Cost-effectiveness of Operative versus Nonoperative Treatment of Adult Symptomatic Lumbar Scoliosis an Intent-to-treat Analysis at 5-year Follow-up.

STUDY DESIGN: Secondary analysis using data from the NIH-sponsored study on adult symptomatic lumbar scoliosis (ASLS) that included randomized and observational arms. OBJECTIVE: The aim of this study was to perform an intent-to-treat cost-effectiveness study comparing operative (Op) versus nonoperative (NonOp) care for ASLS. SUMMARY OF BACKGROUND DATA: The appropriate treatment approach for ASLS continues to be ill-defined. NonOp care has not been shown to improve outcomes. Surgical treatment has been shown to improve outcomes, but is costly with high revision rates. METHODS: Patients with at least 5-year follow-up data were included. Data collected every 3 months included use of NonOp modalities, medications, and employment status. Costs for index and revision surgeries and NonOp modalities were determined using Medicare Allowable rates. Medication costs were determined using the RedBook and indirect costs were calculated based on reported employment status and income. Qualityadjusted life year (QALY) was determined using the SF6D. RESULTS: There were 81 of 95 cases in the Op and 81 of 95 in the NonOp group with complete 5-year follow-up data. Not all patients were eligible 5-year follow-up at the time of the analysis. All patients in the Op and 24 (30%) in the NonOp group had surgery by 5 years. At 5 years, the cumulative cost for Op was $96,000 with a QALY gain of 2.44 and for NonOp the cumulative cost was $49,546 with a QALY gain of 0.75 with an incremental cost-effectiveness ratio (ICER) of $27,480 per QALY gain. CONCLUSION: In an intent-to-treat analysis, neither treatment was dominant, as the greater gains in QALY in the surgery group come at a greater cost. The ICER for Op compared to NonOp treatment was above the threshold generally considered cost-effective in the first 3 years of the study but improved over time and was highly cost-effective at 4 and 5 years. LEVEL OF EVIDENCE: 2.

The Berg balance scale for assessing dynamic stability and balance in the adult spinal deformity (ASD) population.

BACKGROUND: Adult spinal deformity (ASD) is a prevalent condition in individuals over the age of 65; leading to impaired standing balance and abnormal gait patterns. This functional impairment may be due to the fixed sagittal or coronal malalignment; associated spinal stenosis or deconditioning. The Berg balance scale (BBS) was developed to measure balance by assessing the performance of functional tasks. The purpose of this study is to determine if BBS is a useful metric for evaluating functional status in ASD patients. METHODS: ASD patients who required fusion from the thoracic spine to the pelvis from 2014 to 2016 were enrolled and asked to complete the BBS prior to and six months after surgery. BBS were obtained by a certified physical therapist. Standard demographic; radiographic and surgical data were collected. The Oswestry disability index (ODI), EuroQOL-5D and numeric rating scales (0 to 10) for back and leg pain were assessed at baseline and post-intervention. RESULTS: Of 21 patients enrolled; 19 completed pre- and post-surgery BBS. The mean age was 59.8±13.3 years with 14 females. There was a statistically significant improvement in all outcome scores and radiographic parameters after surgery; but no difference in BBS. Only one patient had a BBS score low enough to be considered a medium fall risk. There was no difference in the pre-op BBS scores in the four patients that had revision surgery compared to those that did not. CONCLUSIONS: In this small pilot study; BBS did not appear to be associated with measures of clinical and radiographic improvement in ASD patients. The test was also potentially problematic in that it has a ceiling effect and required significant time with a trained physical therapist for administration. Continued effort to identify a viable measure of balance dysfunction in ASD patients is warranted.

Outcomes and revision rates following multilevel anterior cervical discectomy and fusion.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) for cervical degenerative disease is an accepted treatment for symptomatic cervical radiculopathy and myelopathy. One- and two-level fusions are much more common and more widely studied. Outcomes and revision rates for three- and four-level ACDF have not been well described. The purpose of this study is to report on clinical outcomes and revision rates following multilevel ACDF. METHODS: Patients who underwent three- or four-level anterior cervical discectomy with plate fixation between 2006 and 2011 from a single-center multi-surgeon practice for symptomatic cervical degenerative disease were identified. Improvements in neck disability index (NDI), neck and arm pain scores two years after surgery and revision rates were analyzed. RESULTS: Forty-six patients with a mean age of 55.9 years were included in the analysis. Twenty-one (46%) were male, 10 (22%) were smokers. Forty-one (89%) underwent three-level fusion and 5 (11%) underwent four-level fusion. NDI improved from 34.46 at baseline to 25.47 at 2 years. Neck pain improved from 7.04 at baseline to 3.95 and arm pain improved from 6.24 to 3.09 at 2 year follow up. Sixteen patients (35%) returned to surgery within 2 years with 11 of these patients (24%) returning for non-union. The average number of days to revision surgery was 750.6±570.3 days. CONCLUSIONS: Patients undergoing three- and four-level ACDF for multilevel cervical disease demonstrate substantial improvement in outcomes. However, the two-year revision rate is relatively high at 35% with the majority of these patients returning due to non-union.

