Purpose
Information about the cost-effectiveness of surgical procedures for adult spinal deformity (ASD) is critical for providing appropriate treatments for these patients. The purposes of this ...study were to compare the direct cost and cost-effectiveness of surgery for ASD in the United States (US) and Japan (JP).
Methods
Retrospective analysis of 76 US and 76 JP patients receiving surgery for ASD with ≥2-year follow-up was identified. Data analysis included preoperative and postoperative demographic, radiographic, health-related quality of life (HRQOL), and direct cost for surgery. An incremental cost-effectiveness ratio (ICER) was determined using cost/quality-adjusted life years (QALY). The cost/QALY was calculated from the 2-year cost and HRQOL data.
Results
JP exhibited worse baseline spinopelvic alignment than the US (pelvic incidence and lumbar lordosis: 35.4° vs 22.7°,
p
< 0.01). The US had more three-column osteotomies (50 vs 16%), and shorter hospital stay (7.9 vs 22.7 days) (
p
< 0.05). The US demonstrated worse postoperative ODI (41.3 vs. 33.9%) and greater revision surgery rate (40 vs 10%) (
p
< 0.05). Due to the high initial cost and revision frequency, the US had greater total cost ($92,133 vs. $49,647) and cost/QALY ($511,840 vs. $225,668) at 2-year follow-up (
p
< 0.05).
Conclusion
Retrospective analysis comparing the direct costs and cost-effectiveness of ASD surgery in the US vs JP demonstrated that the total direct costs and cost/QALY were substantially higher in the US than JP. Variations in patient cohort, healthcare costs, revision frequencies, and HRQOL improvement influenced the cost/QALY differential between these countries.
BACKGROUND:The SRS-Schwab classification of adult spinal deformity (ASD) is a validated system that provides a common language for the complex pathology of ASD. Classification reliability has been ...reported; however, correlation with treatment has not been assessed.
OBJECTIVE:To assess the clinical relevance of the SRS-Schwab classification based on correlations with health-related quality of life (HRQOL) measures and the decision to pursue operative vs nonoperative treatment.
METHODS:Prospective analysis of consecutive ASD patients (18 years of age and older) collected through a multicenter group. The SRS-Schwab classification includes a curve type descriptor and 3 sagittal spinopelvic modifiers (sagittal vertical axis, pelvic tilt, pelvic incidence/lumbar lordosis mismatch). Differences in demographics, HRQOL (Oswestry Disability Index, SRS-22, Short Form-36), and classification between operative and nonoperative patients were evaluated.
RESULTS:A total of 527 patients (mean age, 52.9 years; range, 18.4-85.1 years) met inclusion criteria. Significant differences in HRQOL were identified based on SRS-Schwab curve type, with thoracolumbar and primary sagittal deformities associated with greater disability and poorer health status than thoracic or double curve deformities. Operative patients had significantly poorer grades for each of the sagittal spinopelvic modifiers, and progressively higher grades were associated with significantly poorer HRQOL (P < .05). Patients with worse sagittal spinopelvic modifier grades were significantly more likely to require major osteotomies, iliac fixation, and decompression (P ≤ .009).
CONCLUSION:The SRS-Schwab classification provides a validated language to describe and categorize ASD. This study demonstrates that the SRS-Schwab classification reflects severity of disease state based on multiple measures of HRQOL and significantly correlates with the important decision of whether to pursue operative or nonoperative treatment.
ABBREVIATIONS:ASD, adult spinal deformityCCI, Charlson Comorbidity IndexHRQOL, health-related quality of lifeODI, Oswestry Disability IndexPI-LL, pelvic incidence minus lumbar lordosisPT, pelvic tilt; SVA, sagittal vertical axis
Abstract
BACKGROUND:
Positive spinal regional and global sagittal malalignment has been repeatedly shown to correlate with pain and disability in thoracolumbar fusion.
OBJECTIVE:
To evaluate the ...relationship between regional cervical sagittal alignment and postoperative outcomes for patients receiving multilevel cervical posterior fusion.
