Evaluation of the Reliability and Reproducibility of the Roussouly Classification for Lumbar Lordosis Types / Avaliação da confiabilidade e reprodutibilidade da classificação de Roussouly para os tipos de lordose lombar

Abstract Objective The present study aims to determine the intra- and inter-rater reliability and reproducibility of the Roussouly classification for lumbar lordosis types. Methods A database of 104 panoramic, lateral radiographs of the spine of male individuals aged between 18 and 40 years old was used. Six examiners with different expertise levels measured spinopelvic angles and classified lordosis types according to the Roussouly classification using the Surgimap software (Nemaris Inc., New York, NY, USA). After a 1-month interval, the measurements were repeated, and the intra- and inter-rater agreement were calculated using the Fleiss Kappa test. Results The study revealed positive evidence regarding the reproducibility of the Roussouly classification, with reasonable to virtually perfect (0.307-0.827) intra-rater agreement, and moderate (0.43) to reasonable (0.369) inter-rater agreement according to the Fleiss kappa test. The most experienced examiners showed greater inter-rater agreement, ranging from substantial (0.619) to moderate (0.439). Conclusion The Roussouly classification demonstrated good reliability and reproducibility, with intra- and inter-rater agreements at least reasonable, and reaching substantial to virtually perfect levels in some situations. Evaluators with highest expertise levels showed greater intra and inter-rater agreement.

Resumo Objetivo Determinar a confiabilidade e reprodutibilidade intra- e interavaliadores da classificação dos tipos de lordose lombar de Roussouly. Métodos Foram utilizadas 104 radiografias panorâmicas da coluna vertebral em incidência de perfil, de banco de dados, de indivíduos do sexo masculino com idade entre 18 e 40 anos. Utilizando o software Surgimap (Nemaris Inc., Nova York, NY, EUA), seis examinadores com diferentes níveis de experiência aferiram os ângulos espinopélvicos e classificaram o tipo de lordose de acordo com a classificação de Roussouly. Após um intervalo de 1 mês, as mensurações foram realizadas novamente, sendo calculadas as concordâncias intra- e interavaliadores através do teste Kappa de Fleiss. Resultados O estudo demonstrou evidências positivas em relação à reprodutibilidade da classificação de Roussouly, com teste Kappa de Fleiss para concordância intraavaliador entre razoável à quase perfeita (0,307-0,827), e interavaliador entre moderada (0,43) e razoável (0,369). Os examinadores mais experientes apresentaram maior concordância interavaliador, variando entre substancial (0,619) e moderada (0,439). Conclusão A classificação de Roussouly, demonstrou boa confiabilidade e reprodutibilidade, tendo em vista que a concordância intra- e interavaliadores foi considerada no mínimo razoável, podendo atingir os níveis de substanciais à quase perfeitos em algumas situações. Os avaliadores com maior nível de experiência apresentaram maior concordância intra- e interavaliadores.

Improvement in some Ames-ISSG cervical deformity classification modifier grades may correlate with clinical improvement.