Randomized trial of Cell Saver in 2- to 3-level lumbar instrumented posterior fusions.

OBJECTIVEThe goal of this study was to determine efficacy and cost-effectiveness of Cell Saver in 2- and 3-level lumbar decompression and fusion.METHODSPatients seen at a tertiary care spine center who were undergoing a posterior 2- or 3-level lumbar decompression and fusion were randomized to have Cell Saver used during their surgery (CS group, n = 48) or not used (No Cell Saver [NCS] group, n = 47). Data regarding preoperative and postoperative hemoglobin and hematocrit, estimated blood loss, volume of Cell Saver blood reinfused, number of units and volume of allogeneic blood transfused intraoperatively and postoperatively, complications, and costs were collected. Costs associated with Cell Saver use were calculated based on units of allogeneic blood transfusions averted.RESULTSDemographics and surgical parameters were similar in both groups. The mean estimated blood loss was similar in both groups: 612 ml in the CS group and 742 ml in the NCS group. There were 53 U of allogeneic blood transfused in 29 patients in the NCS group at a total blood product cost of $67,688; and 38 U of allogeneic blood transfused in 16 patients in the CS group at a total blood cost of $113,162, resulting in a cost of $3031 per allogeneic blood transfusion averted using Cell Saver.CONCLUSIONSCell Saver use produced lower rates of allogeneic transfusion but was found to be more expensive than using only allogeneic blood for 2- and 3-level lumbar degenerative fusions. This increased cost may be reasonable to patients who perceive that the risks associated with allogeneic transfusions are unacceptable.■ CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: randomized controlled trial; evidence: class III.

Cost-effectiveness of Lumbar Epidural Steroid Injections.

STUDY DESIGN: Longitudinal cohort. OBJECTIVE: To determine the cost per quality-adjusted life-year for lumbar epidural steroid injections (LESI). SUMMARY OF BACKGROUND DATA: Despite being a widely performed procedure, there are few studies evaluating the cost-effectiveness of LESIs. METHODS: Patients who had received LESI between June 2012 and July 2013 with EuroQOL-5D (EQ-5D) scores available before and after LESIs but before any surgical intervention were identified. Costs were calculated on the basis of the Medicare Fee Schedule multiplied by the number of LESIs received between the 2 clinic visits. Quality-adjusted life-years (QALYs) were calculated using the EQ-5D. RESULTS: Of 421 patients who had pre-LESI EQ-5D data, 323 (77%) had post-LESI data available; 200 females, 123 males, mean age: 59.2 ±â€Š14.2 years. Cost per LESI was $608, with most patients receiving 3 LESIs for more than 1 year (range: 1-6 yr). Mean QALY gained was 0.005. One hundred forty-five patients (45%) had a QALY gain (mean = 0.117) at a cost of $62,175 per QALY gained; 127 patients (40%) had a loss in QALY (mean = -0.120) and 51 patients (15%) had no change in QALY. Fourteen of the 145 patients who improved, and 29 of the 178 patients who did not, have medical comorbidities that precluded surgery. Thirty-two (22%) of 131 patients without medical comorbidities who improved and 57 (32%) of 149 patients without medical comorbidities who did not improve subsequently had undergone surgery (P = 0.015). CONCLUSION: LESI may not be cost-effective in patients with lumbar degenerative disorders. For the 145 patients who improved, cost per QALY gained was acceptable at $62,175. However, for the 178 patients with no gain or a loss in QALY, the economics are not reportable with a cost per QALY gained being theoretically infinite. Further studies are needed to identify specific patient populations who will benefit from LESI because the economic viability of LESI requires improved patient selection. LEVEL OF EVIDENCE: 2.

Outcomes and revision rates in normal, overweight, and obese patients 5 years after lumbar fusion.

