Utilization trends of pedicle subtraction osteotomies compared to posterior spinal fusion for deformity: A national database analysis between 2008–2011

BACKGROUND: Increased awareness regarding the importance of the sagittal spinal profile has led to more aggressive correction of sagittal malalignment. The utilization trends of pedicle subtraction osteotomy (PSO) for sagittal plane correction in spinal deformity surgery have not been well characterized. METHODS: A commercially available database (PearlDiver, Inc) was queried for both Private Payor and 5 % Medicare claims from 2008 to 2011. Revision and clarification of the coding guidelines for PSO were introduced in 2008. Patients who had a thoracic and/or lumbar PSO were identified using CPT codes (22206-22208). In order to appropriately interpret trends in PSO use, three comparison groups were identified. Patients who had a diagnosis of adult spine deformity were identified using ICD-9 codes. Patients who had fusion for spine deformity or posterior spine fusion were identified using CPT codes. Differences in annual utilization and demographics between these four groups were then compared. RESULTS: From the Private Payor database, 199 PSOs were identified with the number of PSOs increasing from 33 in 2008, to 61 in 2011, representing a 185 % increase. From the Medicare data, 102 PSOs were identified, increasing from 13 in 2008 to 32 in 2011, a 246 % increase. In contrast, from both databases, there was minimal to no increase in the incidence of adult spine deformity, fusion for spine deformity or posterior spine fusion over the study time interval. CONCLUSION: Over the study time interval, there was up to a 3.2-fold increase in the utilization of PSOs while the diagnosis of adult spine deformity, fusion for spine deformity and posterior spine fusions had minimal to no increase

Minimally Invasive Posterior Facet Decortication and Fusion Using Navigated Robotic Guidance: Feasibility and Workflow Optimization

Minimally invasive spine surgery reduces tissue dissection and retraction, decreasing the morbidity associated with traditional open spine surgery by decreasing blood loss, blood transfusion, complications, and pain. One of the key challenges with a minimally invasive approach is achieving consistent posterior fusion. Although advantageous in all fusion surgeries, solid posterior fusion is particularly important in spinal deformity, revisions, and fusions without anterior column support. A minimally invasive surgical approach accomplished without sacrificing the quality of the posterior fusion has the potential to decrease both short- and long-term complications compared to the traditional open techniques. Innovations in navigated and robotic-assisted spine surgery continue to address this need. In this article, we will outline the feasibility of achieving posterior facet fusion using the Mazor X Stealth Edition Robotic Guidance System

Epidural Hematoma Following Cervical Spine Surgery.

STUDY DESIGN: A multicentered retrospective case series. OBJECTIVE: To determine the incidence and circumstances surrounding the development of a symptomatic postoperative epidural hematoma in the cervical spine. METHODS: Patients who underwent cervical spine surgery between January 1, 2005, and December 31, 2011, at 23 institutions were reviewed, and all patients who developed an epidural hematoma were identified. RESULTS: A total of 16 582 cervical spine surgeries were identified, and 15 patients developed a postoperative epidural hematoma, for a total incidence of 0.090%. Substantial variation between institutions was noted, with 11 sites reporting no epidural hematomas, and 1 site reporting an incidence of 0.76%. All patients initially presented with a neurologic deficit. Nine patients had complete resolution of the neurologic deficit after hematoma evacuation; however 2 of the 3 patients (66%) who had a delay in the diagnosis of the epidural hematoma had residual neurologic deficits compared to only 4 of the 12 patients (33%) who had no delay in the diagnosis or treatment (P = .53). Additionally, the patients who experienced a postoperative epidural hematoma did not experience any significant improvement in health-related quality-of-life metrics as a result of the index procedure at final follow-up evaluation. CONCLUSION: This is the largest series to date to analyze the incidence of an epidural hematoma following cervical spine surgery, and this study suggest that an epidural hematoma occurs in approximately 1 out of 1000 cervical spine surgeries. Prompt diagnosis and treatment may improve the chance of making a complete neurologic recovery, but patients who develop this complication do not show improvements in the health-related quality-of-life measurements