This retrospective cohort study describes adult cervical deformity(ACD) patients with Ames-ACD classification at baseline(BL) and 1-year post-operatively and assesses the relationship of improvement in Ames modifiers with clinical outcomes. Patients ≥ 18yrs with BL and post-op(1-year) radiographs were included. Patients were categorized with Ames classification by primary deformity descriptors (C = cervical; CT = cervicothoracic junction; T = thoracic; S = coronal) and alignment/myelopathy modifiers(C2-C7 Sagittal Vertical Axis[cSVA], T1 Slope-Cervical Lordosis[TS-CL], Horizontal Gaze[Horiz], mJOA). Univariate analysis evaluated demographics, clinical intervention, and Ames deformity descriptor. Patients were evaluated for radiographic improvement by Ames classification and reaching Minimal Clinically Important Differences(MCID) for mJOA, Neck Disability Index(NDI), and EuroQuol-5D(EQ5D). A total of 73 patients were categorized: C = 41(56.2%), CT = 18(24.7%), T = 9(12.3%), S = 5(6.8%). By Ames modifier 1-year improvement, 13(17.8%) improved in mJOA, 26(35.6%) in cSVA grade, 19(26.0%) in Horiz, and 15(20.5%) in TS-CL. The overall proportion of patients without severe Ames modifier grades at 1-year was as follows: 100% cSVA, 27.4% TS-CL, 67.1% Horiz, 69.9% mJOA. 1-year post-operatively, severe myelopathy(mJOA = 3) prevalence differed between Ames-ACD descriptors (C = 26.3%, CT = 15.4%, T = 0.0%, S = 0.0%, p = 0.033). Improvement in mJOA modifier correlated with reaching 1-year NDI MCID in the overall cohort (r = 0.354,p = 0.002). For C descriptors, cSVA improvement correlated with reaching 1-year NDI MCID (r = 0.387,p = 0.016). Improvement in more than one radiographic Ames modifier correlated with reaching 1-year mJOA MCID (r = 0.344,p = 0.003) and with reaching more than one MCID for mJOA, NDI, and EQ-5D (r = 0.272,p = 0.020). In conclusion, improvements in radiographic Ames modifier grades correlated with improvement in 1-year postoperative clinical outcomes. Although limited in scope, this analysis suggests the Ames-ACD classification may describe cervical deformity patients' alignment and outcomes at 1-year.

Alignment, Classification, Clinical Evaluation, and Surgical Treatment for Adult Cervical Deformity: A Complete Guide.

Adult cervical deformity management is complex and is a growing field with many recent advancements. The cervical spine functions to maintain the position of the head and plays a pivotal role in influencing subjacent global spinal alignment and pelvic tilt as compensatory changes occur to maintain horizontal gaze. There are various types of cervical deformity and a variety of surgical options available. The major advancements in the management of cervical deformity have only been around for a few years and continue to evolve. Therefore, the goal of this article is to provide a comprehensive review of cervical alignment parameters, deformity classification, clinical evaluation, and surgical treatment of adult cervical deformity. The information presented here may be used as a guide for proper preoperative evaluation and surgical treatment in the adult cervical deformity patient.

Inter-tester Reliability of Lumbar Lordosis Posture Classification Using a Novel Screening Device.

OBJECTIVE: The purpose of this study was to investigate the inter-tester reliability of lumbar lordosis posture using a novel screening device. METHODS: A total of 33 healthy young male participants participated in the study. Two examiners measured the regional upper and lower lumbar lordosis angles of the participants in the standing position using a flexible ruler. The bent flexible ruler maintained a fixed shape and was transferred to a protractor for angle measurement. Two examiners classified each participant into one of 4 lumbar spine categories and measured the upper and lower regional lumbar lordosis angles. RESULTS: The agreement level between the 2 examiners in assessing healthy participants was 87.9%. The calculated kappa coefficient was 0.79 (95% CI = 0.86-0.97), reflecting a substantial level of agreement. CONCLUSION: Our results suggest that our novel screening device for assessing upper and lower lumbar angles showed good inter-tester reliability in posture classification. Our findings may be useful for health care professionals for managing sagittal lumbar posture in asymptomatic younger individuals; however, more testing is still needed.

Degenerative changes of sagittal alignment in patients with Roussouly type 1.

