar decompression. Median follow-up time of the cohort was 5.2 (interquartile range 2.6, 7.5) years. Among all healthcare beneficiaries, several patient-level (younger age, male sex, and history of tobacco use) and facility-level characteristics (hospital vs. clinic and surgical care vs. primary care clinic) were independently associated with higher risk of surgical intervention. CONCLUSION: LDH compromises military readiness and negatively impacts healthcare costs. MHS beneficiaries with LDH have a good prognosis with approximately 88% of patients successfully completing conservative management. However, strategies to improve outcomes of conservative management in LDH should address risks associated with both patient and facility characteristics.Level of Evidence: 4.

Disparities in inpatient costs and outcomes after elective anterior cervical discectomy and fusion at safety-net hospitals.

INTRODUCTION: Characterizing disparities that exist at safety-net hospitals is crucial for crafting national healthcare reform policies. Healthcare disparities in performing elective neurosurgical procedures like anterior cervical discectomy and fusion (ACDF) at safety-net hospitals have not yet been examined. OBJECTIVE: We use the National Inpatient Sample (NIS), a national all-payer healthcare database of inpatient admissions, to determine whether safety-net hospitals can provide equitable care after elective ACDF. METHODS: The NIS from 2002 to 2011 was queried for patients who received ACDF in the context of degenerative spine disease. Hospital safety-net burden was designated as low (LBH), medium (MBH), or high (HBH) based on the proportion of inpatient admissions that were billed as Medicaid, self-pay, or charity care. Significance was set at p < 0.001. RESULTS: A total of 219,433 admissions were included in this analysis. HBHs were more likely than LBHs to treat patients who were Black, Hispanic, on Medicaid, or had myelopathy (p < 0.001). After adjusting for patient, hospital, and clinical factors, treatment at an HBH was associated with greater in-patient inflation-adjusted log cost (p < 0.001), but not with greater length of stay (LOS) (p = 0.04) or odds of an inpatient adverse event like death, incidental durotomy, surgical site infections, deep vein thromboses and others (OR 95 % CI = 0.86-1.42, p = 0.43) compared to LBHs. DISCUSSION: Safety net hospitals had greater inpatient costs, but no greater LOS or odds of inpatient adverse events after elective ACDF. These results demonstrate a need for policies that reduce the cost of performing ACDFs at SNHs.

Association Between Physician Industry Payments and Cost of Anterior Cervical Discectomy and Fusion in Medicare Beneficiaries.

BACKGROUND: Neurosurgical spine specialists receive considerable amounts of industry support that may impact the cost of care. The aim of this study was to evaluate the association between industry payments received by spine surgeons and the total hospital and operating room (OR) costs of an anterior cervical discectomy and fusion (ACDF) procedure among Medicare beneficiaries. METHODS: All ACDF cases were identified among the Medicare carrier files from January 1, 2013, to December 31, 2014, and matched to the Medicare inpatient baseline file. The total hospital and OR charges were obtained for these cases. Charges were converted to cost using year-specific cost-to-charge ratios. Surgeons were identified among the Open Payments database, which is used to quantify industry support. Analyses were performed to examine the association between industry payments received and ACDF costs. RESULTS: Matching resulting in the inclusion of 2209 ACDF claims from 2013-2014. In 2013 and 2014, the mean total cost for an ACDF was $21,798 and $21,008, respectively; mean OR cost was $5878 and $6064, respectively. Mann-Whitney U test demonstrated no significant differences in the mean total or OR cost for an ACDF based on quartile of general industry payment received (P = 0.21 and P = 0.54), and linear regression found no association between industry general payments, research support, or investments on the total hospital cost (P = 0.41, P = 0.13, and P = 0.25, respectively), or OR cost for an ACDF (P = 0.35, P = 0.24, and P = 0.40, respectively). CONCLUSIONS: This study suggests that spine surgeons performing ACDF surgeries may receive industry support without impacting the cost of care.

