Alba Vila-Casademunt

The Reliability of Sagittal Pelvic Parameters: The Effect of Lumbosacral Instrumentation and Measurement Experience

Study Design. Sagittal pelvic parameters (SPPs) of a representative patient sample drawn from a consecutive adult spinal deformity database were measured using Surgimap Spine. Estimated coefficient of reliability intraclass coefficient (95% confidence interval), standard error of measurement, and mean absolute deviation were used for the analysis. Objective. The primary objective of this study was to assess the reliability of SPP measurements using Surgimap Spine. The secondary objective was to evaluate the impact of pelvic instrumentation as well as the impact of user expertise. Summary of Background Data. The radiographical measurement of SPP is increasingly recognized as playing a critical role in establishing the surgical goals and surgical strategy of many spinal disorders. Although instrumented flatback is a common cause of sagittal malalignment, to our knowledge, SPP measurement reliability has never been assessed in instrumented spines. Methods. Sixty-three adult full-spine standing lateral radiographs (31 with lumbosacral instrumentation) were measured twice by 13 observers using Surgimap Spine. Observers were stratified into 3 levels of experience: high (research coordinators, 4), mid (senior surgeons, 5), and low (junior surgeons, 4). Research coordinators trained all surgeons for less than 30 minutes. Parameters measured were pelvic incidence, pelvic tilt, and sacral slope. Results. Thirteen observers and 63 radiographs generated 817 observations (2 misses). Overall inter- and intraobserver reliability of SPP measurement was excellent (intraclass coefficient > 0.85). Lumbosacral instrumentation did not modify intraobserver reliability but reduced significantly interobserver reliability of pelvic tilt (P = 0.006) and sacral slope (P = 0.007). Experience did not affect intraobserver reliability but interobserver reliability of highly experienced observers was significantly lower (P < 0.05) than among less experienced observers. Conclusion. Measurement of SPP using Surgimap Spine equals or improves previously reported reliability data. Lumbosacral instrumentation reduces interobserver reliability taking it from excellent to moderate in the sacral slope measurement. Inexperienced observers can measure SPP reliably after a short tutorial. Level of Evidence: 4

Posterior thoracic osteotomies

Spinal osteotomies are used to treat partially flexible and fixed deformities. Fixed thoracic spinal deformities have been traditionally treated with anterior release and posterior correction with fusion. In recent decades, it has been shown that posterior-only osteotomies might be sufficient to achieve proper deformity correction with lower complication rates than with combined anterior and posterior procedures. Different types of osteotomies have been described to treat spinal deformities through a single posterior approach. These include posterior column osteotomies such as the Smith-Petersen osteotomy and the Ponte osteotomy, and three-column osteotomies such as the pedicle subtraction osteotomy, the posterior vertebral column resection and the posterior vertebral column decancellation. In general, three-column osteotomies are most commonly performed in the lumbar spine, where the vast majority of reports have focused on. They can also be performed in the thoracic spine in the setting of rigid thoracic deformity. A progressive increase in complications has been reported with more aggressive osteotomies. The aim of this article was to describe the most common posterior spinal osteotomies used to treat adult thoracic spinal deformities, with special emphasis on the technical aspects, complications and outcomes, based on current publications and European Spine Study Group (ESSG) data.

Advantages and Disadvantages of Adult Spinal Deformity Surgery and its Impact on Health-related Quality of Life.

Study Design. Prospective multicenter study of adult spinal deformity (ASD) surgery. Objective. To clarify the effect of ASD surgery on each health-related quality of life (HRQOL) subclass/domain. Summary of Background Data. For patients with ASD, surgery offers superior radiological and HRQOL outcomes compared with nonoperative care. HRQOL may, however, be affected by surgical advantages related to corrective effects, yielding adequate spinopelvic alignment and stability or disadvantages because of long segment fusion. Methods. The study included 170 consecutive patients with ASD from a multicenter database with more than 2-year follow-up period. We analyzed each HRQOL domain/subclass (short form-36 items, Oswestry Disability Index, Scoliosis Research Society-22 [SRS-22] questionnaire), and radiographic parameters preoperatively and at 1 and 2 years postoperatively. We divided the patients into two groups each based on lowest instrumented vertebra (LIV; above L5 or S1 to ilium) or surgeon-determined preoperative pathology (idiopathic or degenerative). Improvement rate (%) was calculated as follows: 100 × |pre.–post.|/preoperative points (%) (+, advantages; –, disadvantages). Results. The scores of all short form-36 items and SRS-22 subclasses improved at 1 and 2 years after surgery, regardless of LIV location and preoperative pathology. Personal care and lifting in Oswestry Disability Index were, however, not improved after 1 year. These disadvantages were correlated to sagittal modifiers of SRS-Schwab classification similar to other HRQOL. The degree of personal care disadvantage mainly depended on LIV location and preoperative pathology. Although personal care improved after 2 years postoperatively, no noticeable improvements in lifting were recorded. Conclusion. HRQOL subclass analysis indicated two disadvantages of ASD surgery, which were correlated to sagittal radiographic measures. Fusion to the sacrum or ilium greatly restricted the ability to stretch or bend, leading to limited daily activities for at least 1 year postoperatively, although this effect may subside after another year. Consequently, spinal surgeons should note the effect of surgical treatment on each HRQOL domain and counsel patients about the implications of surgery. Level of Evidence: 4

