Journal of Neurosurgery: Spine
Sean M. Jones-Quaidoo, Mladen Djurasovic, R. Kirk Owens II and Leah Y. Carreon
Recent studies have reported the incidence of superior facet joint violation using percutaneous techniques. These techniques have not been compared with the open midline approach. An increased incidence of superior facet violation may lead to adjacent-segment disease. In this paper, the authors' goal is to compare the rate of superior facet violation with the use of percutaneously placed pedicle screws versus midline approach open placement.
Patients who underwent a single-level fusion using a percutaneous approach from L-1 to S-1 who had undergone CT scanning within 1 year after surgery were identified. A cohort who underwent open fusion matched by level of surgery was identified. All CT scans were reviewed by 3 fellowship-trained spine surgeons to determine the degree of facet violation. The final categorization for each screw was based on the most frequent reading among the 6 evaluations. The Fisher test was used to determine the association of facet violation with approach.
There were 66 patients in each group. Patients in the Percutaneous group were younger (mean 42.5 years) than those in the Open group (mean 57.8 years, p = 0.000). There was no statistically significant difference in sex distribution, surgical levels fused, or time between surgery and CT scan between the groups. Thirty-six (13.6%) of 264 screws in the percutaneous and 16 (6%) of 263 screws in the Open group were in the facet joint (p = 0.005). Of these, 17 (12%) of the 132 proximal screws in the percutaneous and 7 (5%) of the 131 proximal screws in the Open group were in the facet joint (p = 0.052).
The use of a percutaneous method to insert pedicle screws results in a statistically significantly higher incidence of facet joint violation, even if only proximal screws are considered. Further studies are needed to determine if this leads to a higher incidence of symptomatic adjacent-level disease.
Leah Y. Carreon, Kelly R. Bratcher, Chelsea E. Canan, Lauren O. Burke, Mladen Djurasovic and Steven D. Glassman
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.
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.
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.
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.
Mladen Djurasovic, Steven D. Glassman, John R. Dimar II, Charles H. Crawford III, Kelly R. Bratcher and Leah Y. Carreon
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.
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.
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.
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.
Mladen Djurasovic, Katlyn E. McGraw, Kelly Bratcher, Charles H. Crawford III, John R. Dimar II, Rolando M. Puno, Steven D. Glassman, R. Kirk Owens II and Leah Y. Carreon
The goal of this study was to determine efficacy and cost-effectiveness of Cell Saver in 2- and 3-level lumbar decompression and fusion.
Patients 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.
Demographics 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.
Cell 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.
Leah Y. Carreon, Mladen Djurasovic, John R. Dimar II, R. Kirk Owens II, Charles H. Crawford III, Rolando M. Puno, Kelly R. Bratcher, Katlyn E. McGraw and Steven D. Glassman
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.
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.
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 (r2 = 0.191; p = 0.000) and 1-year EQ-5D score (r2 = 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.
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.