Francisco Javier Sanchez Perez-Grueso

The Spanish Version of the SRS-22 Patient Questionnaire for Idiopathic Scoliosis : Transcultural Adaptation and Reliability Analysis

Study Design. Validation of the transcultural adaptation of a questionnaire for measuring health-related quality of life. Objectives. To translate and culturally adapt the SRS-22 questionnaire to Spanish. To determine the metric qualities (internal consistency and test–retest reproducibility) of this questionnaire. Summary of Background Data. The SRS-22 Patient Questionnaire has proven to be a valid instrument for clinical assessment of patients with idiopathic scoliosis. The widespread use of the SRS-22 in non–English-speaking countries requires its transcultural adaptation. Methods. Transcultural adaptation of the SRS-22 was carried out according to the International Quality of Life Assessment Project guidelines and included two translations and two back-translations of the material. A committee of experts decided on the final version. The questionnaire was administered to 175 individuals (152 women and 23 men) with idiopathic scoliosis. The mean age of the participants at the time they received the questionnaire was 18.9 years, thoracic curve magnitude was 28.8°, and lumbar curve magnitude was 28.1°. At this time, 85 patients had been treated surgically, 45 had been treated with orthesis, and 45 were under observation. A subgroup of 30 patients completed the questionnaire a second time 1 week later. Internal consistency was determined with Cronbach’s alpha coefficient and test–retest reliability with the intraclass correlation coefficient. Results. The overall alpha coefficient of the questionnaire was 0.89. Coefficients for individual domains were as follows: function/activity, 0.67; pain, 0.81; mental health, 0.83; self-image, 0.73; and satisfaction, 0.78. The questionnaire as a whole had an intraclass correlation coefficient of 0.96. Intraclass correlation coefficients for individual domains were as follows: pain, 0.93; function, 0.82; self-image, 0.94; mental health, 0.94; and satisfaction, 0.98. Conclusions. The Spanish version of the SRS-22 Patient Questionnaire demonstrated adequate internal consistency for the majority of domains and excellent reproducibility. These results suggest that the process of adaptation has produced an instrument that is apparently equivalent to the original and suitable for clinical research.

Validity of the Spanish Version of the Scoliosis Research Society-22 (srs-22) Patient Questionnaire

Study Design. A cross-sectional multicenter study was performed to validate the Spanish version of the Scoliosis Research Society-22 (SRS-22) Patient Questionnaire. Objectives. To determine the construct validity and convergent validity of the instrument. Methods. The Spanish version of the SRS-22 was given to 175 patients with scoliosis (mean age, 19 years old and 86% women). A subgroup of 31 patients also received the Quality of Life for Spine Deformities Profile (QLSDP). Construct validity was studied by factor analysis. Discriminant validity was assessed analyzing the relation between SRS-22 scores and the variables of deformity severity. Convergent validity as related to the QLSDP was studied with a multitrait-multimethod matrix analysis. Results. Factor analysis offered a solution of four factors coherent with the dimensions of the original instrument. SRS-22 scores were worse in older patients (r = −0.34); patients using analgesics demonstrated lower scores (P < 0.001). Patients treated with a brace had a poorer self-image and were less satisfied with their treatment (P < 0.001) than the other treatment groups. Angular improvement of the curves was associated with better self-image scores (r = 0.34). The SRS-22 and QLSDP demonstrated high correlation coefficients in the convergent validity tests (r = 0.84). Conclusion. The Spanish version of the SRS-22 is valid. It has a factorial structure similar to that of the original questionnaire. Moreover, it relates to known severity characteristics of the disease, distinguishes among scoliosis patient groups, and shows concordant values with another valid instrument for measuring self-perceived health.

Early outcomes and complications of posterior vertebral column resection.