Later Surgical Start Time Is Associated With Longer Length of Stay and Higher Cost in Cervical Spine Surgery.

STUDY DESIGN: Retrospective study of a surgical cohort from a single, large academic institution. OBJECTIVE: The aim of this study was to investigate associations between surgical start time, length of stay, cost, perioperative outcomes, and readmission. SUMMARY OF BACKGROUND DATA: One retrospective study with a smaller cohort investigated associations between surgical start time and outcomes in spine surgery and found that early start times were correlated with shorter length of stay. No examinations of perioperative outcomes or cost have been performed. METHODS: All patients undergoing anterior cervical discectomy and fusion (ACDF) and posterior cervical decompression and fusion (PCDF) were queried from a single institution from January 1, 2008 to November 30, 2016. Patients undergoing surgery that started between 12:00 AM and 6:00 AM were excluded due to their likely emergent nature. Cases starting before and after 2:00 PM were compared on the basis of length of stay and cost as the primary outcomes using multivariable logistic regression. RESULT: The patients undergoing ACDF and PCDF were both similar on the basis of comorbidity burden, preoperative diagnosis, and number of segments fused. The patients undergoing ACDF starting after 2 PM had longer LOS values (adjusted difference of 0.65 days; 95% confidence interval [CI]: 0.28-1.03; P = 0.0006) and higher costs of hospitalization (adjusted difference of $1177; 95% CI: $549-$1806; P = 0.0002). Patients undergoing PCDF starting after 2 PM also had longer LOS values (adjusted difference of 1.19 days; 95% CI: 0.46-1.91; P = 0.001) and higher costs of hospitalization (adjusted difference of $2305; 95% CI: $826-$3785; P = 0.002). CONCLUSION: Later surgical start time is associated with longer LOS and higher cost. These findings should be further confirmed in the spine surgical literature to investigate surgical start time as a potential cost-saving measure. LEVEL OF EVIDENCE: 3.

Disparities in Outcomes by Insurance Payer Groups for Patients Undergoing Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective, observational study of clinical outcomes at a single institution. OBJECTIVE: To compare postoperative complication and readmission rates of payer groups in a cohort of patients undergoing anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: Studies examining associations between primary payer and outcomes in spine surgery have been equivocal. METHODS: Patients at Mount Sinai having undergone ACDF from 2008 to 2016 were queried and assigned to one of five insurance categories: uninsured, managed care, commercial indemnity insurance, Medicare, and Medicaid, with patients in the commercial indemnity group serving as the reference cohort. Multivariable logistic regression equations for various outcomes with the exposure of payer were created, controlling for age, sex, American Society of Anesthesiology Physical Status Classification (ASA Class), the Elixhauser Comorbidity Index, and number of segments fused. A Bonferroni correction was utilized, such that alpha = 0.0125. RESULTS: Two thousand three hundred eighty seven patients underwent ACDF during the time period. Both Medicare (P < 0.0001) and Medicaid (P < 0.0001) patients had higher comorbidity burdens than commercial patients when examining ASA Class. Managed care (2.86 vs. 2.72, P = 0.0009) and Medicare patients (2.99 vs. 2.72, P < 0.0001) had more segments fused on average than commercial patients. Medicaid patients had higher rates of prolonged extubation (odds ratio [OR]: 4.99; 95% confidence interval [CI]: 1.13-22.0; P = 0.007), and Medicare patients had higher rates of prolonged length of stay (LOS) (OR: 2.44, 95% CI: 1.13-5.27%, P = 0.004) than the commercial patients. Medicaid patients had higher rates of 30- (OR: 4.12; 95% CI: 1.43-11.93; P = 0.0009) and 90-day (OR: 3.28; 95% CI: 1.34-8.03; P = 0.0009) Emergency Department (ED) visits than the commercial patients, and managed care patients had higher rates of 30-day readmission (OR: 3.41; 95% CI: 1.00-11.57; P = 0.0123). CONCLUSION: Medicare and Medicaid patients had higher rates of prolonged LOS and postoperative ED visits, respectively, compared with commercial patients. LEVEL OF EVIDENCE: 3.