Function and Clinical Symptoms are the Main Factors that Motivate Thoracolumbar Adult Scoliosis Patients to Pursue Surgery.

Study Design. A retrospective two-cohort comparative analysis of data collected prospectively in an adult deformity multicenter database. Objective. The aim of this study was to define the radiographic and clinical parameters that motivate adult thoracolumbar (TL) scoliosis patients to undergo surgery. Summary of Background Data. TL curves are a primary concern in adulthood, and it is necessary to establish why patients are motivated to seek surgical intervention. Methods. Patients with only main TL/lumbar (TL/L) idiopathic curves were included, defined as Schwab type L curves and Schwab type D curves in which thoracic curves were <40° and the difference between the TL/L-MT Cobb was ≥15°. Demographic data, health-related quality of life (HRQOL) questionnaires, and 14 different radiological preoperative parameters were assessed. Surgical versus conservative cohorts were compared with the Student t test, Chi-square, and the Mann-Whitney U test. Results. A total of 184 patients met the inclusion criteria. Ninety-four were treated conservatively (C), while 90 underwent surgery (S). No differences were found between groups in terms of demographic or radiographic preoperative data. Age (C: 57.5 ± 18 vs. S: 54.2 ± 18 yr; P = 0.18), coronal TL/L Cobb (C: 52.3° ± 15 vs. S: 50.6° ± 13; P = 0.61), and sagittal alignment (SVA C: 3.1 cm ± 5.7 vs. S: 4.9 cm ± 6.4; P = 0.054) were similar. No differences were found in pelvic parameters (pelvic incidence, pelvic tilt, sacral slope), apical translation, coronal balance, lumbar rotatory subluxation, or lumbar lordosis. However, significant differences were found in HRQOL questionnaires. Surgical patients initially had worse COMI scores (C: 4.6 ± 2.3 vs. S: 6 ± 2.3; P = 0.001), worse ODI scores (C: 27.7 ± 16 vs. S: 38.9 ± 20; P = 0.000), worse SF-36 physical (C: 40.9 ± 8.5 vs. S: 36 ± 9.5; P = 0.001) and mental scores (C: 45.8 ± 12 vs. S: 42.2 ± 11.8; P = 0.032), and worse SRS-22 scores in all domains with mean values under 3.1 points (range = 2.4–3.1). In both SF-36 physical and SRS-22 function, differences between groups were higher than the minimum clinically important difference. Conclusion. After analyzing a large multicenter database, we found that only clinical factors—particularly function impairment—motivated adult TL scoliosis patients to undergo surgery. Demographic and radiographic parameters did not seem to influence decision-making. Level of Evidence: 3

Is Routine Postoperative Radiologic Follow-up Justified in Adolescent Idiopathic Scoliosis?

STUDY DESIGN Retrospective review. OBJECTIVES To determine whether routine periodic radiographic examination is worthwhile in adolescent idiopathic scoliosis (AIS) patients undergoing instrumented fusion with third-generation implants. SUMMARY OF BACKGROUND DATA In common practice, patients who have undergone surgery for idiopathic scoliosis are followed up for a minimum of 2 years by clinical assessment and routine radiographic study at 3, 6, 12, and 24 months. The radiation related to these examinations is not negligible. To our knowledge, the use of routine radiographic follow-up after posterior spinal fusion for adolescent idiopathic scoliosis has not been evaluated. METHODS We retrospectively analyzed full-spine X-rays and clinical records from the first 2 postoperative years of 43 patients. We sought any clinical feature (eg, pain, deformity progression, material protrusion) justifying X-ray, and any relevant radiologic finding (eg, loss of correction, instrumentation loosening, junctional kyphosis). RESULTS Excluding the immediate postoperative films, 14.8% of X-rays were clinically justified, 8.3% were associated with a relevant finding, and 4.3% led to a therapy change. All patients with clinical deformity progression had a relevant X-ray finding. Pain was associated with a relevant finding in 23.5% of cases (positive predictive value, 0.1); 7.4% of films with no clinical justification showed a relevant finding (negative predictive value, 0.86). Lower Risser sign increased the risk of having a relevant radiographic finding (p < .05). CONCLUSIONS With the current use of third-generation implants, routine biplanar postoperative X-rays at 3, 6, 12, and 24 months do not seem to be justified in AIS and should be avoided in mature, asymptomatic patients.