BACKGROUND CONTEXT Hyperkyphosis confers a significant risk for neurologic deterioration as well as compromised cardiopulmonary function. Posterior vertebral column resection (PVCR) is a challenging but effective technique for spinal cord decompression and deformity correction that even under the setting of limited resources can be performed to reduce the technical difficulties, the operating time, and possibly the complications of the traditional two-staged vertebral column resection (VCR). PURPOSE To report on the results of VCR performed through a single posterior approach (PVCR) in the treatment of severe rigid kyphosis in a series of patients treated and followed at a Scoliosis Research Society Global Outreach Program site in West Africa. STUDY DESIGN Retrospective case series. PATIENT SAMPLE Forty-five consecutive patients treated with PVCR for correction of severe rigid kyphosis. OUTCOME MEASURES Clinical and radiographic outcomes and complications; Scoliosis Research Society outcome instrument (SRS-22). METHODS From 2002 to 2009, 45 patients (20 male and 25 female) underwent PVCR for kyphosis from congenital deformity (nine) or secondary to tuberculosis of the spine (36). Preoperative demographics, preop and postop neurologic status, SRS-22 scores and complications were recorded; upright full spine X-rays were available in all patients. Mean age was 14 years (6-47 years); mean follow-up 27 months (2-79 months). Mean preoperative kyphosis measured 108°. The deformity apex was resected via a costotransverse (thoracic) or posterolateral (lumbar) approach; neurosurveillance with sensory (somatosensory-evoked potentials) and motor (motor-evoked potentials) potential was used in all cases. Posterior instrumentation was used in all patients, and anterior structural cage was used in 32 patients. RESULTS Intraoperative monitoring changes occurred in 10 patients (22%), and one patient progressed to complete spinal cord injury. Average preoperative local kyphosis was 108° and corrected to 600 postoperatively. Postoperatively, no additional patient showed neurologic deterioration; of the 11 patients with preoperative gait disturbances, 4 improved to normal gait, 5 remained the same, and 2 showed deterioration of their walking ability to nonambulating level. Total SRS-22 scores improved from 3.18 to 3.54 (p=.01), primarily self-image domain. CONCLUSIONS Posterior vertebral column resection was successfully undertaken for the management of thoracic and thoracolumbar hyperkyphosis, demonstrating improvements in overall kyphosis and clinical outcome. Neuromonitoring provided the required safety to perform these challenging complex spine deformity procedures.

Outcome instruments to assess scoliosis surgery

PurposeTo review and summarize the current knowledge regarding the outcome measures used to evaluate scoliosis surgery.MethodsLiterature review.ResultsOutcome instruments should be tested to ensure that they have adequate metric characteristics: content and construct validity, reliability, and responsiveness. In the evaluation of scoliosis, generic instruments to assess health-related quality of life (HRQL) have been used, such as the SF-36 questionnaire and the EuroQol5D instrument. Nonetheless, it is preferable to use disease-specific instruments for this purpose, such as the SRS-22 Patient Questionnaire and the quality of life profile for spinal deformities (QLPSD). More recently, these generic and disease-specific instruments have been complemented with the use of super-specific instruments; i.e., those assessing a single aspect of the condition or specific populations with the condition. The patients’ perception of their trunk deformity and body image has received particular attention, and several instruments are available to evaluate these aspects, such as the Walter-Reed Visual Assessment Scale (WRVAS), the Spinal Appearance Questionnaire (SAQ), and the Trunk Appearance Perception Scale (TAPS). The impacts of brace use can also be measured with specific scales, including the Bad Sobernheim Stress Questionnaire (BSSQ) and the Brace Questionnaire (BrQ). The available instruments to evaluate the treatment for non-idiopathic scoliosis have not been sufficiently validated and analyzed.ConclusionsEvaluation of scoliosis treatment should include the patient’s perspective, which can be obtained with the use of patient-reported outcome measures.

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

Global Alignment and Proportion (GAP) Score: Development and Validation of a New Method of Analyzing Spinopelvic Alignment to Predict Mechanical Complications After Adult Spinal Deformity Surgery.