Ninety-Day Bundled Payment Reimbursement for Patients Undergoing Anterior and Posterior Procedures for Degenerative Cervical Radiculopathy.

BACKGROUND: Anterior cervical discectomy with fusion (ACDF) or posterior cervical foraminotomy (PCF) are the mainstay surgical treatment options for patients with degenerative cervical radiculopathy (DCR). OBJECTIVE: To compare 90-d bundled payments between ACDF and PCF for DCR in a cohort study. METHODS: Data were extracted from MarketScan database (2000-2016) using ICD-9, ICD-10, and CPT-4 codes. The bundle payments were calculated as the payments accumulated from the index hospitalization admission to 90 d postsurgery. We also analyzed the index hospitalization (physician, hospital, and total) and the postdischarge payments (hospital readmission, outpatient services, medications, and total). Surgical groups were matched based on baseline characteristics (age, sex, insurance type, and Elixhauser score). RESULTS: A total of 100 041 patients met the inclusion criteria. 94.9% of patients (n = 95 031). Patients underwent ACDF with 5.1% (n = 5 010) treated via PCF. Overall, median 90-d costs were significantly higher for ACDF than for PCF ($31567 vs $18412; P < .0001). The median total index hospitalization ($27841 vs $15043), physician ($4572 vs $1920), and hospital payments ($14540 vs $7404) were higher for ACDF compared to PCF for both single- and multiple-level cohorts (P < .0001). There was no difference in overall 90-d postdischarge payments. Factors associated with higher 90-d payments for both cohorts included age and comorbidity scores. CONCLUSION: ACDF is associated with greater bundle payments in patients diagnosed with DCR. No difference was noted for the total postdischarge payments. PCF may be a cost-effective surgical option in appropriately selected patients with unilateral, paracentral, and foraminal soft herniated discs.

National Trends in the Surgical Management of Lumbar Spinal Stenosis in Adult Spinal Deformity Patients.

STUDY DESIGN: This is a retrospective analysis of national administrative hospital data. OBJECTIVE: This study examines national trends in the surgical management of lumbar spinal stenosis (LSS) in patients with and without coexisting scoliosis between 2010 and 2014. The study also examines revision rates for LSS procedures. SUMMARY OF BACKGROUND DATA: There is wide variability in the surgical management of patients with LSS, with and without coexisting spinal deformity. METHODS: Data were obtained from the Healthcare Cost and Utilization Project's National Inpatient Sample Database. International Classification of Diseases 9th revision- Clinical Modification codes were used to identify all patients with a primary diagnosis of lumbar spinal stenosis. These patients were divided into two groups: 1) LSS alone and 2) LSS with coexisting scoliosis. The two groups were examined for one of three surgical outcomes: 1) decompression alone (discectomy, laminectomy), 2) simple fusion, and 3) complex fusion (>three vertebrae or 360° fusion). The groups were then further examined for revision operations. National Inpatient Sample discharge weights were applied where relevant. RESULTS: In 2014 national estimates of discharged patients indicated 76,275 patients with a primary diagnosis of LSS (population rate, 23.9; in the elderly (65+) the age-adjusted population rate was 95.4). Of these patients, 88.5% were managed through primary surgery (34.6% decompression, 47.2% simple fusion, 5.7% complex fusion). Between 2010 and 2014, the percentage of decompression decreased from 47.5% to 34.6%, the percent of simple fusion increased from 35.3% to 47.2%, and the percent of complex fusion increased from 5.7% to 7.1% (P < 0.01). In patients with coexisting scoliosis, lumbar spinal stenosis was predominantly managed by simple fusion and complex fusion (15.5% decompression, 51.9% simple fusion, 27.3% complex fusion, in 2014). Revision rates were highest among patients without scoliosis managed with complex fusion (15.8% in 2014) compared with patients with scoliosis (8.8% in 2014). Patients with scoliosis who underwent decompression only had revision rates of 1.7% and 0.62% in 2010 and 2014, respectively. CONCLUSION: We observed a leveling-off of the rate of operation for patients with a primary diagnosis of LSS at around 88%. There was an increase in the rate of fusion and a decrease in the rate of decompression across all patient groups. We report no difference in revision rates between patients with and without scoliosis, except in those undergoing a complex fusion. LEVEL OF EVIDENCE: 3.