Impact of early unanticipated revision surgery on health-related quality of life after adult spinal deformity surgery

BACKGROUND CONTEXT Revision surgery represents a major event for patients undergoing adult spinal deformity (ASD) surgery. Previous reports suggest that ASD surgery has minimal or no impact on health-related-quality of life (HRQOL) outcomes. PURPOSE The present study aims to investigate the impact of early reoperations within the first year on HRQOL and on the likelihood of reaching the minimally clinically important difference (MCID) after ASD surgery. DESIGN This is a retrospective analysis of prospectively collected data from consecutive surgically treated adult deformity surgery patients included in a multicenter, international database. PATIENT SAMPLE The present study included 280 patients from a multicenter international prospective database. OUTCOME MEASURE Oswestry Disability Index (ODI), Short Form-36 (SF-36), Scoliosis Research Society-22 (SRS-22), MCID were evaluated in this work. METHODS Consecutive surgical patients with ASD recruited prospectively in six different centers from four countries with a minimum 2-year follow-up were stratified into two groups: R (revision surgery within the first year) and NR (no revision). Health-related-quality of life (ODI, SF-36, SRS-22) was assessed and compared at 6-month, 1-year, and 2-year follow-up stages. Statistical analysis included chi-square tests, Student t tests, and linear mixed models. RESULTS Forty-three patients (R Group) received 46 revision surgeries. Nineteen patients (41.3%) had implant-related complications, 9 patients (19.6%) had deep surgical site infections, 9 patients (19.6%) had proximal junctional kyphosis, 3 patients (6.5%) had hematoma, and 6 patients (13%) had other complications. Baseline characteristics differed between groups. At 6 months, all HRQOL scores improved in both groups, except in the SF-36 Mental Component Summary and SRS-22 mental health domain in the R Group. At 1 year, ODI and SRS-22 improvement was significantly greater in the NR Group, exceeding the reported MCID. At the 2-year follow-up, ODI, SRS-22, SF-36 MCS, and SF-36 PCS improvement was similar in both groups. However, postoperative change was only above the MCID for SF-36 PCS, ODI, and SRS-22 in the NR Group. CONCLUSIONS Early unanticipated revision surgery has a negative impact on mental health at 6 months and reduces the chances of reaching an MCID improvement in SRS-22, SF-36 PCS, and ODI at the 2-year follow-up.

Are routine postoperative X-Rays justified in adolescent idiopathic scoliosis?

Results Records from 43 patients (mean age 16.5 years, 93% women) were evaluated. A total of 414 (212 posteroanterior, 202 lateral) full-spine X-rays (9.6/patient) were performed during the first 2 postoperative years: 392 were available for analysis, and 391 had an associated clinical note. Excluding the 89 immediate postoperative films, only 48 of 325 (14.8%) were clinically justified: pain in 17 (34%) patients, clinical progression of deformity in 4 (8%) and previous X-ray finding in 29 (58%). All patients with clinical progression had a relevant X-ray finding. Pain was associated with a relevant finding in 23.5% of cases (positive predictive value 0.1); 7.4% of films with no clinical justification showed a relevant finding (negative predictive value 0.86). Only 4.3% of films led to a therapy change. Lower Risser sign increased the risk of having a relevant radiographic finding (p<0.05). Conclusions Routine 3, 6, 12, and 24-month postoperative X-rays are not justified in AIS and should be avoided in mature, uncomplicated cases.

Minimum clinically important difference of the health-related quality of life scales in adult spinal deformity calculated by latent class analysis: is it appropriate to use the same values for surgical and nonsurgical patients?