BACKGROUND CONTEXT: Obesity is a growing problem in health care. Studies have demonstrated similar functional outcomes but higher complication rates after spine surgery in obese patients. PURPOSE: This study aimed to compare patient-reported outcomes and revision rates 5 years after instrumented posterior lumbar fusion between normal, overweight, and obese patients. STUDY DESIGN: Propensity matched case control. PATIENT SAMPLE: Patients who had posterior instrumented lumbar spinal fusion from 2001 to 2008 from a single spine specialty center with complete preoperative and 5-year postoperative outcome measures were identified. OUTCOME MEASURES: Oswestry Disability Index (ODI), Back Pain (0-10) and Leg Pain (0-10) Numeric Rating Scales, and Short Form-36 Physical Composite Summary Scores (SF-36 PCS). METHODS: Three comparison groups, one with body mass index (BMI) ≥20-25 kg/m2 (normal), another with ≥25-<30 kg/m2 (overweight), and another with ≥30-40 kg/m2 (obese) were created using propensity matching techniques based on demographics, baseline clinical outcome measures, and surgical characteristics. Five-year postoperative outcome measures and revision rates in the three groups were compared. One-way analysis of variance was used to compare continuous variables, and Fisher exact test was used to compare categorical variables between the groups. Significance was set at p<.01. RESULTS: There were 82 cases matched in each cohort. Estimated blood loss (440 cc vs. 702 cc vs. 798 cc, p=.000) and operative time (234 minutes vs. 263 minutes vs. 275 minutes, p=.003) were significantly greater in the overweight and obese patients. Improvements in ODI (14.2 vs. 9.6 vs. 10.4, p=.226), SF-36 PCS (5.9 vs. 2.9 vs. 3.5, p=.361), back pain (3.0 vs. 2.0 vs. 2.1, p=.028), and leg pain (3.0 vs. 2.3 vs. 2.3, p=.311) scores were similar among the groups. Revision rates (14 vs. 15 vs. 13, p=.917), and time between index and revision surgery (p=.990) were similar among the three groups as well. CONCLUSION: When considering a subset of patient-reported outcomes and revision surgery after 5 years, patients with an elevated BMI >25 at baseline did not appear to have worse outcomes than those with a normal BMI of 20-25 when undergoing posterior lumbar fusion surgery. Obesity should not be considered a contraindication to surgery in patients with appropriate surgical indications.

Can the anxiety domain of EQ-5D and mental health items from SF-36 help predict outcomes after surgery for lumbar degenerative disorders?

OBJECTIVE Studies have shown that anxious or depressed patients may have poorer outcomes after lumbar fusion. These conclusions were drawn from questionnaires specifically designed to measure anxiety and depression. The objective of this study is to determine if responses to the EQ-5D anxiety/depression domain or the items used to calculate the 36-Item Short-Form Health Survey (SF-36) Mental Component Summary (MCS) can predict outcomes after lumbar fusion surgery. METHODS Patients enrolled in the National Neurosurgery Quality and Outcomes Database from a single center with 1-year follow-up were identified. The outcomes collected include the Oswestry Disability Index (ODI), EQ-5D, SF-36, and the back- and leg-pain numeric rating scales (range 0-10). Linear regression modeling was performed to predict the 1-year ODI scores using the EQ-5D anxiety/depression domain and the 14 items used to calculate SF-36 MCS. RESULTS Complete data were available for 312 (88%) of 353 eligible patients. The mean patient age was 58.5 years, 175 (56%) patients were women, and 52 patients were smokers. After controlling for other factors, the item in the SF-36 that asks "Have you felt downhearted and depressed?" is the strongest predictor of the 1-year ODI score (r(2) = 0.191; p = 0.000) and 1-year EQ-5D score (r(2) = 0.205; p = 0.000). Neither the EQ-5D anxiety/depression domain nor the diagnoses of anxiety or depression were predictors of 1-year outcomes. CONCLUSIONS Patient responses to SF-36 item "Have you felt downhearted and depressed?" account for 20% of the variability of the 1-year ODI and EQ-5D scores and can be used by clinicians to screen for anxiety or depression in patients prior to lumbar fusion surgery. Clinicians may offer psychological support to these patients preoperatively in order to improve treatment outcomes.

Estimating EQ-5D values from the Neck Disability Index and numeric rating scales for neck and arm pain.