Background: The restoration of normal sagittal alignment is a critical goal in adult spinal deformity surgery to achieve favorable outcomes and prevent mechanical complications. Schwab sagittal modifiers have been accepted as targets for appropriate alignment, but addressing these targets does not always prevent high mechanical complication or revision rates. This may be because the linear absolute numerical parameters do not cover the whole pelvic incidence spectrum and the distribution of lordosis, pelvic anteversion, and negative malalignment are not considered as potential causes of failure. The aim of the present study was to develop and validate a score based on pelvic-incidence-based proportional parameters to better predict mechanical complications. Methods: Two hundred and twenty-two patients (168 women and 54 men) followed for ≥2 years after posterior fusion at ≥4 levels were included in the study. The mean age (and standard deviation) was 52.2 ± 19.3 years (range, 18 to 84 years), and the mean duration of follow-up was 28.8 ± 8.2 months (range, 24 to 62 months). The global alignment and proportion (GAP) score was developed and validated in groups of patients randomly assigned to derivation (n = 148, 66.7%) and validation (n = 74, 33.3%) cohorts. GAP score parameters were relative pelvic version (the measured minus the ideal sacral slope), relative lumbar lordosis (the measured minus the ideal lumbar lordosis), lordosis distribution index (the L4-S1 lordosis divided by the L1-S1 lordosis multiplied by 100), relative spinopelvic alignment (the measured minus the ideal global tilt), and an age factor. Proximal and distal junctional kyphosis and/or failure, rod breakage, and other implant-related complications were considered mechanical complications. The predictive accuracy of the GAP score was analyzed using receiver operating characteristic (ROC) analyses. Associations between GAP categories and mechanical complications and revisions were analyzed using Cochran-Armitage tests. Results: In the validation cohort, 32 patients (43%) experienced mechanical complications and 17 (23%) underwent mechanical revision. The area under curve for the GAP score predicting mechanical complications was 0.92 (standard error [SE] = 0.034, p < 0.001, 95% [confidence interval [CI] = 0.85 to 0.98). Postoperatively, patients with a proportioned spinopelvic state according to the GAP score had a mechanical complication rate of 6% while those with a moderately or severely disproportioned spinopelvic state had rates of 47% and 95%, respectively. Conclusions: The GAP score is a new pelvic-incidence-based proportional method of analyzing the sagittal plane that predicts mechanical complications in patients undergoing surgery for adult spinal deformity. Setting surgical goals according to the GAP score may decrease the prevalence of mechanical complications.

How do idiopathic scoliosis patients who improve after surgery differ from those who do not exceed a minimum detectable change

IntroductionThe minimum detectable change (MDC) of the SRS-22 subtotal score is 6.8 points. With the use of this value, patients who have undergone surgery for idiopathic scoliosis can be dichotomized into two groups: the successful (S) group (those who have reached or exceeded this limit) and the unsuccessful (Un-S) group (those in whom the change was smaller). The aim of this study was to analyze the clinical and radiological differences between these patient groups, as well as those related to the surgical technique.Material and MethodsThe study included 91 patients (77 women and 14 men, mean age 18.1 years). All patients completed the SRS-22 questionnaire preoperatively and at follow-up (mean 45.6 months). In addition, radiological and surgical data were collected: levels instrumented, number of fused vertebrae, and use of thoracoplasty.ResultsBased on the MDC of the SRS-22 subtotal score, patients were assigned to the Un-S group (44 cases, 48.4%) or S group (47 cases). Groups were similar in age, sex, number of fused vertebrae, percentage of patients who underwent thoracoplasty, and the upper and lower instrumented levels. The magnitude of the major curve and percentage of correction after surgery were also similar (Un-S group 62.3º, 53.2%; S group 64.3º, 49.9%). As compared to Un-S group, S patients had a poorer preop score in all the SRS-22 domains, and a clinically significant postop improvement in pain, perceived body image, mental health, and subtotal score. In contrast, the Un-S group showed a worsening of pain, function, mental health, and subtotal score, and a clinically nonsignificant improvement in perceived body image on the follow-up questionnaire. There were no significant differences in the satisfaction domain score between groups (4.36 vs. 4.62). On ROC curve analysis, a preop subtotal score of 74 points predicted allocation to the S or Un-S group at follow-up with 79% sensitivity and 76% specificity.ConclusionThe preop subtotal score of the SRS-22 is a good predictor of the clinical response to surgery.

