Study Design.This study is a retrospective review of 752 patients with adult spinal deformity enrolled in a multicenter prospective database in 2002 and 2003. Patients with positive sagittal balance (N = 352) were further evaluated regarding radiographic parameters and health status measures, includ

The Impact of Positive Sagittal Balance in Adult Spinal Deformity

Study design This study is a retrospective review of the initial enrollment data from a prospective multicentered study of adult spinal deformity. Objectives The purpose of this study is to correlate radiographic measures of deformity with patient-based outcome measures in adult scoliosis. Summary of background data Prior studies of adult scoliosis have attempted to correlate radiographic appearance and clinical symptoms, but it has proven difficult to predict health status based on radiographic measures of deformity alone. The ability to correlate radiographic measures of deformity with symptoms would be useful for decision-making and surgical planning. Methods The study correlates radiographic measures of deformity with scores on the Short Form-12, Scoliosis Research Society-29, and Oswestry profiles. Radiographic evaluation was performed according to an established positioning protocol for anteroposterior and lateral 36-inch standing radiographs. Radiographic parameters studied were curve type, curve location, curve magnitude, coronal balance, sagittal balance, apical rotation, and rotatory subluxation. Results The 298 patients studied include 172 with no prior surgery and 126 who had undergone prior spine fusion. Positive sagittal balance was the most reliable predictor of clinical symptoms in both patient groups. Thoracolumbar and lumbar curves generated less favorable scores than thoracic curves in both patient groups. Significant coronal imbalance of greater than 4 cm was associated with deterioration in pain and function scores for unoperated patients but not in patients with previous surgery. Conclusions This study suggests that restoration of a more normal sagittal balance is the critical goal for any reconstructive spine surgery. The study suggests that magnitude of coronal deformity and extent of coronal correction are less critical parameters.

Correlation of radiographic parameters and clinical symptoms in adult scoliosis

STUDY DESIGN Prospective radiographic and clinical analysis. OBJECTIVE Investigate the relationship between spino-pelvic parameters and patient self reported outcomes on adult subjects with spinal deformities. SUMMARY OF BACKGROUND DATA It is becoming increasingly recognized that the study of spinal alignment should include pelvic position. While pelvic incidence determines lumbar lordosis, pelvic tilt (PT) is a positional parameter reflecting compensation to spinal deformity. Correlation between plumbline offset (sagittal vertical axis [SVA]) and Health Related Quality of Life (HRQOL) measures has been demonstrated, but such a study is lacking for PT. METHODS This prospective study was carried out on 125 adult patients suffering from spinal deformity (mean age: 57 years). Full-length free-standing radiographs including the spine and pelvis were available for all patients. HRQOL instruments included: Oswestry Disability Index, Short Form-12, Scoliosis Research Society. Correlation analysis between radiographic spinopelvic parameters and HRQOL measures was pursued. RESULTS Correlation analysis revealed no significance pertaining to coronal plane parameters. Significant sagittal plane correlations were identified. SVA and truncal inclination measured by T1 spinopelvic inclination (T1-SPI) (angle between T1-hip axis and vertical) correlated with: Scoliosis Research Society (appearance, activity, total score), Oswestry Disability Index, and Short Form-12 (physical component score). Correlation coefficients ranged from 0.42 < r < 0.55 (P < 0.0001). T1-SPI revealed greater correlation with HRQOL compared to SVA. PT showed correlation with HRQOL (0.28 < r < 0.42) and with SVA (r = 0.64, P < 0.0001). CONCLUSION This study confirms that pelvic position measured via PT correlates with HRQOL in the setting of adult deformity. High values of PT express compensatory pelvic retroversion for sagittal spinal malalignment. This study also demonstrates significant T1-SPI correlation with HRQOL measures and outperforms SVA. This parameter carries the advantage of being an angular measurement which avoids the error inherent in measuring offsets in noncalibrated radiographs.

Pelvic tilt and truncal inclination: two key radiographic parameters in the setting of adults with spinal deformity.