Are We Focused on the Wrong Early Postoperative Quality Metrics? Optimal Realignment Outweighs Perioperative Risk in Adult Spinal Deformity Surgery

BACKGROUND: While reimbursement is centered on 90-day outcomes, many patients may still achieve optimal, long-term outcomes following adult spinal deformity (ASD) surgery despite transient short-term complications. OBJECTIVE: Compare long-term clinical success and cost-utility between patients achieving optimal realignment and suboptimally aligned peers. STUDY DESIGN/SETTING: Retrospective cohort study of a prospectively collected multicenter database. METHODS: ASD patients with two-year (2Y) data included. Groups were propensity score matched (PSM) for age, frailty, body mass index (BMI), Charlson Comorbidity Index (CCI), and baseline deformity. Optimal radiographic criteria are defined as meeting low deformity in all three (Scoliosis Research Society) SRS-Schwab parameters or being proportioned in Global Alignment and Proportionality (GAP). Cost-per-QALY was calculated for each time point. Multivariable logistic regression analysis and ANCOVA (analysis of covariance) adjusting for baseline disability and deformity (pelvic incidence (PI), pelvic incidence minus lumbar lordosis (PI-LL)) were used to determine the significance of surgical details, complications, clinical outcomes, and cost-utility. RESULTS: A total of 930 patients were considered. Following PSM, 253 optimal (O) and 253 not optimal (NO) patients were assessed. The O group underwent more invasive procedures and had more levels fused. Analysis of complications by two years showed that the O group suffered less overall major (38% vs. 52%, CONCLUSIONS: Fewer late complications (mechanical and reoperations) are seen in optimally aligned patients, leading to better long-term cost-utility overall. Therefore, the current focus on avoiding short-term complications may be counterproductive, as achieving optimal surgical correction is critical for long-term success

ACCESS: Design and Sub-System Performance

Establishing improved spectrophotometric standards is important for a broad range of missions and is relevant to many astrophysical problems. ACCESS, "Absolute Color Calibration Experiment for Standard Stars", is a series of rocket-borne sub-orbital missions and ground-based experiments designed to enable improvements in the precision of the astrophysical flux scale through the transfer of absolute laboratory detector standards from the National Institute of Standards and Technology (NIST) to a network of stellar standards with a calibration accuracy of 1% and a spectral resolving power of 500 across the 0.35 -1.7 micrometer bandpass

Correlation between bone density measurements on CT or MRI versus DEXA scan: A systematic review

Background: Novel methods of bone density assessment using computed tomography (CT) and magnetic resonance imaging (MRI) have been increasingly reported in the spine surgery literature. Correlations between these newer measurements and traditional Dual-Energy X-ray Absorptiometry (DEXA) is not well known. The purpose of this study is to perform an updated systematic review of correlations between bone mineral density (BMD) from CT or MRI and DEXA. Methods: Articles published between 2011 and 2021 that reported correlations between the CT-HU or MRI measurements to DEXA t-scores or BMD of lumbar spine or hip were included in this systematic review. Results: A total of 25 studies (15 CT, 10 MRI) met the inclusion criteria with a total number of 2,745 patients. The pooled correlation coefficient of spine CT-HU versus spine DEXA, spine CT-HU versus hip DEXA and spine CT-HU versus lowest t-score were 0.60, 0.50 and 0.60 respectively. Regarding spine DEXA parameters, the pooled r2 for spine CT-HU versus spine t-score was 0.684 and spine CT-HU versus spine BMD was 0.598. Furthermore, in patients undergoing spine surgery in four studies, the pooled correlation between spine CT and spine DEXA was (r2: 0.64). In MRI studies, the pooled r2 of spine MRI versus spine DEXA and spine MRI versus hip DEXA were -0.41 and -0.44 respectively. Conclusions: CT-HU has stronger correlations with DEXA than MRI measurements. Lumbar CT-HU has the highest pooled correlation (r2 = 0.6) with both spine DEXA and lowest skeletal t-score followed by lumbar CT-HU with hip DEXA (r2 = 0.5) and lumbar MRI with hip (r2 = 0.44) and spine (r2 = 0.41) DEXA. Both imaging modalities achieved only a moderate correlation with DEXA. Few studies in both modalities have investigated the correlation in spine surgery populations and the available data shows that the correlations are worse in the degenerative spine population. A careful interruption of CT HU and MRI measurement when evaluation of BMD as they only moderately correlated with DEXA scores. At this time, it is unclear which modality is a better predictor of mechanical complications and clinical outcomes in spine surgery patients