What Are the Costs of Cervical Radiculopathy Prior to Surgical Treatment?

STUDY DESIGN: Retrospective, observational study. OBJECTIVE: To examine the costs associated with nonoperative management (diagnosis and treatment) of cervical radiculopathy in the year prior to anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: While the costs of operative treatment have been previously described, less is known about nonoperative management costs of cervical radiculopathy leading up to surgery. METHODS: The Humana claims dataset (2007-2015) was queried to identify adult patients with cervical radiculopathy that underwent ACDF. Outcome endpoint was assessment of cumulative and per-capita costs for nonoperative diagnostic (x-rays, computed tomographic [CT], magnetic resonance imaging [MRI], electromyogram/nerve conduction studies [EMG/NCS]) and treatment modalities (injections, physical therapy [PT], braces, medications, chiropractic services) in the year preceding surgical intervention. RESULTS: Overall 12,514 patients (52% female) with cervical radiculopathy underwent ACDF. Cumulative costs and per-capita costs for nonoperative management, during the year prior to ACDF was $14.3 million and $1143, respectively. All patients underwent at least one diagnostic test (MRI: 86.7%; x-ray: 57.5%; CT: 35.2%) while 73.3% patients received a nonoperative treatment. Diagnostic testing comprised of over 62% of total nonoperative costs ($8.9 million) with MRI constituting the highest total relative spend ($5.3 million; per-capita: $489) followed by CT ($2.6 million; per-capita: $606), x-rays ($0.54 million; per-capita: $76), and EMG/NCS ($0.39 million; per-capita: $467). Conservative treatments comprised of 37.7% of the total nonoperative costs ($5.4 million) with injections costs constituting the highest relative spend ($3.01 million; per-capita: $988) followed by PT ($1.13 million; per-capita: $510) and medications (narcotics: $0.51 million, per-capita $101; gabapentin: $0.21 million, per-capita $93; NSAIDs: 0.107 million, per-capita $47), bracing ($0.25 million; per-capita: $193), and chiropractic services ($0.137 million; per-capita: $193). CONCLUSION: The study quantifies the cumulative and per-capital costs incurred 1-year prior to ACDF in patients with cervical radiculopathy for nonoperative diagnostic and treatment modalities. Approximately two-thirds of the costs associated with cervical radiculopathy are from diagnostic modalities. As institutions begin entering into bundled payments for cervical spine disease, understanding condition specific costs is a critical first step. LEVEL OF EVIDENCE: 3.

Trends and Costs of Anterior Cervical Discectomy and Fusion: a Comparison of Inpatient And Outpatient Procedures.