Study design Inter- and intra-rater variability study. Objective On the basis of a Scoliosis Research Society effort, this study seeks to determine whether the new adult spinal deformity (ASD) classification system is clear and reliable. Summary of background data A classification of adult ASD can serve several purposes, including consistent characterization of a clinical entity, a basis for comparing different treatments, and recommended treatments. Although pediatric scoliosis classifications are well established, an ASD classification is still being developed. A previous classification developed by Schwab et al has met with clinical relevance but did not include pelvic parameters, which have shown substantial correlation with health-related quality of life measures in recent studies. Methods Initiated by the Scoliosis Research Society Adult Deformity Committee, this study revised a previously published classification to include pelvic parameters. Modifier cutoffs were determined using health-related quality of life analysis from a multicenter database of adult deformity patients. Nine readers graded 21 premarked cases twice each, approximately 1 week apart. Inter- and intra-rater variability and agreement were determined for curve type and each modifier separately. Fleiss' kappa was used for reliability measures, with values of 0.00 to 0.20 considered slight, 0.21 to 0.40 fair, 0.41 to 0.60 moderate, 0.61 to 0.80 substantial, and 0.81 to 1.00 almost perfect agreement. Results Inter-rater kappa for curve type was 0.80 and 0.87 for the 2 readings, respectively, with modifier kappas of 0.75 and 0.86, 0.97 and 0.98, and 0.96 and 0.96 for pelvic incidence minus lumbar lordosis (PI-LL), pelvic tilt (PT), and sagittal vertical axis (SVA), respectively. By the second reading, curve type was identified by all readers consistently in 66.7%, PI-LL in 71.4%, PT in 95.2%, and SVA in 90.5% of cases. Intra-rater kappa averaged 0.94 for curve type, 0.88 for PI-LL, 0.97 for PT, and 0.97 for SVA across all readers. Conclusion Data from this study show that there is excellent inter- and intra-rater reliability and inter-rater agreement for curve type and each modifier. The high degree of reliability demonstrates that applying the classification system is easy and consistent.

Scoliosis Research Society-Schwab adult spinal deformity classification: a validation study.

Study design Current concepts review. Objective Outline the basic principles in the evaluation and treatment of adult spinal deformity patients with a focus on goals to achieve during surgical realignment surgery. Summary of background data Proper global alignment of the spine is critical in maintaining standing posture and balance in an efficient and pain-free manner. Outcomes data demonstrate the clinical effect of spinopelvic malalignment and form a basis for realignment strategies. Methods Correlation between certain radiographic parameters and patient self-reported pain and disability has been established. Using normative values for several important spinopelvic parameters (including sagittal vertical axis, pelvic tilt, and lumbar lordosis), spinopelvic radiographic realignment objectives were identified as a tool for clinical application. Because of the complex relationship between the spine and the pelvis in maintaining posture and the wide range of "normal" values for the associated parameters, a focus on global alignment, with proportionality of individual parameters to each other, was pursued to provide clinical relevance to planning realignment for deformity across a range of clinical cases. Conclusion Good clinical outcome requires achieving proper spinopelvic alignment in the treatment of adult spinal deformity. Although variations in pelvic morphology exist, a framework has been established to determine ideal values for regional and global parameter in an individualized patient approach. When planning realignment surgery for adult spinal deformity, restoring low sagittal vertical axis and pelvic tilt values are critical goals, and should be combined with proportional lumbar lordosis to pelvic incidence.

Adult spinal deformity-postoperative standing imbalance: how much can you tolerate? An overview of key parameters in assessing alignment and planning corrective surgery.

Study design A prospective self-assessment analysis and evaluation of nutritional and radiographic parameters in a consecutive series of healthy adult volunteers older than 60 years. Objectives To ascertain the prevalence of adult scoliosis, assess radiographic parameters, and determine if there is a correlation with functional self-assessment in an aged volunteer population. Summary of background data There exists little data studying the prevalence of scoliosis in a volunteer aged population, and correlation between deformity and self-assessment parameters. Methods There were 75 subjects in the study. Inclusion criteria were: age > or =60 years, no known history of scoliosis, and no prior spine surgery. Each subject answered a RAND 36-Item Health Survey questionnaire, a full-length anteroposterior standing radiographic assessment of the spine was obtained, and nutritional parameters were analyzed from blood samples. For each subject, radiographic, laboratory, and clinical data were evaluated. The study population was divided into 3 groups based on frontal plane Cobb angulation of the spine. Comparison of the RAND 36-Item Health Surveys data among groups of the volunteer population and with United States population benchmark data (age 65-74 years) was undertaken using an unpaired t test. Any correlation between radiographic, laboratory, and self-assessment data were also investigated. Results The mean age of the patients in this study was 70.5 years (range 60-90). Mean Cobb angle was 17 degrees in the frontal plane. In the study group, 68% of subjects met the definition of scoliosis (Cobb angle >10 degrees). No significant correlation was noted among radiographic parameters and visual analog scale scores, albumin, lymphocytes, or transferrin levels in the study group as a whole. Prevalence of scoliosis was not significantly different between males and females (P > 0.03). The scoliosis prevalence rate of 68% found in this study reveals a rate significantly higher than reported in other studies. These findings most likely reflect the targeted selection of an elderly group. Although many patients with adult scoliosis have pain and dysfunction, there appears to be a large group (such as the volunteers in this study) that has no marked physical or social impairment. Conclusions Previous reports note a prevalence of adult scoliosis up to 32%. In this study, results indicate a scoliosis rate of 68% in a healthy adult population, with an average age of 70.5 years. This study found no significant correlations between adult scoliosis and visual analog scale scores or nutritional status in healthy, elderly volunteers.