STUDY DESIGN: A cross-sectional radiological study. OBJECTIVES: We aimed to examine the degenerative changes of sagittal alignment in patients with Roussouly type 1. Roussouly type 1 is unique in shape, characterized by short lumbar lordosis (LL) with the apex at L5 and thoracolumbar kyphosis (TLK). Because of the unique shape of sagittal alignment and the small pelvic incidence (PI) in Roussouly type 1, the degenerative changes of sagittal alignment may differ. METHODS: A total of 145 patients with Roussouly type 1 were recruited and distributed into three age groups; Group I (N = 40) were young patients (20-40 years of age), Group II (N = 47) were middle-aged patients (45-60 years of age), and Group III (N = 48) were elderly patients (>65 years of age). Sagittal parameters including sagittal vertical axis (SVA), PI, pelvic tilt (PT), L1S1 LL, L4S1 LL, thoracic kyphosis (TK), and TLK were measured using Surgimap® software. The occurrence of lumbar retrolisthesis was also examined. RESULTS: The SVA, PI, PT, L1S1 LL, L4S1 LL, TK, and TLK in group I were - 25.9° ± 23.4 mm, 37.1° ± 5.3°, 10.3° ± 5.5°, 42.7° ± 8.8°, 35.5° ± 6.9°, 29.5° ± 23.5°, and 9.7° ± 5.9°, respectively. Among the Groups I, II, and III, there was a stepwise increase in the SVA, PT, TLK, and lumbar retrolisthesis (all P < 0.001). The PI, L4S1 LL, and TK were identical among the three groups. CONCLUSIONS: Degenerative changes of Roussouly type 1 include increase in the SVA, PT, TLK, and lumbar retrolisthesis, while the PI, L4S1 LL, and TK remain unchanged. LEVEL OF EVIDENCE: Level IV.

[Comparison of clinical outcomes between type B and type C coronal pattern patients with degenerative scoliosis].

Objective: To investigate the differences of the radiographic and clinical outcomes after posterior correction surgeries between degenerative scoliosis (DS) patients with type B and type C coronal pattern. Methods: From March 2010 to August 2017, the clinical data of 38 patients (type B: 24; type C: 14) who were treated with posterior correction surgeries for DS were retrospectively reviewed. Radiographic parameters including Cobb angle of main curve, coronal imbalance (CI), lumbar lordosis (LL), global kyphosis (GK) and sagittal vertical axis (SVA) were measured on standing anteroposterior and lateral radiographs of the whole spine before and after surgery. Patient-reported outcomes were evaluated by using the visual analogue scale (VAS), the Oswestry disability index (ODI) and SF-36 questionnaire. The independent t-test was applied to compare the difference for statistical analysis. Results: There was no significant differences between the two groups in terms of age, gender, follow-up duration, preoperative curve magnitude, severity of CI, sagittal malalignment and surgical strategies (all P>0.05). In patients with type B coronal pattern, the main curve was corrected from 44°±19° before surgery to 19°±7° immediately after surgery (t=8.496, P<0.001) and to 19°±6° at the last follow-up (t=-0.657, P=0.518). In patients with type C coronal pattern, the main curve was corrected from 43°±9° before surgery to 21°±4° immediately after surgery (t=13.537, P<0.001) and to 21°±5° at the last follow-up (t=-0.186, P=0.856). No significant difference of Cobb angle of main curve was found between the two groups either before the operation or immediately post operation (all P>0.05). In addition, significant improvement of CI was observed after surgery in both groups and the correction was maintained well at the last follow-up. However, patients with type C coronal pattern had greater CI than that in those with type B coronal pattern immediately post operation (t=-2.401, P=0.022) and at the last follow-up (t=-2.659, P=0.012). At the last follow-up the scores of SF-36 questionnaire, ODI and VAS showed significant improvement in both groups (all P<0.05). Conclusion: Posterior correction surgery could provide remarkable radiographic and clinical outcomes in DS patients with type B and type C coronal pattern, and DS patients with type B coronal pattern could achieve a more satisfied coronal balance after surgery.

Prediction of mechanical complications in adult spinal deformity surgery-the GAP score versus the Schwab classification.