BACKGROUND CONTEXT Health-related quality of life (HRQOL) parameters have been shown to be reliable and valid in patients with adult spinal deformity (ASD). Minimum clinically important difference (MCID) has become increasingly important to clinicians in evaluating patients with a threshold of improvement that is clinically relevant. PURPOSE To calculate MCID and minimum detectable change (MDC) values of total scores of the Core Outcome Measures Index (COMI), Oswestry Disability Index (ODI), Physical Component Summary (PCS), Mental Component Summary (MCS) of the Short Form 36 (SF-36), and Scoliosis Research Society 22R (SRS-22R) in surgically and nonsurgically treated ASD patients who have completed an anchor question at pretreatment and 1-year follow-up. STUDY DESIGN/SETTING Prospective cohort. PATIENT SAMPLE Surgical and nonsurgical patients from a multicenter ASD database. OUTCOME MEASURES Self-reported HRQOL measures (COMI, ODI, SF-36, SRS-22R, and anchor question). METHODS A total of 185 surgical and 86 nonsurgical patients from a multicenter ASD database who completed pretreatment and 1-year follow-up HRQOL scales and the anchor question at the first year follow-up were included. The anchor question was used to determine MCID for each HRQOL measure. MCIDs were calculated by an anchor-based method using latent class analysis (LCA) and MDCs by a distribution-based method. RESULTS All differences between means of baseline and first year postoperative total score measures for all scales demonstrated statistically significant improvements in the overall population as well as the surgically treated patients but not in the nonsurgical group. The calculated MDC and MCID values of HRQOL parameters in the entire study population were 1.34 and 2.62 for COMI, 10.65 and 14.31 for ODI, 6.09 and 7.33 for SF-36 PCS, 6.14 and 4.37 for SF-36 MCS, and 0.42 and 0.71 for SRS-22R. The calculated MCID values for surgical and non-surgical treatment groups were 2.76 versus 1.20 for COMI, 14.96 versus 2.45 for ODI, 7.83 versus 2.15 for SF-36 PCS, 5.14 versus 2.03 for SF-36 MCS, and 0.94 versus 0.11 for SRS-22R; the MDC values for surgical and nonsurgical treatment groups were 1.22 versus 1.51 for COMI, 10.27 versus 9.45 for ODI, 5.16 versus 6.77 for SF-36 PCS, 6.05 versus 5.67 for SF-36 MCS, and 0.38 versus 0.43 for SRS-22R. CONCLUSIONS This study has demonstrated that MCID calculations for the HRQOL scales in ASD using LCA yield values comparable to other studies that had used different methodologies. The most important finding was the significantly different MCIDs for COMI, ODI, SF-36 PCS and SRS-22 in the surgically and nonsurgically treated cohorts. This finding suggests that a universal MCID value, inherent to a specific HRQOL for an entire cohort of ASD may not exist. Use of different MCIDs for surgical and nonsurgical patients may be warranted.

Radiographic Axial Malalignment is Associated With Pretreatment Patient-Reported Health-Related Quality of Life Measures in Adult Degenerative Scoliosis: Implementation of a Novel Radiographic Software Tool