OBJECT: The Neck Disability Index (NDI) and numeric rating scales (0 to 10) for neck pain and arm pain are widely used cervical spine disease-specific measures. Recent studies have shown that there is a strong relationship between the SF-6D and the NDI such that using a simple linear regression allows for the estimation of an SF-6D value from the NDI alone. Due to ease of administration and scoring, the EQ-5D is increasingly being used as a measure of utility in the clinical setting. The purpose of this study is to determine if the EQ-5D values can be estimated from commonly available cervical spine disease-specific health-related quality of life measures, much like the SF-6D. METHODS: The EQ-5D, NDI, neck pain score, and arm pain score were prospectively collected in 3732 patients who presented to the authors' clinic with degenerative cervical spine disorders. Correlation coefficients for paired observations from multiple time points between the NDI, neck pain and arm pain scores, and EQ-5D were determined. Regression models were built to estimate the EQ-5D values from the NDI, neck pain, and arm pain scores. RESULTS: The mean age of the 3732 patients was 53.3 ± 12.2 years, and 43% were male. Correlations between the EQ-5D and the NDI, neck pain score, and arm pain score were statistically significant (p < 0.0001), with correlation coefficients of -0.77, -0.62, and -0.50, respectively. The regression equation 0.98947 + (-0.00705 × NDI) + (-0.00875 × arm pain score) + (-0.00877 × neck pain score) to predict EQ-5D had an R-square of 0.62 and a root mean square error (RMSE) of 0.146. The model using NDI alone had an R-square of 0.59 and a RMSE of 0.150. The model using the individual NDI items had an R-square of 0.46 and an RMSE of 0.172. The correlation coefficient between the observed and estimated EQ-5D scores was 0.79. There was no statistically significant difference between the actual EQ-5D score (0.603 ± 0.235) and the estimated EQ-5D score (0.603 ± 0.185) using the NDI, neck pain score, and arm pain score regression model. However, rounding off the coefficients to fewer than 5 decimal places produced less accurate results. CONCLUSIONS: The regression model estimating the EQ-5D from the NDI, neck pain score, and arm pain score accounted for 60% of the variability of the EQ-5D with a relatively large RMSE. This regression model may not be sufficient to accurately or reliably estimate actual EQ-5D values.

Estimating EQ-5D values from the Oswestry Disability Index and numeric rating scales for back and leg pain.

STUDY DESIGN: Cross-sectional cohort. OBJECTIVE: The purpose of this study is to determine whether the EuroQOL-5D (EQ-5D) can be derived from commonly available low back disease-specific health-related quality of life measures. SUMMARY OF BACKGROUND DATA: The Oswestry Disability Index (ODI) and numeric rating scales (0-10) for back pain (BP) and leg pain (LP) are widely used disease-specific measures in patients with lumbar degenerative disorders. Increasingly, the EQ-5D is being used as a measure of utility due to ease of administration and scoring. METHODS: The EQ-5D, ODI, BP, and LP were prospectively collected in 14,544 patients seen in clinic for lumbar degenerative disorders. Pearson correlation coefficients for paired observations from multiple time points between ODI, BP, LP, and EQ-5D were determined. Regression modeling was done to compute the EQ-5D score from the ODI, BP, and LP. RESULTS: The mean age was 53.3 ± 16.4 years and 41% were male. Correlations between the EQ-5D and the ODI, BP, and LP were statistically significant (P < 0.0001) with correlation coefficients of -0.77, -0.50, and -0.57, respectively. The regression equation: [0.97711 + (-0.00687 × ODI) + (-0.01488 × LP) + (-0.01008 × BP)] to predict EQ-5D, had an R2 of 0.61 and a root mean square error of 0.149. The model using ODI alone had an R2 of 0.57 and a root mean square error of 0.156. The model using the individual ODI items had an R2 of 0.64 and a root mean square error of 0.143. The correlation coefficient between the observed and estimated EQ-5D score was 0.78. There was no statistically significant difference between the actual EQ-5D (0.553 ± 0.238) and the estimated EQ-5D score (0.553 ± 0.186) using the ODI, BP, and LP regression model. However, rounding off the coefficients to less than 5 decimal places produced less accurate results. CONCLUSION: Unlike previous studies showing a robust relationship between low back-specific measures and the Short Form-6D, a similar relationship was not seen between the ODI, BP, LP, and the EQ-5D. Thus, the EQ-5D cannot be accurately estimated from the ODI, BP, and LP. LEVEL OF EVIDENCE: 2.

The discriminative properties of the SF-6D compared with the SF-36 and ODI.