METHODS:
From 2006 to 2010, 113 patients received multilevel posterior cervical fusion for cervical stenosis, myelopathy, and kyphosis. Radiographic measurements made at intermediate follow-up included the following: (1) C1-C2 lordosis, (2) C2-C7 lordosis, (3) C2-C7 sagittal vertical axis (C2-C7 SVA; distance between C2 plumb line and C7), (4) center of gravity of head SVA (CGH-C7 SVA), and (5) C1-C7 SVA. Health-related quality-of-life measures included neck disability index (NDI), visual analog pain scale, and SF-36 physical component scores. Pearson product-moment correlation coefficients were calculated between pairs of radiographic measures and health-related quality-of-life scores.
RESULTS:
Both C2-C7 SVA and CGH-C7 SVA negatively correlated with SF-36 physical component scores (r = −0.43, P < .001 and r = −0.36, P = .005, respectively). C2-C7 SVA positively correlated with NDI scores (r = 0.20, P = .036). C2-C7 SVA positively correlated with C1-C2 lordosis (r = 0.33, P = .001). For significant correlations between C2-C7 SVA and NDI scores, regression models predicted a threshold C2-C7 SVA value of approximately 40 mm, beyond which correlations were most significant.
CONCLUSION:
Our findings demonstrate that, similar to the thoracolumbar spine, the severity of disability increases with positive sagittal malalignment following surgical reconstruction.
Multicenter, retrospective series.
To analyze the incidence, mode, and location of acute proximal junctional failures (APJFs) after surgical treatment of adult spinal deformity.
Early proximal ...junctional failures above adult deformity constructs are a serious clinical problem; however, the incidence and nature of early APJFs remain unclear.
A total of 1218 consecutive adult spinal deformity surgeries across 10 deformity centers were retrospectively reviewed to evaluate the incidence and nature of APJF, defined as any of the following within 28 weeks of index procedure: minimum 15° post-operative increase in proximal junctional kyphosis, vertebral fracture of upper instrumented vertebrae (UIV) or UIV + 1, failure of UIV fixation, or need for proximal extension of fusion within 6 months of surgery.
Sixty-eight APJF cases were identified out of 1218 consecutive surgeries (5.6%). Patients had a mean age of 63 years (range, 26-82 yr), mean fusion levels of 9.8 (range, 4-18), and mean time to APJF of 11.4 weeks (range, 1.5-28 wk). Fracture was the most common failure mode (47%), followed by soft-tissue failure (44%). Failures most often occurred in the thoracolumbar region (TL-APJF) compared with the upper thoracic region (UT-APJF), with 66% of patients experiencing TL-APJF compared with 34% experiencing UT-APJF. Fracture was significantly more common for TL-APJF relative to UT-APJF (P = 0.00), whereas soft-tissue failure was more common for UT-APJF (P < 0.02). Patients experiencing TL-APJF were also older (P = 0.00), had fewer fusion levels (P = 0.00), and had worse postoperative sagittal vertical axis (P < 0.01).
APJFs were identified in 5.6% of patients undergoing surgical treatment of adult spinal deformity, with failures occurring primarily in the TL region of the spine. There is evidence that the mode of failure differs depending on the location of UIV, with TL failures more likely due to fracture and UT failures more likely due to soft-tissue failures.
BACKGROUND:High-quality studies that compare operative and nonoperative treatment for adult spinal deformity (ASD) are needed.
OBJECTIVE:To compare outcomes of operative and nonoperative treatment ...for ASD.
METHODS:This is a multicenter, prospective analysis of consecutive ASD patients opting for operative or nonoperative care. Inclusion criteria were age >18 years and ASD. Operative and nonoperative patients were propensity matched with the baseline Oswestry Disability Index, Scoliosis Research Society-22r, thoracolumbar/lumbar Cobb angle, pelvic incidence–to–lumbar lordosis mismatch (PI-LL), and leg pain score. Analyses were confined to patients with a minimum of 2 years of follow-up.
RESULTS:Two hundred eighty-six operative and 403 nonoperative patients met the criteria, with mean ages of 53 and 55 years, 2-year follow-up rates of 86% and 55%, and mean follow-up of 24.7 and 24.8 months, respectively. At baseline, operative patients had significantly worse health-related quality of life (HRQOL) based on all measures assessed (P < .001) and had worse deformity based on pelvic tilt, pelvic incidence–to–lumbar lordosis mismatch, and sagittal vertical axis (P ≤ .002). At the minimum 2-year follow-up, all HRQOL measures assessed significantly improved for operative patients (P < .001), but none improved significantly for nonoperative patients except for modest improvements in the Scoliosis Research Society-22r pain (P = .04) and satisfaction (P < .001) domains. On the basis of matched operative-nonoperative cohorts (97 in each group), operative patients had significantly better HRQOL at follow-up for all measures assessed (P < .001), except Short Form-36 mental component score (P = .06). At the minimum 2-year follow-up, 71.5% of operative patients had ≥1 complications.
