Surgical Treatment of Single-Level Lumbar Stenosis Is Associated with Lower 2-Year Mortality and Total Cost Compared with Nonsurgical Treatment: A Risk-Adjusted, Paired Analysis.

BACKGROUND: Spine surgery has demonstrated cost-effectiveness in reducing pain and restoring function, but the impact of spine surgery relative to nonsurgical care on longer-term outcomes has been less well described. Our objective was to compare single-level surgical treatment for lumbar stenosis, with or without spondylolisthesis, and nonsurgical treatment with respect to patient mortality, resource utilization, and health-care payments over the first 2 years following initial treatment. METHODS: A retrospective review of the Medicare National Database Fee for Service Files from 2011 to 2017 was performed. A 2-year prediction of mortality risk (risk stratification index, RSI) was used as a measure of patient baseline health. Patients (88%) were matched by RSI and demographics. Mortality, spine-related health-care utilization, and 2-year total Medicare payments for patients undergoing surgical treatment were compared with matched patients undergoing nonsurgical treatment. RESULTS: We identified 61,534 patients with stenosis alone and 83,813 with stenosis and spondylolisthesis. Surgical treatment was associated with 28% lower 2-year mortality compared with matched patients undergoing nonsurgical treatment. Total Medicare payments were significantly lower for patients with stenosis alone undergoing laminectomy alone and for patients with stenosis and spondylolisthesis undergoing laminectomy with or without fusion compared with patients undergoing nonsurgical treatment. There was no significant difference in mortality when fusion or laminectomy was compared with combined fusion and laminectomy. However, laminectomy alone was associated with significantly lower 2-year payments when treating stenosis with or without spondylolisthesis. CONCLUSIONS: Surgical treatment for stenosis with or without spondylolisthesis within the Medicare population was associated with significantly lower mortality and total medical payments at 2 years compared with nonsurgical treatment, although residual confounding could have contributed to these findings. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

High-Volume Arthroplasty Centers Demonstrate Higher Composite Quality Scores and Enhanced Value: Perspective on Higher-Volume Hospitals Performing Arthroplasty from 2001 to 2011.

BACKGROUND: In recent years, there has been a move toward value-based health care. Value is generally defined as outcome divided by cost; however, it is not clear exactly how to define and measure outcomes. In this study, we utilized the Nationwide Inpatient Sample (NIS) to determine how hospital volume and other factors affect quality for patients undergoing total hip and knee arthroplasty. METHODS: Using the NIS of the Healthcare Cost and Utilization Project (HCUP) of the Agency for Healthcare Research and Quality (AHRQ), we conducted a retrospective study of all total hip and total knee arthroplasties performed from 2001 to 2011. We identified all procedure and outcome variables using the International Classification of Diseases, Ninth Revision (ICD-9) billing codes. Patients were grouped into quartiles based on the corresponding hospital's procedure volume. The quality measurement for each hospitalization was binary, with perfect inpatient care reflecting a favorable result for all of the following outcomes of interest: death, sepsis, postoperative infection, thromboembolic events, venous thrombosis, hematoma, blood transfusion, and length of stay below average. The Perfect Inpatient Care Index (PICI) was then calculated for each hospital. The PICI was defined as the number of hospitalizations with no unfavorable outcomes divided by total volume of arthroplasty. Value was measured as the PICI divided by the mean total charges. Multivariable nested regression was used to determine variables that predict perfect inpatient care. RESULTS: From 2001 to 2011, the NIS database reported 1,651,354 total hip or total knee arthroplasties. Hospital arthroplasty volume ranged from 0 to 11,758 procedures. Overall, hospital PICI scores increased as arthroplasty volume increased. In multivariable nested regression analysis, procedure volume (odds ratio [OR] for the highest quartile compared with the lowest quartile, 2.116 [95% confidence interval (CI), 1.883 to 2.378]) and lower patient acuity (OR, 2.450 [95% CI, 2.429 to 2.472]) were independently associated with better PICI scores. Value increased as hospital procedure volume increased. CONCLUSIONS: Hospital procedure volume varied widely. Although small differences were seen in individual outcome measures, composite scores (PICI) and value were substantially better at hospitals that had higher procedure volume and in lower-acuity patients. LEVEL OF EVIDENCE: Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Co-management Strategies for Hospitals and Orthopedic and Neurosurgery Practices.