Bone density measured on sagittal reconstructed CT is highly correlated with axial CT but both measurements are only moderately correlated with DEXA T-scores

Background: During the preoperative evaluation of a patient being considered for spinal surgery, Dual-energy x-ray absorptiometry (DEXA) has been traditionally used to diagnose poor bone mineral density (BMD) as a risk factor. As ordering a DEXA can add cost and delay diagnosis, spine surgeons have more recently began to use Hounsfield Units (HU) measured on computed tomography scans (CT) as a measure of BMD. The aim of our study was to evaluate associations between DEXA and HU on lumbar spine CT scans. Methods: Forty-two patients (32 female, 10 male, mean age = 67.7 years) with DEXA and lumbar spine CT scans performed within one year of each other were identified. DEXA T-scores were collected from the hip, forearm and L1-L4. HU was determined using the maximum region of interest within the cancellous area in the mid-vertebral body from L1-L4 in the sagittal and axial planes. Results: Using the lowest T-score, 8 (19 %) cases were osteoporotic and 25 (60 %) were osteopenic. Statistically significant differences in HU were seen in osteoporotic cases (Axial HU = 59.2, Sagittal HU = 61.1, p = 0.006) compared to osteopenic (Axial HU = 119.8, Sagittal HU = 122.9) and normal cases (Axial HU = 141.2, Sagittal HU = 142.3). There were moderate associations between the spine T-scores and CT HUs (Axial HU:r2 = 0.50, Sagittal HU:r2 = 0.49, p < 0.001), weak associations between the Axial HU (r2 = 0.48, p < 0.000) and Sagittal HU (r2 = 0.48, p < 0.000) with hip T-scores, and no correlations with forearm T-scores. There were strong associations between Axial HU and Sagittal HU (r2 = 0.98, p < 0.001). Clinical relevance: The results of the current study show a strong association between the sagittal and axial vertebral HU measurements, which supports the clinical use of either measurement technique. The weak correlation between T-scores and HU is consistent with prior studies and warrants future studies to determine which modality will better predict postoperative mechanical failures in patients undergoing spinal surgery. Level of Evidence: III

Ninety-day complication, revision, and readmission rates for current-generation robot-assisted thoracolumbar spinal fusion surgery: results of a multicenter case series

OBJECTIVE Robotics is a major area for research and development in spine surgery. The high accuracy of robot -assisted placement of thoracolumbar pedicle screws is documented in the literature. The authors present the largest case series to date evaluating 90-day complication, revision, and readmission rates for robot-assisted spine surgery using the current generation of robotic guidance systems. METHODS An analysis of a retrospective, multicenter database of open and minimally invasive thoracolumbar instrumented fusion surgeries using the Mazor X or Mazor X Stealth Edition robotic guidance systems was performed. Patients 18 years of age or older and undergoing primary or revision surgery for degenerative spinal conditions were included. Descriptive statistics were used to calculate rates of malpositioned screws requiring revision, as well as overall complication, revision, and readmission rates within 90 days. RESULTS In total, 799 surgical cases (Mazor X: 48.81%; Mazor X Stealth Edition: 51.19%) were evaluated, involving robot-assisted placement of 4838 pedicle screws. The overall intraoperative complication rate was 3.13%. No intraoperative implant-related complications were encountered. Postoperatively, 129 patients suffered a total of 146 complications by 90 days, representing an incidence of 16.1%. The rate of an unrecognized malpositioned screw resulting in a new postoperative radiculopathy requiring revision surgery was 0.63% (5 cases). Medical and pain-related complications unrelated to hardware placement accounted for the bulk of postoperative complications within 90 days. The overall surgical revision rate at 90 days was 6.63% with 7 implant-related revisions, representing an implant-related revision rate of 0.88%. The 90-day readmission rate was 7.13% with 2 implant-related readmissions, representing an implant-related readmission rate of 0.25% of cases. CONCLUSIONS The results of this multicenter case series and literature review suggest current-generation robotic guidance systems are associated with low rates of intraoperative and postoperative implant-related complications, revisions, and readmissions at 90 days. Future outcomes-based studies are necessary to evaluate complication, revision, and readmission rates compared to conventional surgery