STUDY DESIGN: Longitudinal cohort. OBJECTIVES: To determine the discriminate validity of the Short Form-6D (SF-6D) compared with the SF-36 in a cohort of patients with lumbar degenerative disorders. SUMMARY OF BACKGROUND DATA: Cost-utility studies are important for the demonstration of comparative effectiveness of treatments for lumbar degenerative disorders. Multidimensional patient-reported outcome tools including the SF-36 and Oswestry Disability Index (ODI) may be limited to measuring the utility of specific health care states. The evaluation of utility is based on single-index preference-based health state scales, such as the SF-6D. The loss of discriminative properties using a single-index compared with a multidimensional score is unknown. METHODS: The cohort studies included 1104 patients who had decompression and lumbar fusion with complete ODI, SF-36, and SF-6D data at baseline and 2-year follow-up. Discriminative properties of the 3 measures were compared by computing the effect size (ES) and the standardized response mean (SRM). The larger the ES and SRM, the more sensitive to change the measure is. The relative validity (RV) statistic for each measure was also determined with the SF-6D as reference. Measures that are more sensitive than the SF-6D would have RVs greater than 1.0, those that are less sensitive would have RVs less than 1.0. RESULTS: The ODI had the greatest ES at 0.93 followed by the SF-6D at 0.88 and the SF-36 Physical Composite Score (PCS) at 0.85. The ODI also had the greatest standardized response mean at 0.73 followed by the SF-6D at 0.70 and the SF-36 PCS at 0.57. The RV statistics for both the ODI (1.28) and the SF-36 PCS (1.32) were greater compared with the SF-6D. The SF-36 bodily pain domain had the greatest ES (1.42), SRM (0.81), and RV (1.50). The general health domain had the lowest ES (0.21) and SRM (0.23), whereas mental health domain had the lowest RV. CONCLUSIONS: In this cohort of patients, using the single-index SF-6D produces a loss of discriminative properties compared with the SF-36 and ODI. However, this loss is small, because all the effect sizes remain large (≥0.80). Therefore, these losses should not preclude the use of the SF-6D compared with the SF-36 and may be preferred because it is more easily interpretable and less difficult to incorporate in economic evaluations.

Blood salvage produces higher total blood product costs in single-level lumbar spine surgery.

STUDY DESIGN: Retrospective review. OBJECTIVE: To determine the incremental cost-effectiveness of cell saver for single-level posterior lumbar decompression and fusion (PLDF). SUMMARY OF BACKGROUND DATA: Intraoperative cell salvage is used during surgery to reduce the need for perioperative allogeneic blood transfusion. Although the use of cell saver may be beneficial in certain circumstances, its utility has not been clearly established for the common procedure of an adult single-level PLDF. METHODS: Randomly selected adult patients treated with a single-level PLDF between July 2010 and June 2011 at a single institution were identified. Patients who had a combined anterior and posterior approach were excluded. The final study sample for analysis consisted of 180 patients. Hospital records were reviewed to determine whether: (1) cell saver was available during surgery, (2) recovered autologous blood was infused, and (3) the patient received intra- or postoperative allogeneic transfusions. Estimated blood loss, levels fused, volume(s) transfused, and all related complications were recorded. Costs included the cost of allogeneic blood transfusion, setting up the cell saver recovery system, and infusing autologous blood from cell saver, whereas effectiveness measures were allogeneic blood transfusions averted and quality adjusted life years. RESULTS: The incremental cost-effectiveness ratio was $55,538 per allogeneic transfusion averted, with a decrease in the transfusion rate from 40.0% to 38.7% associated with the cell saver approach. This translated into an incremental cost-effectiveness ratio of $5,555,380 per quality adjusted life years gained, which is well above the threshold for an intervention to be considered cost-effective ($100,000 per quality adjusted life years gained). CONCLUSION: The use of cell saver during a single-level PLDF does not significantly reduce the need for allogeneic blood transfusion and is not cost-effective. The high cost of cell saver in combination with the low complication rate of allogeneic blood transfusion, suggest that cell saver should not be used for single-level PLDF. Further studies are needed to evaluate the necessity for cell saver among other types of spinal surgery.

Predictive factors for the use of autologous cell saver transfusion in lumbar spinal surgery.