Co-management arrangements can be a very effective means of aligning physicians and their hospitals to gain care delivery efficiencies, control costs, and reduce variation in practices. In an era of value-based care delivery all aspects must be examined and the appropriate incentives put in place to reduce waste and optimize asset and resource utilization. This article will review legal considerations, define basic co-management structure and goals, and suggest examples of metrics used to achieve success.

Polymorphic variation of the guanosine triphosphate cyclohydrolase 1 gene predicts outcome in patients undergoing surgical treatment for lumbar degenerative disc disease.

STUDY DESIGN: Prospective observational study. OBJECTIVE: To determine whether polymorphic variations of the guanosine triphosphate (GTP) cyclohydrolase 1 gene (GCH1) are associated with different outcomes in patients undergoing surgical treatment for lumbar degenerative disc disease (DDD). SUMMARY OF BACKGROUND DATA: GCH1, the gene encoding the rate-limiting enzyme in tetrahydrobiopterin synthesis, has been strongly implicated as a determinant of pain experience in previous animal and human studies. METHODS.: A total of 69 patients undergoing surgical treatment for lumbar DDD were prospectively enrolled. Genomic DNA was extracted from a venous blood sample, and DNA sequence analysis was performed of GCH1. Surgery included 65 instrumented fusions and 4 disc arthroplasty procedures. Patients were observed prospectively for 1 year following surgery. Allelic and genotype frequencies were calculated for each of 14 single nucleotide polymorphisms (SNPs). One-year postoperative Oswestry Disability Index (ODI) scores were compared to preoperative scores and the absolute change in ODI score was used to perform genetic association analyses on the basis of both individual SNP markers as well as commonly observed haplotypes for the entire gene sequence. RESULTS: Single marker analysis revealed 1 SNP (rs998259; minor allele T) that was significantly associated with improvement in both absolute ODI score (P = 0.030) and Numerical Rating Scale back pain scores (P = 0.033) following surgery. Haplotype analysis identified a common GCH1 haplotype ("CACTTGTTTGAC") with a sample frequency of 12.3%, which was highly associated with improvement in absolute ODI score (P = 0.04). This haplotype frequency reflects the existence of both heterozygous and homozygous individuals in the study population. The presence of 1 unit of this haplotype was associated with an improvement in postoperative ODI score of 15.34 relative to the absence of this haplotype (P = 0.04). CONCLUSION: Preliminary results from this pilot genetic study of patients undergoing surgery for DDD suggests that the T allele at rs998259 of GCH1 may be associated with improved outcomes 1 year following surgery.

Association of catechol-O-methyltransferase genetic variants with outcome in patients undergoing surgical treatment for lumbar degenerative disc disease.