STUDY DESIGN Retrospective study of prospectively collected data. OBJECTIVES The purpose of this study was to evaluate the relationship between apical vertebral axial rotation and pretreatment patient-reported health-related quality of life (HRQOL), disability, and pain in patients with adult degenerative scoliosis (ADS) using a novel radiographic software tool. Recent studies have demonstrated that in ADS, sagittal and coronal plane deformity are weakly to moderately associated with HRQOL, disability, and pain. However, as ADS is a three-dimensional spinal deformity, the impact of axial malalignment on HRQOL is yet to be determined. METHODS A total of 74 ADS patients were enrolled. HRQOL measures included the Short Form-36v2 (SF-36v2) and Scoliosis Research Society questionnaire (SRS-22r). Disability and pain measures included the Oswestry Disability Index (ODI) and numeric rating scale back and leg pain. Radiographic measures included Cobb angle (CA), sagittal spinopelvic parameters, lateral and anteroposterior (AP) translation of the apical vertebra. The amount of apical vertebral axial rotation was measured on digital AP radiograph images using a novel software technology. Subjects were stratified into four clinical groups based on the degree of apical vertebral axial rotation. RESULTS Apical vertebral axial rotation showed no association with lateral (r = 0.21; p = .15) and AP (r = 0.08, p = .80) translation of the apical vertebra. A significant moderate association was found between apical vertebral axial rotation and Cobb angle (r = 0.57; p < .05). Patients in the group with the highest degree of apical vertebral axial rotation reported significantly worse ODI and SRS-22r Subtotal and Pain scores (p < .05), irrespective of sagittal spinopelvic parameters. CONCLUSIONS This is the first study that reports on the association between apical vertebral axial rotation and pretreatment HRQOL, disability, and pain in ADS. This study suggests that increased apical vertebral axial rotation is associated with suboptimal pretreatment health status scores. LEVEL OF EVIDENCE Level III.STUDY DESIGN Retrospective study of prospectively collected data. OBJECTIVES The purpose of this study was to evaluate the relationship between apical vertebral axial rotation and pretreatment patient-reported health-related quality of life (HRQOL), disability, and pain in patients with adult degenerative scoliosis (ADS) using a novel radiographic software tool. SUMMARY OF BACKGROUND DATA Recent studies have demonstrated that in ADS, sagittal and coronal plane deformity are weakly to moderately associated with HRQOL, disability, and pain. However, as ADS is a three-dimensional spinal deformity, the impact of axial malalignment on HRQOL is yet to be determined. METHODS A total of 74 ADS patients were enrolled. HRQOL measures included the Short Form-36v2 (SF-36v2) and Scoliosis Research Society questionnaire (SRS-22r). Disability and pain measures included the Oswestry Disability Index (ODI) and numeric rating scale back and leg pain. Radiographic measures included Cobb angle (CA), sagittal spinopelvic parameters, lateral and anteroposterior (AP) translation of the apical vertebra. The amount of apical vertebral axial rotation was measured on digital AP radiograph images using a novel software technology. Subjects were stratified into four clinical groups based on the degree of apical vertebral axial rotation. RESULTS Apical vertebral axial rotation showed no association with lateral (r = 0.21; p = .15) and AP (r = 0.08, p = .80) translation of the apical vertebra. A significant moderate association was found between apical vertebral axial rotation and Cobb angle (r = 0.57; p < .05). Patients in the group with the highest degree of apical vertebral axial rotation reported significantly worse ODI and SRS-22r Subtotal and Pain scores (p < .05), irrespective of sagittal spinopelvic parameters. CONCLUSIONS This is the first study that reports on the association between apical vertebral axial rotation and pretreatment HRQOL, disability, and pain in ADS. This study suggests that increased apical vertebral axial rotation is associated with suboptimal pretreatment health status scores. LEVEL OF EVIDENCE Level III.

Sagittal radiographic parameters demonstrate weak correlations with pretreatment patient-reported health-related quality of life measures in symptomatic de novo degenerative lumbar scoliosis: a European multicenter analysis

OBJECTIVE Previous studies have demonstrated that among patients with adult spinal deformity (ASD), sagittal plane malalignment is poorly tolerated and correlates with suboptimal patient-reported health-related quality of life (HRQOL). These studies included a broad range of radiographic abnormalities and various types of ASD. However, the clinical and radiographic characteristics of de novo degenerative lumbar scoliosis (DNDLS), a subtype of ASD, may influence previously reported correlation strengths. The aim of this study was to correlate sagittal radiographic parameters with pretreatment HRQOL in patients with symptomatic DNDLS. METHODS In this multicenter retrospective study of prospectively collected data, 74 patients with symptomatic DNDLS were enrolled based on anteroposterior and lateral 36-inch standing radiographs. Measurements included Cobb angle, coronal imbalance, pelvic incidence (PI), pelvic tilt (PT), lumbar lordosis (LL), sagittal vertical axis (SVA), thoracic kyphosis, pelvic incidence minus lumbar lordosis (PI-LL), T1-pelvic angle, and global tilt. HRQOL questionnaires included the Oswestry Disability Index (ODI), Scoliosis Research Society (SRS-22r), 36-item Short-Form Health Survey, and numeric rating scale (NRS) for back and leg pain. Correlations between radiographic parameters and HRQOL were assessed. Finally, HRQOL and increasing severity of sagittal modifiers (SVA, PI-LL, and PT) were evaluated. RESULTS Weak correlations were found between SVA and ODI (r = 0.296, p < 0.05) and PT with NRS back pain and the SRS pain domain (r = -0.260, p < 0.05, and r = 0.282, p < 0.05, respectively). Other sagittal radiographic parameters did not show any significant correlation with HRQOL. No significant differences in HRQOL were found concerning the increasing severity of PT, PI-LL, and SVA. CONCLUSIONS While DNDLS is a severe disabling condition, no noteworthy association between clinical and sagittal radiographic parameters was found through this study, demonstrating that sagittal radiographic parameters should not be considered the unique predictor of pretreatment suboptimal health status in this specific group of patients. Future studies addressing classification and treatment algorithms will have to take into account the existing subgroups of ASD.