BACKGROUND CONTEXT: Surgery for adult spinal deformity is a challenging and complex procedure with high reported complication (8.4%-42%) and revision rates (9%-17.6%). Failure to achieve or maintain adequate postoperative sagittal alignment has been reported to be the main cause of mechanical complications. In order to define appropriate surgical targets, the Scoliosis Research Society-Schwab classification and the Global Alignment and Proportion (GAP) score were established. In the literature, no study has yet compared these classification systems with respect to the risk of developing mechanical complications. PURPOSE: To assess and compare the ability of the Schwab classification and the GAP score to predict mechanical complications following adult spinal deformity surgery. STUDY DESIGN: Two-center, retrospective cohort study. PATIENT SAMPLE: Thirty-nine patients suffering adult spinal deformity who underwent long segment spinal fusion (≥4 levels), minimum follow-up of 2years. OUTCOME MEASURES: The ability of the Schwab classification and GAP score to predict mechanical failure was determined by computing the Area Under the receiver operating characteristic curve. METHODS: Full-spine pre- and postoperative radiographs of all patients were analyzed for mechanical complications. Subsequently, the pre- and postoperative Schwab and GAP score were determined. Logistic regression analysis was used to assess the ability of both systems to determine which was the most appropriate for the prediction of mechanical failure. Correlations between the various factors constituting the GAP score and Schwab classification were estimated using the Spearman rank order correlation coefficient. RESULTS: The results demonstrated that both classification systems are capable of predicting radiographic evidence of mechanical failure; however, the GAP score proved to be significantly better (p=.003). The relative pelvic version of the GAP score serves a similar role as the pelvic tilt modifier from the Schwab classification (ρ=-0.84, p<.01). The relative lumbar lordosis from the GAP score functions much like the PI-LL modifier from the Schwab classification (ρ=-0.94, p<.01). The GAP score is most significantly dependent on relative spinopelvic alignment, relative lumbar lordosis, and relative pelvic version (ρ=0.85, ρ=0.84, and ρ=0.84, respectively, p<.01). Correlation with the lordosis distribution index was also significant but was not as strong (ρ=0.65, p<.01). Age, on the contrary, showed poor correlation with the GAP score (ρ=0.17, p=.300). CONCLUSIONS: Both the Schwab classification and the GAP score are capable of predicting mechanical complications. The GAP score proved to be significantly more appropriate. This difference is probably attributed to the fact that in the GAP score all parameters are related to the patient's individual pelvic incidence.

The sagittal spinal profile type: a principal precondition for surgical decision making in patients with lumbar spinal stenosis.

OBJECTIVE Microsurgical decompression (MD) in patients with lumbar spinal stenosis (LSS) shows good clinical results. Nevertheless, 30%-40% of patients do not have a significant benefit after surgery-probably due to different anatomical preconditions. The sagittal profile types (SPTs 1-4) defined by Roussouly based on different spinopelvic parameters have been shown to influence spinal degeneration and surgical results. The aim of this study was to investigate the influence of the SPT on the clinical outcome in patients with LSS who were treated with MD. METHODS The authors retrospectively investigated 100 patients with LSS who received MD. The patients were subdivided into 4 groups depending on their SPT, which was determined from preoperative lateral spinal radiographs. The authors analyzed pre- and postoperative outcome scales, including the visual analog scale (VAS), walking distance, Oswestry Disability Index, Roland-Morris Disability Questionnaire, Odom's criteria, and the 36-Item Short Form Health Survey score. RESULTS Patients with SPT 1 showed a significantly worse clinical outcome concerning their postoperative back pain (VASback-SPT 1 = 5.4 ± 2.8; VASback-SPT 2 = 2.6 ± 1.9; VASback-SPT 3 = 2.9 ± 2.6; VASback-SPT 4 = 1.5 ± 2.5) and back pain-related disability. Only 43% were satisfied with their surgical results, compared with 70%-80% in the other groups. CONCLUSIONS A small pelvic incidence with reduced compensation mechanisms, a distinct lordosis in the lower lumbar spine with a high load on dorsal structures, and a long thoracolumbar kyphosis with a high axial load might lead to worse back pain after MD. Therefore, the indication for MD should be provided carefully, fusion can be considered, and other possible reasons for back pain should be thoroughly evaluated and treated.