BACKGROUND CONTEXT: Surgical treatment for lumbar degenerative disc disease (DDD) has been associated with highly variable results in terms of postoperative pain relief and functional improvement. Many experts believe that DDD should be considered a chronic pain disorder as opposed to a degenerative disease. Genetic variation of the catechol-O-methyltransferase (COMT) gene has been associated with variation in human pain sensitivity and response to analgesics in previous studies. PURPOSE: To determine whether genetic variation of COMT is associated with clinical outcome after surgical treatment for DDD. STUDY DESIGN: Prospective genetic association study. PATIENT SAMPLE: Sixty-nine patients undergoing surgical treatment for lumbar DDD. Diagnosis was based on documentation of chronic disabling low back pain (LBP) present for a minimum of 6 months and unresponsive to supervised nonoperative treatment, including activity modification, medication, physical therapy, and/or injection therapy. Plain radiographs and magnetic resonance imaging revealed intervertebral disc desiccation, tears, and/or collapse without focal herniation, nerve root compression, stenosis, spondylolisthesis, spondylolysis, or alternative diagnoses. OUTCOME MEASURES: Oswestry Disability Index (ODI) and visual analog score (VAS) for LBP. METHODS: Surgical treatment included 65 instrumented fusions and four disc arthroplasty procedures. All patients completed preoperative and 1-year postoperative ODI questionnaires. DNA was extracted from a sample of venous blood, and genotype analysis was performed for five common COMT single nucleotide polymorphisms (SNPs). Potential genetic association between these COMT SNPs and the primary outcome variable, 1-year change in ODI, was investigated using both single-marker and haplotype association analyses. Association with VAS scores for LBP was analyzed as a secondary outcome variable. RESULTS: Single-marker analysis revealed that the COMT SNP rs4633 was significantly associated with greater improvement in ODI score 1 year after surgery (p=.03), with individuals homozygous for the less common "T" allele demonstrating the largest improvement in ODI. Haplotype analysis of four COMT SNPs, rs6269, rs4633, rs4818, and rs4680, also identified a common haplotype "ATCA" (haplotype frequency of 39.3% in the study population) associated with greater improvement in ODI (p=.046). The greatest mean improvement in ODI was observed in patients homozygous for the "ATCA"COMT haplotype. A nonsignificant trend was observed between SNP rs4633 and greater improvement in VAS score for LBP. CONCLUSIONS: This is the first study to report an association between surgical treatment success in DDD patients and genetic variation in the putative pain sensitivity gene COMT. These findings require replication in other DDD populations but suggest that genetic testing for pain-relevant genetic markers such as COMT may provide useful clinical information in terms of predicting outcome after surgery for patients diagnosed with DDD.

Prospective study of iliac crest bone graft harvest site pain and morbidity.

BACKGROUND CONTEXT: Morbidity associated with autologous bone graft harvest is an important factor in determining the utility of expensive alternatives such as recombinant bone morphogenic protein. The most frequently reported complication associated with graft harvest is chronic pain. PURPOSE: To prospectively determine the degree of pain and morbidity associated with autologous iliac crest bone graft harvest and its effect on activities of daily living. STUDY DESIGN: Prospective observational cohort study. PATIENT SAMPLE: One hundred ten adult patients undergoing elective posterior lumbar spinal fusion surgery involving autologous iliac crest bone graft harvest. OUTCOME MEASURES: Patient self-reported Visual Analog Scale (VAS) scores for pain and a study-specific questionnaire regarding activities of daily living. METHODS: One hundred ten patients were prospectively enrolled. Postoperative VAS scores (0-100) for harvest site pain were obtained at 6-week, 6- and 12-month follow-up. Patients completed a 12-month questionnaire regarding the persistence of specific symptoms and resulting limitation of specific activities. RESULTS: One hundred four patients were available for 1-year follow-up. Mean VAS pain scores (scale 0-100) at 6 weeks, 6 and 12 months were 22.7 (standard deviation [SD], 25.9), 15.9 (SD, 21.5), and 16.1 (SD, 24.6), respectively. At 12 months, 16.5% reported more severe pain from the harvest site than the primary surgical site, 29.1% reported numbness, and 11.3% found the degree of numbness bothersome, whereas 3.9% were bothered by scar appearance. With respect to activity limitations resulting from harvest site pain at 1 year, 15.1% reported some difficulty walking, 5.2% with employment, 12.9% with recreation, 14.1% with household chores, 7.6% with sexual activity, and 5.9% irritation from clothing. CONCLUSIONS: There is a significant rate of persistent pain and morbidity from iliac crest bone graft harvest when associated with elective spine surgery. Mean pain scores progressively decline over the first postoperative year. Nevertheless, harvest site pain remains functionally limiting in a significant percentage of patients 1 year after surgery. Rates of functional limitation are higher than previously reported and may be because of increased sensitivity of the prospective study design and targeted investigation of these specific symptoms. Validity of these findings is necessarily limited by patient ability to discriminate harvest site pain from alternative sources of back and buttock pain.