Study Design: Epidemiologic Study. Objectives: To identify the trends in utilization of outpatient discharge for single level anterior cervical discectomy and fusion (ACDF), between 2007 and 2014, and to compare the costs and incidence of complications against a cohort of inpatients. Methods: We retrospectively reviewed 18,386 patients from the PearlDiver database from between 2007 and 2014. Discharge status was determined from billing codes. The total cost of all procedures and diagnostic tests, was determined for the global period from the time of diagnosis up until 90-days post-operatively, and the incidence of complications was recorded for 30-days. Results: The proportion of outpatient discharges was stable around 20% from 2007 to 2014 (range17-23%). The mean 90-day cost was lower for outpatients ($39,528 v. $47,330) but reimbursement fell nearly 1/3 from 2007-2014 for both groups, and the difference between the two narrowed over time ($13,745 difference in 2008, to $3,834 in 2014). Outpatients had a lower incidence of overall 30-day complications (9.5% v. 18.6%, p<0.0001), but were also significantly less comorbid (mean Charlson comorbidity index 2.32 v. 3.85, p<0.001). Older patient age, obesity, cardiac, renal, and pulmonary comorbidity were each more common in the inpatients (p<0.05 for each). Conclusions: Outpatient discharge after ACDF is a viable treatment option with a reasonable safety profile and decreased costs relative to inpatient admission. Appropriate patient selection is key, and the standard of care nationally for the comorbid patient remains inpatient admission. The economic trends and epidemiologic data presented here should be useful for health policy decisions.

Outpatient spine surgery: defining the outcomes, value, and barriers to implementation.

Spine surgery is a key target for cost reduction within the United States health care system. One possible strategy involves the transition of inpatient surgeries to the ambulatory setting. Lumbar laminectomy with or without discectomy, lumbar fusion, anterior cervical discectomy and fusion, and cervical disc arthroplasty all represent promising candidates for outpatient surgeries in select populations. In this focused review, the authors clarify the different definitions used in studies describing outpatient spine surgery. They also discuss the body of evidence supporting each of these procedures and summarize the proposed cost savings. Finally, they examine several patient- and surgeon-specific considerations to highlight the barriers in translating outpatient spine surgery into actual practice.

Propensity-matched comparison of outcomes and cost after macroscopic and microscopic lumbar discectomy using a national longitudinal database.

OBJECTIVE There has been considerable debate about the utility of the operating microscope in lumbar discectomy and its effect on outcomes and cost. METHODS A commercially available longitudinal database was used to identify patients undergoing discectomy with or without use of a microscope between 2007 and 2015. Propensity matching was performed to normalize differences between demographics and comorbidities in the 2 cohorts. Outcomes, complications, and cost were subsequently analyzed using bivariate analysis. RESULTS A total of 42,025 patients were identified for the "macroscopic" group, while 11,172 patients were identified for the "microscopic" group. For the propensity-matched analysis, the 11,172 patients in the microscopic discectomy group were compared with a group of 22,340 matched patients who underwent macroscopic discectomy. There were no significant differences in postoperative complications between the groups other than a higher proportion of deep vein thrombosis (DVT) in the macroscopic discectomy cohort versus the microscopic discectomy group (0.4% vs 0.2%, matched OR 0.48 [95% CI 0.26-0.82], p = 0.0045). Length of stay was significantly longer in the macroscopic group compared to the microscopic group (mean 2.13 vs 1.83 days, p < 0.0001). Macroscopic discectomy patients had a higher rate of revision surgery when compared to microscopic discectomy patients (OR 0.92 [95% CI 0.84-1.00], p = 0.0366). Hospital charges were higher in the macroscopic discectomy group (mean $19,490 vs $14,921, p < 0.0001). CONCLUSIONS The present study suggests that the use of the operating microscope in lumbar discectomy is associated with decreased length of stay, lower DVT rate, lower reoperation rate, and decreased overall hospital costs.

A comparison of a self-locking stand-alone cage and anterior cervical plate for ACDF: Minimum 3-year assessment of radiographic and clinical outcomes.