Does the type of sagittal spinal shape influence the clinical results of lumbar disc arthroplasty?

INTRODUCTION: It has been suggested that the indication for lumbar total disc replacement (LTDR) takes into account the local parameters, such as the type of disc disease demonstrated on MRI and the presence or absence of facet joint osteoarthritis. The type of preoperative sagittal curvature could also be taken into account. This study reports the clinical results of LTDRs depending on the type of sagittal spinal alignment. MATERIAL AND METHODS: Eighty patients were included in this prospective study, with a mean age of 41.7years (range, 27-56years). The clinical analysis took into account the lumbar VAS, the Oswestry Disability Index (ODI), and the preoperative frequency of painkiller use, at 1year and at the last follow-up. The satisfaction index, return to work, and willingness to undergo the same treatment were also collected. The radiological study included the analysis of lumbar-pelvic parameters to distribute the patients according to the Roussouly classification. RESULTS: The mean follow-up was 59.1months (range, 14-96months). The type 1 group included four cases. Reduction of the VAS, the ODI score, and the frequency of painkiller use at the last follow-up were significant in type 2 and 3 patients, and non-significant for type 4. Eighty-five percent of type 2 patients and 87.5% of type 3 patients were satisfied or very satisfied with the surgery versus only 68% of the type 4 patients. In addition, 63% of the type 4 patients declared they would be willing to undergo the same treatment again versus 85% of the type 2 patients and 82.5% of the type 3 patients. It should also be noted that 67% of the patients in this series returned to work. DISCUSSION AND CONCLUSION: This study underscores the influence of the type of sagittal curvature on the clinical results of LTDR, with type 4 patients showing inferior clinical results because of a higher rate of residual lower back pain. The indication in LTDR should be reconsidered for discogenic lower back pain in type 4 patients.

Cervical curvature variations in patients with infraocclusion.

The purpose of this study was to observe the variations of cervical curvature in patients with infraocclusion, and to compare this with the controls. In this study, the infraocclusion criteria were defined with the Pr-id as <17 mm on the cephalometric image. The subjects were 32 patients with infraocclusion, and 28 controls which matched the distribution for gender and age. The six points of inquiry were as follows: (i) cervical vertebra height, (ii) neck alignment, (iii) ratio of lower facial height, (iv) vertical dimension of occlusion, (v) cervical angle and (vi) occlusal angle. In over 90% of the patients with infraocclusion, the cervical curvature was classified as straight or kyphosis. Conversely, in 36% of the control subjects, the cervical curvature was classified as lordosis. There was a weak positive correlation between the vertical dimension of occlusion and the cervical curvature in all subjects. In the control group, there was a significant and strong positive correlation between the age and cervical curvature, and a strong negative correlation between age and cervical angle and occlusal angle. Conversely, in the patients with infraocclusion, age was only correlated with the ratio of lower facial height. The prevalence of non-lordosis in the patients with infraocclusion was higher in comparison with the control group in our study, and the previous large-scale study of Japanese. However, there was merely a weak positive correlation between the cervical curvature and the vertical dimension of occlusion.

Analysis of the cervical spine sagittal alignment in young idiopathic scoliosis: a morphological classification of 120 cases.