Prospective, randomized, multicenter Food and Drug Administration investigational device exemption study of lumbar total disc replacement with the CHARITE artificial disc versus lumbar fusion: five-year follow-up.

BACKGROUND CONTEXT: The CHARITE artificial disc, a lumbar spinal arthroplasty device, was approved by the United States Food and Drug Administration in 2004 based on two-year safety and effectiveness data from a multicenter, prospective, randomized investigational device exemption (IDE) study. No long-term, randomized, prospective study on the CHARITE disc or any other artificial disc has been published to date. PURPOSE: The purpose of this study was to compare the safety and effectiveness at the five-year follow-up time point of lumbar total disc replacement using the CHARITE artificial disc (DePuy Spine, Raynham, MA) with that of anterior lumbar interbody fusion (ALIF) with BAK cages and iliac crest autograft, for the treatment of single-level degenerative disc disease from L4 to S1, unresponsive to nonoperative treatment. STUDY DESIGN/SETTING: Randomized controlled trial-five-year follow-up. PATIENT SAMPLE: Ninety CHARITE patients and 43 BAK patients. OUTCOME MEASURES: Self-reported measures: visual analog scale (VAS); validated Oswestry disability index (ODI version 1.0); Short-Form 36 Questionnaire, and patient satisfaction. Physiologic measures: radiographic range of motion, disc height, and segmental translation. Functional measures: work status. METHODS: Of the 375 subjects enrolled in the CHARITE IDE trial, 277 were eligible for the five-year study and 160 patients thereof completed the five-year follow-up. The completers included 133 randomized patients. Overall success was defined as improvement> or =15 pts in ODI vs. baseline, no device failure, absence of major complications, and maintenance or improvement of neurological status. Additional clinical outcomes included an ODI questionnaire as well as VAS, SF-36, and patient satisfaction surveys. Work status was tracked for all patients. Safety assessments included occurrence and severity of adverse events and device failures. Radiographic analyses such as index- and adjacent-level range of motion, segmental translation, disc height, and longitudinal ossification were also carried out. RESULTS: Overall success was 57.8% in the CHARITE group vs. 51.2% in the BAK group (Blackwelder's test: p=0.0359, Delta=0.10). In addition, mean changes from baseline for ODI (CHARITE: -24.0 pts vs. BAK: -27.5 pts), VAS pain scores (CHARITE: -38.7 vs. BAK: -40.0), and SF-36 questionnaires (SF-36 Physical Component Scores [PCS]: CHARITE: 12.6 pts vs. BAK: 12.3 pts) were similar across groups. In patient satisfaction surveys, 78% of CHARITE patients were satisfied vs. 72% of BAK patients. A total of 65.6% patients in the CHARITE group vs. 46.5% patients in the BAK group were employed full-time. This difference was statistically significant (p=0.0403). Long-term disability was recorded for 8.0% of CHARITE patients and 20.9% of BAK patients, a difference that was also statistically significant (p=0.0441). Additional index-level surgery was performed in 7.7% of CHARITE patients and 16.3% of BAK patients. Radiographic findings included operative and adjacent-level range of motion (ROM), intervertebral disc height and segmental translation. At the five-year follow-up, the mean ROM at the index level was 6.0 degrees for CHARITE patients and 1.0 degrees for BAK patients. Changes in disc height were also similar for both CHARITE and BAK patients (0.7 mm for both groups, p=0.9827). Segmental translation was 0.4 and 0.8mm in patients implanted with CHARITE at L4-L5 vs. L5-S1, respectively, and 0.1mm in BAK patients. CONCLUSIONS: The results of this five-year, prospective, randomized multicenter study are consistent with the two-year reports of noninferiority of CHARITE artificial disc vs. ALIF with BAK and iliac crest autograft. No statistical differences were found in clinical outcomes between groups. In addition, CHARITE patients reached a statistically greater rate of part- and full-time employment and a statistically lower rate of long-term disability, compared with BAK patients. Radiographically, the ROMs at index- and adjacent levels were not statistically different from those observed at two-years postsurgery.