OBJECTIVES: The self-locking stand-alone cage has been clinically applied in treating cervical degenerative disc disease (CDDD). However, no long-term clinical and radiographic studies have been performed so far. This retrospective study was designed to analyze and compare the efficacy and outcomes of anterior cervical discectomy and fusion (ACDF) using self-locking stand-alone cages and cages with the anterior cervical plating system. PATIENTS AND METHODS: A total of 98 consecutive patients were recruited in this study. Patients in the cage group were given stand-alone self-locking cages, and patients in the plate group were treated with cages and anterior plate fixation. The operative time, intraoperative blood loss and complications were recorded. Clinical outcomes were evaluated using the JOA scoring system, Neck Disability Index and Odom's criteria. The cervical lordosis, subsidence and cervical fusion status were assessed by X-ray and computed tomography. RESULTS: The mean follow-up period was 39.7 months in the cage group and 42.2 months in the plate group. The operative time, intraoperative blood loss, postoperative dysphagia, sore throat and adjacent segment degeneration in the cage group were significantly less than those in the plate group (p < 0.05). All the patients in both groups achieved complete interbody fusion. Postoperative JOA and NDI scores in both groups were obviously improved compared with the preoperative ones. The postoperative cervical lordosis was effectively restored in both groups. CONCLUSIONS: The self-locking stand-alone cage for ACDF could effectively restore the cervical physiological curvature, cause few complications, and lead to satisfactory outcomes. Therefore, it could be used as an effective and reliable treatment for the CDDD.

Intersurgeon Cost Variability in Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective review of prospective patient outcomes and cost data. OBJECTIVE: To analyze the contribution of surgeon-specific variability in cost and patient-reported outcomes (PROs) to overall variability in anterior cervical discectomy and fusion (ACDF), whereas adjusting for patient comorbidities. SUMMARY OF BACKGROUND DATA: Cost reduction in surgical care has received increased attention. Patient factors contributing to cost variability in ACDF have been described; however, intersurgeon cost and outcome variability has received less attention in the literature. METHODS: Adult patients undergoing elective primary ACDF by five different surgeons were analyzed from a prospective registry database. Direct and indirect 90-day costs were compared across each surgeon, along with PROs. Predicted costs were calculated based on patient co-morbidities, and an "observed versus expected" cost differential was measured for each surgeon; this O/E cost ratio was then compared with PROs. RESULTS: A total of 431 patients were included in the analysis. There were no differences in comorbidities, age, smoking status, or narcotic use. There was significant variation between surgeons in total 90-day costs, as well as variation between each surgeon's observed versus expected cost ratio. Despite these surgeon-specific cost variations, there were no differences in PROs across the participating surgeons. CONCLUSION: Intersurgeon cost variation in elective ACDF persists even after adjusting for patient comorbidities. There was no apparent correlation between increased surgeon-specific costs and 90-day PROs. These findings show there is opportunity for improvement in inter-surgeon cost variation without compromise in PROs. LEVEL OF EVIDENCE: 3.

Preoperative Opioid Use is a Predictor of Poor Return to Work in Workers' Compensation Patients After Lumbar Diskectomy.

STUDY DESIGN: A retrospective cohort. OBJECTIVE: The aim of this study was to determine the impact of preoperative opioid use in workers' compensation (WC) patients undergoing lumbar diskectomy (LD). SUMMARY OF BACKGROUND DATA: The prevalence of back pain among opioid users approached 60%. Long-term opioid dependence in spine surgery patients is roughly 20%. Despite pervasive use, there is no evidence to support long-term opioid analgesic use for back pain. METHODS: Ten thousand five hundred ninety-two patients received compensation from the Ohio Bureau of Workers' Compensation for a lumbar disc herniation between 2005 and 2012. Patients with spine comorbidities, smoking history, or multilevel surgery were excluded. Preoperatively, 566 patients had no opioid use, 126 had short-term opioid use (STO), 315 had moderate opioid use (MTO), and 279 had long-term opioid use (LTO). The primary outcome was whether subjects returned to work (RTW). RESULTS: Seven hundred twelve (55.4%) patients met our RTW criteria. There was a significant difference in RTW rates among the no opioid (64.1%), MTO (52.7%), and LTO (36.9%) populations. Multivariate logistic regression analysis found several covariates to be independent negative predictors of RTW status: preoperative opioid use [P < 0.01; odds ratio (OR) = 0.54], time to surgery (P < 0.01; OR = 0.98 per month), legal representation (P < 0.01; OR = 0.57), and psychiatric comorbidity (P = 0.02; OR = 0.36). Patients in the LTO group had higher medical costs (P < 0.01), rates of psychiatric comorbidity (P < 0.01), incidence of failed back surgery syndrome (FBSS) (P < 0.01), and postoperative opioid use (P < 0.01) compared with the STO and no opioid groups. CONCLUSION: Preoperative opioid use was determined to be a negative predictor of RTW rates after LD in WC patients. In addition, long-term preoperative opioid use was associated with higher medical costs, psychiatric illness, FBSS, and postoperative opioid use. Even a short or moderate course of preoperative opioids was associated with worse outcomes compared with no use. For WC patients undergoing LD, judicious use of preoperative opioid analgesics may improve clinical outcomes and reduce the opioid burden. LEVEL OF EVIDENCE: 3.