Adult scoliosis: prevalence, SF-36, and nutritional parameters in an elderly volunteer population

STUDY DESIGN Prospective analysis of a consecutive series of adult patients with adolescent idiopathic scoliosis of the adult and de novo degenerative scoliosis. OBJECTIVES To clinically and radiographically study two populations of adult patients with either adolescent idiopathic scoliosis of the adult or de novo degenerative scoliosis in a quantitative manner to identify reliable radiographic parameters that correlate with clinical symptoms. SUMMARY AND BACKGROUND Although there are many causes of spinal deformity in the adult, there are two main categories of adult scoliosis: adolescent idiopathic scoliosis of the adult and de novo degenerative scoliosis. Unlike pediatric scoliosis, in adults there are no established radiographic parameters or classification systems that reliably provide a clinical correlation or offer a useful language for communication among specialists. This study gathered complete clinical and radiographic information on 95 patients with adult scoliosis and established several radiographic parameters that correlated with clinical symptoms. METHODS Each of the 95 patients completed a clinical questionnaire that included a self-reported visual analog scale and underwent full-length standing anteroposterior and lateral radiography. Radiographic analysis was performed by use of digital analysis and included measurement of the Cobb angle, the number of vertebrae in each curve, plumbline offset from T1 to the midsacral line, the upper endplate obliquities of L3 and L4, and maximal lateral olisthy between two adjacent lumbar vertebrae. Sagittal plane measurements included lumbar lordosis, thoracolumbar kyphosis, and the Sagittal Pelvic Tilt Index. Statistical analysis of both radiographic and clinical parameters of pain was performed to determine any significant correlations between the two. RESULTS This study showed that lateral vertebral olisthy, L3 and L4 endplate obliquity angles, lumbar lordosis, and thoracolumbar kyphosis were significantly correlated with pain. CONCLUSION This quantitative analysis identified several clinically relevant radiographic parameters in adult scoliosis patients. Additionally, excellent predictive formulas for self-reported pain levels were obtained.

Adult scoliosis: a quantitative radiographic and clinical analysis.

Study design A prospective self-assessment analysis of a consecutive series of adult patients diagnosed with adult scoliosis of adolescent onset or de novo degenerative scoliosis. Purpose To analyze the impact that scoliosis has on patient health perceptions. Summary of background data There exists little data studying the effect scoliosis has on an adult's self-perception of health. Methods Inclusion criteria were: age > or =18 years, Cobb angle greater than 10 degrees, degenerative or idiopathic deformity, no prior surgery (spine), and complete records. Each patient completed the standard Short Form-36 (SF-36) questionnaire. For each patient, radiographic and clinical data were evaluated. After all data were collected, the mean, standard deviation (SD), and true N values of the Cobb angle were calculated. This study population was then divided into two groups: patients with a Cobb angle greater than 10 degrees and patients with a Cobb angle greater than 20 degrees. Comparison of the SF-36 data for adult scoliosis patients with the United States general population, the United States general population ages 55-64, and patients with hypertension and low back pain was undertaken. Results The mean age for the patients in this study was 63 years of age; 22 patients were diagnosed as having adult scoliosis of adolescent onset and 27 patients had de novo degenerative scoliosis. The Cobb angle in this study group was found to be greater than 20 degrees in 41 patients; of these patients, 19 patients had a diagnosis of adult scoliosis of adolescent onset and 22 patients had a diagnosis of de novo degenerative scoliosis. Taken as a whole, the patients in this study averaged scores much lower than the norms for both the general U.S. population in all 8 categories and the U.S. population for ages 55 to 64 in 7 out of 8 categories of the SF-36 questionnaire. Additionally, patients with scoliosis also showed lower scores compared to that of the norms found of patients with comorbid conditions: back pain/sciatica with hypertension in seven of the eight categories: physical functioning, role physical, bodily pain, general health, vitality, social functioning, role emotional, and mental health. Of the radiographic parameters analyzed, loss of lumbar lordosis revealed a significant correlation with social function: P = 0.018; role emotional: P = 0.038; and overall general health: P = 0.05. The other radiographic parameters did not reveal statistically significant correlation to the calculated SF-36 scores. Conclusion Our data clearly demonstrate the impact that adult scoliosis has on a patient's perception of health. The severity of this impact is strikingly apparent in the SF-36 scores when compared to benchmark data on patients with comorbid conditions such as back pain and hypertension. It is our conclusion that adult scoliosis is becoming a medical condition of significant impact, affecting the fastest growing section of our society to a previously unrecognized degree.