STUDY DESIGN: Retrospective review. OBJECTIVE: To identify risk factors for cell saver transfusion in lumbar spinal surgery and determine if cell saver transfusions affected intraoperative or postoperative transfusion rates. SUMMARY OF BACKGROUND DATA: Cell saver has been used to minimize allogeneic blood transfusion in lumbar spinal surgery. Conflicting reports exist, which call into question the efficacy of cell saver use. METHODS: We reviewed medical records of randomly selected patients who underwent posterolateral fusion with or without transforaminal interbody fusion from July 2010 to June 2011. Transfusion rates and transfusion-related complications were determined. Binary logistic regression was performed to identify risk factors for use of autologous cell saver transfusion. RESULTS: There were 178 females and 107 males, with a mean age of 57.2 years. Of the 285 cases, 39 had no cell saver available, 147 had cell saver available but no autologous blood was recovered or transfused and 99 had an autologous cell saver transfusion. Patients who had cell saver transfusion had a higher rate of intraoperative allogeneic blood transfusion (52%) compared with those who did not (22%). There was no significant difference in the rate of postoperative transfusions or transfusion-related reactions between patients who did and did not have cell saver transfusion. Patient's age, smoking status, American Society of Anesthesiologists grade, use of anticoagulants preoperatively, primary or revision surgery, iliac crest bone graft harvest, anesthesiologist, or surgeon had no significant effect on cell saver infusion. Body mass index (odds ratio [OR] = 1.06), number of posterolateral fusion levels fused (OR = 2.50), and number of transforaminal interbody fusions performed (OR = 2.41) were independent risk factors for the use of autologous cell saver transfusion. CONCLUSION: Body mass index, multi-level fusion and transforaminal interbody fusion result in increased use of autologous cell saver transfusion in lumbar spinal surgery. Use of autologous cell saver transfusion did not reduce the requirement for intraoperative or postoperative allogeneic blood transfusion. LEVEL OF EVIDENCE: 2.

Differentiating minimum clinically important difference for primary and revision lumbar fusion surgeries.

OBJECT: Previous studies have reported on the minimum clinically important difference (MCID), a threshold of improvement that is clinically relevant for lumbar degenerative disorders. Recent studies have shown that pre- and postoperative health-related quality of life (HRQOL) measures vary among patients with different diagnostic etiologies. There is also concern that a patient's previous care experience may affect his or her perception of clinical improvement. This study determined if MCID values for the Oswestry Disability Index (ODI), 36-Item Short-Form Health Survey (SF-36), and back and leg pain are different between patients undergoing primary or revision lumbar fusion. METHODS: Prospectively collected preoperative and 1-year postoperative patient-reported HRQOLs, including the ODI, SF-36 physical component summary (PCS), and numeric rating scales (0-10) for back and leg pain, in patients undergoing lumbar spine fusion were analyzed. Patients were grouped into either the primary surgery or revision group. As the most widely accepted MCID values were calculated from the minimum detectable change, this method was used to determine the MCID. RESULTS: A total of 722 patients underwent primary procedures and 333 patients underwent revisions. There was no statistically significant difference in demographics between the groups. Each group had a statistically significant improvement at 1 year postoperatively compared with baseline. The minimum detectable change-derived MCID values for the primary group were 1.16 for back pain, 1.36 for leg pain, 12.40 for ODI, and 5.21 for SF-36 PCS. The MCID values for the revision group were 1.21 for back pain, 1.28 for leg pain, 11.79 for ODI, and 4.90 for SF-36 PCS. These values are very similar to those previously reported in the literature. CONCLUSIONS: The MCID values were similar for the revision and primary lumbar fusion groups, even when subgroup analysis was done for different diagnostic etiologies, simplifying interpretation of clinical improvement. The results of this study further validate the use of patient-reported HRQOLs to measure clinical effectiveness, as a patient's previous experience with care does not seem to substantially alter an individual's perception of clinical improvement.

Changes in the Oswestry Disability Index that predict improvement after lumbar fusion.

OBJECT: Clinical studies use both disease-specific and generic health outcomes measures. Disease-specific measures focus on health domains most relevant to the clinical population, while generic measures assess overall health-related quality of life. There is little information about which domains of the Oswestry Disability Index (ODI) are most important in determining improvement in overall health-related quality of life, as measured by the 36-Item Short Form Health Survey (SF-36), after lumbar spinal fusion. The objective of the study is to determine which clinical elements assessed by the ODI most influence improvement of overall health-related quality of life. METHODS: A single tertiary spine center database was used to identify patients undergoing lumbar fusion for standard degenerative indications. Patients with complete preoperative and 2-year outcomes measures were included. Pearson correlation was used to assess the relationship between improvement in each item of the ODI with improvement in the SF-36 physical component summary (PCS) score, as well as achievement of the SF-36 PCS minimum clinically important difference (MCID). Multivariate regression modeling was used to examine which items of the ODI best predicted achievement for the SF-36 PCS MCID. The effect size and standardized response mean were calculated for each of the items of the ODI. RESULTS: A total of 1104 patients met inclusion criteria (674 female and 430 male patients). The mean age at surgery was 57 years. All items of the ODI showed significant correlations with the change in SF-36 PCS score and achievement of MCID for the SF-36 PCS, but only pain intensity, walking, and social life had r values > 0.4 reflecting moderate correlation. These 3 variables were also the dimensions that were independent predictors of the SF-36 PCS, and they were the only dimensions that had effect sizes and standardized response means that were moderate to large. CONCLUSIONS: Of the health dimensions measured by the ODI, pain intensity, walking, and social life best predicted improvement in overall health-related quality of life, as measured using the SF-36 PCS.