CONCLUSION:Operative treatment for ASD can provide significant improvement of HRQOL at a minimum 2-year follow-up. In contrast, nonoperative treatment on average maintains presenting levels of pain and disability.
ABBREVIATIONS:ASD, adult spinal deformityHRQOL, health-related quality of lifeLL, lumbar lordosisMCID, minimal clinically important differenceNRS, numeric rating scaleODI, Oswestry Disability IndexPI, pelvic incidenceSF-36, Short Form-36SRS-22r, Scoliosis Research Society-22rSVA, sagittal vertical axis
Abstract
BACKGROUND:
Positive spinal regional and global sagittal malalignment has been repeatedly shown to correlate with pain and disability in thoracolumbar fusion.
OBJECTIVE:
To evaluate the ...relationship between regional cervical sagittal alignment and postoperative outcomes for patients receiving multilevel cervical posterior fusion.
METHODS:
From 2006 to 2010, 113 patients received multilevel posterior cervical fusion for cervical stenosis, myelopathy, and kyphosis. Radiographic measurements made at intermediate follow-up included the following: (1) C1-C2 lordosis, (2) C2-C7 lordosis, (3) C2-C7 sagittal vertical axis (C2-C7 SVA; distance between C2 plumb line and C7), (4) center of gravity of head SVA (CGH-C7 SVA), and (5) C1-C7 SVA. Health-related quality-of-life measures included neck disability index (NDI), visual analog pain scale, and SF-36 physical component scores. Pearson product-moment correlation coefficients were calculated between pairs of radiographic measures and health-related quality-of-life scores.
RESULTS:
Both C2-C7 SVA and CGH-C7 SVA negatively correlated with SF-36 physical component scores (r =−0.43, P< .001 and r =−0.36, P = .005, respectively). C2-C7 SVA positively correlated with NDI scores (r = 0.20, P = .036). C2-C7 SVA positively correlated with C1-C2 lordosis (r = 0.33, P = .001). For significant correlations between C2-C7 SVA and NDI scores, regression models predicted a threshold C2-C7 SVA value of approximately 40 mm, beyond which correlations were most significant.
CONCLUSION:
Our findings demonstrate that, similar to the thoracolumbar spine, the severity of disability increases with positive sagittal malalignment following surgical reconstruction.
Propensity score matched analysis of a multi-center prospective adult spinal deformity (ASD) database.
Evaluate if surgical implant prophylaxis combined with avoidance of sagittal overcorrection more ...effectively prevents proximal junctional failure (PJF) than use of surgical implants alone.
PJF is a severe form of proximal junctional kyphosis (PJK). Efforts to prevent PJF have focused on use of surgical implants. Less information exists on avoidance of overcorrection of age-adjusted sagittal alignment to prevent PJF.
Surgically treated ASD patients (age ≥18 yrs; ≥5 levels fused, ≥1 year follow-up) enrolled into a prospective multi-center ASD database were propensity score matched (PSM) to control for risk factors for PJF. Patients evaluated for use of surgical implants to prevent PJF (IMPLANT) versus no implant prophylaxis (NONE), and categorized by the type of implant used (CEMENT, HOOK, TETHER). Postoperative sagittal alignment was evaluated for overcorrection of age-adjusted sagittal alignment (OVER) versus within sagittal parameters (ALIGN). Incidence of PJF was evaluated at minimum 1 year postop.
Six hundred twenty five of 834 eligible for study inclusion were evaluated. Following PSM to control for confounding variables, analysis demonstrated the incidence of PJF was lower for IMPLANT (n = 235; 10.6%) versus NONE (n = 390: 20.3%; P < 0.05). Use of transverse process hooks at the upper instrumented vertebra (HOOK; n = 115) had the lowest rate of PJF (7.0%) versus NONE (20.3%; P < 0.05). ALIGN (n = 246) had lower incidence of PJF than OVER (n = 379; 12.0% vs. 19.2%, respectively; P < 0.05). The combination of ALIGN-IMPLANT further reduced PJF rates (n = 81; 9.9%), while OVER-NONE had the highest rate of PJF (n = 225; 24.2%; P < 0.05).