Is Two-level Cervical Disc Replacement More Cost-effective Than Anterior Cervical Discectomy and Fusion at 7 Years?

STUDY DESIGN: Cost-effectiveness analysis. OBJECTIVE: To investigate 7-years cost-effectiveness of two-level cervical disc replacement (CDR) and anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: CDR and ACDF are both effective treatment strategies for managing degenerative conditions of the cervical spine. CDR has been shown to be a more-cost effective intervention in the short term, but the long-term cost-effectiveness has not been established. METHODS: We analyzed 7-years follow-up data from the two-level Medtronic Prestige LP investigational device exemption study. Short-form 36 (SF-36) data were converted into health utility scores using the SF-6D algorithm. Costs were based on direct costs from the payer perspective, and effectiveness was measured as quality-adjusted life years (QALYs). The willingness-to-pay (WTP) threshold was set to $50,000/QALY. A probabilistic sensitivity analysis was conducted via Monte Carlo simulation. RESULTS: Two-level CDR had a 7-year cost of $176,654.19, generated 4.65 QALYs, and had a cost-effectiveness ratio of $37,993.53/QALY. Two-level ACDF had a 7-year cost of $158,373.48, generated 4.44 QALYs, and had a cost-effectiveness ratio of $35,635.72. CDR was associated with an incremental cost of $18,280.71 and an incremental effectiveness of 0.21 QALYs, resulting in an incremental cost-effectiveness ratio (ICER) of $89,021.04, above the WTP threshold. Our Monte Carlo simulation demonstrated CDR would be chosen 46% of the time based on 10,000 simulations. CONCLUSION: Two-level CDR and ACDF are both cost-effective procedures at 7-year follow up for treating degenerative conditions of the cervical spine. Based on an ICER of $89,021.04/QALY, we cannot conclude which treatment is the more cost-effective option at 7-years. CDR would be chosen 46% of the time based on 10,000 iterations of our Monte Carlo probabilistic sensitivity analysis. LEVEL OF EVIDENCE: 3.

Trends in resource utilization and rate of cervical disc arthroplasty and anterior cervical discectomy and fusion throughout the United States from 2006 to 2013.