Effect of plate position on clinical outcome after anterior cervical spine surgery.

BACKGROUND CONTEXT: Anterior cervical plates are commonly used to provide immediate stabilization after a variety of cervical spine procedures. It has been assumed that the ideal position for anterior cervical spine plates is centered in the horizontal plane without significant angulation and without overlap of adjacent unfused levels. Nevertheless, postoperative radiographs often demonstrate actual plate position to be lateralized, rotated, or encroaching on the adjacent disc space. There have been no reported systematic studies examining the effect of variations in plate position in a large clinical population. PURPOSE: To evaluate the association between plate position and short-term clinical outcomes after anterior cervical discectomy and instrumented fusion (ACDF). STUDY DESIGN/SETTING: Review of prospectively collected clinical outcomes measures and radiographs. PATIENT SAMPLE: Patients undergoing ACDF surgery by a group of spine surgical specialists at a single institution. OUTCOME MEASURES: Direct and calculated plain radiographic measurements, visual analog scores for neck and arm pain, and SF-36 scores. METHODS: The study population included 200 patients undergoing a one-, two-, or three-level ACDF with instrumentation. Thirteen separate direct measurements and two calculated values of plate position on immediate postoperative radiographs, including lateralization, rotation, and proximity to adjacent disc spaces, were performed in blinded fashion by 3 independent reviewers. Statistical correlation with prospectively collected patient outcomes measures, including VAS for neck and arm pain and SF-36 scores, was performed. RESULTS: In the study population, average plate position was 3.3 mm from the cephalad disc space, 6.4 mm from the caudal disc space, 3.9 degrees angulation in the frontal plate, and 26% laterally displaced from the midline. At average 18.6 months of follow-up, no significant association was identified between any plate position measure and clinical outcomes. CONCLUSIONS: The use of anterior cervical plating by experienced spine surgeons is associated with variation in terms of plate position on postoperative radiographs. Within the range of positions analyzed in this study, no significant association was found between lateralized or rotated plates or plates placed in proximity to adjacent disc spaces and worse short-term clinical outcomes. It should be emphasized that these results and conclusions are based on relatively short-term clinical follow-up and that the long-term effects of variation in implant position remain unknown.

An economic model of one-level lumbar arthroplasty versus fusion.

BACKGROUND CONTEXT: Degenerative disc disease (DDD) is a cause of low back pain commonly requiring surgical intervention. The option of lumbar total disc replacement (TDR) represents an advance in the surgical treatment of DDD. However, new treatments, particularly those that include the use of new implants, may lead to increased costs to both hospitals and payers. Therefore, it is both necessary and appropriate to examine the potential costs associated with a new procedure such as total disc replacement compared with traditional treatments for a specific pathology. PURPOSE: To perform an economic analysis of lumbar TDR versus three different techniques for lumbar fusion. STUDY DESIGN/SETTING: A cost-minimization model. METHODS: An economic model examining hospital and payer cost perspectives was developed to compare costs of TDR with the CHARITE Artificial Disc to three spinal fusion procedures: anterior lumbar interbody fusion (ALIF) with iliac crest bone graft (ICBG); ALIF with INFUSE Bone Graft and LT-Cages, and instrumented posterior lumbar interbody fusion (IPLIF) with ICBG. The hospital perspective compares direct medical costs during the index hospitalization. The payer perspective considers direct medical costs of the index hospitalization and those incurred in the following two-year period. The model contains a Diagnostic Related Group (DRG) arm based strictly on DRG coding and payment, and a per-diem arm that includes a device carve-out cost and payment. RESULTS: In the DRG and per-diem arms of the model, compared with TDR, hospital costs are 12.0% higher for ALIF with ICBG, 36.5% higher for ALIF with INFUSE, and 36.5% higher for IPLIF. For payers, in the per-diem arm compared with TDR, ALIF with ICBG has 4.4% lower cost, whereas ALIF with INFUSE and IPLIF have costs of 16.1% and 27.1% higher, respectively. In the DRG arm compared with TDR, payer cost is 87.1% higher for ALIF with ICBG, 82.8% higher for ALIF with INFUSE, and 99.0% higher for IPLIF. CONCLUSIONS: The model shows that the overall economic effect of one-level TDR procedures on hospitals and payers is likely to be less than or at worse equivalent to one-level lumbar fusion procedures.