PURPOSE: To analyze the relationship between the cervical spine and global spinal-pelvic alignment in young patients with idiopathic scoliosis based on a morphological classification, and to postulate the hypothesis that cervical kyphosis is a part of cervico-thoracic kyphosis in them. METHODS: 120 young patients with idiopathic scoliosis were recruited retrospectively between 2006 and 2011. The following values were measured and calculated: cervical angles (CA), cervico-thoracic angles (CTA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), spinal sacral angle (SSA), hip to C7/hip to sacrum, thoracic kyphosis (TK), lumbar lordosis (LL), Roussouly sagittal classification, Lenke Type Curve and Lumbar Modifier. The cervical curves were classified as lordosis, straight, sigmoid and kyphosis. They were categorized into four groups as cervical non-kyphosis group (CNK Group), cervical kyphosis group (CK Group), cervical-middle-thoracic kyphosis group (CMTK Group), and cervical-lower-thoracic kyphosis group (CLTK Group) according to their morphological characters of sagittal alignments. All parameters were compared and analyzed among groups. RESULTS: The incidence of cervical kyphosis was 40 % (48/120). The CA and the CTA were in significant correlation (r = 0.854, P = 0.00). The cervical spine alignments were revealed to be significantly different among groups (r = 85.04, P = 0.00). Significant differences among groups in CA, CTA and TK were also detected. A strong correlation between the group type and Lenke Lumbar Modifier was still seen (P < 0.05). Fisher's exact test revealed that the individual vertebral body kyphosis and wedging were directly related to the overall cervical kyphosis (P = 0.00, respectively). CONCLUSION: The cervical kyphosis is correlated with global sagittal alignment, and is a part of cervico-thoracic sagittal deformity in young patients with idiopathic scoliosis. Despite the deformity in cervical alignment, the global spine could still be well-balanced with spontaneous adjustment. The correlation between our grouping based on the morphological characteristics of the sagittal alignments and Lenke Lumbar Modifier suggests that the coupled motion principle be appropriate to explain the modifications both in coronal and sagittal planes.

Lumbar degenerative kyphosis: radiologic analysis and classifications.

STUDY DESIGN: Retrospective study of a consecutive patient series. OBJECTIVES: To review the radiographic classification of patients with sagittal imbalance due to lumbar degenerative kyphosis (LDK) and to determine correlation between thoracic and lumbar curve. SUMMARY OF BACKGROUND DATA: Lumbar degenerative kyphosis is one of the common spinal deformities in Asian countries, especially Korea and Japan. However, there have been few studies regarding the classification and treatment of this disease. METHODS: Seventy-eight patients with LDK were analyzed and classified according to the standing lateral whole spine findings. Total lumbar lordosis (L1-S1), thoracic kyphosis (T5-T12), sacral slope, thoracolumbar angle (T11-L1), and sagittal vertical axis (SVA) were measured on the lateral view of the whole spine. Spinal curve deformities were classified into 2 groups according to the thoracolumbar (T-L) junction angle: flat or lordotic angle (Group 1; N = 53) and kyphotic angle (Group 2; N = 25). RESULTS: In Group 1, significant correlations between the thoracic and lumbar curves (r = 0.772, P < 0.0001), and between the lumbar curve and sacral slope (r = 0.785, P < 0.0001) were observed. By this result, Group 1 was classified as sagittal thoracic compensated group. In contrast, In Group 2, no correlation was found between the thoracic and lumbar curves in the decompensated group (r = 0.179, P = 0.391), but we found a significant correlation between lordosis and sacral slope (r = 0.442, P = 0.027). By this result, Group 2 was classified as sagittal thoracic decompensated group. There was significant difference in SVA between 2 groups (P = 0.020). CONCLUSION: The angle of the thoracolumbar junction is an important parameter in determining whether a sagittal thoracic compensatory mechanism exists in LDK. We assumed that existence of a compensatory mechanism in the proximal spine is central to the determination of the fusion levels in the treatment of LDK.

Surgical rates and operative outcome analysis in thoracolumbar and lumbar major adult scoliosis: application of the new adult deformity classification.