The influence of preoperative MRI findings on lumbar fusion clinical outcomes.

INTRODUCTION: Spinal fusion as a treatment for degenerative disc disease is controversial. Prior authors have identified various MRI findings as being pain generators, which might help guide patient selection for lumbar fusion procedures. These findings have included disc desiccation, disc contour, high-intensity zone annular disruption, the presence of Modic endplate changes, and disc space collapse. The purpose of this study is to investigate which MRI findings in patients with degenerative disc disease predict clinical improvement with lumbar fusion. METHODS: A single-center surgical database of patients undergoing lumbar fusion was reviewed for patients whose indication for fusion surgery was primary disc pathology. We identified 51 patients (71 disc levels) who had completed 2-year prospectively collected outcomes questionnaires and had preoperative MRIs available for review. NRS (0-10) back and leg pain, Oswestry Disability Index (ODI) and SF-36 Physical Composite Summary scores were obtained preoperatively and at 1- and 2-year follow-up. MRIs were reviewed by three fellowship-trained spine surgeons who were asked to grade them for the following five characteristics: (a) disc desiccation, (b) disc contour, (c) presence of a high-intensity zone (HIZ) annular tear, (d) presence of Modic endplate changes and (e) disc height. Two-year outcome measures were compared to MRI findings to identify which findings correlated with improvement in outcome scores. RESULTS: Statistically significant improvements were noted in back pain, leg pain, SF-36 PCS and ODI in the group overall. Disc desiccation, disc contour, presence of an HIZ lesion, and the presence of Modic endplate changes did not correlate with 2-year outcomes. Disc height was correlated with 2-year change in outcome measures. Discs with preoperative height less than 5 mm demonstrated a 23.4 point ODI improvement compared to 9.2 points for discs >7 mm. Similarly, SF-36 PCS improved 9.5 points in discs <5 mm compared to 0.7 in discs greater than 7 mm. Discs between 5 and 7 mm demonstrated intermediate levels of improvement. CONCLUSIONS: Several commonly utilized MRI criteria proposed as indications for lumbar fusion do not seem to correlate with 2-year improvement in clinical outcomes. Discs which are narrowed and collapsed, preoperatively, demonstrate better improvement at 2 years postoperatively as compared to discs which have maintained disc height. Significant disc space collapse may represent a subset of "degenerative disc disease" which responds more favorably to treatment with fusion.

Inter- and intraobserver reliability in radiographic assessment of degenerative disk disease.

Clinicians use descriptive classification systems when treating patients with low back pain as an adjunct to surgical decision making. Magnetic resonance imaging (MRI) changes, including Modic changes, the presence of a high-intensity zone, and internal disk desiccation, are commonly used descriptors. The question remains whether different clinicians interpret these terms similarly. This study evaluated the inter- and intraobserver reliability of commonly used MRI classifications in patients presenting with low back pain.Sixty-six patients who underwent lumbar spine fusion surgery at a single multiphysician spine specialty practice for degenerative disk disease were identified. For each surgical level, the following MRI variables were determined independently by 3 fellowship-trained spine surgeons: presence or absence of high-intensity zone and/or internal disk desiccation, presence and classification of disk herniation, Modic grade, and disk height. Each surgeon reviewed the same set of MRI studies a second time at least 2 weeks from the first reading. Inter- and intraobserver reliability was determined using multiobserver Kappa coefficients. Intraobserver reliability ranged from 0.563 to 0.988, with greatest agreement in determining disk height. The greatest interobserver agreement was for determining Modic changes (0.819).Controversy remains on the criteria for diagnosing degenerative disk disease. In patients presenting with low back pain diagnosed with degenerative disk disease, the inter- and intraobserver reliability with use of several common MRI diagnostic tools was substantial. These data imply that clinicians interpret these findings in a reproducible fashion and interpret these terms similarly.