The spine service line: optimizing patient-centered spine care.

STUDY DESIGN: Literature review and expert opinion on the delivery of spine care. OBJECTIVE: Our objective was to describe the goals of a spine service line and encourage the implementation of a systems-based approach to spine care. The benefits to patients and institutions are discussed. SUMMARY OF BACKGROUND DATA: Spine care delivery and its associated costs are rising rapidly. There exists tremendous variability in the rate at which it is delivered. With so many options for spine care, patients are subject to decisions of providers with disparate backgrounds and expertise. This leads to inefficiencies in diagnosis and delivery of care. All these factors lead to increased costs of care of uncertain benefit and increased burden to society. METHODS: The literature on systems-based approaches to spine care was reviewed. Those relating to health care policy and recent clinical trials were emphasized. How these data work in a systems-based approach was described. Additionally, the authors' experiences working in and within a structured spine care system were related and included. RESULTS: We describe 3 spine care episodes and where each possesses particular inefficiencies that lead to increased costs without added value to the delivery of spine care. The primary episode is the start of the patient's painful incident. We propose a more uniform guidelines-based approach using appropriate (and similar) diagnostic testing and education. The secondary phase of care can be costly as more sophisticated diagnostic and treatment methods are instituted. Within an institution or spine care practice, matching the level of providers with the patients at this phase of care would lead to better utilization of resources. Additionally, benefits to the institution would be greater if managed properly. The third phase of care focuses on intervention with long-term benefits. We discuss the use of registry like data and analysis of outcomes on these patients. Agreement within a group or institution on operative indications would allow for more uniform analysis of these outcomes. Alternative revenue streams are also discussed. CONCLUSIONS: The patient with spinal disease is in need of high-quality, proven, and efficient care. Using a systems-based approach, we can minimize escalating costs associated with inefficient health care and delivery. Cooperation between physicians and institutions is critical to this process.

Computed tomography evaluation of superior-segment facet-joint violation after pedicle instrumentation of the lumbar spine with a midline surgical approach.

STUDY DESIGN: Retrospective study. OBJECTIVES: To determine the frequency of pedicle screw violation of superior nonfused facet joints adjacent to the most cephalad pedicle screws after a midline approach for lumbar fusion. SUMMARY OF BACKGROUND DATA: Facet-joint violations have been evaluated in patients undergoing lumbar pedicle screw instrumentation and fusion with a Wiltse muscle-splitting approach, but not via the more common midline approach. METHODS: Between 1995 and 2003, 204 patients underwent this procedure. Computed tomography scans (within 1 year postsurgery) were evaluated independently for superior facet-joint violation. chi tests were used to examine bivariate associations of superior level facet-joint violation, patient age, construct level, diagnosis, and revision status for significance (P < or = 0.05). RESULTS: Superior-level facet-joint violation occurred in 24% of patients and 15% of screws, twice as often on the left side (P = 0.0396) than on the right, more frequently in single than in multiple-level procedures (P < 0.0001), and most frequently with the most cephalad screws at L5 (48%). We found no significant associations between violation rates and other designated parameters. CONCLUSION: The left side, single-level fusion, and most cephalad pedicle screws at L5 are targets for interventions to reduce pedicle violations in this procedure.