STUDY DESIGN: Multicenter prospective consecutive clinical series. OBJECTIVE: Investigate the interaction between the Adult Deformity Classification and treatment patterns, surgical strategies, surgery effectiveness, and complication rates. SUMMARY OF BACKGROUND DATA: An Adult Deformity Classification has been established that applies radiographic parameters of disability. Preliminary intraobserver and interobserver analysis reveals excellent reliability of the classification. Outcomes studies have not been reported to date. METHODS: A total of 784 adult patients with thoracolumbar or lumbar deformity underwent radiographic evaluation (full-length frontal/sagittal) as well as health assessment: Oswestry Disability Index, Scoliosis Research Society-22, and SF-12. Patients were subdivided by treatment and surgical strategies; 1 year (111 patients) and 2 year (45 patients) follow-up data were analyzed. Interaction between classification, treatment, surgical strategy, health assessment changes, and complications were analyzed. RESULTS: Classification modifiers (lordosis, subluxation, sagittal balance) were found to have significant variation (higher rates) in surgical care as the grade of the modifier increased. Classification differentiated patients by surgical approach and/or technique. Interaction between classification and baseline health assessment impacts both postoperative health scores and complication rates. CONCLUSION: This investigation appears to offer the first comprehensive analysis of classification, treatment, and outcomes in a large adult deformity patient group. Significant treatment patterns and outcomes are coming to light as is the impact of surgical strategy.

A clinical impact classification of scoliosis in the adult.

STUDY DESIGN: Multicenter, prospective, consecutive clinical series. OBJECTIVES: To establish and validate classification of scoliosis in the adult. SUMMARY OF BACKGROUND DATA: Studies of adult scoliosis reveal the impact of radiographic parameters on self-assessed function: lumbar lordosis and frontal plane obliquity of lumbar vertebrae, not Cobb angle, correlate with pain scores. Deformity apex and intervertebral subluxations correlate with disability. METHODS: A total of 947 adults with spinal deformity had radiographic analysis: frontal Cobb angle, deformity apex, lumbar lordosis, and intervertebral subluxation. Health assessment included Oswestry Disability Index and Scoliosis Research Society instrument. Deformity apex, lordosis (T12-S1), and intervertebral subluxation were used to classify patients. Outcomes measures and surgical rates were evaluated. RESULTS: Mean maximal coronal Cobb was 46 degrees and lumbar lordosis 46 degrees . Mean maximal intervertebral subluxation (frontal plane) was 4.2 mm (sagittal plane, 1.2 mm). In thoracolumbar/lumbar deformities, the loss of lordosis/higher subluxation was associated with lower Scoliosis Research Society pain/function and higher Oswestry Disability Index scores. Across the study group, lower apex combined with lower lordosis led to higher disability. Higher surgical rates with decreasing lumbar lordosis and higher intervertebral subluxation were detected. CONCLUSIONS: A clinical impact classification has been established based on radiographic markers of disability. The classification has shown correlation with self-reported disability as well as rates of operative treatment.

A lumbar classification of scoliosis in the adult patient: preliminary approach.

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 < 15 degrees; type II = lordosis 35 degrees-55 degrees, L3 obliquity 15 degrees-25 degrees; and type III = lordosis < 35 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.

Classification of the normal variation in the sagittal alignment of the human lumbar spine and pelvis in the standing position.

STUDY DESIGN: A prospective radiographic study of 160 volunteers without symptoms of spinal disease was conducted. OBJECTIVES: The objective of this study was to describe, quantify, and classify common variations in the sagittal alignment of the spine, sacrum, and pelvis. SUMMARY OF BACKGROUND DATA: Previous publications have documented the high degree of variability in the sagittal alignment of the spine. Other studies have suggested that specific changes in alignment and the characteristics of the lumbar lordosis are responsible for degenerative changes and symptomatic back pain. METHODS: In the course of this study, anteroposterior and lateral radiographs of 160 volunteers in a standardized standing position were taken. A custom computer application was used to analyze the alignment of the spine and pelvis on the lateral radiographs. A four-part classification scheme of sagittal morphology was used to classify each patient. RESULTS: Reciprocal relationships between the orientation of the sacrum, the sacral slope, the pelvic incidence, and the characteristics of the lumbar lordosis were evident. The global lordotic curvature, lordosis tilt angle, position of the apex, and number or lordotic vertebrae were determined by the angle of the superior endplate of S1 with respect to the horizontal axis. CONCLUSIONS: Understanding the patterns of variation in sagittal alignment may help to discover the association between spinal balance and the development of degenerative changes in the spine.