Spinal appearance questionnaire: factor analysis, scoring, reliability, and validity testing.

STUDY DESIGN: Cross sectional. OBJECTIVE: This study presents the factor analysis of the Spinal Appearance Questionnaire (SAQ) and its psychometric properties. SUMMARY OF BACKGROUND DATA: Although the SAQ has been administered to a large sample of patients with adolescent idiopathic scoliosis (AIS) treated surgically, its psychometric properties have not been fully evaluated. This study presents the factor analysis and scoring of the SAQ and evaluates its psychometric properties. METHODS: The SAQ and the Scoliosis Research Society-22 (SRS-22) were administered to AIS patients who were being observed, braced or scheduled for surgery. Standard demographic data and radiographic measures including Lenke type and curve magnitude were also collected. RESULTS: Of the 1802 patients, 83% were female; with a mean age of 14.8 years and mean initial Cobb angle of 55.8° (range, 0°-123°). From the 32 items of the SAQ, 15 loaded on two factors with consistent and significant correlations across all Lenke types. There is an Appearance (items 1-10) and an Expectations factor (items 12-15). Responses are summed giving a range of 5 to 50 for the Appearance domain and 5 to 20 for the Expectations domain. The Cronbach's α was 0.88 for both domains and Total score with a test-retest reliability of 0.81 for Appearance and 0.91 for Expectations. Correlations with major curve magnitude were higher for the SAQ Appearance and SAQ Total scores compared to correlations between the SRS Appearance and SRS Total scores. The SAQ and SRS-22 Scores were statistically significantly different in patients who were scheduled for surgery compared to those who were observed or braced. CONCLUSION: The SAQ is a valid measure of self-image in patients with AIS with greater correlation to curve magnitude than SRS Appearance and Total score. It also discriminates between patients who require surgery from those who do not.

Instrumented open-door laminoplasty as treatment for cervical myelopathy in 104 patients.

Treatment of multilevel cervical myelopathy remains a challenge. We report on a large series of cervical myelopathy patients treated with instrumented open-door laminoplasty. We retrospectively examined the medical records of 104 patients who had undergone instrumented open-door laminoplasty (titanium plate) for cervical myelopathy (minimum follow-up, 24 months). All patients had been myelopathic, 57 (54.8%) had stenosis, 39 (37.5%) had spondylosis, 66 (63.5%) reported gait disturbance, 18 (17.3%) had handwriting changes, 33 (31.7%) complained of deterioration of dexterity, 56 (53.8%) had grasp weakness, 7 (6.7%) had bowel and bladder complaints, 27 (26.0%) had a positive Hoffmann sign, 10 (9.6%) had sustained clonus, and 10 (9.6%) had a positive Babinski sign. Mean preoperative-to-postoperative improvement in Nurick grade was 1.47. Complications included 4 nerve root injuries (3.8%), 1 of which (at C5) was permanent, and 1 transient neurologic deterioration (<1%), 1 incidental durotomy (<1%), and 5 wound infections (4.8%). Four patients required anterior revision for persistent symptoms. Open-door laminoplasty with miniplate instrumentation is an effective, safe method for preventing progression of myelopathy with multilevel involvement while alleviating the need for multilevel fusion.

Identification and surgical treatment of primary thoracic spinal stenosis.

We report the surgical treatment results for 7 patients (4 men, 3 women; mean age, 49 years) who presented with myelopathy caused exclusively by primary thoracic spinal stenosis, predominantly in the lower thoracic spine. (Patients with concurrent ascending lumbosacral degenerative disease were excluded.) All patients received extensive nonoperative treatment before referral to our center. Surgical treatment consisted of wide posterior decompression and instrumented fusion (5 cases), anterior vertebrectomy and fusion (1), and anterior vertebrectomy with autograft strut followed by wide posterior decompression and instrumented fusion (1). Mean operative time was 313 minutes, mean blood loss was 944 mL, and there were no major postoperative complications. Minimum follow-up was 2 years. Five patients had significant improvement in myelopathy and were ambulating normally, 1 had modest improvement in ambulation, and 1 remained wheelchair-bound. All patients achieved solid radiographic fusions. After presenting these case studies, we review the current literature on treatment effectiveness. Primary thoracic spinal stenosis should be considered in patients who present with isolated lower extremity myelopathy, particularly when no significant pathologic findings are identified in the cervical or lumbosacral spine. Expedient wide decompression with concurrent instrumented fusion is recommended to prevent late development of spinal instability and recurrent spinal stenosis.