Propensity score matched analysis of 625 ASD patients demonstrated use of surgical implants alone to prevent PJF was less effective than combining implants with avoidance of sagittal overcorrection. Patients that received no PJF implant prophylaxis and had sagittal overcorrection had the highest incidence of PJF.
3.
Hip osteoarthritis often coexists with adult spinal deformity, an abnormality in which sagittal spinopelvic malalignment is present. Debate exists whether to perform spinal realignment correction or ...total hip arthroplasty first. Hip extension and pelvic tilt are important compensatory mechanisms in the setting of sagittal spinopelvic malalignment and change after spinal realignment. We performed this study to evaluate the effect that the spinal realignment surgical procedure has on acetabular anteversion.
This study is a retrospective review of a multicenter, prospective, consecutive database of patients with adult spinal deformity who underwent surgical spinal realignment. Only patients who already had undergone a total hip arthroplasty prior to the spinal realignment procedure were retained for analysis. Patients were excluded if they had insufficient imaging or large-head, metal-on-metal bearings or they had undergone revision total hip arthroplasty in the study period. Acetabular anteversion was calculated via the ellipse method on a standing, posterior-anterior, 90-cm radiograph with a well-centered pelvis. Anteversion was measured preoperatively and at six weeks or three months after the spinal realignment procedure. Spinopelvic parameters measured included pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, T1 pelvic angle, sagittal vertical axis, T1-spinopelvic inclination, and thoracic kyphosis.
Forty-one hips (thirty-three patients) were identified. Acetabular anteversion significantly reduced (p < 0.001) after spinal correction by mean change of -4.96° (range, -22.32° to +2.36°). The change in anteversion correlated with the changes in sagittal pelvic orientation (0.828 for the pelvic tilt, -0.757 for the sacral slope, and -0.691 for the lumbar lordosis) and global spinopelvic alignment (0.579 for the sagittal vertical axis and 0.585 for the T1 pelvic angle). Regression analysis revealed that anteversion decreased by 1° for each of the following spinopelvic parameter changes (p < 0.001): 1.105° for spinopelvic tilt, 1.032° for sacral slope, and 3.163° for lumbar lordosis.
Patients with spinopelvic malalignment had a high prevalence of excessively anteverted acetabular components. Sagittal spinal correction following total hip arthroplasty resulted in reduced acetabular anteversion, which may have implications for stability. Changes in anteversion are most closely related to changes in pelvic tilt in an almost one-to-one ratio.
Abstract
BACKGROUND: Over the last several decades, significant advances have occurred in the assessment and management of spinal deformity.
OBJECTIVE: The primary focus of this narrative review is ...on recent advances in adult thoracic, thoracolumbar, and lumbar deformities, with additional discussions of advances in cervical deformity and pediatric deformity.
METHODS: A review of recent literature was conducted.
RESULTS: Advances in adult thoracic, thoracolumbar, and lumbar deformities reviewed include the growing applications of stereoradiography, development of new radiographic measures and improved understanding of radiographic alignment objectives, increasingly sophisticated tools for radiographic analysis, strategies to reduce the occurrence of common complications, and advances in minimally invasive techniques. In addition, discussion is provided on the rapidly advancing applications of predictive analytics and outcomes assessments that are intended to improve the ability to predict risk and outcomes. Advances in the rapidly evolving field of cervical deformity focus on better understanding of how cervical alignment is impacted by thoracolumbar regional alignment and global alignment and how this can affect surgical planning. Discussion is also provided on initial progress toward development of a comprehensive cervical deformity classification system. Pediatric deformity assessment has been substantially improved with low radiation-based 3-D imaging, and promising clinical outcomes data are beginning to emerge on the use of growth-friendly implants.
CONCLUSION: It is ultimately through the reviewed and other recent and ongoing advances that care for patients with spinal deformity will continue to evolve, enabling better informed treatment decisions, more meaningful patient counseling, reduced complications, and achievement of desired clinical outcomes.