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

Gradual scoliosis correction over time with shape-memory metal: a preliminary report of an experimental study.

Background Severe and progressive scoliosis is a complex threedimensional spinal deformity that commonly requires treatment to address curve progression during growth. Standard treatment options for progressive scoliosis are essentially limited to bracing or surgery. Brace treatment is noninvasive and preserves growth; however it is only modestly successful in preventing curve progression and has a negative psychological impact [1-3] that may decrease patient compliance. Instead, surgical treatment with an instrumented spinal arthrodesis usually results in good deformity correction but has several risks. Those risks are associated to the invasiveness of spinal arthrodesis, the instantaneous correction of spinal deformity, and the altered biomechanics of the fused spine. Spinal fusion can have deleterious effects on subsequent development. Besides the known loss of motion and risk of adjacent segment disease with long-segment fusion, the loss of growth potential can lead to a significant decrease in trunk height and may negatively impact pulmonary development. Therefore, recent interest has been focused on new strategies for the effective surgical management of severe scoliosis in young children without the use of multisegmental spinal fusion. Fusionless scoliosis surgery provides theoretical advantages over traditional surgical arthrodesis, including the potential preservation of growth, motion and function of the spine [4]. In this way, several methods have been developed to treat scoliosis in young patients that allow the natural growth and elongation of the developing spine.

Global tilt and lumbar lordosis index: two parameters correlating with health-related quality of life scores—but how do they truly impact disability?

BACKGROUND CONTEXT Many radiological parameters have been reported to correlate with patients disability including sagittal vertical axis (SVA), pelvic tilt (PT), and pelvic incidence minus lumbar lordosis (PI-LL). European literature reports other parameters such as lumbar lordosis index (LLI) and the global tilt (GT). If most parameters correlate with health-related quality of life scores (HRQLs), their impact on disability remains unclear. PURPOSE This study aimed to validate these parameters by investigating their correlation with HRQLs. It also aimed to evaluate the relationship between each of these sagittal parameters and HRQLs to fully understand the impact in adult spinal deformity management. STUDY DESIGN A retrospective review of a multicenter, prospective database was carried out. PATIENT SAMPLE The database inclusion criteria were adults (>18 years old) presenting any of the following radiographic parameters: scoliosis (Cobb ≥20°), SVA ≥5 cm, thoracic kyphosis ≥60° or PT ≥25°. All patients with complete data at baseline were included. OUTCOME MEASURES Health-related quality of life scores, demographic variables (DVs), and radiographic parameters were collected at baseline. METHODS Differences in HRQLs among groups of each DV were assessed with analyses of variance. Correlations between radiographic variables and HRQLs were assessed using the Spearman rank correlation. Multivariate linear regression models were fitted for each of the HRQLs (Oswestry Disability Index [ODI], Scoliosis Research Society-22 subtotal score, or physical component summaries) with sagittal parameters and covariants as independent variables. A p<.05 value was considered statistically significant. RESULTS Among a total of 755 included patients (mean age, 52.1 years), 431 were non-surgical candidates and 324 were surgical candidates. Global tilt and LLI significantly correlated with HRQLs (r=0.4 and -0.3, respectively) for univariate analysis. Demographic variables such as age, gender, body mass index, past surgery, and surgical or non-surgical candidate were significant predictors of ODI score. The likelihood ratio tests for the addition of the sagittal parameters showed that SVA, GT, T1 sagittal tilt, PI-LL, and LLI were statistically significant predictors for ODI score even adjusted for covariates. The differences of R2 values from Model 1 were 1.5% at maximum, indicating that the addition of sagittal parameters to the reference model increased only 1.5% of the variance of ODI explained by the models. CONCLUSION GT and LLI appear to be independent radiographic parameters impacting ODI variance. If most of the parameters described in the literature are correlated with ODI, the impact of these radiographic parameters is less than 2% of ODI variance, whereas 40% are explained by DVs. The importance of radiographic parameters lies more on their purpose to describe and understand the malalignment mechanisms than their univariate correlation with HRQLs.