Reliability and validity of classification of senile postural deformity in mass examinations.

Nakada (1988) divided senile postural deformities into four types by visual observation: an extended type, an S-shaped type, a flexed type, and a hand-on-the-lap type. The purpose of this study was to investigate the inter-rater reliability and the discriminant validity of assessing the elderly spinal posture using a posture-measuring device developed by us and dividing postural deformities into the four types of Nakada's classification. Seventy-seven elderly persons (52 women and 25 men) who lived independently participated in the study. The average age of the subjects was 73 years (range, 65 to 84 years). The type of the senile postural deformity was determined by three judges using our posture-measuring device in combination with Nakada's classification. The rate of agreement of the classification was 92.2%. This method had a significantly high rate of inter-rater reliability. The thoracic kyphotic angle was larger in the S-shaped type than in the normal, extended type, and flexed type. The lumbar lordotic angle was also larger in the S-shaped type than in the extended type, flexed type, and hand-on-the-lap type. In the hand-on-the-lap type, the mean of the lumbar lordotic angle was much smaller. The lumbosacral angle was smaller in the extended type than in the normal, S-shaped type, and flexed type. With the analysis of x-ray photographs, this method appeared to have discriminant validity as a measure of senile postural deformity. The combination of our posture-measuring device and Nakada's classification would be useful to classify senile postural deformities in mass examinations.

[Geometrical and mechanical analysis of lumbar lordosis in an asymptomatic population: proposed classification]. / Analyse géométrique et mécanique de la lordose lombaire dans une population de 160 adultes asymptomatiques: essai de classification.

PURPOSE OF THE STUDY: The main objective of this study was to describe the morphology and the mechanism underlying the organization of lumbar lordosis in terms of position and shape of the pelvis. A classification of lumbar lordosis was proposed based on the orientation of the sacral plane. MATERIAL AND METHODS: One hundred sixty asymptomatic young adult volunteers were x-rayed in a standardized standing position. A dedicated software was used for analysis of the spine and pelvis. The pelvic parameters were: pelvic incidence, sacral slope, pelvic tilt. The point separating thoracic kyphosis and lumbar lordosis was called the inflexion point. Lumbar lordosis was bounded by the sacral plate and the inflexion point. At the apex, the lumbar curve was divided into two tangent arcs of circle, quantified by an angle and the number of included vertebrae. The lower arc was geometrically equal to the sacral slope. Regarding the vertical line, a lordosis tilt angle was drawn between the inflexion point and the frontal limit of the sacral plate. RESULTS: The value of the lumbar lordosis was very variable. The best correlation was between lumbar lordosis and sacral slope, then between sacral slope and pelvic incidence. The upper arc of a circle remained constant while the lower arc changed with sacral slope. Good correlations were found between the sacral slope and the position of the apex and between sacral slope and lordosis tilt angle. DISCUSSION AND CONCLUSION: Regarding sacral slope, lumbar lordosis can be classified into four types. When the sacral slope is low, lumbar lordosis can either be both short and curved with a low apex and a backward tilt (type 1) or both long and flat with a higher position of the apex (type 2). When the sacral slope increases, lumbar lordosis increases in angle and number of vertebrae with an upper apex, with a progressively forward tilt (types 3 and 4). Depending on the shape and position of the pelvis, and because of the relation between sacral slope and pelvic tilt, the morphology of lumbar lordosis could be the main mechanical cause of degenerative diseases of the lumbar spine.