Adult scoliosis: a health assessment analysis by SF-36.

STUDY DESIGN This is a prospective radiographic and force plate analysis involving adult volunteer and patients with scoliosis. OBJECTIVE To assess accurately the center of pressure in standing volunteers and patients with scoliosis, and correlate these finding with radiographic data. SUMMARY OF BACKGROUND DATA A simple and commonly applied parameter of global balance is the plumbline offset. This radiographic measurement refers to the center of C2 (or C7) drawn vertically downward. Although this measurement is simple, it may not accurately reflect the balance of the spine. METHODS This study included adult volunteers (n = 41) and patients with scoliosis (n = 45). Full-length, freestanding spine radiographs were obtained with subjects on a force plate. Simultaneous assessment of the radiologic spinal posture and the floor projection of the center of pressure (gravity line) was possible. The latter was projected on the full spine images and correlated to common radiographic parameters. RESULTS The position of the gravity line differed significantly from the plumbline in frontal and sagittal planes (P < 0.001). This difference was maintained in both study populations. The mean frontal plane alignment of the gravity line was consistently to the right of the plumbline. The mean sagittal plane alignment of the gravity in relation to the plumbline revealed an offset anteriorly. CONCLUSIONS The data analysis of offsets between the gravity line and radiographic parameters revealed a frontal plane mean displacement of the gravity line to the right. In the sagittal plane, a highly significant lack of correlation between the gravity line and plumbline was noted. The plumbline represents a common and convenient visual display of apparent sagittal plane imbalance, but its value as a marker of true postural balance must be questioned.

Center of gravity and radiographic posture analysis: a preliminary review of adult volunteers and adult patients affected by scoliosis.

STUDY DESIGN Retrospective consecutive clinical review of 98 patients. OBJECTIVE To create a preliminary approach to a clinically important classification of scoliosis in adult patients. SUMMARY OF BACKGROUND DATA There is currently no accepted classification of scoliosis in adults. High prevalence rates of scoliosis in the elderly and recent studies of health impact support the need for a clinically relevant classification. METHODS A total of 98 adult patients with scoliosis with a 2-year minimum treatment/follow-up were included. Patients were classified into one of 3 types of deformity based on the degree of lordosis (L1-S1) and frontal plane endplate obliquity of L3 on standing radiographs: type I = lordosis > 55 degrees, L3 obliquity 25 degrees. RESULTS Curve patterns included thoracic, thoracolumbar, lumbar, thoracic, and lumbar (mean Cobb angle 30 degrees, standard deviation 19 degrees). Cobb angle revealed no correlation to visual analog pain score (VAS) or general health (36-Item Short-Form Health Survey). Significant correlation between endplate obliquity L3, L1-S1 lordosis and VAS was noted (P < 0.05). Mean pain scores of classified patients were: type I, VAS = 27.7; type II, VAS = 43.3; and type III, VAS = 47.1 (type I vs. III, P < 0.05). Surgical rates (failed minimum 3-month conservative care, including bracing, physical therapy, and pharmacological treatment) by group were: type I, 0%; type II, 9%; and type III, 22.7% (P = 0.002). CONCLUSIONS A simple classification of adult scoliosis was developed based on frontal and sagittal plane standing radiographs. With increasing type (from I to III), self-reported pain and disability increased. This result was reflected in the treatment approach as well, with surgical rates increasing from types I to III. Further refinement is important to develop an all inclusive and sufficiently descriptive system.

Lorenzo Gamez

Papers

Adult scoliosis: prevalence, SF-36, and nutritional parameters in an elderly volunteer population

Adult scoliosis: a quantitative radiographic and clinical analysis.

Adult scoliosis: a health assessment analysis by SF-36.

Center of gravity and radiographic posture analysis: a preliminary review of adult volunteers and adult patients affected by scoliosis.

A lumbar classification of scoliosis in the adult patient : Preliminary approach