Opioid use prior to surgery is associated with worse preoperative and postoperative patient reported quality of life and decreased surgical cost effectiveness for symptomatic adult spine deformity; A matched cohort analysis.

BackgroundPreoperative opioid is associated with poor postoperative outcomes for several surgical specialties, including neurosurgical, orthopedic, and general surgery. Patients with symptomatic adult spinal deformity (SASD) are among the highest patient populations reporting opioid use prior to surgery. Surgery for SASD has been demonstrated to improve patient reported quality of life, however, little medical economic data exists evaluating impact of preoperative opioid use upon surgical cost-effectiveness for SASD. The purpose of this study was to evaluate the impact that preoperative opioid use has upon SASD surgery including duration of intensive care unit (ICU) and hospital stay, postoperative complications, patient reported outcome measures (PROMs), and surgical cost-effectiveness using a propensity score matched analysis model.MethodsSurgically treated SASD patients enrolled into a prospective multi-center SASD study were assessed for preoperative opioid use, and divided into two cohorts; preoperative opioid users (OPIOID) and preoperative opioid non-users (NON). Propensity score matching (PSM) was used to control for patient age, medical comorbidities, spine deformity type and magnitude, and surgical procedures for OPIOID vs NON. Preoperative and minimum 2-year postoperative PROMs, duration of ICU and hospital stay, postoperative complications, and opioid use at one and two years postoperative were compared for OPIOID vs NON. Preoperative, one year, and minimum two-year postoperative SF6D values were calculated, and one- and two-year postoperative QALYs were calculated using SF6D change from baseline. Hospital costs at the time of index surgery were calculated and cost/QALY compared at one and two years postop for OPIOID vs NON.Results261/357 patients (mean follow-up 3.3 years) eligible for study were evaluated. Following the PSM control, OPIOID (n=97) had similar preoperative demographics, smoking and depression history, spine deformity magnitude, and surgery performed as NON (n=164; p&gt;0.05). Preoperatively, OPIOID reported greater NRS back pain (7.7 vs 6.7) and leg pain (5.2 vs 3.9), worse ODI (50.8 vs 36.9), worse SF-36 PCS (28.8 vs 35.6), and worse SRS-22r self-image (2.3 vs 2.5) than NON, respectively (p&lt;0.05). OPIOID had longer ICU (41.2 vs 21.4 hours) and hospital stay (10.6 vs 8.0 days) than NON, respectively (p&lt;0.05). At last postoperative follow up, OPIOID reported greater NRS back pain (4.1 vs 2.3) and leg pain (2.9 vs 1.7), worse ODI (32.4 vs 19.4), worse SF-36 PCS (37.4 vs 47.0), worse SRS-22r self-image (3.5 vs 4.0), and lower SRS-22r treatment satisfaction score (2.5 vs 4.5) than NON, respectively (p&lt;0.05). At last follow-up postoperative Cost/QALY was higher for OPIOID ($44,558.31) vs NON ($34,304.36; p&lt;0.05). At last follow up OPIOID reported greater postoperative opioid usage than NON [41.2% vs. 12.9%, respectively; odds ratio =4.7 (95% CI=2.6-8.7; p&lt;0.05)].ConclusionsProspective, multi-center, matched analysis demonstrated SASD patients using opioids prior to SASD surgery reported worse preoperative and postoperative quality of life, had longer ICU and hospital stay, had less cost effectiveness of SASD surgery. Preoperative opioid users also reported lower treatment satisfaction, and reported greater postoperative opioid use than non-users. These data should be used to council patients on the negative impact preoperative opioid use can have on SASD surgery