BACKGROUND CONTEXT: The typically accepted surgical procedure for cervical disc pathology has been the anterior cervical discectomy and fusion (ACDF), although recent trials have demonstrated equivalent or improved outcomes with cervical disc arthroplasty (CDA). Trends for these two procedures regarding utilization, revision procedures, and other demographic information have not been sufficiently explored. PURPOSE: The present study aims to provide data regarding ACDF and CDA from 2006 to 2013 in the United States. DESIGN: The present study is a retrospective national database analysis. PATIENT SAMPLE: The present study included 20% sample of discharges from US hospitals, which is weighted to provide national estimates. OUTCOME MEASURES: Functional measures such as national incidence, hospital costs, length of stay (LOS), routine discharge, revision burden, and patient characteristics were used in the present study. METHODS: Patients from the National Inpatient Sample (NIS) database who underwent primary ACDF, revision ACDF, primary CDA, and revision CDA from 2006 to 2013 were included. Demographic and economic data for the procedures' respective International Classification of Diseases, Ninth Revision, Clinical Modification codes were collected. RESULTS: A total of 1,059,403 ACDF and 13,099 CDA surgeries were performed in the United States from 2006 to 2013. The annual number of ACDF increased by 5.7% nonlinearly from 120,617 in 2006 to 127,500 in 2013 (mean per year 132,425; range 120,617-147,966); CDA increased by 190% nonlinearly from 540 in 2006 to 1,565 in 2013 (mean per year 1,637; range 540-2,381). Cervical disc arthroplasty patients were younger and had more private or "other" insurance, including worker's compensation (p<.0001). Mean LOS was longer for ACDF (ACDF 2.3 days vs. CDA 1.5; p<.0001). Routine discharge was higher in the CDA group (CDA 96% vs. ACDF 89%; p-value<.0001). The mean hospital-related cost was more expensive for ACDF (ACDF $16,178 vs. CDA $13,197; p-value=.0007). Cervical disc arthroplasty mean revision burden, defined as the ratio of revision procedures to the sum of primary and revision procedures, was greater (CDA 5.9% vs. ACDF 2.3%, p-value=.01). CONCLUSIONS: Nationally approximately 132,000 ACDFs are done each year compared with only 1,600 CDAs. The number of ACDF surgeries performed far outpaces CDA by a ratio of 81:1 in the United States without a clear direction in the trend for utilization given recent fluctuations. Cervical disc arthroplasty revision burden was more than double compared with the ACDF revision burden (5.9% vs. 2.3%), which was not accounted for by patient baseline demographics. The etiologies of these findings are likely multifactorial and require further research.

Increased Volume of Lumbar Surgeries for Herniated Intervertebral Disc Disease and Cost-Effectiveness Analysis: A Nationwide Cohort Study.

STUDY DESIGN: Retrospective cohort study of a nationwide database. OBJECTIVE: The primary objective was to summarize the use of surgical methods for lumbar herniated intervertebral disc disease (HIVD) at two different time periods under the national health insurance system. The secondary objective was to perform a cost-effectiveness analysis by utilizing incremental cost-effectiveness ratio (ICER). SUMMARY OF BACKGROUND DATA: The selection of surgical method for HIVD may or may not be consistent with cost effectiveness under national health insurance system, but this issue has rarely been analyzed. METHODS: The data of all patients who underwent surgeries for HIVD in 2003 (n = 17,997) and 2008 (n = 38,264) were retrieved. The surgical methods included open discectomy (OD), fusion surgery, laminectomy, and percutaneous endoscopic lumbar discectomy (PELD). The hospitals were classified as tertiary-referral hospitals (≥300 beds), medium-sized hospitals (30-300 beds), or clinics (<30 beds). ICER showed the difference in the mean total cost per 1% decrease in the reoperation probability among surgical methods. The total cost included the costs of the index surgery and the reoperation. RESULTS: In 2008, the number of surgeries increased by 2.13-fold. The number of hospitals increased by 34.75% (731 in 2003 and 985 in 2008). The proportion of medium-sized hospitals increased from 62.79% to 70.86%, but the proportion of surgeries performed at those hospitals increased from 61.31% to 85.08%. The probability of reoperation was highest after laminectomy (10.77%), followed by OD (10.50%), PELD (9.20%), and fusion surgery (7.56%). The ICERs indicated that PELD was a cost-effective surgical method. The proportion of OD increased from 71.21% to 84.12%, but that of PELD decreased from 16.68% to 4.57%. CONCLUSION: The choice of surgical method might not always be consistent with cost-effectiveness strategies, and a high proportion of medium-sized hospitals may be responsible for this change. LEVEL OF EVIDENCE: 4.